Sputtering target and method for manufacturing the same

Abstract

The purpose of the present invention is to provide: a sputtering target that makes it possible to perform film formation in which contamination by particles is suppressed on the occasion of sputtering; and a method for producing the sputtering target. A sputtering target according to the present invention is an alloy sputtering target formed from ruthenium serving as a first element and at least one substance serving as a second element and selected from among boron, aluminum, titanium, zirconium, hafnium, vanadium, niobium, tantalum, chrome, molybdenum, and tungsten. The sputtering target is produced by a method including a preparation step for preparing raw materials, an atomization step in which an alloy powder is obtained by atomization, a mixing step in which a ruthenium raw material is additionally added to the alloy powder and a mixture is obtained, and a sintering step (a fourth step) in which the mixture is sintered and a sintered body is obtained. The maximum major diameter of the alloy powder obtained by atomization is 500 μm or less.

Description

[Technical Field]

[0001] This disclosure relates to a sputtering target suitable for forming a protective film on a mask blank, which is the original plate for a mask used when performing EUV lithography using extreme ultraviolet (EUV) light, or a pellicle film to prevent foreign matter from adhering to the mask pattern surface. [Background technology]

[0002] In semiconductor devices, miniaturization of electronic circuits that make up IC chips is required, and fine circuit patterns are formed using technologies such as EUV lithography. However, even minute defects such as dust or scratches of a few nanometers during manufacturing can become fatal defects in operation, so the material of the thin film used for the mask blanks, which serve as the original plates for the masks, is also important.

[0003] For thin films called blanks or pellicles used in EUV applications, alloy materials with ruthenium added are used due to their advantages in EUV light transmission or absorption, as well as thermal conductivity. These thin films are formed using the sputtering method.

[0004] A sputtering target has been disclosed for use in manufacturing reflective mask blanks for EUV lithography, comprising a ruthenium compound containing ruthenium and at least one selected from niobium, molybdenum, zirconium, titanium, lanthanum, silicon, boron, and yttrium (see, for example, Patent Document 1). Patent Document 1 states that for niobium, molybdenum, zirconium, titanium, lanthanum, and silicon, the content in the compound is preferably in the range of 3 to 75 atomic percent, and particularly from the viewpoint of improving chemical resistance, it is desirable that it be in the range of 40 to 75 atomic percent. Furthermore, Patent Document 1 states that for boron and yttrium, since they are metals that are easily oxidized, if the content of these metals is high, an oxide layer may be formed on the surface of the deposited ruthenium compound film, which may degrade the optical properties (e.g., reflectivity of EUV light), so the content in the compound is preferably in the range of 3 to 50 atomic percent. Furthermore, Patent Document 1 states that among the impurities, the oxygen content is particularly low at 2000 ppm or less, and the carbon content is low at 200 ppm or less, and that the low content of both oxygen and carbon reduces the amount of particles generated from the target during film formation.

[0005] [Patent Document 1] Japanese Patent Publication No. 2006-283054 [Overview of the Initiative] [Problems that the invention aims to solve]

[0006] However, if particles that cause defects in the film are generated during film deposition, they adhere to the film, causing defects and reducing the film yield. In the case of blanks, patterning is applied on top of them to create the design blueprint for the semiconductor, so particle adhesion to the film is an extremely important issue. In the case of pellicles, the areas where particles adhere have reduced EUV light transmission ability, affecting circuit transfer and causing a decrease in yield. There are many factors that cause particles to be generated during film deposition, but target-related particles include arcing from voids due to density defects or arcing from oxides on the target surface.

[0007] Furthermore, in the case of blanks or pellicles, the thickness of the deposited film is extremely thin, and the area over which the film is deposited is relatively wide, making in-plane uniformity of film thickness and composition crucial. Therefore, until now, sputtering targets have required increased target density and reduced oxygen content. However, with the formation of finer circuit patterns, the particles causing defects have become even smaller, and it has become suspected that not only the aforementioned particle sources, but also the materials added to ruthenium themselves are being scattered during film deposition.

[0008] Ruthenium alloy targets have been manufactured by melting methods to reduce oxygen content and improve density. However, ruthenium and the added elements generally have high melting points exceeding 1600°C, making melting difficult. Furthermore, because ruthenium and the added elements form various intermetallic compounds (IMCs), cracks are prone to occur during the solidification process, and cracks occur when processing is performed after melting and solidification, making it difficult to shape the target material. Even if the target material can be shaped, IMCs precipitate and coarse during the solidification process, worsening the compositional distribution in the target plane and cross-sectional direction (also called the target thickness direction). As a result, the sputtering rate during sputtering varies depending on the location within the target, and the uniformity of the in-plane compositional distribution and film thickness distribution of the deposited film deteriorates. Hot working of target materials is common to refine the microstructure, but this is not possible because IMCs precipitate and coarse, causing cracks or fractures.

[0009] Another method for highly dispersing additive elements within the target is sintering. The finer the powder used, the easier it is to disperse the additive elements within the target. However, handling fine powders of highly reactive additive elements can cause fires, making them difficult. Furthermore, even with stable additive elements, finer powders have a larger specific surface area, leading to increased oxidation and a higher oxygen content in the target. Therefore, it becomes necessary to use powders with relatively coarse particle sizes, but achieving high dispersion of these requires high-energy mixing processes. However, suppressing oxidation of additive elements requires extensive atmosphere control and can lead to contamination from impurities in the mixing medium, making it unsuitable for EUV sputtering targets where high purity is required.

[0010] Therefore, the purpose of this disclosure is to provide a sputtering target and a method for manufacturing the same that enable film formation while suppressing the inclusion of particles during sputtering. [Means for solving the problem]

[0011] The inventors of the present invention diligently studied to solve the above problems and concluded that the cause of particle contamination is likely oxidation and carbonization of the additive elements within the target, or that the additive elements of the target exist as single metals without being alloyed. They hypothesized that particles are mixed into the film when a film is formed using the aforementioned target, and thus discovered a sputtering target and a method for manufacturing the same to suppress this, completing the present invention. That is, the sputtering target according to the present invention Manufacturing method It consists of ruthenium as the first element and boron as the second element. 、 Titanium, zirconium, hafnium, vanadium, niobium, tantalum 、 A method for manufacturing a sputtering target of an alloy composed of one selected from molybdenum and tungsten, comprising a preparation step of preparing raw materials in which the first element and the second element are in a predetermined elemental ratio, and 1 × 10 -2The method comprises an atomization step of obtaining alloy powder by atomization using the raw materials in a vacuum atmosphere of Pa or less, a nitrogen gas atmosphere containing 0 to 4 vol% or less of hydrogen gas, or an inert gas atmosphere containing 0 to 4 vol% or less of hydrogen gas; a mixing step of further adding ruthenium raw material to the alloy powder to obtain a mixture; and a sintering step of obtaining a sintered body by sintering the mixture using a hot press (HP), discharge plasma sintering (SPS), or hot isostatic sintering (HIP) in a vacuum atmosphere of 50 Pa or less, a nitrogen gas atmosphere containing 0 to 4 vol% or less of hydrogen gas, or an inert gas atmosphere containing 0 to 4 vol% or less of hydrogen gas, wherein the maximum major diameter of the alloy powder obtained by the atomization method is 500 μm or less. Because the oxidation and carbonization of the added element (second element) can be suppressed while it is dispersed in the sputtering target, the composition of the film formed using the target can be made uniform in both the in-plane direction and the film thickness direction while suppressing the inclusion of particles. By limiting the maximum major diameter of the alloy powder to 500 μm or less, a highly packed sputtering target can be formed in the process of obtaining the sintered body. As a result, a uniform compositional distribution can be obtained for the film deposited using the target, both in the in-plane direction and in the film thickness direction. Furthermore, by adding ruthenium raw material, pure metal powder can be placed between the hard alloy powders in the process of obtaining the sintered body, thereby forming a sputtering target with higher density. As a result, a uniform compositional distribution can be obtained for the film deposited using the target, both in the in-plane direction and in the film thickness direction. In addition, by suppressing arcing from voids due to poor density, the generation of particles can be suppressed.

[0012] The sputtering target manufacturing method according to the present invention preferably further includes a classification step between the atomization step and the mixing step, in which particles with a maximum major diameter exceeding 500 μm are removed from the alloy powder obtained by the atomization method. In the step of obtaining the sintered body, a sputtering target with high density can be formed, and a uniform compositional distribution can be obtained for the film formed using the target, both in the in-plane direction and in the film thickness direction.

[0013] In the sputtering target manufacturing method according to the present invention, the packing rate of the sputtering target is preferably 80% or more. By increasing the packing rate, a sputtering target with fewer voids can be made, which suppresses the inclusion of particles when a film is formed using the sputtering target, and because the sputtering rate does not vary much from place to place, a thin film with less deviation in thickness and composition can be formed.

[0014] In the sputtering target manufacturing method according to the present invention, the ruthenium raw material is 1 × 10 -2 It is preferable that the ruthenium powder is obtained by atomization in a vacuum atmosphere of Pa or less, a nitrogen gas atmosphere containing 0 to 4 vol% or less of hydrogen gas, or an inert gas atmosphere containing 0 to 4 vol% or less of hydrogen gas. Since the ruthenium element can be dispersed in the sputtering target while suppressing oxidation and carbonization, the composition of the film formed using the target can be made uniform in both the in-plane direction and the film thickness direction while suppressing particle contamination.

[0015] In the sputtering target according to the present invention, the content of the second element is preferably 3 to 70 atomic percent. The composition of the deposited film improves corrosion resistance and ensures reflectivity that meets the requirements for EUV.

[0016] The sputtering target according to the present invention is a sputtering target of an alloy composed of ruthenium as a first element and one selected from boron, aluminum, titanium, zirconium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, and tungsten as a second element, wherein the sputtering target has dispersed particles composed of two phases, including an intermetallic compound phase consisting of the first and second elements, in a ruthenium matrix, and the maximum major diameter of the dispersed particles is 500 μm or less.

[0017] In the sputtering target according to the present invention, the two phases include forms in which (1) the intermetallic compound phase and the metallic phase of the first element, which is a metallic ruthenium phase, (2) a combination of two types of the intermetallic compound phases, or (3) a combination of the intermetallic compound phase and the metallic phase of the second element.

[0018] The sputtering target according to the present invention contains ruthenium as the first element and boron as the second element. 、 zirconium 、 Vanadium, Niobium 、 A sputtering target made of an alloy composed of one selected from chromium, molybdenum, and tungsten, wherein the sputtering target has dispersed particles in a ruthenium matrix, which are composed of an intermetallic compound phase consisting of two elements, the first element and the second element, and the maximum major diameter of the dispersed particles is 500 μm or less.

[0019] In the sputtering target according to the present invention, in (Condition 1) or (Condition 2), the relative integrated intensity of the first peak of the single metal with a lower content in the alloy among the first element or the second element by X-ray diffraction in the in-plane direction of the sputtering surface of the sputtering target is preferably at least one location where it is 12% or less with respect to the relative integrated intensity of the measured main peak. A sputtering target with reduced compositional deviation due to location can be obtained. When forming a film using the target, by suppressing the deviation in sputtering rate between the alloy portion and the single metal portion and suppressing abnormal discharge occurring between the alloy and the single metal, a film with reduced particles due to the single metal can be obtained. (Condition 1) In-plane direction of the sputtering surface: The sputtering target is a disc-shaped target with a center O and a radius r, and the measurement locations are on a virtual crosshair that intersects at the center O and is orthogonal, including a total of 9 locations: one location at the center O, four locations 0.45r away from the center O, and four locations 0.9r away from the center O. (Condition 2) In-plane direction of the sputtering surface: The sputtering target is a rectangle with a vertical length of L1 and a horizontal length of L2 (including a square where L1 and L2 are equal. Or, the rectangle includes a rectangle obtained by unfolding the side surface of a cylindrical shape with a length J and a circumference K. In this form, L2 corresponds to the length J, L1 corresponds to the circumference K, and the relationship between the length J and the circumference K is J>K, J=K, or J<K). And the measurement locations are on a virtual crosshair that intersects at the center of gravity O and is orthogonal. When the virtual crosshair is orthogonal to the sides of the rectangle, there are a total of 9 locations: one location at the center of gravity O, two locations on the virtual crosshair and 0.25L1 away from the center of gravity O in the vertical direction, two locations on the virtual crosshair and 0.25L2 away from the center of gravity O in the horizontal direction, two locations on the virtual crosshair and 0.45L1 away from the center of gravity O in the vertical direction, and two locations on the virtual crosshair and 0.45L2 away from the center of gravity O in the horizontal direction.

[0020] In the sputtering target according to the present invention, in (Condition 1) or (Condition 2), the relative integrated intensity of the first peak of the single metal with the lower content in the alloy among the first element or the second element by X-ray diffraction in the sputtering surface direction of the sputtering target is preferably 12% or less with respect to the relative integrated intensity of the main peak to be measured. By having many regions where the compositional deviation due to the location is suppressed, the deviation in the sputtering rate between the alloy portion and the single metal portion is suppressed, and abnormal discharge generated between the alloy and the single metal is suppressed, so that a film with reduced particles due to the single metal can be obtained.

[0021] In the sputtering target according to the present invention, the oxygen content is preferably 500 ppm or less. By suppressing the formation of the oxide of the second element in the sputtering target by the bonding of oxygen with the second element, abnormal discharge due to the oxide of the second element is suppressed, and thus the generation of particles can be suppressed.

[0022] In the sputtering target according to the present invention, the carbon content is preferably 200 ppm or less. By suppressing the formation of the carbide of the second element in the sputtering target by the bonding of carbon with the second element, abnormal discharge due to the carbide of the second element is suppressed, and thus the generation of particles can be suppressed.

Effect of the Invention

[0023] The present disclosure can provide a sputtering target capable of forming a film with suppressed contamination of particles during sputtering and a method for manufacturing the same.

Brief Description of the Drawings

[0024] [Figure 1] It is a schematic view showing measurement locations in the sputtering surface direction of a disk-shaped target. [Figure 2] It is a schematic view showing measurement locations in the target thickness direction of a disk-shaped target shown by a B-B cross section. [Figure 3] This is a schematic diagram showing the measurement points in the sputtering plane direction of a square plate-shaped target. [Figure 4] This is a schematic diagram showing the measurement points in the target thickness direction of a square plate-shaped target represented by a C-C cross section. [Figure 5] This is a conceptual diagram illustrating the measurement points on a cylindrical target. [Figure 6] This is an explanatory diagram to explain the concept of maternal features. [Modes for carrying out the invention]

[0025] The present invention will be described in detail below with reference to embodiments, but the present invention is not limited to these descriptions. Various modifications of the embodiments are possible as long as they achieve the effects of the present invention.

[0026] The sputtering target according to this embodiment is an alloy sputtering target composed of ruthenium as the first element and one selected from boron, aluminum, titanium, zirconium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, and tungsten as the second element, and the method for manufacturing the sputtering target comprises a preparation step (first step) of preparing raw materials in which the first element and the second element are in a predetermined elemental ratio, and 1 × 10 -2 The process comprises: an atomization step (second step) to obtain alloy powder by atomization using the raw materials in a vacuum atmosphere of Pa or less, a nitrogen gas atmosphere containing 0 to 4 vol% or less of hydrogen gas, or an inert gas atmosphere containing 0 to 4 vol% or less of hydrogen gas; a mixing step (third step) to obtain a mixture by further adding ruthenium raw material to the alloy powder; and a sintering step (fourth step) to obtain a sintered body by sintering the mixture using the hot press method (HP), discharge plasma sintering method (SPS), or hot isostatic sintering method (HIP) in a vacuum atmosphere of 50 Pa or less, a nitrogen gas atmosphere containing 0 to 4 vol% or less of hydrogen gas, or an inert gas atmosphere containing 0 to 4 vol% or less of hydrogen gas, wherein the maximum major diameter of the alloy powder obtained by atomization is 500 μm or less.

[0027] [Project 1 (Preparation Work)] This process is for producing the raw materials (hereinafter simply referred to as "raw materials") used in the second process to produce alloy powders of the first and second elements. The raw materials are raw materials for ruthenium-boron alloys, ruthenium-aluminum alloys, ruthenium-titanium alloys, ruthenium-zirconium alloys, ruthenium-hafnium alloys, ruthenium-vanadium alloys, ruthenium-niobium alloys, ruthenium-tantalum alloys, ruthenium-chromium alloys, ruthenium-molybdenum alloys, or ruthenium-tungsten alloys. Examples of raw materials for producing powder in the first step include (1A) preparing individual metals of the constituent elements of the alloy target as starting materials and mixing them to produce the raw material, (2A) preparing an alloy with the same composition as the alloy target as a starting material and using it as the raw material, or (3A) preparing an alloy with the same or partially missing constituent elements as the alloy target, with a composition ratio that deviates from the desired composition ratio, along with individual metals to be added to adjust to the desired composition, and mixing them to produce the raw material. As starting materials, one of the following is introduced into a melting apparatus and melted to produce the raw material: ruthenium and boron, ruthenium and aluminum, ruthenium and titanium, ruthenium and zirconium, ruthenium and hafnium, ruthenium and vanadium, ruthenium and niobium, ruthenium and tantalum, ruthenium and chromium, ruthenium and molybdenum, or ruthenium and tungsten. After melting, it is preferable to use materials with few impurities in the melting apparatus and containers so as not to introduce a large amount of impurities into the raw material. For the dissolution method, select a method that can handle the following dissolution temperatures.In terms of melting temperature, it is used as a raw material for ruthenium-boron alloys at 1400-2400°C, for ruthenium-aluminum alloys at 1600-2400°C, for ruthenium-titanium alloys at 1700-2400°C, for ruthenium-zirconium alloys at 1700-2400°C, for ruthenium-hafnium alloys at 2000-2500°C, and for ruthenium at 1700-2400°C. The raw materials for nium-vanadium alloys are heated at 1600-2400°C, ruthenium-niobium alloys at 1900-2800°C, ruthenium-tantalum alloys at 1600-2400°C, ruthenium-chromium alloys at 1900-2400°C, ruthenium-molybdenum alloys at 1900-2400°C, or ruthenium-tungsten alloys at 2200-2900°C. The atmosphere inside the melting apparatus is a vacuum of 1 × 10⁻⁶. ‐2 The atmosphere may be a vacuum below Pa, a nitrogen gas atmosphere containing 0-4 vol% or less of hydrogen gas, or an inert gas atmosphere containing 0-4 vol% or less of hydrogen gas.

[0028] The raw material for the alloy powder may be in the form of alloy grains or alloy lumps, or a combination of powder, grains, and lumps, in addition to the three raw material forms described in (1A), (2A), and (3A) above. Powder, grains, and lumps refer to differences in particle size, but there are no particular restrictions on particle size as long as it can be used in the powder manufacturing apparatus in the second step. Specifically, since the raw material is dissolved in the powder manufacturing apparatus in the second step, there are no particular restrictions as long as the raw material is of a size that can be supplied to the powder manufacturing apparatus.

[0029] [Second Process (Atomization Process)] This process is for producing alloy powders of a first element and a second element. The alloy powders of a first element and a second element are ruthenium-boron alloy powder, ruthenium-aluminum alloy powder, ruthenium-titanium alloy powder, ruthenium-zirconium alloy powder, ruthenium-hafnium alloy powder, ruthenium-vanadium alloy powder, ruthenium-niobium alloy powder, ruthenium-tantalum alloy powder, ruthenium-chromium alloy powder, ruthenium-molybdenum alloy powder, or ruthenium-tungsten alloy powder. The raw materials produced in the first step are put into a powder manufacturing apparatus, melted to form molten metal, and then gas is blown onto the molten metal to scatter it and rapidly cool and solidify to produce powder. To prevent a large amount of impurities from being mixed into the alloy powder of the first and second elements after melting, it is preferable to use materials with low impurity content for the apparatus and containers used in the powder manufacturing apparatus. As for the melting method, a method that can handle the following melting temperatures should be selected. In terms of melting temperature, it is used as a raw material for ruthenium-boron alloys at 1400-2400°C, for ruthenium-aluminum alloys at 1600-2400°C, for ruthenium-titanium alloys at 1700-2400°C, for ruthenium-zirconium alloys at 1700-2400°C, for ruthenium-hafnium alloys at 2000-2500°C, and for ruthenium at 1700-2400°C. The raw materials for nium-vanadium alloys are heated at 1600-2400°C, ruthenium-niobium alloys at 1900-2800°C, ruthenium-tantalum alloys at 1600-2400°C, ruthenium-chromium alloys at 1600-2400°C, ruthenium-molybdenum alloys at 1900-2400°C, or ruthenium-tungsten alloys at 2200-2900°C. The atmosphere inside the powder manufacturing apparatus is a vacuum of 1 × 10⁻⁶. ‐2The process is carried out in a vacuum atmosphere of Pa or less, a nitrogen gas atmosphere containing 0 to 4 vol% or less of hydrogen gas, or an inert gas atmosphere containing 0 to 4 vol% or less of hydrogen gas. The temperature of the molten metal when spraying is preferably "100°C or higher above the melting point of the first and second elements, depending on the type of alloy of the first and second elements," and more preferably "150 to 250°C above the melting point of the first and second elements, depending on the type of alloy of the first and second elements." If the temperature is too high, cooling during granulation will not be sufficient, making it difficult to form a powder and potentially reducing production efficiency. Conversely, if the temperature is too low, problems such as nozzle clogging during spraying are likely to occur. The gas used when spraying is nitrogen or argon, etc., but is not limited to these. In the case of alloy powder, the size of precipitated particles corresponding to islands in a sea-island structure may be small. This state is already achieved at the alloy powder stage and is maintained even after sintering or when a target is formed. Therefore, the generation of a phase containing many additives that occurs when a sputtering target is made by the melting method can be suppressed by producing the alloy powder through this process. When a sputtering target is made using the alloy powder produced through this process and a film is formed, the difference in sputtering rate between different areas can be suppressed. The rapidly cooled powder has the elemental ratio of the first element to the second element in the raw materials prepared in the first step. At this time, the maximum major diameter of the powder obtained by the atomization method is 500 μm or less, preferably 400 μm or less, and more preferably 300 μm or less. If the maximum major diameter of the powder is greater than 500 μm, the density will be insufficient even after sintering in the fourth step, and when a thin film is formed using the target, particles will be mixed in, causing variations in film thickness. Therefore, it is necessary to make the particle size of the powder 500 μm or less. Here, "maximum major axis of 500 μm or less" means that the product does not contain any particles with a major axis exceeding 500 μm.

[0030] In this embodiment, the method for manufacturing a sputtering target preferably further includes a classification step between the atomization step and the mixing step, in which particles with a maximum major diameter exceeding 500 μm are removed from the alloy powder obtained by the atomization method. By classifying and adjusting the particle size, a sputtering target with higher density can be formed in the step of obtaining the sintered body, and a uniform compositional distribution can be obtained for the film formed using the target, both in the in-plane direction and in the film thickness direction.

[0031] [3rd process (mixing process)] This step involves incorporating ruthenium into the target in addition to the alloy of the first and second elements, and is a step in producing a mixture of the alloy powder obtained in the second step and the ruthenium raw material. The mixture of alloy powder and ruthenium is a mixture of ruthenium and a ruthenium-boron alloy, a mixture of ruthenium and a ruthenium-aluminum alloy, a mixture of ruthenium and a ruthenium-titanium alloy, a mixture of ruthenium and a ruthenium-zirconium alloy, a mixture of ruthenium and a ruthenium-hafnium alloy, a mixture of ruthenium and a ruthenium-vanadium alloy, a mixture of ruthenium and a ruthenium-niobium alloy, a mixture of ruthenium and a ruthenium-tantalum alloy, a mixture of ruthenium and a ruthenium-chromium alloy, a mixture of ruthenium and a ruthenium-molybdenum alloy, or a mixture of ruthenium and a ruthenium-tungsten alloy. The maximum major axis of the ruthenium raw material added in the third step is preferably 500 μm or less, more preferably 400 μm or less, and even more preferably 300 μm or less.

[0032] In the sputtering target manufacturing method according to this embodiment, the ruthenium raw material is 1 × 10 -2The ruthenium powder may be obtained by atomization in a vacuum atmosphere of Pa or less, a nitrogen gas atmosphere containing 0-4 vol% or less of hydrogen gas, or an inert gas atmosphere containing 0-4 vol% or less of hydrogen gas. When the ruthenium raw material is ruthenium powder obtained by atomization, the ruthenium raw material supplied to the powder manufacturing apparatus may be powder, granules, lumps, or a combination thereof. Powder, granules, and lumps describe differences in particle size, but there are no particular restrictions on particle size as long as it can be used in a powder manufacturing apparatus using the atomization method. Specifically, since the raw material is dissolved in the powder manufacturing apparatus using the atomization method, there are no particular restrictions as long as the size of the raw material can be supplied to the powder manufacturing apparatus. Furthermore, if ruthenium powder with a purity of 3N or higher is prepared separately as the ruthenium raw material to be added in the third step, an atomization step to prepare the ruthenium raw material is not necessarily required.

[0033] [Fourth Process (Sintering Process)] This step is to obtain a target sintered body from the mixture obtained in the third step. Sintering is performed by hot pressing (HP), plasma discharge sintering (SPS), or hot isostatic pressing (HIP). Sintering is performed using an alloy powder of the first and second elements obtained in the third step, or a mixture of the alloy powder classified in the classification step and a ruthenium raw material. Preferably, one of the powders described above is packed into a mold, and the powder is sealed in the mold and punched with a pre-pressurized pressure of 10 to 30 MPa before sintering. At this time, the sintering temperature is preferably 1100 to 2000°C, and the applied pressure is preferably 40 to 196 MPa. The sintering temperature is 1150-1300°C for ruthenium and ruthenium-boron alloy mixtures, 1150-1500°C for ruthenium and ruthenium-aluminum alloy mixtures, 1150-1600°C for ruthenium and ruthenium-titanium alloy mixtures, 1150-1300°C for ruthenium and ruthenium-zirconium alloy mixtures, 1250-1400°C for ruthenium and ruthenium-hafnium alloy mixtures, and for ruthenium and ruthenium-vanadium alloy mixtures. For mixtures, 1250-1400°C is preferable; for mixtures of ruthenium and ruthenium-niobium alloys, 1150-1400°C; for mixtures of ruthenium and ruthenium-tantalum alloys, 1400-1800°C; for mixtures of ruthenium and ruthenium-chromium alloys, 1100-1250°C; for mixtures of ruthenium and ruthenium-molybdenum alloys, 1400-1800°C; or for mixtures of ruthenium and ruthenium-tungsten alloys, 1500-2000°C is more preferable. The atmosphere inside the sintering apparatus is a vacuum atmosphere with a vacuum level of 50 Pa or less, a nitrogen gas atmosphere containing 4 vol% or less of hydrogen gas, or an inert gas atmosphere containing 4 vol% or less of hydrogen gas. It is preferable that the hydrogen gas content is 0.1 vol% or more.

[0034] By going through at least the first to fourth steps, it is possible to manufacture a sputtering target that suppresses compositional deviations in the in-plane direction and the thickness direction of the target, and that prevents variations in sputtering rate from being seen in different locations and prevents particles from being mixed into the film due to abnormal discharges.

[0035] The packing density of the sputtering target according to this embodiment is preferably 80% or more, more preferably 95% or more, and even more preferably 98% or more. By increasing the packing density, a sputtering target with fewer voids can be made, which suppresses the inclusion of particles when a film is formed using the sputtering target, and because the sputtering rate does not vary much from place to place, a thin film with less variation in thickness and composition can be formed. In this embodiment, a sputtering target with such a high packing density can be made by setting the maximum major diameter of the dispersed particles to 500 μm or less.

[0036] In this embodiment, the sputtering target preferably has a second element content of 3 to 70 atomic percent, more preferably 5 to 65 atomic percent, and even more preferably 10 to 60 atomic percent. If the content is less than 3 atomic percent, improvement in the reflectivity of the film cannot be expected when a thin film is formed using the target, and if the content is more than 70 atomic percent, the chemical resistance will decrease due to the low amount of ruthenium, making it difficult to use the film even if it is formed using the target. Therefore, it is preferable to have a content of 3 to 70 atomic percent.

[0037] The boron content is preferably 25-65 atomic%, and more preferably 30-60 atomic%. The aluminum content is preferably 20-60 atomic%, and more preferably 30-55 atomic%. The titanium content is preferably 10-65 atomic%, and more preferably 25-50 atomic%. The zirconium content is preferably 15-65 atomic%, and more preferably 20-50 atomic%. The hafnium content is preferably 15-65 atomic%, and more preferably 20-50 atomic%. The vanadium content is preferably 35-65 atomic%, and more preferably 40-60 atomic%. The niobium content is preferably 15-60 atomic%, and more preferably 20-50 atomic%. The tantalum content is preferably 10-65 atomic%, and more preferably 25-40 atomic%. The chromium content is preferably 30 to 65 atomic%, and more preferably 40 to 60 atomic%. The molybdenum content is preferably 25 to 65 atomic%, and more preferably 30 to 60 atomic%. The tungsten content is preferably 10 to 65 atomic%, and more preferably 15 to 60 atomic%.

[0038] The sputtering target according to this embodiment includes two forms: one in which dispersed particles are composed of two phases, including an intermetallic compound phase consisting of two elements, a first element and a second element, in a ruthenium matrix (first embodiment); and another in which dispersed particles are composed of one phase, the intermetallic compound phase consisting of the first and second elements, in a ruthenium matrix (second embodiment). Hereafter, when simply referred to as "this embodiment," it means encompassing both the first and second embodiments.

[0039] [First Embodiment] The sputtering target according to the first embodiment is an alloy sputtering target composed of ruthenium as the first element and one selected from boron, aluminum, titanium, zirconium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, and tungsten as the second element (hereinafter sometimes referred to as the additive element or AE). The sputtering target has dispersed particles composed of two phases, including an intermetallic compound phase consisting of the first and second elements, in a ruthenium matrix, with the maximum major axis of the dispersed particles being 500 μm or less. The dispersed particles present in the sputtering target correspond to the constituent particles of the sintered body, for example, when the sputtering target is a sintered body. The dispersed particles are dispersed in the ruthenium matrix. The dispersed particles have multiple crystal grains.

[0040] In the sputtering target according to the first embodiment, the two phases include (1) a combination of an intermetallic compound phase and a metallic ruthenium phase which is the metallic phase of the first element, (2) a combination of two types of intermetallic compound phases, or (3) a combination of an intermetallic compound phase and a metallic phase which is the metallic phase of the second element. In this embodiment, the number of phases is determined by the phases identified by X-ray diffraction. Furthermore, intermetallic compounds formed at grain boundaries are not included as part of the two phases. The dispersed particles have two types of crystal grains corresponding to the two phases.

[0041] A grain boundary encompasses the boundary between a dispersed particle and an adjacent dispersed particle, or the boundary between a crystal grain and an adjacent crystal grain.

[0042] Using the example of three types of intermetallic compounds, Ru2AE, and RuAE2, we will explain the following: "(1) The two phases are a combination of an intermetallic compound phase and a metallic ruthenium phase which is the metallic phase of the first element," "(2) The two phases are a combination of two types of intermetallic compound phases," and "(3) The two phases are a combination of an intermetallic compound phase and a metallic phase which is the metallic phase of the second element." In this case, the forms of the phases that appear include a form with only the metallic ruthenium phase (however, including a solid solution in which the second element is dissolved in ruthenium), a form with the Ru phase (however, including a solid solution in which the second element is dissolved in ruthenium) and any one of the Ru2AE phase, RuAE phase, or RuAE2 phase, a form with only the Ru2AE phase, a form with the Ru2AE phase and the RuAE phase, a form with the Ru2AE phase and the RuAE2 phase, a form with only the RuAE phase, a form with the RuAE phase and the RuAE2 phase, a form with only the RuAE2 phase, any one of the RuAE2 phase, RuAE phase, or Ru2AE phase and the AE phase (however, including a solid solution in which ruthenium is dissolved in the second element), and a form with only the metallic phase of the second element (however, including a solid solution in which ruthenium is dissolved in the second element). Of these, "(1) a combination of an intermetallic compound phase and a metallic ruthenium phase which is the metallic phase of the first element" refers to the form of Ru phase and one of Ru2AE phase, RuAE phase, or RuAE2 phase. Also, "(2) a combination of two types of intermetallic compound phases" refers to the form of Ru2AE phase and RuAE phase, Ru2AE phase and RuAE2 phase, or RuAE phase and RuAE2 phase. Furthermore, "(3) a combination of an intermetallic compound phase and a metallic phase of the second element" refers to the form of one of RuAE2 phase, RuAE phase, or Ru2AE phase and AE phase. Cases where there are two or more types of intermetallic compounds can be classified according to the same reasoning.

[0043] Two phases appear due to two types of crystal grains with different compositions in the dispersed particles. Let's take the case where there are three types of intermetallic compounds: Ru2AE, RuAE, and RuAE2, as an example. When "the two phases are (1) a combination of an intermetallic compound phase and a metallic ruthenium phase which is the metallic phase of the first element," crystal grains of the Ru phase and crystal grains of one of the Ru2AE, RuAE, or RuAE2 phases are present in the dispersed particles. Also, when "the two phases are (2) a combination of two types of intermetallic compound phases," it means that crystal grains of the Ru2AE phase and crystal grains of the RuAE phase are present in the dispersed particles, or that crystal grains of the RuAE phase and crystal grains of the RuAE2 phase are present in the dispersed particles. Furthermore, the statement that "the two phases are a combination of (3) an intermetallic compound phase and a metallic phase of the second element" means that crystal grains of one of the RuAE2 phase, RuAE phase, or Ru2AE phase and crystal grains of the AE phase exist within the dispersed particles. The same reasoning can be applied to cases where there are two or more types of intermetallic compounds.

[0044] [Second Embodiment] The sputtering target according to the second embodiment is an alloy sputtering target composed of ruthenium as the first element and one selected from boron, aluminum, titanium, zirconium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, and tungsten as the second element, wherein the sputtering target has dispersed particles composed of an intermetallic compound phase consisting of the first and second elements in a ruthenium matrix, and the maximum major diameter of the dispersed particles is 500 μm or less. The sputtering target according to the second embodiment is the same as in the first embodiment where the two phases are a combination of (1) an intermetallic compound phase and a metallic ruthenium phase which is the metallic phase of the first element, but it has the following appearance. In other words, when the crystal grains of the metallic ruthenium phase in the dispersed particles are adjacent to the crystal grains of the metallic ruthenium phase in the ruthenium matrix in which the dispersed particles are dispersed, via grain boundaries, they appear as part of the ruthenium matrix, as if only one phase of the intermetallic compound phase exists within the ruthenium matrix; that is, it appears as if only the crystal grains of the intermetallic compound phase exist within the dispersed particles.

[0045] In the first and second embodiments, the maximum major axis of the dispersed particles is 500 μm or less, preferably 250 μm or less, more preferably 200 μm or less, and even more preferably 150 μm or less. If the maximum major axis of the dispersed particles is greater than 500 μm, there will be an uneven distribution of dispersed particles in the sputtering target, resulting in compositional deviations depending on the location on the sputtering target. When a film is formed using a sputtering target with compositional deviations, compositional deviations will occur in both the in-plane direction and the film thickness direction of the film. Therefore, it is preferable to set the maximum major axis of the dispersed particles to 500 μm or less. Here, setting the maximum major axis to 500 μm or less means that no particles with a major axis exceeding 500 μm are included. The maximum major axis is determined by measuring the distance from edge to edge of the largest dispersed particle based on the image scale in SEM image analysis within a range of 1200 μm × 1500 μm.

[0046] In the sputtering target according to this embodiment, in (Condition 1) or (Condition 2), it is preferable that there is at least one location where the relative integrated intensity of the first peak of the single metal with the lower content in the alloy among the first element or the second element by X-ray diffraction in the in-plane direction of the sputtering surface of the sputtering target is 12% or less with respect to the relative integrated intensity of the main peak to be measured. The first peak is the peak with the highest height among the peaks derived from the single metal with the lower content in the alloy among the first element or the second element in the X-ray diffraction spectrum. Also, the main peak is the peak with the highest height among all the peaks that appear in the region of CuKα, 2θ = 20 to 90° in the X-ray diffraction spectrum. (Condition 1) In-plane direction of the sputtering surface: The sputtering target is a disk-shaped target with a center O and a radius r, and the measurement locations are on a virtual crosshair orthogonal to each other with the center O as the intersection point, including a total of 9 locations: one location at the center O, a total of 4 locations 0.45r away from the center O, and a total of 4 locations 0.9r away from the center O. (Condition 2) In-plane direction of the sputtering surface: The sputtering target is a rectangle with a vertical length of L1 and a horizontal length of L2 (including a square where L1 and L2 are equal. Alternatively, the rectangle includes a rectangle obtained by unfolding the side surface of a cylindrical shape with a length J and a circumference K. In this form, L2 corresponds to the length J, L1 corresponds to the circumference K, and the relationship between the length J and the circumference K is J > K, J = K, or J < K). And the measurement locations are on a virtual crosshair orthogonal to each other with the center of gravity O as the intersection point. When the virtual crosshair is orthogonal to the sides of the rectangle, there are a total of 9 locations: one location at the center of gravity O, a total of 2 locations on the virtual crosshair and 0.25L1 away from the center of gravity O in the vertical direction, a total of 2 locations on the virtual crosshair and 0.25L2 away from the center of gravity O in the horizontal direction, a total of 2 locations on the virtual crosshair and 0.45L1 away from the center of gravity O in the vertical direction, and a total of 2 locations on the virtual crosshair and 0.45L2 away from the center of gravity O in the horizontal direction.

[0047] In X-ray diffraction, under (Condition 1) or (Condition 2), it is preferable that the nine measurement ranges are each 10 mm × 10 mm. The determination that the relative integrated intensity of the first peak of the single metal with the lower content in the alloy, obtained by X-ray diffraction in the direction of the sputtering plane of the sputtering target, is 12% or less of the relative integrated intensity of the measured main peak is made by selecting the main peak and the first peak of the single metal with the lower content in the alloy based on the graph obtained by X-ray diffraction, calculating the relative integrated intensity of the main peak and the relative integrated intensity of the first peak of the single metal with the lower content in the alloy using X-ray diffraction waveform analysis software, and determining whether the relative integrated intensity of the first peak of the single metal with the lower content in the alloy is 12% or less of the relative integrated intensity of the main peak.

[0048] The relative integrated intensity of the first peak of the single metal of the first or second element (the one with the lower content in the alloy) obtained by X-ray diffraction in the sputtering plane direction of the sputtering target is preferably 12% or less, 11% or less, and more preferably 10% or less, compared to the relative integrated intensity of the measured main peak. If the relative integrated intensity of the first peak of the single metal of the first or second element (the one with the lower content in the alloy) is greater than 12% of the relative integrated intensity of the measured main peak, a large proportion of the element is contained as a single metal without being alloyed. As a result, compositional deviations may occur between the alloy and the single metal of the first or second element in the target, or oxides or carbides of the second element may be formed due to a high proportion of the single metal of the second element. Consequently, when a thin film is formed using the target, particles may be mixed into the film due to differences in sputtering rates in different locations or the occurrence of abnormal discharges. Therefore, it is preferable that the relative integrated intensity of the first peak of the single metal of the first or second element (the one with the lower content in the alloy) be 12% or less of the relative integrated intensity of the measured main peak.

[0049] In the sputtering target according to this embodiment, under (Condition 1) or (Condition 2), it is preferable that 40% or more of the locations have a relative integrated intensity of 12% or less of the first peak of the single metal (whichever of the first or second elements has a lower content in the alloy) as measured by X-ray diffraction in the sputtering plane direction of the sputtering target, and it is more preferable that 50% or more of these locations have a relative integrated intensity of 12% or less of the main peak. By having many regions where compositional deviations between locations are suppressed, deviations in the sputtering rate between alloy locations and single metal locations are suppressed, and abnormal discharges occurring between the alloy and single metal are suppressed, thereby making it possible to obtain a film with reduced particles from the single metal. In (Condition 1) or (Condition 2), "there are 40% or more locations where the relative integrated intensity of the first peak of the single metal of the first or second element, which has a lower content in the alloy, as determined by X-ray diffraction in the sputtering plane direction of the sputtering target, is 12% or less of the relative integrated intensity of the measured main peak" means that in (Condition 1) or (Condition 2), there are 9 measurement locations, and "locations where the relative integrated intensity of the first peak of the single metal of the first or second element, which has a lower content in the alloy, as determined by X-ray diffraction in the sputtering plane direction of the sputtering target, is 12% or less of the relative integrated intensity of the measured main peak" means that in (Condition 1) or (Condition 2), where there are 9 measurement locations, "locations where the relative integrated intensity of the first peak of the single metal of the first or second element, which has a lower content in the alloy, as determined by X-ray diffraction in the sputtering plane direction of the sputtering target, is 12% or less of the relative integrated intensity of the measured main peak" If, after dividing the sample into "locations where the relative integrated intensity of the first peak of the single metal with the lower content in the alloy exceeds 12% of the relative integrated intensity of the measured main peak," then four or more out of nine locations have "locations where the relative integrated intensity of the first peak of the single metal with the lower content in the alloy, either the first or second element, determined by X-ray diffraction in the sputtering plane direction of the sputtering target, is 12% or less of the relative integrated intensity of the measured main peak," then the condition that "40% or more locations have locations where the relative integrated intensity of the first peak of the single metal with the lower content in the alloy, either the first or second element, determined by X-ray diffraction in the sputtering plane direction of the sputtering target, is 12% or less of the relative integrated intensity of the measured main peak" is met.

[0050] Figure 1 is a schematic diagram showing the measurement points (hereinafter also referred to as measurement points) in the sputtering plane direction of a disc-shaped target. The measurement points in the sputtering plane direction of the sputtering target for (Condition 1) and (Condition 3) will be explained with reference to Figure 1. For a disc-shaped target, the radius is preferably 25 to 225 mm, and more preferably 50 to 200 mm. The thickness of the target is preferably 3 to 30 mm, and more preferably 5 to 26 mm. In this embodiment, greater effectiveness can be expected for larger targets.

[0051] (Condition 3) Sputtering plane direction: The sputtering target is a disc-shaped target with center O and radius r, and the measurement points are on a virtual crosshair that intersects with center O as the intersection point, with a total of 9 points: 1 point at center O, 4 points 0.45r away from center O, and 4 points 0.9r away from center O. Target thickness direction: A cross section is formed passing through one of the virtual crosshairs. This cross section is a rectangle with a length of t (i.e., the target thickness is t) and a width of 2r. The measurement points are defined as follows: a total of 9 points: the center X on the vertical cross section passing through the center O, and 3 points (points a, X, and b) located 0.45t above and below the center X; 2 points on the cross section 0.9r away from point a towards the left and right sides; 2 points 0.9r away from point X towards the left and right sides; and 2 points 0.9r away from point b towards the left and right sides.

[0052] In Figure 1, the sputtering target 200 is a disc-shaped target with center O and radius r. The measurement points are on a virtual crosshair (L) that intersects perpendicularly with center O as the intersection point, and consist of a total of 9 points: one point at center O (S1), four points 0.45r away from center O (S3, S5, S6, and S8), and four points 0.9r away from center O (S2, S4, S7, and S9).

[0053] Figure 2 is a schematic diagram showing the measurement locations in the target thickness direction of the disc-shaped target shown in the B-B cross-section of Figure 1. Referring to Figure 2, the measurement locations in the target thickness direction of the sputtering target under condition 3 will be explained.

[0054] In Figure 2, the BB cross section in Figure 1 is a rectangle with a vertical dimension t (i.e., the target thickness is t) and a horizontal dimension 2r. The measurement points are defined as follows: the center X (C1) on the vertical cross section passing through the center O shown in Figure 1, and a total of three points 0.45t above and below center X (point a (C4), point X (C1), and point b (C5)); a total of two points 0.9r away from point a toward the left and right sides on the cross section (C6, C7); a total of two points 0.9r away from point X toward the left and right sides (C2, C3); and a total of two points 0.9r away from point b toward the left and right sides (C8, C9), for a total of nine measurement points.

[0055] Figure 3 is a schematic diagram showing the measurement locations in the sputtering plane direction of a square plate-shaped target. The measurement locations in the sputtering plane direction of the sputtering target for (Condition 2) and (Condition 4) will be explained with reference to Figure 3. For rectangular or square targets, the vertical and horizontal lengths are preferably 50 to 450 mm, and more preferably 100 to 400 mm. The thickness of the target is preferably 3 to 30 mm, and more preferably 5 to 26 mm. In this embodiment, greater effectiveness can be expected for larger targets.

[0056] (Condition 4) Sputtering in-plane direction: The sputtering target is a rectangle with a vertical length of L1 and a horizontal length of L2 (including a square where L1 and L2 are equal. Alternatively, the rectangle includes a rectangle formed by unfolding the side surface of a cylinder with a length J and a perimeter K. In this form, L2 corresponds to the length J, L1 corresponds to the perimeter K, and the relationship between the length J and the perimeter K is J > K, J = K, or J < K). And the measurement points are nine in total, including one point at the center of gravity O, two points on the virtual cross-line perpendicular to each other with the center of gravity O as the intersection point, when the virtual cross-line is perpendicular to the sides of the rectangle, two points at a distance of 0.25L1 from the center of gravity O in the vertical direction, two points at a distance of 0.25L2 from the center of gravity O in the horizontal direction, two points at a distance of 0.45L1 from the center of gravity O in the vertical direction, and two points at a distance of 0.45L2 from the center of gravity O in the horizontal direction. Target thickness direction: Among the virtual cross-lines, a cross-section is formed by a line parallel to either one of the sides of the vertical L1 and the horizontal L2. When one side is the horizontal L2, the cross-section is a rectangle with a vertical length of t (i.e., the thickness of the target is t) and a horizontal length of L2. And the measurement points are nine in total, including the center X on the vertical cross-line passing through the center of gravity O and three points (referred to as point a, point X, and point b) at a distance of 0.45t above and below the center X, two points at a distance of 0.45L2 from point a towards the left and right side edges on the cross-section, two points at a distance of 0.45L2 from point X towards the left and right side edges, and two points at a distance of 0.45L2 from point b towards the left and right side edges.

[0057] The sputtering target 300 is a rectangular target with a vertical length of L1 and a horizontal length of L2 (including a square where L1 and L2 are equal). Figure 3 shows the sputtering target 300 in the form where L1=L2. The measurement points are a virtual crosshair (Q) that intersects perpendicularly with the centroid O as the intersection point. When the virtual crosshair is perpendicular to the sides of the rectangle (or square), there are a total of nine measurement points: one point at the centroid O (P1), two points on the virtual crosshair located 0.25L1 vertically from the centroid O (P6, P8), two points located 0.25L2 horizontally from the centroid O (P3, P5), two points located 0.45L1 vertically from the centroid O (P7, P9), and two points located 0.45L2 horizontally from the centroid O (P2, P4). Furthermore, if the sputtering target is rectangular, L1 and L2 can be selected as appropriate regardless of the length of the sides.

[0058] Figure 4 is a schematic diagram showing the measurement locations in the target thickness direction of a square plate-shaped target, as shown in the C-C cross-section of Figure 3. The measurement locations in the target thickness direction of the sputtering target under condition 4 will be explained with reference to Figure 4.

[0059] In Figure 4, the C-C section of Figure 3 forms a cross section passing through a line parallel to the horizontal side, and this cross section is a rectangle with vertical dimension t (i.e., the thickness of the target is t) and horizontal dimension L2. The measurement points are defined as a total of nine points: the center X on the vertical cross section passing through the centroid O, and three points 0.45t above and below the center X (point a (D4), point X (D1), and point b (D5)); two points on the cross section 0.45L2 away from point a toward the left and right sides (D6, D7); two points 0.45L2 away from point X toward the left and right sides (D2, D3); and two points 0.45L2 away from point b toward the left and right sides (D8, D9).

[0060] (Cylindrical sputtering target) FIG. 5 is a conceptual diagram for explaining measurement locations of a cylindrical target. When the sputtering target has a cylindrical shape, the side surface of the cylinder is the sputtering surface, and since the developed view is a rectangle (including a square), for (Condition 2) or (Condition 4), it can be considered in the same way as in FIGS. 3 and 4. The rectangle includes a rectangle obtained by developing the side surface of a cylinder with a length J and a circumference K. In this form, L2 corresponds to the length J, L1 corresponds to the circumference K, and the relationship of J > K, J = K, or J < K holds between the length J and the circumference K. In FIG. 5, when the sputtering target 400 has a cylindrical shape with a height (length) J and a body circumference K, consider the E-E cross-section and the D-D developed surface with the cross-section at both ends. First, for the measurement locations in the target thickness direction, consider it in the same way as in FIG. 4 in the E-E cross-section. That is, assume that the height J of the cylindrical material corresponds to L2 in FIG. 4 and the thickness of the cylindrical material corresponds to the thickness t in FIG. 4, and use this as the measurement location. Also, for the measurement locations in the sputtering surface direction, consider it in the same way as in FIG. 3 in the D-D developed surface. That is, assume that the height J of the cylindrical material corresponds to L2 in FIG. 3 and the body circumference K of the cylindrical material corresponds to L1 in FIG. 3, and use this as the measurement location. In the case of a cylindrical target, the length of the body circumference of the cylinder is preferably 100 to 350 mm, more preferably 150 to 300 mm. The length of the cylinder is preferably 300 to 3000 mm, more preferably 500 to 2000 mm. The thickness of the target is preferably 3 to 30 mm, more preferably 5 to 26 mm. In this embodiment, more effects can be expected for large targets.

[0061] The sputtering target according to this embodiment preferably has an oxygen content of 500 ppm or less, more preferably 400 ppm or less, and even more preferably 300 ppm or less. When the oxygen content is more than 500 ppm, oxygen combines with the added components in the target to form oxides of the added elements, resulting in particles being mixed into the film when forming a thin film using the target, or the sputtering rate varying depending on the location, and abnormal discharge occurring, causing particles to be mixed into the film. Therefore, it is preferable to set the oxygen content to 500 ppm or less.

[0062] The sputtering target according to this embodiment preferably has a carbon content of 200 ppm or less, more preferably 150 ppm or less, and even more preferably 100 ppm or less. If the carbon content is higher than 200 ppm, the added components in the target will combine with the carbon to form carbides of the added elements, which can lead to particle contamination in the film when a thin film is formed using the target, or to particle contamination in the film due to abnormal discharge occurring because the sputtering rate differs in different locations. Therefore, it is preferable to keep the carbon content at 200 ppm or less.

[0063] In this specification, the term "ruthenium matrix" can be interpreted as "ruthenium matrix." Figure 6 illustrates the concept of the ruthenium matrix using the structure of the first embodiment as an example. In the sputtering target 100, the microstructure consists of a ruthenium matrix containing a material with ruthenium and a second element, specifically, a Ru-AE alloy. That is, the Ru matrix 3 binds together multiple Ru-AE alloy particles 1. The Ru-AE alloy particles 1 are aggregates of Ru-AE alloy crystal grains 2. The boundary between a Ru-AE alloy crystal grain 2a and an adjacent Ru-AE alloy crystal grain 2b is a grain boundary. Crystal grains 2a and adjacent crystal grains 2b may have the same composition or different compositions. The Ru matrix 3 is an aggregate of ruthenium crystal grains 4. The boundary between a ruthenium crystal grain 4a and an adjacent ruthenium crystal grain 4b is a grain boundary. Thus, in this specification, the term "matrix phase" refers to the phase that binds together multiple metal particles or alloy particles, and the binding phase itself is a concept that is an aggregate of crystal grains. [Examples]

[0064] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to the examples.

[0065] (Example 1) Ru raw material with a purity of 3N5up and Zr raw material with a purity of 3N are put into the powder manufacturing device, and then the inside of the powder manufacturing device is processed in 5 × 10⁻¹⁰⁻¹ -3 The atmosphere was adjusted to a vacuum of Pa or less, and the Ru and Zr raw materials were melted at a melting temperature of 1900°C to form a molten metal. Then, argon gas was blown onto the molten metal, causing it to splatter and rapidly solidify to produce Ru-20 atom %Zr powder with a maximum major diameter of 500 μm or less (in this case, Ru is 80 atom %Ru, but the atomic percentage of Ru is omitted. The same applies hereafter). Here, the Ru-20 atom %Zr powder with a maximum major diameter of 500 μm or less was adjusted by classification. Next, Ru powder with a purity of 3N was prepared separately, and the weight of the Ru-20 atom %Zr powder and Ru powder was adjusted so that it would be Ru-15 atom %Zr. Then, the mixture was mixed for 30 minutes using a V-type mixer to produce a mixed powder, and the mixed powder was packed into a carbon mold for discharge plasma sintering (hereinafter also called SPS sintering). Next, the mixed powder was sealed in a mold and punch under a pre-pressurized pressure of 30 MPa, and the mold filled with the mixed powder was placed in an SPS apparatus (model number: SPS-825, manufactured by SPS Syntex Co., Ltd.). Sintering was then carried out under the following conditions: a sintering temperature of 1250°C, a pressurized pressure of 55 MPa, and a vacuum atmosphere of 20 Pa or less inside the sintering apparatus. The Ru-15 atomic %Zr sintered body was processed using a grinding machine, lathe, etc., to produce the Φ50.8 mm × 5 mmt Ru-15 atomic %Zr target of Example 1.

[0066] (Example 2) Ru raw material with a purity of 3N5up and Ta raw material with a purity of 3N are put into the powder manufacturing device, and then the inside of the powder manufacturing device is processed in 5 × 10 -3Adjusted to a vacuum atmosphere of less than Pa, melted Ru raw material and Ta raw material at a melting temperature of 2500 °C to obtain a molten metal, and then blew argon gas onto the molten metal to scatter the molten metal and rapidly solidify it to produce Ru-40 atomic % Ta powder with a maximum major diameter of 500 μm or less. Here, the Ru-40 atomic % Ta powder with a maximum major diameter of 500 μm or less was adjusted by classification. Next, Ru powder with a purity of 3N was separately prepared, and after adjusting the weights of the Ru-40 atomic % Ta powder and the Ru powder so as to obtain Ru-25 atomic % Ta, mixing was performed for 30 minutes using a V-type mixer to produce a mixed powder, and the mixed powder was filled into a carbon mold for spark plasma sintering (hereinafter also referred to as SPS sintering). Next, the mixed powder was sealed with a mold and a punch, etc. under a preliminary pressure of 30 MPa, and the mold filled with the mixed powder was installed in an SPS apparatus (model number: SPS-825, manufactured by SPS Syntex). Then, as sintering conditions, sintering was carried out under the conditions of a sintering temperature of 1400 °C, a pressure of 55 MPa, and a vacuum atmosphere of 20 Pa or less in the sintering apparatus. The Ru-25 atomic % Ta sintered body was processed using a grinding machine, a lathe, etc. to produce a Ru-25 atomic % Ta target of Φ50.8 mm × 5 mmt of Example 2.

[0067] (Example 3) Ru raw material with a purity of 3N5up and Ti raw material with a purity of 3N were put into a powder manufacturing apparatus. Next, the inside of the powder manufacturing apparatus was set to 5×10 -3The atmosphere was adjusted to a vacuum of less than Pa, and the Ru and Ti raw materials were melted at a melting temperature of 1900°C to form a molten metal. Then, argon gas was blown onto the molten metal to scatter it and rapidly cool and solidify it to produce Ru-28 atomic %Ti powder with a maximum major diameter of 500 μm or less. Here, the Ru-28 atomic %Ti powder with a maximum major diameter of 500 μm or less was adjusted by classification. Next, Ru powder with a purity of 3N was prepared separately, and the weight of the Ru-28 atomic %Ti powder and Ru powder was adjusted to produce Ru-5 atomic %Ti. Then, the mixture was mixed for 30 minutes using a V-type mixer to produce a mixed powder, and the mixed powder was filled into a carbon mold for discharge plasma sintering (hereinafter also referred to as SPS sintering). Next, the mixed powder was sealed in the mold and punched with a pre-pressurized 30 MPa, and the mold filled with the mixed powder was placed in an SPS apparatus (model number: SPS-825, manufactured by SPS Syntex Co., Ltd.). The sintering conditions were set to a sintering temperature of 1150°C, a pressurized pressure of 55 MPa, and a vacuum atmosphere of 20 Pa or less inside the sintering apparatus. The Ru-5 atom %Ti sintered body was processed using a grinding machine, lathe, etc., to produce the Φ50.8 mm × 5 mmt Ru-5 atom %Ti target of Example 3.

[0068] (Comparative Example 1) In Example 1, instead of blowing argon gas onto the molten metal and rapidly cooling and solidifying the molten metal to produce Ru-20 atom %Zr powder with a maximum major diameter of 500 μm or less, Ru-20 atom %Zr powder with a maximum major diameter of 500 μm or more was produced by blowing argon gas onto the molten metal and rapidly cooling and solidifying the molten metal to produce Ru-20 atom %Zr powder with a maximum major diameter of 500 μm or more. Otherwise, a Ru-15 atom %Zr sintered body was obtained in the same manner as in Example 1. Here, the Ru-20 atom %Zr powder with a maximum major diameter of 500 μm or more was adjusted by classification. When attempting to process the Ru-15 atom %Zr sintered body using a grinding machine, chipping occurred on the outer circumference of the plate during grinding, and cracks occurred in the plate starting from the chipping, making it impossible to produce a sputtering target.

[0069] (Comparative Example 2) Pure Ru powder with a particle size of 100 μm or less and a purity of 3N5up, and Zr powder with a particle size of 100 μm or less and a purity of 3N5up were mixed after adjusting the amount of each powder to obtain Ru-15 atoms %Zr. Then, a Ru-15 atoms %Zr sintered body was prepared in the same manner as in Example 1. The sintered Ru-15 atoms %Zr sintered body was processed using a grinding machine, lathe, etc., to produce a Ru-15 atoms %Zr target of Comparative Example 2 with a diameter of Φ50.8 mm and a thickness of 5 mm.

[0070] (Comparative Example 3) Ru raw material with a purity of 3N5up and Zr raw material with a purity of 3N were weighed to a ratio of Ru-15 atomic%Zr, and melted in an arc melting apparatus (ULVAC AME-300 model) to obtain a molten plate approximately 60mm square x 6mm in size. Next, an attempt was made to machine this plate to create a sputtering target of Φ50.8mm x 5mmt, but chipping occurred on the outer edge of the plate during grinding, and cracks occurred in the plate during cutting by wire electrical discharge machining, making it impossible to create a sputtering target.

[0071] (Comparative Example 4) Pure Ru powder with a particle size of 100 μm or less and a purity of 3N5 or higher, and Ta powder with a particle size of 100 μm or less and a purity of 3N5 or higher were mixed after adjusting the amount of each powder to achieve a Ru-25 atomic %Ta composition. Subsequently, a Ru-25 atomic %Ta sintered body was prepared in the same manner as in Example 2. The sintered Ru-25 atomic %Ta sintered body was processed using a grinding machine, lathe, etc., to produce a Φ50.8 mm × 5 mmt Ru-25 atomic %Ta target for Comparative Example 4.

[0072] (Maximum diameter of dispersed particles observed by SEM) For the targets of Examples 1-3, Comparative Examples 1, 2, and 4, the maximum major axis of dispersed particles was measured by direct observation within a 1200 μm × 1500 μm SEM image using an electron microscope (model JSM-6010: JEOL). The measurement results are shown in Table 1. The observations showed that the maximum major axis of dispersed particles in Example 1 was 120 μm, in Example 2 it was 200 μm, and in Example 3 it was 200 μm, confirming that dispersed particles were dispersed within the sputtering target. On the other hand, the maximum major axis of dispersed particles in Comparative Example 1 was 1000 μm, in Comparative Example 2 it was 64 μm, and in Comparative Example 4 it was 80 μm.

[0073] [Table 1]

[0074] (Filling rate) The packing density of the targets for Examples 1-3, Comparative Example 1, Comparative Example 2, and Comparative Example 4 was calculated using the Archimedes method. The calculation results are shown in Table 2. The packing density was calculated by dividing the (measured density of the sintered body measured by the Archimedes method) by the (theoretical density of the sintered body) and then multiplying by 100 to convert it to a percentage. The packing density of Example 1 was 100%, Example 2 was 99.8%, and Example 3 was 99.9%, resulting in sputtering targets with high packing density and few voids. In contrast, the packing density of Comparative Example 1 was 78.6%, resulting in a sputtering target with low packing density and many voids. The packing density of Comparative Example 2 was 96%, and the packing density of Comparative Example 4 was 98.4%, resulting in sputtering targets with high packing density and few voids.

[0075] [Table 2]

[0076] (Content analysis by EDS) For the targets of Examples 1-3, Comparative Example 2, and Comparative Example 4, the content of each additive element S1-S9 in Figure 1 and the content of each additive element C1-C9 in Figure 2 were analyzed by energy-dispersive X-ray spectroscopy (EDS). The measurement range was 700 μm × 900 μm. The measurement results are shown in Tables 3-6 and 9-14. From Table 3, the average Zr content of S1-S9 in Example 1 was 15.03%, and the difference between the Zr content at each point S1-S9 and the average Zr content of S1-S9 was a maximum of 0.41 and a minimum of 0.04 in Example 1. Table 3 shows that the average Zr content of C1-C9 in Example 1 was 15.11%, and the difference between the Zr content at each point C1-C9 and the average Zr content of C1-C9 was a maximum of 0.52 and a minimum of 0.01 in Example 1. The target in Example 1 showed little variation in composition due to location, both in the sputtering plane direction and in the target thickness direction. Furthermore, Table 4 shows that the average Zr content of S1-S9 and C1-C9 in Example 1 was 15.07%, and the difference between the Zr content at each point S1-S9 and C1-C9 and the average Zr content of S1-S9 and C1-C9 was a maximum of 0.48 and a minimum of 0.00 in Example 1. The target in Example 1 showed small compositional deviations at each point, meaning that there were small compositional deviations due to differences in location in the in-plane direction and the thickness direction of the target.

[0077] Table 9 shows that the average Ta content of S1 to S9 in Example 2 was 25.20%, and the difference between the Ta content at each point S1 to S9 and the average Ta content of S1 to S9 was a maximum of 0.81 and a minimum of 0.04 in Example 2. Table 9 also shows that the average Ta content of C1 to C9 in Example 2 was 24.92%, and the difference between the Ta content at each point C1 to C9 and the average Ta content of C1 to C9 was a maximum of 1.06 and a minimum of 0.05 in Example 2. The target in Example 2 showed little variation in composition due to location, both in the sputtering plane direction and in the target thickness direction. Furthermore, as shown in Table 10, the average Ta content of S1-S9 and C1-C9 in Example 2 was 25.06%, and the difference between the Ta content at each point of S1-S9 and C1-C9 and the average Ta content of S1-S9 and C1-C9 was a maximum of 0.93 and a minimum of 0.07 in Example 2. The target in Example 2 showed small compositional deviations at each point, meaning that there were small compositional deviations due to differences in location in the in-plane direction and thickness direction of the target.

[0078] From Table 11, the average Ti content of S1 to S9 in Example 3 was 5.18%, and the difference between the Ti content at each point S1 to S9 and the average Ti content of S1 to S9 was a maximum of 1.12 and a minimum of 0.07 in Example 3. From Table 11, the average Ti content of C1 to C9 in Example 3 was 5.10%, and the difference between the Ti content at each point C1 to C9 and the average Ti content of C1 to C9 was a maximum of 0.91 and a minimum of 0.34 in Example 3. The target in Example 3 showed little variation in composition due to location, both in the sputtering plane direction and in the target thickness direction. Furthermore, as shown in Table 12, the average Ti content of S1-S9 and C1-C9 in Example 3 was 5.14%, and the difference between the Ti content at each point of S1-S9 and C1-C9 and the average Ti content of S1-S9 and C1-C9 was a maximum of 1.07 and a minimum of 0.11 in Example 3. The target in Example 3 showed small compositional deviations at each point, meaning that there were small compositional deviations due to differences in location in the in-plane direction and thickness direction of the target.

[0079] On the other hand, as shown in Table 5, the average Zr content of S1 to S9 in Comparative Example 2 was 14.88%, and the difference between the Zr content at each point S1 to S9 and the average Zr content of S1 to S9 was a maximum of 0.99 and a minimum of 0.13 in Comparative Example 2. As shown in Table 5, the average Zr content of C1 to C9 in Comparative Example 2 was 14.55%, and the difference between the Zr content at each point C1 to C9 and the average Zr content of C1 to C9 was a maximum of 1.18 and a minimum of 0.01 in Comparative Example 2. The target in Comparative Example 2 showed small deviations in composition due to location, both in the sputtering plane direction and in the target thickness direction. Furthermore, as shown in Table 6, the average Zr content of S1-S9 and C1-C9 in Comparative Example 2 was 14.72%, and the difference between the Zr content at each point of S1-S9 and C1-C9 and the average Zr content of S1-S9 and C1-C9 was a maximum of 1.15 and a minimum of 0.03 in Comparative Example 2. The target of Comparative Example 2 showed small compositional deviations at each point, that is, there were small compositional deviations due to differences in location in the in-plane direction and thickness direction of the target.

[0080] Table 13 shows that the average Ta content of S1 to S9 in Comparative Example 4 was 24.90%, and the difference between the Ta content at each point S1 to S9 and the average Ta content of S1 to S9 was a maximum of 0.79 and a minimum of 0.02 in Comparative Example 4. Table 13 also shows that the average Ta content of C1 to C9 in Comparative Example 4 was 24.93%, and the difference between the Ta content at each point C1 to C9 and the average Ta content of C1 to C9 was a maximum of 0.85 and a minimum of 0.06 in Comparative Example 4. The target in Comparative Example 4 showed small variations in composition due to location, both in the sputtering plane direction and in the target thickness direction. Furthermore, as shown in Table 14, the average Ta content of S1-S9 and C1-C9 in Comparative Example 4 was 24.91%, and the difference between the Ta content at each point of S1-S9 and C1-C9 and the average Ta content of S1-S9 and C1-C9 was a maximum of 0.87 and a minimum of 0.03 in Comparative Example 4. The target of Comparative Example 4 showed small compositional deviations at each point, that is, there were small compositional deviations due to differences in location in the in-plane direction and thickness direction of the target.

[0081] Table 3

[0082] Table 4

[0083] Table 5

[0084] Table 6

[0085] Table 9

[0086] Table 10

[0087] Table 11

[0088] Table 12

[0089] Table 13

[0090] Table 14

[0091] (XRD intensity) X-ray diffraction was performed on the targets of Examples 1-3, Comparative Example 2, and Comparative Example 4 at locations S1-S9 of (Condition 1). The relative integrated intensity of the main peak for CuKα, 2θ=20-90° was compared with the relative integrated intensity of the first peak of the monometallic second element (hereinafter referred to as the first peak), and the ratio of the relative integrated intensity of the first peak to the relative integrated intensity of the main peak was calculated. The calculation results are shown in Table 7. In Example 1, the ratio of the relative integrated intensity of the first peak to the relative integrated intensity of the main peak was 7.9-8.4%, in Example 2 it was 0-0.1%, and in Example 3 it was 0%. Since the relative integrated intensity of the first peak was 12% or less of the relative integrated intensity of the main peak at all locations, it was confirmed that the sputtering targets of Examples 1-3 had a low proportion of the second element existing as a monometal, and the contamination of particles due to the scattering of the second element itself during film formation was suppressed. In Comparative Example 2, the ratio of the relative integrated intensity of the first peak to the relative integrated intensity of the main peak was 14.0-14.7%, and in Comparative Example 4, it was 20.0-20.6%. Since the relative integrated intensity of the first peak was greater than 12% of the relative integrated intensity of the main peak, it was confirmed that the sputtering targets in Comparative Example 2 and Comparative Example 4 had a high proportion of the second element existing as a single metal, resulting in particle contamination due to the scattering of the second element itself during film formation.

[0092] [Table 7]

[0093] (Oxygen and carbon content) The oxygen and carbon content of the targets for Examples 1-3, Comparative Example 2, and Comparative Example 4 was measured using a mass spectrometer (Model: Element GD, Thermo Fisher Scientific). The measurement results are shown in Table 8. Example 1 had an oxygen content of 218 ppm and a carbon content of 17 ppm, indicating low oxygen and carbon content. Example 2 had an oxygen content of 159 ppm and a carbon content of 12 ppm, indicating low oxygen and carbon content. Example 3 had an oxygen content of 88 ppm and a carbon content of 6 ppm, indicating low oxygen and carbon content. Therefore, it is possible to disperse the additive elements in the ruthenium alloy target while suppressing oxidation and carbonization of the additive elements, and when a film is formed using this target, a film with reduced particles can be obtained by suppressing abnormal discharges caused by oxidized or carbonized additive elements. On the other hand, Comparative Example 2 had an oxygen content of 1117 ppm and a carbon content of 41 ppm, indicating a high oxygen content. Comparative Example 4 had an oxygen content of 704 ppm and a carbon content of 17 ppm, indicating a high oxygen content. Therefore, when the target was heated during film formation, the added components in the target combined with oxygen to form oxides. As a result, when a thin film was formed using the target, the sputtering rate varied from place to place, leading to variations in film thickness.

[0094] [Table 8]

[0095] From the results of Examples 1-3 and Comparative Examples 1-4, it was found that in Examples 1-3, the maximum major diameter of the dispersed particles, the packing density, the compositional deviation, the ratio of the relative integrated intensity of the first peak of the single metal with the lower content in the alloy to the relative integrated intensity of the main peak, the oxygen content, and the carbon content all satisfied the specified values. Therefore, oxidation and carbonization of the additive elements could be suppressed, and when a film was deposited using the target, abnormal discharges caused by oxidized or carbonized additive elements were suppressed, resulting in a film with reduced particles. Furthermore, by manufacturing the sputtering target while suppressing the single metal areas of the additive elements, a sputtering target with suppressed compositional deviations depending on the area could be obtained. When a film was deposited using the target, the deviation of the sputtering rate between the alloy areas and the single metal areas of the additive elements was suppressed, and abnormal discharges occurring between the alloy and the single metals were suppressed, resulting in a film with reduced particles due to the single metals. On the other hand, in Comparative Example 1, the maximum major diameter of the dispersed particles was large and the packing density was low, so cracks occurred during grinding and the film could not be manufactured. In Comparative Example 2, the ratio of the relative integral intensity of the first peak of the single metal with a lower content in the alloy to the relative integral intensity of the main peak was large, confirming that a large proportion of the second element existed as a single metal, resulting in particle contamination due to the scattering of the second element itself during film formation. In addition, due to the high oxygen content, variations in film thickness occurred when the film was formed using a sputtering target. In Comparative Example 3, the molten ruthenium was too hard, causing cracks during grinding and cutting processes, making fabrication impossible. In Comparative Example 4, the ratio of the relative integral intensity of the first peak of the single metal with a lower content in the alloy to the relative integral intensity of the main peak was large, confirming that a large proportion of the second element existed as a single metal, resulting in particle contamination due to the scattering of the second element itself during film formation. In addition, due to the high oxygen content, variations in film thickness occurred when the film was formed using a sputtering target. [Explanation of symbols]

[0096] 100, 200, 300, 400 Sputtering Targets O center, center of gravity L,Q virtual crosshairs S1~S9 Measurement points in the direction within the sputtering plane C1~C9 Measurement points in the target thickness direction P1~P9 Measurement points in the direction within the sputtering surface D1~D9 Measurement points in the target thickness direction 1 Ru-AE alloy particles 3 Ru matrix 2,2a,2b Crystal grains of Ru-AE alloy 4,4a,4b Ruthenium crystal grains

Claims

1. In a method for manufacturing a sputtering target of an alloy composed of ruthenium as the first element and one selected from boron, titanium, zirconium, hafnium, vanadium, niobium, tantalum, molybdenum, and tungsten as the second element, A preparation step of preparing raw materials in which the first element and the second element are in a predetermined elemental ratio, 1 x 10 －２ An atomization step to obtain alloy powder by atomization using the raw materials in a vacuum atmosphere of Pa or less, a nitrogen gas atmosphere containing 0 to 4 vol% or less of hydrogen gas, or an inert gas atmosphere containing 0 to 4 vol% or less of hydrogen gas, A mixing step is to further add a ruthenium raw material to the alloy powder to obtain a mixture, The process includes a sintering step to obtain a sintered body by sintering the mixture using a hot press method, a discharge plasma sintering method (SPS), or a hot isostatic sintering method (HIP) in a vacuum atmosphere of 50 Pa or less, a nitrogen gas atmosphere containing 0 to 4 vol% or less of hydrogen gas, or an inert gas atmosphere containing 0 to 4 vol% or less of hydrogen gas. A method for manufacturing a sputtering target, characterized in that the maximum major diameter of the alloy powder obtained by the atomization method is 500 μm or less.

2. Between the atomization step and the mixing step, The method for manufacturing a sputtering target according to claim 1, further comprising a classification step of removing particles with a maximum major diameter exceeding 500 μm from the alloy powder obtained by the atomization method.

3. The method for manufacturing a sputtering target according to claim 1 or 2, characterized in that the filling rate of the sputtering target is 80% or more.

4. The ruthenium raw material is 1 × 10 －２ A method for producing a sputtering target according to any one of claims 1 to 3, characterized in that the ruthenium powder is obtained by an atomization method carried out in a vacuum atmosphere of Pa or less, a nitrogen gas atmosphere containing 0 to 4 vol% or less of hydrogen gas, or an inert gas atmosphere containing 0 to 4 vol% or less of hydrogen gas.

5. A method for manufacturing a sputtering target according to any one of claims 1 to 4, characterized in that the content of the second element is 3 to 70 atomic percent.

6. In a sputtering target of an alloy composed of ruthenium as the first element and one selected from boron, aluminum, titanium, zirconium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, and tungsten as the second element, The sputtering target has dispersed particles composed of two phases, including an intermetallic compound phase consisting of two elements, the first element and the second element, in a ruthenium matrix. A sputtering target characterized in that the maximum major axis of the dispersed particles is 500 μm or less.

7. The sputtering target according to claim 6, characterized in that the two phases are (1) a combination of the intermetallic compound phase and a metallic ruthenium phase which is the metallic phase of the first element, (2) a combination of two types of the intermetallic compound phases, or (3) a combination of the intermetallic compound phase and the metallic phase which is the metallic phase of the second element.

8. In a sputtering target of an alloy composed of ruthenium as the first element and one selected from boron, zirconium, vanadium, niobium, chromium, molybdenum, and tungsten as the second element, The sputtering target has dispersed particles in a ruthenium matrix, which consists of a phase of intermetallic compound composed of two elements, the first element and the second element. A sputtering target characterized in that the maximum major axis of the dispersed particles is 500 μm or less.

9. The sputtering target according to any one of 6 to 8, characterized in that, in (Condition 1) or (Condition 2), there is at least one location where the relative integrated intensity of the first peak of the single metal of the first element or the second element which has a lower content in the alloy, as determined by X-ray diffraction in the direction in the sputtering plane of the sputtering target, is 12% or less of the relative integrated intensity of the main peak measured. (Condition 1) Sputtering plane direction: The sputtering target is a disc-shaped target with a center O and radius r, and the measurement points are on a virtual crosshair that intersects with the center O as the intersection point, with a total of 9 points: one point at the center O, a total of 4 points 0.45r away from the center O, and a total of 4 points 0.9r away from the center O. (Condition 2) Direction within the sputtering plane: The sputtering target is a rectangle with a vertical length of L1 and a horizontal length of L2 (however, this includes a square where L1 and L2 are equal. Alternatively, the rectangle includes a rectangle formed by unfolding the side surface of a cylindrical shape with length J and circumference K, in which case L2 corresponds to length J and L1 corresponds to circumference K, and the relationship J>K, J=K, or J<K holds between length J and circumference K). The measurement points are a total of nine points, where the centroid O is the intersection point of a virtual crosshair that is orthogonal to the sides of the rectangle, there is one point at the centroid O, a total of two points on the virtual crosshair located 0.25L1 vertically from the centroid O, a total of two points located 0.25L2 horizontally from the centroid O, a total of two points located 0.45L1 vertically from the centroid O, and a total of two points located 0.45L2 horizontally from the centroid O.

10. The sputtering target according to claim 9, characterized in that, in (Condition 1) or (Condition 2), there are 40% or more locations where the relative integrated intensity of the first peak of the single metal of the first element or the second element which has a lower content in the alloy, as determined by X-ray diffraction in the direction in the sputtering plane of the sputtering target, is 12% or less of the relative integrated intensity of the main peak measured.

11. A sputtering target according to any one of 6 to 10, characterized in that it has an oxygen content of 500 ppm or less.

12. A sputtering target according to any one of 6 to 11, characterized in that the carbon content is 200 ppm or less.

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