Optimization of DC Reactive Magnetron Sputtering Deposition Process for Efficient YSZ Electrolyte Thin Film SOFC

Abstract Yttria‐stabilized zirconia (YSZ, ZrO 2 :Y 2 O 3 ) 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 (LaSrMnO 3 ) cathode exhibits a satisfying gastightness (OCV = 900 mV) and a maximum power density of 350 mW cm –2 .