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The residual stress in ZrO2 thin films prepared by electron beam evaporation was measured by viewing the substrate deformation using an optical interferometer. The influences of deposition temperature and deposition rate on the residual stress have been studied. The results show that residual stress in ZrO2 thin films varies from tensile to compressive depending on deposition temperature and deposition rate, respectively. The value of compressive stress increases with the increasing of deposition temperature and deposition rate. At the same time, X-ray diffraction measurement was carried out in order to examine the crystallization behavior of the ZrO2 thin films as a function of deposition temperature and deposition rate. The relationship between the residual stress and the microstructure has also been discussed. [Copyright &y& Elsevier]

Abstract: HfO2 films, using metal hafnium as starting material, are deposited by plasma-ion assisted electron evaporation with different Advanced Plasma Source (APS) bias voltages. The refractive index and extinction coefficient are calculated, the chemical state and composition, as well as the stress and aging behavior is investigated. Laser induced damage threshold (LIDT) and damage mechanism are also evaluated and discussed. Optical, structural, mechanical and laser induced damage properties of HfO2 films are found to be sensitive to APS bias voltage. The film stress can be tuned by varying the APS bias voltage. Damage morphologies indicate the LIDT of the HfO2 films at 1064nm and 532nm are dominated by the nodular-defect density in coatings, while the 355nm LIDT is dominated by the film absorption. HfO2 films with higher 1064nm LIDT than samples evaporated from hafnia are achieved with bias voltage of 100V. [Copyright &y& Elsevier]

Abstract: Growth stress in hafnium oxide/silicon dioxide (HfO2/SiO2) multilayers was measured in situ to understand the role of the sublayers and the influence of the underlayers'' structural features. Experiments using three- and six-layer films were performed by electron-beam evaporation. During deposition, the developing trend of the force per unit width was controlled by changing the thickness ratio of the HfO2 and SiO2 layers. The substrate material affected the initial stress evolution of HfO2 film. The structural feature of the HfO2 layer onto which SiO2 was deposited and the whole film thickness have a combined effect on the stress evolution of the SiO2 layer. [Copyright &y& Elsevier]

Abstract: Laser-induced damages to TiO2 single layers and TiO2/SiO2 high reflectors at laser wavelength of 1064 nm, 800 nm, 532 nm, and pulse width of 12 ns, 220 ps, 50 fs, 8 ns are investigated. All films are prepared by electron beam evaporation. The relations among microstructure, chemical composition, optical properties and laser-induced damage threshold (LIDT), have been researched. The dependence of damage mechanism on laser wavelength and pulse width is discussed. It is found that from 1064 nm to 532 nm, LIDT is mainly absorption related, which is determined by film''s extinction coefficient and stoichiometric defects. The rapid decrease of LIDT at 800 nm is due to the pulse width factor. TiO2 coatings are mainly thermally by damaged at long pulse (τ ≥220 ps). The damage shows ablation feature at 50 fs. [Copyright &y& Elsevier]

Abstract: ZrO2 films were prepared by electron beam evaporation with glancing angle deposition (GLAD) technique. The as-deposition and annealed ZrO2 films are all amorphous, different from that deposited at normal incidence. Due to the shadowing effect, a highly orientated structure composed of slanted columns formed, and the obtained films became the mixture of slanted columns and voids. The relationship among the effective refractive index, packing density and flux incident angle was investigated. The refractive index and packing density of ZrO2 films decrease with the increase of the incident angle. The in-plane birefringence of GLAD ZrO2 films was calculated. At the packing density of 0.576, the maximum birefringence is 0.037. [Copyright &y& Elsevier]

Abstract: CO2 laser irradiation experiments on ZnO thin films are reported. The structural, optical, luminescent and vibrational properties of the samples were investigated by X-ray diffraction (XRD), transmittance, photoluminescence (PL) and Raman measurements. XRD results show that the crystalline of the irradiated films was improved. The (002) peaks of irradiated ZnO films shift to higher 2θ angles due to the stress relaxation in the case of laser beam irradiation. From optical transmittance spectra, all films exhibit high transmittance in the visible range, the optical band edge of irradiated films showed a redshift compared with that of as-grown films. Compared with the as-grown films, the photoluminescence emission (in particular the relative intensities of visible emissions) intensities of irradiated samples enhanced. In the Raman scattering spectra, both the A1 and E2 modes exhibited slight Raman blueshift. [Copyright &y& Elsevier]