Schottky Source/Drain InAlN/GaN Metal–Insulator–Semiconductor High-Electron-Mobility Transistor with High Breakdown Voltage and Low On-Resistance

Abstract

In this work, we present a novel device technology of using Schottky source/drain (SSD) in InAlN/GaN metal–insulator–semiconductor high-electron-mobility transistors (MISHEMTs) for off-state breakdown voltage VBD improvement. The Schottky source/drain design can effectively prevent the source carrier injection compared to the conventional MISHEMTs, leading to enhanced VBD in the SSD MISHEMTs. A VBD of 460 V is obtained in an InAlN/GaN SSD MISHEMTs with low specific Ron of 2.27 mΩ·cm2, at a 170% VBD improvement compared to conventional MISHEMTs. Despite the Schottky source/drain used, a SSD MISHEMT with a gate length of 1 µm exhibits respectable drain current density of 416 mA/mm and transconductance of 113 mS/mm.