Enhanced AlGaN-GaN high-electron-mobility transistors (HEMTs) offer significant advantages for high-reliability circuit design. This study proposes a hybrid gate structure combining a p-GaN cap with a recessed gate, utilizing a double-barrier AlGaN-Ga-AlGaN gate stack to form a double-barrier cap HEMT (DBC-HEMT). This configuration establishes dual potential barriers at the gate–AlGaN and GaN–AlGaN interfaces, while introducing an additional barrier and polarization field within the gate region to suppress gate leakage current (IGS). By optimizing the Al composition in the double-barrier cap, p-GaN layer thickness and doping concentration, and recess depth, the conduction band profile and depletion width at the interface are precisely controlled. The optimized cap achieves a threshold voltage (Vth) shift from +1.7 to +3.4 V.
Pour en savoir plus : Research on High Threshold Voltage, High Output Current and Low Gate Leakage Current p-GaN and Grooved Gate Composite Gate HEMT with N-Well and AlGaN–GaN–AlGaN Double Barrier Cap Layer
