Heteroepitaxial α-Ga2O3 MOSFETs with a 2.3 kV breakdown voltage grown by halide vapor-phase epitaxy

Here, we report on heteroepitaxial α-Ga2O3 MOSFETs with a breakdown voltage (BV) of 2.3 kV at a specific on-resistance of 335 mΩ cm2. High-quality α-Ga2O3 layers were grown on a sapphire substrate via halide vapor-phase epitaxy (HVPE). A stack of Ti/Al/Ni/Au was used for the S/D electrode, exhibiting significantly reduced contact resistance as compared with a conventional Ti/Au stack. Consequently, the record BV and mobility of 20.4 cm2 V−1 s−1 were achieved. Moreover, a consistent critical field of 1 MV cm−1 was obtained for variable LGD. Our results are superior to recently reported heteroepitaxial α-/β-Ga2O3 MOSFETs, which is promising toward HVPE α-Ga2O3 based power devices.