Photoconductive UV Detectors Based on ZnO Films Prepared by Sol-Gel Method

摘要

Highly c-axis oriented ZnO thin films were deposited on single crystal Si(111)substrates by sol-gel method.The photoconductive UV detectors based on ZnO thin films,being a metal-semiconductor-metal(MSM)structure with interdigital(IDT)configuration,were fabricated by using Au as contact metal.The characteristics of dark and photocurrent of the UV detector,the UV photoresponse of the detector were investigated.The linear current-voltage(I-V)characteristics under both forward and reverse bias exhibit ohmic metal-semiconductor contacts.Under illumination using monochromatic light with a wavelength of 365 nm,photo-generated current arrived at 44.89 muA at a bias of 6 V.The detector exhibits an evident wide-range spectral responsivity and shows a trend similar to that in photoluminescence(PL)spectrum.PL spectrum of detector exhibits two peaks,one is the near band edge emission,and another is the deep-level emission in the visible region.