| ZnO is a wide band gap semiconductor with optical transparency in the visible range. It crystallizes is a hexagonal wurtzite structure with 3.30 eV band gap and large exciton binding energy of 60meV at room temperature. ZnO is a kind of very promising materials for making the optoelectronics devices such as UV/blue light-emitting diodes and short-wavelength semiconductor diode laser devices and put in application. In recent years, the fabrication of ZnO films has attracted a considerable amount of interest due to their potential application in flat-paned displays, solar cells, gas sensors and optical waveguides.In this thesis, transparent and conductive high-preferential c-axis-oriented zinc oxide (ZnO) thin films have been prepared by sol-gel method. Zinc oxide thin films with varying thickness and different annealed temperature were fabricated and discussed in detail. The SEM micrographs and XRD patterns of the ZnO films showed that the film had a smooth surface and strongest orientation. The films have very strong absorption in the short wavelength range and the absorption edge is about 370nm.The optical transmittance spectra of the film showed a good transmittance (85%) within the visible wavelength region.Al-doped Zinc Oxide thin films were prepared by sol-gel mathod, The optical and electrical characteristics of the ZAO thin films were investigated.The results showed that: (l)The X-ray diffraction patterns show that ZAO thin films has ahexagonal wurtzite structure. (2)Photoluminescence (PL) spectra of the ZAO thin films have blue shift. (3) Raman spectrum of the ZAO thin films had changed with different Al-doped ratio. (4)The maximum conductance of 1.3×103S/cm was obtained for the thin films doped with 1% Al3+, annealed at 700 ℃.Effects of Ag,Ce and Ti doping on the microstructures and optical properties of ZnO thin film were studied. The results showed that thim film has ahexagonal wurtzite structure and transmittance of thin film had changed within 400nm600nm.
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