5.3A/400V normally-off AlGaN/GaN-on-Si MOS-HEMT with high threshold voltage and large gate swing

Normally-off AlGaN/GaN metal-oxide-semiconductor high electron mobility transistors (MOS-HEMTs) on Si substrate were fabricated with the fluorine-based treatment technique. By employing a 20nm-thick Al2O3 gate dielectric deposited by atomic layer deposition, the fabricated MOS-HEMT exhibits a large positive threshold voltage of +3.5V, a maximum gate input voltage of 15V, a maximum saturate drain current of 5.3A and an off-state breakdown voltage of 402V. The high threshold voltage and the large input voltage swing is expected to improve the electromagnetic interference immunity and safety of AlGaN/GaN MOS-HEMT power switches.