[TuP3C] Power Devices

[TuP3C-04] Investigation of Gate Reliability of p-GaN Gate AlGaN/GaN MIS-HEMTs with a GaON/Al₂O₃ Gate Dielectric Stack

〇Si-Hong Chen¹, Shao-hsiang Hsu¹, Sheng-Kai Chen Chen¹, Chieh-Siang Kuo¹, Jen-Inn Chyi¹ (1. National Central University (Taiwan))

This work investigates the effects of a composite dielectric gate stack, GaON/Al₂O₃, on the performance and reliability of normally-off high power p-GaN metal-insulator-semiconductor HEMTs. The GaON interfacial layer, combined with a high-κ Al₂O₃ dielectric, significantly improves interface quality by reducing the interface trap density to as low as 1.28×10¹² cm^-2·eV^-1. The device exhibits excellent DC characteristics, including ultra-low gate leakage (10^-9 mA/mm) and low on-resistance (~1.99 mΩ·cm²). Dynamic measurements demonstrate reduced gate and drain lag effects, indicating effective suppression of both the shallow and deep traps. In TDDB analysis, the composite structure enables robust oxide reliability, supporting over 10 years of lifetime under 12 V bias stress. These results suggest that the GaON/Al₂O₃ gate stack is a promising solution for E-mode GaN-based power devices.