Deep Cryogenic Characterization of GaN HEMT at 4K

Cryogenic electronics has been attracting many researchers involved in space exploration, planetary study, quantum computation, and, more recently, high-efficiency cryogenically cooled aircraft. Cryogenic power system is becoming more prevalent due to the paradigm shift in the avionics industry toward fully electric and fossil-fuel-free propulsion systems. Cryogenic operation of components offers more efficient performance and cost benefits as compared to the ‘warm-box’ solution for electrical circuitry practiced over the years. As a part of the Center for High-Efficiency Electrical Technologies for Aircraft (CHEETA) program, this paper investigates the efficient and reliable performance of an off-the-shelf 650 V GaN High Electron Mobility Transistor (HEMT) down to deep cryogenic temperatures as low as -269.15 °C or 4K. The results show improved on-resistance, higher transconductance, lower threshold voltage, lower drain, and gate leakage. No carrier “freeze-out” effect has been observed in any quadrant, which makes it an ideal candidate for cryogenic power electronics for aircraft and space applications. These results will allow the researchers to harness the full potential of GaN devices in aircraft and space applications and design electronics for harsh environments.