Enhancement-mode GaN HEMT utilizing ZAZ-structured multi-stack charge-trap layers

Abstract

In this study, we investigate the performance of GaN high electron mobility transistors (HEMT) enhanced with multilayer charge trap layers (CTL) featuring the ZrO₂/Al2O3/ZrO₂/Al₂O₃/ZrO₂ (ZAZ) structure. The ZAZ structure forming a multiple quantum well configuration effectively addresses the limitations of conventional CTL, such as poor retention and low distribution. Experimental results show that the ZAZ structure exhibits efficient programmability for the same power, excellent dispersion characteristics, and superior charge retention, which is reduced by 22 % compared to 45.5 % observed in the reference device. These results demonstrate that the ZAZ CTL is a promising solution for enhanced GaN HEMT, advancing their applications in high-efficiency, high-power electronic systems.