Solid State Seminar: Oxide Semiconductors for Power Electronics

Professor Becky Peterson
Assistant Professor, Electrical Engineering and Computer Science Department
University of Michigan

Oxide semiconductors’ unique properties – a wide bandgap, reasonably high electron mobility, and ease of bulk and thin film preparation – have facilitated their commercial success in electronics. Varistors made with polycrystalline zinc oxide dominate the market for medium-range surge arresters, while amorphous indium gallium zinc oxide has replaced amorphous silicon in the active matrix backplane of large-scale, high frame-rate displays. In this talk, I will describe my group’s recent work on amorphous and crystalline oxide semiconductors for power devices. We report a facile solution process for deposition of amorphous zinc tin oxide (ZTO) thin film semiconductors. By using inks with metal organic decomposition routes, we obtain a wide process window for future roll-to-roll, low-cost, large-scale manufacturing of flexible electronics or heterointegration with CMOS or other platforms. We then demonstrate the utility of the solution-processed ZTO semiconductor in two power electronic device architectures: (1) lateral thin film transistors with gate-drain offset and gate field plates for high voltage switches, and (2) vertical Schottky diodes for AC-DC conversion and energy harvesting circuits. The vertical diode configuration minimizes on-resistance and exploits in situ oxidation and reduction with the bottom, rectifying electrode. Finally, I will report on our recent studies of charge transport and dielectric interfaces in beta-phase crystalline gallium oxide for high voltage (~1kV) power devices.


Becky Peterson S3 speaker

Becky (R. L.) Peterson received her B.S., M.S. and Ph.D. degrees from University of Rochester, NY, University of Minnesota – Twin Cities, and Princeton University, respectively, all in electrical engineering. She was previously a post-doctoral researcher at the Cavendish Laboratory, Department of Physics, and an Associate Lecturer at Newnham College at Cambridge University, UK. Since 2013, she has been an Assistant Professor at the University of Michigan in Electrical Engineering and Computer Science. Dr. Peterson is the recipient of the University of Michigan’s 2018 Henry Russel Award, an NSF CAREER award in 2017, a DARPA Young Faculty Award in 2014 and Director’s Fellowship in 2016, an Elizabeth C. Crosby Research Award in 2013, and she is a Senior Member of IEEE. She serves on the Technical Program Committee of the IEEE/MRS Device Research Conference and on the Organizing Committee of the MRS Electronic Materials Conference. For more information about her research, please visit

Host: Professor Patrick Fay