Microstructure of epitaxial La{sub 0.7}Ca{sub 0.3}MnO{sub 3} thin films grown on LaAlO{sub 3} and SrTiO{sub 3}
- Beijing Laboratory of Electron Microscopy, Center for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, P.O. Box 2724, Beijing 100080, People's Republic of China (China)
- Department of Physics and Astronomy, California State University-Long Beach, Long Beach, California 90840 (United States)
- Mail Stop K763, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)
Epitaxial La{sub 0.7}Ca{sub 0.3}MnO{sub 3} (LCMO) thin films of a thickness {approx}170 nm were grown on (001) LaAlO{sub 3} (LAO) and (001) SrTiO{sub 3} (STO) substrates by pulsed laser deposition. Transmission electron microscopy and associated techniques have been applied to investigate the microstructures introduced by lattice mismatch that are responsible for the observed differences in properties between these two films. Numerous secondary phase rods were observed in both films. For the LCMO/LAO film, Ca-deficient secondary-phase rods originated in the film after a thickness of about 25 nm and were found to be responsible for relieving in-plane compressive stress during the island growth. In the case of STO substrate, however, almost all of secondary-phase rods initiated at the film-substrate interface. The lattice mismatch between LCMO and STO is relaxed into regions of good coherent fit separated by such secondary phases, possibly resulting from interfacial reaction. The two types of substrates lead to the formation of two different crystallographic domain structures in the LCMO films. The film on LAO exhibits an almost pure [110] out-of-plane texture with 90 degree sign domains in plane. In contrast, the film grown on STO consists of mixed domains of [001] and [110] orientations and is dominated by [001] texture. (c) 2000 American Institute of Physics.
- OSTI ID:
- 20217676
- Journal Information:
- Journal of Applied Physics, Journal Name: Journal of Applied Physics Journal Issue: 7 Vol. 88; ISSN JAPIAU; ISSN 0021-8979
- Country of Publication:
- United States
- Language:
- English
Similar Records
X-ray analysis of strain distribution in two-step grown epitaxial SrTiO{sub 3} thin films
Anisotropic-strain-relaxation-induced crosshatch morphology in epitaxial SrTiO{sub 3}/NdGaO{sub 3} thin films