Single β-Ga₂O₃nanowire back-gate field-effect transistor

In this work, a normally-on single-monocrystal β-Ga2O3 nanowire (NW) back-gate field-effect transistor (FET) has been demonstrated by transferring metal-organic chemical vapor deposition-grown β-Ga2O3 NWs on sapphire onto SiO2(300 nm)/p +-Si substrate. When the gate voltage (V G) exceeds -14 V, the device is pinched off, with an on/off ratio greater than 108 and a drain leakage current density as low as 1/47.34 fA. The maximum field-effect carrier mobility for these n-doped single β-Ga2O3 NW FETs reaches 1/462.2 cm2 (V s)-1. A prompt degradation in the on/off ratio for these β-Ga2O3 NW back-gate FETs is observed as the operation temperature increased up to 400 K. With strong evidence, the temperature-dependent degradation in the performance is determined by the activation of self-trapped holes and intrinsic vacancy-related defects, both of which would lead to a rapid increase in the channel leakage current at high temperatures.