Enhanced gain characteristics of AlGaN/GaN MOS-HEMTs with Al2O3 gate dielectric

We report on small-signal gain characteristics of AlGaN/GaN metal-oxide-semiconductor (MOS) high-electron-mobility transistors (HEMTs) with Al
2
O
3
gate dielectric deposited by ALD method. The fabricated MOS device exhibited both improved Mason’s unilateral gain and optimized linear gain as compared to those of the Schottky-gate HEMT. Possible origin for the improved gain for the MOS-HEMTs is discussed.