Electrophysical properties of heat-treated gallium arsenide

The electrical conductivity, Hall effect, ionization energy, and defect concentration of GaAs samples subjected to various forms of heat treatment were studied. The original material comprised single crystals grown by the Bridgman and Czochralski methods with electron concentrations of 2·10¹⁵–7·10¹⁷ cm^–3. The ionization energy and defect concentration were calculated with an electronic computer. The thermal conversion of GaAs was attributed to traces of copper, lattice defects, and residual impurities. The mobility varied in a complicated manner with the temperature of heat treatment in GaAs samples retaining their original n-type conductivity.Translated from Izvestiya VU Z, Fizika, No. 3, pp. 69–76, March, 1973.     

Electrophysical properties of doped epitaxial CdSe films

The electrophysical properties of epitaxial films of cadmium selenide doped with zinc or gallium are investigated. It is shown that in doped films intercrystalline barriers are absent, and the mechanism of electron scattering is close to the scattering mechanism in single crystals. It is suggested that the removal of the intercrystalline energy barrier is due to localization of part of the activator at intercrystallite boundaries and neutralization of acceptor states in neutral complexes. The difference between the doping effect of zinc and gallium is shown.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 3, pp. 52–56, March, 1977.     

Electrophysical properties of metallic wire photonic crystals

Simple nonintersecting thin metallic wire photonic crystals are studied using the integral equation method based on the Green’s function for periodically arranged sources. A wavenumber- and wavevector-dependent effective permittivity tensor is derived upon homogenization, and the band diagram and the per-mittivity for the lower dispersion branch are calculated.     

Electrophysical properties of dielectric films in MDM-structures

Using the methods of reactive cathode sputtering in a low-voltage, penning-discharge installation, dielectric films from silica, silicon nitride, aluminum nitride, etc. are obtained. Parameters of the films in MDM structures, their optical properties and porosity are investigated as a function of the deposition rate, substrate temperature and reaction gas pressure. It is found out that the films from silicon nitride exhibit the highest dielectric strength and those from silicon dioxide show the least dielectric loss.     

Electrophysical properties of six-component ZTS-based ferrosoft ceramic

The properties of six-component ZTS-based ferrosoft ceramic are studied. The ceramic is found to exhibit properties of a ferroelectric relaxor. The R3c → R3m rhombohedral phase transition is observed in the ferroelectric phase of this composite. Polarization of samples with a constant electric field upon cooling through the Curie point enlarges the temperature range of the R3m phase’s existence, compared to roomtemperature polarization.     

Critical properties of a three-dimensional p-spin model

In this paper we study the critical properties of a finite dimensional generalization of the p-spin model. We find evidence that in dimension three, contrary to its mean field limit, the glass transition is associated to a diverging susceptibility (and correlation length). Received 13 May 1998     

Electrophysical properties of calcium at high pressures and temperatures

Electrical resistivity of two crystal phases of shock-compressed calcium and its melt was measured in a range of high pressures (10–50 GPa) and temperatures (800–1600 K). The thermodynamic equilibrium curves were constructed for different calcium phases and the shape of Hugoniot adiabat was determined in the region where it intersects the equilibrium curves. It is shown that sharp kinks observed earlier in the Hugoniot adiabat in shock experiments were caused not by the jumplike electronic transitions but by the intersections of the adiabat and the phase-equilibrium and melting curves. The electronic spectra of the calcium crystal phases were calculated using the electron-density functional method; the computational results are used to explain the observed behavior of the Ca resistivity under compression.     

Critical properties of the three-dimensional Ising model with quenched disorder

The static critical properties of the three-dimensional Ising model with quenched disorder are studied by the Monte-Carlo (MC) method on a simple cubic lattice, in which the quenched disorder is distributed as nonmagnetic impurities by the canonical manner. The calculations are carried out for systems with periodic boundary conditions and spin concentrations p=1.0; 0.95; 0.9; 0.8; 0.7; 0.6. The systems of non-linear sizes L×L×L, L=20-60 are researched. On the basis of the finite-size scaling (FSS) theory, the static critical exponents of specific heat α, susceptibility γ, magnetization β, and an exponent of the correlation radius in a studied interval of concentrations p are calculated. It is shown that the three-dimensional Ising model with quenched disorder has two regimes of the critical behavior universality in a dependence on nonmagnetic impurities.     

Electrophysical properties and electronic structure of tin-doped antimony telluride

The effect of Sn atoms on the electrophysical properties and x-ray photoelectron spectra of Czochralski-grown Sb₂Te₃ single crystals is studied. The character of the temperature dependences of the kinetic coefficients is shown to depend noticeably on the structure of the valence band, which consists of two valence subbands. Estimates of the effective density-of-states masses of holes and of the gap between the valence-band extrema in Sb₂Te₃: Sn agree with the data available for the Sb₂Te₃ not doped with tin. X-ray photoelectron spectra of Sb₂Te₃: Sn single crystals do not exhibit noticeable core-level shifts and electron density redistribution in the valence band.     

Electrophysical properties and energetical spectrum of heteroepitaxial germanium films

An epitaxial growth of Ge films from molecular beam is characterized by thermodynamical nonequilibrium. This leads to formation of numerous structural defects connected with local levels in the band gap (mainly acceptor-type). Depending on the deposition temperature the density of such levels may change in wide range (10¹⁶–10¹⁸ cm^?3). This determines various mechanisms of impurity conduction. The tails of the density of states in the band gap are also connected with the defect structure of the films. Stresses in heteroepitaxial Ge films result in the splitting of the valence band atk = 0 and in a change of the band gap. Thus, these stresses have influence on the electrical and optical properties of the films.     

Investigation of the critical properties of the three-dimensional weakly diluted potts model

The problem of the type of the phase transition in the three-dimensional weakly diluted Potts model with the number of spin states q= 3 has been investigated by the Monte Carlo method. The temperature dependences of the Binder cumulants, energy, magnetization, specific heat, and susceptibility have been calculated. It is found that the second-order phase transition occurs in a system at the spin concentration p = 0.9. The critical exponents of the magnetization (β), specific heat (α), and susceptibility (γ) and the critical correlation-length exponent v were calculated on the basis of the finite-size scaling theory at p = 0.9.     

Ergodic properties of the multidimensional rayleigh gas with a semipermeable barrier

We consider a multidimensional system consisting of a particle of massM and radiusr (molecule), surrounded by an infinite ideal gas of point particles of massm (atoms). The molecule is confined to the unit ball and interacts with its boundary (barrier) via elastic collision, while the atoms are not affected by the boundary. We obtain convergence to equilibrium for the molecule from almost every initial distribution on its position and velocity. Furthermore, we prove that the infinite composite system of the molecule and the atoms is Bernoulli.     

Electrophysical properties of InSb irradiated by electrons at 300 K

Results of a comparative investigation of InSb crystals irradiated by electrons (1 MeV, 300 K), doped metallurgically (Te, Zn) and by nuclear transformation (Sn), are presented. It is found that as a result of irradiation the Fermi level shifts to a position near (E_c - 0.03) eV (at 77 K), independently of the material type. Subsequent annealing of the irradiated crystals revealed an n-p-n-p conductivity-type conversion in weakly doped n-InSb and an n-p conversion in strongly doped n-InSb.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 7, pp. 99–103, July, 1991.     

Electrophysical properties of epitaxial gallium arsenide doped with acceptor impurities

Epitaxial layers of gallium arsenide doped with zinc and cadmium were grown in a chloride vapor-transport system using diethylzinc and dimethylcadmium as the sources of the impurity. We studied the effect of the inlet pressure of the impurities and the growth temperature on the doping level of the layers. We investigated the temperature dependences of the hole concentration and mobility in layers doped with zinc and cadmium up to different levels.V. D. Kuznetsov Siberian Physicotechnical Institute, Tomsk State University. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 2, pp. 54–58, February, 1995.     

Electrophysical properties of zinc-sulfide films obtained by high-frequency magnetron sputtering

The structure and electrophysical properties of zinc-sulfide films obtained by high-frequency magnetron sputtering are investigated. It is shown that the electrical strength of the films is no less than 10⁶ V·cnr^–1, the width of the forbidden band is 3.2–3.3 eV, and the refractive index is 1.8. The films are tested as electroluminescent layers in thin-film electroluminescent emitters. Luminescence with a brightness of 150 cd/m² is obtained.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 6, pp. 29–32, June, 1990.It remains to thank A. A. Miller for perfecting the electron-microscope investigations.     

Critical properties of the three-dimensional frustrated Ising model on a cubic lattice

The critical properties of the three-dimensional fully frustrated Ising model on a cubic lattice are investigated by the Monte Carlo method. The critical exponents α (heat capacity), γ (susceptibility), β (magnetization), and ν (correlation length), as well as the Fisher exponent η, are calculated in the framework of the finite-size scaling theory. It is demonstrated that the three-dimensional frustrated Ising model on a cubic lattice forms a new universality class of the critical behavior.     

Electrophysical properties of anode oxide films on an indium antimonide surface

Anode oxide films are widely used for the passivation of the surface of semiconductors of group A^IIIB^V (GaAs [1–5], InSb [6–8], InAs [9], etc.) and as a subgate dielectric in MOS devices on a base of these materials. As well as a study of the properties of the boundary of separation of an anode oxide-semiconductor, the investigation of the electrophysical properties of such anode oxide films is an independent and extremely important problem. This is due to the fact that such characteristics of MOS devices as the charge stability, hysteresis phenomena, leakage currents through the gate, etc., are largely determined by the volume properties of the dielectric layer (by the spectrum of localized electron states in the volume, the mechanism of charge transfer through the dielectric film, etc.). At the same time, much less attention has been paid to the study of the properties of anode oxide films than to the investigations of the boundary of separation of a dielectric and a semiconductor. In this paper we investigate the electrophysical properties of anode oxide films of indium antimonide obtained by anode oxidation of a semiconductor substrate in a 0.1 N aqueous solution of KOH. We measured the dependence of the capacitance of the anode oxide on frequency (f), on temperature (T), and on the bias voltage (V), as well as the DC current-voltage characteristics.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 4, pp. 79–83, April, 1981.