SiO2/AlGaN/GaN MOSHFET with 0.7 µm gate-length and fmax/fT of 40/24 GHz
The performance of SiO2/AlGaN/GaN MOSHFETs is described. The C–V measurements showed slight increase in sheet carrier density after applying 12 nm-thick PECVD SiO2. The devices exhibited gate leakage current of 5×10−10 A/mm. Small-signal RF characterisation of 0.7 µm gate length devices yielded an fT of 24 GHz and an fmax of 40 GHz, which are comparable to those typical for state-of-the-art AlGaN/GaN HFETs.