XRD analysis of strain states in epitaxial YSZ/RE2O3 (REÂ =Â Y, Er) multilayers as a function of layer thickness

The strain in epitaxial multilayers with coherent interfaces between yttria stabilized zirconia and rare earth metal oxides is investigated as a function of the layer thickness. An analytic model was developed to describe the strain, which is analyzed by measuring distinct XRD reflections in two orientations. Applying our model to this data the interface thickness δ0 is estimated. For Y2O3/YSZ multilayers δ0 is 9.3 nm and for Er2O3/YSZ multilayers δ0 is 8.2 nm. Our findings are in accordance with the assumption that mismatch induced stress can be relaxed by elastic deformation.