We demonstrate that completely dense yttria-stabilized zirconia (YSZ) electrolyte films <5 pm thick can be reactively sputter deposited onto porous (∼0.5 μm pore size) La0.8Sr0.2MnO3 substrate/electrodes. The two key factors in achieving the fully dense films were porous substrate preparation and the use of substrate bias during YSZ film deposition. Increasing the negative dc substrate bias Vs from 0 to 300 V produced increasingly dense and flat-surfaced films: Vs = 75 V was chosen to yield high density without excessive film compressive stresses. Solid oxide fuel cells consisting of sputtered YSZ films (Vs = 75 V) and a Ni-YSZ fuel electrode on LSM exhibited open-circuit voltage values within 5% of the theoretical values for thicknesses down to 2 pm. Cells deposited with Vs= 0 V short-circuited at thicknesses of 12 pm or less.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Renewable Energy, Sustainability and the Environment
- Surfaces, Coatings and Films
- Materials Chemistry