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Arrays of coherent InSb quantum dots (QDs) have been fabricated by liquid-phase epitaxy on InAs substrates in the temperature range T = 420–450°C. The QDs with a density of (0.9−2) × 1010 cm−2 were 3 nm high and 13 nm in diameter. A bimodal QD size distribution was observed, which was accounted for by a combined growth mechanism of these nanoobjects. Structural characteristics of a separate InSb QD formed on the InAs surface were studied for the first time by atomic-force and transmission electron microscopies. Moire fringes were observed for the first time for QDs in the InSb/InAs system, with the moire period of 3.5 nm corresponding to InSb QDs without an admixture of arsenic. [ABSTRACT FROM AUTHOR]

Layers of the GaSb1 − x As x alloy with arsenic content in the range x = 0.06–0.15 have been grown for the first time on InAs (100) substrates by metal-organic vapor-phase epitaxy. A new approach to the calculation of the band diagram of the GaSbAs alloy is suggested. It is demonstrated on the basis of magnetotransport measurements in p-GaSbAs/ p-InAs heterostructures and with the method suggested by the authors for the calculation of band diagrams for alloys in the GaSbAs system that, in the composition range under study, the GaSbAs/InAs heterojunction is a type II broken-gap heterojunction. [ABSTRACT FROM AUTHOR]

The first original results on the growth of quantum dots (QDs) in the InSb/InAs system by liquid phase epitaxy (LPE) are reported. The density and dimensions of QDs were studied by methods of scanning probe microscopy and atomic force microscopy. The surface density, shapes, and dimensions of LPE-grown nanoislands depend on the growth conditions (temperature, cooling rate, and solution melt-substrate contact time). In the interval of temperatures T = 420–445°C, homogeneous arrays of InSb quantum dots on InAs(100) substrates were obtained with an average height of H = 3.4 ± 1nm, a radius of R = 27.2 ± 7.5 nm, and a density of up to 1.9 × 1010 cm−2. [ABSTRACT FROM AUTHOR]

High-quality type II Ga[sub 0.83]In[sub 0.17]As[sub 0.22]Sb[sub 0.78]/InAs heterostructures based on GaSb-rich quaternary solid solutions were grown by liquid phase epitaxy on InAs(001) substrates. GaInAsSb epilayers were grown under planar two-dimensional growth conditions with abrupt and planar interfaces. The thickness of the transition layer on the Ga[sub 0.83]In[sub 0.17]As[sub 0.22]Sb[sub 0.78]/InAs interface enriched with In and Sb was 10-12 Å in perfect structures. The roughness of the upper boundary was entirely determined by the epitaxial-growth conditions and did not exceed 500 Å in structures with a layer thickness of about 2 µm. [ABSTRACT FROM AUTHOR]

We report on the electroluminescent and I–V characteristics of the n-InAs/n-InAsSb/p-InAsSbP heterostructure grown by metalorganic vapor-phase epitaxy. In the spectral range of 0.23–0.29 eV, the high-intensity electroluminescence at a temperature of T = 77 K has been observed. The position of the maximum of the main emission band ( ~ 0.24 eV) has shown a noticeable blue shift with increasing forward bias. Based on the investigations, a conclusion about the existence of a type-II staggered heterojunction at the InAs0.84Sb0.16/InAs0.32Sb0.28P0.40 heterointerface has been drawn, which is confirmed by the calculated energy band diagram. [ABSTRACT FROM AUTHOR]

Asymmetric n-InAs/InAs(1 –y)Sby/p-InAsSbP heterostructures with a narrow-gap active layer and a composition range y = 0.09–0.16 were grown by vapor phase epitaxy from metalorganic compounds. Room-temperature electroluminescence was observed at a wavelength of up to λ = 5.1 μm at a spectral maximum. The study of low-temperature electroluminescence spectra provided the possibility to establish the existence of two radiative recombination channels caused by the nature of the InAsSb/InAsSbP heterointerface. The effect produced by the chemistry of the active layer on the composition of the grown barrier layer and the formation of the InAsSb/InAsSbP heterojunction with an increase in the antimony content in the InAsSb solid solution was demonstrated. [ABSTRACT FROM AUTHOR]

Uniform arrays of the InSb quantum dots with a surface density of nQD = 2 × 109 cm–2 were obtained by liquid phase epitaxy on a matrix layer based on a multicomponent InGaAsSb solid solution lattice-matched with the GaSb substrate. The change in the composition of the cationic part of the matrix by using the epitaxial matrix layer allowed to lower the temperature of the epitaxy to T = 430°C and determined the shape of a typical InSb quantum dot in the form of a truncated cone with average values of height h = 3 nm and diameter d = 30 nm, which corresponded to the aspect ratio L = h/d = 0.1. [ABSTRACT FROM AUTHOR]

The design and technology for the fabrication of an asymmetric stepped InAs/InAs1 –ySby/InAsSbP heterostructure with an ultimate InSb content (up to y = 0.17) in the narrow-gap active region by vapor-phase epitaxy from metal-organic compounds are developed. The electroluminescence characteristics of long-wavelength LEDs based on the proposed heterostructure, which emits in the spectral range of 4.6–5.3 μm, are studied. A linear decrease in the quantum efficiency of the electroluminescence with increasing InSb content in the active layer of the LEDs obtained is revealed. The advantage of using the asymmetric heterostructure for fabricating LEDs with a working wavelength of more than 4.5 μm is shown. [ABSTRACT FROM AUTHOR]

Epitaxial layers of phosphorus-rich InAs[sub 1-y-x]Sb[sub y]P[sub x] solid solutions were obtained by liquid phase epitaxy (LPE). The films with x = 0.32 were grown at 575°C on isoperiodic (100)InAs substrates. It is shown that the growth of InAsSbP layers from a phosphorus-rich liquid phase is accompanied by saturation of the phosphorus content in the solid state. InAsSbP-based diode heterostructures emitting in the 2.6-2.8 µm wavelength range were obtained, the output emission power of which is sufficient for detecting both natural and industrial gases in the atmosphere. [ABSTRACT FROM AUTHOR]

Magnetotransport properties of the narrow-gap In[sub x]Ga[sub 1-x]As[sub y]Sb[sub 1-y]/GaSb heterojunctions grown by liquid-phase epitaxy with various In content in the solid solution (x=0.85-0.95 and E[sub g] ≤ 0.4 eV) were studied. It is shown that, depending on the In content in these heterostructures, type II staggered-lineup (x = 0.85) or brokengap heterojunctions (x = 0.95) with high mobility in the electron channel at the interface (µ ... 20 000 cm²/(V s)) can be realized. For x = 0.92, depending on temperature, both types of heterojunctions were observed. Obtained results are in good agreement with the band energy diagram of the type II InGaAsSb/GaSb heterostructures under study. [ABSTRACT FROM AUTHOR]

The diagrams of melt-solid solution (fusibility curves) and solid solution (I)-solid solution (II) (surfaces of spinodal decomposition of solid solutions) phase equilibria in the fivecomponent system In-Ga-As-Sb-P (the solid solutions are isoperiodic to the GaSb and InAs substrates) are calculated. The concentration ranges of the isovalent substitution solid solutions In[sub x]Ga[sub 1-x]As[sub y]Sb[sub z]P[sub 1 - y - z], which are accessible for synthesis by liquid-phase epitaxy, are calculated. [ABSTRACT FROM AUTHOR]