Stable enhancement-mode operation in GaN transistor based on LiNiO junction tri-gate

In this work, we demonstrate p-type lithium nickel oxide (LiNiO) as a heterojunction gate combined with tri-gate structures to achieve stable enhancement-mode (e-mode) AlGaN/GaN high-electron-mobility transistors. The low deposition temperature (400 °C) and high-quality LiNiO coated by pulsed-laser-deposition over tri-gate structures resulted in enhancement-mode devices without the need for special epitaxial layers, barrier recess, or barrier regrowth. The LiNiO heterojunction tri-gate devices presented a positive VTH of 0.7 V (at 1 μA/mm), a low on-resistance of 8 Ω· mm, a large maximum on-current of 390 mA/mm, a high breakdown voltage of 1270 V, and excellent reliability simultaneously.