The result of the studies of dislocation luminescence in SiC crystals are presented in the report. This semiconductor forms great number of polytypes which differs by periodical alternation of cubic and hexagonal layers in basic planes. High probability of periodic pack infringement caused by very little energy of stacking fault leads to variation of dislocation structures in different glide planes of this crystals. Shockly and Frank partial dislocations are sufficiently important.The dislocation luminescence as growth origin so as dislocations included in result of plastic deformation or high temperature annealing. In this case the spectra of dislocation luminescence are the indicators of processes of phase transitions. The influence of impurities on the dislocation luminescence centers is investigated. The models of structure of dislocation centers and the mechanism of radiative transitions are proposed.

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Phase transformations of SiC crystals with grown original defects and thin films have been presented. The SiC crystals were grown by the Tairov method and the films were obtained by the “sandwich” and Chemical Vapor Deposition (CVD) methods. The analysis of absorption spectra, excitation spectra and low-temperature photoluminescence spectra testifies to the formation of a new microphase during the growth. The complex spectrum can be decomposed into similar structure-constituting spectra shifted on the energy scale relative to the former. Such spectra are indicators of the formation of new nanophases. The joint consideration of photoluminescence spectra, excitement photoluminescence spectra and absorption spectra testifies to the uniformity of different spectra and the autonomy of each of them. Structurally, the total complexity spectra correlate with the degree of disorder (imperfection) of the crystal and are related to the peculiarities of a defective performance such as a one-dimensional disorder. Three different types of spectra have three different principles of construction and behavior.

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The fundamental concept in the science of dislocations is the study of the optical properties of semiconductors. The purpose of this work is to investigate the dependence of the structural features of the low-temperature photo luminescence (LTPL) spectra with the lattice parameters of wideband semiconductors and binary materials. A decoding method of the LTPL spectra of the binary polytypic structures of SiC was used. As a result, we introduce here for the first time a new i-unit atomic parameter of energy scale for the LTPL spectra of binary polytypic nanostructures. The i-unit parameter equals 4.3 meV, i.e. which equals 1/2 of the distance between adjacent Si-C layers and gives the exact multiples of the basic spectral parameters to tenths of meV. The i-unit of energy scale allows the simplifying method of spectral analysis of fine structures in SiC polytypes. The proposed new atomic i-scale allows us to monitor the processes of phase transformations up to 0.0787 Å. This allows observing the displacement in tetrahedron of silicon and carbon with dimensions 7.56 Å. The introduction of a new energy parameter makes it possible to control the displacement and position of atoms with very high accuracy, which in turn is very important for understanding the nature of defects in semiconductors. It is shown that phase transformations in SiC are related to dislocation in the crystal and implemented by the deformation and diffusion mechanisms. Due to results the diagram of the interlayer scheme radiative recombination with resulting dislocation levels was introduced.