Galina Zayats - Academia.edu (original) (raw)
Papers by Galina Zayats
American Journal of Nano Research and Applications, 2017
We describe space-time evolution of electric charge induced in dielectric layer of simulated meta... more We describe space-time evolution of electric charge induced in dielectric layer of simulated metal-insulatorsemiconductor structures produced by irradiation with X-rays. The purpose of this article is to develop a model which most fully describes the phenomena occurring under the ionizing irradiation of MOS structures. For this, in addition to known processes, such as a generation of the electron-hole pairs in the dielectric volume, diffusion and drift in the electric field of mobile charge carriers (electrons and holes), capture holes at the traps and recombination of electrons with the trapped holes, we also took into account the formation of surface states. The mathematical model considered includes the continuity equations for free electrons and holes, the Poisson equation, the equation describing the kinetics of hole-charge accumulation at trap levels, and the equation describing the tunneling mechanism of discharge of the charge accumulated in the dielectric. The model developed makes it possible to simulate the processes of charge degradation of silicon structures by the effect of ionizing radiation, and to determine the change in the threshold voltage of the MIS structure under irradiation, the distribution of free and trapped charges in the dielectric, and the distribution of the electric field strength. The type of dose dependence of the change in the threshold voltage of the MIS structure is determined by a number of parameters: the concentration of the traps in the oxide, their distribution over the oxide thickness, the mobility and capture cross sections for electrons and holes, the nature of dependence of these parameters on the electric field in the oxide. The system of equations is solved iteratively by efficient numerical method. The obtained simulation results are in good agreement with the corresponding data presented in other scientific publications.
Journal of Electromagnetic Analysis and Applications, 2018
A coordinated physicomathematical model for the propagation of a soliton-like electromagnetic pul... more A coordinated physicomathematical model for the propagation of a soliton-like electromagnetic pulse in a heterogeneous medium is developed in the presence of strong discontinuities in the electromagnetic field. The model is based on the reduction of Maxwell's equations to the well-studied wave equation. When the electromagnetic pulse was specified, its amplitude modulation was taken into account, as was the nonstationary broadening of the spectral line. Conditions for matching the momentum for the first initial boundary-value problem are obtained. The time dispersion of the electrical induction is taken into account in terms of the function of signal conditioning which takes account of the broadening of its spectral line and integration over the continuous spectrum. With this approach, it is not necessary to neglect spatial derivatives, and also to use spatial nonlocal relations to take account of the effect of surface charge, surface current, and spatial dispersion of electrical induction at the interfaces of adjacent media.
Journal of Electromagnetic Analysis and Applications, 2019
A consistent physical and mathematical model of the propagation of electromagnetic waves in an in... more A consistent physical and mathematical model of the propagation of electromagnetic waves in an inhomogeneous medium with strong discontinuities of the electromagnetic field at the interface of two media, which is a rough surface, was developed. Mathematical modeling of rough surfaces and their profiles was carried out using fractal geometry, which allows us to display the topology of the object as close as possible to reality. For real heterogeneous rough structures, we have developed a through-counting method that takes into account the continuity of the total current at the interfaces of adjacent media, the effect of induced surface charge and surface current. This approach lets one avoid the necessity to set surface impedances depending on the structure of the field being determined and on the material properties.
SSRN Electronic Journal, 2022
American Journal of Nano Research and Applications, 2017
We describe space-time evolution of electric charge induced in dielectric layer of simulated meta... more We describe space-time evolution of electric charge induced in dielectric layer of simulated metal-insulatorsemiconductor structures produced by irradiation with X-rays. The purpose of this article is to develop a model which most fully describes the phenomena occurring under the ionizing irradiation of MOS structures. For this, in addition to known processes, such as a generation of the electron-hole pairs in the dielectric volume, diffusion and drift in the electric field of mobile charge carriers (electrons and holes), capture holes at the traps and recombination of electrons with the trapped holes, we also took into account the formation of surface states. The mathematical model considered includes the continuity equations for free electrons and holes, the Poisson equation, the equation describing the kinetics of hole-charge accumulation at trap levels, and the equation describing the tunneling mechanism of discharge of the charge accumulated in the dielectric. The model developed makes it possible to simulate the processes of charge degradation of silicon structures by the effect of ionizing radiation, and to determine the change in the threshold voltage of the MIS structure under irradiation, the distribution of free and trapped charges in the dielectric, and the distribution of the electric field strength. The type of dose dependence of the change in the threshold voltage of the MIS structure is determined by a number of parameters: the concentration of the traps in the oxide, their distribution over the oxide thickness, the mobility and capture cross sections for electrons and holes, the nature of dependence of these parameters on the electric field in the oxide. The system of equations is solved iteratively by efficient numerical method. The obtained simulation results are in good agreement with the corresponding data presented in other scientific publications.
Journal of Electromagnetic Analysis and Applications, 2018
A coordinated physicomathematical model for the propagation of a soliton-like electromagnetic pul... more A coordinated physicomathematical model for the propagation of a soliton-like electromagnetic pulse in a heterogeneous medium is developed in the presence of strong discontinuities in the electromagnetic field. The model is based on the reduction of Maxwell's equations to the well-studied wave equation. When the electromagnetic pulse was specified, its amplitude modulation was taken into account, as was the nonstationary broadening of the spectral line. Conditions for matching the momentum for the first initial boundary-value problem are obtained. The time dispersion of the electrical induction is taken into account in terms of the function of signal conditioning which takes account of the broadening of its spectral line and integration over the continuous spectrum. With this approach, it is not necessary to neglect spatial derivatives, and also to use spatial nonlocal relations to take account of the effect of surface charge, surface current, and spatial dispersion of electrical induction at the interfaces of adjacent media.
Journal of Electromagnetic Analysis and Applications, 2019
A consistent physical and mathematical model of the propagation of electromagnetic waves in an in... more A consistent physical and mathematical model of the propagation of electromagnetic waves in an inhomogeneous medium with strong discontinuities of the electromagnetic field at the interface of two media, which is a rough surface, was developed. Mathematical modeling of rough surfaces and their profiles was carried out using fractal geometry, which allows us to display the topology of the object as close as possible to reality. For real heterogeneous rough structures, we have developed a through-counting method that takes into account the continuity of the total current at the interfaces of adjacent media, the effect of induced surface charge and surface current. This approach lets one avoid the necessity to set surface impedances depending on the structure of the field being determined and on the material properties.
SSRN Electronic Journal, 2022