Phase and structural characterization of Sr{sub 2}Nb{sub 2}O{sub 7} and SrNbO{sub 3} thin films grown via pulsed laser ablation in O{sub 2} or N{sub 2} atmospheres

Journal Article · Tue Apr 15 00:00:00 EDT 2008 · Journal of Solid State Chemistry

DOI:https://doi.org/10.1016/j.jssc.2008.01.007· OSTI ID:21128237

Balasubramaniam, K R; Cao, Y; Patel, N; Havelia, S; Cox, P J; Devlin, E C; Yu, E P; Close, B J ^[1]; Woodward, P M ^[2]

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1. Department of Materials Science and Engineering, Carnegie Mellon University, Pittsburgh, PA 15213 (United States)
2. Department of Chemistry, Ohio State University, Columbus, OH 43210 (United States)

The influence of substrate temperature, process gas, deposition pressure, and substrate type on the phase selection, orientation/epitaxy, and growth morphology of thin films in the SrNbO{sub y} (y{approx}3.0 or 3.5) family was investigated. Pulsed laser deposited films (from a Sr{sub 2}Nb{sub 2}O{sub 7} target) obtained in both oxygen and nitrogen atmospheres upon various substrates were characterized with X-ray diffraction, energy dispersive spectroscopy, atomic force microscopy, and transmission electron microscopy. In oxygen atmospheres, films adopted the (110)-layered perovskite structure of the target. Higher temperatures, lower pressures of oxygen, and use of (110)-oriented SrTiO{sub 3} substrates lead to highly crystalline, epitaxial films of Sr{sub 2}Nb{sub 2}O{sub 7}. The use of nitrogen atmospheres resulted in cubic perovskite SrNbO{sub 3} formation: epitaxial, textured, or polycrystalline films were obtained depending on the substrate; no nitrogen incorporation could be observed on the anion sublattice. On SrTiO{sub 3}, the cubic perovskite films followed a cube-on-cube epitaxy and planar defects were observed to occur on the (110) perovskite planes. - Graphical abstract: Phase selection of SrNbO{sub y} films is influenced primarily by the process gas (in the 1-100 mTorr pressure range). In oxygen, films adopt the Sr{sub 2}Nb{sub 2}O{sub 7} (110)-layered perovskite structure (left). In nitrogen, films adopt the cubic perovskite SrNbO{sub 3} structure (right). The films' microstructure depends, however, on the substrate type and temperature.

• OSTI ID: 21128237
• Journal Information: Journal of Solid State Chemistry, Vol. 181, Issue 4; Other Information: DOI: 10.1016/j.jssc.2008.01.007; PII: S0022-4596(08)00010-8; Copyright (c) 2008 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA); ISSN 0022-4596
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
ABLATION
ATMOSPHERES
ATOMIC FORCE MICROSCOPY
CRYSTAL DEFECTS
DEPOSITION
EPITAXY
MICROSTRUCTURE
MORPHOLOGY
NIOBATES
NITROGEN
OXYGEN
PEROVSKITE
POLYCRYSTALS
PRESSURE RANGE
SPECTROSCOPY
STRONTIUM COMPOUNDS
STRONTIUM TITANATES
THIN FILMS
TRANSMISSION ELECTRON MICROSCOPY
X-RAY DIFFRACTION