Method for obtaining composite target for sputtering from tungsten-titanium-silicon alloy
SUBSTANCE: manufacturing method of composite target for obtaining films by magnetron sputtering and target obtained using the above method is proposed. Method involves manufacture of disc from polycrystalline titanium ingot obtained by multiple vacuum titanium re-melting, drilling of holes in staggered order in sputtered zone of titanium disc along two concentric circles and fixture of cylindrical inserts in them. Cylindrical inserts are made by cutting of ingots of monocrystalline tungsten and monocrystalline silicon, which have been obtained by multiple vacuum remelting of tungsten and silicon. Inserts attachment is performed by press fitting to drilled holes at the ratio of surface areas occupied with tungsten and silicon inserts on surface of target in titanium disc providing the production of films consisting of the following, wt %: silicon 0.1-1.3, titanium 11-33, and tungsten is the rest.
EFFECT: increasing thermal stability of metal coating and reproducibility of its formation process.
2 cl, 1 tbl, 1 ex
The invention relates to the production of atomized metal targets for microelectronics. In the production technology of very large scale integrated circuits (VLSI) silicon thin film of an alloy of tungsten and titanium are used as diffusion barrier layers between the silicon substrate and the metallization of aluminum alloys. Tungsten-titanium thin film barriers are made by spraying a tungsten-titanium target.
The prior art method of manufacturing a tungsten-titanium target for sputtering [RF Patent №2352684, 03.08.07], which includes multiple vacuum remelting of tungsten and titanium with obtaining a polycrystalline ingot of titanium and a single crystal, manufacture of polycrystalline ingot of the titanium disk, in which, in the spray zone, in two concentric circles in a checkerboard pattern drill holes and press fit attached to them cast cylindrical insert from a single crystal, previously subjected to grinding and cutting to length. This method of reception of targets have been severely tested in production and is well proven. However, the use of composite targets double quasiplane helped to identify a number of deficiencies in the tungsten-titanium film, which is directly the consequence of the physical nature of this difficult material - first of all, the relatively high level of mechanical stresses in the films, low resistance metallization and the lack of reproducibility of the technological process of forming metallization.
The objective of the invention is improving the heat resistance of the metallization and the reproducibility of the technological process of its formation.
DISCLOSURE of INVENTIONS
This is achieved in that in the method of manufacturing a composite target to obtain films by magnetron sputtering, comprising manufacturing a disk from an ingot of polycrystalline titanium, received multiple vacuum remelting of titanium, drilling holes in a checkerboard pattern in the spray zone of the titanium disk in two concentric circles and mount them in a cylindrical inserts, with a sharp tungsten ingots of monocrystalline and multicrystalline and monocrystalline silicon, received multiple vacuum remelting of tungsten and silicon, is made cylindrical insert and mount inserts provide press fit into the holes when the ratio of the areas occupied by the inserts of tungsten and silicon on the surface of the target in the titanium disk, providing films of the composition, wt.%: silicon 0,1-1,3, titanium 11-33, tungsten - rest. A composite target to obtain films magnetron spraying is by getting the specified method.
The IMPLEMENTATION of the INVENTION
The method is as follows. Is the vacuum remelting components such as titanium, silicon and tungsten. Titanium melt in electron-beam installation in a horizontal mould with getting a flat polycrystalline ingot in the form of a "pancake", which is subjected to machining to obtain a disk. In the titanium disk drill holes of a certain diameter to accommodate single-crystal inserts of tungsten and silicon. The original tungsten is subjected to electron-beam zone melting with obtaining single crystals of tungsten. Cylindrical rods of silicon and tungsten grinding on gauge length, resulting in a gain of cylindrical inserts that are pressed into holes in the titanium disk. Inserts of tungsten and silicon in the titanium disk is placed uniformly over the area of the spray. The ratio between the number of single-crystal inserts of tungsten and silicon drive titanium depends on the given contents of titanium, tungsten and silicon in the sputtered film. In exceptional cases, to maintain specified ratios in the sprayed film in the holes pressed inserts made of polycrystalline titanium, which allows to compensate for the lack of content in the film.
Films with silicon content less than 0.1 m is S.% though have satisfactory electrical performance, however, are characterized by relatively high levels of mechanical stress and a low resistance metallization. The silicon content higher than 1.3 wt.% leads to increased resistivity of the films.
An EXAMPLE of carrying out the INVENTION
A method of obtaining a composite of the target was carried out when applying the tungsten-silicon-titanium films with a given ratio of components. Thus the main task was to establish the optimal modes of atomization and the ratio of the elements in the diffusion contact barrier layers, which are characterized by the lowest mutual solubility on the border with aluminum metallization, high temperature resistance layer in combination with a low specific resistivity, good adhesion and optimum mechanical properties of the barrier layer. The basis of the target, which is a flat disc with a diameter of 190 mm, made of flat polycrystalline ingot of high purity titanium melted under vacuum in glucomannan water-cooled copper mold in electron-beam installation with an axial electron gun. The single crystals of tungsten with a diameter of 11.5 mm arbitrary crystallographic orientation were grown in vacuum apparatus for electron-beam zone melting with special annular electron gun with samisen the m ring cathode. Crystals of high-purity silicon received induction method with pulling from the melt. Before spark cutting single crystals of tungsten and silicon at length obtaining inserts have them grinding to a diameter of 11 mm, the Obtained insertion of single crystals of tungsten and silicon were pressed into holes in the titanium disk, and the number of inserts were selected according to a given ratio of the three components in the finish of the film. The deposition of the films was carried out on the installation magnetron sputtering with a magnetron source with a water-cooled electromagnet and a composite target with a diameter of 190 mm, the Tests were carried out on the alloys of titanium-tungsten and with varying silicon content, depending on the specified content of the three components in the film. Spraying conducted in argon under the following conditions: working pressure argon 5*10-1PA, the discharge current from 1.5 to 2.0 a, the voltage at the anode from 390 to 410, the current of the electromagnet 260 And magnetic induction 0,12 T.
Figure conductive elements of the alloy film on a silicon substrate with an oxidized surface, and the contact Windows were obtained when applying the film through precision free the mask of the molybdenum foil having a thickness of 50 μm, the obtained double-sided etching through the combined figure photoresistive film. Used the same standard photolithography process. For the first method of forming a pattern of the silicon wafer was heated in the process of applying the film to 140±10°C, and the second to 220-250°C. the Control of the elemental composition of the films was carried out on the electron microprobe analyzer, equipped with x-ray console. The thickness of the alloy films at the level of 0.15 μm was provided by analysis of the composition with an accuracy of ±1.5 percent.
Test samples with the contact barrier layers of the developed alloy was annealed in argon at a temperature of 550-575°C for 45 minutes Repeated cycles of annealing was performed on the pilot plant pulsed lamp annealing at the temperature limit of 600°C in argon. Analysis of samples from the results of repeated multiple annealing and source (after isothermal annealing of the samples was conducted in an optical microscope, and the condition of the contact layer after removing the metal film by etching. Similar conditions were made and tested samples with the contact-barrier layer of a binary alloy of titanium-tungsten. On the number of test samples had a p-n junction located at a depth of 0.35 μm, the reverse current IRwhich indirectly allows to judge about the safety barrier properties of the analyzed layer. Several test structures were performed prior to application of the platinum layer with a thickness of 0.1 μm and a subsequent heat treatment p and 400°C for 10 min in argon for forming studied under the contact-barrier layer a layer of platinum silicide. The results are shown in Table 1.
|The test results of alloy silicon-titanium-tungsten.|
|№ p/p||The composition of the alloy, wt.%||The number of cycles, it can withstand without changing more than 10%||Changing the p-n junction, %|
|Contact to n-Si||Contact to the p-Si|
|1||Silicon 0.1; titanium 11; tungsten 88,9||90-110||>100||<10|
|2||Silicon 0,4; titanium 27; tungsten 72,6||90-110||>100||<10|
|3*||Silicon 1,0; titanium 30; tungsten 69,0||>120||>120||<10|
|4*||Silicon 1,3; titanium 33; tungsten 65,7||>120||>120||5||Silicon 0,07; titanium 17; tungsten 82,93||30-40||40-50||40-45|
|6||Silicon 1,4; titanium 30; tungsten 68,6||40-50||50-55||35-40|
|7||Titanium 11; tungsten 89||30-40||35-45||95|
|8||Titan 30; tungsten 70||25-35||30-40||>100|
|*structures with silicide sublayer of silicon with a thickness of 0.1 μm|
From Table 1 it is evident that the best results were obtained for the ternary alloy of the proposed structure. High thermal stability characterized by a contact barrier layers with a sub-layer of platinum silicide. Thin films of ternary alloy of the optimal composition located on the p-n regions of silicon test structures have a significantly higher thermal stability and less impact on the p-n junction located under the contact window, than any of the binary alloys on the basis of the system is neither titanium-tungsten. Reproducibility process of forming a contact barrier layers was estimated by the change in the reverse current of the p-n junction. The reproducibility of the results for ternary alloys was the best.
Thus, a composite target and method of reception ensure the application of the contact barrier metallization layer of silicon integrated circuits, characterized by high thermal stability and a unique technological reproducibility of the process of its formation, which generally contributes to improving the quality of integrated circuits.
1. Method of manufacturing a composite target to obtain films by magnetron sputtering, comprising manufacturing a disk from an ingot of polycrystalline titanium, received multiple vacuum remelting of titanium, drilling holes in a checkerboard pattern in the spray zone of the titanium disk in two concentric circles and mount them in a cylindrical inserts, characterized in that the cutting of ingots of monocrystalline tungsten and monocrystalline silicon, received multiple vacuum remelting of tungsten and silicon, is made cylindrical insert and mount inserts provide press fit into the holes when the ratio of the areas occupied by the inserts of tungsten and silicon on the surface m is Sheni in the titanium disk, providing film composition, wt.%: silicon 0,1-1,3, titanium 11-33, tungsten - rest.
2. A composite target to obtain films by magnetron sputtering, characterized in that it is obtained by the method according to claim 1.
SUBSTANCE: invention relates to electronic engineering, particularly delay-line structures for O-type microwave devices with given filter properties. The delay-line structure has coil sections and an outer cylindrical metal housing. The outer cylindrical metal housing is placed coaxially with windings of the coil sections. The ends of the coil sections are closed by a support on the outer cylindrical metal housing. The ends of neighbouring coil sections are displaced from each other clockwise by an angle α whose value is selected using the relationship: where N=1, 2, 3… is the number of coil sections per period of the structure.
EFFECT: wider operating frequency band and functional capabilities.
SUBSTANCE: device to transmit microwave capacity at the E11 wave comprises coaxially arranged section of a round wave guide with a vacuum-tight soldered-in dielectric disc (DD) and two sections of rectangular wave guides connected to the section of the round wave guide at its opposite ends, and also one or two metal tubes (MT) for a cooling liquid. Each MT is placed in an appropriate slot arranged in DD along its diameter at one DD side. Each MT is installed along the appropriate slot and is soldered with its walls along the entire length. Ends of each MT are soldered to the wall of the round waveguide section in a vacuum-tight manner. The longitudinal axis of each MT lies in the place of the axial section of the round waveguide section arranged in parallel to wide walls of the rectangular waveguide sections.
EFFECT: improved heat removal from a dielectric disc of a jar window and higher level of average microwave capacity sent via a jar window.
4 cl, 2 dwg
SUBSTANCE: delay-line structure of spiral type contains metal frame with at least one spiral located at ends of dielectric supports. At least one metal ring with grooves with rigidly fixed free ends of dielectric supports is installed at frame concentrically in regard to spiral; the ring has possibility of translational movement along the system axis. At the ring there is also a tool for ring translation in the form of protrusion with threaded hole for connection with pin which ends are installed at grooves of housing flanges. In result of pins rotation metal rings are translated with spirals along longitudinal axis of delay-line structure. During spirals movement distance between them is changed and it leads to changes in operating frequency and delay coefficient of the structure. It allows adjustment of delay-line structure.
EFFECT: provision of structure adjustment.
2 cl, 1 dwg
SUBSTANCE: in the disclosed method, lamellae are made from monolithic copper material, where said lamellae have width and working gaps in between of up to 50 mcm, for which a fine-grained structure is formed from copper through equal channel angular pressing at a deformation rate of 0.4 mm/s at room temperature and with total number of pressing cycles equal to 8, with subsequent annealing at temperature of up to 150°C and holding for up to 1 hour to remove stress. Miniature high-precision periodic systems, having lamella thickness and working gaps in between of up to 50 mcm are made from spent copper through a combination of lathe machining and spark cutting.
EFFECT: high manufacturability of periodic systems of travelling-wave and backward-wave tubes, magnetrons and similar electrovacuum microwave devices in the millimetre and submillimetre wavelength range, while ensuring good output and operational parametres of the devices owing to reduction of wave loss increase in stability of their functioning.
2 cl, 3 dwg
SUBSTANCE: collector rocking method for controlling an electron beam (1) in a beam collector (230), particularly of a magnetic gyrotron device, includes steps for exposing the electron beam (1) to the effect of a transverse rocking field, having a field component which is perpendicular to the longitudinal direction (z) of the beam collector (230) and provides an inclined, rotating region (3) of intersection of the electron beam (1) in the beam collector (230), and variation of at least one of the longitudinal position and angle of inclination of the region (3) of intersection for modulation of the transverse rocking field. The invention also describes a collector rocking device (100) and a microwave oscillator (200).
EFFECT: reduced formation of maximum power.
14 cl, 7 dwg
SUBSTANCE: microwave energy output is proposed with a window of can type for high-capacity electronic instruments, comprising sections of rectangular wave guides, connected to coaxially-installed section of circular wave guide between them, having different internal and external diametres, cross section of which comprises a dielectric disc, tightly connected to its internal surface and isolating vacuum part, compensator element arranged on external surface of circular wave guide section and connected to it, conducting element for suppression of parasite resonances in the form of hollow cylinder, at least of two solid parts, differing by external diametre, arranged coaxially to section of circular wave guide, element for cooling, connected to section of circular wave guide, connecting flange directly adjacent to end surface of round wave guide section at non-vacuum side, at the same time geometric dimensions of round wave guide section, dielectric disc and conducting element for suppression of parasite resonances are set on the basis of specified parametres of microwave energy output.
EFFECT: increased output capacity, thermal-mechanical and electric strength of connections of microwave energy output elements.
4 cl, 1 dwg, 1 tbl, 10 ex
SUBSTANCE: system includes coaxial external and internal housings in the last one of which there installed is wave-guide structure, quarter-wave stubs each of which is formed with the conductor located between external and internal housings, and one end of which is connected through the pin to wave-guide structure, and the other one - to connection strap installed between external and internal housings. Wave-guide structure is made in the form of spiral; at that, each next place of connection of stubs to spiral relative to the previous one is offset through angle α clockwise and at the distance d along the spiral axis, and angle α and distance d shall be chosen from ratios: ; where N=1, 2, 3…, λ0 - length of wave in free space at central frequency of the specified working range.
EFFECT: enlarging the range of working frequencies of slow-wave system owing to coupling of several pass bands the number of which is determined with N number, and enlarging functional capabilities.
SUBSTANCE: invention relates to vacuum microwave devices, particularly to electron guns, and can be used in pulsed travelling-wave tubes or klystrons with low-voltage grid control of beam current. The electron gun contains a thoria cathode with annular emitting surface 1, shadow 2 and control 3 grids with discs 4 and 5 in their centres, anode 6 with an anode grid 7 with disc 8 in its centre, additional emitting surface 9 with a flat or spherical shape. Discs in the centres of the grids have openings 10, 11 and 12.
EFFECT: increased maximum power of the device, efficiency, reliability and durability due to increased beam perveance, improved focusing and current flow coefficient, achieved due to use of an additional emitting surface in the centre of the cathode, use of a disc in centre the anode grid and openings for transit of electrons to discs of the shadow, control and anode grids.
3 cl, 1 tbl, 12 dwg
SUBSTANCE: invention relates to non-ferrous metallurgy, namely to production of sputtering molybdenum targets and can be used in microelectronics to apply coatings by thin-film metallisation. The method involves a consistent deep vacuum refining by electron-beam remelting of a high-purity metal-ceramic bar obtaining monocrystalline or polycrystalline molybdenum. Whereupon a semi-finished target shaped as a monocrystalline or polycrystalline ingot is formed from the obtained product using electron-beam remelting in the horizontal or vertical mold. The ingot produced is then machined.
EFFECT: improved quality and reliability of the barrier and conducting films when sputtering cast high-purity molybdenum targets.
3 cl, 1 dwg, 1 ex
FIELD: physics, optics.
SUBSTANCE: invention is related to elements of focusing systems of electron-beam and SHF instruments with transverse-longitudinal interaction, and may be also used in accelerating equipment and electronic microscopy. Technical result is achieved by the fact that superhigh frequency multipole lens comprises resonator system that includes at least four electrodes connected serially as next nearest and installed symmetrically along circumference, coaxially to flow of charged particles passing inside. Electrodes of resonator system are arranged in the form of resonance sections of round metal rods with at least six symmetrically installed longitudinal grooves, width of which is equal to their depth and to quarter of slow wave length.
EFFECT: possibility to realise simultaneous focusing and prolonged interaction of beam with transverse-longitudinal electromagnet field and continuous power takeoff, which makes it possible to operated with broad bundles of charged particles.
SUBSTANCE: invention relates to production of thin films, particularly, to vacuum application of transparent conductive coatings by magnetron sputtering. Method for production of transparent conductive coatings of zinc oxide alloyed with helium on glass or polymeric substrate includes magnetron sputtering of cathode material consisting of zinc oxide alloyed with helium, sputtered material deposition on heated substrate with film forming on cathode material. Cathode sputtering is conducted in direct current argot atmosphere with unbalanced magnetic field of magnetron, which provides ion current density of 1 mA/cm2 and more on the substrate, with deposition performed on the substrate heated to the temperature of no more than 110°C. Unbalanced magnetic field of magnetron sputtering system is used.
EFFECT: electrophysical properties and homogeneity of distribution of coating electrophysical properties on a substrate at the temperature no more than 110°C.
SUBSTANCE: method includes installing at least one flat part on a carousel holder in a vacuum chamber, rotating the carousel and formation of a nanocomposite coating on a flat part with the help of sources of a sprayed material installed in the vacuum chamber. When the part passes in front of the source of the sprayed material, it is aligned with arrangement of a processed flat surface perpendicularly to the plane drawn via axes of carousel and holder rotation parallel to each other, and the part is fixed relative to the holder's axis. At the same time outside the area of the sprayed material deposition the part is turned by 180° relative to the holder's axis.
EFFECT: increased quality of a coating and homogeneity of its properties on the entire area of the processed surface of the flat part.
8 cl, 3 dwg
SUBSTANCE: in vacuum-arc device, analog control unit, switching device and additional ballast resistances the value of which determines cathode clearance current and heating current respectively are included.
EFFECT: providing stable fault-free operation of extended structure plasma source, thickness uniformity of coating formed on treated products, accelerated cathode entering into operational mode.
SUBSTANCE: method involves reactive magnetron sputtering of metal target from alloy of indium with stannum and deposition in working chamber of coating on dielectric substrate in atmosphere of mixture of gases, which contains inert gas and oxygen with ion enhancement of coating deposition process with ion flow; coating is deposited on polymer film at value of average density of current of magnetron discharge on sputtered target surface of 180-200 A/m2 and ion enhancement of coating deposition process with ion flow with energy of 20-40 eV in two stages: first in mixture of gases, which contains 20-22 vol. % of oxygen; then, in mixture of gases, which contains oxygen of not less than 60 vol. %, provided that t1:t2=2-3 ratio is fulfilled, where t1 - time for carrying out the first stage of coating deposition, t2 - time for carrying out the second stage of coating deposition.
EFFECT: use of the proposed method allows increasing service life of transparent electrodes in composition of electrochromic material, as well as improving reliability and life of optically active electrochromic glasing material.
1 tbl, 7 ex
SUBSTANCE: method includes application of a coating from titanium dioxide onto an item by the method of magnetron reactive DC sputtering of a titanium magnet in a mixture of argon and oxygen. Target sputtering is carried out under the total partial pressure of the mixture of 0.8-1.2 Pa, at the ratio of argon and oxygen in the mixture of 2/1, current density of 1.7-3.5 A/mm2 at the titanium target and the distance from the target to the substrate of 30-80 mm.
EFFECT: production of a coating with super-hydrophilic properties.
8 cl, 1 tbl, 1 ex
FIELD: process engineering.
SUBSTANCE: invention relates to method of razor blade formation. Proposed method comprises the following stages: fabricating substrate, producing wedge-like sharp edge on substrate with internal angle smaller than 30° and radius of rounding smaller than 1000 Å, placing said substrate into vacuum chamber, fitting first solid target into said chamber, feeding gas therein to ionise and generate ion flow from said first solid target by applying pulses of negative voltage to first solid target. This makes ions make thin-film coat of aforesaid sharp edges.
EFFECT: higher quality and durability.
17 cl, 6 dwg
FIELD: machine building.
SUBSTANCE: substrate holder consists of at least one module containing at least one head with elements of substrates fixation connected with drive and set by means of carriers on base. Carriers are transferred into one of fixed positions of waiting or processing. Treated surfaces of substrates are arranged along normal to vector of sputtered material flow. A platform of the installation is made in form of a hollow circular cylinder which under automatic mode facilitates cyclic setting travels of the substrate holders by means of mechanisms of their drive from one position of processing to another at angle α=2π/n, where n is number of processing positions. The cases of the substrate holders with mechanisms of their transfer and time control sensors are arranged on a special stage inside the platform under an aperture. The stages have guides rigidly secured beneath plane of overlap along boundaries of apertures in the direction from periphery to centre of the platform and two stops. A stationary stop is mounted on an internal surrounding frame of the platform. A flap stop is mounted on the internal surrounding frame of the platform with a lock.
EFFECT: raised efficiency, flexibility, resource saving, serviceability and quality of settled layer.
10 cl, 9 dwg
SUBSTANCE: procedure consists in ion-plasma sputtering target made of complex oxides of ferroelectric and in application of its atoms on substrate arranged on anode. Also, a cylinder screen made of dielectric material is set between the substrate and target. A sputtered target can be made of BaxSr1-xTiO3 or PbZrxTi1-xO3.
EFFECT: expanded range of deviation of stoichiometric composition of produced films from stoichiometric composition of sputtered target.
3 cl, 4 dwg
SUBSTANCE: to pre-cleaned surface of the substrate there applied are layers of coating by means of magnetron sputtering; at that, first, titanium adhesion layer is applied by magnetron sputtering of titanium target in inert gas; then, titanium nitride TiN layer is applied by sputtering of titanium target in gas mixture of inert and reaction gases; after that, alternating layers of two-component zirconium nitride ZrN are applied by sputtering of zirconium target in gas mixture of inert and reaction gases and zirconium by sputtering of zirconium target in inert gas. Then, alternating layers of three-component titanium and zirconium nitride TiZrN are applied by simultaneous sputtering of titanium and zirconium targets in gas mixture of inert and reaction gases and zirconium by sputtering of zirconium target in inert gas.
EFFECT: mutual location of layers in the coating provides minimum heat stresses at boundaries of layers and it is the most favourable from the point of view of coating material fatigue strength at action of dynamic thermal power loads at operation under conditions of increased temperatures.
SUBSTANCE: substrate is put into the chamber of an apparatus fitted with a magnetron sputtering device, an electric-arc evaporator and a resistance heater. The surface of the substrate is cleaned in glow discharge with non-contact heating of the surface using the resistance heater to temperature 100°C and ionic cleaning is carried using the electric-arc evaporator in an inert gas medium while heating the surface to temperature 300°…350°C. A titanium base layer is then deposited on the substrate through electric-arc evaporation of a titanium cathode in an inert gas medium and alternating layers from two-component titanium nitride and three-component aluminium and titanium nitride are deposited in a gaseous mixture of inert and reaction gases. The titanium nitride layer is deposited first and the aluminium and titanium nitride layer is deposited last. The titanium nitride layers are obtained via magnetron sputtering of a titanium target, and the aluminium and titanium nitride layers are obtained via simultaneous electric-arc evaporation of an aluminium cathode and magnetron sputtering of a titanium target.
EFFECT: high wear-, impact-, thermal-, crack- and corrosion-resistance of the processed surface.
SUBSTANCE: powders of tungsten and tantalum are mixed and rods are manufactured by hydrostatic extrusion of the mixture at a pressure of 140÷160 MPa for 3÷5 minutes. Then the rods are heat treated in vacuum with residual pressure of P≤8·10-3 Pa at a temperature of 800 °C. Then the rods are continued to be processed in a reducing atmosphere at a surplus pressure of at least 0.2 atm and a temperature of 800÷1000 °C for not less than two hours. Then the rods are heat treated in vacuum with residual pressure of P≤8·10-3 Pa at a temperature of T≥1500°C for not less than 2 hours followed by cooling. Heating and cooling under vacuum and the reducing atmosphere are carried out at a rate of 300÷400 °C/h. A mono-crystal bar is grown by crucibleless melting by means of cathode ray heating it is finished by even heat with seed melting to the end of the bar of odd heat.
EFFECT: production of mono-crystals of tungsten tantalum alloy with a high degree of uniformity of distribution of tantalum along the bar.
3 cl, 1 tbl