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Zinc oxide (ZnO) thin films were deposited on (100) Si substrates by sol-gel technique. Zinc acetate was used as the precursor material. The effect of different annealing atmospheres and annealing temperatures on composition, structural and optical properties of ZnO thin films was investigated by using Fourier transform infrared spectroscopy, X-ray diffraction, atomic force microscopy and photoluminescence (PL), respectively. At an annealing temperature of 400°C in N2 for 2 h, dried gel films were propitious to undergo structural relaxation and grow ZnO grains. ZnO thin film annealed at 400°C in N2 for 2 h exhibited the optimal structure and PL property, and the grain size and the lattice constants of the film were calculated (41.6 nm, a = 3.253 A and c = 5.210 A). Moreover, a green emission around 495 nm was observed in the PL spectra owing to the oxygen vacancies located at the surface of ZnO grains. With increasing annealing temperature, both the amount of the grown ZnO and the specific surface area of the grains decrease, which jointly weaken the green emission.

Tb-doped Zinc oxide (ZnO:Tb) films were prepared by RF reactive magnetron sputtering of a Zn target with some Tb-chips attached. The results show that the appropriate Tb ions incorporated into ZnO films can improve the structural and electrical properties of ZnO films. Photoluminescence (PL) measurements show that the characteristic emission lines correspond to the intra-4fn-shell transitions in Tb3+ ions at room temperature. Under the optimal conditions, the ZnO:Tb films were prepared with the lowest resistivity (ρ) of 9.34 × 10−4Ωcm, transmittance over 80% at the visible region and the strong blue emission.

ZnO:Ni films with different doping concentrations （0—7at.%） have been deposited by radio frequency magnetron sputtering. The results of x-ray diffraction, including θ-2θ mode and rocking curve mode, indicate that the film doped with 5at.% Ni shows an excellent preferred growth along c-axis orientation. The （002） diffraction peak shifts to a larger angle, which implies that Ni atoms are incorporated into the ZnO lattice. For ZnO:Ni films with good transparency in the visible range, the optical band gap evaluated by the fitting method decreases linearly from 3.272 to 3.253 eV with increasing Ni concentration. Undoped ZnO film exhibits a green emission peak and Ni-doped ZnO films mainly emit a blue photoluminescence centred at 430 nm, we believe that they might be ascribed to crystal defects of oxygen vacancies and interstitial zinc, respectively.

The SiC:Tb films were deposited on porous silicon substrate by rfsputtering. The samples prepared were annealed in N2 atmosphere at different temperatures, and Fourier transform infrared has been used to characterize the structure of them. We observed a strong photoluminescence(PL) spectrum at room temperature in the ultraviolet(UV) and visible regions. We found that the UV emission has obvious changed and a slight blue shift was observed with the change of annealing temperature. The UV and visible PLs were attributed to oxygen deficit center(ODC) and Tb3+ respectively.

Zinc oxide films doped with various contents of copper were deposited on silicon (111) substrates by rf reactive sputtering. The photoluminescent(PL) spectra of the ZnO films were measuered at room temperature. Results showed that each of the samples had a blue band at about 435nm (2.85eV) and the intensities of these blue bands were changed with the variation of content and sputtering power. It was observed that there is a stronger blue bi-peak when the power reaches 150W and the copper content is equal to 2.5%, and there is a stronger blue peak at 437?nm when the power was 100?W and copper content is 1.5% on the PL spectra of ZnO films, the latter had a good c axis orientation. We have investigated the PL properties for various Cu-doped contents and different sputtering powers, and the mechanism of blue emission was also discussed in this paper.

Highly oriented polycrystalline ZnO films have been prepared by rf actively sputtering technique. We have investigated the structural and optical properties of ZnO films. x-ray diffraction was employed to analyze the influence of the post-treatment on the properties of ZnO thin films. The grain size increases with annealing temperature. The shift of the diffraction peak position from its normal powder value was observed. The photoluminescence (PL) spectra of these samples consist of one emission peak centred at 2.9eV.The intensities of PL peaks decrease with increasing annealing temperature. We propose that the emission comes from the interstitial Zn.

Si-containing silicon oxide (SSO) films and Ge-containing silicon oxide (GSO) films were deposited on p-type Si substrates using the RF magnetron sputtering technique with a Si-SiO2 and a Ge-SiO2 composite target, respectively. These films were annealed in a N2 ambient at temperatures from 300 to 1100℃. Using high resolution transmission electron microscopy,nanometer Si particles and nanometer Ge particles were observed in the SSO and GSO films,respectively,after annealing at 900 or 1100℃. All the PL spectra from the two types of films annealed at various temperatures have similar shapes with peak positions around 580nm (～2.1eV). It is indicated that light emission originates from luminescence centers in Si oxide films. The experimental results have been explained reasonably.