Research Project Descriptions
A complete copy of the project descriptions (Including: Approach and Methodology, Results and Accomplishments and Milestone Dates) are available to Center Members in the Members Only section of our website at www.wimserc.org
Contents:
Micropower Circuits Micropackaging, Microfabrication, and Power Source Technologies Environmental Sensors & Subsystems Biomedical Sensors & Subsystems Wireless Interfaces
Micropower Circuits
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Title:  Improved Process Variation Detection and Compensation for Gen-3 WIMS Microcontroller
Graduate Students: Amlan Ghosh (ECE-UT) Funding Source: WIMS ERC	Faculty Advisor: Richard B Brown (ECE-UT) Work Began: 09/20/2007
Project Goals:
The need for accurate detection schemes to facilitate the mitigation of process variations has increased in the nm technology era. A new detection technique will be incorporated in the Gen-3 WIMS microcontroller that uses slew, as well as delay, to determine n- and p-type transistor parameters. The transistor thresholds can be adjusted using the process variation data to drive the substrate bias. When circuits are compensated for process variation in this way, they will operate optimally with the minimum supply voltage for a given frequency, thereby reducing power dissipation.
Title:  Integrating Software and Hardware Components for the Cochlear Implant and Micro Gas Chromatograph
Graduate Students: Daniel E. Mera (ECE-UPRM) Undergraduate Students: Wilfredo O. Cartagena-Rivera, Leonardo A. Ortiz, Armando Vega , Jaime A. Torres Funding Source: WIMS ERC	Faculty Advisor: Nayda G. Santiago (ECE-UPRM) Work Began: 08/01/2008
Project Goals:
The main goal of our project is to integrate the various components of software and hardware for both WIMS testbeds. In particular for the Neural Prosthesis Testbed (NPT), we are working with the Cochlear Implant System and for the Environmental Monitoring Testbed (EMT) with the micro gas chromatograph. For the µGC project, we want to integrate the functionality of the wireless communication from host PC to the µGC using 8 data communication canals and for the Cochlear Implant Testbed to control multi-site and multipolar current stimulation using DAQ PCI6723 TI card. This integration involves to apply low power optimizations to make the prototype energy efficient.
Title:  Readout Circuitry for Wireless Sensing of Intraocular Pressure
Graduate Students: Shubha Kyatsandra (EE-PVAMU), Crystal G. Robinson (EE-PVAMU) Funding Source: WIMS ERC	Faculty Advisor: Pamela Holland Obiomon (EE-PVAMU) Work Began: 09/01/2004
Project Goals:
The goal of this project is to demonstrate a very-low-power microsystem which gathers pressure data from the anterior chamber in the eye for glaucoma detection and prevention. The overall system is illustrated in Figure 1. The microsystem provides the functions of sensing, data readout, and local storage. The blocks needed for each function are shown in Figure 2. This research will focus mainly on the data readout function.
Title:  Design and Implementation of a Wireless Implantable System for a Neural Prosthesis
Graduate Students: Spencer S. Kellis (ECE-UT), Nathaniel C. Gaskin (ECE-UT) Funding Source: WIMS ERC	Faculty Advisor: Richard B Brown (ECE-UT) Work Began: 09/01/2005
Project Goals:
A third-generation wireless, implantable system which evolved from the WIMS Gen-2 microcontroller is being designed as a control element for a neural prosthesis to operate on a limited-power budget. Among the principal additions to the Gen-3 system will be a fully custom signal processor perform on-chip analysis of surface potentials recorded from nonpenetrating microwire arrays. Improvements to the underlying system include a block load/store (referred to as DMA) instruction to reduce overhead in transferring large blocks of data between system components. Dynamic voltage, frequency scaling, and body biasing are considered as methods for significantly reducing power. We also experiment with other core architectural modifications which can improve handling of data flow from an analog processing block. With the addition of an on-chip wireless interface for low-power, high-bandwidth communication, the WIMS Gen-3 can operate efficiently both in the context of a biomedical implant for neural prosthesis control, as well as in a wide range of testing and sensor network applications. The Gen-3 pipeline and test circuits for the major components of the final design have been fabricated in IBM 65nm technology.
Title:  Design and Implementation of Low-Power DMA Architecture for a Cochlear Implant System-on-a-Chip
Graduate Students: Nathaniel C. Gaskin (ECE-UT), Spencer S. Kellis (ECE-UT), Amlan Ghosh (ECE-UT) Funding Source: WIMS ERC	Faculty Advisor: Richard B Brown (ECE-UT) Work Began: 09/01/2005
Project Goals:
Our primary objective is to implement direct memory access (DMA) in the WIMS microcontroller to enhance data transfer between memory and the loop cache. Dedicated DMA instructions are needed to fill the loop cache quickly without incurring the overhead of multiple load-store instructions. These instructions will allow a compiler-managed dynamic loop-cache filling algorithm to control fast, low-power transfer of an entire register window upon branches to or from subroutines and interrupt handlers. Overall power requirements can thereby be reduced, further enhancing the performance and longevity of the microcontroller. In addition to DMA, a low-power standard cell library will be designed and synthesized for several power-hungry blocks of the microcontroller in order to further decrease power requirements during heavy computation in the DSP core. Clock gating will be used to reduce the leakage current during no-operation of a block (power save mode).
Title:  Energy Scavenging From Low Frequency Vibrations
Graduate Students: Tzeno V. Galchev (EECS) Funding Source: NIST Post Doc: Hanseup S. Kim (EECS)	Faculty Advisor: Khalil Najafi (EECS) Work Began: 10/01/2006
Project Goals:
Self-powered remote microsystems and sensor networks are needed in many emerging applications such as environmental monitoring. The required power for these systems can be generated mainly in two ways: 1) by using electrochemical batteries and micro fuel cells and 2) by energy scavenging from environmental sources such as ambient heat, light, and vibration. Although electrochemical batteries and microfuel cells can provide more power, they are not desirable for some applications due to their limited lifetime, and size. A battery large enough to last the lifetime of the sensor would dominate the overall system size, and hence is not very attractive. As the sensor network increases in number and the device size decreases, the replacement of depleted batteries and fuel cells is not practical. Energy scavenging has become popular recently, because of the need for clean power generation process and long lifetime. By scavenging energy, power can be generated from various environmental sources such as ambient heat, light, acoustic noise, vibration, and ambient RF signals. The goal of this project is to develop an efficient energy scavenger for converting ambient low-frequency vibrations into electrical power. Low-frequency vibrations present a couple of significant challenges to energy scavenging: 1) as the frequency drops so does the expected power density, and 2) most of the vibrations in the applications enumerated above typically vary in frequency. Figure 1 shows the conceptual view of a vibration micro power generator.
Title:  MEMS-Based Energy Harvesting for Low-Frequency Vibrations
Graduate Students: Edwar Romero (MEEM-MTU) Funding Source: WIMS ERC Other Investigators: Khalil Najafi (EECS)	Faculty Advisor: Robert O Warrington (ME-MTU) Work Began: 05/01/2006
Project Goals:
Power generation for remote-controlled microsystems has faced limitations due to its energy source. Batteries are not the best option for applications where chemical reactions are involved, or access to the device is severely limited. Thus, energy scavenging from environmental sources can be an alternative. Energy harvesting has become important recently, because of the almost infinite lifetime and the non-dependency on fuels for clean-energy generation. By scavenging energy from sources such as light and vibration, power can be generated. Power generation through light sources can yield a high output, although it is not always a practical choice. In some cases, energy generation from vibration becomes feasible because of the abundant oscillations of the surrounding environment. This vibration frequency is typically below 10Hz. For example, human movements peak at around 1Hz. Thus, harvesting these low-frequency vibrations can generate energy for environmental, wearable, or implantable systems. The focus of this project is on generating energy efficiently from low-frequency vibration. In particular, MEMS-scale energy generators will be explored. A demonstration model will be built and optimized to illustrate how energy can be generated using low-frequency vibrations. Energy scavenging from body motion poses a challenge to traditional resonant frequency generators due to the large displacements and broad frequency spectrum inherently associated with human movement. The non-resonant rotational generator design presented here is found to be well suited for these types of motions.
Title:  The Phoenix Processor: A 30pW Platform for Sensing Applications
Graduate Students: Mingoo Seok (EECS), Scott M. Hanson (EECS) Funding Source: WIMS ERC Other Investigators: David Blaauw (EECS)	Faculty Advisor: Dennis M Sylvester (EECS) Work Began: 08/01/2006
Project Goals:
To meet the growing demand for pervasive computing systems, we have designed an ultra-low-power integrated platform for sensor applications, called the Phoenix Processor. Recent work has explored aggressive Vdd scaling for reducing active energy. However, the power consumed during idle periods, which can be >99% of the lifetime, dominates total power consumption. To limit sleep-mode power, Phoenix leverages a comprehensive sleep strategy using a unique power-gating approach, a CPU with compact instruction set; a custom, low-leakage, memory cell; adaptive leakage management in the data memory; and data-memory compression.
Title:  60GHz Front-End Circuit in CMOS With On-Chip Antenna for Wireless Sensor Network (WSN) Applications
Graduate Students: Kuo-Ken Huang (EECS) Funding Source: EECS Fellowship	Faculty Advisor: David D. Wentzloff (EECS) Work Began: 09/01/2008
Project Goals:
Wireless sensor nodes in a sensor network are typically equipped with radio transceiver, microcontroller, and energy source such as battery. The radio front-end dominates the sensor node’s size, robust communication distance between nodes and gateway, and lifetime under limited power supply. This project seeks to develop a fully integrated RF front-end circuit for Wireless Sensor Network (WSN) applications. On-chip antennas as well as front-end circuits will be integrated onto the integrated platform with other components such as microprocessor, sensors and batteries to realize a complete wireless sensor node. It aims to communicate with other nodes in a distance of 1000× its size length under ultra-low-power consumption.
Title:  A Micro Thermoelectric Generator for Microsystems
Graduate Students: Niloufar Ghafouri (EECS) Funding Source: DARPA Post Doc: Hanseup S. Kim (EECS)	Faculty Advisor: Khalil Najafi (EECS) Work Began: 06/01/2007
Project Goals:
The rapid growth in implantable electronic systems has increased the demand for on-site, small volume, and replacement-free energy sources as opposed to conventional batteries. On-site energy scavenging from various environmental sources including ambient heat, solar energy, and vibrations has been introduced as an efficient and promising approach. Thermoelectric generators have advantages in reliability, absence of moving parts, and silent operation. Therefore, despite their high cost and low efficiency, there has been an increased interest in waste heat energy conversion by the fabrication of micro thermoelectric generators (micro-TEG). Power provision is one of the challenging requirements for microsystems on hybrid beetles. This work focuses on the use of body heat generated by beetles as an energy source. The goal of this project is to develop a micro-TEG with the area of approximately 1cm2 that is capable of generating 20–50µW/cm2/°C.
Title:  Mechanical Energy Scavenging From Flying Insects
Graduate Students: Ethem Erkan Aktakka (EECS) Funding Source: DARPA Post Doc: Hanseup S. Kim (EECS)	Faculty Advisor: Khalil Najafi (EECS) Work Began: 06/01/2007
Project Goals:
As ultra-low-power circuits and microsystems develop, conventional batteries used for these systems could be replaced with smaller-sized and longer-lifetime candidates. In this sense, energy harvesters hold great advantages such as unlimited lifetime, and no need for recharging or power cables. Mechanical energy harvesters are especially useful for environments that are exposed to external vibration and forces, like the wing of an insect. The goal of this research is to develop an efficient microscale power generator that harvests energy of >50µW within a volume of <0.01cc and a weight of <0.2g from live beetles as a part of the DARPA HI-MEMS (Hybrid Insect) Project. This small-energy scavenger could be used in a number of other WIMS applications.
Title:  Clock Harvesting for Wireless Sensor Networks
Graduate Students: Jonathan K. Brown (EECS) Funding Source: WIMS ERC	Faculty Advisor: David D. Wentzloff (EECS) Work Began: 09/01/2008
Project Goals:
Wireless sensor networks for environmental, medical, and industrial applications require long-term deployments and small unit volumes to make them both cost effective and unobtrusive. The simultaneous need for long lifetime, small volume, and portability, however, puts significant strain on the typical energy source for such a system—a battery. To reduce the burden on the battery, each node must utilize energy efficient circuitry. Of the circuit elements, wireless radios typically consume large amounts of energy for data transmission, making continuous communication infeasible. With heavily duty-cycled communication though, accurate timekeeping becomes critical for synchronization between nodes. Therefore, this project seeks to develop a wake-up radio, which will run in an ultra-low-power state on each wireless sensor node and awaken the node when a synchronization beacon is transmitted remotely (Figure 1). This eliminates the need for accurate integrated timing elements on each node, reducing overall system energy consumption.
Micropackaging, Microfabrication, and Power Source Technologies
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Title:  A 100W RF Power Switch
Funding Source: Darpa	Work Began: 05/01/2009 Project Completed: //
Title:  Smart All-Diamond Packaging for WIMS
Graduate Students: Zongliang Cao (ECE-MSU) Funding Source: WIMS ERC	Faculty Advisor: Dean M Aslam (ECE-MSU) Work Began: 08/15/2006
Project Goals:
This project’s goals are to develop a smart all-diamond packaging technology where the material for the packaging, device, and the interconnects is poly-C (Figure 1) and to put an energy scavenging device inside the package. It opens up the possibility of powering MEMS devices from scavenged ambient power (Figure 2).
Title:  An Actively Controlled Microvalve for Cooling and Drug Delivery
Graduate Students: Allan T. Evans (EECS), Jong M. Park (EECS) Funding Source: NASA, U-M Dept. of Anesthesiology Other Investigators: Srinivas Chiravuri (ANES), Gregory Nellis (ME-UW-Madison), Sanford Klein (ME-UW-Madison), Pat Roach (NASA-Ames Research Center)	Faculty Advisor: Yogesh B Gianchandani (EECS) Work Began: 01/01/2005
Project Goals:
One goal of this project is to create a micromachined actively controlled valve that is capable of operating reliably at very low temperatures (≈20K), and provides large flow-area variation. Such a valve will be used on future NASA missions that require cooling with high-degree temperature stability and small-temperature gradients. Another goal of this project is to incorporate the valve technology into a low-power, drug-delivery device. Valve regulation offers size and power decreases over pump dosing of medication. This is particularly true for high-volume intrathecal drugs. Valve-based, drug-delivery systems with integrated sensors will allow patients a portable delivery solution that offers several improvements on current implantable technology.
Title:  Microdischarge-Based Pressure Sensor, Sputter-Ion Pump and Harsh Environment Chemical Sensor
Funding Source: Advanced Energy Consortium Post Doc: Scott A. Wright (EECS)	Faculty Advisor: Yogesh B Gianchandani (EECS) Work Began: 06/01/2005
Project Goals:
This project is developing microdischarge-based devices for pressure measurement, environmental control inside sealed packages, and the detection of chemicals in high-temperature environments. Encapsulated microdischarge-based pressure sensors are being developed for operation in oil reservoirs at elevated temperatures and pressures. Microdischarge-based devices are attractive as they can operate at these high temperatures, and pressure sensors for gaseous measurements at 1,000°C have been developed [1]. This project is also developing a high-vacuum, microscale-sputter-ion pump, which bonds gases inside a sealed cavity to metal to reduce the pressure [2]. Removing certain molecules also allows for purification of the packaged environment [3]. A harsh environment chemical sensing system for petroleum monitoring and detection has been developed.
Title:  Batch-Mode Ultrasonic Micromachining of Ceramics and Application to Sensors and Actuators
Funding Source: WIMS ERC Post Doc: Tao Li (EECS) Other Investigators: Roma Y. Gianchandani (UM-Internal Medicine)	Faculty Advisor: Yogesh B Gianchandani (EECS) Work Began: 06/01/2003
Project Goals:
This project develops the batch-mode ultrasonic micromachining process which achieves transfer of lithographic patterns onto hard, brittle, and non-conductive materials such as ceramics (including PZT) and glass. The process is then used to create a micromachined biopsy tool with integrated sensors to provide real-time guidance for the medical procedure of fine needle aspiration (FNA) biopsy.
Title:  Low-Power Thermal Isolation for Environment-Resistant Microinstruments
Funding Source: DARPA Post Doc: Sang Woo Lee (EECS), Sang-Hyun Lee (EECS)	Faculty Advisor: Khalil Najafi (EECS) Work Began: 01/01/2004
Project Goals:
The environment has a profound impact on the performance of precision micromachined instruments increasingly needed in many applications. To realize the potential of MEMS, it is critical that the environment, especially temperature, around the instrument be controlled. External temperature can easily corrupt the output of an instrument, and can induce long-term undesirable effects that are not easily correctable using electronics. An effective approach to overcome this temperature sensitivity is to control/maintain temperature using a micro-oven. In order to achieve low-power consumption for micro-oven control, a very-high-thermal isolation is needed. This project seeks to develop a new thermal isolation package, and a generic assembly approach for instrument-platform integration.
Title:  Fabrication of Multi-Functional Carbon Nanotube Structures for Environmental and Biomedical Microsystems
Graduate Students: Sameh H. Tawfick (ME), Sister Mary Elizabeth Merriam (EECS), Rebecca Veeneman (CHEM), Thitiporn Sukaew (EHS) Funding Source: WIMS ERC; NSF Nanomanufacturing Program Other Investigators: Katharine T. Beach (EECS), Robert J. Gordenker (EECS), Edward T. Zellers (EHS), Kensall D. Wise (EECS)	Faculty Advisor: Anastasios John Hart (ME) Work Began: 01/01/2009
Project Goals:
This project seeks to demonstrate integration of carbon nanotubes (CNTs) in the U-M WIMS testbeds, and to create CNT fabrication methods that can benefit the U-M MEMS and LNF user community in other ongoing and future efforts. Specifically, we aim to create and test CNT structures as patterned vapor preconcentrator adsorbents, as nanoscale columns for on-chip chromatography, and as low-impedance coatings on neural recording and stimulation electrodes.
Title:  Wafer-Level Fabrication of High Performance Piezoelectric MEMS
Graduate Students: Ethem Erkan Aktakka (EECS) Funding Source: DARPA Post Doc: Hanseup S. Kim (EECS)	Faculty Advisor: Khalil Najafi (EECS) Work Began: 08/01/2008
Project Goals:
Bulk piezoelectric ceramics, unlike deposited piezoelectric thin (µm) films, provide greater electromechanical force, structural strength, and charge capacity, which are highly desirable in many MEMS applications including high-force actuators, harsh-environmental sensors, and micropower scavengers. Previous studies for integration of bulk ceramics in MEMS have faced significant challenges such as non-patternable bond layer, low-bond strength due to high stress and voids in bond layer, or out-diffusion of lead and re-polarization issues due to high-temperature processing. The goal of this research is to develop a batch-mode fabrication technology for integration of bulk piezoelectric materials into MEMS devices via low-temperature, fluxless, patternable, and reliable solder bonding (conductive) and polymer bonding (non-conductive) of bulk PZT on Si wafers, both in die and wafer level.
Title:  Poly-C Micro- and Nanoresonators
Graduate Students: Zongliang Cao (ECE-MSU) Funding Source: WIMS ERC	Faculty Advisor: Dean M Aslam (ECE-MSU) Work Began: 01/01/2006
Project Goals:
The goals of this project are to (a) design, fabricate, and test poly-C micro- and nanoresonators for sensors and wireless interfaces; (b) improve quality factor and output impedance using novel resonator devices.
Title:  A Micro Thermoelectric Cryogenic Cooler for MEMS
Graduate Students: Andrew J. Gross (EECS), Niloufar Ghafouri (EECS), Gisuk Hwang (ME) Funding Source: DARPA Post Doc: Hanseup S. Kim (EECS), Sang Woo Lee (EECS) Other Investigators: Massoud Kaviany (ME), Ctirad Uher (PHYS), Clark T. Nguyen (EECS-Berkeley)	Faculty Advisor: Khalil Najafi (EECS) Work Began: 03/01/2006
Project Goals:
A micro cryogenic cooler based on thermoelectric effects could have a major impact on critical military, medical, and consumer applications including substantial performance improvement of existing systems such as infrared detectors for military applications and localized quenching of biological tissues. Additionally, resonant MEMS, such as filters and gyroscopes benefit from an increase in quality factor at reduced temperatures. Because it has a lower efficiency than traditional cooling techniques, thermoelectric cooling has not been widely exploited for macro-scale cooling. However, for micro/nanoscale applications, efficiency may not be the most important technical consideration; rather size, total power consumption, and simplicity of fabrication and operation become critical issues. Because a thermoelectric micro cooler requires no moving parts or fluidic connections it could provide a robust solution for cooling a large variety of MEMS and IC-based microsystems. The ultimate goal of this project is developing a multistage micro thermoelectric cryogenic cooler capable of achieving a temperature of 160K, heat lift of up to a maximum of 5mW within a volume of less than 0.2cc, and using less than 100mW of power.
Title:  Wireless Monitoring of Intraluminal Prostheses
Funding Source: NSF GRF, WIMS ERC, other Post Doc: Scott R. Green (EECS)	Faculty Advisor: Yogesh B Gianchandani (EECS) Work Began: 06/01/2006
Project Goals:
This project seeks to apply batch-fabrication methodologies in the design and fabrication of stents with wireless integrated sensors. This integrated functionality will provide a direct method for monitoring the continued patency of the stented vessels and ducts, enabling timely intervention and allowing the avoidance of unnecessary procedures.
Title:  Locomotion Control of Insects Using Bulk Micromachined Thermal Actuators
Graduate Students: Karthik Visvanathan (ME), Naveen K. Gupta (ME) Funding Source: DARPA	Faculty Advisor: Yogesh B Gianchandani (EECS) Work Began: 12/05/2006
Project Goals:
This project aims at developing bulk micromachined thermal actuators for locomotion control of insects for microvehicle applications such as military surveillance and environmental monitoring. Applicability of both resistive and ultrasonic thermal actuators is investigated. This project also aims at further development of ultrasonic micromachining technology, which is used to machine ultrasonic microthermal actuators from bulk ceramic, such as PZT [1].
Title:  A Multistage Knudsen Pump Based on a Bulk Nanoporous Ceramic
Graduate Students: Naveen K. Gupta (ME) Funding Source: WIMS ERC	Faculty Advisor: Yogesh B Gianchandani (EECS) Work Began: 04/01/2007
Project Goals:
Although, research efforts over the past couple of decades have resulted in several promising micropumps, there is room for improvement in reliability, cost, drive voltage, etc. This project aims at using bulk nanoporous materials, such as the naturally occurring zeolites, nanoporous ceramics etc., for thermal transpiration-driven Knudsen pumping. Conceived almost a century ago, the Knudsen pump has long been a tantalizing target [1]. It is a gas pump with no moving parts and is driven by heat (Figure 1). It can be potentially small and reliable. The final goal of this research is: 1) to demonstrate the feasibility of bulk nanoporous materials for Knudsen pumping at atmospheric pressure, and 2) to design, test, and benchmark the Knudsen pump for its applicability to the WIMS Environmental Monitoring Testbed as compared to other gas pumps.
Title:  High-Force and Large-Deflection Electrostatic Hydraulic Microactuators
Funding Source: WIMS ERC Post Doc: Hanseup S. Kim (EECS)	Faculty Advisor: Khalil Najafi (EECS) Work Began: 01/01/2007 Project Completed: 08/31/2009
Project Goals:
High-performance microactuators have become increasingly critical components in many emerging microsystems as they provide unique, low-volume, low-power, and accurate interface among physical, fluidic, and electrical systems in the microdomain. Especially electrostatic actuators have been the most widely used due to easy fabrication, low-power consumption, high-speed response, and compatible interface with electronic systems; however, their performance has been mitigated due to the inherent trade-offs between the produced force and deflection: the electrostatic pulling force between the two electrodes becomes weak when the gap distance becomes wide to maximize the deflection distance. In this project, we propose to improve the performance of an electrostatic actuator for high-force and large-deflection applications by taking advantage of high dielectric constant and hydraulic momentum of fluids. The goals of this research are: 1) to develop microstructures and fabrication technologies that incorporate liquids for hydraulic systems and 2) to demonstrate its operation, such as high force and deflection, in the WIMS Environmental Monitoring Testbed.
Environmental Sensors & Subsystems
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Title:   Growth of Conformal CNT Adsorbent Layers for a Micro GC and Sensors
Funding Source: WIMS ERC Post Doc: Mudessar H. Shah (ECE-MSU) Other Investigators: Edward T. Zellers (EHS)	Faculty Advisor: Dean M Aslam (ECE-MSU) Work Began: 08/15/2006
Project Goals:
This project seeks to develop a technology for conformal deposition of high-density carbon nanotubes (CNTs) as adsorbent materials in the micropreconcentrator focuser (PCF) module of the WIMS micro gas chromatograph (GC). The work investigates the (a) effect of synthetic conditions on CNTs adsorption and desorption properties and (b) testing of PCF in commercial GC.
Title:  Testing and Evaluation of Microfabricated Columns
Graduate Students: Sung Jin Kim (ME) Funding Source: NASA ASTID Post Doc: Shaelah M. Reidy (CHEM) Other Investigators: Edward T. Zellers (EHS), Katharine T. Beach (EECS)	Faculty Advisor: Kensall David Wise (EECS) Work Began: 11/01/2001
Project Goals:
This project explores the use of high-performance, microfabricated columns with independent heating and temperature sensing for use in the development of a comprehensive, two-dimensional gas chromatograph (GC×GC).
Title:  INTREPID: An Application-Specific Micro-GC
Graduate Students: Gustavo Serrano (EHS) Funding Source: Department of Homeland Security Post Doc: Hungwei Chang (EHS)	Faculty Advisor: Edward T Zellers (EHS) Work Began: 05/01/2008
Project Goals:
This project concerns the design and fabrication of a gas chromatographic (GC) microanalytical system for near-real-time determinations of trace-level vapor concentrations of nitroaromatic explosives. This µGC, dubbed INTREPID, will capture and preconcentrate vapor samples, separate targets from interfering vapors, and identify and quantify them using a microsensor array. Ultimately, the system will be cell-phone-sized, have detection limits in the low parts-per-trillion range and perform a complete analysis every five minutes.
Title:  The MicroGeiger: A Micromachined Radiation Detector
Graduate Students: Christine K. Eun (EECS) Funding Source: Dept. of the Army, Micro Autonomous Systems and Technology Collaborative Technology Alliance	Faculty Advisor: Yogesh B Gianchandani (EECS) Work Began: 09/01/2002
Project Goals:
Wireless sensing capability is particularly useful for biohazardous environmental monitoring. In areas where concern for human exposure is a priority, the added flexibility a remote sensing scheme would provide dramatically increases the usefulness of present discharge-based sensors, in particular the microGeiger. Geiger counters are the detectors of choice when it comes to on-site surveillance of radioactive material. The goal of this project is to develop a new, wireless, sensing scheme for discharge-based sensors such as micromachined Geiger counters.
Title:  Sub-One-Degree Per Hour High-Performance Gyroscope
Graduate Students: Jae Yoong Cho (EECS) Funding Source: DARPA Post Doc: Sang Woo Lee (EECS)	Faculty Advisor: Khalil Najafi (EECS) Work Began: 01/01/2005
Project Goals:
Micro-gyroscopes are used in a variety of fields including military, automotive, guidance, and consumer products. By taking advantage of small-size, high-precision, highly reliable, and low-cost MEMS fabrication technologies, the resolution of the micro-gyroscope has steadily improved over the past two decades. However, the resolution of the conventional micro-gyroscopes is limited to above one-degree/hr, and its bandwidth reduces drastically as its resolution improves. This project aims to overcome these limits by developing a highly sensitive and environmentally resistant vacuum packaged micro-gyroscope with large bandwidth.
Title:  Microscale Integrated Sampler-Injector for a Micro GC
Graduate Students: Jung Hwan Seo (ME), Sun Kyu Kim (EHS) Funding Source: WIMS ERC Other Investigators: Edward T. Zellers (EHS)	Faculty Advisor: Katsuo Kurabayashi (ME) Work Began: 09/01/2006
Project Goals:
This project concerns the development of a passive microfabricated, integrated, sampler-injector (MISI) with integral thermal desorption heater. Advantage is taken of the microscale dimensions of the device components to achieve high (pumpless), effective sampling rates, high-preconcentration factors, and power-efficient desorption of ambient volatile organic vapors (VOCs). The goals of this project are to design, fabricate, and evaluate the performance of a prototype MISI, assess performance relative to theoretical models of diffusional transport and adsorbent capacity for vapors commonly found as contaminants in indoor working environments, and interface the sampler with an array of microsensors to determine the feasibility of incorporating the MISI into a microanalytical system for near real-time vapor determinations.
Title:  Breath Biomarker Determinations With a Portable Gas Chromatograph
Graduate Students: Sun Kyu Kim (EHS), Qiongyan (Judy) Zhong (EHS) Funding Source: Corporate Sponsor	Faculty Advisor: Edward T Zellers (EHS) Work Began: 08/15/2006 Project Completed: 10/31/2009
Project Goals:
This project was aimed at adapting a high-performance, prototype, portable gas chromatograph to the detection of volatile organic compounds (VOCs) in exhaled human breath. Breath analysis results could be correlated with the individual’s current health status, pre-clinical metabolic abnormalities, prescription drug effectiveness, and/or the presence of microbial activity/threats.
Title:  Thiolate-Monolayer-Protected Gold Nanoparticle Sensor Films for Explosives Detection
Funding Source: DHS Post Doc: Forest Bohrer (EHS)	Faculty Advisor: Edward T Zellers (EHS) Work Began: 10/03/2006
Project Goals:
This project entails the development of thiolate-monolayer-protected gold nanoparticles (MPNs) as interfacial films for chemiresistor (CR, thickness-shear-mode resonators (TSMR), and possibly other transducers. Mixed films of MPNs with metallophthalocyanines (MPcs) will be explored for detection of peroxides. Testing will assess various performance features of single-transducer and multi-transducer arrays for ultimate incorporation into a µGC capable of rapid determinations of such target vapors in complex mixtures. Targeted explosives and tagants include nitroaromatic compounds such as trinitrotoluene (TNT) and 2,4-dinitrotoluene (2,4DNT), as well as peroxide-based explosives such as triacetone triperoxide (TATP) and hydrogen peroxide. Chemometric methods will enable identification of explosive compounds.[3]
Title:  Fundamental Aspects of Nanoscale, Multimodal Sensor Arrays
Graduate Students: Elizabeth L. Covington (PHYS) Funding Source: DHS Post Doc: Forest Bohrer (EHS) Other Investigators: Edward T. Zellers (EHS)	Faculty Advisor: Cagliyan Kurdak (PHYS) Work Began: 01/01/2007
Project Goals:
The project addresses challenges of miniaturizing vapor sensors employing monolayer-protected Au-thiolate nanoparticles (MPN) as interface layers on transducers formed from simple interdigital electrodes. An emphasis is placed on detection of explosives, tagants, and related compounds. Fundamental limits of detection will be defined by combining measurements of noise and vapor sensitivity from a wide range of MPNs and transducer dimensions. The multimodal operation (i.e., simultaneous measurements of resistance and capacitance) of the sensors will also be explored. We will test whether we can improve the limit of detection by reducing the sensor size.
Title:  On-Chip Auto Calibrating Impedance Analysis for Gas Sensors
Graduate Students: Xiaoyi Mu (ECE-MSU), Yuning Yang (ECE-MSU) Funding Source: WIMS ERC, Department of Homeland Security	Faculty Advisor: Andrew J Mason (ECE-MSU) Work Began: 01/01/2007
Project Goals:
Chemiresistors (CR) coated with Au-thiolate monolayer protected nanoparticles (MPN) exhibit a highly sensitive resistance change in response to absorbed vapors and provide extremely low detection limits to vapors. The practical limitations to MPN-based CR sensor resolution are due to the precision of measurement circuits and noise sources in the transducer and electronics. This project aims to develop a microelectronic instrumentation circuit that will maximize measurement precision and minimize electronic noise within a platform suitable for monolithic integration of a gas sensor array microsystem. The chemiresistor also has a theoretical capacitive response which has been difficult to investigate, again due to noise and parasitics. The second goal of this project is to extend the interface circuit to allow full impedance measurements which would be able to characterize both the resistance and capacitance of the chemiresistor.
Title:  Integrated Particle Counting and Potentiometric Sensor Array for Water Quality Analysis
Graduate Students: K. Jeff Campbell (ECE-UT) Funding Source: NIH Grant/ARUP Labs	Faculty Advisor: Richard B Brown (ECE-UT) Work Began: 09/19/2005
Project Goals:
This project will implement an all-electronic potentiometric and particle sensor array. A manufacturing process which facilitates mass-fabrication of nanopore sensors atop CMOS circuitry will be developed. Integrated electronics will greatly reduce the number of external connections between sensor and instrument, reducing noise and improving power budget. The microstructure is also expected to be robust and offer improved reliability over existing sensors. Finally, the performance of completed sensors will be characterized, and the behavior of an array of sensors will be optimized.
Title:  Multi-Transducer Arrays for a Micro GC Detector
Funding Source: Corporate Sponsor Post Doc: Forest Bohrer (EHS)	Faculty Advisor: Edward T Zellers (EHS) Work Began: 09/10/2006 Project Completed: 08/01/2009
Project Goals:
This project explores the development of multi-transducer arrays as detectors for a µGC system. Chemiresistors (CR), film-bulk-acoustic resonators (FBAR), and thickness-shear-mode resonators (TSMR) coated with gold-thiolate monolayer-protected nanoparticles (MPNs) are being explored [1]. This project is being expanded to include tin oxide (SnO2) nanowire sensors. The information about sorbed vapors provided by the respective transducer types is complementary.
Title:  A MEMS Gas Chromatograph
Graduate Students: WIMS EMT Team Funding Source: WIMS ERC Other Investigators: Robert J. Gordenker (EECS)	Faculty Advisor: Edward T Zellers (EHS) Work Began: 09/01/2005
Project Goals:
The WIMS EMT team is realizing the assembly and optimization of high-performance micro gas chromatograph (µGC) solutions capable of capturing, preconcentrating, separating, and detecting the components of complex environmental vapor mixtures. Projects focus on µGCs designed for the detection of trace levels of trichloroethylene (TCE) in the presence of VOC interferences found in homes, µSystems for the rapid detection of explosives and solutions for the separation of bio-markers in human breath and highlight applications in homeland security and medical surveillance. µGCs designed to separate complex vapor mixtures demonstrate the versatility and operating range of the technology.
Title:  A Miniaturized, Robust, High-Speed Thermal Modulator for Comprehensive 2-D Gas Chromatography
Graduate Students: Sung Jin Kim (ME) Funding Source: NASA Other Investigators: Edward T. Zellers (EHS), Kensall D. Wise (EECS)	Faculty Advisor: Katsuo Kurabayashi (ME) Work Began: 04/01/2006
Project Goals:
The goal of this project is to develop a key subcomponent of the microfabricated GC×GC system, a thermal modulator (TM), using MEMS technology. In general, TMs are crucial to achieve high sensitivity in the GC×GC system by providing 10-to-50-fold detection enhancement. This project aims to design, fabricate, and test a MEMS-based thermal modulator that can be integrated with microfabricated 2-D GC columns and generate heating and cooling cycles between -50°C and 200°C within a few hundred milisecond timescales. A microfabricated heater pattern is used for heating, and cooling is achieved by conduction to a cold surface. Thermal resistance to the cold surface can be tailored using air-gap insulators. Significant technological advances are being explored to reduce space, mass, and power resources required for the organic vapor separation process with a MEMS-based TM device. The system incorporating the TM provides the opportunity to conduct complex in situ sample analysis with minimal temperature control requirements.
Title:  Integrated Porous Silicon Technology for a Micro Gas Chromatograph (µGC)
Graduate Students: Lakshman Kumar Vanga (ECE-MTU) Funding Source: WIMS ERC Other Investigators: Edward T. Zellers (EHS)	Faculty Advisor: Paul L Bergstrom (ECE-MTU) Work Began: 10/09/2005
Project Goals:
Porous silicon technologies for the Environmental Monitoring Testbed are explored in this research. A high-efficiency, inlet particulate filter, the on-board calibration standard vapor source (RCS), and a novel preconcentrator/focuser device (PCF) have been developed in porous silicon for the micro gas chromatograph (µGC). The preconcentrator/focuser device is a two-layered structure consisting of a diffusive channel made of porous silicon (PS) and a cavity region to hold the preconcentrator materials (adsorbents). The prominent features of the design include the effective sampling of the gas species and power-efficient desorption of volatile vapors.
Title:  Integrated Low-Power, High-Pressure, High-Flow Gas Micropump
Graduate Students: Ali Besharatian (EECS), Seow Yuen Yee (EECS) Funding Source: WIMS ERC Other Investigators: Luis P. Bernal (AERO)	Faculty Advisor: Khalil Najafi (EECS) Work Began: 05/01/2007
Project Goals:
An efficient, low-power, high-flow, high-pressure, and small-volume gas micropump is needed in many emerging microsystem applications, such as a micromachined gas chromatograph µGC). Especially the WIMS µGC needs a pump that supports the two different operation modes of the µGC: sampling and analysis. Previous gas micropumps have shown only limited capabilities, such as low flow rate, low pressure, and large volume, thus failing to meet the requirements of the WIMS µGC. In a recently completed project, a micromachined pump has been developed and has demonstrated for the first time that a much higher flow rate and pressure could be produced. In this project, we propose to continue developing this micropump to achieve a higher pressure and higher flow rate than achieved to date. The goals of this research are: 1) to develop a high-performance gas micropump overcoming the limitations of previous micropumps and 2) to demonstrate its operation in the WIMS Environmental Monitoring Testbed.
Title:  A Low-Volume, Low-Power, Preconcentration and Separation System
Funding Source: WIMS ERC Post Doc: Shaelah M. Reidy (CHEM) Other Investigators: Anastasios J. Hart (ME), Edward T. Zellers (EHS)	Faculty Advisor: Kensall David Wise (EECS) Work Began: 06/01/2007
Project Goals:
A truly low-power, low-dead-volume, high-speed, gas separation system continues to be one of the most important goals of the WIMS ERC. Achieving this goal has been hampered by fluidic interconnects that require capillary lines since these increase system size and power and create cold spots that lead to band broadening and reduced separation. The goal of this project is to eliminate the need for capillary connections between the preconcentrator, separation columns, and detector, realizing an integrated three-chip separation system that can be used as a building block for all future high-performance microGC systems.
Title:  Low Dead Volume Gas Detection System
Funding Source: ERC Other Investigators: Katharine T. Beach (EECS)	Faculty Advisor: Kensall David Wise (EECS) Work Began: 06/01/2007
Project Goals:
The intergration of the varoius components that make up the Environmental Testbed has been one of the long term goals of the WIMS ERC. This goal has been hampered by interconnection issues that have required long lines of capillary tubes. This project focuses on eliminating the need for capillary connection between the miro preconcentrator and GC. Goals: Lower mass/power precon, more robust CVD GC,choose your size pre-con, complete separation part of the system that is small and low power, increased device yield,
Title:  High Performance Portable GC for Trichloroethylene Vapor Intrusion Monitoring
Graduate Students: Sun Kyu Kim (EHS), Thitiporn Sukaew (EHS) Funding Source: IST, Inc. (Dept. of Defense, prime)	Faculty Advisor: Edward T Zellers (EHS) Work Began: 01/05/2009
Project Goals:
This project is aimed at adapting a high-performance prototype portable gas chromatograph (meso-GC), employing a nanoparticle-coated chemiresistor array detector, for the effective determination of trichloroethylene (TCE) vapors at sub-ppb concentrations in the presence of interferences encountered in homes affected by vapor intrusion (VI) from TCE-contaminated soil. Knowledge obtained from this study will be transferred to the µGC, SPIRON-A which is being adapted for the same problem.
Title:  Automated Control Systems for Micro-GC Operation
Funding Source: DHS Post Doc: Hungwei Chang (EHS)	Faculty Advisor: Edward T Zellers (EHS) Work Began: 06/01/2008
Project Goals:
This project concerns the development and implementation of software control functions applicable to all of the µGC prototypes being developed for the WIMS EMT. Functions include preconcentrator heating, column temperature programming, valve actuation, sensor thermostating, acquisition of responses from the sensor array, and scheduling all events according to user definable needs. Using the Labview programming environment, custom packages are being developed for the JUPITER, INTREPID, SPIRON, and ORION microsystems.
Title:  Micro GC Prototype for VOCs in Breath
Graduate Students: Sun Kyu Kim (EHS) Funding Source: WIMS ERC Post Doc: Hungwei Chang (EHS)	Faculty Advisor: Edward T Zellers (EHS) Work Began: 04/20/2008
Project Goals:
The goal of this project is to develop a gas chromatographic microanalytical system (µGC) specifically tailored for analyzing volatile organic compounds (VOC) in human breath. This microsystem, dubbed SPIRON-B, will incorporate MEMS preconcentration, dual-column separation, and microsensor array detection devices into an integrated package that will perform complex-VOC analyses of breath biomarkers of disease and metabolic status. The system will ultimately be laptop sized, driven by a notebook computer based controller, and useful for clinical, bedside, or home diagnoses.
Title:  Micro-GC for Vapor Intrusion Applications
Graduate Students: Sun Kyu Kim (EHS), Thitiporn Sukaew (EHS) Funding Source: Corporate Sponsor (Dept. of Defense, prime) Post Doc: Hungwei Chang (EHS)	Faculty Advisor: Edward T Zellers (EHS) Work Began: 12/01/2008
Project Goals:
This project entails the development of a prototype micro gas chromatograph (µGC), referred to as SPIRON-A, for the determination of parts-per-trillion concentrations of volatile organic compounds (VOCs) arising from vapor intrusion (VI) in homes situated above contaminated soil and groundwater. The primary VI target compound is trichloroethylene (TCE), which must be determined at concentrations of 0.04ppb in the presence of common interferences in an analytical cycle period of <30 minutes. A series of 4 fully functional prototypes will be assembled and field tested in actual homes in Utah.
Title:  Development of a Multi-Stage Preconcentrator/Focuser Module for a µGC
Graduate Students: Thitiporn Sukaew (EHS) Funding Source: Corporate Sponsor (Department of Defense, prime)	Faculty Advisor: Edward T Zellers (EHS) Work Began: 05/01/2009
Project Goals:
This project seeks to characterize a series of adsorbent preconcentrators to be integrated into one of the prototype micro gas chromatographs (µGC) being developed in collaboration with researchers in the WIMS Center. This prototype, called the SPIRON-A µGC, is being developed for in situ determinations of trichloroethylene (TCE) vapors in homes at risk for vapor intrusion (VI) from surrounding TCE-contaminated soil and ground water. The target detection limit and analytical cycle time are 0.04 ppb and 15 minutes, respectively. To achieve these goals requires sampling a relatively large volume of air in a short period of time, exclusion of higher-boiling interferences, and focused injection into the separation module of the µGC. We will use an adsorbent pre-trap to exclude unwanted high-boiling interferences, a sampler to capture TCE quantitatively at a high flow rate, and a micro-focuser (shown to the right) for thermal desorption/injection onto the µGC column. The goals of the project are to determine the best adsorbent materials to use in each device, the flow rate limitations and TCE capacities, humidity effects, and desorption efficiencies and desorption bandwidths. Optimizing performance and integrating this subsystem with the other components of the SPIRON-A µGC are planned.
Title:  Integrated Microfluidic Detector Cell for µGC Vapor Sensors
Graduate Students: Diana Ramos (ECE-MSU) Funding Source: Department of Homeland Security	Faculty Advisor: Wen Li (ECE-MSU) Work Began: 07/01/2009
Project Goals:
The integration of a microfluidic detector cell onto the same substrate where the nanoscale sensor array and sensor-readout circuitry are fabricated is challenging due to small device dimensions and material sensitivities. This project aims to develop and fabricate a microscale detector cell for the integrated nanoscale sensor array. The detector cell will have small physical dimensions to minimize the dead volume without compromising the sensitivity and stability of the enclosed sensor. Integration method needs to allow fluidic interconnections (via capillaries or micrmachined conduit) to an upstream µGC column and to downstream pump or reference detectors. Materials used for the micofabrication of the cell should be inert enough toward sorption of vapor phase analytes and interferences to serve as an effective detector housing material.
Biomedical Sensors & Subsystems
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Title:  Diamond Probes for Neural Applications
Graduate Students: Michael W. Varney (ECE) Funding Source: WIMS ERC Post Doc: Ho-Yin Chan (ECE-MSU) Other Investigators: Kensall D. Wise (EECS)	Faculty Advisor: Dean M Aslam (ECE-MSU) Work Began: 09/01/2006
Project Goals:
This project focuses on the design, fabrication, optimization, and testing of a polycrystalline diamond (poly-C) probe for applications in neural studies. It also focuses on the development and improvement of poly-C technology in other biomedical and electrochemical applications.
Title:  A Cochlear Prosthesis Insertion Device Based on a Retractable and Active Insertion Tool
Graduate Students: Radheshyam Tewari (MEEM-MTU) Funding Source: WIMS ERC	Faculty Advisor: Craig R Friedrich (ME-MTU) Work Began: 09/14/2007
Project Goals:
The actuators used for the WIMS ERC cochlear arrays provide a structural backing and hence the required rigidity for maintaining the perimodiolar shape. The dependency of the implant’s performance by the actuator makes it mandatory to leave the device after the implantation. This results in bulkier devices making the fluid-filled tympanic chamber more congested. Instead of backing implants directly with the pneumatically actuated positioner, the proposed method will be a detachable tool attached to the implant.
Title:  Wireless Neural Recording System and Software at Low Cost
Graduate Students: Jeff Gregory (EECS) Funding Source: NIH	Faculty Advisor: Khalil Najafi (EECS) Work Began: 09/01/2007
Project Goals:
We are developing a stand-alone, wireless microsystem for recording and transmission of multichannel neural signals from unrestrained subjects. These wireless microsystems have a wide range of biomedical applications, and should be small, lightweight, and portable. Wired neural recording requires observation in restrained environments, which may limit the test subject’s natural activities and social interactions. Wireless recording systems have found limited application however, in part because of the high cost and limited functionality. A successful system will have good range, small size compared to the test subject, moderate channel count and robust transmitter, and receiver hardware and software. Initially, the project’s goal is to build and implement very small wireless units designed and built using off-the-shelf components. In the longer term (2–3 years), these systems will be designed using custom IC technologies to reduce size, weight, and power even further.
Title:  A Microsystem for Neurochemical Sensing
Graduate Students: Robert K. Franklin (EECS) Funding Source: NIH NIBIB Grant EB005022-01A1 Other Investigators: Daryl R. Kipke (BME)	Faculty Advisor: Richard B Brown (ECE-UT) Work Began: 01/01/2005
Project Goals:
The goal of this project is to develop a fully implantable, neurochemical monitoring microsystem based on MEMS brain-probe technology developed at the University of Michigan.
Title:  A Wireless Implantable Microsystem for Multichannel Neural Interfacing
Graduate Students: Sister Mary Elizabeth Merriam (EECS) Funding Source: WIMS-ERC	Faculty Advisor: Kensall David Wise (EECS) Work Began: 10/01/2004
Project Goals:
Chronic recording of multichannel neural electrical activity using microprobes is widely used for understanding the operation of the nervous system and for implantable prostheses. This project deals with the design and implementation of an implantable microsystem for wirelessly interfacing to the cortex of the brain. The system uses a bidirectional inductively-coupled RF telemetry link that provides power and control to the implant in the forward direction and transmits recorded neural signals to the outside world in the reverse direction. Figure 1 illustrates the general architecture of the wireless implantable microsystem.
Title:  High-Throughput, Single-Cell Assay Chip for Cancer Drug Screening
Graduate Students: Jaehoon Chung (EECS) Funding Source: National Cancer Institute Prostate SPORE Post Doc: Tom Bersano (EECS)	Faculty Advisor: Euisik Yoon (EECS) Work Began: 07/01/2008
Project Goals:
There have been growing interests in a single-cell assay, and a few groups have reported the microfluidic chips that incorporate single-cell capturing schemes. However, their capturing efficiency (the ratio of the total captured cells to the injected cells) is relatively poor (less than a few %) and may not be adequate for handling rare cells such as stem cells or cancer cells. The goal of this project is to design and fabricate a microfluidic platform which can capture cells with very high efficiency at a single-cell resolution into a large microwell array and simultaneously apply different reagents for various single-cell assays.
Title:  A High-Density Mechanically Robust Cochlear Electrode Array With Multiple Site Configurations
Graduate Students: Angelique C. Johnson (EECS) Funding Source: WIMS ERC Other Investigators: Bryan E. Pfingst (OTO), Teresa A. Zwolan (OTO), Craig R. Friedrich (ME-MTU)	Faculty Advisor: Kensall David Wise (EECS) Work Began: 05/01/2006
Project Goals:
This project is developing a 128-site, 16-channel batch fabricated electrode array as a cochlear prosthesis for the profoundly deaf. By placing the electrical stimulation sites in a high-density configuration (250µm pitch), this device offers the potential for greater frequency resolution, leading to enhanced speech recognition. In creating the electrode array, planar IC processing techniques are being investigated to achieve tighter dimensional control and smaller array size along with new features such as position and wall-contact sensing. Parylene substrates are being investigated to increase the robustness of the cochlear array and the cable that interfaces it to the electronics. Monolithic backing and curl enhancements are being designed to tailor the array stiffness and modiolar-hugging ability. The interface circuitry is being redesigned to allow greater versatility in site selection using monopolar, bipolar, and tripolar configurations.
Title:  A Wireless Sub-Microwatt Intraocular Pressure Sensor
Graduate Students: Razi-ul M. Haque (EECS) Funding Source: WIMS ERC Other Investigators: Dennis M. Sylvester (EECS)	Faculty Advisor: Kensall David Wise (EECS) Work Began: 01/03/2006
Project Goals:
This project explores technologies that, when combined, will demonstrate the practicality of very small, ultra-low-power, wireless implantable sensors. The target application is an intraocular pressure sensor capable of autonomous data logging and wireless communication. The device demands very small size (2mm × 1mm × 0.5mm), biocompatibility, and ultra-low power. Challenges include the power source and methods for recharging it, wireless transmission techniques that are efficient at low data rates yet robust enough to transmit signals out of the body, and packaging techniques that reduce size while maintaining biocompatibility and hermeticity.
Title:  A Lightweight Bidirectional Wireless Neural Recording and Control Microsystem
Graduate Students: Amir Borna (EECS) Funding Source: NIH	Faculty Advisor: Khalil Najafi (EECS) Work Began: 01/01/2006
Project Goals:
The primary goal of this project is to collect biological information from freely flying songbirds, and specifically from the Zebra Finch. To understand the role of experience in modifying the brain, songbirds are one of the best models to study due to the fact that the male specie can learn his father’s song by a process of imitation which is independent of genetic ties between the birds (S. Overduin, 2003). To collect the biological data, extracellular neural activity sensed by electrodes implanted in the host’s forebrain, should be processed and transmitted out over a wireless link to a remote receiver by a lightweight, low-power, and long-range transceiver capable of both sending and receiving data and power.
Title:  System Integration for the Cochlear Prosthesis Testbed
Graduate Students: Nathaniel C. Gaskin (ECE-UT), Spencer S. Kellis (ECE-UT) Funding Source: WIMS ERC	Faculty Advisor: Richard B Brown (ECE-UT) Work Began: 12/18/2005
Project Goals:
Integrate the WIMS microcontroller, the Hybrid Cochlear ASIC, and the telemetry chip to create a low-power, implantable system for cochlear prosthesis applications. Build a system on which to run the tone and current-shaping demonstrations to showcase the electrical functionality of the microsystem.
Title:  A 3-D Bidirectional Interface for Neural Mapping Studies
Graduate Students: Sister Mary Elizabeth Merriam (EECS) Funding Source: WIMS ERC and the Polly Anderson Gift Fund Other Investigators: Susan E. Shore (OTO)	Faculty Advisor: Kensall David Wise (EECS) Work Began: 07/01/2007
Project Goals:
A WIMS microsystem is being developed in order to provide neuroscientists with the necessary research devices to enable and expedite continued progress in understanding the anatomy and physiology of the brain, with particular focus on mapping the complex connections of neural circuitry. This research is developing a system which incorporates three-dimensional arrays of recording and stimulating sites with hybrid circuitry to provide flexible site selection, reduced lead counts, and enhanced signal-to-noise ratios.
Title:  Protein-Based Biosensor Array Microsystem
Graduate Students: Xiaowen Liu (ECE-MSU), Lin Li (ECE-MSU) Funding Source: NSF	Faculty Advisor: Andrew J Mason (ECE-MSU) Work Began: 09/01/2007 Project Completed: 09/01/2009
Project Goals:
The goal of this multidisciplinary project is to develop an integrated microsystem platform that incorporates a bio-interface array into a cost-effective, continuous-use, electrochemical characterization system suitable for functional proteomics research.
Title:  A Neural Signal Processor for Wireless Implants
Graduate Students: Awais M. Kamboh (ECE-MSU), Yuning Yang (ECE-MSU) Funding Source: National Institutes of Health	Faculty Advisor: Andrew J Mason (ECE-MSU) Work Began: 08/15/2008
Project Goals:
This project aims at compressing real-time neural data recorded from microelectrode arrays, from a large number of channels for wireless transmission to an external processing unit, while maintaining the shape of neural spikes so as to enable high-quality spike sorting at the receiver. The compression and transmission of this data needs to be power efficient to keep tissue temperatures low. The system also has to be area efficient for surgical reasons.
Title:  Dual-Mode Proximity Sensor for Artificial Robot Skin
Graduate Students: Sun-Il Chang (EECS) Funding Source: CIR Post Doc: Il-Joo Cho (EECS)	Faculty Advisor: Euisik Yoon (EECS) Work Began: 04/01/2008 Project Completed: 03/31/2009
Project Goals:
The evolution of robot engineering has made spectacular progress for the past decade, especially in the area of humanoids as we can see in HUBO [2] or ASIMO [3]. Some commercial robots are available such as Roomba, although they are still in a primitive form of assistant robots [4]. Many researches are underway developing robots which can help humans, especially the handicapped or the elderly. In order for those robots to interact with human beings and the environment safely, it is imperative to be able to detect not only tactile information but also proximity of objects or obstacles before they are too close. This function will prevent the robots from accidental collision which can bring damage to humans or to robots themselves. Also, it is desirable to integrate sensors in a unified platform, as much as possible, to reduce hardware burden. There have been various proximity sensors for robots such as ultrasonic, infrared, and capacitive sensors [5-7]. Among them, a capacitive proximity sensor is suitable for integration as it consists of simple electrodes only.
Title:  Electrochemical Microsystem Array for Functional Proteomics
Graduate Students: Lin Li (ECE-MSU), Xiaowen Liu (ECE-MSU) Funding Source: NSF	Faculty Advisor: Andrew J Mason (ECE-MSU) Work Began: 09/01/2007
Project Goals:
The goal of this multidisciplinary project is to develop an integrated microsystem platform that incorporates a bio-interface array into a cost-effective, continuous-use, electrochemical characterization system suitable for functional proteomics research. This device would provide revolutionary capabilities for protein characterization, including (1) simultaneous activity measurement for many soluble and membrane proteins, (2) rapid, automated interrogation using multiple electrochemical techniques, (3) microthermoregulation of individual protein sites, and (4) reduced costs per assay. To achieve this goal, we plan to develop microfabrication techniques for a miniaturized, multi-protein, array-on-chip platform that incorporates microfluidics and temperature control of individual electrodes, and to develop integrated circuit with range/sensitivity adaptive multi-mode electrochemical readout and thermal feedback control.
Title:  Microfluidic Array for High-Throughput Single-Cell Assay
Graduate Students: Young-Ji Kim (EECS), Xia Lou (EECS) Funding Source: KIST Cell Post Doc: Tom Bersano (EECS)	Faculty Advisor: Euisik Yoon (EECS) Work Began: 07/01/2008
Project Goals:
There have been growing interests for single-cell assays to understand single-cell behavior more accurately. This is due to the fact that cellular response from conventional assays provides only collective average data from a large group of cells, while it is well known that the cells of identical appearance under seemingly identical conditions may show different characteristics. The distribution of cell response is closely connected with culture environments such as biological signals induced from cell contact conditions, including cell-cell communications, and cell-extracellular matrix (ECM), chemical signals, and physical signals. Also, nonuniform distribution of cell population using conventional culture methods results in different culture environment of cells and may result in different behaviors of cells [1-3]. In this project, we will bring substantial values which are essential to understand and study the optimal conditions of muscle stem cell self-renewal, proliferation and differentiation at a single-cell level through developing a generic microchip platform. We will develop the microchips which have unique features in single-cell manipulation and fluidic control.
Title:  A Low-Power Area-Efficient 8 Bit SAR ADC Using Dual Capacitor Arrays for Neural Microsystems
Graduate Students: Sun-Il Chang (EECS) Funding Source: WIMS ERC	Faculty Advisor: Euisik Yoon (EECS) Work Began: 09/01/2008 Project Completed: 08/01/2009
Project Goals:
Recently, multichannel neural interface systems have been implemented to monitor neural activities. For the comprehensive analysis of neural activities [1,2], it is essential to realize Simultaneous Real-time Monitoring of multiple sites in Multichannel Implantable Neural Systems. Neural activities such as spike contain most of information in the bandwidth Below 10 kHz with maximum amplitude of ±500μV. For the analysis of the neural activities, the recorded signal is transmitted to Wired / Wireless Communication Channels between the implanted system and the external world.
Wireless Interfaces
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Title:  Low-Power Transmitter for Wireless Sensor Networks
Graduate Students: Mark A. Ferriss (EECS) Funding Source: WIMS ERC, MAST Research Center	Faculty Advisor: Michael P Flynn (EECS) Work Began: 09/01/2003 Project Completed: 05/01/2009
Project Goals:
The aim of this research is to develop wireless transmitter architectures for low-power sensor nodes and to develop new circuit design techniques to allow for more efficient power RF circuits. Existing transmitters for proprietary wireless technologies (e.g., Bluetooth) consume too much power for these applications. Consequently, this work will also focus on minimizing cost, size, complexity, and power.
Title:  Low-Power MICS Transceiver
Graduate Students: James D. Griggs (ECE-NCAT), Zheng Wang (ECE-NCAT) Funding Source: WIMS ERC Other Investigators: Michael P. Flynn (EECS)	Faculty Advisor: Numan S Dogan (ECE-NCAT) Work Began: 03/01/2005
Project Goals:
A low-power Medical Implant Communication Service (MICS) transceiver is being developed. Stringent low-power requirements for implant electronics dictate power/performance optimization. A 0.18 micron RF/Mixed-Signal CMOS process is used for the design and implementation of a single-chip MICS transceiver. Our current target power consumption is 5mW from a 1 Volt supply. Sleep mode will be employed to reduce power consumption during idle times. MICS occupies the frequency spectrum from 402MHz to 405MHz.
Title:  Design of a Low-Power Wireless Sensor for Monitoring and Control of Complex Engineered Systems
Graduate Students: Raymond A. Swartz (CEE), Andrew T. Zimmerman (CEE), Sukhoon Pyo (CEE) Funding Source: WIMS ERC	Faculty Advisor: Jerome Peter Lynch (EECS/CEE) Work Began: 04/01/2005
Project Goals:
In response to the technical challenges encountered during field instrumentation of wireless sensors in civil structures, this study seeks to improve the power efficiency of wireless sensing units for structural monitoring and control. In addition to improving unit power efficiency, the study simultaneously introduces a sophisticated network media access protocol (MAC) to improve the scalability of wireless sensor networks installed in large-scale civil structures. By leveraging the IEEE802.15.4 communications standard, wireless sensors will be able to form scalable, ad-hoc networks for structural monitoring and control. This study is also exploring novel approaches for distributed dynamic control of civil structures utilizing the wireless communication channels in an efficient, power-aware manner. Finally, a key goal of the project is the embedding of engineering algorithms for distributed, in-network data analysis using sensed data.
Title:  Self-Calibrating Moderate Resolution Analog-to-Digital Converters
Graduate Students: Andres A. Tamez (EECS), Joshua J. Kang (EECS), Nicholas A. Collins (EECS) Funding Source: WIMS ERC	Faculty Advisor: Michael P Flynn (EECS) Work Began: 05/01/2004
Project Goals:
The accuracy of SAR analog-to-digital converters is deteriorated by mismatch in the DAC capacitor array. For a 10-bit converter, the SAR array consists of 210(1024) capacitors. Our goal is to identify a calibration algorithm that can be implemented on-chip to calibrate the capacitor array to yield the best ADC performance. The technique will be extended to a 12-bit ADC.
Title:  Power-Efficient ADC in Nanometer CMOS Technology
Graduate Students: Chun C. Lee (EECS) Funding Source: NSF Career, Intel Fellowship, WIMS ERC	Faculty Advisor: Michael P Flynn (EECS) Work Began: 01/01/2005
Project Goals:
The goal of this project is to develop a novel power-efficient technique for Analog-to-Digital Conversion (ADC) in digital nanometer CMOS processes. Current state-of-the-art CMOS integrated circuit (IC) processes are ideally suited for implementing digital circuits; but they do not deliver the precision and accuracy required for high-resolution analog design. This is because the transistors have poor analog properties (such as linearity and gain), and the shrinking of the supply voltage makes the matter worse. The Analog-to-Digital Converter (ADC) is a key analog component in most applications. Thus, new techniques need to be developed to design ADCs in these new IC processes. Furthermore, the performance requirements (in terms of resolution, speed, and power) of such ADCs need to increase for newer applications. A key goal is to develop an ADC scheme that is efficient enough to make a digital-dominant receiver feasible for sensor network and WLAN applications.
Title:  RF Front-End for Gen3 WIMS Microcontroller
Graduate Students: Ondrej Novak (ECE-UT), Wei Wu (ECE-UT) Funding Source: University of Utah Seed Grant	Faculty Advisor: Cameron T. Charles (ECE-UT) Work Began: 11/01/2007
Project Goals:
The primary objective of this project is to design and implement an Ultra-Wide Band (UWB) RF transceiver that provides a wireless interface between the sensor probes and Gen-3 WIMS microcontroller unit. The target application for this transceiver is use with an array of neural probes (such as shown in Figure 1) that require high-data-rate communication in the order of 5-10Mb/s with very-low-power consumption. This system-on-a-chip approach with RF and mixed-signal systems on the same die will reduce the power dissipation of the system. It also offers advantages in size and weight, which provide the most important attributes of any portable device. This single-chip, mixed-signal solution provides benefits of low-power consumption by decreasing the amount of required buffers to drive off-chip loads, including pads and bonding wires, and printed circuit board traces.
Title:  Analog-Digital Conversion for Very-Low-Power Transceivers
Graduate Students: Shahrzad Naraghi (EECS) Funding Source: WIMS ERC	Faculty Advisor: Michael P Flynn (EECS) Work Began: 06/01/2005 Project Completed: 07/01/2009
Project Goals:
Low-power, small-size, analog-to-digital converters (ADC) have numerous applications in areas ranging from implantable biomedical devices to power-aware wireless sensing nodes for environmental monitoring and point-of-care diagnostics. This work focuses on ultra-low-power and very-compact implementation of ADCs in nanometer CMOS technologies. We explore time-based techniques, which achieve significant reductions in power consumption and silicon chip area compared to today’s state-of-the-art architectures.
Title:  Digital Dominant Radio Receiver in Nanometer CMOS
Graduate Students: David T. Lin (EECS), Li Li (EECS) Funding Source: WIMS ERC, Semiconductor Research Corporation	Faculty Advisor: Michael P Flynn (EECS) Work Began: 05/01/2007
Project Goals:
Wireless radio receivers have traditionally been designed to target a particular communication standard (e.g., GSM, 802.15.4, 802.11). This design approach is inefficient, because the receiver has to undergo costly and time-consuming redesign whenever the prevailing standard changes. A solution is to design a digital dominant receiver, in which analog and digital circuitry is combined to create hardware that supports a range of specifications. Another benefit of digital programmability is the ability to adjust power consumption and performance in real time, in response to environmental conditions. This project seeks to design a flexible, low-power, and low-cost digital dominant wireless receiver in nanometer CMOS.
Title:  End of the CMOS Scaling Roadmap ADCs
Graduate Students: Jorge A. Pernillo (EECS) Funding Source: Intel	Faculty Advisor: Michael P Flynn (EECS) Work Began: 08/01/2006
Project Goals:
Our goal is to investigate new approaches to analog-to-digital conversion that are suited for end-of-the-roadmap CMOS, and which also deliver orders-of-magnitude improvements in speed and energy efficiency. We break analog-to-digital conversion down to its essence and simplify the process of analog-to-digital conversion to its most basic form. This allows us to take advantage of the tremendous digital capability of nanometer processes and then implement the analog circuitry in the simplest way.
Title:  60 GHz Frond-Ends in CMOS for Wireless Sensor Network Applications
	Work Began: 01/01/2009 Project Completed: //