High threshold voltage p-GaN gate power devices on 200 mm Si

Abstract

In this paper, we present high threshold voltage, low on-resistance, and high speed GaN-HEMT devices using a p-GaN layer in the gate stack. There are three novel features - first, for the first time, p-GaN gate HEMTs were fabricated on a 200-mm GaN on Si substrate using a Au-free fully CMOS-compatible process. Second, good electrical characteristics, including a threshold voltage of higher than 2.8 V, a low gate leakage current, no hysteresis, and fast switching, were obtained by employing a p-GaN and W gate stack. Finally, TO-220 packaged p-GaN gate HEMT devices, which can sustain a gate bias of up to 20 V, were demonstrated. Such properties indicate that our p-GaN HEMT devices are compatible with the conventional gate drivers for Si power devices.