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Title: Composition-dependent structural properties in ScGaN alloy films: A combined experimental and theoretical study

Abstract

Experimental and theoretical results are presented regarding the incorporation of scandium into wurtzite GaN. Variation of the a and c lattice constants with Sc fraction in the low Sc concentration regime (0%-17%) are found that can be well explained by the predictions of first-principles theory. The calculations allow a statistical analysis of the variations of the bond lengths and bond angles as functions of Sc concentration. The results are compared to predictions from both a prior experimental study [Constantin et al., Phys. Rev. B 70, 193309 (2004)] and a prior theoretical study [Farrer and Bellaiche et al. Phys. Rev. B 66, 201203(R) (2002)]. It is found that the ScGaN lattice can be very well modeled as being wurtzitelike but with local lattice distortions arising from the incorporation of the Sc atoms. Effects of the addition of Sc on the stacking order for a large Sc fraction is also studied by high resolution transmission electron microscopy. The results show the existence of stacking faults, and induced stacking disorder. The explanation for the lattice constant variations is based on the effects of local lattice distortions and not related to the stacking faults.

Authors:
; ; ; ; ; ;  [1];  [2];  [3];  [2]
  1. Condensed Matter and Surface Science Program, Department of Physics and Astronomy, Ohio University, Athens, Ohio 45701 (United States)
  2. (Spain)
  3. (United States)
Publication Date:
OSTI Identifier:
20787717
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 98; Journal Issue: 12; Other Information: DOI: 10.1063/1.2140889; (c) 2005 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; BOND ANGLE; BOND LENGTHS; GALLIUM ALLOYS; GALLIUM NITRIDES; LATTICE PARAMETERS; NITROGEN ADDITIONS; SCANDIUM ALLOYS; SCANDIUM COMPOUNDS; SEMICONDUCTOR MATERIALS; STACKING FAULTS; THIN FILMS; TRANSMISSION ELECTRON MICROSCOPY

Citation Formats

Constantin, Costel, Haider, Muhammad B., Ingram, David, Smith, Arthur R., Sandler, Nancy, Sun, Kai, Ordejon, Pablo, Condensed Matter and Surface Science Program, Department of Physics and Astronomy, Ohio University, Athens, Ohio 45701 and Institut de Ciencia de Materials de Barcelona-CSIC, Campus UAB, Barcelona, 08193, Electron Microbeam Analysis Laboratory, University of Michigan, Ann Arbor, Michigan 48109-2143, and Institut de Ciencia de Materials de Barcelona-CSIC, Campus UAB, Barcelona, 08193. Composition-dependent structural properties in ScGaN alloy films: A combined experimental and theoretical study. United States: N. p., 2005. Web. doi:10.1063/1.2140889.
Constantin, Costel, Haider, Muhammad B., Ingram, David, Smith, Arthur R., Sandler, Nancy, Sun, Kai, Ordejon, Pablo, Condensed Matter and Surface Science Program, Department of Physics and Astronomy, Ohio University, Athens, Ohio 45701 and Institut de Ciencia de Materials de Barcelona-CSIC, Campus UAB, Barcelona, 08193, Electron Microbeam Analysis Laboratory, University of Michigan, Ann Arbor, Michigan 48109-2143, & Institut de Ciencia de Materials de Barcelona-CSIC, Campus UAB, Barcelona, 08193. Composition-dependent structural properties in ScGaN alloy films: A combined experimental and theoretical study. United States. doi:10.1063/1.2140889.
Constantin, Costel, Haider, Muhammad B., Ingram, David, Smith, Arthur R., Sandler, Nancy, Sun, Kai, Ordejon, Pablo, Condensed Matter and Surface Science Program, Department of Physics and Astronomy, Ohio University, Athens, Ohio 45701 and Institut de Ciencia de Materials de Barcelona-CSIC, Campus UAB, Barcelona, 08193, Electron Microbeam Analysis Laboratory, University of Michigan, Ann Arbor, Michigan 48109-2143, and Institut de Ciencia de Materials de Barcelona-CSIC, Campus UAB, Barcelona, 08193. Thu . "Composition-dependent structural properties in ScGaN alloy films: A combined experimental and theoretical study". United States. doi:10.1063/1.2140889.
@article{osti_20787717,
title = {Composition-dependent structural properties in ScGaN alloy films: A combined experimental and theoretical study},
author = {Constantin, Costel and Haider, Muhammad B. and Ingram, David and Smith, Arthur R. and Sandler, Nancy and Sun, Kai and Ordejon, Pablo and Condensed Matter and Surface Science Program, Department of Physics and Astronomy, Ohio University, Athens, Ohio 45701 and Institut de Ciencia de Materials de Barcelona-CSIC, Campus UAB, Barcelona, 08193 and Electron Microbeam Analysis Laboratory, University of Michigan, Ann Arbor, Michigan 48109-2143 and Institut de Ciencia de Materials de Barcelona-CSIC, Campus UAB, Barcelona, 08193},
abstractNote = {Experimental and theoretical results are presented regarding the incorporation of scandium into wurtzite GaN. Variation of the a and c lattice constants with Sc fraction in the low Sc concentration regime (0%-17%) are found that can be well explained by the predictions of first-principles theory. The calculations allow a statistical analysis of the variations of the bond lengths and bond angles as functions of Sc concentration. The results are compared to predictions from both a prior experimental study [Constantin et al., Phys. Rev. B 70, 193309 (2004)] and a prior theoretical study [Farrer and Bellaiche et al. Phys. Rev. B 66, 201203(R) (2002)]. It is found that the ScGaN lattice can be very well modeled as being wurtzitelike but with local lattice distortions arising from the incorporation of the Sc atoms. Effects of the addition of Sc on the stacking order for a large Sc fraction is also studied by high resolution transmission electron microscopy. The results show the existence of stacking faults, and induced stacking disorder. The explanation for the lattice constant variations is based on the effects of local lattice distortions and not related to the stacking faults.},
doi = {10.1063/1.2140889},
journal = {Journal of Applied Physics},
number = 12,
volume = 98,
place = {United States},
year = {Thu Dec 15 00:00:00 EST 2005},
month = {Thu Dec 15 00:00:00 EST 2005}
}
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