Optimization of DC reactive magnetron sputtering deposition process for efficient YSZ electrolyte thin film SOFC

Yttria-stabilized zirconia (YSZ, ZrO2:Y2O3) thin films were deposited by reactive DC magnetron sputtering with a high deposition rate from a metallic target of Zr/Y in an argon/oxygen atmosphere. Plasma parameters and composition analysis of the gas phase reveal that the sputtering process in the “compound” mode is reached for a 2.5 sccm oxygen flow rate. Deposition onto silicon in “metal” mode at a flow rate close to the transition, allows obtaining at very high deposition rates (> 10 μm.h -1 ) a compact columnar stoichiometric crystallized YSZ film. When deposited on NiO-YSZ commercial anode, the obtained coatings show the same properties. In spite of the complexity of the substrate (roughness and porosity), a compact and conformed layer was formed. Annealing treatments in air or hydrogen do not significantly alter the structure of the layers. Electrochemical test at 850°C with a screen-printed LSM (LaSrMnO3) cathode exhibits a satisfying gastightness (OCV=900 mV) and a maximum power density of 350 mW.cm -2 .