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Title: Diffuse x-ray scattering from misfit and threading dislocations in PbTe/BaF{sub 2}/Si(111) thin layers

Abstract

Diffuse x-ray scattering from epitaxial PbTe layers on Si(111) is analyzed both theoretically and experimentally. Reciprocal-space maps and x-ray diffraction profiles are measured and simulated for symmetrical and asymmetrical diffractions as well. The intensity distribution of diffusively scattered radiation is simulated within the statistical theory of x-ray scattering. Both types of expected defects--misfit and threading dislocations--are discussed. Comparing simulated maps to measured ones we can distinguish between contributions arising from misfit and threading dislocations. In the case of PbTe thin layers, the majority diffuse scattering comes from misfit dislocations.

Authors:
;  [1]
  1. Department of Physics of Electronic Structures, Charles University, Ke Karlovu 5, 121 16 Prague (Czech Republic)
Publication Date:
OSTI Identifier:
20787811
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. B, Condensed Matter and Materials Physics; Journal Volume: 73; Journal Issue: 1; Other Information: DOI: 10.1103/PhysRevB.73.014102; (c) 2006 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; BARIUM FLUORIDES; DIFFUSE SCATTERING; DISLOCATIONS; DISTRIBUTION; EPITAXY; INTERFACES; LAYERS; LEAD TELLURIDES; SEMICONDUCTOR MATERIALS; SILICON; THIN FILMS; X-RAY DIFFRACTION

Citation Formats

Danis, S., and Holy, V. Diffuse x-ray scattering from misfit and threading dislocations in PbTe/BaF{sub 2}/Si(111) thin layers. United States: N. p., 2006. Web. doi:10.1103/PHYSREVB.73.0.
Danis, S., & Holy, V. Diffuse x-ray scattering from misfit and threading dislocations in PbTe/BaF{sub 2}/Si(111) thin layers. United States. doi:10.1103/PHYSREVB.73.0.
Danis, S., and Holy, V. Sun . "Diffuse x-ray scattering from misfit and threading dislocations in PbTe/BaF{sub 2}/Si(111) thin layers". United States. doi:10.1103/PHYSREVB.73.0.
@article{osti_20787811,
title = {Diffuse x-ray scattering from misfit and threading dislocations in PbTe/BaF{sub 2}/Si(111) thin layers},
author = {Danis, S. and Holy, V.},
abstractNote = {Diffuse x-ray scattering from epitaxial PbTe layers on Si(111) is analyzed both theoretically and experimentally. Reciprocal-space maps and x-ray diffraction profiles are measured and simulated for symmetrical and asymmetrical diffractions as well. The intensity distribution of diffusively scattered radiation is simulated within the statistical theory of x-ray scattering. Both types of expected defects--misfit and threading dislocations--are discussed. Comparing simulated maps to measured ones we can distinguish between contributions arising from misfit and threading dislocations. In the case of PbTe thin layers, the majority diffuse scattering comes from misfit dislocations.},
doi = {10.1103/PHYSREVB.73.0},
journal = {Physical Review. B, Condensed Matter and Materials Physics},
number = 1,
volume = 73,
place = {United States},
year = {Sun Jan 01 00:00:00 EST 2006},
month = {Sun Jan 01 00:00:00 EST 2006}
}
  • Diffuse x-ray scattering from threading dislocations in epitaxial structures is simulated numerically by a Monte Carlo method. The method allows one to simulate diffraction curves for dislocation types, where macroscopic approaches fail. That includes dislocation types for which analytical ensemble averaging is not feasible as well as microdiffraction curves from small sample volumes. In the latter case, the degree of statistic fluctuation of characteristic features is determined. The Monte Carlo method makes it possible to correlate quantitatively the widths of the microdiffraction curves to the densities of various dislocation types. The potential of the method has been demonstrated by amore » quantitative estimation of the density distribution of edge and screw threading dislocations in laterally overgrown epitaxial GaN structures, which is investigated by a full-field microdiffraction imaging technique. Measuring the asymptotic behavior of the microdiffraction curves allows one to conclude on the prevailing type of threading dislocations.« less
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