Pseudomorphic GeSn/Ge(001) quantum wells: Examining indirect band gap bowing

Journal Article · Mon Jul 15 04:00:00 EDT 2013 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.4813913· OSTI ID:22122818

Tonkikh, Alexander A. ^[1]; Eisenschmidt, Christian; Schmidt, Georg ^[2]; Talalaev, Vadim G. ^[1]; Zakharov, Nikolay D.; Werner, Peter ^[1]; Schilling, Joerg ^[3]

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1. Max Planck Institute of Microstructure Physics, Weinberg 2 D-06120, Halle (Saale) (Germany)
2. Institute of Physics, Martin Luther University Halle-Wittenberg, Von-Danckelmann-Platz 3 D-01620, Halle (Saale) (Germany)
3. ZIK SiLi-Nano, Martin Luther University Halle-Wittenberg, Karl-Freiherr-von-Fritsch-Str. 3 D-06120, Halle (Saale) (Germany)

A study of the bandgap character of compressively strained GeSn{sub 0.060-0.091}/Ge(001) quantum wells grown by molecular beam epitaxy is reported. The built-in strain in GeSn wells leads to an increased separation between L and {Gamma} conduction band minima. The prevalent indirect interband transitions in GeSn were probed by photoluminescence spectroscopy. As a result we could simulate the L-valley bowing parameter in GeSn alloys, b{sub L} = 0.80 {+-} 0.06 eV at 10 K. From this we conclude that even compressively strained GeSn/Ge(001) alloys could become direct band gap semiconductors at the Sn-fraction higher than 17.0 at. %.

• OSTI ID: 22122818
• Journal Information: Applied Physics Letters, Journal Name: Applied Physics Letters Journal Issue: 3 Vol. 103; ISSN APPLAB; ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

77 NANOSCIENCE AND NANOTECHNOLOGY
ALLOYS
ENERGY GAP
ENERGY-LEVEL TRANSITIONS
GERMANIUM
GERMANIUM COMPOUNDS
LAYERS
MOLECULAR BEAM EPITAXY
PHOTOLUMINESCENCE
QUANTUM WELLS
SEMICONDUCTOR MATERIALS
SPECTROSCOPY
STRAINS
TIN COMPOUNDS