Figure 1 HRXRD results for the SrRuO 3 /SrTiO 3 (001) substrate. (a) XRD θ to 2θ DAPT scan patterns. The left inset shows the rocking curve of the SrRuO3 (200)c peak. FWHM was as small as 0.057°. The right inset shows good oscillations at low angles due to the uniform thickness of about 38 nm. (b) X-ray reciprocal space mapping around the STO (114) plane showed well-developed peaks for SrRuO3 in the lower region and two strong substrate

peaks in the upper region. Figure 2 shows HRXRD results for the SRO111 film. There was a strong SRO film peak near 2θ = 85.03° together with the strongest substrate peak near 2θ = 86.21°. (The peak near 2θ = 85.80° was not due to impurities but to spurious light from the X-ray source.) The calculated lattice constant of the SRO was Epigenetics inhibitor d 222 = 1.140 Å = 3.949 Å/2√3, again indicating a high-quality film. The high

crystallinity of the SRO111 film was also confirmed by the value of the full width at half maximum of the SRO (222) peak. This value was as small as 0.052°, smaller than that of the SRO100 film. The right inset of Figure 2 shows good oscillations at low angles due to the uniform thickness of about 37 nm. X-ray reciprocal space mapping around the STO (312) plane shown in Figure 2b contains well-developed peaks for the SRO111 film in the lower region and two strong substrate peaks in the upper region. The strong peaks for SRO were well centered and the obtained d 111 was consistent with the d 222 obtained in the θ to 2θ scan. The position of the film peak along the horizontal Q x axis was the same as that of the substrate peak, indicating that the SRO111 film was grown

coherently on the STO (111) PD184352 (CI-1040) substrate, with the same in-plane lattice constant. This indicated that the SRO111 film was under compressive strain. When we compared the HRXRD data of the two films, we found that the unit cell volume of the SRO111 film was nearly equal to that of the SRO100 film (V pseudocubic = 3.9052 × 3.949 Å3) and with comparable thicknesses. Figure 2 HRXRD results for the SrRuO 3 /SrTiO 3 (111) substrate. (a) XRD θ to 2θ scan patterns. The left inset shows the rocking curve of the SrRuO3 (222) peak. FWHM was as small as 0.052°. The right inset shows good oscillations at low angles due to the uniform thickness of about 38 nm. (b) X-ray reciprocal space mapping around the STO (312) plane showed well-developed peaks for SrRuO3 in the lower region and two strong substrate peaks in the upper region. We used AFM to observe the surface of the STO (111) substrate, which was used for the growth of the SRO thin film, as shown in Figure 3a. A step-and-terrace structure comparable to that reported previously by harsh etching could be clearly seen [17]. Figures 3b,c shows the surface morphologies of the SRO100 film and the SRO111 film, respectively.