Epitaxial Growth of La0.7Ba0.3MnO3 Thin Films on SrTiO3 and LaAlO3 Substrates by Metal-Organic Deposition

Abstract

La0.7Ba0.3MnO3 (LBMO) thin films were successfully prepared on SrTiO3 (STO) and LaAlO3 (LAO) single-crystal substrates by metal-organic deposition (MOD). The microstructure and the crystallinity of the LBMO films were examined in detail by high-resolution transmission electron microscopy and electron diffraction. The lattice mismatch between LBMO and STO is small as -0.1%; thus, the LBMO films were found to be epitaxially well grown. However, on the LAO substrate, which has a lattice mismatch of ∼-3.2% with LBMO, the films exhibited interfacial misfit dislocations along the interface. For an IR sensor application, we calculated the temperature coefficient of resistance (TCR) from the R(T) measurements. The films grown on STO substrates exhibited a TCR of approximately 5%/K at 306 K compared with 7%/K at 253 K exhibited by the films grown on LAO substrates.