Pulsed laser deposition of ZnO thin films for applications of light emission

Abstract

ZnO is a material suitable for light emission. In order to investigate the light emission properties, ZnO thin films were deposited on (0001) sapphire substrates by pulsed laser deposition (PLD) technique using an Nd:YAG laser with a wavelength of 355 nm. The influence of the deposition parameters, such as oxygen pressure, substrate temperature and laser energy density variation on the properties of the grown film, was studied. The experiment was performed for substrate temperatures in the range 200–600°C. The deposition chamber was filled with the oxygen at working pressures between 10 −6 and 5×10 −1 Torr. According to observations, the intensity of the light emission of laser-ablated ZnO thin films increased as substrate temperatures increased from 200 to 600°C. We investigated the structural, electrical and optical properties of ZnO thin films using X-ray diffraction (XRD), van der Pauw Hall measurements, photoluminescence (PL), and Rutherford backscattering spectrometry (RBS).