Publications by authors named "Yushkov G"

In an ion source based on a pulsed planar magnetron sputtering discharge with gas (argon) feed, the fraction of metal ions in the ion beam decreases with decreasing gas pressure, down to the minimum possible working pressure of the magnetron sputtering discharge. The use of a supplementary vacuum arc plasma injector provides stable operation of the pulsed magnetron sputtering discharge at extremely low pressure and without gas feed. Under these conditions, the pressure dependence of the gaseous ion fraction displays a maximum (is nonmonotonic).

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Supersonic plasma flows with densities of 10-10 cm find application in various fields of physics and technology such as surface modification, simulation of plasma impact in fusion facilities, and laboratory studies of space phenomena. The work outlined here describes a pulsed vacuum arc source of supersonic dense metal plasma flow. The design, working principle, features of the power supply circuit, and main parameters of the plasma source in relation to the parameter of the vacuum arc pulse are discussed.

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The magnetron discharge plasma is commonly used in thin film deposition processes, but it can also be utilized for ion beam production. We have developed and investigated an ion source based on planar magnetron discharge. We show that under certain conditions, the discharge, running in a high current pulsed mode, effectively produces plasmas with a high fraction of ions formed from the magnetron target material.

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Unlabelled: The topicality of the problem stated in the title of the this article is attributable to the lack of up-to-date information on the treatment of thermal skin wounds with the use of short wavelength ultraviolet radiation (UVR). The objective of the present study was to evaluate the effectiveness of the courses of short wavelength ultraviolet radiation under experimental conditions using a model of standardized thermal skin wounds in rabbits starting from the proliferative phase of the healing.

Material And Methods: The experiments were carried out on 24 grey rabbits.

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Smaller semiconductors require shallow, low energy ion implantation, resulting space charge effects, which reduced beam currents and production rates. To increase production rates, molecular ions are used. Boron and phosphorous (or arsenic) implantation is needed for P-type and N-type semiconductors, respectively.

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High ion charge state is often important in ion beam physics, among other reasons for the very practical purpose that it leads to proportionately higher ion beam energy for fixed accelerating voltage. The ion charge state of metal ion beams can be increased by replacing a vacuum arc ion source by a vacuum spark ion source. Since the voltage between anode and cathode remains high in a spark discharge compared to the vacuum arc, higher metal ion charge states are generated which can then be extracted as an ion beam.

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The paper reports on a study of the mass-charge state of the plasma produced in a vacuum arc discharge with composite cathodes which were copper-disk coated with a hydrogenated Zr film of thicknesses 9, 22, and 35 μm. The cathodes allow the generation of multicomponent gas and metal ion beams with a hydrogen ion content from several to several tens of percent. Also investigated is the dependence of the H ion fraction in a beam on the Zr film thickness during erosion to the point of disappearance of Zr peaks in mass-charge spectra.

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Boron ion beams are widely used for semiconductor ion implantation and for surface modification for improving the operating parameters and increasing the lifetime of machine parts and tools. For the latter application, the purity requirements of boron ion beams are not as stringent as for semiconductor technology, and a composite cathode of lanthanum hexaboride may be suitable for the production of boron ions. We have explored the use of two different approaches to boron plasma production: vacuum arc and planar high power impulse magnetron in self-sputtering mode.

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The data on inhibition of the growth of microorganisms of a characteristic spectrum and antibiotic resistance isolated from long-term healing wounds by light of various wave ranges are presented. The growing cultures on blood agar were exposed to polarized light, red and infrared, ultraviolet of medium- and short-wave continuous modes accustomed in physiotherapy of wounds.The effect of light in some way induced inhibition of the growth, but complete recovery was stated only after the use of ultraviolet light when confirmed quantitatively in terms of the CFU.

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A boron ion source based on planar magnetron discharge with solid boron target has been developed. To obtain a sufficient conductivity of the boron target for high current discharge ignition, the target was heated to the temperature more than 350 °C. To reach this temperature, thermally isolated target was heated by low-current high-voltage magnetron DC discharge.

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The hybrid high charge metal ion source based on vacuum arc plasma heated by gyrotron radiation into simple magnetic trap has been developed. Two types of magnetic traps were used: a mirror configuration and a cusp one with inherent "minimum-B" structure. Pulsed high power (>100 kW) gyrotrons with frequency 37.

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The Metal Vapor Vacuum Arc (MEVVA) ion sources are capable of generating ion beams of almost all metals of the periodic table. For this kind of ion source, a combination of gas feeding with magnetic field allows the simultaneous generation of both metal and gaseous ions. That makes the MEVVA ion source an excellent instrument for science and application.

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The paper describes the principle of operation, design special features, and parameters of an inverted time-of-flight spectrometer. The spectrometer is designed in such way that its deflecting plates, drift tube, and primary measuring system are at high potential with respect to the ground potential, whereas plasma is formed near grounded electrodes. This type of configuration greatly extends the application range of the device, making it possible to measure the mass-to-charge composition of plasma with wide range of parameters.

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In this work, the possibility to increase the surface conductivity of ceramic insulators through their treatment with accelerated metal ion beams produced by a MevvaV.Ru vacuum arc source is demonstrated. The increase in surface conductivity is made possible due to experimental conditions in which an insulated collector is charged by beam ions to a potential many times lower than the accelerating voltage, and hence, than the average beam ion energy.

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An ion source based on a two-stage discharge with electron injection from a cold emitter is presented. The first stage is the emitter itself, and the second stage provides acceleration of injected electrons for gas ionization and formation of ion flow (<20 eV, 5 A dc). The ion accelerating system is gridless; acceleration is accomplished by an electric field in the discharge plasma within an axially symmetric, diverging, magnetic field.

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This paper presents measurements of the angular distribution of the plasma components and different charge states of metal ions generated by a MEVVA-type ion source and measured by a time-of-flight mass-spectrometer. The experiments were performed for different cathode materials (Al, Cu, and Ti) and for different parameters of the vacuum arc discharge. The results are compared with prior results reported by other authors.

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Vacuum arc ion sources have been made and used by a large number of research groups around the world over the past twenty years. The first generation of vacuum arc ion sources (dubbed "Mevva," for metal vapor vacuum arc) was developed at Lawrence Berkeley National Laboratory in the 1980s. This paper considers the design, performance parameters, and some applications of a new modified version of this kind of source which we have called Mevva-V.

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We suggest a Penning-type discharge as a trigger discharge for fast development of pulsed electron cyclotron resonance plasma. The Penning-type discharge glows at a low pressure as needed. Gyrotron radiation (75 GHz, 200 kW, 1 ms) was used for plasma heating.

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A method for generating high charge state heavy metal ion beams based on high power microwave heating of vacuum arc plasma confined in a magnetic trap under electron cyclotron resonance conditions has been developed. A feature of the work described here is the use of a cusp magnetic field with inherent "minimum-B" structure as the confinement geometry, as opposed to a simple mirror device as we have reported on previously. The cusp configuration has been successfully used for microwave heating of gas discharge plasma and extraction from the plasma of highly charged, high current, gaseous ion beams.

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We have made and tested a very low energy gaseous ion source in which the plasma is established by a gaseous discharge with electron injection in an axially diverging magnetic field. A constricted arc with hidden cathode spot is used as the electron emitter (first stage of the discharge). The electron flux so formed is filtered by a judiciously shaped electrode to remove macroparticles (cathode debris from the cathode spot) from the cathode material as well as atoms and ions.

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We have designed, made, and demonstrated a broad-beam, dc, ion source based on a two-stage, hollow-cathode, and glow discharges plasma. The first-stage discharge (auxiliary discharge) produces electrons that are injected into the cathode cavity of a second-stage discharge (main discharge). The electron injection causes a decrease in the required operating pressure of the main discharge down to 0.

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An ion source based on a planar magnetron sputtering device with thermally isolated target has been designed and demonstrated. For a boron sputtering target, high target temperature is required because boron has low electrical conductivity at room temperature, increasing with temperature. The target is well-insulated thermally and can be heated by an initial low-current, high-voltage discharge mode.

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This paper presents the results of time-of-flight mass spectrometry studies of the elemental and mass-to-charge state compositions of metal ion beams produced by a vacuum arc ion source with compound cathode (WC-Co(0.5), Cu-Cr(0.25), Ti-Cu(0.

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Electron cyclotron resonance ion sources (ECRISs) are particularly useful for nuclear, atomic, and high energy physics, as unique high current generators of multicharged ion beams. Plasmas of gas discharges in an open magnetic trap heated by pulsed (100 micros and longer) high power (100 kW and higher) high-frequency (greater than 37.5 GHz) microwaves of gyrotrons is promising in the field of research in the development of electron cyclotron resonance sources for high charge state ion beams.

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