High photosensitivity and low dark current of photoconductive semiconductor switch based on ZnO single nanobelt

Photoconductive semiconductor switch (PCSS) based on ZnO single nanobelt (NB) was fabricated by controlling the concentration of mixed solution and using the probe technique, and applied into a test circuit to control the circuit state. The current-voltage characteristics and voltage spectra were investigated by System source meter and oscillograph, and the results show that the PCSS is of high photosensitivity of 104, low dark current of similar to 10(-3) mu A, low power consumption of similar to 2.45 mu W, typical rise time 0.12 s, and decay time 0.15 s. Within the wavelength range of 280-340 nm, the shorter the wavelength is, the higher the voltage response is. The test circuit state conversion between 1 and 0 is obviously corresponding to UV illumination on and off. The high photosensitivity and low dark current of PCSS can be reasonably explained by using the view point of light absorption and oxygen chemisorption mechanism. (C) 2010 Elsevier Ltd. All rights reserved.