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Title: Surfactant-Mediated Epitaxy of Germanium on Structured Silicon Substrates: Towards Embedded Germanium

Abstract

As a first step towards germanium embedded in silicon wafers, we investigated the surfactant-mediated epitaxy of Ge on structured Si substrates. High-resolution x-ray diffraction (XRD) showed that the Ge-films are <001>-oriented and fully relaxed. Transmission electron microscopy (TEM) inspection in cross-section and plan view revealed uniform films of high structural perfection comparable to those obtained on non-structured wafers. A regular misfit dislocation network is found at the Ge/Si interface at the bottom of the wells, the <111>-oriented side-walls, and the non-etched areas. No defect accumulation was observed at kinks or side-walls. We conclude that the growth mode is not affected by the different surface orientations present on the substrate.

Authors:
; ;  [1]
  1. Institute for Semiconductor Devices and Materials (MBE), University of Hannover, Appelstr. 11a, D-30167 Hannover (Germany)
Publication Date:
OSTI Identifier:
21055062
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 893; Journal Issue: 1; Conference: ICPS 2006: 28. international conference on the physics of semiconductors, Vienna (Austria), 24-28 Jul 2006; Other Information: DOI: 10.1063/1.2729773; (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; CROSS SECTIONS; CRYSTAL GROWTH; DISLOCATIONS; EPITAXY; FILMS; GERMANIUM; INTERFACES; ORIENTATION; RESOLUTION; SILICON; SUBSTRATES; SURFACES; SURFACTANTS; TRANSMISSION ELECTRON MICROSCOPY; X-RAY DIFFRACTION

Citation Formats

Wietler, T. F., Bugiel, E., and Hofmann, K. R. Surfactant-Mediated Epitaxy of Germanium on Structured Silicon Substrates: Towards Embedded Germanium. United States: N. p., 2007. Web. doi:10.1063/1.2729773.
Wietler, T. F., Bugiel, E., & Hofmann, K. R. Surfactant-Mediated Epitaxy of Germanium on Structured Silicon Substrates: Towards Embedded Germanium. United States. doi:10.1063/1.2729773.
Wietler, T. F., Bugiel, E., and Hofmann, K. R. Tue . "Surfactant-Mediated Epitaxy of Germanium on Structured Silicon Substrates: Towards Embedded Germanium". United States. doi:10.1063/1.2729773.
@article{osti_21055062,
title = {Surfactant-Mediated Epitaxy of Germanium on Structured Silicon Substrates: Towards Embedded Germanium},
author = {Wietler, T. F. and Bugiel, E. and Hofmann, K. R.},
abstractNote = {As a first step towards germanium embedded in silicon wafers, we investigated the surfactant-mediated epitaxy of Ge on structured Si substrates. High-resolution x-ray diffraction (XRD) showed that the Ge-films are <001>-oriented and fully relaxed. Transmission electron microscopy (TEM) inspection in cross-section and plan view revealed uniform films of high structural perfection comparable to those obtained on non-structured wafers. A regular misfit dislocation network is found at the Ge/Si interface at the bottom of the wells, the <111>-oriented side-walls, and the non-etched areas. No defect accumulation was observed at kinks or side-walls. We conclude that the growth mode is not affected by the different surface orientations present on the substrate.},
doi = {10.1063/1.2729773},
journal = {AIP Conference Proceedings},
number = 1,
volume = 893,
place = {United States},
year = {Tue Apr 10 00:00:00 EDT 2007},
month = {Tue Apr 10 00:00:00 EDT 2007}
}
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