Structural and optical characterization of Si{sub x}Ge{sub 1-x-y}Sn{sub y} alloys grown by molecular beam epitaxy

Journal Article · Mon Apr 02 00:00:00 EDT 2012 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.3701732· OSTI ID:22025501

Lin, Hai ^[1]; Chen, Robert; Yijie, Huo; Kamins, Theodore I; Harris, James S ^[2]; Weisheng, Lu ^[3]

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1. Department of Materials Science and Engineering, Stanford University, Stanford, California 94305 (United States)
2. Department of Electrical Engineering, Stanford University, Stanford, California 94305 (United States)
3. Institute of Photonics, University of Strathclyde, Glasgow G4 0NW (United Kingdom)

Si{sub x}Ge{sub 1-x-y}Sn{sub y} alloys were grown by molecular beam epitaxy at low temperature, followed by ex-situ annealing. The crystal quality of Si{sub x}Ge{sub 1-x-y}Sn{sub y} layers was characterized by atomic force microscopy and transmission electron microscopy. The compositions and lattice constants of the alloys were studied by x-ray photoelectron spectroscopy and x-ray diffraction. The results show that Vegard's law is a good approximation for Si{sub x}Ge{sub 1-x-y}Sn{sub y} alloys. Photoreflectance spectroscopy at room temperature was used to determine the direct bandgap energy of Si{sub x}Ge{sub 1-x-y}Sn{sub y} layers. Analyzing the relationship between composition and direct bandgap energy reveals a negative energy bowing parameter for SiSn.

• OSTI ID: 22025501
• Journal Information: Applied Physics Letters, Vol. 100, Issue 14; Other Information: (c) 2012 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ANNEALING
APPROXIMATIONS
ATOMIC FORCE MICROSCOPY
CRYSTAL GROWTH
CRYSTALS
ENERGY GAP
GERMANIUM ALLOYS
LATTICE PARAMETERS
LAYERS
MOLECULAR BEAM EPITAXY
SILICON ALLOYS
TIN ALLOYS
TRANSMISSION ELECTRON MICROSCOPY
VEGARD LAW
X-RAY DIFFRACTION
X-RAY PHOTOELECTRON SPECTROSCOPY