Enhancing the Performance of Field Effect Transistor Based on N-Type In₂O₃ Nanowires via Gallium Doped

In recent years, n-type In₂O₃ nanowires (NWs) have attracted tremendous attention for their excellent optical and electrical properties. Field-effect transistors (FETs) based on n-type In₂O₃ NWs have been widely applied to memory devices, solar cell, especially photodetector for UV region. However, the relatively low electron mobility of the In₂O₃ NWs grown by chemical vapor deposition (CVD) limits their further application. Here, by doping Ga, NWs with diameter down to 30nm diameter grown by chemical vapor deposition (CVD) in ambient pressure are successfully prepared. The Ga doping is found to enhance the crystal quality of In₂O₃ NWs and helps to yield thin and uniform NWs with low oxygen vacancy concentration. Comparing to the device based on pure In₂O₃ NWs grown in the same condition, the threshold voltages of field effect transistor based on 10 at% Ga doped In₂O₃ NWs shift in positive gate voltage and the corresponding carrier concentration at zero gate voltage decrease from ~1.29*10¹⁹ cm^-3 to 1.15*10¹⁹ cm^-3. Moreover, affected by the control of radial growth and reduction of oxygen vacancies that can act as ionized impurity scattering centers, FET based on single 10 at% Ga doped In₂O₃ NWs with diameter of about 30 nm with electron mobility up to ∼750 cm²V^-1s^-1 can be achieved. Meanwhile, the mobility of corresponding parallel NWs array FET is up to ∼210 cm²V^-1s^-1. All these results indicate promising potency of Ga doped In₂O₃ NWs in low-cost and large scale fabrication for high performance electronics.