Growth mechanisms of GaSb heteroepitaxial films on Si with an AlSb buffer layer

Journal Article · Sat Sep 21 04:00:00 EDT 2013 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.4820255· OSTI ID:22217998

Vajargah, S. Hosseini; Botton, G. A. ^[1]; Ghanad-Tavakoli, S. ^[2]; Preston, J. S.; Kleiman, R. N. ^[3]

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1. Department of Materials Science and Engineering, McMaster University, Hamilton, Ontario L8S 4L7 (Canada)
2. Centre for Emerging Device Technologies, McMaster University, Hamilton, Ontario L8S 4L7 (Canada)
3. Brockhouse Institute for Materials Research, McMaster University, Hamilton, Ontario L8S 4M1 (Canada)

The initial growth stages of GaSb epilayers on Si substrates and the role of the AlSb buffer layer were studied by high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM). Heteroepitaxy of GaSb and AlSb on Si both occur by Volmer-Weber (i.e., island mode) growth. However, the AlSb and GaSb islands have distinctly different characteristics as revealed through an atomic-resolution structural study using Z-contrast of HAADF-STEM imaging. While GaSb islands are sparse and three dimensional, AlSb islands are numerous and flattened. The introduction of 3D island-forming AlSb buffer layer facilitates the nucleation of GaSb islands. The AlSb islands-assisted nucleation of GaSb islands results in the formation of drastically higher quality planar film at a significantly smaller thickness of films. The interface of the AlSb and GaSb epilayers with the Si substrate was further investigated with energy dispersive X-ray spectrometry to elucidate the key role of the AlSb buffer layer in the growth of GaSb epilayers on Si substrates.

• OSTI ID: 22217998
• Journal Information: Journal of Applied Physics, Journal Name: Journal of Applied Physics Journal Issue: 11 Vol. 114; ISSN JAPIAU; ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
ALUMINIUM COMPOUNDS
CHEMICAL ANALYSIS
FILMS
GALLIUM ANTIMONIDES
INTERFACES
LAYERS
MOLECULAR BEAM EPITAXY
NUCLEATION
RESOLUTION
SUBSTRATES
THICKNESS
TRANSMISSION ELECTRON MICROSCOPY
X RADIATION
X-RAY SPECTROSCOPY