WNiX Sputtering Target

Abstract

The present invention relates to a sputtering target manufactured by powder metallurgy comprising tungsten (W), nickel (Ni), and one other metal X selected from the group consisting of group 5 or 6 of the periodic table, as well as unavoidable impurities, wherein the sputtering target has a two-phase microstructure, one phase being pure W and the other phase being a mixed phase selected from the group consisting of NiWX, NiW, NiX, and mixtures thereof. The present invention further relates to a method for manufacturing a WNiX sputtering target by powder metallurgy.

Description

Technical Field

[0001] The present invention relates to a WNiX sputtering target manufactured by powder metallurgy, where X is selected from the group consisting of Group 5 or Group 6 of the periodic table. The present invention further relates to a method for manufacturing a WNiX sputtering target by powder metallurgy.

Background Art

[0002] Sputtering, also called cathode atomization, is a physical process in which atoms are separated from a sputtering target by impact with high-energy ions and move into the gas phase.

[0003] Sputtering targets composed of Ni, W, and optionally one or more additional metals X selected especially from the group of refractory metals, particularly NiWCr and NiWTa, are already known from the prior art.

[0004] However, the problem with the prior art is that using Ni powder as a starting material for making the target results in the presence of pure nickel, which exhibits ferromagnetism, in the target material. This means that in the microstructure of such sputtering targets, a ferromagnetic pure Ni fraction or Ni phase occurs. Ferromagnetic properties lead to different unstable coating rates and thus have an adverse effect on the homogeneity of the deposited layer that can be formed, which is disadvantageous for magnetron sputtering. In the case of magnetron sputtering, compared to the above-mentioned "simple" cathode sputtering, a magnetic field is further generated. The superposition of the electric field and the magnetic field lengthens the path of the charge carriers and increases the number of collisions per electron.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

[0006] For example, EP 3 825 427 A1 relates to a sputtering target comprising Ni, W, and optionally one or more further metals X selected from the group consisting of refractory metals (e.g., Ti, V, Cr, Mn, Zr, Nb, etc.), Sn, Al, and Si. In this application, the sputtering target contains a fraction of pure Ni and has a normalized peak intensity ratio of 0.40 or higher.

[0007] CN 104 646 930 A relates to a method for manufacturing a NiWCr alloy target comprising the steps of melting, casting, forging, primary heat treatment, hot rolling, cold rolling, and secondary heat treatment. CN 102 534 308 A discloses a NiWCr alloy target having a composition of 15-35 wt% W and 5-15 wt% Cr. This material is also prepared by the steps of melting, casting, hot forging, cold rolling, and recrystallization annealing. Japanese Patent Publication No. 2010-133001 teaches a method for manufacturing a Ni alloy target containing 10-30 mass% of one or more selected from (Cr, Mo, W) with the remainder being Ni, and this target is obtained by melting, casting, plastic working, and recrystallization treatment. However, sputtering targets manufactured by molten metallurgy exhibit the drawback of a rough microstructure after the casting process, resulting in relief formation in the sputtering process due to non-uniform erosion. This problem can be overcome by the powder metallurgy manufacturing route. Sputtering targets manufactured by powder metallurgy exhibit a very homogeneous fine grain microstructure after sintering, which then ensures homogeneous erosion during the sputtering process and results in an optimized thin layer. Some of the aforementioned patent applications refer to fine and uniform particle size in the target, which is achieved by an additional manufacturing step after casting.

[0008] International Publication No. 2010 / 009829 discloses a sputtering target made of a NiWCr alloy containing 1-20 atomic% W, 1-20 atomic% Cr, and the remainder Ni. This sputtering target can be manufactured by casting or by powder metallurgy production. However, this document does not mention the microstructure of the alloy target. Therefore, it is not clear whether a proportion of pure Ni is present in the microstructure of the sputtering target.

[0009] Japanese Patent Publication No. 2009-155722 discloses a sintered target material containing 3 to 15 at.%W, 20 at.%Cr or less, with the remainder being Ni. The microstructure is described as a face-centered cubic structure. This application provides a sputtering target with a W exceeding 15 at.%W.

[0010] The sputtering targets described in the prior art fail to meet the increasing demands regarding layer homogeneity, homogeneity of sputtering behavior, and avoidance of undesirable localized partial melting. Localized partial melting is caused, for example, by arcing (localized formation of an electric arc). [Overview of the project]

[0011] The object of the present invention is to provide a WNiX sputtering target that can produce a highly homogeneous layer in terms of both chemical composition and layer thickness distribution, and whose microstructure does not contain a pure (or basic) 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.

[0012] A further object of the present invention is to provide a simple, reproducible, and inexpensive manufacturing route for producing a WNiX sputtering target having the above-described properties.

[0013] This objective is achieved by the independent claim. Advantageous embodiments are shown in the dependent claims. [Means for solving the problem]

[0014] The sputtering target according to the present invention comprises tungsten (W), nickel (Ni), one further metal X selected from the group consisting of Group 5 or Group 6 of the periodic table, and unavoidable impurities. The microstructure is characterized by exhibiting a two-phase microstructure in which one phase is pure W (i.e., W particles) and the other phase is a mixed phase selected from the group consisting of NiWX, NiW, NiX and mixtures thereof, as measured in the cross section of the target material.

[0015] For the purposes of this invention, "microstructure" means the microstructure of a sputtering target, which can be analyzed by those skilled in the art by a simple method of evaluation under an optical microscope or scanning electron microscope with the help of a metal polished section.

[0016] The generation of pure W phase and mixed phase in the sputtering target according to the present invention can be very easily confirmed or excluded by X-ray diffraction (XRD) using JCPDS (Joint Committee on Powder Diffraction Standards) cards (considering the respective X-ray detection limits). A mixed phase refers to a phase that occurs in a two- or three-component phase diagram, different from the pure components used as starting elements. They often have a crystal structure that deviates from the crystal structure of the pure components, and mixed phases are characterized by a composition with inaccurate valencies (meaning they do not directly correspond to the valencies of the pure components).

[0017] The two-phase microstructure of a sputtering target refers to the generation of a pure W phase and a mixed phase, but further phases such as oxides or pores can also be present. However, the proportion of such further phases should be kept as low as possible, as they can adversely affect the sputtering behavior, particularly its homogeneity. For example, oxides can promote the generation of localized initial melting (arc discharge).

[0018] The generation of the mixed phase is not disadvantageous with respect to the magnetic properties of the sputtering target according to the present invention because the Ni-containing phases that occur in the WNiX system, namely NiWX, NiW or NiX, are not ferromagnetic.

[0019] The term "inevitable impurities" refers to production-related contamination by gases or accompanying elements derived from the raw materials used. The proportion of such impurities in the sputtering target according to the present invention is preferably less than 350 μg / g (equivalent to ppm) for gases (C, H, N, O) and less than 300 μg / g for other elements (for example, Al, Ca, Cd, Cu, Fe, K, Li, Mg, Mn, Na, P, Pb, S, Zr). Appropriate methods for chemical element analysis are known to depend on the chemical elements to be analyzed. The chemical analysis of the inevitable impurities according to the present invention was carried out by thermal extraction analysis of the elements O, N and H, or by combustion analysis of the elements C and S, or by using ICP-MS (inductively coupled plasma mass spectrometry) or ICP-OES (emission spectrometry using inductively coupled plasma).

[0020] The chemical analysis of the main components W, Ni and X in the sputtering target material according to the present invention was carried out using XRF (X-ray fluorescence analysis).

[0021] In a preferred embodiment of the present invention, the other metal X is one metal selected from the elements Cr, Mo, Nb or Ta, and more preferably, the other metal X is Cr or Ta.

[0022] In particular, the high electrical conductivity of molybdenum, tungsten, tantalum, niobium and chromium is advantageous for use as conductor paths. The low thermal expansion coefficients, particularly those of molybdenum, tungsten, tantalum, niobium and chromium, ensure good adhesion of the layer and low layer stress when deposited on a substrate.

[0023] Preferably, the sputtering target according to the present invention contains 38 to 70% by weight of W, 25 to 50% by weight of Ni, 5 to 22% by weight of X, and a maximum proportion of unavoidable impurities of 650 μg / g or less. It is obvious to those skilled in the art that the total of W + Ni + X + impurities is 100% by weight. If the amount of W is less than 38 wt%, a ferromagnetic Ni phase may occur in the sputtering target. If the W content exceeds 70% by weight, the hardness of the target material becomes too high to ensure optimal and economical workability. With the above W content of 38 to 70% by weight, the presence of a mixed phase composed of a NiWX phase, optionally a NiW phase, optionally a NiX phase or optionally a mixture thereof is very advantageous. A preferred composition of the sputtering target contains 40 to 67% by weight of W, 26 to 46% by weight of Ni, and 6 to 21% by weight of X. Preferably, the maximum proportion of unavoidable impurities according to the present invention is ≤ 300 μg / g. Also in this case, it is obvious that the total of W + Ni + X + impurities is 100% by weight.

[0024] The sputtering target according to the present invention preferably has a relative density exceeding 85%. A relative density exceeding 90% is particularly advantageous. The density of the sputtering target greatly depends on the element X in the WNiX target, particularly the O content in the powder of the element X. The higher the density of the target, the more advantageous its properties. A target with a low relative density has a relatively high proportion of pores that can serve as a substantial source of leakage and / or impurities and particles during the sputtering process. Furthermore, a target with a low density tends to absorb water or other impurities, which can lead to process parameters that are difficult to control. In addition, during the sputtering process, the ablation rate of a material with a slightly higher density is lower than that of a material with a relatively high density.

[0025] As is known, the absolute density can be easily determined by the buoyancy method using Archimedes' principle. The relative density can be determined, for example, by micrographs.

[0026] The sputtering target according to the present invention preferably has an oxygen content of less than 350 μg / g, more preferably less than 100 μg / g, more preferably less than 75 μg / g, and even more preferably less than 30 μg / g. Having such a low oxygen content ensures that undesirable arcing during sputtering can be reliably avoided.

[0027] The oxygen content can be determined by a simple method using thermal extraction analysis.

[0028] The sputtering target according to the present invention is preferably characterized by a hardness of less than 400 HV10 after the pressing and sintering steps. It has been found that sufficient toughness of the target material can be optimally ensured at a hardness of less than 400 HV10. This simplifies handling during the manufacturing process, for example, during any mechanical forming steps. In use, particularly as a one-piece tubular target in one embodiment, a hardness of less than 400 HV10 significantly simplifies handling. The hardness of the sputtering target according to the present invention can be increased up to 600 HV10 by performing one or more forming steps after pressing and sintering.

[0029] The hardness of HV10 (Vickers hardness) is the arithmetic mean determined from five hardness measurements for the purposes of this invention.

[0030] The installation of sputtering targets according to the present invention in various coating plants, and for coating substrates having different geometric shapes, imposes various geometric requirements on the sputtering targets according to the present invention. Therefore, this type of target can take the form of a flat sputtering target, for example, a plate or a disk, or a tubular sputtering target. Additional target forms, such as rods or bodies having other complex shapes, may also be within the scope of the present invention.

[0031] The sputtering target according to the present invention may be a multipart sputtering target or a one-piece sputtering target.

[0032] Regarding the design as a one-piece tubular sputtering target, this allows for the deposition of a particularly uniform layer on a large-area substrate because there are no discontinuities (e.g., joints, undercuts, solder residue, impurities in the joint area) between the individual pieces (segments) of the target.

[0033] Designing a target as a single, integrated tubular target, in contrast to a multi-part tubular target, allows for avoidance of shifts in individual target pieces due to different temperatures or temperature cycles during the coating process. Furthermore, the uniformity of the target material in terms of chemical purity or microstructure is better with a one-piece tubular target than with a multi-part tubular target.

[0034] However, the sputtering target according to the present invention can not only be configured as a single tubular target. As already mentioned above, it can also exist as a multi-part tubular target, or it can have various regions with different outer diameters or relative densities along its length ("dogbone" target). Such embodiments make it possible to reduce or significantly avoid, for example, uneven ablation of the sputtering target at the edges of the target material ("section corner effect"). Targets with regions of different diameters can also be constructed as a single part and as a multi-part target.

[0035] The sputtering target according to the present invention preferably has an area ratio of the W phase measured in the cross-section of the target material, in the range of 5% to 50%, preferably 15% to 45%.

[0036] If the area ratio of the W phase is less than 5%, the proportion of the ferromagnetic Ni phase increases, resulting in poor sputtering behavior. If the area ratio of the W phase exceeds 50%, it may adversely affect the hardness and processability of the target material.

[0037] The area proportion of the W phase is determined by a proper evaluation of the polished metal section. The polished metal section is a two-dimensional section of the three-dimensional target material. Region analysis can be performed on the micrographs thus produced using commercially available image analysis software. This is performed by image analysis, typically by contrasting identified phases, to determine the proportion of individual phases in the microstructure described above. The average area proportion is calculated as the arithmetic mean of five measurements of the area proportion measured in five image regions of the polished metal section, each having a size of 600 × 500 μm, recorded at a magnification of 200:1.

[0038] The sputtering target according to the present invention preferably has an average particle size of W phase of less than 40 μm, more preferably less than 30 μm.

[0039] An average particle size of the W phase of less than 40 μm, more preferably less than 30 μm, results in particularly uniform sputtering behavior, and therefore, the deposition of a particularly uniform layer with particularly uniform thickness. In addition, the notch effect of the W phase is suppressed in this way, and as a result, good toughness of the target material is optimally ensured.

[0040] Although aggregates of multiple W-phase particles can exceed a diameter of 40 μm, such aggregates are not considered to be individual W-phase particles in the sputtering target according to the present invention.

[0041] The average grain size of the W phase can be easily determined by the line section method on a metal-polished cross section, for example, as shown in ASTM E112-12.

[0042] The method according to the present invention for manufacturing a WNiX sputtering target via a powder metallurgy pathway includes at least the following steps: A blank is obtained by a compaction process in which a mixture of W powder, Ni powder, and X powder is pressurized, heated, or pressurized and heated to compact the mixture. It is characterized by including.

[0043] The compression process, as part of the method according to the present invention for manufacturing WNiX sputtering targets, involves compressing a suitable powder mixture and applying pressure, heat, or both pressure and heat to compress it and form a blank. This can be done by various process steps, such as pressing and sintering, cold isostatic pressing, hot isostatic pressing, hot pressing, or spark plasma sintering (SPS), or a combination of these methods, or by further methods for compressing the powder mixture.

[0044] The production of a powder mixture that can be used in the method according to the present invention is preferably achieved by mixing appropriate amounts of W powder, Ni powder, and X powder. These powders are filled into a suitable mixing apparatus and mixed until a uniform distribution of the components in the powder mixture is ensured. For the purposes of the present invention, the resulting powder mixture may include pre-alloyed or partially-alloyed powders containing the components W, Ni, and X.

[0045] In a preferred embodiment, the powders are mixed in an inert atmosphere, for example, using an inert gas such as argon or nitrogen.

[0046] The powder mixture thus produced is preferably introduced into a mold to carry out a compression process. Here, a suitable mold is a die or flexible tube for a cold isostatic press, a die for a hot press or spark plasma sintering plant, or a can in the case of a hot isostatic press.

[0047] In the method according to the present invention for manufacturing WNiX sputtering targets, it has been found that compression treatment by sintering at a temperature of 1100 to 1450°C is particularly advantageous. Preferably, the sintering temperature is in the range of 1250 to 1400°C. Here, the sintering is a sintering process called pressureless sintering at a pressure of less than 2 MPa, preferably less than atmospheric pressure.

[0048] Compression at these temperatures optimally ensures that solid-phase or liquid-phase sintering occurs to a very high relative density in the present powder mixture. Compression below 1100°C results in densities that are too low, while temperatures above 1450°C can lead to a decrease in the mechanical stability of the target material. Compression within the indicated temperature range ensures an optimal combination of high achieved density and optimal mechanical properties, and allows for the achievement of low oxygen content.

[0049] Sintering is advantageously carried out under vacuum, in an inert atmosphere, and / or a reducing atmosphere. For this purpose, the inert atmosphere is a gaseous medium that does not react with the alloy components, such as a noble gas. A preferred reducing atmosphere is hydrogen in particular.

[0050] The blanks obtained by the method according to the present invention can then be subjected to a forming process to produce advantageous properties, such as a further increase in the density of the microstructure and / or further homogenization. Suitable methods for carrying out the forming process for the purposes of the present invention are, for example, rolling, extrusion, and forging. Rolling or forging is preferred as the forming process.

[0051] The forming process for the purposes of the present invention can be carried out as a single-step or multi-step process. A combination of several suitable processes is also possible. Therefore, the forming process may include one or more substeps.

[0052] A predetermined degree of deformation can be introduced into the target material in a particularly intentional manner by a forming process that includes at least one forging or rolling step. In this way, for example, excessive strengthening and, consequently, exceeding the deformable force that can be applied can be avoided.

[0053] Textures can be introduced into a target material in an intentional manner by a forming process that includes at least one rolling or forging step, and these can have a positive effect on both the mechanical and sputtering properties of the target material.

[0054] Furthermore, by using one or more rolling or forging steps, it becomes possible to vary the thickness of the formed material over its length and to set this thickness in an intentional manner. The thickness can be used, in particular, to increase the sputtering yield (regions with different outer diameters over their length, "dogbone" targets).

[0055] Furthermore, rolling makes it possible to achieve a uniform surface quality that is advantageous for further mechanical processing, and straightness and good roundness can be achieved by forging or rolling.

[0056] The method for manufacturing a sputtering target according to the present invention may further include the following steps: heat treatment;

[0057] Heat treatment of the blank may be advantageous both after compression by pressure, heat, or both pressure and heat, and after any molding step has been performed. Depending on the chemical composition of the sputtering target, the temperature used may be in the range of 1000-1200°C. Furthermore, the effects of such heat treatment can range from the exclusive release of stress to changes in microstructure through the movement of small-angle and / or large-angle grain boundaries.

[0058] Mechanical treatment of the resulting blank or target material may be desirable or required after the compression step, after any forming step, or after any heat treatment step. Such mechanical treatment, such as cutting, grinding, or polishing, makes it possible to more precisely define the final shape and, for example, to set a specific desired surface quality. These treatment steps can be configured as dry or wet treatment steps.

[0059] A sputtering target manufactured by the method according to the present invention can also be applied to one or more suitable support elements by, for example, a joining step. Such support elements may be, for example, backing plates of various shapes, or, in the case of a tubular sputtering target, particularly a one-piece tubular target, a support tube, or a support element that does not penetrate the entire tube, such as a port, flange, or other connecting part, or a multi-part support tube or element.

[0060] Such support elements can be made from, for example, stainless steel, Cu, Cu alloys, Ti, or Ti alloys. However, other materials can also be used to manufacture such support elements.

[0061] For the bonding process, it is preferable to use an element or alloy with a low melting point, such as indium. Furthermore, a binder, such as Ni, may optionally be used to ensure better wettability. Instead of the bonding step, application to a suitable support element may also be performed by soldering or adhesive bonding, or by mechanical locking, such as by screwing or clamping.

[0062] In the method according to the present invention for manufacturing a WNiX sputtering target, it is also possible to apply a corrosion-resistant protective means, for example in the form of a paint or varnish or a polymer coating, to at least a portion of the inner diameter of the target material.

[0063] Preferably, a sputtering target containing 38-70% by weight of W, 25-50% by weight of Ni, 5-22% by weight of X, and a maximum proportion of unavoidable impurities of 650 μg / g or less is produced by the method according to the present invention for producing a WNiX sputtering target. In this case, the processing of the method according to the present invention ensures that the microstructure of the WNiX sputtering target has two phases, one phase being a pure W phase and the other phase being a mixed phase selected from the group consisting of NiWX, NiW, NiX, and mixtures thereof (measured by XRD).

[0064] The method according to the present invention for manufacturing a W-NiX sputtering target makes it possible to guarantee a relative density of more than 85% in the WNiX sputtering target manufactured by this method. In a particularly preferred embodiment of the present invention, a relative density of more than 90% can be achieved.

[0065] The purity and mechanical properties of the obtained target material are also optimized by the method according to the present invention for manufacturing WNiX sputtering targets. Therefore, the method according to the present invention results in a very low content of impurities in the sputtering target produced thereby, 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, and even more preferably less than 30 μg / g.

[0066] Preferably, a sputtering target containing 38-70% by weight of W, 25-50% by weight of Ni, 5-22% by weight of X and unavoidable impurities is manufactured by the method according to the present invention for manufacturing a WNiX sputtering target. In this case, a hardness of less than 400 HV10 is preferably achieved by the method according to the present invention after a compression step, e.g., pressing and sintering.

[0067] Preferably, a sputtering target containing 38-70% by weight of W, 25-50% by weight of Ni, 5-22% by weight of X, and unavoidable impurities is manufactured by the method according to the present invention for producing a WNiX sputtering target. In this case, the proportion of the W phase area measured in the cross-section of the target material in the range of 5%-50% is achieved by the method according to the present invention.

[0068] Preferably, a sputtering target containing 38-70% by weight of W, 25-50% by weight of Ni, 5-22% by weight of X, and unavoidable impurities is produced by the method according to the present invention for producing a WNiX sputtering target. In this case, an average particle size of the W phase of less than 40 μm, more preferably less than 30 μm, is achieved by the method according to the present invention. [Brief explanation of the drawing]

[0069] [Figure 1] This is the X-ray diffraction pattern of a sample using the WNiMo sputtering target according to the present invention. [Figure 2] This is the X-ray diffraction pattern of a sample of a WNiCr sputtering target according to the present invention. [Figure 3] This is the microstructure of the WNiMo sputtering target according to the present invention (optical microscopy). [Figure 4] This is the microstructure (optical microscopy) of the WNiCr sputtering target according to the present invention. [Modes for carrying out the invention]

[0070] <Embodiment> The present invention will be described below with reference to manufacturing examples and drawings. [Examples]

[0071] Example 1 (Manufacturing of WNiMo tubes): The raw materials used were W metal powder with a particle size of 4 μm as measured by the Fischer method, Ni metal powder with a particle size of 4.2 μm as measured by the Fischer method, and Mo metal powder with a particle size of 4.6 μm as measured by the Fischer method. The powders were introduced into a sealed container in the ratios of 42 wt% W, 47 wt% Ni, and 11 wt% Mo, and mixed in a shaker for 1 hour.

[0072] A 141 mm diameter steel mandrel was placed in the center of a 300 mm diameter rubber tab, with one end closed. The powder mixture was introduced into the intermediate space between the steel core and the rubber wall, and the rubber tube was closed at its open end with a rubber cap. The closed rubber tube was placed in a cold isostatic press and pressed at a pressure of 200 MPa to obtain an unsintered body in the form of a disc with a relative density of approximately 59% and an outer diameter of 242 mm.

[0073] The unsintered bodies produced in this manner were sintered in an indirect sintering furnace in a hydrogen atmosphere at a temperature of approximately 1250°C. The relative density after sintering was approximately 80%.

[0074] The hardness of the target material was 126 HV10. The oxygen content was measured at 190 μg / g.

[0075] Figure 1 shows the X-ray diffraction pattern of this embodiment. JCPDS cards 00-004-806 (W) (corresponding to the W phase), 01-071-9764 (Mo 1.08 Ni 2.92), and 01-072-2652 (Ni 0.85 W 0.15) (corresponding to the mixed phase) were used to evaluate the diffraction pattern. From this figure, it is clear that the pure Ni phase (appearing at 2θ = 44.5°) is not present in the X-ray pattern. The peak at 2θ = 40.2° indicates the pure W phase.

[0076] The fine structure is shown in Figure 3 using an optical microscope image. In the optical microscope, for example, a sample such as a test tube is approximately 15 × 15 × 15 mm in size. 3After cutting, the specimen is placed in an embedding mold and filled with plastic granules. In the press, pressure and temperature are used to melt the granules, and after cooling, the test specimen is embedded in the plastic. The surface to be inspected is then polished with sandpaper ranging from coarse to fine, and finally polished with a diamond suspension. The sample is then prepared directly for inspection under an optical microscope. W particles (dark gray) are located in a mixture of NiWMo (light color). Black indicates pores produced by powder metallurgy.

[0077] Example 2 (Manufacturing of WNiCr plate): In this case as well, the raw materials used were W metal powder with a particle size of 4 μm as measured by the Fischer method, Ni metal powder with a particle size of 4.2 μm as measured by the Fischer method, and Cr metal powder (sieved to less than 45 μm). The powders were introduced into a sealed container in the ratios of 67 wt% W, 26 wt% Ni, and 7 wt% Cr, and mixed in a shaker for 1 hour.

[0078] The powder mixture was introduced into a flexible rubber tube, whose open end was closed with a rubber cap. The closed rubber tube was placed in a cold isostatic press and pressed at a pressure of 200 MPa to obtain an unsintered body in the form of a plate with a relative density of approximately 64.9%.

[0079] The green material produced in this manner was sintered at approximately 1400°C for 4 hours in a hydrogen atmosphere in an indirect sintering furnace. The relative density after sintering was approximately 90%. The approximate dimensions of the plate were 268 × 48.7 × 343 mm. 3 The target material had a hardness of 189 HV10 and an oxygen content of 50 μg / g.

[0080] Figure 2 shows the X-ray diffraction pattern of this embodiment. JCPDS card 00-004-806(W), 03-065-5108(Cr4Ni 15The following materials were used: W), 01-071-7594 (CrNi), 03-065-6291 Cr2Ni3, and 01-077-3140 (Ni9W) 0.4. From this figure, it is clear that the pure Ni phase (appearing at 2θ = 44.5°) is not present in the X-ray pattern. The peak at 2θ = 40.2° indicates the pure W phase.

[0081] The microstructure is shown in Figure 4 using an optical microscope image. A sample of this plate is prepared as described in Example 1.

[0082] W particles (dark gray) are located within a mixture of NiWCr (light color). Black indicates pores produced by powder metallurgy.

Claims

1. A sputtering target manufactured by powder metallurgy, The sputtering target comprises tungsten (W), nickel (Ni), and one other metal X selected from the group consisting of group 5 or group 6 of the periodic table, as well as unavoidable impurities. The sputtering target has a two-phase microstructure, one phase being pure W, and the other phase being a mixed phase selected from the group consisting of NiWX, NiW, NiX, and mixtures thereof. Sputtering target.

2. The other metal X is a type of metal selected from the elements Cr, Mo, Nb, or Ta. The sputtering target according to claim 1.

3. The sputtering target is characterized by 38-70% by weight of W, 25-50% by weight of Ni, 5-22% by weight of X, and a maximum proportion of unavoidable impurities of 650 μg / g or less. The total amount of W + Ni + X + impurities is 100% by weight. A sputtering target according to claim 1 or 2.

4. The density of the sputtering target is at least 85%. A sputtering target according to any one of claims 1 to 3.

5. The oxygen content is less than 350 μg / g. A sputtering target according to any one of claims 1 to 4.

6. The oxygen content is less than 100 μg / g. The sputtering target according to claim 5.

7. A tubular sputtering target, A sputtering target according to any one of claims 1 to 6.

8. Planar sputtering target, A sputtering target according to any one of claims 1 to 6.

9. The area ratio of the W phase measured in the cross-section of the target material is between 5% and 50%. A sputtering target according to any one of claims 1 to 8.

10. The average particle size of the W phase is less than 40 μm. A sputtering target according to any one of claims 1 to 9.

11. A method for manufacturing a WNiX sputtering target via a powder metallurgy pathway, At least the following: A blank is obtained by a compaction process in which a mixed powder of W powder, Ni powder, and X powder is compressed under pressure, heated, or compressed under pressure and heated. A method characterized by including the step of

12. The aforementioned compaction process is carried out by sintering at a temperature of 1100 to 1450°C. A method for manufacturing a WNiX sputtering target according to claim 11.

13. Following the aforementioned compaction step, a molding step is included. A method for manufacturing a WNiX sputtering target according to claim 11 or 12.

14. Forming is carried out by rolling or forging. The method according to claim 13.

15. After the molding process, heat treatment is performed. The method according to claim 13 or 14.

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