I.B. Stepanov

Metal vapor vacuum arc ion sources ‘‘Raduga’’

A brief review is presented of the ‘‘Raduga’’ 1–4 repetitively pulsed metal vapor vacuum arc ion sources. Their operation principles and functional ranges are described. The Raduga ion sources provide single‐ and multi‐element implantation. These advantages are achieved by using not only pure single‐element or mixed ion fluxes, but also pulsed beam sequences with controllable composition and energy of each ion species. Another feature of the ion sources is their ability to generate a sequence of ion beam and plasma stream pulses. Switching between ion irradiation and plasma deposition can be done from pulse to pulse, within each pulse, or after accumulation of a required dose. Some specific features of the emission properties of broad beam metal vapor vacuum arc ion sources are described.

Vacuum arc ion and plasma source Raduga 5 for materials treatment

This article describes a new modification of high current ion and plasma source Raduga 5. A dc vacuum arc is used to generate plasma. Generation of accelerated ion beams is realized in the Raduga 5 in a repetitively pulsed mode with the pulse repetition rate up to 200 pps, the pulse duration up to 400 μs and the accelerating voltage up to 50 kV. To clean the vacuum arc plasma from the microparticle fraction of the products of the explosive cathode emission of the arc evaporator a new version of a straight-line plasma filter is used. This article describes a new version of the accelerating diode which works under conditions of high thermal loads with a continuous metal plasma flow and repetitively pulsed formation of an accelerated ion beams. A simultaneous generation of a metal plasma flow and pulse beams of accelerated ions in the Raduga 5 source ensures realization of the technologies of an ion assisted metal plasma deposition, ion implantation under ion sputtering compensation by metal plasma depositio...

Formation of intermetallic layers at high intensity ion implantation

The experimental results are presented on a study of intermetallic phase formation in the surface zone of metal target at high intensity ion implantation. High intensity ion implantation allow to obtain the surface-alloyed layers of a much greater thickness in comparison with ‘ordinary’ ion implantation. Pure polycrystalline nickel was chosen as the target. The nickel samples were irradiated with the aluminum ions using the vacuum-arc ion beam and plasma flow source ‘Raduga-5’. The RBS and TEM were used for the investigations presented. It was established that the fine dispersed intermetallic precipitates are formed in the surface alloyed nickel layer. The alloyed layer thickness is equal to 150 nm and more, while the ion projected range that is equal to 70 nm. Compositions of these intermetallic precipitates are close to Ni3Al and NiAl phases. The solid solution of aluminum in nickel is also formed. The depth dependence of the formation of intermetallic phases can be deduced from the Ni–Al phase diagram.

Very broad vacuum arc ion and plasma sources with extended large area cathodes

Two versions of vacuum arc sources for producing accelerated ion beams and plasma flows are described. The sources are distinguished by use of a dc vacuum arc discharge for plasma generation on the basis of a simple linear or coaxial plasma gun with extended large area (70 300 and 1500 cm2) cathodes and microparticle filtering system. The dc vacuum arc discharge combined with the diode extraction system enables us to use the single source for dc mode of plasma flow formation and repetitively pulsed mode of ion beam generation. Experimental and numerical results are presented on the repetitively pulsed accelerated ion beam formation in the vacuum arc sources with large area cathodes.

Plasma immersion ion charge state and mass spectrometer.

Investigation results of charge state of monocomponent plasma of Ti, Zr, W, and N, as well as that of multicomponent metal plasma of Ti/Zr (50/50 at.%) using plasma-immersion time-of-flight spectrometer are presented in the paper. The case of pressure impact in the working chamber on the ion charge state of combined metal (Ti) and gas-discharge (N) plasma is considered.

High current vacuum-arc ion source for ion implantation and coating deposition technologies

This work is devoted to the development and investigation of a high current ion source based on dc vacuum-arc plasma generation. Extraction and acceleration of ion beams are realized in a repetitively pulsed mode with the pulse repetition rate up to 200 pps, the pulse duration up to 400μs, the accelerating voltage up to 40 kV, and the pulsed ion-beam current up to 2 A. To remove microparticles from the vacuum-arc plasma a straight-line plasma filter is used. Examples of the source use for realization of high-intensity and high-concentration ion implantation regimes including those with formation of doped layers at depths that exceed ion projective range for more than an order of magnitude are presented. At the expense of change in order and intensity of ion and plasma material treatment, the advantage of application of one source for execution of material surface pretreatment and activation regimes, formation of wide transition layers between the substrate and coating, coating deposition, and high-intensi...

High-current vacuum-arc ion and plasma source "Raduga-5" application to intermetallic phase formation

Phase composition, structural state, and mechanical properties of the ion-doped surface layers of Ni, Ti, and Fe targets with Al and Ti ions implanted into using the metal ion beam and plasma source Raduga 5 have been investigated. The high-intensity mode of implantation allowed us to obtain the ion-doped layers with the thickness exceeding the ion projected range by several orders of magnitude. By the transmission electron microscopy, it has been found that the fine-dispersed equilibrium intermetallic phases (Me3Al, MeAl) and the solid solution of aluminum were formed in the doped Ni, Ti, and Fe surface layers at the depth of up to 2600nm. The maximum dopant concentration reached 75%. It has been shown that the average size of the formed phases was of 70nm. The microhardness of the different target surface layers increased by 1.5–3 times. The wear resistance of the samples did not change within the temperature range of 300–700K.

High current and high intensity pulsed ion-beam sources for combined treatment of materials

The complex installation for combined materials treatment with accelerated ion beams of different peak power and metallic plasma flows is described. The installation comprises the high-current repetitively pulsed vacuum arc ion source, high-intensity pulsed ion beam source, and direct-current vacuum arc plasma source combined with the plasma filter for plasma cleaning from the microparticle fraction. It has been found that the preliminary treatment of stainless steel samples with the high-power ion beam of nanosecond pulse duration results in the reduction of ion sputtering coefficient at the implantation of tungsten ions. It has been shown that the increase of maximum implanted tungsten concentration is influenced by changing the surface morphology and element structure of the samples affected by the high-power ion beam.

Research on materials surface layers element structure formation under combined treatment with pulsed ion beams of different powers

Abstract The investigation results are presented for some processes occurring at different stages of strong adhesion coating and modified layer creation with the use of high-dose implantation and deep diffusive doping of elements under pulsed energetic impact. The investigations have been carried out on installation, providing the possibility of combined materials treatment with pulsed ion beams of power density ranged from 10 3 to 10 8 W/cm 2 . The facility includes an accelerator of high-power ion beams and sources of repetitively-pulsed metal ion beams and metal plasma flows. The possibility of the application of a high power ion beam pulsed energetic impact to intensify mass transfer and increase the depth of doping for a preliminary implanted impurity has been demonstrated. The results are presented concerning the formation of high quality thin coatings with wide buffer layers determining their adhesive strength by means of the method of combined treatment using a high power ion beam.

Pseudo ribbon metal ion beam source.

The paper describes high broad metal ion source based on dc macroparticle filtered vacuum arc plasma generation with the dc ion-beam extraction. The possibility of formation of pseudo ribbon beam of metal ions with the parameters: ion beam length 0.6 m, ion current up to 0.2 A, accelerating voltage 40 kV, and ion energy up to 160 kV has been demonstrated. The pseudo ribbon ion beam is formed from dc vacuum arc plasma. The results of investigation of the vacuum arc evaporator ion-emission properties are presented. The influence of magnetic field strength near the cathode surface on the arc spot movement and ion-emission properties of vacuum-arc discharge for different cathode materials are determined. It was shown that vacuum-arc discharge stability can be reached when the magnetic field strength ranges from 40 to 70 G on the cathode surface.