[MoC4] GaN HEMTs for Power (I)

4:45 PM - 5:00 PM JST(7:45 AM - 8:00 AM UTC)

[MoC4-02] Low-Defect Lithium-Doped NiO_x Gate via Ultrasonic Spray Pyrolysis Deposition for Robust 1.9 kV Normally-off InAlGaN/GaN HEMTs

〇Yu-Hsuan Chen¹, Yan-Kuei Wu¹, Wei-Chou Hsu¹ (1. National Cheng Kung Univ. (Taiwan))

This work demonstrates a high-performance enhancement-mode (E-mode) GaN high-electron-mobility transistor (HEMT) featuring a lithium-doped nickel oxide (p-Li:NiO) gate stack. The gate is formed by ultrasonic spray pyrolysis deposition (USPD), a low-temperature, non-vacuum process enabling uniform dopant incorporation and high-quality p-type oxide films. The resulting gate exhibits superior electrostatic control and favorable switching behavior. Integrated with a stepped-gate field-plate (SGFP) architecture, the device achieves a positive threshold voltage (V_TH) of 0.736 V and a high Baliga figure of merit (BFOM) of 3.85 GW/cm², balancing breakdown voltage and on-resistance. Additionally, stable current performance with only 3.6% variation under 10,000 s constant-bias stress confirms the reliability of the proposed gate design. Based on these findings, this work proposes USPD-grown p-Li:NiO as a promising gate technology for normally-off, high-power GaN applications.