High synergy atomic layer etching of AlGaN/GaN with HBr and Ar

Here, we show a process of AlGaN/GaN atomic layer etching with a high synergy of > 91%. Achieved by means of a cyclical HBr and Ar process, highly controllable layer removal was observed within the atomic layer etching window and is attributed to careful parameter calibration plus lower reactivity of the HBr chemistry. Such etching is a valuable component in the production of high-performance enhancement-mode GaN field effect transistor devices. Published under an exclusive license by the AVS.