Seminars

ME/IE 8773-8774
DESIGN AND MANUFACTURING SERIES (1130 ME)
Topic: Micro Electro Mechanical Systems (MEMS)
Host: Tianhong Cui

MEMS Enabled Microfluidics - Microvalves And Miniature Gas
Chromatography Systems On-A-Chip

by

Peter J. Hesketh, Professor
George W. Woodruff School of Mechanical Engineering
Georgia Institute of Technology, Atlanta, GA 30332-0405

Wednesday, March 23, 2005
3:30-5:00 p.m.
Room 1130 ME
Coffee and cookies will be available at 3:15 p.m. in Room 1130 ME before the seminar

Abstract: — Microvalves are essential components in the miniaturization of fluidic systems. Microvalves control fluid flow in a variety of applications as diverse as chemical analysis systems, micro-fuel cells, and integrated fluidic channel arrangements for electronic cooling. Using microvalves, these systems offer important advantages: they can operate using small sample volumes and provide rapid response time. Electromagnetically actuated microvalves have been fabricated on a single wafer with a potentially CMOS compatible process. The design, fabrication, and testing results of two different types of microvalves are presented: the on/off microvalve and the bistable microvalve with latching mechanism. The microvalves operate with a power consumption of less than 1.5 W and can control the volume flow rate of DI water, or of a 50% diluted methanol solution in the range 1 – 50 µL/min. The leaking rate of the on/off microvalve is on the order of 30 nL/min. The microvalves demonstrate a response time for latching of 10 ms in water and 0.2 ms in air. One of the most powerful and versatile analytical tools is gas chromatography. Miniaturization of gas chromatography (GC) is required for the realization of a very important application: portable chemical analysis systems. A vital element in the development of a hand-held GC system is the separation column. The development of such a miniature separation column has been achieved. It has a low thermal mass and an embedded heating element for rapid thermal cycling.
These and related subjects are presented:

Bio: Peter Hesketh was born in Liverpool, England, and graduated with a B.Sc. in Electrical and Electronic Engineering from the University of Leeds, in 1979. He worked at the B.B.C. Engineering Research Department in Kingswood, Surrey, developing novel electronic circuits for broadcast applications. He was a Thouron Fellow at the University of Pennsylvania obtaining an M.S. (1983) and Ph.D. (1987) in Electrical Engineering. He worked in the Microsensor Group at the Physical Electronics Laboratory of Stanford Research Institute and then Teknekron Sensor Development Corporation before joining the faculty at the University of Illinois in 1990 in the Department of Electrical Engineering and Computer Science. He was Co-director of the Microfabrication Applications Laboratory from 1995-1998 and Director of the Microfluidics Center 1996-1998. He is now a Professor of Mechanical Engineering at Georgia Institute of Technology and Director of the MEMS Group in the School of Mechanical Engineering. He is past chairman of the Sensor Division of the Electrochemical Society and a Fellow of the American Association for the Advancement of Science. His research interests are in microfabrication of sensors and microfluidic systems. He has published over forty five papers and edited eight books on microsensor systems. He is a member of the AAAS, ASME, AVS, ECS and IEEE.

Informal Faculty Luncheon: Wednesday, March 23, 2005, 12:00 noon. Meet in 1100 ME and walk to lunch with other faculty. Prof. Peter Hesketh will be able to attend.