HYDROTHERMAL SYNTHESIS of ZnO FILMS and CHARACTERIZATION

Abstract

In this study, ZnO films were produced by hydrothermal synthesis onto glass substrates. The structural properties of ZnO films were examined using X-ray diffraction (XRD) techniques. According to XRD results, the high quality polycrystalline ZnO films were achieved at low temperature. Spectroscopic ellipsometry (SE) technique and Cauchy-Urbach model were used to the important optic constants of films as the thickness (d), refractive index (n) and extinction coefficient (k). The transmittance, absorbance and reflectance spectra of films were obtained by Uv-vis spectrophotometer and optical properties were analyzed using these spectra. Also, the surface properties, roughness and electrical resistivity values were investigated by atomic force microscopy (AFM), field emission scanning electron microscopy (FESEM) and four-probe technique, respectively. Finally, the characterization results of ZnO films showed that, hydrothermal synthesis allowed production of ZnO films which higher quality than other techniques at low temperature.

Keywords

• Hydrothermal synthesis,ZnO films,XRD,Optic constants

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