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MOCVD growth and characterization of InAs-rich GaInAsSb on GaSb substrates was investigated. High quality mirror-like surfaces with a minimum lattice mismatch of 0.4% was obtained. The surface of InAs-rich GaInAsSb epilayer shows morphological features much different from that of GaSb-rich films. Solid compositions of InAs-rich films were dependent on growth temperature. InAs-rich GaInAsSb shows n-type conduction, which is the opposite of GaSb-rich samples. A room temperature electron mobility of 5000 cm(2)/V.s with electron concentration of 3.6 x 10(17) cm(-3) was obtained. (C) 1998 Elsevier Science B.V. All rights reserved.

The quaternary Ga 0.16 In 0.84 As 0.80 Sb 0.20 epilayer was grown on GaSb substrate by metalorganic chemical vapour deposition (MOCVD). On the epitaxial surface smooth and perfect three-dimensional islands were observed by atomic force microscopy (AFM). A good crystalline quality was characterized by single-crystal X-ray diffraction pattern and double-crystal X-ray rocking curve. When the growth rate of the growth nucleus is larger than the growth rate of the high-index facet, the mode of island growth is isotropic.

GaInAsSb alloys were grown by atmospheric pressure metalorganic chemical vapour deposition (MOCVD) on n-GaSb (Te-doped) substrates, oriented 2°–3° off (100) towards 〈110〉. The surface morphology of Sb-related III–V compounds depends on the growth parameters, the lattice mismatch and the quality and orientation of the surface of the substrate. The defect growth process is observed by scanning electron microscopy (SEM) and scanning electron acoustic microscopy (SEAM). The Ga and Sb concentrations in the solid were characterized as a function of the input ratio of Sb to group V, the AsH3 molar flow rate and growth temperature. On the other hand, the growth efficiency has been studied versus the AsH3 molar flow and growth temperature. The crystalline quality of the GaInAsSb epilayer has been characterized by the single-crystal X-ray diffraction pattern and double-crystal X-ray rocking curve diffraction.

Metalorganic chemical vapor deposition (MOCVD) of ternary GaxIn1−xSb alloys on GaSb and GaAs substrates has been investigated at atmospheric pressure, using TMGa, TMIn and TMSb as source materials. The optimized growth parameters obtained by experiment were a growth temperature of 600°C and a vapor IIIV ratio of 0.4. It was found that the growth temperature was a key growth parameter for surface morphology and crystalline quality of the GaxIn1−xSb epilayer. The influence of the growth temperature on the Ga solid composition was previously explained. The Ga solid composition was proportional to the Ga vapor composition and vapor IIIV ratio, respectively. The Ga distribution coefficient was found to be 1.06 under the optimized growth parameters and decreased with decreasing growth temperature. The results of the Hall measurement for GaxIn1−xSb alloys were presented with p-type background of the epilayers.