Abstract: ZnO thin films were grown on GaAs (001) substrates by metal-organic chemical vapor deposition (MOCVD) at low temperatures ranging from 100 to 400℃.DEZn and H2O were used as the zinc precursor and oxygen precursor,respectively.The effects of the growth temperatures on the growth characteristics and optical properties of ZnO films were investigated.The X-ray diffraction measurement (XRD) results indicated that all the thin films were grown with highly c-axis orientation.The surface morphologies and crystal properties of the films were critically dependent on the growth temperatures.Although there was no evidence of epitaxial growth,the scanning electron microscopy (SEM) image of ZnO film grown at 400℃ revealed the presence of ZnO microcrystallines with closed packed hexagon structure.The photoluminescence spectrum at room temperature showed only bright band-edge (3.33eV) emissions with little or no deep-level emission related to defects.

Key words: metal-organic chemical vapor deposition, ZnO film, GaAs, low-temperature