Quality-enhanced In{sub 0.3}Ga{sub 0.7}As film grown on GaAs substrate with an ultrathin amorphous In{sub 0.6}Ga{sub 0.4}As buffer layer

Journal Article · Mon Jan 27 00:00:00 EST 2014 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.4863232· OSTI ID:22280557

Gao, Fangliang; Li, Guoqiang ^[1]

---

1. State Key Laboratory of Luminescent Materials and Devices, South China University of Technology, Guangzhou 510641, China and Department of Electronic Materials, School of Materials Science and Engineering, South China University of Technology, Guangzhou 510641 (China)

Using low-temperature molecular beam epitaxy, amorphous In{sub 0.6}Ga{sub 0.4}As layers have been grown on GaAs substrates to act as buffer layers for the subsequent epitaxial growth of In{sub 0.3}Ga{sub 0.7}As films. It is revealed that the crystallinity of as-grown In{sub 0.3}Ga{sub 0.7}As films is strongly affected by the thickness of the large-mismatched amorphous In{sub 0.6}Ga{sub 0.4}As buffer layer. Given an optimized thickness of 2 nm, this amorphous In{sub 0.6}Ga{sub 0.4}As buffer layer can efficiently release the misfit strain between the In{sub 0.3}Ga{sub 0.7}As epi-layer and the GaAs substrate, trap the threading and misfit dislocations from propagating to the following In{sub 0.3}Ga{sub 0.7}As epi-layer, and reduce the surface fluctuation of the as-grown In{sub 0.3}Ga{sub 0.7}As, leading to a high-quality In{sub 0.3}Ga{sub 0.7}As film with competitive crystallinity to that grown on GaAs substrate using compositionally graded In{sub x}Ga{sub 1-x}As metamorphic buffer layers. Considering the complexity of the application of the conventional In{sub x}Ga{sub 1-x}As graded buffer layers, this work demonstrates a much simpler approach to achieve high-quality In{sub 0.3}Ga{sub 0.7}As film on GaAs substrate and, therefore, is of huge potential for the InGaAs-based high-efficiency photovoltaic industry.

• OSTI ID: 22280557
• Journal Information: Applied Physics Letters, Vol. 104, Issue 4; Other Information: (c) 2014 Author(s); Country of input: International Atomic Energy Agency (IAEA); ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ABSORPTION SPECTROSCOPY
DISLOCATIONS
ENERGY EFFICIENCY
FLUCTUATIONS
GALLIUM ARSENIDES
INDIUM ARSENIDES
LAYERS
MOLECULAR BEAM EPITAXY
PHOTOVOLTAIC EFFECT
STRAINS
SUBSTRATES
SUPERCONDUCTING FILMS
SURFACES
TEMPERATURE DEPENDENCE
X-RAY SPECTROSCOPY