A dual-gate and Γ-type field plate GaN base E-HEMT with high breakdown voltage on simulation investigation

Abstract

This paper proposes to insert a buried P-type gate (BPT gate) under the channel layer of the recessed MIS-high electron mobility transistor (HEMT) to form a dual-gate HEMT. And through simulation calculation, the device performance is calculated and the working mechanism of the BPT gate is explained in detail. Compared with a conventional AlGaN/AlN/GaN HEMT and a gate-recessed MIS-HEMT, the dual-gate HEMT has a higher breakdown voltage (1126 V) and a larger threshold voltage (1.5 V). The results show that inserting a BPT gate in a gate-recessed MIS-HEMT can increase the threshold voltage and improve the breakdown characteristics. Through the optimization of the device structure, it is found that the combination of the MIS-gate and the Γ-type field plate based on the dual-gate device can obtain a higher breakdown voltage. Its breakdown voltage can reach 3041 V, and the figure of merit is as high as 3.56 GW cm−2. This reveals that the combination of dual-gate and Γ-type field plate has great potential in the manufacture of enhancement-mode and high-voltage power transistors.