High intensity proton source based on a hollow-cathode reflex discharge.

We describe here the electrode system, design, and parameters of an ion source based on a Penning-type hollow-cathode reflex discharge developed for generation of proton beams. Especially for proton beam generation, a modified geometry of both hollow and reflex cathodes was fabricated. The working gas is molecular hydrogen.

Forevacuum plasma-cathode electron source for generation of a ribbon beam over a wide pressure range.

We describe the results of our investigations of the generation of a ribbon electron beam (10 × 220 mm2) by a two-stage discharge system based on a hollow-cathode glow discharge plasma. The source design enables operation in the pressure range 2 × 10-2 to 10 Pa. At a beam accelerating voltage of 8 kV, the beam current is 450 mA at a pressure of 2 × 10-2 Pa and 150 mA at a pressure of 10 Pa.

Validation of Amazon Halo Movement: a smartphone camera-based assessment of movement health.

Movement health is understanding our body's ability to perform movements during activities of daily living such as lifting, reaching, and bending. The benefits of improved movement health have long been recognized and are wide-ranging from improving athletic performance to helping ease of performing simple tasks, but only recently has this concept been put into practice by clinicians and quantitatively studied by researchers. With digital health and movement monitoring becoming more ubiquitous in society, smartphone applications represent a promising avenue for quantifying, monitoring, and improving the movement health of an individual.

Ion beam composition in ion source based on magnetron sputtering discharge at extremely low working pressure.

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).

Broad-beam plasma-cathode electron beam source based on a cathodic arc for beam generation over a wide pulse-width range.

We describe the design, parameters, and characteristics of a modified wide-aperture, plasma-cathode electron beam source operating in the pressure range of 3 Pa-30 Pa and generating large-radius, low-energy (up to 10 keV) electron beams with a pulse width varying from 0.05 ms to 20 ms and a beam current up to several tens of amperes. A pulsed cathodic arc is used to generate the emission plasma, and a DC accelerating voltage is used to form the electron beam.

Plasma electron source for generating a ribbon beam in the forevacuum pressure range.

We describe a plasma-cathode electron beam source based on a hollow cathode glow discharge and operating in the forevacuum pressure range that produces a steady-state ribbon beam. The electron beam is generated in the pressure range of 10-30 Pa. A multi-aperture electron extraction and beam formation system is used to provide beam stability and enhanced uniformity of beam current density, allowing the use of this kind of device for beam-plasma surface modification over relatively large areas.

Forevacuum-pressure plasma-cathode high-power continuous electron beam source.

We describe a plasma-cathode electron beam source based on a hollow-cathode discharge that is capable of generating a 9 kW dc electron beam at an accelerating voltage of 20 kV, with helium as a working gas at a pressure of 30 Pa. A test run of ∼50 operational hours did not indicate any significant degradation of the electron source extraction system or other structural components, and we estimate the operational lifetime of the source at about 100-120 h.

Pulsed vacuum arc plasma source of supersonic metal ion flow.

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.

Ion source based on a circular anode layer plasma thruster.

A new version of pulsed ion source based on plasma thruster technology has been developed and tested. The ion source design uses a circular anode layer geometry in which the ion beam is extracted radially from the full circumference. The source has been tested for operation in argon, nitrogen, and air at a gas flow rate of up to 20 SCCM with discharge current and voltage measurements in low- and high-current modes.

Effects of gas pressure and discharge current on beam composition in a magnetron discharge ion source.

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.

Boron vacuum-arc ion source with LaB cathode.

We describe a pulsed vacuum arc ion source with a lanthanum hexaboride (LaB) cathode for high-dose selective implantation of B and B isotope ions. The design and main parameters of the source and its plasma generator are described, and research data are reported on the formation, transport, and magnetic separation of B and B ions extracted from the erosion plasma of a vacuum arc discharge. Cathode spots are initiated by flashover across an alumina ceramic block of diameter ∼2.

Double-coil magnetic focusing of the electron beam generated by a plasma-cathode electron source.

We present the results of our investigations of magnetic focusing of the electron beam generated by a plasma-cathode electron source in the forevacuum pressure range (10-30 Pa). We show that a magnetic double-focusing system employing two separate field coils with the main magnetic coil located close to the beam collector at the focal plane provides effective and efficient focusing of the electron beam. With our e-beam source, this focusing system produces a power density of more than 1 MW/cm at the electron beam focus with an accelerating voltage of 30 kV and a beam current up to 60 mA.

Using X-ray spectroscopy of relativistic laser plasma interaction to reveal parametric decay instabilities: a modeling tool for astrophysics.

By analyzing profiles of experimental x-ray spectral lines of Si XIV and Al XIII, we found that both Langmuir and ion acoustic waves developed in plasmas produced via irradiation of thin Si foils by relativistic laser pulses (intensities ~10 W/cm). We prove that these waves are due to the parametric decay instability (PDI). This is the first time that the PDI-induced ion acoustic turbulence was discovered by the x-ray spectroscopy in laser-produced plasmas.

Sputtering of pure boron using a magnetron without a radio-frequency supply.

Boron at room temperature is insulating and therefore conventionally sputtered using radio-frequency power supplies including their power-matching networks. In this contribution, we show that through a suitable ignition assistance, via temporary application of a high voltage (∼600 V) to the substrate holder or auxiliary electrode, the magnetron discharge can be ignited using a conventional mid-frequency power supply without matching network. Once the discharge is ignited, the assisting voltage can be reduced to less than 50 V, and after the boron target surface is at elevated temperature, thereby exhibiting sufficient conductivity, the assisting voltage can be turned off.

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.

Surface modification of ferritic steels using MEVVA and duoplasmatron ion sources.

Metal Vapor Vacuum Arc (MEVVA) ion source (IS) is a unique tool for production of high intensity metal ion beam that can be used for material surface modification. From the other hand, the duoplasmatron ion source provides the high intensity gas ion beams. The MEVVA and duoplasmatron IS developed in Institute for Theoretical and Experimental Physics were used for the reactor steel surface modification experiments.

Operating modes of a hydrogen ion source based on a hollow-cathode pulsed Penning discharge.

An ion source based on a hollow-cathode Penning discharge was switched to a high-current pulsed mode (tens of amperes and tens of microseconds) to produce an intense hydrogen ion beam. With molecular hydrogen (H2), the ion beam contained three species: H(+), H2(+), and H3(+). For all experimental conditions, the fraction of H2 (+) ions in the beam was about 10 ÷ 15% of the total ion beam current and varied little with ion source parameters.

Molecular ion sources for low energy semiconductor ion implantation (invited).

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.

A vacuum spark ion source: High charge state metal ion beams.

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.

Lifetime of hydrogenated composite cathodes in a vacuum arc ion source.

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.

Boron ion beam generation utilizing lanthanum hexaboride cathodes: Comparison of vacuum arc and planar magnetron glow.

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.

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.

Atomic Layer Deposition from Dissolved Precursors.

We establish a novel thin film deposition technique by transferring the principles of atomic layer deposition (ALD) known with gaseous precursors toward precursors dissolved in a liquid. An established ALD reaction behaves similarly when performed from solutions. "Solution ALD" (sALD) can coat deep pores in a conformal manner.

Low-energy dc ion source for low operating pressure.

We report on an experimental study of an ion source based on a Penning discharge with a cold hollow cathode in crossed electric and magnetic fields. The minimum vacuum chamber operating pressure was 3 × 10(-5) Torr for argon and 5 × 10(-5) Torr for hydrogen. The use of a hollow cathode allowed decreasing the discharge operating voltage down to 350 V at a discharge current of ~100 mA.