The effect of alpha particle irradiation on electrical properties and defects of ZnO thin films prepared by sol-gel spin coating

Abstract ZnO thin films were prepared using the sol-gel spin coating technique. The structure was investigated using X-ray diffraction (XRD). The XRD spectra exhibited typical randomly orientated structure with a slight preference for growth along the (002) plane and a crystallite size of ∼ 48 nm. The Schottky barrier diodes were fabricated on the synthesized ZnO thin films. The electrical properties before and after irradiating the devices with alpha particle irradiation were characterized using current-voltage (I-V), capacitance-voltage (C-V), deep-level transient spectroscopy (DLTS) and Laplace-transform deep-level transient spectroscopy (L-DLTS) techniques. Pd/ZnO/n-Si/AuSb Schottky diodes exhibited good rectifying properties. Before irradiation, the DLTS spectra revealed one defect E 4 with activation enthalpy 0.41 eV. After irradiation, there is a new defect E α with the activation enthalpy 0.35 eV. Laplace-transform deep-level transient spectroscopy (L-DLTS) revealed the fine structure of the E α to be made up of 0.53 eV and 0.36 eV defects.