Investigation of the surface state of semi-insulating gallium arsenide after high-temperature annealing

The distribution of chromium and silicon in near-surface domains of semi-insulating gallium arsenide after annealing at different temperatures is investigated by the secondary ion method. It is shown that the surface of the specimens investigated is concentrated with the elements mentioned as a result of the annealing, however, their distribution over the bulk is not monotonie in nature. A considerably greater thermal stability of the GaAs:Cr₂O₃ exists after annealing at 600°C relative to the processes being investigated as compared with GaAs:Cr. It is also shown that prior to annealing the output of Si and Cr ions from GaAs:Cr₂O₃ greatly exceeds the output of these atoms from GaAs:Cr, which is associated with the different degree of the coupling of these elements in the material mentioned.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 1, pp. 76–80, January, 1988.     

Hole injection and surface state effects at gallium arsenide electrodes

We report capacitance and luminescence measurements at gallium arsenide electrodes in 1 M H₂SO₄ electrolyte that indicate the injection of holes on cathodic polarization. The steady-state potential-current relations and photoeffects are reviewed critically. We show that the assumption of hole injection is equally plausible to that of electron extraction provided the surface recombination velocity is fast compared to the bulk diffusion and recombination process. In addition to the space charge there is a substantial surface charge of the type commonly observed at III–V semiconductor surfaces.     

Evaporation of atoms from femtosecond laser-heated gallium arsenide

The surface temperature of a GaAs crystal irradiated with 150 fs laser pulses is determined from the Maxwell velocity distribution of the evaporated atoms. The crystal is strongly superheated, and melting is observed to occur at a temperature 600–1000 K above the equilibrium melting point.     

Plasma reflection in gallium arsenide

Procedures recently proposed for determining electrophysical parameters of highly doped semiconductors from the IR reflection spectra are analyzed. The case of n-type GaAs is discussed. Optical and Hall measurements have been carried out for a few samples, and it has been found that the electron density determined from the optical measurements is in good agreement with the Hall values, while the mobilities may differ significantly. It is concluded that mechanical polishing causes problems.Translated from Izvestiya VUZ. Fizika, No. 10, pp. 65–69, October, 1969.     

Thermal oxidation of gallium arsenide

The experimental results of this study of the thermal oxidation of GaAs under atmospheric conditions and in dry oxygen over a temperature range of 400–530C are presented. It is shown that for temperatures in the range of 400–450C the oxide layers are formed according to a parabolic law while for temperatures in the range of 480–530C they are formed according to a linear law. An interesting dependence of the reflectivity of GaAs with an oxide layer on the thickness of this layer during the initial stage of the oxidation process is described, giving evidence of the complex structure of the layer formed.     

Ion doping of gallium arsenide

Conclusion The survey presented shows that despite the intensive study of the physical problems of ion implantation in GaAs, there is still a number of questions to investigate. Among them are: The role of anomalous diffusion and channeling in the formation of concentration profiles, the anomalous diffusion mechanism, the influence of radiation defects and residual impurities as well as the form of the coating, the interaction between impurities and defects under ion implantation, and the identification of radiation defects, A further study of the above-mentioned questions will permit extension of the application of the ion implantation method to obtain GaAs semiconductor instruments and realization of still unused possibilities of this powerful method of modern semiconductor technology.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 1, pp. 76–90, January, 1980.     

Oscillatory photoconductivity of gallium arsenide

The photoconductivity of GaAs in the energy range 1.5 –1.8 eV at 4.2 K exhibits two types of quantum oscillations: Landau oscillations for epitaxial material in high magnetic fields or LO phonon oscillations for high resistivity material. The purity and surface treatment of the samples seem to determine the type of oscillations observed.     

Phonon heat transport in gallium arsenide

The lifetimes of quantum excitations are directly related to the electron and phonon energy linewidths of a particular scattering event. Using the versatile double time thermodynamic Green’s function approach based on many-body theory, an ab-initio formulation of relaxation times of various contributing processes has been investigated with newer understanding in terms of the linewidths of electrons and phonons. The energy linewidth is found to be an extremely sensitive quantity in the transport phenomena of crystalline solids as a collection of large number of scattering processes, namely, boundary scattering, impurity scattering, multiphonon scattering, interference scattering, electron–phonon processes and resonance scattering. The lattice thermal conductivities of three samples of GaAs have been analysed on the basis of modified Callaway model and a fairly good agreement between theory and experimental observations has been reported.     

Heat-stimulated currents in semi-insulating gallium arsenide

The energy spectrum of charge carrier traps of semi-insulating n-type gallium arsenide has been investigated by the method of heat-stimulated currents and the parameters characterizing these traps have been estimated. Trap acceptor levels with energies 0.37, 0.41 and 0.17, 0.28, 0.32, 0.34, 0.38, 0.40 eV have been found for samples with the specific resistivity 2.7 · 10⁷ and 1.6 · 10⁸ · cm, respectively. The results obtained are well explained within the framework of the theory of a compensated semiconductor.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii Fizika, No. 11, pp. 22–26, November, 1971.The authors are grateful to A. P. Vyatkin, V. G. Voevodin, and E. V. Kozeev for kindly providing the gallium arsenide crystals and stimulating the research.     

Residual lattice absorption in gallium arsenide

The residual lattice absorption of GaAs in the three and four phonon regime is measured over a range of temperatures. The spectra reveal persistent structural features which are interpreted theoretically in terms of phonon density of states effects.     

半绝缘砷化镓单晶中碳微区分布的研究

通过AB腐蚀（由Abrahams和Buiocchi发明的腐蚀方法，简称AB腐蚀）、KOH腐蚀，经金相显微镜观察、透射电子显微镜能谱分析、电子探针x射线微区分析，对液封直拉法生长的非掺 半绝缘砷化镓单晶中碳的微区分布进行了分析研究.实验结果表明，碳的微区分布受单晶中 高密度位错网络结构的影响.高密度位错区，位错形成较小的胞状结构，且胞内不存在孤立 位错，碳在单个胞内呈U型分布；较低密度位错区，胞状结构直径较大，且胞内存在孤立位 错，碳在单个胞内呈W型分布. 关键词： 半绝缘砷化镓 胞状位错 碳受主