D. B. Zolotukhin

Generation of metal ions in the beam plasma produced by a forevacuum-pressure electron beam source

We report on the production of metal ions of magnesium and zinc in the beam plasma formed by a forevacuum-pressure electron source. Magnesium and zinc vapor were generated by electron beam evaporation from a crucible and subsequently ionized by electron impact from the e-beam itself. Both gaseous and metallic plasmas were separately produced and characterized using a modified RGA-100 quadrupole mass-spectrometer. The fractional composition of metal isotopes in the plasma corresponds to their fractional natural abundance.

Electron beam evaporation of boron at forevacuum pressures for plasma-assisted deposition of boron-containing coatings

We describe the use of a plasma-cathode electron source for electron beam evaporation of boron at forevacuum pressures (∼10 Pa) with subsequent deposition of boron-containing coatings on a titanium substrate. We analyze the process of electron beam heating and evaporation of boron, study the mass-to-charge composition of the gas and boron beam-produced plasma, apply such plasma for coating deposition, and investigate the elemental composition of the deposited film and its microhardness.

Modified quadrupole mass analyzer RGA-100 for beam plasma research in forevacuum pressure range

The industrial quadrupole RGA-100 residual gas analyzer was modified for the research of electron beam-generated plasma at forevacuum pressure range. The standard ionizer of the RGA-100 was replaced by three electrode extracting unit. We made the optimization of operation parameters in order to provide the maximum values of measured currents of any ion species. The modified analyzer was successfully tested with beam plasma of argon, nitrogen, oxygen, and hydrocarbons.

Deposition of dielectric films on silicon using a fore-vacuum plasma electron source

We describe an experiment on the use of a fore-vacuum-pressure, plasma-cathode, electron beam source with current up to 100 mA and beam energy up to 15 keV for deposition of Mg and Al oxide films on Si substrates in an oxygen atmosphere at a pressure of 10 Pa. The metals (Al and Mg) were evaporated and ionized using the electron beam with the formation of a gas-metal beam-plasma. The plasma was deposited on the surface of Si substrates. The elemental composition of the deposited films was analyzed.

Generation of uniform electron beam plasma in a dielectric flask at fore-vacuum pressures

We describe a system for the generation of spatially uniform and homogeneous dense plasma in a dielectric flask using a forevacuum-pressure plasma-cathode electron beam source. At optimum beam energy and gas pressure, the non-uniformity in plasma density distribution along the length of the flask is less than 10%, and the plasma density and electron temperature in the flask are greater than for the plasma produced in the vacuum chamber with no flask. The measured parameters of the beam plasma in the flask are compared to the predictions of a model based on balance equations.

Generation of a beam plasma by a forevacuum electron source in a space bounded by dielectric walls

A forevacuum plasma electron source is used to generate a beam plasma and measure its parameters in a cylindrical thin-walled quartz bulb. Differences in the gas pressure dependences of the plasma concentration and potential are found when the plasma-generating beam is injected into the dielectric bulb and propagates in an unbounded space.

Inverse time-of-flight spectrometer for beam plasma research

The paper describes the design and principle of operation of an inverse time-of-flight spectrometer for research in the plasma produced by an electron beam in the forevacuum pressure range (5-20 Pa). In the spectrometer, the deflecting plates as well as the drift tube and the primary ion beam measuring system are at high potential with respect to ground. This provides the possibility to measure the mass-charge constitution of the plasma created by a continuous electron beam with a current of up to 300 mA and electron energy of up to 20 keV at forevacuum pressures in the chamber placed at ground potential. Research results on the mass-charge state of the beam plasma are presented and analyzed.

On the role of secondary electrons in beam plasma generation inside a dielectric flask by fore-vacuum plasma-cathode electron source

The paper presents the results of experimental research and numerical simulation, demonstrating a considerable influence of secondary electrons on parameters of the beam-produced plasma generated at a pressure range of 1–13 Pa by injection of a continuous (with current of tens mA) electron beam into a dielectric (quartz) flask. An electron beam was formed by a fore-vacuum plasma-cathode electron source based on a hollow cathode discharge. The secondary electrons were emitted as a result of high-energy (3–8 keV) electron beam bombardment mainly a bottom end of the flask. These electrons provide an additional contribution to the ionization of the gas and also affect on the longitudinal distribution of the plasma density along the flask.

Synthesis of the boron-based coating in beam plasma using fore-vacuum electron source

Article presents the experimental results on deposition of boron-containing coating on titanium substrate by the novel method of reactive electron-beam evaporation of nonmetallic target at fore-vacuum pressures. The synthesis of the coating was made from the plasma produced by electron beam in fore-vacuum (1-10 Pa) pressure range, during evaporation of boron target followed by ionization of boron particles by the same electron beam. Analysis of the deposited coating show that the microhardness of the titanium sample increases significantly (up to 8 times) after deposition of the boron-containing coating. Results of the surface profile analysis demonstrate the decrease in surface roughness as a result of the deposition of the boron-containing film. These results, together with a high deposition rate (about 1 micron per minute), show the high efficiency of the reactive electron beam method of coating deposition during the evaporation of nonmetallic targets at the fore-vacuum pressures.

Electron beam deposition of ceramic coatings at fore-vacuum pressure

We have described a method for the deposition of ceramic coatings in which the electron beam formed by a plasma-cathode e-beam source operating at fore-vacuum pressure is used for evaporation of ceramic target material. Homogeneous nonporous alumina coatings were formed as a result of e-beam evaporation of an insulating alumina target; the coating thickness can be controlled by varying the process time and/or the beam power. Important advantages of such approach are that because of the inherent charge neutralization of the non-conducting e-beam target via low energy positive ions formed in the beam plasma, there is essentially no limit to the delivered electron beam power, and, because of the use of a plasma-cathode electron beam source, the system is compatible with quite modest vacuum such as provided by mechanical pumping only.