A 1200-V GaN/SiC cascode device with E-mode p-GaN gate HEMT and D-mode SiC junction field-effect transistor

摘要

A 1200-V/100-m Omega GaN/SiC cascode device is demonstrated with small capacitances for fast switching speed, no dynamic ON-resistance (R-ON) degradation, and stable high-temperature threshold voltage (V-TH). To identify its safe operation in the OFF-state with a high drain bias, the middle point voltage (V-M) between the GaN and SiC devices is investigated under static and dynamic modes. An adequately low V-M is achieved at both static and dynamic states. A voltage distribution process found that the OFF-state V-M is capacitance-dependent during the turn-off transient and turns to be resistance-dependent to match the leakage current with a steady drain bias. (C) 2019 The Japan Society of Applied Physics