The National Science Foundation (NSF) has awarded Taewoo Kim, an assistant professor in the Edward E. Whitacre Jr. College of Engineering (WCOE)Department of Electrical and Computer Engineering (ECE), a $450,000 grant to study how radiation affects High-Electron-Mobility Transistors (HEMTS) made from Gallium Nitride (GaN), a wide bandgap semiconductor material.
Gallium nitride and its associated alloys have been utilized to fabricate high-voltage, high-speed, high-power, and high-frequency electronic devices. Its high thermal conductivity allows device operation at far higher power and elevated temperatures than conventional Silicon, making it well suited for electronic systems exposed to intense radiation and extreme temperatures.
Yet scientists still lack a fundamental understanding of how radiation changes charge transport and device performance in this material.
“Our goal is to move beyond empirical radiation testing and establish a predictive understanding of how radiation changes semiconductor transport physics,” Kim said. “That knowledge could help engineers design more reliable electronics with greater confidence while reducing costly, time-consuming qualification testing.”
The study will examine how radiation changes the movement of electrical charge through gallium nitride material at the atomic level.
The project, led by Kim with co-principal investigator Ravindra Joshi, chair of ECE, brings together Texas Tech University (TTU) and Los Alamos National Laboratory (LANL).
"This great collaboration will strengthen the connections between Texas Tech and the National Lab system.," adds Roland Faller, dean of the WCOE.
At LANL’s Ion Beam Materials Laboratory, accessed through the Center for Integrated Nanotechnologies user program, the team will expose HEMTs to proton radiation under controlled conditions and monitor changes in the transistors’ physical and electrical properties. Rather than relying on empirical curve fitting, the researchers will link radiation-induced defects to measurable changes in charge transport and transistor performance, creating a physics-based predictive framework for Radiation-Hardness-by-Design.
That framework is crucial to benefit national and commercial space programs—including satellite communications, defense radar systems, deep-space missions, and the high-power electronics industry—because it will reduce device qualification timelines from many months of testing to potentially a single confirmatory test.
“By connecting fundamental transport physics to device design, we aim to give industry, and government partners a practical path toward electronics that perform reliably in extreme environments,” Kim said.
Kim’s research in this field has spanned almost three decades. The project also builds on Texas Tech’s research strengths in semiconductor devices, extreme-environment electronics and radiation effects. He is excited about how this project will not only add to our ability to improve space-based communications and defense technology but also introduce undergraduate and high school students to semiconductor and space technology research.