Simple fabrication of a ZnO nanowire photodetector with a fast photoresponse time

A zinc oxide (ZnO) nanowire photodetector was fabricated by a simple method of growing ZnO nanowires bridging the gap of two patterned zinc electrodes. The nanowire growth is self-catalytic, involving the direct heating of patterned Zn electrodes at 700 degrees C in an O-2/Ar gas flow of 20 SCCM (standard cubic centimeter per minute at STP)/80 SCCM, respectively, at atmospheric pressure for 3 h. The fabricated photodetector demonstrated fast response of shorter than 0.4 ms to UV illumination in air, which could be attributed to the adsorption, desorption, and diffusion of water molecules in the air onto the nanowire significantly influencing the photoresponse.