Demonstration of etching-trench-assisted deep implantation PIN junction termination Ga2O3 SBD with 6.6 kV breakdown voltage and 10.69 GW/cm2 power figure of merit

β-Ga2O3 is an ultra-wide bandgap semiconductor highly attractive for next-generation high-voltage power electronics, but its device development is hindered by the lack of effective p-type doping. Here, we report a vertical β-Ga2O3 Schottky barrier diode with a p-i-n junction composite termination integrated with a high-resistivity implanted region. A double-layer p-Cr2O3 structure is employed on the mesa sidewall, and ion implantation assisted by the mesa slope is used to form a high-resistivity implanted region to suppress reverse leakage and optimize electric field distribution. The optimized device exhibits a breakdown voltage of 6.6 kV, a specific on-resistance of 4.1 mΩ cm2, and a power figure of merit of 10.69 GW/cm2, together with low turn-on voltage and good stress reliability. This composite termination structure effectively suppresses leakage and enhances voltage capability, providing a promising route for high-performance β-Ga2O3 power devices.