Quaternary In 0.05 Al 0.70 Ga 0.25 N/GaN HEMTs With On-Resistance of $0.97\ \Omega\cdot \text{mm}$

A quaternary InAlGaN Schottky barrier layer is used for low resistive two-dimensional electron gas channel, induced by high electron density and mobility. The fabricated 200-nm-gate In 0.05 Al 0.70 Ga 0.2 N/GaN HEMTs device shows an on-resistance of $0.97\ \Omega\cdot \mathbf{mm}$ , a maximum drain current density of 2.12 A/mm, and a maximum transconductance of 570 mS/mm.