Annealing-induced conductivity transition in ZnO nanowires for field-effect devices

Abstract

We report on the fabrication of ZnO nanowire (NW) devices in which the NWs were annealed in air ambient for their conductivity change from conducting to semiconducting states. Ambient annealing at 600 degrees C effectively gained a good semiconducting state of ZnO NW. Either top- or bottom-gate NW field-effect transistors (FETs) with optimally annealed ZnO NW showed a high on/off current ratio of similar to 10(6), while the NW FETs with the initially conducting NWs appeared to keep on-state only. Schottky diode with the annealed NW displayed an ideality factor of similar to 1.51 along with an on/off ratio of similar to 10(3).