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We present a study of structural features of diamond coatings prepared by chemical vapor deposition from a hydrogen/methane mixture activated by a microwave discharge using a high-speed jet to transport the mixture to molybdenum substrates heated up to 525 °C, 690 °C, and 1000 °C. The influence of the substrate temperature on morphology, composition, and structure of diamond coatings are studied by scanning electron microscopy, Raman spectroscopy, X-ray photoelectron spectroscopy, and near edge X-ray absorption fine structure. The diamond crystals enlarge in size, their density on the substrate increases, while the quality and the crystal surface purity are enhanced as a result of temperature increase.

The gas-jet method of the deposition of diamond-like structures using super-high-frequency (SHF) discharge for activating gases is considered. Direct statistical simulation is applied to analyze the gasdynamic processes occurring in the conditions of the gas-jet deposition of diamond structures. An activated gas flow in a nozzle is investigated and a considerable influence of the processes in the compressed layer formed near the substrate on the rate of synthesis of diamond structures is established. The regimes of flow of mixture components activated in the discharge chamber toward the substrate are determined and a considerable deceleration of heavy components in the compressed layer is found to exist. It is shown that with increase in the pressure in the deposition chamber from 10 to 80 Torr the crystal growth rate increases fourfold at the expense of an increase in the specific flux of the activated components toward the substrate.

A method of gas-phase deposition of diamond structures with the use of high-velocity jets for transporting gases activated in a microwave plasma to the substrate is developed. The diamond structures are synthesized from a hydrogen–methane mixture with the methane concentration of 1%. The influence of the gas mixture flow rate on the synthesis of the diamond structures with an unchanged composition of the mixture, pressure in the deposition chamber, and substrate temperature is studied. It is found that an increase in the flow rate leads to an increase in the polycrystalline film density and in the size of the diamond crystals forming the film. The composition of the mixture at the discharge chamber exit is numerically analyzed for different flow rates of the gas mixture. A correlation of the mixture composition with the growth rate and quality of the diamond structures is demonstrated.

The formation of a fluoropolymer coating by chemical deposition has been studied experimentally. It has been found that increasing the flow rate of the precursor gas leads to a decrease in the growth rate of the coating. Deposition conditions were analyzed, and the gas-dynamic parameters of the process were estimated. The estimates are consistent with experimental data.

Thin films of amorphous silicon with inclusions of a nanocrystalline silicon phase have been obtained by the method of gas-phase chemical deposition with hot-wire activation of the precursor. The influence of the gas pressure and of the hydrogen–monosilane ratio on the rate of growth and the degree of crystallinity of the deposited silicon has been investigated. Characteristic values of the synthesis parameters for obtaining silicon films of various degrees of crystallinity have been established.

In this work, we studied influence of fluoropolymer thin film deposition on wettability of the silicon oxide nanowires array. Deposition of fluoropolymer coating on the silicon oxide nanowires array changes the surface properties from hydrophilic to hydrophobic, and micro and nano scale surface roughness does not change significantly. In addition, it was shown that the deposition of fluoropolymer coating on nanowires protects the nanostructures from bundling together as a result of the attractive capillary forces that arise during evaporative drying.

The gas-jet deposition of carbon and diamond-like films on a substrate with precursor gas activation by a hot wire mesh has been studied experimentally. Several designs of the wire activator for depositing films from a gaseous mixture of CH4, H2, and Ar have been tested. The carbon structure of obtained films was determined by Raman spectroscopy.

In this paper the results of a study of the deposition of silver nanoparticles with characteristic particle sizes from several nanometers to tens of nanometers obtained by gas-jet deposition from a specially developed thermal source are presented. The characteristics of the thermal source are given as dependences of nanoparticle size values on the source temperature and pressure. Flow regions responsible for the formation of metal clusters have been detected.

A new method of gas-jet deposition of metal-polymer composites with simultaneous deposition of polymer matrices and silver clusters from two gas-dynamic sources is presented. Specific features of cluster deposition and the properties of composite films are described. Results on the antibacterial effect of silver-polymer composites on stock cultures of various bacteria are reported.

The goal of this work is the elaboration of the new method of Hot Wire Chemical Vapor Deposition, when the activation of a precursor gas performs in a high speed jet, in which a hot-wire net is inserted. Oriented in a jet, transportation of a gas precursor adds new parameters to control a process of deposition. The first experiments were performed with the supersonic jet of C 2 F 4 , issued from the sonic nozzle after pyrolysis of the bulk Teflon in the high temperature reactor. The most interesting results are obtained by changing the net temperature. The film morphology is radically changed from separate fragments with micron characteristic sizes up to nanodisperse fractal-porous accretions.

The results of study of the low density gas jet deposition for different schemes are presented. The possibility to activate the precursor gas flow by a hot wire net allows to obtain different structures of deposited films. The experimental results are accompanied by data for flow structure, density, velocity, and temperature determined by the DSMC method, which are useful for the understanding of deposition process. The deposition of metal‐polymer film by interaction of two separate jets is realized.

The fluoropolymer coatings of different morphologies are deposited by the HWCVD (Hot Wire CVD) method. The effect of activator filament temperature on the structure of fluoropolymer coating is shown. The results of studying the hydrophobic fluoropolymer coatings with different structures, deposited by the HWCVD method, are presented.