AlGaN/GaN Metal–Oxide–Semiconductor High-Electron-Mobility Transistors with a High Breakdown Voltage of 1400 V and a Complementary Metal–Oxide–Semiconductor Compatible Gold-Free Process

This paper reports the fabrication and characterization of AlGaN/GaN-on-sapphire metal–oxide–semiconductor high-electron-mobility transistors (MOS-HEMTs) using a complementary metal–oxide–semiconductor (CMOS) compatible gold-free process. Devices with a gate-to-drain spacing L GD of 20 µm achieved an off-state breakdown voltage V BR of 1400 V and an on-state resistance R on of 22 mΩ·cm 2 . This is the highest V BR achieved so far for gold-free AlGaN/GaN MOS-HEMTs. In addition, high on/off current ratio I on / I off of ∼10 9 and low gate leakage current I G of ∼10 -11 A/mm were also obtained.