Toward stable gate-controlled GaSb nanowires near-infrared photodetection and photocommunication

Surface states originating from the dangling bonds or native oxide layers are challenging III-V group semiconductor nanowires (NWs) in future electronics and optoelectronics. In this work, a plasma surface treatment technique is adopted for effectively modulating the surface states of GaSb NWs, benefiting the bias-stress stability of field-effect-transistors (FETs) and gate-controlled near-infrared (NIR) photodetectors. With an optimal treatment power of 50 W, the as-fabricated GaSb NWFET shows a drain current reduction less than 15% under 60 min gate bias, which shows a significant improvement upon the pristine NWFET. Under the illumination of a 1550 nm laser, the light current, dark current, responsivity, and photoconduction gain of bias-stress stability NWFETs exhibit distinct gate-voltage-dependent modulation characteristics. All results benefit from the effective removal of the oxide layer and effective formation of the passivation layer by the plasma surface treatment. In the end, the bias-stress stability NWFET demonstrates significant promise in the gate-controlled NIR imaging and photocommunication.