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Title: Rolling up SiGe on insulator

Abstract

SiGe on insulator films of 10-50 nm thickness are fabricated by Ge condensation applying different oxidation times. The layers are released from the substrate by selectively etching the insulator film. Due to the varying Ge composition, the layers bend downward toward the substrate surface and roll up into microtubes. Depending on the Ge condensation, the strain distribution in the SiGe layers varies and allows a scaling of the tube diameters between 1 and 4 {mu}m. Assuming pseudomorphic SiGe layers, the tube diameters are smaller than expected from continuum mechanical theory. This suggests the occurrence of additional strain in the oxidized films.

Authors:
; ; ;  [1]
  1. Max-Planck-Institut fuer Festkoerperforschung, Heisenbergstrasse 1, D-70569 Stuttgart (Germany)
Publication Date:
OSTI Identifier:
20971918
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 90; Journal Issue: 19; Other Information: DOI: 10.1063/1.2737425; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; CRYSTAL GROWTH; ETCHING; FILM CONDENSATION; GERMANIUM ALLOYS; GERMANIUM SILICIDES; LAYERS; MOLECULAR BEAM EPITAXY; OXIDATION; RESIDUAL STRESSES; SEMICONDUCTOR MATERIALS; SILICON ALLOYS; STRAINS; SUBSTRATES; THIN FILMS

Citation Formats

Cavallo, F., Songmuang, R., Ulrich, C., and Schmidt, O. G.. Rolling up SiGe on insulator. United States: N. p., 2007. Web. doi:10.1063/1.2737425.
Cavallo, F., Songmuang, R., Ulrich, C., & Schmidt, O. G.. Rolling up SiGe on insulator. United States. doi:10.1063/1.2737425.
Cavallo, F., Songmuang, R., Ulrich, C., and Schmidt, O. G.. Mon . "Rolling up SiGe on insulator". United States. doi:10.1063/1.2737425.
@article{osti_20971918,
title = {Rolling up SiGe on insulator},
author = {Cavallo, F. and Songmuang, R. and Ulrich, C. and Schmidt, O. G.},
abstractNote = {SiGe on insulator films of 10-50 nm thickness are fabricated by Ge condensation applying different oxidation times. The layers are released from the substrate by selectively etching the insulator film. Due to the varying Ge composition, the layers bend downward toward the substrate surface and roll up into microtubes. Depending on the Ge condensation, the strain distribution in the SiGe layers varies and allows a scaling of the tube diameters between 1 and 4 {mu}m. Assuming pseudomorphic SiGe layers, the tube diameters are smaller than expected from continuum mechanical theory. This suggests the occurrence of additional strain in the oxidized films.},
doi = {10.1063/1.2737425},
journal = {Applied Physics Letters},
number = 19,
volume = 90,
place = {United States},
year = {Mon May 07 00:00:00 EDT 2007},
month = {Mon May 07 00:00:00 EDT 2007}
}
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  • Abstract not provided.
  • Effects of H{sup +} implantation ({<=}5x10{sup 16} cm{sup -2}) on stress relaxation in an oxidation-induced Ge condensation method have been investigated to form stress-relaxed ultrathin ({approx}30 nm) SiGe-on-insulator (SGOI) virtual substrates. High-dose ({>=}10{sup 15} cm{sup -2}) implantation enhanced stress relaxation, which was attributed to bond breaking at the SiGe/buried SiO{sub 2} interface. However, oxidation velocity was also enhanced due to irradiation defects. Two-step annealing (500 deg. C for 30 min and 850 deg. C for 60 min) before oxidation was proposed to remove irradiation defects. This achieved enhanced stress relaxation in ultrathin SGOI without changing oxidation velocity.
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