Oxygen Diffusion in Vapor‐Deposited Indium Oxide Films

Diffusion measurements were made between 1000 and 1300 K on films of In 2 O 3 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 P O2 1/2 dependence. Near 1.0 Pa P O2 the mechanism began to change to a vacancy mechanism which dominated at P O2 <10 −3 Pa, where diffusivity increased with further decrease in oxygen pressure according to a P O2 −1/2 dependence. Activation energies for interstitial and vacancy diffusion were 166 and 190 kJ/mol, respectively.