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When controlling the quality parameters of transparent conductive coatings, the problem of analyzing the causes leading to defects arises. The use of the following seven basic tools for quality control of methods with a 95% probability allows the problem to be solved. For the initial assessment of the samples quality, it was decided to use the following quality control methods: Ishikawa diagram, Pareto diagram, control cards. An analysis of the proposed Ishikawa diagram revealed that the significant factors affecting the quality of transparent conductive oxides are the choice of precursor and impurities for the solution, the preparation of the solution and substrate, the choice of production method, the design of the atomizer and reaction chamber. According to the Pareto diagram, the most common defect is high resistance, the reason for the increase of which must be corrected first. $\text{ABC}$ analysis showed that the most significant group A includes the following defects: unsatisfactory high resistance, unsatisfactory uniformity, and unsatisfactory high thickness. The control card for the “resistance” parameter shows that a number of surface resistance values are out of range. But considering that the surface resistance values that are under the lower boundary curve are small, which, on the contrary, affects the quality of the coating for the better; it is worth taking into account only the upper boundary line.

A model that allows obtaining a systematic analytical description of the micro-arc oxidation (MAO) process parameters influence on the microdischarges characteristics using the Ishikawa cause-effect diagram, graph theory, and set theory is proposed. Expressions for the model parameters characterizing the electrolyte conductivity and the microdischarges power are obtained. The proposed model is universal and can be used to study any multifactorial processes or complex objects.

At present, the micro-arc oxidation technology, which makes it possible to obtain oxide coatings with unique properties on the surface of metals and alloys of the valve group, is increasingly used in science and technology. These coatings are used not only to solve traditional problems, such as protecting machine parts and devices from wear and corrosion, but also when developing new-generation prostheses with antibacterial properties, as well as in dosimetry. The disadvantage of this technology is the lack of controllability caused by a large number of heterogeneous factors that jointly affect the coating properties. To solve this problem, on the basis of graph theory and set theory, a model was developed that describes the totality of the influencing factors of the micro-arc oxidation process and the relationship between them, aimed at finding the most informative factors to be experimentally determined in the coating formation process. The analysis of the developed model showed that the most important technological parameters affecting the properties of the formed oxide layers are forming voltage, time and current density. It is shown that many characteristics of the resulting coatings (micro-hardness, thickness, porosity, wear resistance and thermal conductivity) can be calculated by measuring the time dependences of the voltage (forming curves) and the current of the micro-plasma process or dynamic current-voltage characteristics. The proposed model has a limitation associated with the need to fix a number of technological parameters (temperature, concentration of electrolyte components in the electrolyte, current pulse frequency) when measuring the above dependencies. The model can be used both in scientific research and in production when selecting the optimal technological parameters of the micro-arc oxidation process.

Silicon is one of the widely used materials in the manufacture of modern electronic components and functional electronics devices. The manufacturing quality of silicon plates determines the quality parameters of products. The purpose of the researched studies is to establish the causes of silicon rasters during anisotropic etching and the geometry violation of the formed structures to improve the quality parameters of the technological process of micromechanical sensors manufacturing. Based on the use of selective etching methods, the article presents the results of the quality parameters estimation of silicon wafers used in the micromechanical sensors manufacture. The detecting methods of swirl defects and dislocations are described. The method for determining swirl defects is based on the difference in the etching rate of a silicon wafer areas containing micro-defects compared to crystallographically perfect areas. The method of dislocations identifying is based on the fact that at the intersection of dislocations and the wafers surface, the rate of silicon etching is higher, as a result of which dislocations are revealed as etch pits. Photographs of the wafers surface with the identified defects types are presented. The use of methods for selective silicon etching allowed us to experimentally reveal two types of silicon wafer defects: swirl defects (micro-defects) and dislocations, which have different causes, described in the article. The presented techniques can be practically used at the input quality control of silicon wafers.

An analytical description of the process parameters and various industry sorts of external factors influence (heat, electrical, magnetic, mechanical) on active dielectrics properties (relative permittivity, polarization) that govern the materials use in functional electronics elements is presented. The article proves expediency of x-rays use to improve the reproducibility of dielectric properties of hydrogen-containing ferroelectrics (for example, triglycine sulfate). Higher reproducibility of parameters is due to the presence of flat areas in dependence of the relative permittivity on the electric field e(E) during γ-radiation exposure, and therefore the additional errors of dialectic properties measurement are reduced significantly due to the impossibility of fixing the exact values of process parameters. For example, when the radiation dose D = 50 kR extra measurement error e is reduced not less than 2.5 times.

The article presents modeling of the dielectric permeability and the angle tangent of dielectric loss of two-layer ferroelectric structure of BSTO type on temperature and the layers thickness. The described modeling way can be used in the calculation or the indirect measurement of dielectric parameters of heterogeneous structures composed of ferroelectric thin films. The formulas for estimating the errors of the modeling results of the dielectric permeability and the angle tangent of dielectric loss are made.