ORDERED ZNO NANOROD ARRAYS FOR ULTRAVIOLET DETECTION

摘要

Well-aligned ZnO nanorod arrays were grown on the Si substrate via a hydrothermal method. Excited by a 325 nm laser, the ZnO nanorods radiate a focused beam of ultraviolet light. We briefly discuss the mechanisms for emissions in the photoluminescence spectrum. A simple and low-cost method was used to fabricate the metal-semiconductor-metal photodetector based on ZnO nanorod arrays. The currentvoltage curve of the device shows double Schottky diode characteristics in the dark, and it transforms to Ohmic under ultraviolet illumination. The photogenerated current under 365 nm ultraviolet illumination is almost 25 times higher than that under 254 nm ultraviolet illumination, which is due to the easier recombination of electron-hole pairs under 254-nm ultraviolet light. The results in this paper provide a possible way to facilitate the fabrication process of nanodevices and shed light on the detection for ultraviolet of different wavelengths.