Temperature Dependent Octahedral Tilting Behaviors of Monoclinic and Tetragonal SrRuO3 Thin Films

We used in-situ synchrotron X-ray scattering to investigate phase transformations of octahedral tilted monoclinic SrRuO 3 (MSRO) and tetragonal SRO (TSRO) thin films on SrTiO 3 (STO) substrates. The octahedral tilted MSRO thin films were highly crystalline and the monoclinic distortion angle was 0.45°. The phase transition temperature from the MSRO to TSRO phase occurred at approximately 200 °C as a second order transition. Conversely, no phase transformations of the TSRO thin film occurred within the range from RT to 250 °C. The octahedral RuO 6 rotation was strongly affected by the phase transformation in the SRO thin films.