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Title: Shape oscillations: A walk through the phase diagram of strained islands

Abstract

We observe that the morphology of strained SiGe/Si(001) islands oscillates between shallow and steeper shapes during extensive in situ annealing at the growth temperature. We attribute this result to a competition between coarsening and Si-Ge intermixing as paths to strain relaxation. A simple model, in which the equilibrium island shape depends on volume and the average misfit with the substrate, accounts for the observed behavior. Dislocated islands evolve similarly to coherent islands, with no introduction of additional dislocations throughout the annealing.

Authors:
; ;  [1]; ;  [2];  [1];  [3]
  1. Max-Planck-Institut fuer Festkoerperforschung, Heisenbergstrasse 1, 70569 Stuttgart (Germany)
  2. Institute for Semiconductor Physics, Johannes-Kepler-Universitaet, A-4040 Linz (Austria)
  3. (Germany)
Publication Date:
OSTI Identifier:
20957775
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. B, Condensed Matter and Materials Physics; Journal Volume: 75; Journal Issue: 11; Other Information: DOI: 10.1103/PhysRevB.75.113307; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ANNEALING; DISLOCATIONS; EPITAXY; GERMANIUM ALLOYS; GERMANIUM SILICIDES; LAYERS; MORPHOLOGY; OSCILLATIONS; PHASE DIAGRAMS; RELAXATION; SEMICONDUCTOR MATERIALS; SILICON; SILICON ALLOYS; STRAINS; SUBSTRATES

Citation Formats

Stoffel, M., Rastelli, A., Merdzhanova, T., Stangl, J., Bauer, G., Schmidt, O. G., and Institute for Integrative Nanosciences, IFW Dresden, Helmholtzstrasse 20, 01069 Dresden. Shape oscillations: A walk through the phase diagram of strained islands. United States: N. p., 2007. Web. doi:10.1103/PHYSREVB.75.113307.
Stoffel, M., Rastelli, A., Merdzhanova, T., Stangl, J., Bauer, G., Schmidt, O. G., & Institute for Integrative Nanosciences, IFW Dresden, Helmholtzstrasse 20, 01069 Dresden. Shape oscillations: A walk through the phase diagram of strained islands. United States. doi:10.1103/PHYSREVB.75.113307.
Stoffel, M., Rastelli, A., Merdzhanova, T., Stangl, J., Bauer, G., Schmidt, O. G., and Institute for Integrative Nanosciences, IFW Dresden, Helmholtzstrasse 20, 01069 Dresden. Thu . "Shape oscillations: A walk through the phase diagram of strained islands". United States. doi:10.1103/PHYSREVB.75.113307.
@article{osti_20957775,
title = {Shape oscillations: A walk through the phase diagram of strained islands},
author = {Stoffel, M. and Rastelli, A. and Merdzhanova, T. and Stangl, J. and Bauer, G. and Schmidt, O. G. and Institute for Integrative Nanosciences, IFW Dresden, Helmholtzstrasse 20, 01069 Dresden},
abstractNote = {We observe that the morphology of strained SiGe/Si(001) islands oscillates between shallow and steeper shapes during extensive in situ annealing at the growth temperature. We attribute this result to a competition between coarsening and Si-Ge intermixing as paths to strain relaxation. A simple model, in which the equilibrium island shape depends on volume and the average misfit with the substrate, accounts for the observed behavior. Dislocated islands evolve similarly to coherent islands, with no introduction of additional dislocations throughout the annealing.},
doi = {10.1103/PHYSREVB.75.113307},
journal = {Physical Review. B, Condensed Matter and Materials Physics},
number = 11,
volume = 75,
place = {United States},
year = {Thu Mar 15 00:00:00 EDT 2007},
month = {Thu Mar 15 00:00:00 EDT 2007}
}
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