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The spectrophotometric method is widely used for the qualitative and quantitative analysis of substances, in the study of the structure and composition of various compounds. The article solved the actual problem of spectrophotometers measuring process automating. The structure of the spectrophotometer control unit based on the Arduino Uno hardware platform has been proposed, a stepper motor driver scheme, providing replacement of the manual rotation system of the spectrophotometer diffraction grating to a system using modern stepper motors has been developed. It made it possible to increase the measurement efficiency by reducing the measurement time and improving the metrological characteristics of the spectrophotometer (the limiting absolute error in setting the wavelength is reduced from ± 0.5 nm to ± 0.3 nm).

The article is devoted to the actual problem of the synthesis of polycrystalline diamonds with a combination of unique electrophysical parameters (high hardness and thermal conductivity, low dielectric constant, high radiation resistance, etc.), due to which diamonds are promising materials for micromechanical devices.The features of synthesizing dense thick films of polycrystalline diamond with the required parameters are considered.The work justifies the choice of the mask, establishes the modes of experimental formation of a topological pattern using the method of plasma-chemical etching. The results of an experimental study of the obtained pattern confirm its high accuracy (the error does not exceed ± 1.2 μm relative to the elements on the photomask) and the minimum structure etching under the protective mask is ≈1.5 μm.As a result of the research, the possibility of manufacturing a high-precision pressure sensor based on polycrystalline diamond has been revealed; the technological modes of micro-processing of a polycrystalline diamond film by plasma-chemical etching, affecting the reproducibility of the required material properties, are determined.

One of the promising types of solar cells are solar cells of a new generation based on hybrid organic-inorganic perovskites (HOIP). Improving the quality parameters of solar cells is one of the urgent tasks of alternative energy, the solution of which is connected with the analysis of the causes affecting the quality parameters of the functional layers. To solve it, control methods and quality management, such as Pareto and Ishikawa diagrams, have been applied. Using these methods, transparent conductive coatings and metal oxide layers of solar cells based on HOIP were investigated. This made it possible to identify the following main problems in obtaining functional layers of solar cells based on hybrid organo-inorganic perovskites: defects in the morphology of the films surface, deviations from a given thickness, installations faults. These three categories account for 80% of all faults associated with the production of functional solar cells layers based on HOIP. It has been established that the main causes of defects include the wrong choice of technological regimes and obtaining methods, as well as improper handling of equipment and materials

The requirements to methods for measuring the oxide coatings thickness are formulated, allowing measurements to be carried out directly in the process of their formation in real time, which is a necessary condition for the controlled synthesis of coatings with desired properties. Based on a systematic approach, the existing methods for measuring the oxide coatings thickness and their metrological characteristics are analyzed. As a result, it was found that the most suitable for measuring the oxide coatings thickness during micro-arc oxidation are electrical methods, which include the method proposed by the authors based on a frequency integrating scanning transducer. The method proposed by authors allows to measure the thickness of the oxide layers directly in the process of their formation with high accuracy. This method is implemented in an intelligent automated system for the controlled synthesis of oxide coatings.

The study results of the dependences of the refractive index and samples transmittance of transparent conductive films of tin dioxide depending on wavelength are presented. Films with different doping levels, with different solutions volumes were synthesized on an automated installation by spray pyrolysis. It is shown that the transmittance practically does not depend on the amount of substance sprayed onto the substrate; the transmittance practically does not depend on the solution volume, but depends on the impurity concentration. The chemical composition and temperature of film deposition influence on its refractive index is established. The research results can be used in the development of technologies for the manufacture of optoelectronic structures containing transparent conductive coatings.

The results of the study of the technological regimes of the formation of a microcantilever beam of layered heterostructures based on the integration of smart material and silicon carbide are presented. Layers of silicon dioxide (SiO2), silicon nitride, silicon carbide, and platinum (lower electrode) are successfully formed on a silicon substrate. The results of an experimental study of the Pt / PZT / Pt / SiC heterostructures parameters confirmed the technological compatibility of the layers and the promise of using these structures in sensors of dynamic deformation when creating new generation sensors, including those operating in heavy rocket conditions of space technology.

The hardware structure of an automated system for bioimpedance measuring is represented. The schematic solution of the probe current source, which depends on the methodological and instrumental errors of measurement results is proposed. The minimization of the methodical error of impedance measurement is achieved due to the influence of the parasitic capacitance of the investigated object. An automated system allows you to measure the bioimpedance in the frequency range from 300 Hz to 2 MHz with basic relative error not exceeding ±0.1 %. Reduction of random error is achieved by multiple measurements with subsequent processing of the measurement results; subjective errors are eliminated by the measurements automating.

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.

Transparent conductive coatings based on thin films of metal oxides are widely used in various optoelectronic devices and appliances. The article is devoted to identifying the most effective way to study electro-physical properties of coating of antimony doped tin dioxide (ATO coatings). Tin dioxide thin films are obtained by spray-pyrolysis technique on glass substrates. To determine the electrophysical parameters the two most common methods were used: four-probe method (probes are linearly) and the method of Van der Pauw.