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В. О. Харченко, Д. О. Харченко, І. О. Лисенко, С. В. Кохан, В. В. Яновський, А. В. Дворниченко
«Моделювання процесів формування пірамідальних структур при епітаксіяльному рості»
577–626 (2015)

PACS numbers: 05.10.Gg, 05.40.-a, 05.45.Df, 81.15.Aa, 81.15.Hi, 81.16.Rf, 82.40.Np

We study processes of pyramidal-structures’ formation during epitaxial growth within the framework of the phase-field theory by taking into account interactions of adsorbate. In the case of constant surface temperature, fluctuations of the total flux of adsorbate are introduced. As shown, the pyramidal structures can be formed at elevated values of interaction energy for adsorbate. Dependences of the lateral correlation length on the control parameters are computed. As found, an increase in the multiplicative-noise intensity leads to formation of patterns with a needle-like structure. As shown within the framework of the generalized phase-field model by taking into account local change in the surface temperature during adsorption–desorption processes, at early stages of the system evolution, the oscillation regime of pattern formation is realized. As revealed, the frequency of temperature oscillations increases with the deposition-rate growth. As found within the generalized model, pyramidal structures are characterized by large differences in heights between two neighbour terraces and can be formed at low values of interaction energy for adsorbate. Surface growth indicator and roughness exponents are obtained. As determined, the mean number of adsorbate islands grows in time by the power law, and the mean area of pyramidal structures falls down in time by the power law with the same absolute value of exponent. Distributions of adsorbate islands over sizes are studied in detail. An estimation of the mean linear size of adsorbate clusters gives ? 100–400 nm. Within the framework of the generalized kinetic approach, a theoretical model for the island-size dynamics manifesting the self-similar behaviour and universality of the probability density over the island sizes is proposed.