Optical and structural properties of molecular-beam epitaxial GaAs on sapphire

Technical Report · Sat Apr 01 04:00:00 EST 1989

OSTI ID:5551111

Chin, A; Bhattacharya, P; Chang, K H; Biswas, D

The structural and optical properties of GaAs grown by molecular-beam epitaxy on (0001) and (01{bar 1}2)-oriented sapphire substrates are evaluated for possible direct deposition on sapphire optical fibers and optoelectronic device applications. X-ray diffraction studies and cross-sectional transmission electron-microscopy measurements show that the GaAs films are single-crystal and have a (111) orientation for both substrate orientations. Both x-ray and temperature-dependent photoluminescence measurements indicate that the quality of the GaAs films is better for the (01{bar 1}2) sapphire orientation. The incorporation of a graded-band-gap strained layer in InGaAs/GaAs superlattice near the sapphire-GaAs interface also improves the optical quality of the GaAs films. Low-temperature photoluminescence spectra is dominated by a peak at 1.49-1.495 eV, with a best linewidth of 26.9 meV, which is due to an integration of several impurity- and defect-related bound-exciton transitions. A peak-to-lower energies by about 60 meV is thought to be due to acceptor-like impurity defect complexes. Post-growth short-term halogen lamp annealing marginally improves the overall luminescence intensity of the samples. A linewidth of 20 meV is measured for a (80 A) GaAs/(120A)Al(0.3)Ga(0.7)As multiquantum grown on sapphire. It is apparent that device-quality single-crystal GaAs and GaAs-related compounds can be deposited directly on sapphire substrates by molecular beam epitaxy, using special growth techniques.

• Research Organization: Michigan Univ., Ann Arbor, MI (USA). Solid-State Electronics Lab.
• OSTI ID: 5551111
• Report Number(s): AD-A-209430/8/XAB
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360603 -- Materials-- Properties
42 ENGINEERING
420800* -- Engineering-- Electronic Circuits & Devices-- (-1989)
ALUMINIUM COMPOUNDS
ALUMINIUM OXIDES
ARSENIC COMPOUNDS
ARSENIDES
CHALCOGENIDES
CORUNDUM
CRYSTAL LATTICES
CRYSTAL STRUCTURE
DEPOSITION
EPITAXY
FIBER OPTICS
FILMS
GALLIUM ARSENIDES
GALLIUM COMPOUNDS
IMPURITIES
LUMINESCENCE
MECHANICAL PROPERTIES
MINERALS
MOLECULAR BEAM EPITAXY
OPTICAL PROPERTIES
ORIENTATION
OXIDE MINERALS
OXIDES
OXYGEN COMPOUNDS
PHOTOLUMINESCENCE
PHYSICAL PROPERTIES
PNICTIDES
SAPPHIRE
SPECTRA
SUBSTRATES
SUPERLATTICES