Rapid densification of sol-gel derived yttria-stabilized zirconia thin films

A method based on X-ray reflectivity was used to study the densification behavior of 8 mol% yttria-stabilized zirconia for use in solid oxide fuel cells. Sol-gel derived thin electrolyte films were prepared via spin coating. Subsequent microwave-assisted rapid thermal annealing at 650-1000 °C resulted in crack-free 70 nm thin films. A maximum density of approximately 95% was achieved within 5 min at 1000 °C. X-ray photoelectron spectroscopy depth analysis on the thin films showed that the shorter annealing times, as opposed to conventional heating, resulted in lower Si concentrations at the top surface and at the substrate interface.