Abstract
This study comprehensively investigates the influence of high-k dielectric passivation layers on the electrical stability of p-GaN gate high-electron-mobility transistors (HEMTs). Specifically, we evaluated three different passivation materials (Al 2 O 3 + SiO 2 ), (Si 3 N 4 + SiO 2 ), and (ZrO 2 + SiO 2 ) to enhance device performance in terms of breakdown voltage and dynamic stability. Experimental results indicate that ZrO 2 -based passivation significantly improves breakdown voltage and mitigates electron trapping, thereby minimizing the impact of surface defects. These findings underscore the potential of high-k passivation layers to substantially improve the reliability and performance of p-GaN gate HEMTs, especially for high-voltage and high-frequency power electronics applications.