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Berkeley Sensor & Actuator Center
 

The Berkeley Sensor & Actuator Center (BSAC) is the Graduated National Science Foundation Industry/University Cooperative Research Center for Microsensors and Microactuators. We conduct industry-relevant, interdisciplinary research on micro- and nano-scale sensors, moving mechanical elements, microfluidics, materials, processes & systems that take advantage of progress made in integrated-circuit, bio, and polymer technologies.

BSAC Current Active Projects as of March 28, 2015

Number of records: 97
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PROJECT MATERIALS
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PROJECT TITLEADVISOR
1Physical Sensors & DevicesBPN783BPN783 WebsiteLow Power Conductometric Soot Sensor With Fast Self-Regeneration New ProjectRoya Maboudian
2NanoPlasmonics, Microphotonics & ImagingBPN786BPN786 WebsiteNanoPlasmonics for Sensing and Energy New ProjectRoya Maboudian, Carlo Carraro
3NanoTechnology: Materials, Processes & DevicesBPN790BPN790 WebsiteLow power microheater based sensing platform for breath analysis New ProjectRoya Maboudian, Carlo Carraro, Willi Mickelson
4NanoTechnology: Materials, Processes & DevicesBPN762BPN762 WebsiteMicroheater-Based Platform for Low Power Combustible Gas SensingRoya Maboudian, Willi Mickelson, Alex Zettl
5Physical Sensors & DevicesBPN424BPN424 WebsiteSilicon Carbide Nanomaterials for Harsh Environment ApplicationsRoya Maboudian, Carlo Carraro
6Wireless, RF & Smart DustBPN767BPN767 WebsiteMEMS-Based Tunable Channel-Selecting Super-Regenerative RF TransceiversClark T.-C. Nguyen
7Wireless, RF & Smart DustBPN359BPN359 WebsiteMicromechanical Disk Resonator-Based OscillatorsClark T.-C. Nguyen, Elad Alon
8Wireless, RF & Smart DustBPN540BPN540 WebsiteTemperature-Stable Micromechanical Resonators and FiltersClark T.-C. Nguyen
9Package, Process & MicroassemblyBPN734BPN734 WebsitePackage-Derived Influences on Micromechanical Resonator StabilityClark T.-C. Nguyen
10Physical Sensors & DevicesBPN534BPN534 WebsiteFully-Integrated Micromechanical Clock OscillatorClark T.-C. Nguyen
11Wireless, RF & Smart DustBPN707BPN707 WebsiteAutomated Passband Tuning of High-Order Microelectromechanical FiltersClark T.-C. Nguyen
12Physical Sensors & DevicesBPN433BPN433 WebsiteA Micromechanical Power ConverterClark T.-C. Nguyen
13Physical Sensors & DevicesBPN435BPN435 WebsiteA Micromechanical Power AmplifierClark T.-C. Nguyen
14Wireless, RF & Smart DustBPN682BPN682 WebsiteStrong I/O Coupled High-Q Micromechanical FiltersClark T.-C. Nguyen
15Wireless, RF & Smart DustBPN676BPN676 WebsiteQ-Boosted Optomechanical OscillatorsClark T.-C. Nguyen, Ming C. Wu
16Wireless, RF & Smart DustBPN701BPN701 WebsiteBridged Micromechanical FiltersClark T.-C. Nguyen
17Wireless, RF & Smart DustBPN709BPN709 WebsiteTunable & Switchable Micromechanical RF FiltersClark T.-C. Nguyen
18Wireless, RF & Smart DustBPN683BPN683 WebsiteOpenWSN: A Standards-Based Low-Power Wireless Development EnvironmentKristofer S.J. Pister
19Wireless, RF & Smart DustBPN789BPN789 WebsiteReconfigurable, Wearable Sensors to Enable Long-Duration Circadian Biomedical Studies New ProjectKristofer S.J. Pister
21Wireless, RF & Smart DustBPN744BPN744 WebsiteSelf-Destructing SiliconKristofer S.J. Pister, Michel M. Maharbiz
22Wireless, RF & Smart DustBPN735BPN735 WebsiteAutonomous Microrobotic SystemsKristofer S. J. Pister
23Physical Sensors & DevicesBPN768BPN768 WebsitePlug-Through Energy Monitor for Wall Outlet Electrical DevicesKristofer S.J. Pister
24Physical Sensors & DevicesBPN705BPN705 WebsiteStandard CMOS-Based, Fully Integrated, Stick-On Electricity Meters for Building Sub-MeteringKristofer S.J. Pister, Steven Lanzisera
25Physical Sensors & DevicesBPN608BPN608 WebsiteFM GyroscopeBernhard E. Boser
26BioMEMSBPN649BPN649 WebsiteMagnetic Particle Flow CytometerBernhard E. Boser
27BioMEMSBPN685BPN685 WebsiteReal-Time Intraoperative Fluorescent Imager for Microscopic Residual Tumor in Breast CancerBernhard E. Boser, Mekhail Anwar
28Physical Sensors & DevicesBPN722BPN722 WebsitePulse-Echo Ultrasonic Fingerprint Sensor on a ChipBernhard E. Boser
29NanoPlasmonics, Microphotonics & ImagingBPN665BPN665 WebsiteFrequency Modulated Laser Source for 3D ImagingBernhard E. Boser, Ming C. Wu, Eli Yablonovitch, Connie J. Chang-Hasnain
30Physical Sensors & DevicesBPN764BPN764 WebsiteUntethered Stress-Engineered MEMS MicroFlyersIgor Paprotny
31Wireless, RF & Smart DustBPN392BPN392 WebsiteMobile Airborne Particulate Matter Monitor for Cellular DeploymentRichard M. White, Lara Gundel, Igor Paprotny
32Physical Sensors & DevicesBPN738BPN738 WebsiteSensor Instrumentation to Improve Safety of U.S. Underground Coal MinesRichard M. White, Igor Paprotny, Paul K. Wright, Lara Gundel
33Physical Sensors & DevicesBPN697BPN697 WebsiteNatural Gas Pipeline ResearchRichard M. White, Paul K. Wright, Igor Paprotny
34Wireless, RF & Smart DustRMW29RMW29 WebsiteElectric Power Sensing for Demand ResponseRichard M. White, Paul K. Wright
35MicrofluidicsBPN787BPN787 Website3D-Printed Molds for Rapid Assembly of PDMS-based Microfluidic Devices New ProjectLiwei Lin
36MicrofluidicsBPN774BPN774 Website3D Printed Integrated Microfluidic CircuitryLiwei Lin, Luke P. Lee, Ryan D. Sochol
37MicrofluidicsBPN775BPN775 WebsiteIntegrated Microfluidic Circuitry via Optofluidic LithographyLiwei Lin, Luke P. Lee, Ryan D. Sochol
38MicrofluidicsBPN706BPN706 WebsiteSingle-Layer Microfluidic Gain Valves via Optofluidic LithographyLiwei Lin
39MicropowerBPN782BPN782 WebsiteDirect-write nanofibers for flexible energy storage New ProjectLiwei Lin
40Physical Sensors & DevicesBPN784BPN784 WebsiteAluminum Gallium Nitride 2DEG Sensors and Devices New ProjectLiwei Lin
41NanoTechnology: Materials, Processes & DevicesBPN736BPN736 WebsiteAtomic Layer Deposition Ruthenium Oxide SupercapacitorsLiwei Lin
42NanoTechnology: Materials, Processes & DevicesBPN672BPN672 WebsiteSolar Hydrogen Production by Photocatalytic Water SplittingLiwei Lin
43MicropowerBPN737BPN737 WebsiteGraphene-Based Microliter-Scale Microbial Fuel CellsLiwei Lin
44MicropowerBPN742BPN742 Website3D Carbon-Based Materials for Electrochemical ApplicationsLiwei Lin
45Physical Sensors & DevicesBPN743BPN743 WebsiteHighly Responsive pMUTsLiwei Lin
46Wireless, RF & Smart DustBPN574BPN574 WebsiteOn-Chip Micro-InductorLiwei Lin
47Physical Sensors & DevicesBPN772BPN772 WebsiteGraphene for Flexible and Tunable Room Temperature Gas SensorsLiwei Lin
48MicrofluidicsBPN778BPN778 WebsiteSingle-cell MicroRNA Quantification for Gene Regulation Heterogeneity Study New ProjectLuke P. Lee
49MicrofluidicsBPN794BPN794 WebsiteBubble-free Microfluidic PCR New ProjectLuke P. Lee
50NanoTechnology: Materials, Processes & DevicesBPN727BPN727 WebsiteOn-Chip Single Molecule miRNA Detection for Cancer DiagnosisLuke P. Lee
51MicrofluidicsBPN773BPN773 WebsiteHuman Induced Pluripotent Stem Cell-derived Hepatocytes (hiPSC-HPs)-based Organs on ChipLuke P. Lee
52MicrofluidicsBPN730BPN730 WebsiteMicrofluidic Blood Plasma Separation for Point-of-Care DiagnosticsLuke P. Lee
53NanoPlasmonics, Microphotonics & ImagingBPN791BPN791 WebsiteIntegrated Photobioreactor with Optical Excitation Membranes (iPOEMs) for Efficient Photosynthetic Light Harvesting New ProjectLuke P. Lee
54MicrofluidicsBPN679BPN679 WebsitePortable Microfluidic Pumping System for Point-Of-Care DiagnosticsLuke P. Lee
55NanoPlasmonics, Microphotonics & ImagingBPN703BPN703 WebsiteDirectly Modulated High-Speed nanoLED Utilizing Optical Antenna Enhanced Light EmissionMing C. Wu
56NanoPlasmonics, Microphotonics & ImagingBPN721BPN721 WebsiteMEMS-Electronic-Photonic Heterogeneous Integration (MEPHI) Component Fabrication, Design, and CharacterizationMing C. Wu
57NanoPlasmonics, Microphotonics & ImagingBPN788BPN788 WebsiteOptical Phased Array for LIDAR New ProjectMing C. Wu
58NanoPlasmonics, Microphotonics & ImagingBPN751BPN751 Website50x50 Silicon Photonic MEMS Switch with Microsecond Response TimeMing C. Wu
59NanoPlasmonics, Microphotonics & ImagingBPN609BPN609 WebsiteUltra-Sensitive Photodetectors on Silicon PhotonicsMing C. Wu
60NanoPlasmonics, Microphotonics & ImagingBPN458BPN458 WebsiteOptical Antenna-Based nanoLEDMing C. Wu, Ali Javey
61MicrofluidicsBPN552BPN552 WebsiteLight-Actuated Digital Microfluidics (Optoelectrowetting)Ming C. Wu
62MicrofluidicsBPN733BPN733 WebsiteOptoelectronic Tweezers for Long-Term Single Cell CultureMing C. Wu, Song Li
63Package, Process & MicroassemblyBPN354BPN354 WebsiteThe Nanoshift Concept: Innovation through Design, Development, Prototyping and Fabrication of MEMS, Microfluidics, Nano and Clean TechnologiesJohn M. Huggins
64Package, Process & MicroassemblyBPN712BPN712 WebsiteBridging Research-to-Commercialization Gaps In an Industry/ University EcosystemJohn M. Huggins, Ali Javey, Kristofer S.J. Pister
65Physical Sensors & DevicesBPN655BPN655 WebsiteMaterials for High Quality-Factor Resonating GyroscopesDavid A. Horsley
66Physical Sensors & DevicesBPN781BPN781 Website3-Axis MEMS Gyroscope New ProjectDavid A. Horsley
67Physical Sensors & DevicesBPN603BPN603 WebsiteMicro Rate-Integrating Gyroscope New ProjectDavid A. Horsley
68Physical Sensors & DevicesBPN684BPN684 WebsiteIntegrated Microgyroscopes with Improved Scale-Factor and Bias StabilityDavid A. Horsley
69Physical Sensors & DevicesBPN599BPN599 WebsiteMEMS Electronic Compass: Three-Axis MagnetometerDavid A. Horsley
70Physical Sensors & DevicesBPN785BPN785 WebsiteScandium-doped AlN for MEMS New ProjectDavid A. Horsley
71Physical Sensors & DevicesBPN466BPN466 WebsiteAir-Coupled Piezoelectric Micromachined Ultrasound TransducersDavid A. Horsley
72Physical Sensors & DevicesBPN628BPN628 WebsiteNovel Ultrasonic Fingerprint Sensor Based on High-Frequency Piezoelectric Micromachined Ultrasonic Transducers (PMUTs)David A. Horsley
73Physical Sensors & DevicesBPN780BPN780 WebsiteImpedance Spectroscopy to Monitor Fracture Healing New ProjectMichel M. Maharbiz
74Physical Sensors & DevicesBPN714BPN714 WebsiteImpedance Sensing Device to Monitor Pressure UlcersMichel M. Maharbiz
75Physical Sensors & DevicesBPN765BPN765 WebsiteFull-Field Strain Sensor for Hernia Mesh RepairsMichel M. Maharbiz
76BioMEMSBPN769BPN769 WebsiteAcousto-Optic Modulation of Brain Activity: Novel Techniques for Optogenetic Stimulation and ImagingMichel M. Maharbiz
77BioMEMSBPN699BPN699 WebsiteA Modular System for High-Density, Multi-Scale ElectrophysiologyMichel M. Maharbiz, Timothy J. Blanche
78BioMEMSBPN745BPN745 WebsiteWafer-Scale Intracellular Carbon Nanotube-Based Neural ProbesMichel M. Maharbiz
79BioMEMSBPN716BPN716 WebsiteNeural Dust: An Ultrasonic, Low Power Solution for Chronic BrainMachine InterfacesMichel M. Maharbiz
80BioMEMSBPN718BPN718 WebsiteDirect Electron-Mediated Control of Hybrid Multi-Cellular RobotsMichel M. Maharbiz
81BioMEMSBPN795BPN795 WebsiteAn Implantable Micro-Sensor for Cancer Surveillance New ProjectMichel M. Maharbiz, Kristofer S.J. Pister
82Physical Sensors & DevicesBPN731BPN731 WebsiteFlexible Electrodes and Insertion Machine for Stable, Minimally-Invasive Neural RecordingMichel M. Maharbiz, Philip N. Sabes
83BioMEMSBPN573BPN573 WebsiteCarbon Fiber Microelectrode Arrays for Chronic Stimulation and Recording in InsectsMichel M. Maharbiz, Kristofer S.J. Pister
84BioMEMSBPN571BPN571 WebsiteImplantable Microengineered Neural Interfaces for Studying and Controlling InsectsMichel M. Maharbiz
86BioMEMSBPN771BPN771 WebsiteSilicon Carbide ECoGs for Chronic Implants in Brain-Machine InterfacesMichel M. Maharbiz, Roya Maboudian
87BioMEMSBPN756BPN756 WebsiteMEMS Devices for Oral Delivery of Proteins and PeptidesDorian Liepmann, Niren Murthy
88BioMEMSBPN757BPN757 WebsiteBiosensors Based on Biologically Responsive PolymersDorian Liepmann, Niren Murthy
89BioMEMSBPN729BPN729 WebsiteDevelopment of Microfluidic Devices with Embedded Microelectrodes using Electrodeposition and Hot EmbossingDorian Liepmann
90MicrofluidicsBPN711BPN711 WebsitePoint-of-Care System for Quantitative Measurements of Blood Analytes Using Graphene-Based SensorsDorian Liepmann
91MicrofluidicsBPN732BPN732 WebsiteThe Role of Erythrocyte Size and Shape in Microchannel Fluid DynamicsDorian Liepmann
92Physical Sensors & DevicesBPN770BPN770 WebsiteChemical Sensitive Field Effect Transistor (CS-FET)Ali Javey
93NanoTechnology: Materials, Processes & DevicesBPN704BPN704 WebsiteVapor-Liquid-Solid Growth of Polycrystalline Indium Phosphide Thin Films on MetalAli Javey
94NanoTechnology: Materials, Processes & DevicesBPN792BPN792 WebsiteThin Film InP Photoelectrochemical Cells for Efficient, Low-Cost Solar Fuel Production New ProjectAli Javey
95NanoTechnology: Materials, Processes & DevicesBPN777BPN777 WebsiteNonepitaxial Growth of Single Crystalline III-V Semiconductors onto Insulating Substrates New ProjectAli Javey
96Physical Sensors & DevicesBPN747BPN747 WebsiteElectronic Skin: Fully Printed Electronic Sensor NetworksAli Javey
97NanoTechnology: Materials, Processes & DevicesBPN776BPN776 WebsiteWearable Electronic TapeAli Javey
98Physical Sensors & DevicesBPN746BPN746 WebsiteLiquid Heterojunction SensorsAli Javey
99NanoTechnology: Materials, Processes & DevicesBPN694BPN694 WebsiteMonolayer Semiconductor DevicesAli Javey

Project Abstracts

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Table of Projects
Physical Sensors & Devices
Project IDBPN783 New Project
Project Title Low Power Conductometric Soot Sensor With Fast Self-Regeneration
Status New
Funding Source NSF
Keywords
Researchers Ameya Rao
Abstract We are working on designing a conductometric soot sensor that measures the change in conductance resulting from soot deposition onto the sensor. Although some work has been done on conductometric soot sensing, current conductometric sensors are power intensive (5-30 W) and slow (60-170 s between sensing cycles) due to their large size, ineffective thermal insulation, and the high currents required for soot combustion (when self-regenerating). We propose to use microelectromechanical systems (MEMS) fabrication methods to develop a miniaturized conductometric soot sensor with a built-in polysilicon microheater for self-regeneration, whose small size and good thermal isolation make it a fast and energy-effective sensor. Preliminary results show that the sensor has 100-1000 times lower power consumption and 2-5 times faster self-regeneration than current sensors, consuming 20-40 mW per sensing cycle and self- regenerating in <30 s. Sensor performance in an internal combustion engine and catalyst integration to lower the regeneration temperature are currently being tested.
Contact Information ameyarao@berkeley.edu, maboudia@berkeley.edu, carraro@yahoo.com
Advisor Roya Maboudian

 
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NanoPlasmonics, Microphotonics & Imaging
Project IDBPN786 New Project
Project Title NanoPlasmonics for Sensing and Energy
Status New
Funding Source Fellowship
Keywords
Researchers Arthur O. Montazeri
Abstract Controlling and concentrating infrared radiation has the potential to significantly impact infrared sensors, thermal imaging devices, as well as heat conversion systems. As most molecules have vibrational modes in the infrared range, they reradiate a great portion of the incident radiation instead of efficiently transmitting it. As a promising alternative, plasmonic gratings not only offer low-loss transmission of infrared radiation, but also compress the long infrared wavelengths. This localization effect greatly improves the sensing resolution and offers high-intensity fields at scales much smaller than the infrared wavelengths in free space. Such high intensities are invaluable probes for revealing light-matter interaction in nanoscale dimensions previously inaccessible. The challenge of creating low-loss materials in the infrared has been a nano-engineering feat utilizing functional gradients to guide and localize radiation. Recent advancements in nanofabrication, as well as a deeper understanding of light-matter interaction, have led to the realization of these plasmonic light-trapping gratings. We show the applicability of these structures as sensors for 1- detecting infrared signatures of molecules, 2- imaging, including bio-imaging, 3-concentrating thermal infrared radiation for energy harvesting. Our proposed structures utilize a gradient in the strength of plasmonic coupling between surfaces in close proximity to each other. Using this technique it is possible to fabricate such surfaces which possess a uniform depth and can be mass-produced using nano-imprint techniques.
Contact Information arthur.montazeri@berkeley.edu
Advisor Roya Maboudian, Carlo Carraro

 
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Table of Projects
NanoTechnology: Materials, Processes & Devices
Project IDBPN790 New Project
Project Title Low power microheater based sensing platform for breath analysis
Status New
Funding Source Industry
Keywords
Researchers Hu Long, Anna Harley-Trochimczyk
Abstract Breath analysis is attractive since it is noninvasive and can be repeated frequently for monitoring human physiological conditions. The ability to analyze human breath on mobile platforms would enable a noninvasive method of providing important health information to individuals. Here, we report the integration of semiconducting metal oxides on a microheater- based sensing platform to achieve fast, sensitive, selective, and stable breath analysis. We have developed a sensitive CO sensor by in situ growth of porous SnO2 films on a low power microheater. The sensor can detect 10 ppm CO with less than 0.2 sec response and recovery times at room temperature. Moreover, for the first time, we use MoS2 aerogel nanomaterial to detect NO2 at room temperature, and obtain a detection limit of 500 ppb, which is comparable to the results reported for single or few-layer MoS2 but follows much more scalable synthesis and device fabrication processes. Current work is focusing on improving sensing performance by low temperature heating and metal nanoparticle modification.
Contact Information longhu@berkeley.edu, anna.harleytr@berkeley.edu
Advisor Roya Maboudian, Carlo Carraro, Willi Mickelson

 
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NanoTechnology: Materials, Processes & Devices
Project IDBPN762
Project Title Microheater-Based Platform for Low Power Combustible Gas Sensing
Status Continuing
Funding Source NSF
Keywords chemical sensing, combustible gas sensing, microheater, aerogel
Researchers Anna Harley-Trochimczyk, Jiyoung Chang
Abstract Accurate detection of flammable gases is essential for safe operation of many industrial processes. Installing networks of combustible gas monitors in industrial settings can allow for rapid leak detection and increased safety and environmental protection. However, existing combustible gas monitors are not suitable for use in wireless sensor networks due to the high power consumption. We have developed an ultra-low power combustible gas sensor with competitive sensitivity and lifetime characteristics that will enable ubiquitous wireless monitoring of combustible gases in industrial settings, resulting in enhanced safety. The core technology is a suspended microheater coated with a novel nanotechnology-based sensing material that catalyzes hydrocarbon combustion. Hydrogen gas sensing has been demonstrated with ~10 mW of power required to reach operation temperatures using platinum nanoparticles on a graphene aerogel support. Recently, propane sensing using the same material has been shown, but the graphene aerogel is not thermally stable at the required temperatures, so further research will look at other nanoparticle support options. Palladium nanoparticles are also under investigation for hydrogen and hydrocarbon sensing in order to enable arrays of sensing material for better selectivity.
Contact Information anna.harleytr@berkeley.edu
Advisor Roya Maboudian, Willi Mickelson, Alex Zettl

 
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Table of Projects
Physical Sensors & Devices
Project IDBPN424
Project Title Silicon Carbide Nanomaterials for Harsh Environment Applications
Status Continuing
Funding Source NSF
Keywords Silicon Carbide, LPCVD, Nanowires, RF MEMS, Harsh Environment, Supercapacitors
Researchers Lunet E. Luna
Abstract Silicon Carbide (SiC) is a material of interest to fabricate sensors and actuators able to operate in harsh environments. Particularly, its mechanical and electrical stability and its chemical inertness make SiC well suited for designing devices capable of operation in high temperature and corrosive environments. Harsh-environment stable metallization remains one of the key challenges with SiC technology. We are developing novel metallization schemes, utilizing solid-state graphitization, to improve the long-term reliability of Pt/Ti/poly-SiC contacts in high temperature environments. Our metallization scheme, which also includes an alumina protection layer, exhibits low contact resistivity after 500 hours at 450 °C in air. In addition, we are investigating the growth mechanism of SiC nanowires to understand how growth parameters may be manipulated to achieve specific SiC nanowire properties. The ability to control SiC nanowire polytype, growth orientation, and shape is essential for obtaining specific optical and electronic nanowire characteristics. SiC nanowires with tailored properties are attractive candidates for applications requiring high surface area coupled with extreme physicochemical stability, such as high- temperature energy storage, field emission cathodes, gas sensing in harsh environment, and electrowetting applications.
Contact Information lunet@berkeley.edu
Advisor Roya Maboudian, Carlo Carraro

 
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Wireless, RF & Smart Dust
Project IDBPN767
Project Title MEMS-Based Tunable Channel-Selecting Super-Regenerative RF Transceivers
Status New
Funding Source DARPA
Keywords MEMS, Oscillators, Radio, Transceiver
Researchers Tristan Rocheleau, Thura Lin Naing
Abstract This project aims to achieve low-power micromechanical-based tunable RF channel- selecting transceivers.
Contact Information tristan@eecs.berkeley.edu, thura@eecs.berkeley.edu
Advisor Clark T.-C. Nguyen

 
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Table of Projects
Wireless, RF & Smart Dust
Project IDBPN359
Project Title Micromechanical Disk Resonator-Based Oscillators
Status Continuing
Funding Source DARPA
Keywords MEMS, Oscillators
Researchers Thura Lin Naing, Tristan Rocheleau
Abstract This project aims to build and test micromechanical-based frequency synthesizer components that meet or exceed the requirements of the GSM standard. Towards these goals, the project investigates short and long-term stability of MEMS-based oscillators, particularly, phase noise and acceleration sensitivity. In addition to providing a highly accurate, on-chip frequency reference, a fully-integrated oscillator can achieve greater stability (particularly acceleration sensitivity) and far less power consumption than any comparable off-chip oscillator. In the process of achieving a fully-integrated frequency synthesizer, much of the research is expected to focus on development of integrated resonators-ASIC oscillators, as well as other needed components such as MEMS-based frequency dividers.
Contact Information thura@eecs.berkeley.edu, tristan@eecs.berkeley.edu
Advisor Clark T.-C. Nguyen, Elad Alon

 
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Table of Projects
Wireless, RF & Smart Dust
Project IDBPN540
Project Title Temperature-Stable Micromechanical Resonators and Filters
Status Continuing
Funding Source Industry
Keywords µmechanical resonator, electrical stiffness, compensation, frequency drift
Researchers Alper Ozgurluk
Abstract This project aims to suppress temperature-induced frequency shift in high frequency micromechanical resonators targeted for channel-select filter and oscillator applications. A novel electrical stiffness design technique is utilized to compensate for thermal drift, in which a temperature-dependent electrical stiffness counteracts the resonator’s intrinsic dependence on temperature caused mainly by Young’s modulus temperature dependence.
Contact Information ozgurluk@eecs.berkeley.edu, ctnguyen@eecs.berkeley.edu
Advisor Clark T.-C. Nguyen

 
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Package, Process & Microassembly
Project IDBPN734
Project Title Package-Derived Influences on Micromechanical Resonator Stability
Status Continuing
Funding Source Fellowship
Keywords vacuum, encapsulation, hermetic, package, stress, finite element analysis
Researchers Divya N. Kashyap
Abstract Vacuum encapsulation of RF disk and beam resonators is necessary in order to maintain high Q and frequency stability. However, the difference in the coefficient of thermal expansion of the package material and the substrate lead to package induced stress. This project aims to explore the effects of this stress on the frequency response of the resonators using finite element analysis (FEA) software. Simulations performed on resonators packaged using conventional hermetic encapsulation techniques such as anodic and fusion bonding will be compared to that of an in situ packaging method where the resonators are housed in a polysilicon shell.
Contact Information dnk003@eecs.berkeley.edu
Advisor Clark T.-C. Nguyen

 
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Table of Projects
Physical Sensors & Devices
Project IDBPN534
Project Title Fully-Integrated Micromechanical Clock Oscillator
Status Continuing
Funding Source DARPA
Keywords Oscillator, 32kHz, RTC, Real Time Clock, Fully Integrated MEMS
Researchers Henry G. Barrow
Abstract This project aims to develop a fully integrated micromechanical clock oscillator which outperforms current quartz-based clock oscillators in terms of both size and cost. A 32-kHz micromechanical resonator with a temperature coefficient better than 10 ppm over the commercial temperature range will act as the oscillator's reference. In addition, this oscillator will utilize an integrated fabrication process above modern transistor circuits in order to minimize device footprint and production expense.
Contact Information hbarrow@berkeley.edu
Advisor Clark T.-C. Nguyen

 
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Wireless, RF & Smart Dust
Project IDBPN707
Project Title Automated Passband Tuning of High-Order Microelectromechanical Filters
Status Continuing
Funding Source DARPA
Keywords MEMS, micromechanical, filter, high-order, bandpass, rolloff, stopband, rejection
Researchers Henry G. Barrow
Abstract This project aims to develop multi-resonator micromechanical electronic filters for use in communication systems requiring bandpass filters with sharp rolloffs and large stopband rejections. A complete analysis of the design, fabrication and testing of filters comprised of 2-8 micromechanical resonators coupled by flexural mode springs will establish a greater understanding this exciting MEMS device. In addition, the implementation of an automated tuning scheme will provide complete corrective control over the filter’s passband by negating the effects of fabrication error.
Contact Information hbarrow@berkeley.edu
Advisor Clark T.-C. Nguyen

 
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Physical Sensors & Devices
Project IDBPN433
Project Title A Micromechanical Power Converter
Status Continuing
Funding Source DARPA
Keywords Power Converter, MEMS Switch
Researchers Ruonan Liu
Abstract The overall goal of this project is to demonstrate a switched-mode power converter (e.g., a charge pump) using micromechanical switching elements that allow substantially higher voltages and potentially higher conversion efficiencies than transistor-switch based counterparts.
Contact Information liur@eecs.berkeley.edu
Advisor Clark T.-C. Nguyen

 
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Physical Sensors & Devices
Project IDBPN435
Project Title A Micromechanical Power Amplifier
Status Continuing
Funding Source DARPA
Keywords MEMS switch, switching mode power amplifier, MEMS resonator
Researchers Wei-Chang Li
Abstract This overall project aims to demonstrate methods for amplifying signals with higher efficiency compared to transistor circuitry using strictly mechanical means for ultra-low-power signal processing applications.
Contact Information wcli@eecs.berkeley.edu
Advisor Clark T.-C. Nguyen

 
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Table of Projects
Wireless, RF & Smart Dust
Project IDBPN682
Project Title Strong I/O Coupled High-Q Micromechanical Filters
Status Continuing
Funding Source BSAC Member Fees
Keywords
Researchers Robert A. Schneider
Abstract This project improves the Q-factors of piezoelectric aluminum nitride (AlN) resonators by detaching their electrodes and suspending them at close distance. These devices are then used to make high-Q filters. "Capacitive-piezo" transduction, as it is called, allows for simultaneous low motional impedance (10-1000 Ohm) and high-Q (Q>8,800) performance for AlN resonators at VHF and UHF frequencies. The main advantage of these devices over capacitive resonators is their much stronger electromechanical coupling, e.g., Cx/C0>1.0%, enabling kt^2*Q figures of merit exceeding those of other technology classes in the range of 100MHz-1GHz. This project aims to use these high-performance resonators to demonstrate self-switchable, low impedance channel-selecting filters. Such filters can operate with insertion losses of less than 2-dB, stop- band rejection exceeding 50-dB, and power handling capability for high out-of-band and in-band power.
Contact Information bschneid@eecs.berkeley.edu
Advisor Clark T.-C. Nguyen

 
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Wireless, RF & Smart Dust
Project IDBPN676
Project Title Q-Boosted Optomechanical Oscillators
Status Continuing
Funding Source DARPA
Keywords
Researchers Turker Beyazoglu, Tristan Rocheleau
Abstract This project aims to demonstrate Radiation Pressure driven Optomechanical Oscillators (RP-OMOs) with low phase noise and low power operation suitable for various applications in optical and RF communications. In particular, chip scale atomic clocks with low power consumption can be realized by replacing its power-hungry quartz-based microwave synthesizer with the proposed RP-OMO structure. The Q-boosted RP-OMO design approach of this work makes it possible to optimize both optical and mechanical design to simultaneously reduce the phase noise and threshold power of these oscillators while providing electromechanical coupling for electrical output and voltage controlled frequency tuning, as needed for the intended CSAC application.
Contact Information turker@eecs.berkeley.edu
Advisor Clark T.-C. Nguyen, Ming C. Wu

 
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Wireless, RF & Smart Dust
Project IDBPN701
Project Title Bridged Micromechanical Filters
Status Continuing
Funding Source DARPA
Keywords Micromechanical Filters, High-order Filters,
Researchers Jalal Naghsh Nilchi
Abstract The overall project aims to explore the use of bridging between non-adjacent resonators to generate loss poles in the filter response toward better filter shape factor, sharper passband-to- stopband roll-off and better stopband rejection.
Contact Information jalal.naghsh.nilchi@berkeley.edu
Advisor Clark T.-C. Nguyen

 
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Wireless, RF & Smart Dust
Project IDBPN709
Project Title Tunable & Switchable Micromechanical RF Filters
Status Continuing
Funding Source DARPA
Keywords micromechanical resonators, RF filters, channel selection
Researchers Lingqi Wu
Abstract This project aims to explore the use of on-chip capacitively transduced micromechanical resonators to realize RF filters with substantial size and performance advantages. With their extremely high quality factor in UHF range and strong coupling coefficient enabled by nanometer electrode-to-resonator gap spacings, capacitive-gap transduced micromechanical resonators should be able to realize reconfigurable RF channel select filters for future cognitive radio applications.
Contact Information wulingqi@berkeley.edu
Advisor Clark T.-C. Nguyen

 
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Wireless, RF & Smart Dust
Project IDBPN683
Project Title OpenWSN: A Standards-Based Low-Power Wireless Development Environment
Status Continuing
Funding Source Federal
Keywords Wireless Sensor Networks, Protocol Stack, Ultra Low Power, Embedded systems, 802.15.4e, 6TiSCH, RPL, 6LoWPAN, CoAP
Researchers Nicola Accettura
Abstract The OpenWSN project is an open-source implementation of a fully standards-based protocol stack for capillary networks, rooted in the new IEEE802.15.4e Time Synchronized Channel Hopping standard. The novel IETF 6TiSCH protocols make IEEE802.15.4e TSCH perfectly interfaced with well-known Internet-of-Things IETF standards, such as 6LoWPAN, RPL and CoAP, thus enabling ultra-low power and highly reliable mesh networks which are fully integrated into the Internet. The resulting protocol stack will be cornerstone to the upcoming Machine-to-Machine revolution. OpenWSN is ported to numerous commercial available platforms from older 16-bit micro-controller to state-of-the-art 32-bit Cortex-M architectures. The tools developed around the low- power mesh networks include visualization and debugging software, a simulator to mimic OpenWSN networks on a PC, and the environment needed to connect those networks to the Internet. OpenWSN projects leads standardization efforts for ultra low power M2M networks while contributing with innovative protocols for scalable, distributed and energy efficient communications.
Contact Information nicola.accettura@eecs.berkeley.edu, pister@eecs.berkeley.edu
Advisor Kristofer S.J. Pister

 
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Wireless, RF & Smart Dust
Project IDBPN789 New Project
Project Title Reconfigurable, Wearable Sensors to Enable Long-Duration Circadian Biomedical Studies
Status New
Funding Source Fellowship
Keywords Biomedical monitoring, wearable sensors, biological rhythms, translational health metrics
Researchers David C. Burnett
Abstract The last 10 years have seen the emergence of wearable personal health tracking devices as a mainstream industry; however, they remain limited by battery lifetime, specific sensor selection, and a market motivated by a focus on short- term fitness metrics (e.g., steps/day). This hampers the development of a potentially much broader application area based on optimization around biomedical theory for long-term diagnostic discovery. As new biometric sensors come online, the ideal platform enabling the gathering of long-term diagnostic data would have the built-in extensibility to allow testing of different sensor combinations in different research settings to discover what kinds of data can be most useful for specific biomedical applications. Here we present the first generation of a reconfigurable wrist-mounted sensor device measuring 7x4x2cm and weighing 51g with battery (29g without). In its current configuration, it has recorded skin temperature, acceleration, and light exposure; these three variables allow prediction of internal circadian rhythms, as an example of the application of biological theory to enhance pattern detection. This generation is capable of operating long-term with minimal day-to-day disruption via easily exchangeable batteries, and has enough space for several months of data sampling to gather long-term diagnostic metrics. Future developments will include the addition of energy scavenging and a wireless mesh network for ambient data collection, the combination of which will allow uninterrupted data to be gathered without depending on the user.
Contact Information db@eecs,berkeley.edu
Advisor Kristofer S.J. Pister

 
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Wireless, RF & Smart Dust
Project IDBPN744
Project Title Self-Destructing Silicon
Status Continuing
Funding Source DARPA
Keywords
Researchers Joseph Greenspun, Osama Khan, Travis Massey, Brad Wheeler
Abstract Funded under the DARPA Vanishing Programmable Resources (VaPR) program, this project explores the fundamental issues associated with making wireless sensor nodes disappear after they have achieved their goal. Near-term goals include electro-chemical dissolution of circuit wiring, and in-package XeF2 etch of the silicon substrate. The ultimate goal is to demonstrate a single-chip wireless mote capable of self-destruction on receipt of specific RF command or environmental change.
Contact Information ksjp@berkeley.edu, brad.wheeler@berkeley.edu, greenspun@eecs.berkeley.edu, oukhan@berkeley.edu, maha
Advisor Kristofer S.J. Pister, Michel M. Maharbiz

 
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Wireless, RF & Smart Dust
Project IDBPN735
Project Title Autonomous Microrobotic Systems
Status Continuing
Funding Source BSAC Member Fees
Keywords Microrobotics, electrostatics, actuators, MEMS, autonomous sensors
Researchers Daniel Contreras, Daniel Drew, Brad Wheeler, David Burnett, Joseph Greenspun, Michael Lorek
Abstract Recent advances in MEMS technology have enabled a new generation of microrobotic engineering applications. This project aims at developing micro-scale actuation and transduction mechanisms for mobility. Currently, electrostatic inchworm motors in conjunction with microfabricated leg linkages are being investigated for walking while atmospheric ion thrusters are investigated for flying. A motivation behind this research is the development of truly mobile, high resolution, and autonomous sensor networks. One of the key elements towards autonomy is the fusion of these mobility mechanisms with energy harvesting capabilities, including high-voltage solar arrays. In addition, ultra-low power control and communications platforms must be designed with the constraints of a microrobotic system in mind.
Contact Information dscontreras@eecs.berkeley.edu
Advisor Kristofer S. J. Pister

 
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Physical Sensors & Devices
Project IDBPN768
Project Title Plug-Through Energy Monitor for Wall Outlet Electrical Devices
Status New
Funding Source BSAC Member Fees
Keywords energy monitor, wireless, 802.15.4, plug load
Researchers Michael C. Lorek
Abstract This project focuses on the development of a Plug-Through Energy Monitor (PTEM) for electrical devices connected to wall outlets. Using a non-intrusive inductive current sensing technique, the load current can be measured without requiring a series sensing element that breaks the circuit. This enables slim profile sensing hardware, and eliminates the power dissipated across series elements as in traditional current measurement techniques. This work aims to design a PCB-based solution that measures load current & line voltage, accurately calculates real power dissipated by a plug load, and reports its information using 802.15.4 wireless technology. Careful system-level optimization is required to minimize component costs, mitigate unwanted 60 Hz noise coupling, and maintain a small PCB footprint. We hope a low-cost device such as this will enable the widespread adoption of electrical energy metering in building wall outlets.
Contact Information mlorek@eecs.berkeley.edu
Advisor Kristofer S.J. Pister

 
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Physical Sensors & Devices
Project IDBPN705
Project Title Standard CMOS-Based, Fully Integrated, Stick-On Electricity Meters for Building Sub-Metering
Status Continuing
Funding Source Federal
Keywords
Researchers Michael C. Lorek
Abstract We propose the development and testing of a system of technologies to minimize the installed cost of electricity sub-metering in buildings. This system utilizes non-contact, self-calibrating voltage and current sensors and wireless communication to eliminate the need for installation by an electrician, installation of conduit and enclosures, and installation of wired communication infrastructure. Electricity sub-metering is a critical component for continuous commissioning, fault detection and diagnosis, demand response, and other energy efficiency opportunities.
Contact Information mlorek@eecs.berkeley.edu
Advisor Kristofer S.J. Pister, Steven Lanzisera

 
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Physical Sensors & Devices
Project IDBPN608
Project Title FM Gyroscope
Status Continuing
Funding Source Federal
Keywords gyroscope, calibration
Researchers Yu-Ching Yeh, Burak Eminoglu
Abstract MEMS gyroscopes for consumer devices, such as smartphones and tablets, suffer from high power consumption and drift which precludes their use in inertial navigation applications. Conventional MEMS gyroscopes detect Coriolis force through measurement of very small displacements on a sense axis, which requires low-noise, and consequently high-power, electronics. The sensitivity of the gyroscope is improved through mode-matching, but this introduces many other problems, such as low bandwidth and unreliable scale factor. Additionally, the conventional Coriolis force detection method is very sensitive to asymmetries in the mechanical transducer because the rate signal is derived from only the sense axis. Parasitic coupling between the drive and sense axis introduces unwanted bias errors which could be rejected by a perfectly symmetric readout scheme. This project develops frequency modulated (FM) gyroscopes that overcome the above limitations. FM gyroscopes also promise to improve the power dissipation and drift of MEMS gyroscopes. We present results from a prototype FM gyroscope with integrated CMOS readout electronics demonstrating the principle.
Contact Information ycyeh@eecs.berkeley.edu, eminoglu@eecs.berkeley.edu
Advisor Bernhard E. Boser

 
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BioMEMS
Project IDBPN649
Project Title Magnetic Particle Flow Cytometer
Status Continuing
Funding Source BSAC Member Fees
Keywords magnetic flow cytometry
Researchers Pramod Murali, Vikram Iyer
Abstract The complex susceptibility of magnetic materials show a frequency dependent behavior. The goal of the work over the last six months has been to measure the susceptibility for diff erent magnetic materials.
A coplanar waveguide is designed on a Duroid substrate. The waveguide is connected to a spiral inductor of nominal value 4.5 nH. These devices are wire bonded to the CPW and measurements are carried out using a network analyzer. The susceptibility is extracted from the measured S-parameters.
Measurement results show a clear difference between the susceptibility curves of ferrites of cobalt, manganese and nickel. These measurements corroborate the design of a CMOS chip for detection of magnetically labelled cells enabling a point of care cytometer.
Contact Information pramodm@eecs.berkeley.edu
Advisor Bernhard E. Boser

 
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BioMEMS
Project IDBPN685
Project Title Real-Time Intraoperative Fluorescent Imager for Microscopic Residual Tumor in Breast Cancer
Status Continuing
Funding Source NIH
Keywords cancer, imaging, radiation, surgery, breast cancer, oncology
Researchers Efthymios P. Papageorgiou
Abstract Successful treatment of early stage cancer depends on the ability to resect both gross and microscopic disease. Microscopic residual disease (MRD) can lead to increased risk for local recurrence (LR) and reduced overall survival. Currently no methods exist to intraoperatively assess whether individual cancer cells remain in the tumor bed; only post-operative pathologic evaluation of the tumor for molecular tumor markers, requiring several days in a laboratory setting, can definitely identify MRD. Over 50,000 women each year who are diagnosed with breast cancer are found to have MRD after lumpectomy. Elimination of MRD in breast cancer is known to reduce the need for second surgical procedures, halve the LR rate from 30% to 15%, and increase breast cancer survival. A method of imaging MRD intraoperatively to guide complete resection is therefore essential. This project seeks to develop one method for intraoperatively identifying MRD.
Contact Information epp@berkeley.edu, anwarme@radonc.ucsf.edu
Advisor Bernhard E. Boser, Mekhail Anwar

 
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Physical Sensors & Devices
Project IDBPN722
Project Title Pulse-Echo Ultrasonic Fingerprint Sensor on a Chip
Status Continuing
Funding Source BSAC Member Fees
Keywords Fingerprints, fat, body-index, ultrasonic, MEMS, integrated circuits
Researchers Hao-Yen Tang, Yipeng Lu
Abstract The proliferation of electronic devices such as smartphones creates a pressing need for reliable biometric authentication. Present solutions such as capacitive fingerprint sensors have failed to gain wide acceptance due to their susceptibility to contamination from oils, perspiration, and dirt. Ultrasonic fingerprint sensors solve these problems but currently available devices are too large and costly for deployment in consumer devices. This motivates us to design a small-volume and fully-integrated ultrasonic fingerprint sensor using a monolithic CMOS-MEMS process to overcome the disadvantage of current commercial ultrasonic fingerprint sensors. The prototype consist of a 24x8 array within 2mm x 0.8mm area is able to image real fingerprint, and a 5mm x 4mm second version is under fabrication.
Contact Information b96901108@eecs.berkeley.edu
Advisor Bernhard E. Boser

 
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NanoPlasmonics, Microphotonics & Imaging
Project IDBPN665
Project Title Frequency Modulated Laser Source for 3D Imaging
Status Continuing
Funding Source DARPA
Keywords Photonics, LADAR, LIDAR, MEMS Tuning, EOPLL, Optoelectronics, Ranging
Researchers Behnam Behroozpour, Phillip Sandborn
Abstract In recent years we have seen a growing demand for 3D cameras for applications such as gaming, entertainment, and autonomous vehicles. Present solutions suffer from high power dissipation and large size. This project leverages heterogeneous integration of standard CMOS electronics with high performance optical components including lasers, photo-diodes, interferometers and waveguides to reduce size, cost, and power dissipation.
Contact Information behroozpour@berkeley.edu, sandborn@eecs.berkeley.edu
Advisor Bernhard E. Boser, Ming C. Wu, Eli Yablonovitch, Connie J. Chang-Hasnain

 
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Physical Sensors & Devices
Project IDBPN764
Project Title Untethered Stress-Engineered MEMS MicroFlyers
Status Continuing
Funding Source State
Keywords
Researchers Spencer Ward, Ameen Hussain, Vahid Foroutan, Ratul Majumdar
Abstract In this project, we are developing and testing microscale flying structures, called Microflyers. The microflyers consist of a 300 µm × 300 µm sized chassis fabricated from polycrystalline silicon using surface micromachining. At present, the flyers are levitated using microfabricated heaters attached to an underlying substrate. A novel, in-situ masked post-release stress-engineering process is used to generate a concave upwards curvature of the flyers chassis, causing static pitch and roll stability during flight, take-off, and landing. The initial experiments have demonstrated stable levitation. The microflyers represent an attractive airborne reconnaissance platform due to their microscale size, and thus stealth operation.
Contact Information SpencerWard@cal.berkeley.edu, shussa50@uic.edu , vforou2@uic.edu, rmajum2@uic.edu
Advisor Igor Paprotny

 
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Wireless, RF & Smart Dust
Project IDBPN392
Project Title Mobile Airborne Particulate Matter Monitor for Cellular Deployment
Status Continuing
Funding Source Industry
Keywords MEMS, Wireless, Particulates, Sensor, Mobile
Researchers Dorsa Fahimi, Omid Mahdavipour, Seiran Khaledian
Abstract This project involves optimization of a portable MEMS-based instrument that quantifies and differentiates fine airborne particulate matter concentrations of such substances as diesel engine exhaust, environmental tobacco smoke, and wood smoke. The goal of the project is integration with and interfacing of the instrument to a cellular telephone for mobile monitoring.
Contact Information seiran.kh@gmail.com, dfahim2@uic.edu, omahda2@uic.edu, rwhite@eecs.berkeley.edu, paprotny@uic.edu, l
Advisor Richard M. White, Lara Gundel, Igor Paprotny

 
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Physical Sensors & Devices
Project IDBPN738
Project Title Sensor Instrumentation to Improve Safety of U.S. Underground Coal Mines
Status Continuing
Funding Source Federal
Keywords coal mine, wireless sensor network, sensing inertness, data rate, power supply
Researchers Pit Pillatsch, Omid Mahdavipour
Abstract Coal mining is recognized as a dangerous undertaking. Explosions of coal dust and gases that may exist underground (such as methane) are well-known hazards, in addition to which are unexpected structural collapses. In order to prevent the propagation of coal dust explosions, regulations require that inert rock dust is applied in underground areas of a coal mine. This project is aimed at creating real-time sensors to determine the explosibility of a coal and rock dust mixture and to communicate the results from inside the mine to safety personnel above ground.
Contact Information paprotny@uic.edu, rwhite@eecs.berkeley.edu, pwright@me.berkeley.edu, ppillatsch@berkeley.edu, omahda
Advisor Richard M. White, Igor Paprotny, Paul K. Wright, Lara Gundel

 
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Physical Sensors & Devices
Project IDBPN697
Project Title Natural Gas Pipeline Research
Status Continuing
Funding Source State
Keywords Gas, pipeline, sensor, pressure, flow, vibration, methane, wireless, ultrasonic, laser, weld, crack
Researchers Son Duy Nguyen, Pit Pillatsch
Abstract The goal is to develop technologies for natural gas pipelines that provide increased system awareness and reliability, lower system costs, better assessment of pipeline integrity, and provide tangible benefits for utility customers. The benefits sought are natural gas pipelines that are more reliable, efficient, and secure. The BSAC research can be divided into three areas: 1. Microfabricated MEMS natural gas sensors 2. Low-power wireless sensor communication infrastructure 3. Ultrasonic diagnostic and test devices for natural gas pipelines.
Contact Information nguyen.duyson@berkeley.edu, rwhite@eecs.berkeley.edu, paprotny@uic.edu
Advisor Richard M. White, Paul K. Wright, Igor Paprotny

 
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Wireless, RF & Smart Dust
Project IDRMW29
Project Title Electric Power Sensing for Demand Response
Status Continuing
Funding Source State
Keywords demand response, magnetic field, voltage sensor, current sensor, piezoelectric, smart dust
Researchers Christopher Sherman
Abstract The overarching goal of this UCB project is to identify and develop technology to enable more-effective use of electric power. This phase has primarily focused on the development of small, inexpensive, low-power proximity-based sensors for voltage and current monitoring for better granularity of monitoring at multiple levels of the power grid (distribution, customer, and individual appliances). The term 'demand response' (DR) refers to the ability of electricity users to respond automatically to time- and location-dependent electric energy price and supply contingency information in order to tailor their electric energy usage.
Contact Information ctsherman@berkeley.edu, rwhite@eecs.berkeley.edu
Advisor Richard M. White, Paul K. Wright

 
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Microfluidics
Project IDBPN787 New Project
Project Title 3D-Printed Molds for Rapid Assembly of PDMS-based Microfluidic Devices
Status New
Funding Source Fellowship
Keywords 3D Printing, Microfluidics, PDMS
Researchers Casey C. Glick, Joseph Lin, William Zhuang, Mitchell Srimongkol, Aaron Schwartz, Panitan Satamalee, Dennis Tekell, Judy Kim, Caroline Su
Abstract In this work, we demonstrate the use of 3D-printed molds for fabricating PDMS-based microfluidic devices. 3D Printing allows for the fabrication of molds that are not monolithic in structure, and therefore represents a significant improvement over the capabilities of standard soft lithography; with 3D-printed molds, we can fabricate most features commonly generated by soft lithography in addition to formerly difficult features such as domes and variable-sized channels. Furthermore, we demonstrate that this technique can be used to generate microfluidic devices molded on both sides - which allows for single-step generation of features like vias and thin membranes - and can be easily adapted to generate multi-layer microfluidic structures.
Contact Information cglick@berkeley.edu
Advisor Liwei Lin

 
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Microfluidics
Project IDBPN774
Project Title 3D Printed Integrated Microfluidic Circuitry
Status New
Funding Source BSAC Member Fees
Keywords Lab-on-a-Chip, 3D Printing, Microfluidics,
Researchers Eric Sweet, Sunita Venkatesh, Kjell F. Ekman, Ashley Tsai, Kevin Korner
Abstract In President Barack Obama’s 2013 State of the Union Address, he remarked that 3D printing-based manufacturing could change “the way we make almost everything.” Similar to the way in which the shift from vacuum tube-based technologies to solid-state components transformed the field of electronics, the shift from standard “top-down” fabrication methods (e.g., soft lithography) to emerging “bottom-up” micro/nanoscale 3D printing processes could revolutionize both chemical and biological fields.
Contact Information ericsweet2@gmail.com, sunitav@berkeley.edu, kfekman@berkeley.edu, ashleytsai@berkeley.edu, kevin_kor
Advisor Liwei Lin, Luke P. Lee, Ryan D. Sochol

 
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Microfluidics
Project IDBPN775
Project Title Integrated Microfluidic Circuitry via Optofluidic Lithography
Status New
Funding Source BSAC Member Fees
Keywords Lab-on-a-Chip, Microfluidics, Optofluidic Lithography,
Researchers Pranjali Beri, Anish Khare, Kevin Korner
Abstract Mechanical engineering methods and microfabrication techniques offer powerful means for solving biological challenges. In particular, microfabrication processes enable researchers to develop technologies at scales that are biologically relevant and advantageous for executing biochemical reactions. Here, optofluidic lithography-based methodologies are employed to develop autonomous single-layer microfluidic components, circuits, and systems for chemical and biological applications.
Contact Information pranjalib@berkeley.edu, anishkhare@gmail.com, kevin_korner@berkeley.edu, rsochol@mit.edu
Advisor Liwei Lin, Luke P. Lee, Ryan D. Sochol

 
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Microfluidics
Project IDBPN706
Project Title Single-Layer Microfluidic Gain Valves via Optofluidic Lithography
Status Continuing
Funding Source Fellowship
Keywords microfluidic, gain, valve
Researchers Casey C. Glick, Christopher Deeble, Ki Tae Wolf, Vishnu Jayaprakash
Abstract This project aims to create single-layer microfluidic gain valves for use in microfluidic devices. Autonomous microfluidic devices are essential for the long-term development of versatile biological and chemical platforms; however, the challenges of creating effective control mechanisms – e.g., the need for variable pressure sources, signal degradation in cascaded devices, and multi-stage manufacture methods – have proven considerable. Using in situ optofluidic lithography, we develop a single-layer pressure-based valve system with a static gain greater than unity. We will demonstrate the device in several microfluidic circuits, including logic gates and amplifiers. These pressure gain-based systems will enable microfluidic devices with a wide range of applications, such as flow rectifiers, oscillators, and high-precision pressure measurements. Due to ease of manufacture and design flexibility, this valve design could have widespread Lab-on- a-Chip applications by enabling self-regulation of microfluidic devices.
Contact Information cglick@berkeley.edu, lwlin@me.berkeley.edu
Advisor Liwei Lin

 
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Micropower
Project IDBPN782 New Project
Project Title Direct-write nanofibers for flexible energy storage
Status New
Funding Source Army/ARL
Keywords Direct-write nanofibers, flexible electronics, energy storage, supercapacitor
Researchers Caiwei Shen
Abstract Solid-state flexible micro supercapacitors based on porous and conducting polymer nanofibers via the direct-write, near-field electrospinning process have been constructed. Testing results have shown a capacitance of 0.3mF/cm2, 30X larger as compared with those of flat electrodes. Key innovations of this work include: (1) densely-packed, porous 3D nanostructures with conductive nanofibers via the near-field electrospinning process; (2) flexible solid-state micro electrodes with high energy density using the pseudocapacitive effect; and (3) simple yet versatile manufacturing process compatible with various substrates and surfaces. As such, this technology is readily available to make practical MEMS energy storage devices.
Contact Information shencw10@berkeley.edu
Advisor Liwei Lin

 
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Physical Sensors & Devices
Project IDBPN784 New Project
Project Title Aluminum Gallium Nitride 2DEG Sensors and Devices
Status New
Funding Source BSAC Member Fees
Keywords GaN, AlGaN, 2DEG, sensor, MEMS
Researchers Kaiyuan Yao
Abstract Two dimensional electron gas (2DEG) and hole gas (2DHG) can be induced at the interface of epitaxial AlGaN/GaN due to spontaneous and piezoelectric polarization. Such electronic system features high transport mobility, carrier density and piezoelectric sensitivity. Mechanical strain and vibrations of devices can be transduced to electronic signals in embeded 2DEG for further processing. In this project, we study physical properties of this strongly-coupled electromechanical system, and develop possible devices such as pressure sensor, MEMS resonator, ultrasonic transducer, etc.
Contact Information kyyao@berkeley.edu
Advisor Liwei Lin

 
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NanoTechnology: Materials, Processes & Devices
Project IDBPN736
Project Title Atomic Layer Deposition Ruthenium Oxide Supercapacitors
Status New
Funding Source Industry
Keywords Atomic layer deposition, supercapacitor, energy storage
Researchers Roseanne H. Warren
Abstract This work presents the first demonstration of atomic layer deposition (ALD) ruthenium oxide (RuO2) and its conformal coating onto vertically aligned carbon nanotube (CNT) forests as supercapacitor electrodes. Specific accomplishments include: (1) successful demonstration of ALD RuO2 deposition, (2) uniform coating of RuO2 on a vertically aligned CNT forest, and (3) an ultra-high specific capacitance of 100 mF/cm2 from prototype electrodes with a scan rate of 100 mV/s. Advantages of the ALD method include precise control of the RuO2 layer thickness and composition without the use of CNT- binder molecules. In addition to high capacitance, preliminary results indicate that the ALD RuO2- CNTs have good stability over repeated cycling. Besides its use in supercapacitors, ALD-RuO2 has potential NEMS applications: in biosensors and pH sensing, as a strong oxidative material in multiple chemical processes, and in catalytic reactions for photocatalytic systems.
Contact Information warrenr@berkeley.edu
Advisor Liwei Lin

 
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NanoTechnology: Materials, Processes & Devices
Project IDBPN672
Project Title Solar Hydrogen Production by Photocatalytic Water Splitting
Status Continuing
Funding Source KAUST
Keywords Solar energy, photocatalysis, nano materials
Researchers Roseanne H. Warren, Emmeline Kao
Abstract Hydrogen is a promising, environmentally-friendly fuel source for replacing fossil fuels in transportation and stationary power applications. Currently, most hydrogen is produced from non-renewable sources including natural gas, oil, and coal. Photoelectrochemical (PEC) water splitting is a new renewable energy technology that aims to generate hydrogen from water using solar energy. When light is absorbed by the photocatalyst, an electron-hole pair is generated that interacts with water molecules in a surface reduction-oxidation reaction to decompose the water into hydrogen and oxygen. The current challenge in PEC water splitting is finding low-cost, stable materials with good visible light absorption and high efficiency for water splitting. Silicon has demonstrated promising capabilities as photocatalysts due to its high visible light absorption, low cost, and high abundance. This project aims to improve the performance of silicon for water splitting by developing new high-surface area silicon photoelectrodes using chemical vapor deposition silicon.
Contact Information warrenr@berkeley.edu
Advisor Liwei Lin

 
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Micropower
Project IDBPN737
Project Title Graphene-Based Microliter-Scale Microbial Fuel Cells
Status Continuing
Funding Source BSAC Member Fees
Keywords
Researchers Vishnu Jayaprakash, Roseanne Warren, Casey Glick
Abstract Microbial fuel cells (MFCs) are energy harvesters that use the anaerobic respiration of microorganisms to generate electricity. With the increase in demand for micro-scale, low power output energy harvesters over the last five years, microliter-scale microbial fuel cells (µMFCs) have received a great deal of scientific interest. Previously, researchers have operated these fuel cells under controlled anodic conditions to attain high current densities and columbic efficiencies. However, relatively low power outputs, inadequate working potentials, complex fabrication processes and tedious operating techniques have limited µMFCs from implementation in practical applications. To improve such performance and enhance the practicality of these fuel cells, this project presents new fuel cell architectures, electrode materials, fabrication techniques and operating procedures.
Contact Information soorse@berkeley.edu
Advisor Liwei Lin

 
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Micropower
Project IDBPN742
Project Title 3D Carbon-Based Materials for Electrochemical Applications
Status Continuing
Funding Source BSAC Member Fees
Keywords
Researchers Xining Zang
Abstract Carbon-based materials such as CNT (1D) and graphene (2D) have been widely studied as electrode materials in various applications, including sensing, catalyst and energy storage. The extraordinary properties of these carbon-based materials provide possible advantages in reduced reaction potential, low surface fouling, and large surface area. This project aims to investigate possible combination of the 1D and 2D carbon-based materials in the form of 3D structures. The possible new structure could exhibit the following desirable characteristics: 1) conformal deposition with ordered 3D CNT/graphene structures; 2) high surface area with active surfaces; 3) feasibility of embedding other catalysts for electrochemical reactions. The long term goals are to optimize the 3D graphene/CNT materials both structurally and functionally for applications in electrochemical sensors, catalysts, and energy storage devices.
Contact Information xining.zang.me@berkeley.edu
Advisor Liwei Lin

 
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Physical Sensors & Devices
Project IDBPN743
Project Title Highly Responsive pMUTs
Status Continuing
Funding Source BSAC Member Fees
Keywords Piezoelectric Micromachined Ultrasonic Transducers (pMUTs), curved pMUTS, spherical piezoelectric elastic shells, bimorph pMUTs, dual electrode bimorph pMUT
Researchers Sina Akhbari
Abstract Ultrasonic imaging is one of the most important and widely used medical imaging techniques, which uses high-frequency sound waves to view soft tissues such as muscles, internal organs as well as blood flowing through blood vessels in real time. With the advancement of microelectromechanical systems (MEMS), ultrasonic devices operated based on plate flexural mode have shown remarkable improvements in bandwidth, cost, and yield over the conventional thickness- mode PZT sensors. MEMS fabrication technologies can be utilized to realize both capacitive (cMUTs) and piezoelectric (pMUTs) micromachined ultrasonic transducers However, these devices could enjoy much more widespread applications if they were adjustable, better focused with lower energy requirements. This project aims to highly responsive pMUTs based on CMOS compatible fabrication processes with the potential to replace the plate-based pMUTs for high electromechanical coupling ultrasonic transducer arrays for applications in fingerprint IDs, body movement sensors, and hand- held medical imagers
Contact Information sina.akhbari68@gmail.com
Advisor Liwei Lin

 
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Wireless, RF & Smart Dust
Project IDBPN574
Project Title On-Chip Micro-Inductor
Status Continuing
Funding Source Industry
Keywords Inductor, On-Chip, RF
Researchers Kisik Koh, Chen Yang
Abstract On-chip inductors are key passive elements to high-power and radio frequency (RF) integrated circuits (ICs). This project aims to realize super-compact on-chip micro-inductor with magnetic media for high-power and RF IC's, including: 1) to explore low-loss, high resonance frequency magnetic material for inductor application; 2) to develop magnetic-material integration process; 3) to realize the super-compact magnetic-embedded inductor. The long-term objectives for this project are to resolve the current problem of lacking compact-size high-performance on-chip inductors, and then reduces the whole circuit cost significantly and helps the practical realization of RF systems-on-a- chip (SoCs) for real-world applications.
Contact Information kskoh@berkeley.edu, chenyang@berkeley.edu, lwlin@me.berkeley.edu
Advisor Liwei Lin

 
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Physical Sensors & Devices
Project IDBPN772
Project Title Graphene for Flexible and Tunable Room Temperature Gas Sensors
Status Continuing
Funding Source Federal
Keywords Chemical Sensor, Gas Sensor, Graphene FET, Selectivity
Researchers Yumeng Liu
Abstract As air pollution from industrial and automobile emission becomes more and more severe, the personalized, integrated gas sensor is desirable for everyone to monitor everyday's air quality as well as their personal health condition. Such sensor should have the desirable features like energy efficient,miniature size, accurate response (down to ppm level), flexibility and selectivity. Traditional 3D semiconductor based gas sensor works in the temperature range of 300 to 400 oC, which requires large amount of energy to power the heater. We here propose using graphene based flexible field effect transistor to detect and distinguish gas in both concentration and category concurrently by measuring its electrical properties at room temperature.
Contact Information yumengliu@berkeley.edu
Advisor Liwei Lin

 
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Microfluidics
Project IDBPN778 New Project
Project Title Single-cell MicroRNA Quantification for Gene Regulation Heterogeneity Study
Status New
Funding Source Foundation
Keywords Single-cell, microRNA, microfluidics, amplification method
Researchers Qiong Pan, Xianjin Xiao, Soongweon Hong
Abstract MicroRNAs can affect individual cells’ epigenetic modifications in a variety of biological processes such as cell cycle regulation, apoptosis, cell differentiation and maintenance of stemness. These modifications can be largely heterogeneous depending on the internal and external factors. However, traditional tube-based qPCR or microarray system is lack of sensitivity and requires intensive labor and time input. Current integrated single-cell miRNA detection platforms are lack of the capacity of handling thousands of cells at the same time for statistical meaningful data acquisition. Here, we established a high throughput single-cell miRNA quantification method based on microfluidic flow cell technology and novel n2 amplification in replacement of PCR. The advantages of this method are: • Single-cell addressability: Reliable single-cell trapping and miRNA capturing within isolated microchambers ensures clearly readable signals from single cells. • Higher throughput: process more than 5000 single cells’ target miRNA level in one operation. • More precise and faster quantification than PCR: Instead of real-time PCR, we developed an n2 isothermal amplification method that enables precise quantification of miRNA using snapshots of single-time-point signals within 35mins. • Fast and easy cell-to-signal results: By using a picoliter-reactor array in flow cell format, whole process of sample preparation is easily completed by capillary flow within 15 mins. The cell-to-signal process takes less than 1 hour. • Good flexibility: Time dependent perfusion and stimulation of captured single-cells is available on the spot of analysis; protein and miRNA correlation study is available within one set of experiment by combining with protein detection. This method is promising in the use of fast screening of miRNA candidates. We have quantified heterogeneous distribution of single- cell miRNAs in human breast cancer cell line MCF-7 and its doxorubicin- resistant population. The results showed miRNA sub- populations and their changes upon drug treatment. Furthermore, we detected the correlation between miRNAs and the transcription factor NANOG in genetically modified mouse embryonic stem cells (mESCs). The result indicated that several miRNAs may contributes to the heterogeneous distribution of NANOG among mESCs as downstream regulators of NANOG.
Contact Information qiongpan@berkeley.edu
Advisor Luke P. Lee

 
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Microfluidics
Project IDBPN794 New Project
Project Title Bubble-free Microfluidic PCR
Status New
Funding Source Foundation
Keywords Bubble-free microfluidic PCR chip, polymerase chain reaction, rapid microfluidic PCR
Researchers Sanghun Lee
Abstract Polymerase chain reaction (PCR) is one of the most important analytical methods in fundamental molecular biology, life science, medicine, environmental and agricultural monitoring due to its specificity and quantification capability. However, the major problems of microfluidic PCR on chip are the generation of bubbles, reagent evaporation, and the needs of external equipment. Here, we report the theoretical analysis, design, fabrication and characterization of bubble- free microfluidic digital PCR on chip for a rapid sample-to-answer molecular diagnostic platform. After the theoretical modeling of bubble formation and suppression, we accomplish the bubble-free microfluidic digital PCR on chip. Using an integrated polymeric microfabrication method, we achieve ultrafast PCR in less than 3 min. For the applications of bubble-free microfluidic digital PCR on chip in molecular diagnostics, we demonstrate the successful amplification of cMET gene, a NA biomarker for lung cancer. This approach will result in a new paradigm for ultrafast molecular diagnosis and can facilitate broad availability of NA-based diagnostics for point-of-care testing, personalized medicine, preventive medicine, and prevention of drug resistance.
Contact Information sanghun.lee@berkeley.edu; lplee@berkeley.edu
Advisor Luke P. Lee

 
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NanoTechnology: Materials, Processes & Devices
Project IDBPN727
Project Title On-Chip Single Molecule miRNA Detection for Cancer Diagnosis
Status Continuing
Funding Source Industry
Keywords miRNA, Detection, Cancer
Researchers Julian A. Diaz, Sang Hun Lee
Abstract Early stage cancer diagnosis may mean the difference between a successful or an ineffective treatment. Therefore, development of methods that allow the detection of premature signatures of cancer are necessary. Mature microRNAs are short non-coding RNAs strands (~18-21 nt) involved in gene regulation of eukaryotic cells. In cancer cells some miRNAs appear over or under expressed, and serve as a markers to signal the presence of these malignancies. MicroRNAs, however, are present in very low concentrations, thus sensitive and multiplexed methods that detect specific miRNAs are needed to enable the patient with timely and better treatment of this disease. Currently, we are developing a method that offers sensitive, fast, and multiplexed detection of miRNAs in blood samples. This method can be easily adapted to chip technology paving the way to recognize miRNAs without the need of either sample preparation or enzymatic/chemical modification. Due to the multiplexed and sensitive capabilities of our device, we also expect it to provide accurate cancer type characterization.
Contact Information jdiaz1@berkeley.edu
Advisor Luke P. Lee

 
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Microfluidics
Project IDBPN773
Project Title Human Induced Pluripotent Stem Cell-derived Hepatocytes (hiPSC-HPs)-based Organs on Chip
Status Continuing
Funding Source NIH
Keywords Microlfuidics, Organ-on-a-chip, Drug development, microsystems, Tissue engineering
Researchers Alireza Salmanzadeh
Abstract Three major barriers inhibit current research in human drug screening: experimental in vivo interventions in people have unacceptable risks; in vitro models of human tissue are primitive; and, non-human animal models are not directly comparable to humans. However, currently there is no in vitro platform that recapitulates physiological microenvironments using human induced pluripotent stem cells (hiPSC). Here we demonstrated hiPSC-derived hepatocytes (hiPSC-HPs)-based organs on chip, consisting of three functional components: a cell culture pocket, an endothelium-like perfusion barrier, and a nutrient transport channel acting as a capillary. A high fluidic resistance-based microfluidic endothelium-like barrier physically separates the cell culture and nutrient transport compartments. Our design allows continuous perfusion, high-throughput formation of microtissue amenable to continuous monitoring and sampling by determining a set of device parameters and cell seeding options. Cell loading was optimized to achieve high cell density and viability (>95%) right after seeding into microdevices. We also found that a high cell concentration (~10 million cells/mL) was critical for high loading quality. We validated and tested the hiPSC-HPs- based liver-on-a-chip platform for long-term functionality of the liver tissue (4 weeks), by measuring hepatocytes Albumin secretion, in the absence of coculturing with non-parenchymal cells. Also hiPSC-HPs are co-cultured with fibroblasts, T3T-J2 cells, to enhance the longevity of hepatocytes to more than 4 weeks. It was confirmed that the model is suitable for drug toxicity screening and validates the liver tissue model’s response by investigating Cytochromes P450 (CYPs) enzymes activities, specifically CYP 3A4 and 1A2, the most active drug metabolizing CYPs, using Promega P450-Glo™ Assays. Our liver-on-a-chip platform addresses the need of having a suitable in vitro liver model recapitulating the physiological functions and drug responsiveness of the liver for drug development, and disease modeling applications.
Contact Information alirezas@berkeley.edu, lplee@berkeley.edu
Advisor Luke P. Lee

 
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Microfluidics
Project IDBPN730
Project Title Microfluidic Blood Plasma Separation for Point-of-Care Diagnostics
Status Continuing
Funding Source Foundation
Keywords Microfluidic, Blood plasma separation, Point-of-care
Researchers Jun Ho Son, Sang Hun Lee, ByungRae Cho
Abstract Microfluidic lab-on-a-chip (LOC) device for point-of-care (POC) diagnostics have been widely developed for the rapid detection of infectious diseases such as HIV, TB and Malaria. Blood plasma separation is an initial step for most blood-based diagnostics. Although, centrifuge method is the classical bench- top technique, it is time and labor intensive, and therefore, automation and integration of blood plasma separation in the LOC device is ideal for POC diagnostics. Here, we propose a novel microfluidic blood plasma separation device for POC diagnostics. This investigation will hopefully lead to a simple and reliable blood plasma separation device that can be utilized by individuals with minimal training in resource-limited environments for POC diagnostics. This blood plasma separation device will be integrated with downstream detection module for single-step POC diagnostics.
Contact Information jhson78@berkeley.edu, sanghun.lee@berkeley.edu, brcho@berkeley.edu, lplee@berkeley.edu
Advisor Luke P. Lee

 
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NanoPlasmonics, Microphotonics & Imaging
Project IDBPN791 New Project
Project Title Integrated Photobioreactor with Optical Excitation Membranes (iPOEMs) for Efficient Photosynthetic Light Harvesting
Status New
Funding Source Foundation
Keywords Photobioreactor, Nanoplasmonics, Selective wavelength scattering, Microalgae, Biofuel
Researchers Doyeon Bang
Abstract Efficient photosynthetic light harvesting came into the spotlight due to the growing concerns on global energy crisis. However, non-uniform distribution of light in photobioreactor is one of major challenges for efficient photosynthetic light harvesting. We developed an integrated photobioreactor with optical excitation membranes (iPOEMs) by creating uniform optical antennas and scattering network in a flexible membrane. We demonstrated that iPOEMs are stable under temperature change (>80 ⁰C and <0 ⁰C) or illumination of intensive light (>50 mW/cm2). We developed iPOEMs with pillar structures for uniform light distribution and selective scattering of blue (c.a. 380-440 nm) and red light (c.a. 640-680 nm) to facilitate growth of microalgae and avoid the photoinhibiton of photosynthesis. We obtained the enhanced growth of microalgae in high population by using the iPOEMs with pillar structures. We believe our iPOEMs will shed new light on the accomplishment of efficient photosynthetic light harvesting.
Contact Information doyeonbang@berkeley.edu
Advisor Luke P. Lee

 
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Microfluidics
Project IDBPN679
Project Title Portable Microfluidic Pumping System for Point-Of-Care Diagnostics
Status Continuing
Funding Source Fellowship
Keywords point-of-care, diagnostics, microfluidic, rapid test, isothermal, amplification, pumping, pump, degas, vacuum
Researchers Erh-Chia Yeh
Abstract It is desirable for medical diagnostic assays to have portable and low cost pumping schemes. Although capillary loading is the most common example, it cannot load dead-end channels, often have fibres that obstruct optics, and have surface treatment or geometrical constraints. On the other hand, conventional degas pumping lacks flow control, speed, and reliability. Here we report a new portable pumping system that does not require any peripheral equipment or external power sources/controls. Compared with conventional degas pumping, it has ~8 times less standard deviation in speed, is operational for >2 hours, can tune and increase loading speed up to 10 times, and can maintain a slower exponential decay of flow rate (factor of 5 increase in time constant). As an example, we show it was possible to integrate this pumping system with one-step sample prep and digital amplification, and demonstrated quantitative detection of DNA in one-step (10~10^5 copies DNA/μl). We believe this integrated power-free pumping design may become a fundamental building block for future point-of-care diagnostic devices.
Contact Information erh-chia-yeh@berkeley.edu
Advisor Luke P. Lee

 
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NanoPlasmonics, Microphotonics & Imaging
Project IDBPN703
Project Title Directly Modulated High-Speed nanoLED Utilizing Optical Antenna Enhanced Light Emission
Status Continuing
Funding Source Federal
Keywords nano-photonics, optical antenna, photonics, optical interconnect, nanotechnology, optoelectronics, plasmonics
Researchers Seth A. Fortuna, Michael Eggleston
Abstract Coupling an optical antenna to a nanoscale light emitter has been shown to increase the spontaneous emission rate by compensating for the large size mismatch between the emitter and emission wavelength. This spontaneous emission rate enhancement has been predicted to be as large as several orders of magnitude, easily surpassing the stimulated emission rate and enabling high direct modulation bandwidths. The aim of this project is to utilize this concept to demonstrate a directly modulated nanoscale semiconductor light emitting diode (nanoLED) with modulation speeds in excess of 10s of GHz, exceeding the bandwidth of semiconductor lasers. Unlike lasers, such nanoLEDs are also inherently low-power and do not require minimum threshold current density for operation and are therefore a promising light generating source for use, for example, in intra-chip communication.
Contact Information fortuna@eecs.berkeley.edu
Advisor Ming C. Wu

 
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NanoPlasmonics, Microphotonics & Imaging
Project IDBPN721
Project Title MEMS-Electronic-Photonic Heterogeneous Integration (MEPHI) Component Fabrication, Design, and Characterization
Status Continuing
Funding Source DARPA
Keywords optical phase-locked loop, silicon photonics, 3D integration, MEMS, CMOS, VCSEL, HCG, PIC, FMCW LADAR,
Researchers Phillip A.M. Sandborn, Behnam Behroozpour, Sangyoon Han
Abstract Active III-V photonic components and passive Si photonic circuits are integrated with CMOS electronic circuits in this project. The modular MEMS-Electronic-Photonic Heterogeneous Integration (MEPHI) platform will make use of the high performance of the individual components and integrate (1) MEMS tunable VCSEL with high-index-contrast grating (HCG) mirrors, (2) photodetectors, (3) Si photonic waveguides, couplers, and interferometers, (4) high-efficiency vertical optical coupler between III-V and Si waveguides, and (5) CMOS circuits for frequency control and temperature compensation. In order to demonstrate the capabilities of the proposed MEPHI platform, a frequency- modulated continuous-wave laser detection and ranging (FMCW LADAR) source is being developed. Results have shown that electronic-photonic 3D integration of optoelectronic components can greatly improve the performance of FMCW LADAR sources. We also demonstrate that optoelectronic integration improves the bandwidth of optical phase-locked loops (OPLLs).
Contact Information sandborn@berkeley.edu
Advisor Ming C. Wu

 
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NanoPlasmonics, Microphotonics & Imaging
Project IDBPN788 New Project
Project Title Optical Phased Array for LIDAR
Status New
Funding Source Industry
Keywords
Researchers Youmin Wang
Abstract We have previously demonstrated the development of an Optical Phased Array (OPA) micromechanical system (MEMS) used for beam steering, which shows great advantages over previous mechanisms such as opto-mechanical, acoustooptical (AO) or electro-optical (EO). Supported by Texas Instruments (TI), we aim to integrate the OPA MEMS system into the application of automobile navigation, which is currently primarily dominated by opto-mechanical scanning based systems. Opto-mechanical scanning devices are usually bulky and relatively slow, while competing technologies (AO, EO) utilize devices that while small in size, cannot provide the steering speeds and versatility necessary for many applications. In drawing from phased array concepts that revolutionized RADAR technology by providing a compact, agile alternative to mechanically steered technology, the OPA based LIDAR program seeks to integrate thousands of closely packed optical emitting facets, precise relative electronic phase control of these facets, and all within a very small form factor. Comparing with other competing LIDAR system, the OPA based LIDAR system will have multiple degrees of freedom for phase control which enables not only agile beam steering but also beam forming and multiple beam generation, greatly expanding the diversity of applications.
Contact Information wu@eecs.berkeley.edu
Advisor Ming C. Wu

 
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NanoPlasmonics, Microphotonics & Imaging
Project IDBPN751
Project Title 50x50 Silicon Photonic MEMS Switch with Microsecond Response Time
Status Continuing
Funding Source DARPA
Keywords optical switch, large scale, fast, small footprint
Researchers Sangyoon Han, Tae Joon Seok, Niels Quack, Wencong Zhang
Abstract We developed a new architecture suitable for building a large-scale optical switch with fast response time. We have demonstrated switches with scale of 50x50, and speed of 2.5us using our new architecture. The switch architecture consists of optical crossbar network with MEMS actuated couplers and it is implemented on silicon photonics platform. Thanks to high integration density of silicon photonics platform, we could integrate 50x50 switch on area less than 1cm x 1cm. We belive that our switch architecture can be scaled up to the scale larger than 200x200 and beyond.
Contact Information sangyoon@eecs.berkeley.edu
Advisor Ming C. Wu

 
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NanoPlasmonics, Microphotonics & Imaging
Project IDBPN609
Project Title Ultra-Sensitive Photodetectors on Silicon Photonics
Status Continuing
Funding Source NSF
Keywords phototransistor, silicon photonics, metal-optics
Researchers Ryan Going, Tae Joon Seok
Abstract As CMOS devices shrink in physical size, electrical interconnects between the devices will consume an ever-greater proportion of total chip power. A promising solution is to use silicon photonics for intra- and inter-chip communications. To be cost effective, both the optical transmitter and receiver should be made small, highly efficient, and CMOS compatible. Shrinking the photodiode will increase sensitivity and energy efficiency, but as it gets very small, the capacitance of the wire to the first amplifying stage in the receiver becomes significant. We present a solution which integrates the photodiode and first stage transistor in the form of an integrated germanium phototransistor. The rapid melt growth technique is used to integrate high quality single crystal germanium onto a silicon waveguide integrated device in a CMOS process. Bipolar gain combined with extremely compact device dimensions produces high-speeed, high-sensitivity receivers which operate at 1550 nm on a silicon photonics platform.
Contact Information rwgoing@berkeley.edu
Advisor Ming C. Wu

 
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NanoPlasmonics, Microphotonics & Imaging
Project IDBPN458
Project Title Optical Antenna-Based nanoLED
Status Continuing
Funding Source Federal
Keywords Plasmonics, Laser, Light Emitting Diode, Nanophotonics, Nanocavity, Optical Interconnects, Transition Metal Dichalcogenides
Researchers Kevin Han, Michael Eggleston, Sujay Desai, Seth Fortuna
Abstract Spontaneous emission has been considered slower and weaker than stimulated emission. As a result, light-emitting diodes (LEDs) have only been used in applications with bandwidth < 1 GHz. Spontaneous emission is inefficient because the radiating dipole is much smaller than wavelength and such short dipoles are poor radiators. By attaching an optical antenna to the radiating dipole at the nanoscale, the emission rate can be significantly increased enabling high modulation bandwidths theoretically >100 GHz. This project focuses on the physical demonstration of this new type of nanophotonic device. Current fabrication and experimental results of devices using transition metal dichalcogenides (TMDs) as an emitter material will be presented. Fundamental limits of rate enhancement will also be discussed.
Contact Information kyh@eecs.berkeley.edu
Advisor Ming C. Wu, Ali Javey

 
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Microfluidics
Project IDBPN552
Project Title Light-Actuated Digital Microfluidics (Optoelectrowetting)
Status Continuing
Funding Source BSAC Member Fees
Keywords Digital Microfluidics, Droplet Microfluidics, Electrowetting, Optoelectrowetting, EWOD, Optofluidics
Researchers Shao Ning Pei, Jodi Loo
Abstract The ability to quickly perform large numbers of chemical and biological reactions in parallel using low reagent volumes is a field well addressed by droplet-based digital microfluidics. Compared to continuous flow-based techniques, digital microfluidics offers the added advantages such as individual sample addressing and reagent isolation. We are developing a Light- Actuated Digital Microfluidics device (also known as optoelectrowetting) that optically manipulates nano- to micro-liter scale aqueous droplets on the device surface. The device possesses many advantages including ease of fabrication (no lithography required) and the ability for real-time, reconfigurable, large-scale droplets control (simply by altering the low-intensity projected light pattern). We hope to develop Light-Actuated Digital Microfluidics into a powerful platform for lab- on-a-chip (LOC) applications.
Contact Information shaoning@eecs.berkeley.edu
Advisor Ming C. Wu

 
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Microfluidics
Project IDBPN733
Project Title Optoelectronic Tweezers for Long-Term Single Cell Culture
Status New
Funding Source BSAC Member Fees
Keywords Optoelectronic tweezers, OET, single cell, single cell analysis
Researchers Shao Ning Pei, Tiffany Dai
Abstract In contrast to bulk analysis, analyzing biological samples on a single-cell level is a powerful tool in deriving a more complete, quantitative understanding of cellular behavior. The optoelectronic tweezers (OET) platform utilizes light-generated dielectrophoretic force to manipulate micro-scale objects reconfigurably on the device surface. Consequently, OET is able to select for individual cells and manipulate them into a specific configuration where these cells are cultured and studied for an extended period of time. Compared to trap-based single-cell techniques, the OET platform provides advantages such as specific selection of an individual cell and subsequent culturing over a larger-scale area at a particular address on the surface of the device. We are looking to apply the OET platform for long- term culture of single cells and gain useful insights into topics such as rate of proliferation, differentiation, and changes in morphology and protein expression.
Contact Information shaoning@eecs.berkeley.edu
Advisor Ming C. Wu, Song Li

 
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Package, Process & Microassembly
Project IDBPN354
Project Title The Nanoshift Concept: Innovation through Design, Development, Prototyping and Fabrication of MEMS, Microfluidics, Nano and Clean Technologies
Status Continuing
Funding Source Industry
Keywords Nanoshift, nanolab, microlab, process, recharge, commercial
Researchers Ning Chen, Salah Uddin
Abstract Nanoshift LLC is a privately held research and development company specializing in MEMS, Microfluidics and Nano technologies. Nanoshift provides high quality customizable services for device and process design, research and development, rapid prototyping, low volume fabrication and technology transfer into high volume. Typical projects come from academia, government and industry. Nanoshift is the solution for your device concept to commercialization needs. Nanoshift collaborates with BSAC to make industry-leading development resources available for all BSAC members while improving BSAC's visibility and funding.
Contact Information nchen@nanoshift.net, suddin@nanoshift.net
Advisor John M. Huggins

 
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Package, Process & Microassembly
Project IDBPN712
Project Title Bridging Research-to-Commercialization Gaps In an Industry/ University Ecosystem
Status Continuing
Funding Source NSF
Keywords Commercialization, Industry, Nanoshift, NSF, MIG, Nanolab, Intermediaries, Gas Sensor, Wireless, Wireless HART, ChemFET
Researchers John Huggins, Hossain M. Fahad, Hiroshi Shiraki, David Burnett, Nicola Accettura
Abstract Some BSAC members have, in our surveys and at IAB meetings, vocalized that we need to help bridge commercialization gaps and increase the speed of commercialization. Traditional University research commercialization paths through passive licensing to start-ups, are often highly successful and will remain the dominant path. But such paths do not leverage the sophisticated manufacturing, marketing, and sales channels of our larger Industrial members who could rapidly exploit certain research discoveries. While any such commercialization facilitation programs cannot compromise the fundamental research mission of the Center, new proactive development models are sought. This project and the new model involves joint efforts of multiple Industrial members with specialized or focused non-University agents (intermediaries) who can facilitate the transition from laboratory proof of concept vehicles to precommercial prototypes to commercial production. The intermediaries provide boundary spanning between university research and commercialization, including active participation in formalized multi-industrial participant university-based research projects with specific transition plans to industrial partners.
Contact Information jhuggins@berkeley.edu
Advisor John M. Huggins, Ali Javey, Kristofer S.J. Pister

 
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Physical Sensors & Devices
Project IDBPN655
Project Title Materials for High Quality-Factor Resonating Gyroscopes
Status Continuing
Funding Source DARPA
Keywords MEMS gyroscopes, inertial sensors, surface micromachining, High Q materials, CVD diamond
Researchers Hadi Najar, Chen Yang
Abstract This project will investigate new materials suitable for achieving Q-factors in excess of 1 million in resonating gyroscopes. Experimental studies of dissipation caused by thermoelastic and surface losses will be performed using resonator test structures. The effect of doping and microstructure is explored on CVD diamond MEMS resonators. Hundreds of surface micromachined cantilevers and double-ended tuning fork (DETF) resonators were fabricated in nanocrystalline diamond (NCD) and microcrystalline diamond (MCD) films deposited using hot filament CVD technique with varying levels of Boron doping, Deposition temperature and methane flow rate. Thermal conductivities of diamond films were measured using TDTR technique for further mapping of theory and experiment. The dissipation mechanisms were further explored over temperature range from 300-730 Kelvin.
Contact Information dahorsley@ucdavis.edu, hnajar@ucdavis.edu, chenyang@berkeley.edu
Advisor David A. Horsley

 
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Physical Sensors & Devices
Project IDBPN781 New Project
Project Title 3-Axis MEMS Gyroscope
Status New
Funding Source BSAC Member Fees
Keywords
Researchers Soner Sonmezoglu, Parsa Taheri-Tehrani
Abstract The goal of the project is to design the resonator and electronics for a single structure 3-Axis MEMS vibratory rate gyroscope. The mechanical structure of the device will be designed to have the capability of 3-Axis sensing performance. Low-power CMOS electronics will be designed to meet the requirements for consumer electronics.
Contact Information ssonmezoglu@ucdavis.edu, ptaheri@ucdavis.edu
Advisor David A. Horsley

 
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Physical Sensors & Devices
Project IDBPN603 New Project
Project Title Micro Rate-Integrating Gyroscope
Status Continuing
Funding Source DARPA
Keywords MEMS, Rate Integrating Gyroscope, Silicon Wet Etch, Diamond, Control
Researchers Chen Yang, Hadi Najar, Parsa Taheri-Tehrani
Abstract The goal of this project is to realize a micro rate-integrating gyroscope that produces an output signal proportional to rotation angle rather than rotation rate. If successful, this device would eliminate the need of integrating the gyroscope's rate output to obtain the angle. Realizing a micro rate-integrating gyroscope can be achieved by fabricating hemispherical resonating shells with extremely close frequency matching (delta f < 10 Hz) and a very high quality factor (Q > 1 million). Structures must be highly axisymmetric and micro-finished to nanometer scale roughness. Gyroscope resonators have at least two resonant modes that can be coupled by Coriolis force. Difference in damping coefficients and stiffness of the resonant modes of the MEMS resonator known as anisodamping and anisoelasticity are main sources of error in RIG. Control algorithms should be developed to eliminate these errors.
Contact Information dahorsley@ucdavis.edu, chenyang@berkeley.edu, hnajar@ucdavis.edu, ptaheri@ucdavis.edu
Advisor David A. Horsley

 
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Physical Sensors & Devices
Project IDBPN684
Project Title Integrated Microgyroscopes with Improved Scale-Factor and Bias Stability
Status Continuing
Funding Source DARPA
Keywords gyroscope, inertial sensor, signal processing, CMOS
Researchers Jason Su, Sarah Nitzan
Abstract Despite their small size, low power dissipation, and low cost, the large bias and scale factor errors of current MEMS inertial sensors preclude using them for dead reckoning navigation. Although these shortcomings can be overcome with precision manufacturing and extensive calibration, such solutions suffer from high cost and secondary effects such as long term drift. Presently, the use of in-situ calibration techniques in MEMS sensors is limited to the electronic interfaces, where they are instrumental for reducing drift arising from electronic components. This project extends the benefit of electronic background calibration to the MEMS transducer to continuously reduce scale factor and bias errors arising from manufacturing tolerances and drift.
Contact Information dahorsley@ucdavis.edu, sarah.nitzan@gmail.com, thssu@ucdavis.edu
Advisor David A. Horsley

 
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Physical Sensors & Devices
Project IDBPN599
Project Title MEMS Electronic Compass: Three-Axis Magnetometer
Status Continuing
Funding Source Federal
Keywords
Researchers Vashwar T. Rouf, Soner Sonmezoglu
Abstract The goal of this is project is to develop a low-power three axis MEMS magnetic sensor suitable for use as an electronic compass in smart phones and portable electronics. Our objective is to achieve a resolution of 200 nT/rt Hz and power consumption of 5 mW/axis with DC power supply of 3.3V. To enable co-integration with a 3-axis accelerometer, we seek to optimize sensor performance without the need for a vacuum seal. Although past devices designed by our group have demonstrated that our resolution goal is reachable, these devices suffered from dc offset larger than Earth's field and required an external programmable oscillator for operation. Here, we aim to reduce offset by two orders of magnitude and develop self-oscillation loops to excite the sensor at its natural frequency.
Contact Information vtrouf@ucdavis.edu,dahorsley@ucdavis.edu,ssonmezoglu@ucdavis.edu
Advisor David A. Horsley

 
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Physical Sensors & Devices
Project IDBPN785 New Project
Project Title Scandium-doped AlN for MEMS
Status New
Funding Source BSAC Member Fees
Keywords
Researchers Qi Wang
Abstract The goal of this project is to design, fabricate and characterize novel MEMS devices based on scandium-doped AlN thin films. Scandium-doped AlN thin film is a promising piezoelectric material due to its CMOS compatible process, low relative permittivity and high piezoelectric coefficient. It enables better performance for piezoelectric MEMS devices.
Contact Information dahorsley@ucdavis.edu, qixwang@ucdavis.edu
Advisor David A. Horsley

 
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Physical Sensors & Devices
Project IDBPN466
Project Title Air-Coupled Piezoelectric Micromachined Ultrasound Transducers
Status Continuing
Funding Source DARPA
Keywords Aluminum Nitride, Piezoelectric, Ultrasound Transducers, MEMS
Researchers Ofer Rozen
Abstract Characterize air-coupled aluminum nitride piezoelectric micromachined ultrasound transducers (pMUTs) for use in range finding and gesture recognition applications. MEMS Aluminum Nitride (AlN) piezoelectric sensor technology has been chosen due to the relatively simple deposition process and compatibility with CMOS technology which enables the potential integration of the sensor and drive electronics on the same chip. Guided by both analytic and finite element models the optimum design parameters are chosen to obtain the desired resonant frequency, bandwidth, and maximum output sound pressure for the transmitter, and maximum sensitivity for the receiver. We are currently exploring several conceptual designs, using different fabrication processes, to improve robustness while maintaining the performance.
Contact Information orozen@ucdavis.edu
Advisor David A. Horsley

 
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Physical Sensors & Devices
Project IDBPN628
Project Title Novel Ultrasonic Fingerprint Sensor Based on High-Frequency Piezoelectric Micromachined Ultrasonic Transducers (PMUTs)
Status Continuing
Funding Source BSAC Member Fees
Keywords piezoelectric, ultrasound transducers, medical imaging, fingerprint sensors
Researchers Yipeng Lu, Stephanie Fung, Qi Wang, Hao-Yen Tang
Abstract The goal of this project is to design and fabricate a novel ultrasonic fingerprint sensor based on high-frequency Piezoelectric Micromachined Ultrasonic Transducers (PMUTs). Present fingerprint sensors in portable devices, such as capacitive fingerprint sensors, have failed to gain wide acceptance due to their susceptibility to contamination from oils, perspiration and dirt. Ultrasonic fingerprint sensors solve these problems, but devices currently available are too large and costly for deployment in consumer devices. Here, an ultrasonic fingerprint sensor based on PMUTs fully integrated with CMOS ASIC is proposed and demonstrated. 1-D pulse-echo imaging of steel phantom using 20×8 PMUT array with electronic scanning is demonstrated with echo voltage amplitude ~150 mV. 2-D pulse-echo imaging of PDMS fingerprint phantom with ~600 um pitch similar to human fingerprint pattern is demonstrated.
Contact Information yplu@ucdavis.edu, dahorsley@ucdavis.edu
Advisor David A. Horsley

 
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Physical Sensors & Devices
Project IDBPN780 New Project
Project Title Impedance Spectroscopy to Monitor Fracture Healing
Status New
Funding Source NSF
Keywords
Researchers Monica C. Lin
Abstract An estimated 7.9 million fracture injuries occur each year in the United States. Of these, 10% of fractures result in delayed or non-union, with this number rising to 46% when they occur in conjunction with vascular injury. Current methods of monitoring include taking X-rays and making clinical observations. However, radiographic techniques lag and physician examination of injury is fraught with subjectivity. No standardized methods exist to assess the extent of healing that has taken place in a fracture, revealing the need for a diagnostic device that can reliably detect non-union in its early pathologic phases. Electrical impedance spectroscopy has been used to characterize different tissues, and we hypothesize that this technique can be applied to fractures to distinguish between the various types of tissue present in the clearly defined stages of healing. We are developing an objective measurement tool that utilizes impedance spectroscopy to monitor fracture healing, with the goal of providing physicians with more information that can resolve the initial stages of fracture healing. This would enable early intervention to prevent problem fractures from progressing to non-union.
Contact Information monica.lin@berkeley.edu
Advisor Michel M. Maharbiz

 
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Physical Sensors & Devices
Project IDBPN714
Project Title Impedance Sensing Device to Monitor Pressure Ulcers
Status Continuing
Funding Source NSF
Keywords Wound Healing, Impedance Spectroscopy
Researchers Amy Liao, Monica C. Lin
Abstract Chronic cutaneous wounds affect millions of people each year and take billions of dollars to treat. Formation of pressure ulcers is considered a "never event" - an inexcusable, adverse event that occurs in a healthcare setting. Current monitoring solutions (pressure-distributing beds, repositioning patients every few hours, etc) are very expensive and labor intensive. In response to this challenge, we are developing a novel, flexible monitoring device that utilizes impedance spectroscopy to measure and characterize tissue health, thus allowing physicians to objectively monitor progression of wound healing as well as to identify high-risk areas of skin to prevent formation of pressure ulcers. Previous studies that examined the dielectric response of cell suspensions and tissues have identified several distinct dispersions associated with particular molecular-level processes that can be used to distinguish between tissue types. We are utilizing impedance spectroscopy to detect subtle changes in tissue, enabling objective assessment and providing a unique insight into the condition of a wound. Wireless capability can be implemented to allow for remote monitoring. In parallel, efforts are being made to transfer this technology onto resorbable substrates to create a device that can monitor internal wound healing and readily dissolve after healing.
Contact Information amy.liao@berkeley.edu, monica.lin@berkeley.edu
Advisor Michel M. Maharbiz

 
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Physical Sensors & Devices
Project IDBPN765
Project Title Full-Field Strain Sensor for Hernia Mesh Repairs
Status Continuing
Funding Source NSF
Keywords strain
Researchers Amy Liao
Abstract Each year, more than 400,000 ventral hernia repairs are performed in the United States. A hernia is the protrusion of an organ through a weak spot in the surrounding muscle or connective tissue that normal contains it. Large ventral hernias (hernias that occur in the abdominal wall) are typically treated by suturing in a surgical mesh to cover and overlap the hernia defect. The surgical mesh provides additional support to the damaged tissue surrounding the hernia. However, in 25-40% of patients, the hernia repair fails, resulting in recurrence of the hernia, along with other complications including infection and intestinal obstruction. We hypothesize that a major cause of hernia recurrence is the unequal distribution of stress across the mesh resulting in high stress concentrations at the tissue-mesh interface, particularly at the site of mesh fixation to the abdominal wall muscles. Over time the mesh is pulled away from the abdominal wall at the high stress concentrations and the hernia defect recurs. We propose to design a biocompatible, instrumented patch, capable of mapping the 2D strain topography placed on the mesh. The sensor will enable surgeons to actively identify and address areas of high stress during the surgery by modifying the surgical procedure to redistribute stress more evenly, thus decreasing the rate of hernia recurrence. Furthermore, our long term goal is to design a hernia mesh that contains strain gauges and the associated circuitry such that once implanted in the body the prosthetic can alert patients when they are engaging in activities that place high stress on the implant. Such a dynamic, interactive hernia mesh would empower patients to actively participate in their post- operative care in a way that is personalized and unprecedented in surgery.
Contact Information amy.liao@berkeley.edu
Advisor Michel M. Maharbiz

 
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BioMEMS
Project IDBPN769
Project Title Acousto-Optic Modulation of Brain Activity: Novel Techniques for Optogenetic Stimulation and Imaging
Status New
Funding Source Tri-Institutional Brain R&D Initiative
Keywords Acousto-optics, Nonlinear nanocrystals, Brain, Central nervous system
Researchers Maysam Chamanzar
Abstract One of the fundamental challenges in monitoring and modulating central nervous system activity is the lack of tools for non- invasive interrogation of local neuronal ensembles simultaneously in different regions of the brain. Despite recent advances in neural modulation techniques, including a rapidly expanding optogenetic and imaging toolset, still we lack a robust, minimally- invasive optogenetic stimulation platform. The ability to independently deliver light to multiple, highly- localized regions of the brain would drastically improve in vivo optogenetic experiments. Illuminating a large volume of brain using light sources above the brain surface does not provide the requisite spatial resolution, and since the intensity diminishes rapidly, only a small fraction of target neurons in the vicinity of the light source (~200 µm) will be excited. Increasing the light source power, on the other hand, results in the generation of excessive heat in the brain and the potential for tissue damage. In this project, we use specially designed up converting nanocrystal particles (UCNP) to deliver light locally to neurons. We use an acoustic-optics modality to deliver and steer light in the brain from outside without causing damage to the brain tissue.
Contact Information chamanzar@berkeley.edu
Advisor Michel M. Maharbiz

 
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BioMEMS
Project IDBPN699
Project Title A Modular System for High-Density, Multi-Scale Electrophysiology
Status Continuing
Funding Source NSF
Keywords Neuroengineering, Nanoprobes, Optogenetics, ASIC, BioMEMS
Researchers Maysamreza Chamanzar
Abstract Truly large-scale electrophysiology simultaneous recording of thousands of individual neurons in multiple brain areas remains an elusive goal of neuroscience. The traditional approach of studying single neurons in isolation assumes that the brain can be understood one component at a time. However, in order to fully understand the function of whole brain circuits, it is essential to observe the interactions of large numbers of neurons in multiple brain areas simultaneously with high spatiotemporal resolution. This project will establish a complete system for multi-scale electrophysiology in awake, freely behaving mice, using state-of-the-art nano neural interfaces comprising of tiny silicon probes integrated with on- chip optical waveguides and compliant monolithic polymer cables connected to a unique light-weight head-mounted recording system built around a commercially available application specific integrated circuit (ASIC) that has been custom designed for electrophysiological recordings, combining signal amplification, filtering, signal multiplexing, and digital sampling on a single chip. We demonstrate the high-resolution excitation of channelrhodopsin-expressing neurons imaged on a two-photon microscope by evoking action potentials in different parts of cortex. The entire process, including post-fabrication system integration, has been designed to leverage existing consumer manufacturing processes, making our probe technology mass- producible and widely accessible at low cost.
Contact Information chamanzar@berkeley.edu
Advisor Michel M. Maharbiz, Timothy J. Blanche

 
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BioMEMS
Project IDBPN745
Project Title Wafer-Scale Intracellular Carbon Nanotube-Based Neural Probes
Status Continuing
Funding Source Fellowship
Keywords
Researchers Konlin Shen
Abstract Current in-vivo methods of electrical recordings of the brain are hampered by low spatial resolution, invasiveness to the surrounding tissue, and scalability. Carbon nanotube based electrodes are ideal for intracellular neural recordings due to their small size and flexibility, allowing for higher density arrays and less damage to the brain. However, current methods for selective placement and alignment of carbon nanotubes cannot be done easily on a wafer scale. This project aims to solve this issue in order to create wafer-scale carbon nanotube based neural probes for intracellular recordings.
Contact Information konlin@berkeley.edu, maharbiz@eecs.berkeley.edu
Advisor Michel M. Maharbiz

 
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BioMEMS
Project IDBPN716
Project Title Neural Dust: An Ultrasonic, Low Power Solution for Chronic BrainMachine Interfaces
Status Continuing
Funding Source Fellowship
Keywords brain-machine interfaces, ultrasonic energy transfer and harvesting, backscatter communication
Researchers Dongjin Seo
Abstract A major hurdle in brain-machine interfaces (BMI) is the lack of an implantable neural interface system that remains viable for a substantial fraction of a primate lifetime. Recently, sub-mm implantable, wireless electromagnetic (EM) neural interfaces have been demonstrated in an effort to extend system longevity. However, EM systems do not scale down in size well due to the severe inefficiency of coupling radio waves at mm and sub-mm scales. We propose an alternative wireless power and data telemetry scheme using distributed, ultrasonic backscattering systems to record high frequency (~kHz) neural activity. Such systems will require two fundamental technology innovations: 1) thousands of 10 – 100 um scale, free-floating, independent sensor nodes, or neural dust, that detect and report local extracellular electrophysiological data via ultrasonic backscattering, and 2) a sub-cranial ultrasonic interrogator that establishes power and communication links with the neural dust. To test the feasibility of this approach, we performed the first in-vivo experiments in the rat model, where we were able to recover mV-level action potential signals from the peripheral nerves. Further miniaturization of implantable interface based on ultrasound would pave the way for both truly chronic BMI and massive scaling in the number of neural recordings from the nervous system.
Contact Information djseo@eecs.berkeley.edu
Advisor Michel M. Maharbiz

 
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BioMEMS
Project IDBPN718
Project Title Direct Electron-Mediated Control of Hybrid Multi-Cellular Robots
Status Continuing
Funding Source Office of Naval Research (ONR)
Keywords microbiorobotics, synthetic biology, biosensors, stochastic control, hybrid biological systems, bacterial electrophysiology
Researchers Tom J. Zajdel
Abstract We propose to design, fabricate and test a millimeter-scale, programmable cellular- synthetic hybrid robot capable of autonomous motility, sensing and response in aqueous environments. Three integrated technologies will make this possible: 1) two-way electron transfer between an electrode and E. coli for rapid communication between abiotic core and cells; 2) a flexible polymer + CMOS sensing and computation abiotic core; 3) synthetic cell adhesion genes which allow for patternable self-assembly of bacterial cells onto the abiotic substrate. If successful, this will be the first demonstration of a millimeter-scale synthetic autonomous multi-cellular hybrid with organic and man-made components. A primary goal of this work will be to enable abiotic/biotic two- way communication via electron transfer channels engineered into cells in contact with microelectrodes. We suggest that such a fusion would enable control techniques that rely on combinations of gene expression, cell-level sensing / actuation and CMOS digital computation.
Contact Information zajdel@eecs.berkeley.edu, maharbiz@berkeley.edu
Advisor Michel M. Maharbiz

 
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BioMEMS
Project IDBPN795 New Project
Project Title An Implantable Micro-Sensor for Cancer Surveillance
Status New
Funding Source NSF
Keywords
Researchers Stefanie V. Garcia, Leticia Ibarra
Abstract We aim to develop a micro surveillance device for early identification of cancerous cell growth in collaboration with radiation oncology research from UCSF. UCSF will develop a molecular probe that specifically targets prostate specific membrane antigen (PSMA), which is over-expressed on prostate cancer cells. By radiolabelling these probes, cancer sites may be monitored in conjunction with an implantable array. We will design a 100x100 um semiconductor radiation sensor that can feasibly detect and localize cancer recurrence from 10^4 – 10^5 cells when placed near a cancer site. The sensors will use ultrasonic methods for power and signal transmission, as demonstrated in Dongjin et al, arXiv preprint arXiV:1307.2196 (2013). Initial sensor design will enhance CMOS device sensitivity to time dependent signal variation and will also explore signal recovery in the limited biological window where the radiolabelled probe is detectable.
Contact Information stefanievgarcia@berkeley.edu, ibarra.leticia@berkeley.edu
Advisor Michel M. Maharbiz, Kristofer S.J. Pister

 
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Physical Sensors & Devices
Project IDBPN731
Project Title Flexible Electrodes and Insertion Machine for Stable, Minimally-Invasive Neural Recording
Status Continuing
Funding Source DARPA
Keywords neural recording, scalable, flexible, surgical robot, minimally invasive
Researchers Timothy L. Hanson
Abstract Current approaches to interfacing with the nervous system mainly rely on stiff electrode materials, which work remarkably well, but suffer degradation from chronic immune response due to mechanical impedance mismatch and blood-brain barrier disruption. This current technology also poses limits on recording depth, spacing, and location. In this project we aim to ameliorate these issues by developing a system of very fine and flexible electrodes for recording from nervous tissue, a robotic system for manipulating and implanting these electrodes, and a means for integrating electrodes with neural processing chips. We have fabricated five versions of the electrodes, and have demonstrated their manual and automated insertion into an agarose tissue proxy and ex-vivo brain using a etched tungsten needle. We have also fabricated and tested in agarose three revisions of the inserter robot. The most recent inserter robot design uses a replaceable electrode cartridge to which electrodes are mounted; these electrodes are made on a 5um thick polyimide substrate with a parylene peel-away backing. The parylene backing holds the fine wires and keeps them from tangling until they are inserted, and provides a more robust means of handling and mounting the structures. Simultaneously, we have been developing a machine for laser and resistance micro-welding the insertion needle, and have completed several promising test needles. We hope to test the full system in rats within a month.
Contact Information tlh24@phy.ucsf.edu
Advisor Michel M. Maharbiz, Philip N. Sabes

 
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BioMEMS
Project IDBPN573
Project Title Carbon Fiber Microelectrode Arrays for Chronic Stimulation and Recording in Insects
Status Continuing
Funding Source State
Keywords carbon fiber microelectrode electrode array insect electrophysiology chronic stimulation recording fly beetle
Researchers Travis L. Massey
Abstract This project aims to create an array of carbon fibers for insect electrophysiology.
Contact Information tlmassey@eecs.berkeley.edu
Advisor Michel M. Maharbiz, Kristofer S.J. Pister

 
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BioMEMS
Project IDBPN571
Project Title Implantable Microengineered Neural Interfaces for Studying and Controlling Insects
Status Continuing
Funding Source Industry
Keywords insect, vision, neural interface, micro aerial vehicle
Researchers Joshua van Kleef, Kaylee Mann
Abstract Our goal is to control the flight of an insect by hijacking its sensory systems. Although significant funding has gone into developing micro air vehicles (MAVs, wingspan< 15cm), flying insects still significantly outperform the most sophisticated flying robots in efficiency, flight time, stability and maneuverability. The restrictions that such a small spatial scale places on the amount of energy that can be stored on-board and on actuator efficiency, means this gap is expected to continue for some years to come. We are therefore pursuing a novel MAV design that uses an actual flying insect. We aim to produce small insect backpacks capable of receiving commands remotely and providing power to a combination of neural and optical stimulators. The patterns of stimulation will allow us to trick the insects motor-sensory system into responding to fictitious self-movements. We aim to use these ‘ghost’ stimuli to remote-control the insect’s flight while at the same time capitalizing on their remarkable natural flying abilities. The project has now advanced to testing devices in free flight and optimizing the stimulation parameters.
Contact Information vankleef@berkeley.edu, maharbiz@eecs.berkeley.edu
Advisor Michel M. Maharbiz

 
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BioMEMS
Project IDBPN771
Project Title Silicon Carbide ECoGs for Chronic Implants in Brain-Machine Interfaces
Status Continuing
Funding Source BSAC Member Fees
Keywords
Researchers Camilo A. Diaz-Botia, Lunet E. Luna
Abstract Electrocorticography (ECoG) is an excellent brain mapping technique that places large arrays of electrodes directly on the cortex of the brain, and has been used in patients for several decades. Utilization of this technique results in an improved trade-off between spatial and temporal resolution. In recent years, the development of high-density, polymer-based micro- ECoGs has pushed the field even further, allowing even better neural circuit observation in acute recordings. Despite these advances, an unsolved challenge remains in terms of device longevity. Polymer-based micro-ECoGs are not suitable for chronic implantation within brain tissue, the interfacial layers within the device allow molecule penetration causing delamination, which overtime leads to device failure. However, silicon carbide (SiC)-based micro ECoGs are expected to enhance device structural and chemical stability, and thus lengthen the device lifetime compared to polymer-based micro- ECoGs. SiC is a biocompatible that can provide micro-ECoGs with the mechanical and chemical stability they are currently lacking within the reactive or harsh-environment of the body. Our goal is to design SiC- based micro-ECoG arrays that can serve as effective, robust chronic implants.
Contact Information cadiazb@berkeley.edu, lunet@berkeley.edu
Advisor Michel M. Maharbiz, Roya Maboudian

 
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BioMEMS
Project IDBPN756
Project Title MEMS Devices for Oral Delivery of Proteins and Peptides
Status Continuing
Funding Source Federal
Keywords MEMS, Oral Drug Delivery
Researchers Kiana Aran, Marc Chooljian
Abstract Oral delivery of proteins and large molecule drugs has been a challenge due to the denaturing effects of digestive environment, enzymatic destruction and poor GI mucus permeability, leading to extremely low drug bioavailability and therapeutic efficacy. In spite of considerable efforts over the past decades, oral delivery of proteins and large molecule drugs with low therapeutic efficacy and bioavailability remains a major challenge. There is a great need for a suitable oral delivery system which can maintain the protein integrity, improve bioavailability and overcome the mucus barrier for maximum absorption. MucuJet is a high pressure jet-injector oral pill, for oral to systemic delivery of drugs. MucuJet can protect drugs from digestive destruction and can eject drugs with high pressure in the lumen of small intestine which can penetrate intestinal mucus, thereby overcoming the limitation associated with low diffusion rate across mucosal barrier. The feasibility of using MucuJet for enhancing intestinal absorption was tested in vitro which indicated that MucuJet is capable of high velocity drug release and is able to increase protein absorption in short amount of time with no significant effect on cell viability.
Contact Information k.aran@berkeley.edu
Advisor Dorian Liepmann, Niren Murthy

 
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BioMEMS
Project IDBPN757
Project Title Biosensors Based on Biologically Responsive Polymers
Status Continuing
Funding Source Federal
Keywords Reactive oxygen species
Researchers Kiana Aran
Abstract This project presents the design, fabrication and testing of novel plastic-based lab-on a chip (LOC) biosensors which utilize stimuli responsive polymers as their recognition element. The biosensors are composed of interdigitated electrodes (IDE) coated with a thin film of a responsive polymer. In the presence of stimuli, the responsive polymer degrades from the surface of the IDE, and generates a measurable electrical signal that correlates with the amount of stimuli present in the sample. This technology can be utilized as an accurate, label-free, cost-effective method for engineering biosensors for clinical applications.
Contact Information k.aran@berkeley.edu
Advisor Dorian Liepmann, Niren Murthy

 
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BioMEMS
Project IDBPN729
Project Title Development of Microfluidic Devices with Embedded Microelectrodes using Electrodeposition and Hot Embossing
Status Continuing
Funding Source BSAC Member Fees
Keywords
Researchers Marc Chooljian, Kathryn Fink
Abstract The use of microfluidic devices has experienced a tremendous increase over the last years, especially valuable for healthcare applications. In this context plastic materials are increasingly relevant especially for large scale fabrication and commercialization. However plastics are still not widely used at the research level due to the lack of available inexpensive industrial–like fabrication equipment. In this work we describe a rapid and highly cost-effective approach for fabricating plastic microfluidic devices with embedded microelectrodes allowing 2D and 3D configurations. We present an interdigitated microelectrode configuration applied to impedance cytometry and cellular electroporation/lysis on chip devices as an example of the great potential of this technology. Our long-term goals are to further explore the potential of hot-embossed microscale devices as platforms for complete BioMEMS devices. This includes the integration of functionalized elements and silicon-based biosensors.
Contact Information mschooljian@berkeley.edu
Advisor Dorian Liepmann

 
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Microfluidics
Project IDBPN711
Project Title Point-of-Care System for Quantitative Measurements of Blood Analytes Using Graphene-Based Sensors
Status Continuing
Funding Source NSF
Keywords Biosensor, healthcare, graphene, microfluidics
Researchers Kiana Aran, Kathryn Fink
Abstract Serum glucose, cholesterol, triglyceride and HbA1C monitoring are all valuable tools in the health management of the aging population, especially given the increase in diabetes and cardiovascular diseases. Even for glucose monitoring, the challenges obtaining sufficiently accurate and reliable measurements are so significant that the FDA is contemplating more stringent standards. Guido Freckmann, et al., J. Diabetes Sci. Tech. 6, 1060-1075, 2012, have compared 43 blood glucose self-monitoring systems. Out of this, 34 systems were completely assessed and 27 (79.4%) systems fulfilled the minimal accuracy requirements and only 18 (52.9%) of 34 systems fulfilled the requirements of the proposed tighter criteria in the current standards draft. None of them meet the even more stringent requirement of ISO 2012 and FDA. Because inaccurate systems bear the risk of false therapeutic decisions and rising health care costs, there is an urgent need for significantly enhanced BG monitoring systems for PC applications. POC tests for other biomedically important analytes are generally even less accurate. The overall goal of the proposed research is to develop new sensor platforms that will provide increased sensitivity and accuracy in point-of-care situations. This is a joint project with Harvard Medical School and Vanderbilt University.
Contact Information liepmann@berkeley.edu; jparedes@berkeley.edu
Advisor Dorian Liepmann

 
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Microfluidics
Project IDBPN732
Project Title The Role of Erythrocyte Size and Shape in Microchannel Fluid Dynamics
Status Continuing
Funding Source NSF
Keywords
Researchers Kathryn Fink, Karthik Prasad
Abstract The unique properties of blood flow in microchannels have been studied for nearly a century; much of the observed blood-specific dynamics is attributed to the biconcave shape of red blood cells. However, for almost twice as long biologists have observed and characterized the differences in the size and shape of red blood cells among vertebrates. With a few exceptions, mammals share the denucleated biconcave shape of erythrocytes but vary in size; oviparous vertebrates have nucleated ovoid red blood cells with size variations of a full order of magnitude. We utilize micro-PIV and pressure drop measurements to analyze blood flow of vertebrate species in microchannels, with a focus on understanding how cell size and shape alter the cell-free layer and velocity profile of whole blood. The results offer insight into the Fahraeus-Lindqvist effect and the selection of animal blood for the design and evaluation of biological microfluidic devices.
Contact Information kdfink@berkeley.edu, liepmann@berkeley.edu
Advisor Dorian Liepmann

 
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Physical Sensors & Devices
Project IDBPN770
Project Title Chemical Sensitive Field Effect Transistor (CS-FET)
Status Continuing
Funding Source NSF
Keywords CS-FET, Gas Sensor, microfabrication, TMO
Researchers Hossain M. Fahad, Hiroshi Shiraki
Abstract Silicon IC-based fabrication processing will be used to develop novel compact gas sensors that, unlike current sensors, will operate at room temperature, consume minimal power, exhibit superior sensitivity, provide chemical selectivity and multi-gas detection capabilities, and offer the prospect of very low-cost replication for broad-area deployment. We name this device structure “Chemical Sensitive FET” or “CS-FET.” The operation of the CS-FET involves transistor parametric differentiation under influence of differentiated gas exposures.
Contact Information hossain.fahad@berkeley.edu, shiraki@berkeley.edu
Advisor Ali Javey

 
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NanoTechnology: Materials, Processes & Devices
Project IDBPN704
Project Title Vapor-Liquid-Solid Growth of Polycrystalline Indium Phosphide Thin Films on Metal
Status Continuing
Funding Source Federal
Keywords Solar Cells, Photovoltaics, Indium Phosphide, InP, VLS, Thin Film
Researchers Maxwell Zheng, Mark Hettick, Joy Wang, Weitse Hsu, Peter Lobaccaro
Abstract Here, we develop a technique that enables direct growth of III-V materials on non- epitaxial substrates. Here, by utilizing a planar liquid phase template, we extend the VLS growth mode to enable polycrystalline indium phosphide (InP) thin film growth on Mo foils.
Contact Information mszheng@eecs.berkeley.edu
Advisor Ali Javey

 
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NanoTechnology: Materials, Processes & Devices
Project IDBPN792 New Project
Project Title Thin Film InP Photoelectrochemical Cells for Efficient, Low-Cost Solar Fuel Production
Status New
Funding Source Federal
Keywords
Researchers Mark Hettick, Maxwell Zheng
Abstract While bulk p-type InP wafers have produced high efficiency photoelectrochemical water-splitting cells, the high cost of epitaxial substrates limits viability at a larger scale. Here, we utilize low-cost growth of InP on non-epitaxial substrates with the thin-film vapor-liquid-solid method to provide high efficiency, scalable photocathode cells for the hydrogen evolution reaction.
Contact Information mark.hettick@berkeley.edu, mszheng@eecs.berkeley.edu, ajavey@eecs.berkeley.edu
Advisor Ali Javey

 
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NanoTechnology: Materials, Processes & Devices
Project IDBPN777 New Project
Project Title Nonepitaxial Growth of Single Crystalline III-V Semiconductors onto Insulating Substrates
Status New
Funding Source Federal
Keywords
Researchers Kevin Chen
Abstract III-V semiconducting materials have many characteristics such as high electron mobilities and direct band gaps that make them desirable for many electronic applications including high performance transistors and solar cells. However, these materials generally have a high cost of production which significantly limits their use in many commercial applications. We aim to explore new growth methods which can grow high quality crystalline III-V films, using InP as an example substrate, onto non-epitaxial substrates. In addition to excellent crystal quality, critical considerations include cost and scalability for commercially viable applications.
Contact Information kqchen@eecs.berkeley.edu
Advisor Ali Javey

 
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Physical Sensors & Devices
Project IDBPN747
Project Title Electronic Skin: Fully Printed Electronic Sensor Networks
Status Continuing
Funding Source NSF
Keywords Flexible, printed electronics, thin film transistor
Researchers Kevin Chen
Abstract Large area networks of sensors which are flexible and can be laminated conformally on nonplanar surfaces can enable many different applications in areas such as prosthetics, display technology, and remote stimuli monitoring. For large area applications, printed electronics are favorable over traditional photolithography and shadow mask technology from a cost and throughput point of view and we demonstrate proof-of-concept for such a printed “electronic skin” system by printing a carbon nanotube based thin film transistor (TFT) active matrix backplane using a reverse roll to plate gravure printing design. This design allows for yields of up to 97% with printing conducted in an ambient environment and mobilities of up to 9 cm2/V⋅s, the highest reported for a fully printed TFT. Pressure sensors are then integrated onto the active matrix backplane, which enables mapping of the pressure profile across the active matrix area. In the future, this could be integrated with other types of sensors and devices to enable more functionality.
Contact Information kqchen@eecs.berkeley.edu
Advisor Ali Javey

 
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NanoTechnology: Materials, Processes & Devices
Project IDBPN776
Project Title Wearable Electronic Tape
Status Continuing
Funding Source NSF
Keywords
Researchers Hiroki Ota, Kevin Chen
Abstract We demonstrate a high-performance wearable piezoelectric electronic-tape (E-tape) for motion sensing based on a carbon nanotube (CNT)/silver nanoparticle (AgNP) composite encased in PDMS and VHB flexible thin films. E-tape sensors directly attached to human skin exhibit fast and accurate electric response to bending and stretching movements which induce change in conductivity with high sensitivity. Furthermore, E-tape sensors for a wide range of applications can be realized by the combination of controlling the concentration of AgNPs in the CNT network and designing appropriate device architectures. The reliability and scalability of E- tape sensors combined with compatibility with conventional micro-fabrication open up new routes for integration of nanoelectronics into flexible human interfaces at the system level.
Contact Information hiroki.ota@berkeley.edu, kqchen37@gmail.com
Advisor Ali Javey

 
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Physical Sensors & Devices
Project IDBPN746
Project Title Liquid Heterojunction Sensors
Status Continuing
Funding Source NSF
Keywords Microfluidics, flexible, sensor, hetero-junction
Researchers Hiroki Ota, Kevin Chen
Abstract In recent years, mechanically deformable devices and sensors have been widely explored for various applications such as paper-thin displays and electronic skin for prosthetics and robotics. Liquids are extremely deformable and have shown promise for these applications, with previous works demonstrating pressure sensors with the ability to be stretched by up to 250% before failure. However, current technology is limited to a single liquid material as liquids tend to intermix when placed together, limiting the range of sensors that can be achieved. Here, in this work, we show a new concept for a liquid-liquid “hetero-junction” temperature sensor with liquid InGaSn metal as a passive interconnect and an imidazolium based ionic liquid as the active sensing element. By proper choice of liquids and design of the liquid-liquid interface, we are able to prevent the liquids from mixing, leading to exciting prospects for more complex liquid based flexible electronics.
Contact Information hiroki.ota@berkeley.edu, kqchen@eecs.berkeley.edu
Advisor Ali Javey

 
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NanoTechnology: Materials, Processes & Devices
Project IDBPN694
Project Title Monolayer Semiconductor Devices
Status Continuing
Funding Source Federal
Keywords Monolayer; Layered chalcogenide; Electronics
Researchers Mahmut Tosun, Tania Roy, Daisuke Kiriya
Abstract Two-dimensional layered semiconductors present a promising material platform for band-to-band- tunneling devices given their homogeneous band edge steepness due to their atomically flat thickness. Here, we experimentally demonstrate interlayer band-to-band tunneling in vertical MoS2/WSe2 van der Waals (vdW) heterostructures using a dual-gate device architecture. The electric potential and carrier concentration of MoS2 and WSe2 layers are independently controlled by the two symmetric gates. The same device can be gate modulated to behave as either an Esaki diode with negative differential resistance, a backward diode with large reverse bias tunneling current, or a forward rectifying diode with low reverse bias current. Notably, a high gate coupling efficiency of ~ 80% is obtained for tuning the interlayer band alignments, arising from weak electrostatic screening by the atomically thin layers. This work presents an advance in fundamental understanding of the interlayer coupling and electron tunneling in semiconductor vdW heterostructures with important implications toward the design of atomically thin tunnel transistors.
Contact Information mtosun@lbl.gov, tania.roy@berkeley.edu, kiriya@berkeley.edu
Advisor Ali Javey