Metalorganic chemical vapor deposition of epitaxial perovskite SrIrO ₃ films on (100)SrTiO₃ substrates

(001)_c-oriented 60-70-nm-thick SrIO₃films with a high-pressure-stable perovskite phase were epitaxially grown on (100)SrTiO ₃ substrates by metalorganic chemical vapor deposition, and the crystal structure and the resistivity of the films were investigated. X-ray diffraction techniques including general θ-2θ scan, the rocking curve and high-resolution reciprocal space mapping, were used to determine crystal quality, lattice constant, and crystal structure of the SrIrO ₃ films. It was demonstrated that the film crystal structure was tetragonal distorted by strong mechanical constraints due to the in-plane matching with the lattice parameters of SrTiO₃ substrates, and maintained almost the same unit cell volume as the reported one for the perovskite cubic SrIrO₃ phase. The resistivity of the film at room temperature was 740 μΩ cm, and it decreased with decreasing temperature down to 100 K. Finally, an atomically flat surface was obtained on atomically stepped (100)SrTiO₃ substrates.