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The technology for production one and two-cascade power laser converters was presented in this paper. According to the measurement results of the grown samples, an efficiency of 34.5% was achieved. A promising design of a cascade photoelectric converter is proposed, in which the cascades are connected with using conduction channels based on GaP microcrystallites. [ABSTRACT FROM AUTHOR]

Utilizing performed research, photoelectric converters of narrow-band radiation (λ ≈ 1.0–1.3 μm) based on InGaAsP/InP heterostructures with an epitaxial p–n junction have been developed and created. Technological regimes that apply of for creating high-quality layers of quaternary InGaAsP solid solutions isoperiodic to indium phosphide in a wide range of compositions by liquid-phase epitaxy have been determined. [ABSTRACT FROM AUTHOR]

The results of studies of 7.5–8.0 μm range surface-emitting ring quantum-cascade lasers are presented. A second- order diffraction grating with a calculated coupling coefficient of ~9 cm–1 is formed on the entire surface of the ring cavity by focused ion beam milling. Surface-emitting lasing at room temperature near 7.75 μm with a threshold current density of ~8 kA/cm2 and an outer radius of the ring cavity of 202 μm is demonstrated. The results of studying the intensity distribution in the far-field near the normal to the surface showed the presence of two maxima. It is shown that the implemented coupling coefficient is not sufficient to ensure single-mode lasing in the studied ring quantum-cascade lasers. [ABSTRACT FROM AUTHOR]

The results of studies of ring quantum-cascade lasers with surface emission due to a second-order grating formed in the top cladding layers are presented. Surface emission near 7.85 μm with a low threshold current density (3.8 kA/cm2), in comparison with ridge quantum-cascade lasers of the same cavity length is demonstrated. The results of measurements of the intensity distribution of the near and far fields at different pumping levels are presented. The estimated value of the angle of beam extraction relative to the surface normal is in the range 5.7°–6.7°. [ABSTRACT FROM AUTHOR]

The possibility of controlling the composition of lateral nanowires by the method of growth under quasi-equilibrium conditions in a quasi-closed volume from indium, phosphorus, and arsenic vapors with Au catalyst in the "vapor-liquid-solid" mechanism has been demonstrated for the first time. It has been experimentally shown that the additional presence of arsenic in the indium-phosphorus source leads to the coalescence of catalytic gold droplets at the initial stage of the growth, which determines the further morphology and growth kinetics of nanostructures. An additional formation of indium phosphide nanostructures with a composition different from that of the main nanowires was found. The results of the studies expand the possibilities of the developed method for obtaining lateral nanowires on gallium arsenide substrates. [ABSTRACT FROM AUTHOR]

The results of studying a ring surface-emitting quantum-cascade laser with radiation emission through a textured layer formed in the layers of the upper cladding of the waveguide by ultrahigh-vacuum ion-beam milling are presented. The far-field profile shows that the radiation is emitted through windows with a textured layer in the range of angles ~63°–75° to the surface normal. [ABSTRACT FROM AUTHOR]

Changes in the structure and elemental composition of the surface of the epitaxy-ready InP(001) substrate in an As flux in ultrahigh vacuum are studied in situ by the reflection high-energy electron diffraction (RHEED) technique. It is shown that, during annealing of the oxide layer at the surface, an InP1 –xAsx layer is formed as a result of the substitution of phosphorus by arsenic. The dependence of the degree of substitution on the annealing temperature and time is established. The degree of the substitution of phosphorus by arsenic in the surface layer is 7% at the annealing temperature 480°C and, reaches 41% at the temperature 540°C. The annealing time influences the degree of substitution only slightly. [ABSTRACT FROM AUTHOR]

The electronic properties of n-InP(100) surfaces passivated with various sulfide solutions are studied using photoluminescence and Raman spectroscopy. It is shown that the passivation process leads to an increase in the photoluminescence intensity of the semiconductor, which indicates a decrease in the velocity of nonradiative surface recombination accompanied by a narrowing of the surface space-charge region and an increase in the electron density in the analyzed semiconductor bulk. The efficiency of electronic passivation of the n-InP(100) surface depends on the composition of the sulfide solution. [ABSTRACT FROM AUTHOR]

The generation of the second-harmonic radiation of a gyrotron with an operating frequency of 263 GHz due to second-order lattice nonlinearity in iron-doped indium-phosphide crystals is experimentally demonstrated. It is shown that second-harmonic radiation can be used in the magnetospectroscopy of semiconductor nanostructures. The possibility of generating the difference frequency in these crystals excited by two mid-IR sources with close wavelengths is discussed. [ABSTRACT FROM AUTHOR]

The effect of chemical passivation in solutions of ammonium sulfide (NH4)2S on the optical and electronic properties of the surface n-InP (001) is studied. It is shown that treatment in a 4% aqueous solution of (NH4)2S leads to a twofold decrease in the surface field and charges localized in this region. Treatment in a 4% alcohol solution (NH4)2S leads to a decrease in these parameters by a factor of 3, and, moreover, the barrier photovoltage decreases by a factor of 3. [ABSTRACT FROM AUTHOR]

Quantum-cascade lasers with surface emission of radiation by means of a grating formed in the upper waveguide cladding layers by ion-beam milling are fabricated and studied. The active region of the laser heterostructure is based on the In0.53Ga0.47As/Al0.48In0.52As alloy alloys and uses a design with two-phonon resonance emptying of the lower level in the cascade. Room-temperature lasing near 7.9 μm is demonstrated for a laser with a ring-cavity diameter of 191 μm. The mode spacing in the lasing spectra corresponds to whispering-gallery modes. [ABSTRACT FROM AUTHOR]

Passivation of the n-InP(100) surface with sodium sulfide (Na2S) aqueous solution is analyzed by photoluminescence (PL) and X-ray photoelectron spectroscopy (XPS). The room-temperature PL intensity increases essentially even after short treatment with sulfide solution for 1 min. The enhancement in the room-temperature PL intensity after passivation decreases with the increase in the bulk doping level of the semiconductor. Time-resolved PL studies performed at liquid-nitrogen temperature indicate reduction in the surface recombination velocity. This improvement of the PL intensity occurs just after transformation of the native oxide layer consisting mainly of indium phosphates to the passivating layer consisting of indium sulfides and oxides. The surface bands in n-InP(100) remained nearly flat both before and after sulfide passivation. [ABSTRACT FROM AUTHOR]

The impedance and capacitive properties of Pd/oxide/InP structures are investigated at 300 K in the frequency range of 10–1–10–5 Hz in air and in a nitrogen–hydrogen gas medium. The characteristics of structures in both media are interpreted based on a parallel RC-chain model with series resistance. The structure resistance decreases in the presence of hydrogen by three orders of magnitude, while the capacitance increases by 1–3 orders of magnitude depending on the frequency, which is possibly associated with the formation of positively charged centers in the oxide. Hysteresis is found in the capacitance–voltage characteristics in the medium with hydrogen, which is possibly caused by the ionic polarization of centers. It is shown that the total charge of centers measured in units of electrons almost coincides with the number of hydrogen atoms absorbed by palladium. [ABSTRACT FROM AUTHOR]

The possibility of obtaining intense terahertz radiation due to second-order lattice nonlinearity in indium-phosphide crystals doped with iron is discussed. As a source of radiation, subterahertz gyrotrons are considered. It is shown that the efficiency of frequency doubling can reach 3%, which opens up the possibility for developing a new generation of terahertz radiation sources. The possibility of applying second-harmonic radiation for the magnetospectroscopy of semiconductor structures with quasi-Dirac dispersion is demonstrated. [ABSTRACT FROM AUTHOR]

Abstract: The possibility in principle of the MBE (molecular-beam epitaxy) growth of GaP and InP nanowires on a SiC substrate with a graphene layer is demonstrated for the first time. InP nanowires on such a substrate have no stacking faults and possess an ideal crystallographic quality. At the same time, GaP nanowires have structural defects of the type of twins and the reversal of crystallographic phases at the top and at the base. The results of structural measurements demonstrate that the nanowires are formed in the wurtzite phase, which is not typical of bulk III-V materials. [ABSTRACT FROM AUTHOR]

Abstract: The photovoltage of a metal-insulator-semiconductor structure (Pd-anodic oxide-InP) is studied in relation to the hydrogen concentration in the range 0.1-100 vol % in a nitrogen-hydrogen gas mixture. It is shown that, under simultaneous exposure of the structure to light and hydrogen, the photovoltage decay rate and the hydrogen concentration are exponentially related to each other: NH = aexp(bS). Here, NH is the hydrogen concentration (vol %) in the nitrogen-hydrogen mixture. S = dU/dt|t = 0 is the rate at which the signal U changes in the initial portion of the photovoltage decay, beginning from the instant at which the structure is brought into contact with the gas mixture. a and b are constants dependent on the thicknesses of the palladium layer and anodic oxide film on InP. [ABSTRACT FROM AUTHOR]

The fabrication and study of the characteristics of a lattice-matched quantum cascade laser structure on an indium-phosphide substrate, designed for a wavelength of ~4.8 μm corresponding to one of the atmospheric windows are described. The heterostructure grown by molecular-beam epitaxy consisted of thirty cascades. Lasing was experimentally observed at temperatures up to 200 K at a wavelength coinciding with the calculated one, which confirms the high heterointerface quality and high precision of the layer thicknesses and active-region doping levels. [ABSTRACT FROM AUTHOR]

The electron-transport and optical properties of heterostructures with a surface InGaAs/InAlAs quantum well in the cases of inverted δ doping with Si atoms (below the quantum well) and of standard δ doping (above the quantum well) are compared. It is shown that, in the case of inverted doping, the two-dimensional electron density in the quantum well is increased in comparison with the case of the standard arrangement of the doping layer at identical compositions and thicknesses of other heterostructure layers. The experimentally observed features of low-temperature electron transport (Shubnikov-de Haas oscillations, Hall effect) and the photoluminescence spectra of heterostructures are interpreted by simulating the band structure. [ABSTRACT FROM AUTHOR]

InP (100) crystals implanted with Be ions with an energy of 100 keV and doses of 10-10 cm are studied by Raman spectroscopy before and after thermal annealing at temperatures of 300-850°C. It is found that, as the implanted ion dose is increased, the surface region of InP is partially amorphized; in this case, spectral lines related to longitudinal lattice vibrations exhibit a shift to lower frequencies and inhomogeneous broadening, which is indicative of the formation of a nanocrystalline phase. Thermal annealing results in recovery of the crystal structure of InP. At annealing temperatures of >700°C, scattering at phonon-plasmon coupled modes is detected in the Raman spectra. This is attributed to electrical activation of the impurity. From the frequency of the phonon-plasmon mode, the concentration of heavy holes is estimated in the context of the model of a two-oscillator dielectric function. [ABSTRACT FROM AUTHOR]

Semiconductor lasers based on MOCVD-grown AlGaInAs/InP separate-confinement heterostructures are studied. It is shown that raising only the energy-gap width of AlGaInAs-waveguides without the introduction of additional barriers results in more pronounced current leakage into the cladding layers. It is found that the introduction of additional barrier layers at the waveguide-cladding-layer interface blocks current leakage into the cladding layers, but results in an increase in the internal optical loss with increasing pump current. It is experimentally demonstrated that the introduction of blocking layers makes it possible to obtain maximum values of the internal quantum efficiency of stimulated emission (92%) and continuouswave output optical power (3.2 W) in semiconductor lasers in the eye-safe wavelength range (1400-1600 nm). [ABSTRACT FROM AUTHOR]

Pd-oxide-InP (MOS) structures are fabricated, and their physical and photoelectric properties in a hydrogen atmosphere are investigated. It is established that a decrease in photovoltage of the structure and a large increase in photocurrent in the circuit are observed under the pulsed effect of hydrogen on the structure with a palladium layer illuminated by a light-emitting diode (LED of the wavelength λ = 0.9 μm). The kinetics and mechanism of the variation in the photovoltage and photocurrent are considered. It is assumed that the photovoltage decreases because of the ionization of hydrogen atoms in the Pd layer, and the photocurrent increases due to the thermionic emission of nonequilibrium electrons from the Pd layer into the semiconductor. On the basis of results of the investigations, the sensitive element for an optoelectronic hydrogen sensor is developed. [ABSTRACT FROM AUTHOR]

The special postgrowth processing of structures for quantum-cascade lasers is studied. The processing includes regrowth with a high-resistivity material (indium phosphide) with a carrier concentration of n ≈ 5 × 10 cm, photolithography with various wet chemical etchants, and the fabrication of special contacts providing enhanced heat removal. The use of modified postgrowth processing provides necessary parameters satisfying requirements for high-quality devices. [ABSTRACT FROM AUTHOR]

In this article, the characteristics of InP/InGaAs heterostructure-emitter bipolar transistors with 30 n-InP layer tunneling layers and a five-period InP/InGaAs superlattice are demonstrated and comparatively investigated by experimentally results and analysis. In the three devices, a 200 Å n-InGaAs layer together with an n-InP tunneling emitter layer (or n-InP/ n-InGaAs superlattice) forms heterostructure emitter to decrease collector-emitter offset voltage. The results exhibits that the largest collector current and current gain are obtained for the tunneling transistor with a 30 Å n-InP tunneling emitter layer. On the other hand, some of holes injecting from base to emitter will be blocked at n-InP/ n-InGaAs heterojunction due to the relatively small hole transmission coefficient in superlattice device, which will result in a considerable base recombination current in the n-InGaAs layer. Therefore, the collector current and current gain of the superlattice device are the smallest values among of the devices. [ABSTRACT FROM AUTHOR]

Cyclotron resonance and magnetic transport in InP/InGaAs/InP heterostructures with axially symmetric quantum wells are studied experimentally at 4.2 K. An increase in the cyclotron mass at the Fermi level from 0.047 m to 0.057 m with an increase in the concentration of two-dimensional electrons from 5.5 × 10 to 2.1 × 10 cm is shown. The values of the Rashba spin splitting at the Fermi level are determined from Fourier analysis of the beats of Shubnikov-de Haas oscillations. The obtained experimental data are compared with the theoretical results of self-consistent calculations of the energy spectrum and cyclotron masses of 2D electrons performed using the eight-band k · p Hamiltonian. [ABSTRACT FROM AUTHOR]

In this article, the influence of InGaAsP spacers inserted at base-collector (B-C) junction in the InP/InGaAs double heterojunction bipolar transistors is demonstrated by two-dimensional semiconductor simulation. Due to the addition of an InGaAsP spacer layer, two small potential spikes are formed at B-C junction and the current blocking effect is reduced. The results exhibit that the maximum current gain increases from 30 to 374 (375) as the thickness of InGaAsP spacer layer varies from 0 to 100 Å (300 Å). On the other hand, the device with a thicker spacer layer (300 Å) could effectively improve the knee effect of the current-voltage curves as compared the other devices. In addition, the collector-emitter offset voltages less than 10 mV are observed in the three devices. [ABSTRACT FROM AUTHOR]

In this paper, the characteristics of InP/InGaAs abrupt, setback, and heterostructure-emitter heterojunction bipolar transistors (HBTs) are comparatively investigated by twodimensional simulation analysis. In the setback (heterostructure-emitter) HBT, a thin 50 Å undoped InGaAs ( n-InGaAs) layer is inserted between n-InP emitter and p-InGaAs base layers to lower the energy band at emitter side for decreasing the collector-emitter offset voltage. The simulated results exhibits that the abrupt HBT has the largest current gain, the largest collector-emitter offset voltage, and the smallest unity gain cutoff frequency. While, the setback and heterostructure-emitter HBTs exhibit the smallest current gain and offcet voltage, respectively. Consequentially, the demonstration and comparison of the three-type HBTs provide a promise for design in circuit applications. [ABSTRACT FROM AUTHOR]

The electrical-thermal-optical characteristics of AlGaInP yellow and InGaN/GaN blue LEDs under electrical stresses were studied. Since the increase of effective acceptor concentration on p-type side, the forward voltages of AlGaInP decrease after 3155 h aging. And the operating voltage of high forward bias expansion for InGaN/GaN is due to the increase of the series resistance. Compared with InGaN/GaN, AlGaInP LEDs display different trend for the relationship between optical output and ideality factors. The relationship between ideality factor and radiative recombination is also studied and established. The characteristic of different intermediate adhesive is compared during aging period based on transient thermal test. [ABSTRACT FROM AUTHOR]

The effect of the postgrowth annealing of InP/InAsP/InP heterostructural nanowires produced by molecular-beam epitaxy on their structural and optical properties is studied. It is shown that the procedure of short-term (1 min) annealing in an argon atmosphere provides a means for increasing the emission intensity of InAsP quantum dots, suppressing the emission from InAsP quantum wells formed as a result of lateral growth, and substantially reducing the density of structural defects in the nanowires. [ABSTRACT FROM AUTHOR]

Using scanning electron microscopy, the influence of dislocations on the mechanism of pore formation during electrolytic etching of single-crystal InP is shown. During studying of the nanostructure of porous layers, the features of mechanisms of pore formation in the n-InP samples are established. It is shown that they are caused by outcrop of dislocations on the (111) surface and pore growth both along the surface and perpendicularly to it. The dislocation density in the places of an increased impurity concentration is calculated. [ABSTRACT FROM AUTHOR]

The radiation resistance of Au-Pd-Ti-Pd- n-InP ohmic contacts and Au-TiB- n- n- n-InP barrier contacts-both initial and subjected to a rapid thermal annealing and irradiated with Co γ-ray photons with doses as high as 10 R-has been studied. Before and after external effects, the electrical characteristics of the barrier and ohmic contacts, distribution profiles for components, and phase composition in the metallization layers have been measured. In ohmic Pd-Ti-Pd-Au contacts subjected to rapid thermal annealing and irradiation, a significant distortion of the layered structure of metallization occurs; this distortion is caused by the thermal and irradiation-stimulated transport of Pd over the grain boundaries in polycrystalline Ti and Au films. However, the specific contact resistance ρ does not change appreciably, which is related to a comparatively unvaried composition of the contact-forming layer at the Pd- n-InP interface. In the initial sample and the sample subjected to the rapid thermal annealing at T = 400°C with the Au-TiB- n- n- n-InP barrier contacts and irradiated with the dose as high as 2 × 10 R, a layered structure of metallization is retained. After irradiation with the dose as high as 10 R, in the samples subjected to a rapid thermal annealing at T = 400°C, the layered structure of metallization becomes completely distorted; however, this structure is retained in the initial sample. The electrical properties of the contact structure appreciably degrade only after irradiation of the sample preliminarily subjected to a rapid thermal annealing at T = 400°C. [ABSTRACT FROM AUTHOR]

The dc performances of an InP/InGaAs pnp heterostructure-emitter bipolar transistor are investigated by theoretical analysis and experimental results. Though the valence band discontinuity at the InP/InGaAs heterojunction is relatively large, the addition of a heavily-doped as well as thin p +-InGaAs emitter layer between p-InP confinement and n +-InGaAs base layers effectively eliminates the potential spike at emitter-base junction and simultaneously lowers the emitter-collector offset voltage and increases the potential barrier for electrons. Experimentally, a high current gain of 88 and a low offset voltage of 54 mV have been achieved. [ABSTRACT FROM AUTHOR]

Monolithic dual-junction GaInP/GaAs solar cells grown by the MOCVD method were studied. The conditions of the growth of ternary Ga x In1− x P and Al x In1− x P alloys lattice-matched to GaAs are optimized. Technology for fabrication of a tunneling diode with a high peak current density of 207 A/cm2 on the basis of heavily doped n ++-GaAs:Si and p ++-AlGaAs:C layers is developed. Cascade GaInP/GaAs solar cells obtained as a result of relevant studies featuring a good efficiency of the solar-energy conversion both for space and terrestrial applications. The maximum value of the GaInP/GaAs solar-cell efficiency was 30.03% (at AM1.5D, 40 suns). [ABSTRACT FROM AUTHOR]

Electrical characteristics of Cr–n-InP and Mo–n-InP diode structures were investigated, and the charge-transport mechanism was estimated. It was established that this is either a thermionic or generation–recombination current that dominates in the Cr–n-InP structures, depending on temperature. In Mo–n-InP structures, the double injection of charge carriers dominates in the drift transport. © 2003 MAIK “Nauka / Interperiodica”. [ABSTRACT FROM AUTHOR]

Negative luminescence (NL) at λ[sub max] = 3.8 µm from reverse-biased p-InAsSbP/n-InAs diode hetero-structures has been studied at temperatures of 70-180°C. The NL power increases with temperature and exceeds the power of direct-bias electroluminescence at temperatures over 110°C. An NL power of 5 mW/cm², efficiency of 60%, and a conversion efficiency of 25 mW/(A cm²) have been obtained at 160°C. [ABSTRACT FROM AUTHOR]

Data on threshold currents, the differential quantum efficiency, the emission spectrum, current tuning, and radiation power of mesastripe InGaAsSb(Gd)/InAsSbP double heterostructure lasers with λ = 3.0-3.3 μm and a cavity length of 70-150 μm in a temperature range of 50-107 K are reported. In the experiments, the threshold currents I[sub th] < 10 mA, a total output power of 0.5 mW/facet, and a single-mode power of 0.43 mW at 77 K in the cw regime were obtained. Lasers operated in the single-mode regime at currents I ≤ 6I[sub th], the spectral purity was as high as 650: 1, the tuning rate was 210 cm[sup -1]/A, and the tuning range was 10 cm[sup -1] wide. An example of methane detection at 3028.75 cm[sup -1] is presented. [ABSTRACT FROM AUTHOR]

Wide-mesastripe InGaAsP/InP heterostructure lasers emitting at 1.3-1.5 μm were grown by metalorganic chemical vapor deposition (MOCVD). Radiation-power-current and spectral characteristics of the lasers have been studied in pulsed and continuous wave (cw) operation in the temperature range of 10-60°C. The temperature of the active region of the diode laser is higher by 30-60°C than that of the copper heatsink upon saturation of the cw output power. The temperature dependence of the differential quantum efficiency strongly affects the cw output power. Output powers of 3 and 2.6 W are achieved in mesastripe lasers in cw operation, and 9 and 6.5 W in pulsed operation, at wavelengths of 1.3 and 1.5 μm, respectively. [ABSTRACT FROM AUTHOR]

Electrical properties of single-crystal InP samples with various initial concentrations of charge carriers were studied in relation to the dose of irradiation with fast reactor neutrons and subsequent heat treatments in the temperature range of 20-900°C. It is shown that the behavior electrical properties depends on the doping level of the starting material and that the heat treatment in the aforementioned range of temperatures results in a complete elimination of radiation defects, which makes it possible to apply the method of nuclear-transmutation doping to InP samples. The contribution of nuclear reaction initiated by intermediate-energy neutrons to the total level of nuclear-transmutation doping amounts to about 10%. [ABSTRACT FROM AUTHOR]

Experimental results of studying the process of transmutation doping of InP single crystals by irradiating with nuclear-reactor neutrons are reported; the possibility of doping with tin in a wide range of concentrations and obtaining the concentration of free electrons as high as 2 x 10[sup 19] cm[sup -3] is demonstrated. Electrical properties of InP and their behavior under irradiation and in the course of subsequent heat treatments were studied. The prospects for utilization of the nuclear-transmutation method for doping are assessed. [ABSTRACT FROM AUTHOR]

InGaAsP epitaxial layers, which are obtained in the instability region on InP (001) and GaAs (001) substrates, are investigated by photoluminescence and transmission-electronmicroscopy methods. The results are discussed on the basis of the theory of spinodal decomposition of solid solutions. It is established experimentally that in certain temperature and composition ranges the solid solutions InGaAsP are a system of charged, alternating (in mutually perpendicular directions [100] and [010]) domains of a solid solution with two different compositions and different lattice constants. The domain structure is very clearly defined at the surface of the epitaxial film and becomes blurred in the film near the substrate. The data obtained very likely show spinodal decomposition of the solid solutions InGaAsP in the test samples. [ABSTRACT FROM AUTHOR]

X-ray photoelectron spectroscopy, the Kelvin probe method, and Raman scattering are used to study the properties of the surface of n-type InP (100) passivated by ammonium sulfide dissolved in water or in t-butyl alcohol. Both treatments are found to cause a reduction in the depth of the depleted skin layer, a shift of the surface Fermi level toward the conduction band, and an enhancement of the electron work function and increase in the ionization energy of the semiconductor. The processing in the alcohol solution yields a stronger effect than processing in an aqueous solution. For sulfidization in an alcohol solution the surface Fermi level shifts by 0.2 eV, while the ionization energy increases by 0.53 eV. [ABSTRACT FROM AUTHOR]

The influence of mismatch stress on the structural, optical, and transport properties of thick InGaAs layers grown on InP(100) substrates by molecular-beam epitaxy is investigated. It is found that layers having tensile stress can be grown with a greater mismatch than compressively stressed layers before plastic relaxation sets in. The critical mismatch for thick InGaAs layers is not described with sufficient accuracy by either the mechanical equilibrium model or the energy balance model. The range of mismatches required to obtain high carrier mobilities and high radiative recombination efficiencies in InGaAs layers grown on InP substrates is much narrower than the pseudomorphic growth range. The maximum mobilities and minimum widths of the photoluminescence peak are attained in layers matched with the substrate in terms of the lattice parameter and also in slightly gallium-enriched layers. The compositional dependence of the width of the band gap is investigated with allowance for the influence of stress. © 1997 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The intrinsic photoconductivity of copper-compensated indium phosphide has been studied. It is found that mechanical polishing of a sample surface gives rise to an additional photoconductivity peak in the region of the fundamental absorption edge. This peak disappears upon storage of the sample. The dependence of the shape of the photoconductivity spectrum on the storage time, electric-field strength, and position of the light spot with respect to the contacts was determined. The results are explained in terms of variation in the lifetime of nonequilibrium carriers across the sample thickness. An expression qualitatively describing the photoconductivity spectra is presented. [ABSTRACT FROM AUTHOR]

Measurements have been made of the photosensitivity of (p[sup +]-p[sup -])-InP/n[sup +]-CdS structures formed by the growth of indium phosphide and cadmium sulfide films on p[sup +]-InP substrates with (100) crystallographic orientation. These structures exhibit a photosensitivity S[sub i]...0.13A/W in the spectral range from 1.3 to 2.4 eV at T=300 K. Polarizational photosensitivity was observed for oblique incidence of linearly polarized light on the CdS surface of these structures. The induced photopleochroism of these structures is governed by the angle of incidence θ. The photopleochroism increases proportionally to θ² and its maximum value is found to be ∼50% at θ...75-80°. The maximum azimuthal photosensitivity was found to be ∼0.13A/W-deg. Structures consisting of CdS deposited on InP can be used as polarimetric photodetectors. [ABSTRACT FROM AUTHOR]