Effect of Ba substitution on the microstructure and electrical conductivity of BaxSr1-xRuO3 thin films prepared by laser ablation

BaxSr1-xRuO3 (BSRO) thin films were prepared by laser ablation on quartz substrates at a substrate temperature (T-sub) Of 973 K and an oxygen pressure (Po-2) of 13 Pa. The effect of Ba substitution for Sr on the microstructure and electrical conductivity (sigma) was investigated. (110)-oriented pseudo-cubic BSRO thin films were obtained at a Ba substitution ratio (x) below 0.5. The thin films prepared at x = 0.6 to 0.8 had the 4H-type BaRuO3 (BRO) structure, whereas 9R BRO thin films were obtained at x = 1.0. The BSRO thin films consisted of well-crystallized fine grains. The pseudo-cubic lattice parameter of the BSRO thin films increased linearly from 0.393 to 0.407 with increasing x. The BSRO thin films showed metallic conduction, and the sigma decreased due to lattice expansion with increasing chi. (C) 2008 The Ceramic Society of Japan. All rights reserved.