• Journal of Korean Ophthalmic Optics Society
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• v.10 no.3
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• pp.193-203
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• 2005

Highly c-axis oriented nanocrystalline ZnO thin films on silica glass substrates were prepared by spin coating-pyrolysis process with a zinc naphthenate precursor. Only the XRD intensity peak of (002) phase was observed for all samples. With an increase in heat treatment temperature, the peak intensity of (002) phase increases. No significant aggregation of particle was present. From scanning probe microscopy analyses, three-dimensional grain growth, which was thought to be due to inhomogeneous substrate surface and c-axis oriented grain growth of the ZnO phase, was independent on heal-treatment temperature. Highly homogeneous surface of the highly-oriented ZnO film was observed at $800^{\circ}C$. All the films exhibited a high transmittance (above 80%) in visible region except film heat treated at $1000^{\circ}C$, and showed a sharp fundamental absorption edge at about $0.38{\sim}0.40{\mu}m$. The estimated energy band gap for all the films were within the range previously reported for films and single crystal. ZnO films, consisting of densely packed grains with smooth surface morphology were obtained by heat treatment at $600^{\circ}C{\sim}800^{\circ}C$, expected to be ideal for practical application, such as transparent conductive film and optical device.