Oxygen Diffusion in Vapor-Deposited Indium Oxide Films

Diffusion measurements were made between 1000 and 1300 K on films of In2O3 by electrochemical techniques using an yttria-stabilized zirconia solid electrolyte. At atmospheric oxygen pressures, diffusion invariably occurred via an oxygen interstitial mechanism. The diffusion coefficient decreased with decreasing oxygen pressure with a PO21/2 dependence. Near 1.0 Pa PO2the mechanism began to change to a vacancy mechanism which dominated at PO2 <10−3 Pa, where diffusivity increased with further decrease in oxygen pressure according to a PO2−1/2 dependence. Activation energies for interstitial and vacancy diffusion were 166 and 190 kJ/mol, respectively.