Oxygen Diffusion in Zinc Oxide Thin Films Deposited by PLD Method

Abstract

Thin films of Zinc Oxide (ZnO) and Mg-alloyed Zinc Oxide ((Zn, Mg)O) were deposited with a pulsed laser deposition method. The oxygen diffusion was evaluated in their films. All of the prepared sample were single-phase having c-axis orientation from results of XRD analysis. The observed diffusion profile of oxygen isotope did not correspond with the calculated values under an assumption with a double layer model near surface of (Zn, Mg)O films. Boltzmann-Matano analysis leaded to a result that the oxygen diffusivity increased with increasing the depth for surface in (Zn, Mg)O films. On the contrary, undoped-ZnO films had similar diffusivity of oxygen ions to the single crystal. These results indicate that the defect concentration of (Zn, Mg)O film increased by the substitution of Mg for Zn in ZnO.