Highly effective strain-induced band-engineering of (111) oriented, direct-gap GeSn crystallized on amorphous SiO{sub 2} layers

Journal Article · Mon Mar 07 00:00:00 EST 2016 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.4943192· OSTI ID:22591409

Li, Haofeng; Wang, Xiaoxin; Liu, Jifeng ^[1]

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1. Thayer School of Engineering, Dartmouth College, 14 Engineering Drive, Hanover, New Hampshire 03755 (United States)

We demonstrate highly effective strain-induced band-engineering of (111) oriented direct-gap Ge{sub 1−x}Sn{sub x} thin films (0.074 < x < 0.085) crystallized on amorphous SiO{sub 2} towards 3D photonic integration. Due to a much smaller Poisson's ratio for (111) vs. (100) orientation, 0.44% thermally induced biaxial tensile strain reduces the direct-gap by 0.125 eV towards enhanced direct-gap semiconductor properties, twice as effective as the tensile strain in Ge(100) films. Correspondingly, the optical response is extended to λ = 2.8 μm. A dilatational deformation potential of a = −12.8 ± 0.8 eV is derived. These GeSn films also demonstrate high thermal stability, offering both excellent direct-gap optoelectronic properties and fabrication/operation robustness for integrated photonics.

• OSTI ID: 22591409
• Journal Information: Applied Physics Letters, Vol. 108, Issue 10; Other Information: (c) 2016 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
DEFORMATION
FABRICATION
LAYERS
ORIENTATION
SEMICONDUCTOR MATERIALS
SILICON OXIDES
STRAINS
THIN FILMS