Modulating the threshold voltage of oxide nanowire field-effect transistors by a Ga^＋ ion beam

In this paper, we report a method to change the threshold voltage of SnO2 and In2O3 nanowire transistors by Ga^＋ ion irradiation. Unlike the results in earlier reports, the threshold voltages of SnO2 and In2O3 nanowire field-effect transistors （FETs） shift in the negative gate voltage direction after Ga^＋ ion irradiation. Smaller threshold voltages, achieved by Ga^＋ ion irradiation, are required for high-performance and low-voltage operation. The threshold voltage shift can be attributed to the degradation of surface defects caused by Ga＋ ion irradiation. After irradiation, the current on/off ratio declines slightly, but is still close to -106. The results indicate that Ga^＋ ion beam irradiation plays a vital role in improving the performance of oxide nanowire FETs.