Microstructure and possible strain relaxation mechanisms of La2CuO4+δ thin films grown on LaSrAlO4 and SrTiO3 substrates
- 1. Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, New York 11973 (United States)
- 2. Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York 11973 (United States)
Description
Layered perovskite La2CuO4+δ (LCO) thin films were epitaxially grown on SrTiO3 (STO) and LaSrAlO4 substrates by atomic-layer-by-layer molecular beam epitaxy. The lattice defects and residual strain in these films were investigated by means of transmission electron microscopy and electron energy loss spectroscopy. The LCO films showed a high epitaxial quality with flat interfaces and top surfaces. Misfit dislocations with Burgers vector a<010> and shear defects were frequently observed at or near the film/substrate interfaces and in the films, respectively. In one LCO film, grown on STO at the highest temperature, 700 degree sign C, we observed a two layered structure with the top layer being rhombohedral CuLaO2. In addition, stacking faults were observed in the plane views of one LCO film grown on the STO substrate. The residual strains were evaluated from the associated splitting of Bragg reflection. Possible mechanisms of strain relaxations are discussed based on the observed defects
Additional details
Identifiers
- DOI
- 10.1063/1.2710445;
Publishing Information
- Journal Title
- Journal of Applied Physics
- Journal Volume
- 101
- Journal Issue
- 7
- Journal Page Range
- p. 073906-073906.6
- ISSN
- 0021-8979
- CODEN
- JAPIAU
INIS
- Country of Publication
- United States
- Country of Input or Organization
- International Atomic Energy Agency (IAEA)
- INIS RN
- 39011554
- Subject category
- S36: MATERIALS SCIENCE;
- Descriptors DEI
- ALUMINATES; BRAGG REFLECTION; BURGERS VECTOR; CRYSTAL GROWTH; CUPRATES; DISLOCATIONS; ENERGY-LOSS SPECTROSCOPY; HIGH-TC SUPERCONDUCTORS; LANTHANUM COMPOUNDS; LAYERS; MICROSTRUCTURE; MOLECULAR BEAM EPITAXY; RESIDUAL STRESSES; STACKING FAULTS; STRAINS; STRESS RELAXATION; STRONTIUM TITANATES; SUBSTRATES; THIN FILMS; TRANSMISSION ELECTRON MICROSCOPY
- Descriptors DEC
- ALKALINE EARTH METAL COMPOUNDS; ALUMINIUM COMPOUNDS; COPPER COMPOUNDS; CRYSTAL DEFECTS; CRYSTAL GROWTH METHODS; CRYSTAL STRUCTURE; ELECTRON MICROSCOPY; ELECTRON SPECTROSCOPY; EPITAXY; FILMS; LINE DEFECTS; MICROSCOPY; OXYGEN COMPOUNDS; RARE EARTH COMPOUNDS; REFLECTION; RELAXATION; SPECTROSCOPY; STRESSES; STRONTIUM COMPOUNDS; SUPERCONDUCTORS; TITANATES; TITANIUM COMPOUNDS; TRANSITION ELEMENT COMPOUNDS; TYPE-II SUPERCONDUCTORS
Optional Information
- Notes
- (c) 2007 American Institute of Physics