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It is advisable to control characteristics and rate of formation of nanoscale fi lms on InP by introducing chemostimulators, modifi ers, or both simultaneously during the thermal oxidation of semiconductors. The chemostimulating effect of the compounds is determined by their transit role as oxygen transmitters or their catalytic function. Modifi ers can affect the composition, surface morphology, structure, and properties of the fi lm without changing the fi lm growth rate. The effect of chemostimulators and modifi ers on a single process of fi lm synthesis with the desired properties was assumed to be productive. Purpose: Establishment of the effect of certain complex chemostimulators and modifi ers on the kinetics, growth mechanism, and properties of complex oxide fi lms on InP in the nanoscale thickness range. The object of the study was indium phosphide FIE-1A orientation (100). SnO2/InP and (40 % Co3O4+60 % MnO2)/InP heterostructures with a layer thickness of ~ 30 nm were formed by magnetron sputtering. Sulphate was deposited through the aerosol phase, followed by air drying and annealing at 200 °C for 30 min for the formation of the Bi2(SO4)3/InP heterostructures. SnO2/InP and InP samples were thermally oxidized under the infl uence of AlPO4 and Bi2(SO4)3, respectively, introduced into the gas phase in the temperature range 490-570 °C in an oxygen stream for 60 min. The thickness of the fi lms was controlled by laser and spectral ellipsometry and their phase and elemental composition were established by XRD and Auger electron spectroscopy, respectively. For the determination of the electrophysical properties of the films, the contacts were sprayed with aluminium and the resistivity was determined. The fundamental role of the physicochemical nature of the chemostimulator, its ability to transit interactions and the renewability of oxide forms in the process of InP thermal oxidation was established. The introduction of phosphate groups from AlPO4 into thermal oxide fi lms, with or without the deposition of SnO2 on the surface, led to the fi lm resistance similar to that for the oxidation of SnO2/InP heterostructures without the additional introduction of phosphates and was 8.5·107 Ohm·cm. Bi2(SO4)3, being a modifi er of the composition and properties of the fi lms, did not have a signifi cant chemostimulating effect. Films grown under its infl uence had a semiconductor characteristics (r ~ 106 Ohm·cm). The most effective was a 40 % Co3O4+ 60 % MnO2 complex chemostimulator, which determined the accelerated (up to 70 %) formation of fi lm by the catalytic-transit mechanism (up to 70 %), being a part of the synthesized fi lms and capable of purposefully modifying their properties by varying the content of components in it (XRD, SE).

Chemostimulated thermal oxidation is one of the approaches to the formation of functional nanoscale fi lms on an AIIIBV surface. In order to obtain the desired result, it is necessary to reasonably choose an object that can act as a chemostimulator of the process or a modifi er of the structure and properties of films formed as a result of oxidation. The use of complex compounds capable of combining both of these functions seems to be effective. The purpose of the study was an investigation into the effect of nanoscale layers of the Mn3(P0.1V0.9O4)2 chemostimulator-modifi er on the process of thermal oxidation of GaAs, its composition, and morphology of the formed fi lms. The object of study was gallium arsenide (100) with nanosized layers of manganese vanadate-phosphate Mn3(P0.1V0.9O4)2 deposited on its surface. In order to increase the speed of the process and ensure the high chemical homogeneity of the product, it was proposed to use microwave activation of the synthesis of the chemostimulator-modifi er Mn3(P0.1V0.9O4)2 and its further deposition onto the surface of the semiconductor by the spin-coating method. The formed Mn3(P0.1V0.9O4)2/GaAs heterostructures were thermally oxidized in the temperature range 490–550 °C for 60 min in an oxygen stream. The thickness of the growing fi lms (by laser and spectral ellipsometry), their composition (X-ray phase analysis, Auger electron spectroscopy), and surface morphology (atomic force microscopy) were controlled. Studies of the kinetics of thermal oxidation of Mn3(P0.1V0.9O4)2/ GaAs heterostructures showed that the determining process is the solid-phase reaction, limited by diffusion in the solid phase, and the transit character of the chemostimulator without the catalytic effect occurs. It was revealed that manganese vanadate-phosphate promoted an increase in the growth of the formed fi lm by an average of 70–220% compared to the standard oxidation of GaAs, leads to the intensifi cation of secondary interactions of the oxides of the substrate components with the products of thermolysis of Mn3(P0.1V0.9O4)2 and the absence of segregation of arsenic in the fi lm in a non-oxidized state. Thermal oxidation of Mn3(P0.1V0.9O4)2/GaAs heterostructures results in the formation of nanoscale (50-200 nm) fi lms with a fairly pronounced relief. Further study of the electrophysical characteristics of the fi lms is necessary, since composition data suggest they possess a dielectric nature. This can be used in practice for the formation of fi lms on the surface of AIIIBV with functional purposes and with widely varying characteristics.

The purpose of this work was to reveal the infl uence of the phase composition and the crystallographic orientation of fi lm samples of Pd-Cu solid solution on the parameters of extraction and injection of atomic hydrogen in aqueous solution of sulphuric acid. The study was carried out using a two-step cathode-anode chronoamperometry method. The fi lms of the Pd53Cu alloy of various thickness were obtained by magnetron sputtering. They were characterised by the same phase (100% of theβ -phase of a solid solution) and chemical composition. It was confi rmed that during the initial period (≤ 4 s, the injection of atomic hydrogen proceeds in a mixed diffusion-phase-boundary regime, which later transforms into a purely diffusion mode. The kinetic and diffusion parameters of the stages of phase-boundary penetration of hydrogen and its subsequent solid-phase diffusion were calculated by the cathodic and anodic current decays. It was established that regardless of the thickness of the sample, an increase in the β phase fraction in the alloy leads to a marked increase in the diffusion coeffi cient of atomic hydrogen and, consequently, to an increase in the hydrogen permeability constant. The crystallographic orientation only affects the stage of phase-boundary penetration of hydrogen into the fi lm alloy. The data obtained confi rm the preferential movement of hydrogen along the grain body rather than over the interphase boundaries.