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Various semiconductor devices created by molecular beam epitaxy and lithography were numerically modeled: a quantum point contact in the voltage gate-induced two-dimensional electron gas, a versatile tunable two-terminal quantum dot, a small three-terminal quantum dot, and ring interferometers. Three-dimensional electrostatics calculations, taking into account the design of structures, combined with the theories of Coulomb blockade and quantum ballistic transport, allowed explanation of the observed resistance features of nanodevices. Accumulated experience was used to design semiconductor artificial graphene. more...

In this chapter the ability to study atomic processes on the Si surface during sublimation, growth, oxygen etching, and gold adsorption by in situ ultrahigh vacuum reflection electron microscopy (a unique method developed in ISP SB RAS) are reviewed. Using this technique, a surface instability called the step-bunching phenomenon was discovered previously, it is however, still poorly understood due to many unknown parameters of adatom/advacancy step interactions. Observation of gold adsorption induced step-bunching depending on an annealing time at a temperature of T =900°C suggests that a surface-bulk defect exchange is also involved in the formation of instability. The dynamics of two-dimensional vacancy island formation on 120-µm step-free terraces shows that sublimation is defined by adatom detachment from steps up to a critical temperature of T crit ~1180°C, while adatom diffusion length falls from ~55 (970°C) to ~7 µm due to recombination with the vacancies. At T crit >1180°C, sublimation is dominated by the straightforward evaporation of surface atoms reserving vacancies that interact with steps. From the studies of Si growth on the step-bunched Si(111)-(7×7) surface, a crucial role of step permeability in 2D island nucleation and growth (2DNG) kinetics has been revealed. Step permeability is a key factor in pyramid-like growth on terraces exceeding the critical width for 2DNG. We show that quantitative parameters of adatom/vacancy diffusion and their interactions with steps (Schwobel barriers) can be determined. more...

“Step-and-terrace” surface morphology, with regular arrays of atomically flat terraces separated by monatomic steps was obtained by annealing GaAs(001) substrates in conditions close to equilibrium. The closeness of annealing conditions to equilibrium was determined by experiments on samples with lithographic marks. The annealing kinetics are characterized by full-length monatomic steps, and also by Fourier and autocorrelation analyses. A comparison of the experiment with Monte Carlo simulation enabled us to elucidate the main stages and microscopic mechanisms of the step-terraced morphology formation, and to evaluate the effective parameters which determined this process. The formation of straight dislocation-induced steps of monatomic height were studied under thermo-mechanical stress relaxation in GaAs/AlGaAs heterostructures bonded to glass. more...

The operating principles of subminiature semiconductor emitters are formulated in this chapter, and the research results of the performance for those emitters that have been developed and manufactured at the SB RAS Institute of Semiconductor Physics for the last 5 years are given. The results of developing single-mode vertical cavity surface emitting lasers with a wavelength of 795 nm future-oriented for application in a chip scale atomic clock operating at a transition of 5S1/2→5P1/2 of Rb87 atoms are reported, as well as the results of developing a fully semiconductor Bragg microcavity for single-photon emitters. The latter combines current pumping selectively positioned InAs quantum dots, high external quantum efficiency, and a low level of output radiation divergence. more...