Department Seminar with Matthew Spencer: A Review of Low-Power Micromechanical Computing

Title: A Review of Low-Power Micromechanical Computing

Abstract: There are optimal conditions to operate CMOS logic that balance leakage and dynamic power, which gives rise to a minimum energy per operation for CMOS logic designs.  This energy per operation floor threatens the continuous improvement of on-die performance, and has inspired many techniques to sidestep the floor, including exotic sub-threshold switches.  Gap closing micromechanical (MEM) devices, referred to as MEM relays, presented themselves as one such switch because they display very high on/off current ratios (10^9) under small Voltage swings (as low as 100mV). However, MEM relays face an array of circuit design, process and integration challenges before they are suitable for digital logic.  This talk will review the recent history of micromechanical computing proposals, discuss process challenges that stymied initial efforts, and share some of the surprising new devices MEM relays have spawned.  In doing so, the talk will highlight recent research work that has been carried out by undergraduates at Harvey Mudd College, which has shed light on one MEM relay integration challenge, and other undergraduate-led research efforts focused on improving undergraduate education.

Bio: Matthew Spencer [he/him] is an Associate Professor of Engineering at Harvey Mudd College where he teaches about electrical engineering, directs Harvey Mudd’s Makerspace, and works part-time for Blue Cheetah Analog Design on high-speed link design. Matthew is an Iowa native, and he grew up in Ames. He received his undergraduate and masters degrees at MIT, and his PhD at UC Berkeley. His research interests include micro-electromechanical systems, circuit design, and teaching and learning in laboratories.  His engineering education research has won multiple best-in-division paper awards at the American Society of Engineering Education annual conference, particularly for his work redesigning large laboratory classes at Harvey Mudd. He was a past winner of the Outstanding Technology Directions paper from the International Solid State Circuits Conference and an Intel Research Fellowship for his work on micromechanical switches for low-power computing.