Design of a 6 kV Beta-Ga2O3 PN Heterojunction Diode with Etched Double-Layered NiO with a Figure of Merit of 10 GW cm−2

Abstract

This study proposes a NiO/β-Ga2O3 etched heterojunction extension termination design for NiO/β-Ga2O3 PN diode to fulfill the application of 6 kV high-voltage with a considerably outstanding power figure of merit 10 GW cm−2, validated and optimized by sentaurus TCAD software. The results indicated the optimum termination parameters L = 20 μm and DJET = 2.3 × 1013cm−2 for the single junction termination extension structure with 4000 V breakdown voltage, and L1 = L2 = 20 μm, DJET1 = 4 × 1013cm−2 and DJET2 = 2.3 × 1013 cm−2 for the double junction termination extension structure with 6000 V. Moreover, to evaluate the power figure of merit of the optimized devices, the specific resistances were extracted from the forward characterizations with setting appropriate electron and hole mobility from experiment results, which exhibited a power figure of merit of 4.7 GW cm−2 for the single junction termination extension and 10 GW cm−2 for double junction termination extension. Meanwhile, utilizing the Poisson equation calculated the ideal one-dimension electric field at NiO/Ga2O3 interface in Ga2O3 for the optimized devices, the single junction termination extension with 5.3 MV cm−1 at reverse 4000 V, and 7.3 MV cm−1 of the double junction termination extension incredibly approached Ga2O3 critical breakdown electric field of 8 MV cm−1 at reverse 6000 V, demonstrating our designed device structures possess immense potential for high-voltage power application.