Performance-improved normally-off AlGaN/GaN high-electron mobility transistors with a designed p-GaN area under the recessed gate

摘要

Stable normally-off operation with high threshold voltage (V) is strongly desired in power switching applications. A p-GaN area under the barrier-recessed gate is employed to improve the V and off-state characteristics of the GaN-based HEMTs. TCAD-based device simulations are carried out to demonstrate and optimize the proposed structures. Finally, improved performances with V over 5V and breakdown voltage (BV) over 1500V are achieved in the HEMTs with combined gate p-GaN design and multiple step-shaped field plate structures.