Evolution of strain and composition of Ge islands on Si (001) grown by molecular beam epitaxy during postgrowth annealing

Journal Article · Sun Jun 01 04:00:00 EDT 2008 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.2936965· OSTI ID:21137345

Singha, R K; Das, S; Majumdar, S; Das, K; Dhar, A; Ray, S K ^[1]

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1. Department of Physics and Meteorology, Indian Institute of Technology, Kharagpur 721302 (India)

Self-assembled Ge islands have been grown using a Stranski-Krastanov growth mechanism on Si (001) substrates by solid source molecular beam epitaxy. We performed time varying annealing experiments at a representative temperature of 650 deg. C to study the shape and size evolution of islands for a relatively high Ge coverage. Islands are found to coarsen due to heat treatment via structural and compositional changes through continuous strain relaxation. Different island morphologies, namely, 'pyramids', 'transitional domes', and 'domes' are found during the annealing sequence. The dominant coarsening mechanisms for the temporal evolution of islands of as-grown and annealed samples are explained by the comprehensive analysis of Rutherford back scattering, Raman spectroscopy, high-resolution x-ray diffraction, and atomic force microscopy. A correlation of the morphological evolution with the composition and strain relaxation of grown islands is presented.

• OSTI ID: 21137345
• Journal Information: Journal of Applied Physics, Journal Name: Journal of Applied Physics Journal Issue: 11 Vol. 103; ISSN JAPIAU; ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ANNEALING
ATOMIC FORCE MICROSCOPY
BACKSCATTERING
CRYSTAL GROWTH
GERMANIUM
MAGNETIC ISLANDS
MOLECULAR BEAM EPITAXY
MOLECULAR STRUCTURE
MORPHOLOGY
RAMAN SPECTRA
RAMAN SPECTROSCOPY
RUTHERFORD BACKSCATTERING SPECTROSCOPY
SEMICONDUCTOR MATERIALS
SILICON
THIN FILMS
X-RAY DIFFRACTION