Estimation of residual stresses in perovskite films for capacitor applications

The performance of perovskite films in capacitor devices is strongly determined by the level of residual stresses developed after their fabrication at high temperatures. Quantification of these stresses by X-ray diffraction is not straightforward in perovskite films due to the complexity of the crystalline structure and a lack of effective elastic diffraction constants. In this work we apply a simple and accurate method to estimate the residual stresses developed in Pb(Nb,Zr,Ti)O3 perovskite films grown by metal-organic chemical vapor deposition on the Pt electrode. The stress was directly measured in the Pt bottom electrode film before and after the deposition of the perovskite film and compared with intrinsic and thermal stresses calculations. Our results reveal in-plane tensile stresses of 676(8) MPa developed in the Pt electrode, which mainly originate from the relative thermal contraction between Pb(Nb,Zr,Ti)O3 and Pt as well as the cubic-tetragonal perovskite phase transformation after deposition. This methodology is straightforward and highlights the possibility to perform systematic studying for tailoring stress conditions and improving the performance of perovskite films for capacitor applications.