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Special Report
Bradley Fellow/Scholar Alumni

 April 2001


Electronics Research

Associated Laboratories and Centers:
Center for Power Electronics Systems
Microelectronics, Optoelectronics and Nanotechnology (MicrON) Group
Wireless Microsystems Laboratory

Representative Electronics Research Projects


Center for Power Electronics Systems (CPES)

ECE Faculty
Fred Lee, Director
Dushan Boroyevich, Deputy Director
Dan Chen
Alex Huang
Jason Lai
G.Q. Lu
Daan van Wyk

Established in August 1998, CPES is one of the nation's relatively few NSF engineering research centers. Members of CPES include five universities, 25 core faculty members, and 90 industrial partners. The other four CPES universities are the University of Wisconsin-Madison, Rensselaer Polytechnic Institute, North Carolina A&T State University, and the University of Puerto Rico-Mayagüez.

Financial support for CPES during its first two years of operation exceeded $20 million, which includes associated grants and contracts, cost sharing and membership fees. These funds are used to support the three programmatic elements of CPES: (1) technology development and demonstration; (2) industrial collaboration and technology transfer; and (3) education and outreach.

CPES's program for technology development and demonstration relies heavily on participation by industry, and is designed to cover several areas which includes advanced power semiconductor devices; systems integration; advanced power electronics packaging technology; control and sensor integrations; and integrated power electronics module synthesis (IPEMS).

In the CPES demonstrative program, two initiatives are in place to demonstrate the viability of the technology being developed. These two initiatives address distributed power systems and motor drives. The research prototypes for the demonstrative initiatives are being built using a two-tier testbed approach. The first tier takes place in a university-based experimental testbed to evaluate "proof-of-concept" prototypes, and the second tier takes place within an industrial setting to determine the feasibility and value for commercialization of existing applications.

The second area of CPES's programmatic elements involves industrial collaboration and technology transfer. Industrial collaboration with CPES takes several forms: (1) participation in the technology development and demonstration program, either as a testbed partner or working on a specific area of research interest; (2) participation in the Industrial Partners Program, where industry representatives provide guidance in the direction and implementation of CPES initiatives; and (3) involvement in the education and outreach program, either as the recipient of CPES courses and seminars or as the sponsor of student-related work.

Meaningful technology transfer is an element critical to the success of CPES in achieving its vision. Those organizations holding principal memberships in the Industrial Partners Program have access to CPES-generated intellectual properties. They also have the exclusive option to negotiate royalty-bearing licenses for commercial use.

The education and outreach program demonstrates several unique initiatives. Curriculum integration among the five campuses is taking place through distance access, providing students with a comprehensive background in power electronics. An option in power electronics for undergraduate electrical engineers at Virginia Tech and RPI has been established. This option is offered at a limited number of universities throughout the United States. Students are gaining invaluable educational experience through internships and fellowships sponsored by industry, allowing them to link theory to practice.

Peter Barbosa (G) works on a high-frequency DC/DC PWM resonant converter for applications that require high power density, low weight and volume. The
power converter has been designed to operate at 1MHZ, using the latest developments in resonant topologies and planar magnetics.


The Center for Microelectronics, Optoelectronics, and Nanotechnology
(MicrON Group)

Associated ECE Faculty
Robert Hendricks, Director
James Armstrong
Peter Athanas
Richard O. Claus
Stephane Evoy
Louis Guido
Dong Ha
Alex Huang
G.Q. Lu
Kent Murphy
Sanjay Raman
Sedki Riad
Roger Stolen
Joseph Tront
Anbo Wang

This newly formed center is a collaborative partnership among the ECE, MSE and physics departments, with support from several other departments. MicrON has been established in response to the statewide initiative to develop and enhance education and research in

The center provides unique facilities, instruments, and processing tools that are either prohibitively expensive and/or must be operated in a specialized cleanroom environment in support of the research programs of numerous research groups and centers with interests and activities in the area of microelectronics, optoelectronics, and nanotechnology, and to coordinate and develop an interdisciplinary undergraduate and graduate educational program among the participating departments.

The center operates a number of advanced research laboratories, including a Device Fabrication Laboratory, a Materials Synthesis Laboratory, and a Device and Materials Characterization Laboratory. The laboratories provide opportunities for faculty members from several departments to teach and collaborate on microelectronics research. Areas of investigation include microelectronic materials, such as wide-bandgap materials and electronic ceramics; novel devices, including power devices, high-frequency/high-speed devices; optoelectronics; MEMS; and organic light-emitting devices. Additional investigation areas involve process technologies, such as nanotechnology, advanced lithography, plasma-aided processing, and micromachining; and circuits, systems, and design work.

The center's teaching mission includes coordinating the university's undergraduate microelectronic concentration, and working with industry to create co-op experiences for both undergraduate and graduate students. The center operates two teaching laboratories: an 1800 square-foot Semiconductor Fabrication Laboratory and a Semiconductor Packaging Laboratory.

Wireless Microsystems Laboratory
Sanjay Raman, Director


A photograph of a 5-6 GHz RF x2 subharmonic mixer IC fabricated in IBM Silicon Germanium (SiGe) technology. The chip is packaged on a low-profile MLF package. The die size is 0.9mm x 0.7mm. The package size is 4mm x 4mm. This chip was designed, laid out and fully tested by Dan Johnson, a Bradley Fellow. The work was sponsored by RF Microdevices, Greensboro, NC .


The growth in the wireless communications industry reflects the tremendous demand for commercial wireless (untethered) communications services such as paging, analog and digital cellular telephony, and emerging Personal Communications Services (PCS).

Beyond the arena of mobile communications, there are numerous wireless applications including RF identification (RFID), satellite communications, Local Multipoint Distribution Systems (LMDS), and Wireless Local Area Networks (WLANs) operating at frequencies extending into the millimeter-wave regime (>30 GHz). This rapid expansion of untethered communications services, along with the need for low-cost, high-efficiency system implementations, has led to an explosion in the development of integrated circuit approaches in the RF/microwave area. These Radio Frequency Integrated Circuits (RFICs) and Monolithic Microwave Integrated Circuits (MMICs) are generally packaged together with VLSI digital signal processing (DSP) and microprocessor (mP) control chips on printed circuit boards (PCBs) or in advanced multichip modules (MCMs). However, on the immediate horizon are mixed-signal integrated circuits in which RF, low-frequency analog, and digital functions are integrated on the same chip, thus setting the stage for single-chip "VLSI" radios.

In addition, a second revolution in microelectronics is currently under way, defined by the integration of micro-mechanical structures, multifunctional materials, and micro-/opto-electronic circuits on the same semiconductor substrate - so-called integrated microsystems. These microsystems may contain mechanical actuators, micro-pumps and valves, physical and chemical sensors, optical-devices, etc. monolithically integrated with transistor-based electronics. The future potential of this technology is microchips "that can sense, think, act, and communicate." The potential impact of integrated microsystems over the next several decades could be as profound as that of conventional integrated circuits over the last several decades. One example of an integrated microsystem is a miniature implantable device that combines sensors, actuators, and computational algorithms and microcircuits for biomedical applications ranging from drug delivery to microsurgery.

The focus of the Wireless Microsystems Technology Laboratory at Virginia Tech is twofold. On the one hand, we are exploring ideas and technologies that enable integrated microsystems, in particular microsystems that are connected to the information infrastructure via wireless communications links (wireless microsystems). Secondly, the laboratory is developing ideas and technologies that enable true single-chip radios (microsystems for wireless). Consider embedded or wearable computing devices incorporating transmitters, receivers, antennas, and sensors, linked together in a distributed wireless network with high bandwidth and high information transfer capabilities. Given this context, topics of interest include, but are not limited to: Radio Frequency Integrated Circuits (RFICs); Monolithic Microwave/Millimeter-wave Integrated Circuits (MMICs); integrated antennas; mixed-signal ICs; high-speed interconnects and packaging; micromachining and Microelectromechanical Systems (MEMS); RF MEMS and MEMS sensors; distributed wireless microsensors; and mixed-technology/integrated microsystems. Specific projects currently ongoing include a mm-wave MMIC subharmonic downconverters, monolithic filters for highly-integrated digital radios, mixed RF/digital ICs in CMOS technology, SiGe front-end RFICs photo above, and integrated electrically-small antennas for wireless microsystems.


Representative Electronics Projects

Simulation of Double Gate MOS Turn-Off Thyristor
Development of Emitter-Controlled Thyristors for Power Electronics Building Block
High Power System Level Demonstration of the Emitter Turn-Off Thyristor
Acquisition of Test Equipment for the Development of Very High Power, Optical fiber Coupled Emitter Turn-Off Thyristors (ETO)
Simulation of High Voltage MOS Turnoff Thyristor
Metal Matrix Composite Base Plates for High Power Density PEBB Modules
Control and Optimization of Regenerative Power Flow in 21st Century Airlifters
NSF Engineering Research Center (CPES)
Investigation of Power Management Issues for the Next Generation Processors
Packaging of Power Electronics Building Blocks
AASERT: Optical Fiber Interconnects and Sensors for Power Electronics Building Blocks
Power Electronics Building block and System Integration
Soft-Switching Inverters for AC Speed Drives
Integration of High Speed AC Induction Motor-Inverter System for Fuel-Cell Powered Electric Vehicle Auxiliary Motor Drives
Power Amplifier Linearization for X/K-Band MMIC Applications
Integrated Antennas and Circuits for Mixed-Technology Single-Chip Systems
A Vector Network Analyzer with Millimeter-Wave Capabilities



The Bradley Department
of Electrical and Computer Engineering
Virginia Tech

Last Updated, July 15, 2001
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