Influence of deposition temperature and bias voltage on the crystalline phase of Er2O3 thin films deposited by filtered cathodic arc

Er2O3 thin films on Eurofer steel substrates were produced by a filtered cathodic arc device, varying the substrate temperature (RT – 700 °C) and sample bias (0 to −450 V). The crystallographic phase was analyzed by X-ray diffraction and Raman spectroscopy. Deposition at ⩾600 °C without bias lead to solely formation of the cubic Er2O3 phase. Thin films of the uncommon, monoclinic B-phase were prepared with a negative bias voltage of ⩾100 V at RT, and at temperatures ⩽500 °C for −250 V bias. The B-phase films exhibit a strongly textured film structure. Residual stress measurements show high compressive stress for B-phase films deposited at RT.