Depth distribution of the mean losses of electron-beam energy in a sample: Application in problems of quantitative X-ray spectral microanalysis

A formula describing the depth dependence of the distribution of the mean energy of a electron beam in a solid target is obtained within the framework of the discrete model of the multiple scattering of charged particles in substances. It is verified whether this formula corresponds to experimental results, and the possibility of using it to solve practical problems of X-ray spectral microanalysis is shown.     

Statistical analysis of a model of collective motion of minority charge carriers using the projection method

For a model of the collective motion of minority charge carriers (MCCs) generated by various external energy sources (broad electron and light beams) in a homogeneous semiconductor material, a method for approximating their statistical characteristics (mathematical expectation and autocorrelation function) is described. The developed approach uses the projection method based on application of the theory of matrix operators. It was assumed that a material’s electrophysical parameters (MCC lifetime, diffusivity, and surface recombination rate) are random quantities and obey the truncated normal distribution law. A comparative analysis of the dispersion effect of these quantities on the MCC depth distribution is performed.     

Modifying the properties of ferrite materials with a hexagonal structure via treatment in corona discharge plasma

The influence of treatment in corona discharge plasma on the magnetic properties of BaFe₁₂O₁₉ single- and polycrystalline ferrites, as well as structural-chemical transformations in their crystal lattices, are studied. The revealed dependence between structural-sensitive microscopic parameters and the duration of corona-discharge-plasma treatment indicates the manifestation of the corona-electret effect in BaFe₁₂O₁₉ single crystals.     

On applicability of confluence analysis in cathodoluminescence microscopy for interval estimation of diffusion lengths of minority carriers and depths of subsurface regions with depletion of majority carriers

Mathematical modeling is applied to examine the possibilities for obtaining point and interval simultaneous estimates for two parameters of a semiconducting material, these being the diffusion length of minority carriers and the depth of subsurface regions with depletion of majority carriers. For the first time in cathodoluminescence microscopy, the method of confluence analysis has been employed to tackle the twodimensional inverse problem in question. Our calculations involved the parameters characteristic of real direct band-gap semiconducting materials.     

On one possibility of the mathematical modeling of the dependence of cathodoluminescence intensity on the energy of beam electrons with the use of the power series approximation in the problem of identifying the parameters of semiconductor materials

The possibility of calculating the dependence of the cathodoluminescent radiation intensity on the energy of the beam electrons is described using a model of independent sources and a power series approximation. The obtained expression can be used to solve some inverse problems of identifying the electrophysical parameters of semiconductor materials. The mathematical modeling is carried out in the energy range typical of electron-probe devices and for material parameters typical of actual direct-gap semiconductors.     

On Selection of the initial approximation in the method of confluence analysis for cathodoluminescence identification of the parameters of direct-gap semiconductors for the quadratic recombination of minority charge carriers

The problem of selection of the initial approximation for the task of identifying the electrical parameters of direct-gap semiconductors by the method of confluence analysis using the dependence of the intensity of the monochromatic cathodoluminescence caused by the quadratic recombination of minority charge carriers on the electron-beam energy is considered.     

On a modified projection scheme of the least-squares method for the modeling of the distribution of minority charge carriers generated by an electron beam in a homogeneous semiconductor material

A modified projection scheme of the least-squares method is considered for modeling of the distribution of minority charge carriers generated by an electron beam in a homogeneous semiconductor material. The order estimate is given, and the condition for the computational stability of the proposed modified projection scheme is obtained in the form of the limiting relation.     

Characterization of pore size distribution in porous silicon by NMR cryoporosimetry and adsorption methods

The results of studying the pore size distribution of mesoporous silicon by NMR cryoporosimetry are described. These data are compared with the results obtained by adsorption methods.     

Analysis of a model of minority charge-carrier distributions generated in a three-layer semiconductor structure by a wide electron beam

Based on the use of a model of independent sources, a method is described for the calculation of minority-charge-carrier distributions generated in three-layer planar semiconductor structures by a wide electron beam with energy typical of electron probe devices (5–30 keV). It is shown that, in limiting cases, equations describing these distributions agree with the data obtained previously for a two-layer semiconductor structure.     

Energy loss spectra for a fast charged particle beam transmitted through a material film of specified thickness

The effect of the spatial distribution of a material atomic electrons on the beam energy dissipation for monoenergetic charged particles (electrons and protons) during their transport through a film target has been investigated.