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Title: Thermal stability and relaxation mechanisms in compressively strained Ge{sub 0.94}Sn{sub 0.06} thin films grown by molecular beam epitaxy

Abstract

Strained Ge{sub 1-x}Sn{sub x} thin films have recently attracted a lot of attention as promising high mobility or light emitting materials for future micro- and optoelectronic devices. While they can be grown nowadays with high crystal quality, the mechanism by which strain energy is relieved upon thermal treatments remains speculative. To this end, we investigated the evolution (and the interplay) of composition, strain, and morphology of strained Ge{sub 0.94}Sn{sub 0.06} films with temperature. We observed a diffusion-driven formation of Sn-enriched islands (and their self-organization) as well as surface depressions (pits), resulting in phase separation and (local) reduction in strain energy, respectively. Remarkably, these compositional and morphological instabilities were found to be the dominating mechanisms to relieve energy, implying that the relaxation via misfit generation and propagation is not intrinsic to compressively strained Ge{sub 0.94}Sn{sub 0.06} films grown by molecular beam epitaxy.

Authors:
; ; ;  [1];  [2]; ; ;  [3];  [1];  [2];  [4]; ;  [5];  [6];  [7]; ;  [1]
  1. Instituut voor Kern-en Stralingsfysica, KU Leuven, Celestijnenlaan 200D, 3001 Leuven (Belgium)
  2. (Belgium)
  3. Physikalisch-Technische Bundesanstalt (PTB), Abbestraße 2-12, 10587 Berlin (Germany)
  4. (Germany)
  5. imec, Kapeldreef 75, 3001 Leuven (Belgium)
  6. Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603 (Japan)
  7. Nanoelectronics Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba West SCR, 16-1 Onogawa, Tsukuba, Ibaraki 305-8569 (Japan)
Publication Date:
OSTI Identifier:
22598843
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 120; Journal Issue: 8; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; CRYSTALS; DIFFUSION; GERMANIUM; HEAT TREATMENTS; INSTABILITY; MOLECULAR BEAM EPITAXY; MORPHOLOGY; OPTOELECTRONIC DEVICES; RELAXATION; SPECTROSCOPY; STABILITY; STRAINS; SURFACES; THIN FILMS; TIN

Citation Formats

Fleischmann, C., Lieten, R. R., Shimura, Y., Vandervorst, W., imec, Kapeldreef 75, 3001 Leuven, Hermann, P., Hönicke, P., Beckhoff, B., Seidel, F., imec, Kapeldreef 75, 3001 Leuven, Institut für Elektronik-und Sensormaterialien, TU Bergakademie Freiberg, Gustav-Zeuner-Str. 3, 09599 Freiberg, Richard, O., Bender, H., Zaima, S., Uchida, N., Temst, K., and Vantomme, A. Thermal stability and relaxation mechanisms in compressively strained Ge{sub 0.94}Sn{sub 0.06} thin films grown by molecular beam epitaxy. United States: N. p., 2016. Web. doi:10.1063/1.4961396.
Fleischmann, C., Lieten, R. R., Shimura, Y., Vandervorst, W., imec, Kapeldreef 75, 3001 Leuven, Hermann, P., Hönicke, P., Beckhoff, B., Seidel, F., imec, Kapeldreef 75, 3001 Leuven, Institut für Elektronik-und Sensormaterialien, TU Bergakademie Freiberg, Gustav-Zeuner-Str. 3, 09599 Freiberg, Richard, O., Bender, H., Zaima, S., Uchida, N., Temst, K., & Vantomme, A. Thermal stability and relaxation mechanisms in compressively strained Ge{sub 0.94}Sn{sub 0.06} thin films grown by molecular beam epitaxy. United States. doi:10.1063/1.4961396.
Fleischmann, C., Lieten, R. R., Shimura, Y., Vandervorst, W., imec, Kapeldreef 75, 3001 Leuven, Hermann, P., Hönicke, P., Beckhoff, B., Seidel, F., imec, Kapeldreef 75, 3001 Leuven, Institut für Elektronik-und Sensormaterialien, TU Bergakademie Freiberg, Gustav-Zeuner-Str. 3, 09599 Freiberg, Richard, O., Bender, H., Zaima, S., Uchida, N., Temst, K., and Vantomme, A. 2016. "Thermal stability and relaxation mechanisms in compressively strained Ge{sub 0.94}Sn{sub 0.06} thin films grown by molecular beam epitaxy". United States. doi:10.1063/1.4961396.
@article{osti_22598843,
title = {Thermal stability and relaxation mechanisms in compressively strained Ge{sub 0.94}Sn{sub 0.06} thin films grown by molecular beam epitaxy},
author = {Fleischmann, C. and Lieten, R. R. and Shimura, Y. and Vandervorst, W. and imec, Kapeldreef 75, 3001 Leuven and Hermann, P. and Hönicke, P. and Beckhoff, B. and Seidel, F. and imec, Kapeldreef 75, 3001 Leuven and Institut für Elektronik-und Sensormaterialien, TU Bergakademie Freiberg, Gustav-Zeuner-Str. 3, 09599 Freiberg and Richard, O. and Bender, H. and Zaima, S. and Uchida, N. and Temst, K. and Vantomme, A.},
abstractNote = {Strained Ge{sub 1-x}Sn{sub x} thin films have recently attracted a lot of attention as promising high mobility or light emitting materials for future micro- and optoelectronic devices. While they can be grown nowadays with high crystal quality, the mechanism by which strain energy is relieved upon thermal treatments remains speculative. To this end, we investigated the evolution (and the interplay) of composition, strain, and morphology of strained Ge{sub 0.94}Sn{sub 0.06} films with temperature. We observed a diffusion-driven formation of Sn-enriched islands (and their self-organization) as well as surface depressions (pits), resulting in phase separation and (local) reduction in strain energy, respectively. Remarkably, these compositional and morphological instabilities were found to be the dominating mechanisms to relieve energy, implying that the relaxation via misfit generation and propagation is not intrinsic to compressively strained Ge{sub 0.94}Sn{sub 0.06} films grown by molecular beam epitaxy.},
doi = {10.1063/1.4961396},
journal = {Journal of Applied Physics},
number = 8,
volume = 120,
place = {United States},
year = 2016,
month = 8
}
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