Spring Quarter 1999

ME/IE 8773-8774

MICROSCALE THERMOPHYSICAL ENGINEERING: EXPLORING A NEW FRONTIER

by

Arun Majumdar, Ph.D.
Associate Professor
Department of Mechanical Engineering
University of California, Berkeley
Berkeley, CA 94720-1740

Wednesday, May 26 1999
1:25 - 2:15 p.m.
Room 102 ME
Broadcast on UNITE Channel B
Coffee will be available in 152 ME following the seminar

Recent years have witnessed increasing interest in understanding and controlling energy conversion and transport at microscopic length, time, and energy scales. The interest is driven not only by scientific reasons but also technological ones. New experimental techniques that push the limits of measurement have shown that the mechanisms of energy conversion/transport can often be quite different at these small scales. The concurrent progress in microfabrication is providing the means to develop new technology based on microscale thermophysical phenomena. This talk will provide an outlook of this field by describing three areas of on-going research (using a few examples), namely: (i) thermophysical phenomena at sub-micrometer length scales (scanning thermal microscopy) and picosecond time scales (high-frequency thermoacoustics); (ii) nanostructured materials for controlling energy transport (phonon transport in superlattices); (iii) microdevices that exploit thermophysical phenomena and yield enhanced performance or new functionality (thermomechanical radiation, chemical, and biological sensors; thermoelectric refrigeration).

Professor Arun Majumdar completed his PhD in Mechanical Engineering from U.C. Berkeley in 1989, after which he joined the faculty of Arizona State University. He moved to U. C. Santa Barbara in 1992 and then finally returned to U.C. Berkeley as a faculty in Jan., 1997. He is a recipient of the NSF Young Investigator Award, the ASME Melville Medal, the best paper award from the ASME Heat Transfer Division. He has worked in several research areas including microscale thermophysics of solid state devices, scanning probe microscopy, micromechanical sensors and devices, tribology, and the chemistry of gas-solid and liquid-solid interfaces. He has developed the technology of scanning thermal microscopy by which it is now possible to study the thermal behavior of devices and nanostructures with sub-micrometer spatial resolution. He and his coworkers were the first to demonstrate high-resolution lithography using the atomic force microscope, which is now being further developed for large-scale nanolithography. In collaboration with Raytheon, his group has also developed the first thermo-opto-mechanical infrared camera. Recently, he and his coworkers discovered of a new phenomenon in surface science that involves the generation of a chemicurrent during chemisorption. Based on the research of his and other groups, Prof. Majumdar has developed a graduate level course in Microscale Thermal Engineering at U.C. Berkeley and has also coedited a book on this topic. He is the editor of Microscale Thermophysical Engineering and an associate editor of the Int. J. Heat & Mass Transfer and the ASME J. Heat Transfer. He has been largely responsible for starting the annual Microtherm Workshops as well as US-Japan seminars on microscale transport phenomena held every three years.

Informal Faculty Luncheon: Wednesday, May 26, 1999, 11:45 am, Room 404, Campus Club. Prof. Arun Ajumdar will be able to attend.