p-GaN栅极HEMTs的同步光电驱动

We demonstrate a synchronized photonic- electronic driving (SPED) scheme for normally-off p-GaN gate HEMTs with semi-transparent gate electrodes. With an ultraviolet light-emitting diode synchronously driven with the device’s gate terminal, the HEMT has its conduction current simultaneously switched on/off both photonically and electronically, harnessing the benefits of both driving schemes and overcoming their shortcomings. At on-state, thanks to the photo-electrically enhanced conductivity, the gate overdrive voltage for the same on-current can be lowered by ~3 V compared to the electronic-only driving scheme, delivering the same on-resistance. At off-state, the electronic gate in the SPED scheme can quickly remove the photo-induced carriers from the gate stack and turn off the 2DEG channel, so that the device is free from a slow photocurrent tail that typically exists in photodetectors and photonic-gate-only phototransistors. Hence, the persistent photoconductivity in the device is suppressed, ensuring low leakage current and a stable V _ TH for E-mode operation.