Combination of selective area sublimation of p-GaN and regrowth of AlGaN for the co-integration of enhancement mode and depletion mode high electron mobility transistors

We report on the fabrication of an enhancement mode p-GaN/AlN/GaN high electron mobility transistor with selective area sublimation under vacuum of the p-GaN cap layer. The GaN evaporation selectivity is demonstrated on the thin 2 nm AlN barrier layer. Furthermore, the regrowth of AlGaN is a major key to increase the maximum drain current in the transistors and enables the co-integration with depletion mode devices.