CN118996352A

CN118996352A - WNiX sputtering target

Info

Publication number: CN118996352A
Application number: CN202310549498.6A
Authority: CN
Inventors: 托马斯·谢勒; 蔡永跃; 克里斯蒂安·林克; 亨里克·施密特; 孙毅
Original assignee: Plansee SE; Plansee (shanghai) High Performance Material Ltd
Current assignee: Plansee SE; Plansee (shanghai) High Performance Material Ltd
Priority date: 2023-05-16
Filing date: 2023-05-16
Publication date: 2024-11-22
Also published as: WO2024234934A1; TW202446971A

Abstract

The invention relates to a sputter target produced by a powder metallurgical method, comprising tungsten (W), nickel (Ni) and an additional metal X selected from the group comprising group 5 or group 6 of the periodic Table, and unavoidable impurities, wherein the sputter target has a two-phase microstructure, wherein one phase is pure W and the other phase is a mixed phase selected from the group comprising NiWX, niW, niX and mixtures thereof. The invention also relates to a method for producing WNiX sputter targets by the powder metallurgical route.

Description

WNiX sputter targets

Technical Field

The present invention relates to WNiX sputter targets produced by a powder metallurgical process, wherein X is selected from the group comprising group 5 or group 6 of the periodic table of the elements. The invention also relates to a method for producing WNiX sputter targets by a powder metallurgical process.

Background

Sputtering, also known as cathode atomization, is a physical process in which atoms are detached from a sputtering target and enter the gas phase by high energy ion bombardment.

Sputter targets, in particular NiWCr and NiWTa, consisting of Ni, W and optionally one or more other metals X, in particular selected from the group of refractory metals, are known in the prior art.

However, one problem with the prior art is that the use of nickel powder as a starting material for manufacturing the target results in the presence of pure nickel in the target that exhibits ferromagnetic properties. This means that a ferromagnetically pure Ni fraction or Ni phase appears in the microstructure of such sputter targets. Ferromagnetic properties are disadvantageous for magnetron sputtering, since they lead to different and unstable coating rates and thus have an adverse effect on the uniformity of the possible deposited layers to be formed. In the case of magnetron sputtering, a magnetic field is additionally generated in comparison with the abovementioned "simple" cathodic atomization. The superposition of the electric and magnetic fields lengthens the path of the charge carriers and increases the number of collisions per electron.

For example, EP3825427A1 relates to a sputter target comprising Ni, W and optionally one or more other metals X (e.g. Ti, V, cr, mn, zr, nb etc.) selected from refractory metals, sn, al and Si. In this application, the sputter target has a normalized peak intensity ratio of 0.40 or greater, which includes a pure Ni fraction.

CN104646930a relates to a method for manufacturing NiWCr alloy target, which comprises smelting, ingot casting, forging, primary heat treatment, hot rolling, cold rolling and secondary heat treatment. CN102534308a discloses NiWCr alloy targets with 15-35 wt% W and 5-15 wt% Cr composition. The material is also prepared by melting, casting, hot forging, cold rolling and recrystallization annealing steps. JP2010-133001A teaches a method of manufacturing a Ni alloy target containing 10 to 30 mass% of one or more selected from (Cr, mo, W) with the balance being Ni, wherein the target is obtained by melting, casting, plastic working, and recrystallization treatment. However, sputtering targets produced by melt metallurgy show the disadvantage of a coarse microstructure after the casting step, which leads to the formation of embossments by uneven erosion or cracks due to the brittleness of the coarse grain microstructure during sputtering. This problem can be solved by a powder metallurgy production process. Sputtering targets manufactured by powder metallurgy exhibit a very uniform fine-grained microstructure after sintering, which then ensures uniform erosion and optimized thin layers during sputtering. Although some of the above-mentioned patent applications mention fine and uniform grain sizes in the target, the grain sizes are achieved by an additional production step after casting.

WO2010/009829 discloses a sputter target made of a NiWCr alloy containing 1-20 at.% W and 1-20 at.% Cr, the remainder being Ni. The sputter target can be manufactured by casting or powder metallurgical production. However, this document does not mention the microstructure of the alloy target. Thus, it is not obvious whether pure Ni moieties are present in the microstructure of the sputter target.

JP2009-155722A teaches a sintered target containing 3 to 15 at% W, 20 at% or less Cr, the balance being Ni. The microstructure is described as a face-centered cubic structure. The present application provides a sputter target having greater than 15 atomic% W.

The sputtering targets described in the prior art do not meet increasing demands in terms of layer uniformity, uniformity of sputtering behavior, and avoidance of undesired localized partial melting. Localized partial melting is caused, for example, by an arcing process (localized formation of an arc).

Disclosure of Invention

It is an object of the present invention to provide a WNiX sputter target by means of which WNiX sputter target a layer can be produced which is very uniform both in terms of chemical composition and layer thickness distribution, wherein the microstructure does not contain a pure (or elemental) Ni phase. Furthermore, the sputtering target should have uniform sputtering behavior. Here, uniform sputtering behavior means that the individual phases in the microstructure of the sputtering target can be ablated at the same rate.

It is a further object of the present invention to provide a method of producing WNiX sputter targets having the above properties in a simple, reproducible and inexpensive manner.

This object is achieved by the independent claims. Advantageous embodiments are indicated in the dependent claims.

The sputtering target of the present invention comprises tungsten (W), nickel (Ni), one other metal X selected from the group consisting of group 5 or group 6 of the periodic table, and unavoidable impurities. The sputtering target has the following characteristics: the microstructure shows a two-phase microstructure, measured at the cross section of the target, wherein one phase is pure W (i.e. W grains) and the other phase is a mixed phase selected from the group comprising NiWX, niW, niX and mixtures thereof.

For the purposes of the present invention, "microstructure" means the microstructure of a sputter target, which can be analyzed in a simple manner familiar to the person skilled in the art by means of metallographic polished sections and evaluation under an optical microscope or a scanning electron microscope.

The presence of pure W phase as well as mixed phases in the sputter target according to the present invention can be very easily confirmed or excluded using JCPDS (joint committee on powder diffraction standards) card X-ray diffraction (XRD) taking into account the respective X-ray detection limits. By mixed phase is meant a phase that occurs in a binary or ternary component system, which is different from the pure elemental component used as the starting element. They generally have a crystal structure deviating from that of the pure component, and the mixed phase is characterized by a composition having a valence that is not precise (meaning that it does not directly correspond to the valence of the pure component).

The two-phase microstructure of the sputter target means that pure W phases and mixed phases occur, but other additional phases, such as oxides or voids, may also be present therein. However, the proportion of these further phases should be as small as possible, since they may have a negative effect on the sputtering behaviour, in particular on its uniformity. Therefore, the oxide can promote the occurrence of local initial melting (arc discharge), for example.

The presence of a mixed phase is not detrimental to the magnetic properties of the sputter target according to the present invention, since the Ni-containing phase, i.e. NiWX, niW or NiX, present in the WNiX system is not ferromagnetic.

The term "unavoidable impurities" refers to production-related contaminations with gases or accompanying elements, which originate from the raw materials used. In the sputtering target of the present invention, the ratio of these impurities is preferably 350. Mu.g/g (equivalent to ppm) or less for the gas (C, H, N, O), and 300. Mu.g/g or less for the other element (Al, ca, cd, cu, fe, K, li, mg, mn, na, P, pb, S, zr). Suitable methods of chemical element analysis are known to depend on the chemical element to be analyzed. The chemical analysis of the unavoidable impurities of the present invention is performed by performing thermal extraction analysis on the element O, N, H, or by performing combustion analysis on the element C, S, or using ICP-MS (inductively coupled plasma mass spectrometry) or ICP-OES (inductively coupled plasma emission spectroscopy).

Chemical analysis of the main components W, ni and X in the sputter target of the present invention was performed using XRF (X-ray fluorescence analysis).

In a preferred embodiment of the invention, the other metal X is a metal selected from the elements Cr, mo, nb or Ta, more preferably the other metal X is Cr or Ta.

In particular molybdenum, tungsten, tantalum, niobium and chromium, are advantageous for use as conductor tracks or lines. The low thermal expansion coefficient, in particular of molybdenum, tungsten, tantalum, niobium and chromium, ensures good adhesion and low layer stress of the deposited layer when deposited on the substrate.

Preferably, the sputter target according to the present invention contains 38-70 wt% W, 25-50 wt% Ni, 5-22 wt% X and the maximum proportion of unavoidable impurities is less than or equal to 650. Mu.g/g. It is apparent to those skilled in the art that the total amount of W+Ni+X+ impurities is 100 wt%. If the content of W is less than 38 wt%, a ferromagnetic Ni phase may be generated in the sputtering target. If the W content is higher than 70 wt%, the hardness of the target is too high so that optimal and economical workability can be ensured. The presence of a mixed phase consisting of NiWX phases, optional NiW phases, optional NiX phases or mixtures thereof is highly advantageous at the above-mentioned W content of 38-70 wt.%. The preferred composition of the sputter target comprises 40-67 wt% W, 26-46 wt% Ni, 6-21 wt% X. Preferably, the maximum proportion of unavoidable impurities according to the present invention is 300 μg/g or less. Also in this case, it is apparent that the total amount of w+ni+x+impurities is 100 wt%.

The sputter target according to the present invention preferably has a relative density of more than 85%. A relative density of greater than 90% is particularly advantageous. The density of the sputter target is highly dependent on the elemental X in the WNiX target, especially the O content in the elemental X powder. The higher the density of the target, the more advantageous its properties. Targets with low relative densities have a relatively high proportion of voids, which may be a source of actual leakage and/or impurities and particles during sputtering. In addition, targets with low densities tend to absorb water or other impurities, which can lead to process parameters that are difficult to control. Furthermore, during sputtering, the ablation rate of the material densified to only a low degree is lower than that of the material with the higher relative density.

As is known, absolute density can be readily determined by buoyancy methods using archimedes' principle. The relative density may be determined by, for example, a photomicrograph.

The sputter target according to the present invention preferably has an oxygen content of less than 350 μg/g, preferably less than 100 μg/g, more preferably less than 75 μg/g, even more preferably less than 30 μg/g. By having such a low oxygen content, unwanted arcing during sputtering can be reliably avoided.

The oxygen content can be determined in a simple manner by means of a thermal extraction analysis.

The sputter target according to the invention is characterized by a hardness after the pressing and sintering steps that is preferably lower than 400HV 10. It has been found that at a hardness of less than 400HV10, satisfactory toughness of the target can be optimally ensured. This simplifies handling during manufacturing, for example in an optional mechanical shaping step. Hardness of less than 400HV10 significantly simplifies handling during use, particularly as a one-piece tubular target in one embodiment. By performing one or more shaping steps after pressing and sintering, the hardness of the sputter target according to the present invention can be increased to 600HV10.

For the purposes of the present invention, the HV10 hardness (vickers) is the arithmetic mean determined from 5 hardness measurements.

The installation of sputter targets according to the invention in various coating apparatuses and the use thereof for coating substrates having different geometries place various geometric demands on the sputter targets according to the invention. Thus, this type of target may be in the form of a planar sputter target, such as a plate or disk, or a tubular sputter target. In addition, other target forms are within the scope of the invention, such as a rod or body having another complex shape.

The sputter target according to the present invention may be a multi-component sputter target or a single piece sputter target.

With regard to the design as a one-piece tubular sputter target, this enables a particularly uniform layer to be deposited on a large area substrate, since there are no discontinuities (e.g. joints, undercuts, residues of welding material, impurities in the joint area) between pieces (segments) of the target.

The design as a one-piece tubular target makes it possible to avoid that individual parts of the target move due to different temperatures or temperature cycles during the coating process, compared to a multi-part tubular target. Furthermore, the uniformity of the target material in terms of chemical purity or microstructure is better in the case of a one-piece tubular target than in the case of a multipart tubular target.

However, the sputter target according to the present invention can be configured not only as a one-piece tubular target. As described above, it may also exist as a multi-part tubular target, or have various regions of differing outer diameter or relative density over its length ("dog bone" target). Such embodiments can reduce or greatly avoid, for example, uneven ablation of the sputter target at the end of the target ("cross angle effect"). Targets having regions of different diameters may also be constructed as single piece targets and multi-piece targets.

The sputter target according to the present invention preferably has an area ratio of the W phase measured over the cross section of the target material of 5 to 50%, preferably 15 to 45%.

An area ratio of W phase less than 5% may be associated with an increase in the proportion of ferromagnetic Ni phase, thus resulting in poor sputtering behavior. The area ratio of the W phase exceeding 50% adversely affects the hardness and workability of the target.

The area ratio of the W phase was determined by appropriate evaluation of metallographic polished sections. The metallographic polished section is a two-dimensional section of the three-dimensional target. The area analysis can be performed on the micrographs produced in this way by commercially available image analysis software. This is done by image analysis (typically by comparing the phases to be distinguished) in order to determine the proportions of the individual phases in the microstructure described above. The average area ratio was calculated as the arithmetic average of 5 area ratio measurements measured on 5 image areas of 600 x 500 μm size of metallographic polished cross section, recorded at 200:1 magnification.

The sputter target according to the present invention preferably has an average particle size of the W phase of less than 40 μm, more preferably less than 30 μm.

The average grain size of the W phase is less than 40 μm, more preferably less than 30 μm, resulting in a particularly uniform sputtering behaviour and thus in the deposition of a particularly uniform layer having a particularly uniform thickness. Furthermore, the notch effect of the W phase is kept low in this way, with the result that a satisfactory toughness of the target is optimally ensured.

The diameter of the agglomerates of the plurality of grains of the W phase may exceed 40 μm, but in the sputter target of the present invention, these agglomerates cannot be considered as individual grains of the W phase.

The average grain size of the W phase can be determined in a simple manner on metallographic polished sections by the line section method shown for example in astm e 112-12.

A method according to the invention for manufacturing WNiX a sputter target by a powder metallurgical route is characterized in that the method comprises at least the following steps:

-a compacting step, in which the mixed powder of W powder, ni powder and X powder is compacted by applying pressure, heat or both pressure and heat to obtain a blank.

The compaction step as part of the method for manufacturing WNiX sputter targets according to the present invention results in compacting and densifying the appropriate powder mixture by applying pressure, heat, or both pressure and heat to form a blank. This can be done by various process steps, for example by pressing and sintering, cold isostatic pressing, hot pressing or Spark Plasma Sintering (SPS) or a combination of these methods or other methods of compacting the powder mixture.

The manufacture of the powder mixture usable in the method according to the invention is preferably achieved by mixing appropriate amounts of W powder, ni powder and X powder. These powders are filled into suitable mixing equipment and mixed until a uniform distribution of the individual components in the powder mixture is ensured. For the purposes of the present invention, the expression powder mixture may include prealloyed or partially alloyed powders containing components W, ni and X.

In a preferred embodiment, the mixing of the powders is carried out in an inert atmosphere, for example by using the inert gases argon or nitrogen.

The powder mixture produced in this way is preferably introduced into a mould to carry out the compaction step. Suitable moulds here are moulds of cold isostatic presses or flexible tubes, hot presses or moulds of spark plasma sintering devices, or capsule compartments in the case of hot isostatic pressing.

It has been found that in the method for manufacturing WNiX sputter targets according to the present invention, it is particularly advantageous to achieve the compaction step by sintering at a temperature of 1100 to 1450 ℃. Preferably, the sintering temperature is in the range 1250 to 1400 ℃. Here, sintering is a sintering method called pressureless sintering at a pressure of less than 2MPa, preferably at a pressure below atmospheric pressure.

Compaction at these temperatures optimally ensures that solid phase sintering or liquid phase sintering occurs to very high relative densities in the powder mixture present. At temperatures below 1100 ℃ compaction, the obtainable density may be too low, whereas at temperatures above 1450 ℃ a decrease in mechanical stability of the target may occur. In the case of compaction in the temperature range indicated, an optimal combination of high density and optimal mechanical properties is ensured which is achieved, and a low oxygen content can be achieved.

The sintering is advantageously carried out under vacuum, in an inert atmosphere and/or in a reducing atmosphere. For the purposes of the present invention, an inert atmosphere is a gaseous medium that does not react with the alloy constituents, such as a noble gas. Suitable reducing atmospheres are in particular hydrogen.

The blank obtained by the method according to the invention may then be subjected to a shaping step, possibly resulting in advantageous properties such as a further increase in density and/or a further homogenization of the microstructure. Suitable methods for carrying out the shaping step for the purposes of the present invention are, for example, rolling, extrusion and forging. Preferably, rolling or forging is used as a suitable shaping step.

The shaping step for the purposes of the present invention can be carried out as a single-stage or multistage process. Combinations of various suitable methods are also possible. Thus, the shaping process may comprise one or more sub-steps.

By a forming process comprising at least one forging step or rolling step, a defined degree of deformation can be introduced into the target in a particularly targeted manner. In this way, for example, excessive stiffening and thus exceeding the deformation forces that can be applied can be avoided.

By a shaping process comprising at least one rolling step or forging step, textures can be purposefully introduced into the target, and these textures in turn can exert a positive influence on the mechanical properties and sputtering properties of the target.

Furthermore, by using one or more rolling steps or forging steps, the thickness of the formed material over its length can be varied and set in a purposeful manner. This thickness can be used, inter alia, to improve the sputtering yield (regions of different outer diameters in length, "dog bone" targets).

Furthermore, by means of rolling, a uniform surface quality is obtained which facilitates further machining, and by forging or rolling, flatness and good roundness are obtained.

The method for manufacturing a sputter target according to the present invention may further comprise the steps of:

-heat treatment.

It is advantageous to heat treat the blank after compaction by pressure, heat or both, and after any shaping step. Depending on the chemical composition of the sputter target, the temperature employed may be in the range of 1000 to 1200 ℃. Moreover, the effect of such heat treatment may result from the exclusive dissipation of stress until the microstructure is altered by the movement of small-angle and/or large-angle grain boundaries.

It may be desirable or necessary to machine the obtained blank or target after the compaction step, after the optional shaping step or after the optional heat treatment step. Such mechanical treatment, for example by cutting, grinding or polishing, enables the final geometry to be set or made more accurate and, for example, a particularly desired surface quality to be set. These processing steps may be configured as dry or wet processing steps.

The sputter target produced by the method according to the invention can also be applied to one or more suitable support elements by means of, for example, a bonding step. Such a support element may be, for example, a backing plate of various geometries, or in the preferred case of a tubular sputter target, in particular a monolithic tubular target, may be a support tube or a support element that does not extend through the entire tube, such as a port, flange or other connecting means or a multi-part support tube or support element.

Such a support element may for example be made of stainless steel, cu, a Cu alloy, ti or a Ti alloy. However, other materials may be used to make such support elements.

For the bonding step, an element or alloy having a low melting point, such as indium, is preferably used. Furthermore, a binder, such as Ni, may optionally be used to ensure better wettability. Instead of the bonding step, the application to a suitable support element may also be performed by means of welding or adhesive bonding or by mechanical locking, for example by screwing or clamping.

In the method according to the invention for manufacturing WNiX a sputter target, as a further step, a corrosion-resistant protective device, for example in the form of a paint or varnish or in the form of a polymer coating, can also be applied to at least part of the inner diameter of the target.

Preferably, a sputtering target is produced by the method for producing WNiX sputtering target according to the present invention, which contains 38 to 70 wt% of W, 25 to 50 wt% of Ni, 5 to 22 wt% of X, and the maximum proportion of unavoidable impurities is 650. Mu.g/g or less. In this case, the use of the method according to the invention ensures that the microstructure of the WNiX sputter target has two phases, one of which is a pure W phase and the other of which is a mixed phase (measured by XRD) selected from NiWX, niW, niX and mixtures thereof.

The method for manufacturing a W-NiX sputter target according to the present invention makes it possible to ensure a relative density in WNiX sputter target manufactured by the method of more than 85%. In a particularly preferred embodiment of the invention, a relative density of greater than 90% may be obtained.

By the method according to the invention for manufacturing WNiX sputter targets, the purity and mechanical properties of the resulting target are also optimized.

Thus, the method of the invention results in a very low impurity content in the sputter target thus prepared, for example a preferred oxygen content of less than 350 μg/g, particularly preferably less than 100 μg/g, more preferably less than 75 μg/g, even more preferably less than 30 μg/g.

Preferably, a sputtering target containing 38 to 70 wt% W, 25 to 50 wt% Ni, 5 to 22 wt% X and unavoidable impurities is produced by means of the method for producing WNiX sputtering targets according to the present invention. In this case, a hardness of less than 400HV10 is preferably obtained by means of the method according to the invention after a compaction step, such as pressing and sintering.

Preferably, a sputtering target containing 38 to 70 wt% W, 25 to 50 wt% Ni, 5 to 22 wt% X and unavoidable impurities is produced by means of the method for producing WNiX sputtering targets according to the present invention. In this case, the area ratio of the W phase measured over the cross section of the target is up to 5% -50% by means of the method according to the invention.

Preferably, a sputtering target containing 38 to 70 wt% W, 25 to 50 wt% Ni, 5 to 22 wt% X and unavoidable impurities is produced by means of the method for producing WNiX sputtering targets according to the present invention. In this case, the average grain size of the W phase achieved by the method according to the present invention is less than 40. Mu.m, more preferably less than 30. Mu.m.

Drawings

The drawings show:

FIG. 1 is an X-ray diffraction pattern of WNiMo sputter target samples according to the present invention;

FIG. 2 is an X-ray diffraction pattern of WNiCr sputter target samples according to the present invention;

FIG. 3 is a microstructure (optical microscope) of WNiMo sputter targets according to the present invention;

fig. 4 is a microstructure (optical microscope) of WNiCr sputter targets according to the present invention.

Detailed Description

The invention is illustrated below with the aid of production examples and the accompanying drawings.

Examples

Example 1 (WNiMo tube manufacture):

The particle size of the W metal powder was 4. Mu.m, the particle size of the Ni metal powder was 4.2. Mu.m, and the particle size of the Mo metal powder was 4.6. Mu.m. The powder was added to a closed vessel in a ratio of 42 wt% W, 47 wt% Ni and 11 wt% Mo and mixed in a shaker for 1 hour.

A steel mandrel with a diameter of 141mm was placed in the middle of a rubber tube with a diameter of 300mm closed at one end. The powder mixture is introduced into the intermediate space between the steel core and the rubber wall and the rubber tube is closed at its open end by a rubber cap. The closed rubber tube was placed in a cold isostatic press and pressed under a pressure of 200MPa to give a disc-shaped green body having a relative density of about 59% and an outer diameter of 242 mm.

The green body produced in this way was sintered in an indirect sintering furnace at a temperature of about 1250 c in a hydrogen atmosphere. The relative density after sintering was about 80%.

The hardness of the target material is 126HV10. The oxygen content was found to be 190. Mu.g/g.

Fig. 1 shows the X-ray diffraction pattern of this example. For evaluation of the diffraction patterns, JCPDS cards 00-004-0806 (W) (corresponding to W phase), 01-071-9764 (Mo1.08Ni2.92), 01-072-2652 (Ni0.85W0.15) (corresponding to mixed phase) were used. As is evident from this figure, there is no pure Ni phase present in the X-ray spectrum (occurring at 2θ=44.5°). The peak at 2θ=40.2° refers to the pure W phase.

The microstructure is shown in fig. 3 as an optical microscope image. For optical microscopy images, a sample, such as a tube, is cut to about 15x15x15mm ³, then placed into an insert mold and filled with plastic particles. In the press, the granules are melted using pressure and temperature; after cooling, the samples were embedded in plastic. The surface to be inspected is then polished from coarse sand to fine grit with sandpaper and finally polished with a diamond suspension. The sample is then ready for examination directly under an optical microscope. The W grains (dark grey) are located in a mixture of NiWMo (bright colour). Black shows porosity due to fabrication by the powder metallurgical route.

Example 2 (WNiCr plate manufacture):

Also in this case, as raw materials, a W metal powder having a particle size of 4 μm as determined by the Fisher method, a Ni metal powder having a particle size of 4.2 μm as determined by the Fisher method, and a Cr metal powder (sieved to less than 45 μm) were used. The powder was introduced into a closed vessel in a ratio of 67 wt% W, 26 wt% Ni and 7 wt% Cr and mixed in a shaker for 1 hour.

The powder mixture was introduced into a flexible rubber tube which was closed at its open end by a rubber cap. The closed rubber tube was placed in a cold isostatic press and pressed at a pressure of 200MPa to give a green sheet with a relative density of about 64.9%.

The green body thus prepared was sintered in an indirect sintering furnace at about 1400 ℃ for 4 hours in a hydrogen atmosphere. The relative density after sintering was about 90%. The plate has approximate dimensions of 268 x 48.7 x 343mm ³. The hardness of the target material is 189HV10, and the oxygen content is 50 mug/g.

Fig. 2 shows the X-ray diffraction pattern of this example. For evaluation of diffraction patterns, JCPDS card 00-004-0806(W)、03-065-5108(Cr₄Ni₁₅W),01-071-7594(CrNi)、03-065-6291Cr₂Ni₃ and 01-077-3140 (Ni ₉ W) 0.4 were used. As is evident from this figure, there is no pure Ni phase present in the X-ray spectrum (occurring at 2θ=44.5°). The peak at 2θ=40.2° refers to the pure W phase.

The microstructure is shown in fig. 4 as an optical microscope image. Samples of the plate were prepared as described in example 1.

The W grains (dark grey) are located in a mixture of NiWCr (bright colour). Black shows porosity due to fabrication by the powder metallurgical route.

Claims

1. A sputter target manufactured by a powder metallurgical method, wherein said sputter target comprises tungsten (W), nickel (Ni) and one other metal X selected from the group comprising group 5 or group 6 of the periodic table, and unavoidable impurities, wherein said sputter target has a two-phase microstructure, wherein one phase is pure W and the other phase is a mixed phase selected from the group comprising NiWX, niW, niX and mixtures thereof.

2. The sputter target of claim 1, wherein the other metal X is a metal selected from the elements Cr, mo, nb, or Ta.

3. Sputter target according to claim 1 or 2, whereby said sputter target comprises the following composition: the maximum proportion of 38-70 wt% W, 25-50 wt% Ni, 5-22 wt% X, and unavoidable impurities is 650 μg/g or less, so that the sum of W+Ni+X+impurities is 100 wt%.

4. A sputter target according to any one of claims 1-3, whereby the density of the sputter target is at least 85%.

5. Sputter target according to any one of claims 1 to 4, characterised in that the oxygen content is less than 350 μg/g.

6. The sputter target of claim 5, wherein the oxygen content is less than 100 μg/g.

7. A sputter target according to any one of claims 1 to 6, characterised in that the sputter target is a tubular sputter target.

8. A sputter target according to any one of claims 1 to 6, characterised in that the sputter target is a planar sputter target.

9. Sputter target according to any one of claims 1 to 8, characterised in that the area ratio of the W-phase of the sputter target measured at the cross section of the target is 5-50%.

10. Sputter target according to any one of claims 1 to 9, characterised in that the average grain size of the W-phase of the sputter target is less than 40 μm.

11. A method of manufacturing WNiX a sputter target by a powder metallurgical process, said method comprising at least the steps of:

12. The method of manufacturing WNiX sputter targets of claim 11 wherein the compacting step is accomplished by sintering at a temperature of 1100 to 1450 ℃.

13. A method of manufacturing WNiX sputter targets according to claim 11 or 12, characterised in that the method comprises a shaping step after the pressing step.

14. The method of claim 13, wherein forming is performed by rolling or forging.

15. A method according to claim 13 or 14, wherein the shaping step is followed by a heat treatment.