Papers by Keyword: Thin Film Characterization

Abstract: Thin films of zirconium oxide have been deposited using pulsed laser deposition on Zr-base alloy substrates, held at 300 K, 573 K and 873 K, in order to understand the effect of substrate temperature on the deposited film. In this study, a KrF excimer laser having 30 ns pulse width and 600 mJ energy at source has been used for depositing the films from a sintered ZrO₂ target using a laser fluence of 5 J.cm^-2. After visual observation, deposited thin films were examined using Raman Spectroscopy (RS) and X-ray Photo-electron Spectroscopy (XPS). It has been found that the oxide deposited at 300 K temperature does not show good adherence with the substrate. The oxide films deposited at 573 K and 873 K are found to be adherent with the substrate and lustrous black in appearance. Thin films of zirconia, deposited using pulsed laser on the Zr-base metallic substrate are initially in amorphous state and possibly little deficient in oxygen. The substrate temperature and the duration of holding at high temperature are responsible for the evolution of nanocrystals in the deposited thin films. The stoichiometry of the amorphous oxide film supports its crystallization, below 573 K, into monoclinic and tetragonal phases and not into cubic phase.

Abstract: Boron-doped hydrogenated amorphous silicon (a-Si:H(B)) thin films have been prepared by DC magnetron sputtering technique under argon and hydrogen mixture. The films were deposited at various hydrogen pressures between 0 and 9 10-5 mbar. The boron concentration estimated from Secondary Ion Mass Spectrometry (SIMS) analysis was found to be around 1.5 1021 cm-3 for all samples. Their physico-chemical, optical and electrical properties are investigated. The physico-chemical properties were studied by infrared absorption measurements. The bonded hydrogen content in the films is then determined using the absorption band of stretching mode. The optical transmission measurements show an increase of the static refractive index and a decrease of optical gap value when hydrogen pressure increases. The dark-conductivity and the photo-conductivity measurements according to the temperature are also reported. We have observed the decreasing of dark-conductivity when hydrogen pressure increases. A slight sensitivity of light was observed for the film deposited at the highest hydrogen pressure. The dark-conductivity was affected by annealing temperature for the whole of the films through its increase in the annealing temperature region 200-350°C.