Effects of post‐growth annealing on physical properties of SrRuO 3 thin film grown by MOCVD

We report on the annealing effects on strontium ruthenate thin films deposited on SrTiO 3 using liquid‐delivery metalorganic chemical vapor deposition (MOCVD). The results of high resolution X‐ray diffraction (HR‐XRD), Raman spectroscopy, atomic force microscopy (AFM), and electrical resistivity, before and after a post‐growth annealing process were analyzed and compared. XRD and Raman spectroscopy for the as‐deposited film revealed that the film had c ‐axis orientation and contained RuO 2 as secondary phase. Single phase SrRuO 3 could be obtained by annealing the film at 700 °C. Annealing at higher temperatures up to 850 °C leads to ruthenium deficiency, which is revealed by an increase in the out‐of‐plane lattice parameter, while at even higher annealing temperatures a decrease in the out‐of‐plane lattice parameter was detected might be due to diffusion of Ti from the substrate. The electrical resistivity increased with increasing annealing temperature up to 950 °C and showed typical metallic temperature dependence, while for the film annealed at 1000 °C a semiconductor‐like behavior was observed.