ZnO thin films were grown by pulsed laser deposition (PLD) at different substrate temperature ranging from 200 to 700 degrees C. X-ray diffraction (XRD), atomic force microscope (AFM), photoluminescence (PL) and Raman spectroscopy are applied to investigate the change of properties. The results suggest that Raman scattering is the more effective technique to reveal the crystal quality of ZnO thin films compared with XRD and PL spectrum. The intensity of the UV emission peaks and XRD spectrum suggest no much dependence on the crystal quality. The higher temperature of the substrate, the easier of the defects will be formed during the deposition, and optimum temperature is 400 degrees C in this letter. (c) 2007 Elsevier B.V. All rights reserved.