Mathematical model of kinetics of charge deep levels in the forbidden band of the semiconductor, which takes into account the processes of carriers charge exchange between deep levels and both allowed bands, which adequately describes the nature of the non-exponential relaxation capacity, is proposed. A method for determining the spectrum of deep level transient spectroscopy having greater accuracy and resolution in comparison with traditional methods using a relaxation time approximation. The results of numerical experiments using the kinetics charge deep levels model in the frameworks of proposed approximations are presented. Account of generational and recombination components of charge exchange processes of all deep levels in the forbidden band of the semiconductor leads to the conclusion that the kinetics of ionization of these centers, in general, does not obey the Boltzmann statistics. Account of charge exchange processes between the deep levels a significantly effects on their recharge kinetics. Numerical analysis results show that the processes of deep levels ionization are more complicated than the staged-type kinetics. It is shown that in most cases stagedtype kinetics at deep level transient spectroscopy leads to significant methodological error in the parameters determination. From the results of numerical analysis follows, that the density of surface electronic states has a significant impact on the overall recharged kinetics of deep levels. Donor deep levels recharge analysis revealed not only the features of the deep levels ionization in semiconductors, but also allowed to answer some questions that are typical to all deep-level transient spectroscopy in general.

deep level, deep level transient spectroscopy, kinetics for ionizing the deep levels

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