Electrical properties of YSZ thin films deposited on nanoporous substrates

Thin YSZ (yttria stabilized zirconia) films having sub-micrometer thickness without gas leakage were successfully deposited on anodic nanoporous alumina substrates for low-temperature SOFCs application. By oxidation of metal thin films deposited onto the nanoporous substrates with pore size of 20 nm - 200 nm using DC magnetron sputtering at room temperature, YSZ thin films with thickness of about 30 nm - 300 nm were obtained. During oxidation at high temperature, the metal films were successfully transformed into defect-free oxide thin films and volume expansion induced from oxidation of metal resulted in dense thin films that are free from hydrogen permeation. Conductivity of YSZ thin films with different compositions could be measured at room temperature.