COMPARISON OF THE HYDROTHERMAL AND VPT GROWN ZnO NANOWIRE FIELD EFFECT TRANSISTORS

Abstract

ZnO nanowires (NWs), grown by hydrothermal and vapor phase transport (VPT) methods, were employed as the channel layers to fabricate single nanowire Field Effect Transistors (NWFETs) with a p+-silicon as the bottom gate. The FET employing hydrothermal grown ZnO NWs shows n-type depletion mode with a field mobility of 18.27 cm2/V⋅s, an on/off ratio of 106, and a threshold voltage of -48.5 V. In comparison, the device using VPT grown NWs operates in n-type depletion mode with a field effect mobility of 36.94 cm2/V⋅s, a drain current on/off ratio of 105, and a threshold voltage of -14 V. The reason for the difference of threshold voltage and the mobility by two methods was discussed in this paper.