TW202317793A - Hard nitride-containing sputtering target - Google Patents

Abstract

Provided are: a hard nitride-containing sputtering target that can prevent the occurrence of arcing during sputtering, caused by inclusion of relatively course zirconia particles, and can suppress the generation of particles during film formation; and a production method therefor. The hard nitride-containing sputtering target: comprises an alloy phase including Fe or Co and a non-magnetic phase including a hard nitride selected from AlN, BN, Cr2N, Si3N4, HfN, NbN, TaN, TiN, VN, or any combination of these; and is characterized by having a Zr impurities concentration, when measured as metallic Zr, that is restricted to no more than 1,000 ppm and a Vickers hardness Hv of 200-600 when measured under a 3 kgf load.

Description

Sputtering targets containing hard nitrides

The present invention relates to a sputtering target containing hard nitrides and a manufacturing method thereof, in particular to a sputtering target containing hard nitrides, which is composed of an alloy phase containing Fe or Co and containing an alloy phase selected from AlN, BN, Cr ₂ N, Si ₃ N ₄ , HfN, NbN, TaN, TiN, VN, and any combination of these non-magnetic phases of hard nitrides, and related manufacturing methods.

As a sputtering target for the grain-structured magnetic thin film used in the manufacture of magnetic recording media such as hard disk drives, alloy phases containing ferromagnetic metals such as Fe or Co as the main component and oxides, carbon, boron nitride, etc. are used. Sintered body of non-magnetic material.

In a sputtering target containing oxide as a non-magnetic material, it has been confirmed that particle generation during film formation can be reduced by making a non-magnetic material particle-dispersed structure in which oxides are uniformly and finely dispersed between alloy phases. In order to uniformly and finely disperse the oxides between the alloy phases, use a media agitation mill such as a zirconia ball mill to carry out strong stirring, and mix the oxides with the raw material powders that form the alloy phase (Japanese Patent No. 4673448, Japan Patent No. 6728094). Sputtering targets containing nitrides instead of oxides are also proposed, but the method of vigorously stirring and mixing using a zirconia ball mill is the same as that of oxides (Japanese Patent No. 5913620, Japanese Patent No. 6526837).

Japanese Patent No. 4673448 discloses a non-magnetic particle-dispersed ferromagnetic material sputtering target, which has a phase (A) in which non-magnetic particles of oxides are uniformly and finely dispersed and a diameter of 50 to 200 μm in the phase (A) The spherical alloy phase (B) has a composition in which Cr is concentrated by 25 mol% or more near the center of the spherical alloy phase (B), and the Cr content in the outer peripheral portion is lower than that in the central portion. It is also described that the sputtering target system is made by enclosing metal powder with a maximum particle size of 20 μm or less, non-magnetic material powder with a maximum particle size of 5 μm or less, and zirconia balls in a ball mill tank with a capacity of 10 liters, and rotating for 20 hours. It is pulverized and mixed, and the mixed powder is mixed with Co-Cr spherical powder with a diameter of 50-200 μm in a planetary mixer, and manufactured by sintering.

Japanese Patent No. 6728094 discloses the invention of including Co-Pt phase, Co phase and non-magnetic material in order to suppress the generation of particles during sputtering, making the Co-Pt alloy phase finer and Co phase coarser. Specifically, it is described that the average particle size of the Co-Pt alloy phase is set to be 0.1 μm to 7 μm, the average particle size of the Co phase is set to be 30 μm to 300 μm, and the average particle size of the non-magnetic oxide material is set to be 0.05 μm to 2 μm, Co-Pt alloy powder with a median diameter of 0.1 μm to 7 μm, and non-magnetic material powder with a median diameter of 0.05 μm to 2 μm are used as raw materials. In addition, as a mixing method of the raw material powder, it is described that the raw material powder is sealed together with zirconia balls in a ball mill with a capacity of 10 liters, and mixed by rotating for 20 hours.

Japanese Patent No. 5913620 discloses that in the Fe-Pt sintered body sputtering target using hexagonal BN as a non-magnetic material, the abnormal discharge in sputtering can be suppressed by improving the alignment of hexagonal BN, reducing the The amount of particles that occur. Specifically, it is described that Fe-Pt alloy powder and zirconia balls are put into a media agitation mill with a capacity of 5 L, treated at a rotation speed of 300 rpm for 2 hours, and after making Fe-Pt alloy powder with an average particle size of 10 μm, Fe- The Pt alloy powder and the hexagonal BN powder were mixed with a V-type mixer, and further mixed using a 150 μm sieve. However, the hardness of the hexagonal BN system is low, the hardness as a sputtering target is insufficient, and there is a problem that cracks occur during sputtering.

Japanese Patent No. 6526837 discloses an Fe-Pt-based sputtering target and a Co-Pt-based sputtering target using cubic BN, which is less likely to cause cracks in BN particles than hexagonal BN, and describes that the raw material powder Put them together with zirconia balls into a medium-stirred mill with a capacity of 5 L, mix them by rotating (300 rpm) for 2 hours, and pulverize until the median diameter (D50) of the raw material mixed powder is 0.3 μm or more and 20 μm or less, preferably pulverized to 5μm or less.

However, according to the experiments of the inventors of the present invention, it is known that when using nitrides as the non-magnetic material, when the raw material powders are mixed, since the nitrides are hard, the zirconia balls or the inner wall of the media agitated mill will be worn and damaged. Coarse zirconia particles are mixed in. Since the resistivity of coarse zirconia particles is higher than that of nitrides and carbides, arcs are likely to be caused during sputtering, and particles are likely to be generated during film formation. [Prior Art Literature] [Patent Document]

[Patent Document 1] Japanese Patent No. 4673448 [Patent Document 2] Japanese Patent No. 6728094 [Patent Document 3] Japanese Patent No. 5913620 [Patent Document 4] Japanese Patent No. 6526837

[Problem to be solved by the invention]

In order to solve the above-mentioned conventional problems, the present invention aims to provide a hard nitride-containing sputtering target that prevents the occurrence of arc in sputtering due to the mixing of relatively coarse zirconia particles, and can suppress the generation of particles during film formation, and its production. method. [Means to solve the problem]

The inventors of the present invention found that the arc in the sputtering of the sputtering target containing hard nitride is caused by the mixed presence of relatively coarse zirconia particles. The zirconia impurity particles in the zirconia ball mill used are considered to suppress arcing during sputtering, and thus the present invention has been accomplished.

According to the present invention, there is provided a sputtering target containing hard nitride, which is characterized by an alloy phase comprising Fe or Co, and comprising AlN, BN, Cr ₂ N, Si ₃ N ₄ , HfN, NbN, TaN, It is composed of non-magnetic phases of hard nitrides in TiN, VN, and any combination thereof. The Zr impurity concentration is limited to less than 1000ppm when measured by metal Zr. The Vickers (Vickers) hardness Hv measured under a load of 3kgf 200 to 600.

The aforementioned Zr impurity concentration is preferably limited to 500 ppm or less.

The aforementioned nonmagnetic phase preferably satisfies at least one of the following: The average particle size obtained by image analysis of the observation field of view 180 μm × 180 μm of EPMA surface analysis at a magnification of 500 is 4 μm to 20 μm; The average particle size obtained by image analysis of the observation field of view of EPMA surface analysis at a magnification of 1000 of 90 μm × 90 μm is not less than 2 μm and not more than 20 μm; and The average particle size obtained by image analysis of the observation field of view 30 μm×30 μm of EPMA surface analysis at a magnification of 3000 is 1 μm to 20 μm.

The content of the said nonmagnetic phase in the said sputtering target is 5 mol% or more and 50 mol% or less.

The non-magnetic phase may further contain one or more selected from C, B ₂ O ₃ and SiO ₂ .

The aforementioned alloy phase contains Pt in an amount of not less than 0 mol % and not more than 60 mol %.

The aforementioned alloy phase may further contain one or more elements selected from the group consisting of Ag, Au, Cr, Cu, Ge, Ir, Ni, Pd, Rh, Ru, and B.

According to the present invention, a method for manufacturing the aforementioned sputtering target containing hard nitride is also provided. The production method of the present invention is characterized in that it includes using a zirconia ball mill at a rotation speed of 50 rpm to 150 rpm, mixing the raw material powders constituting the aforementioned alloy phase and the aforementioned non-magnetic phase for 2 hours to 6 hours to prepare a mixed powder, and mixing the aforementioned Powder sintering.

The raw material powders constituting the aforementioned alloy phase are preferably metal powders of the respective raw materials or Fe-based or Co-based atomized alloy powders.

The raw material powder constituting the non-magnetic phase preferably includes hard nitride powder having an average particle diameter D50 of 1 μm or more and 40 μm or less. [Invention effect]

The sputtering target containing hard nitride of the present invention prevents the mixing of relatively coarse zirconia impurity particles with high resistivity, and limits the Zr impurity concentration when measured with metal Zr to below 1000ppm, so suppresses sputtering during sputtering. Arc generation can reduce the particles originating from zirconia particles during film formation.

Hereinafter, the present invention will be described in more detail with reference to the accompanying drawings. The feature of the sputtering target containing hard nitride of the present invention is that the alloy phase comprising Fe or Co and comprising AlN, BN, Cr ₂ N, Si ₃ N ₄ , HfN, NbN, TaN, TiN, VN and the It is formed by the non-magnetic phase of hard nitride in any combination of metal Zr, and the Zr impurity concentration is limited to less than 1000ppm, preferably less than 500ppm, more preferably less than 300ppm, under a load of 3kgf The measured Vickers hardness Hv is not less than 200 and not more than 600, preferably not less than 250 and not more than 600.

The present invention relates to a sputtering target containing hard nitride containing hard nitride as non-magnetic material particles. The hard nitride includes AlN, BN, Cr ₂ N, Si ₃ N ₄ , HfN, NbN, TaN, TiN, VN, and any combination thereof. The hardness (GPa) of each nitride is 12.0 for AlN, 15.4 for Cr ₂ N , 19.4 for Si ₃ N ₄ , 15.7 for HfN, 14.3 for NbN, 23.7 for TaN, 20.1 for TiN, 12.8 for VN, cubic BN It is 46.1, and the BN of hexagonal crystal is 2.0 (Fact Sheet of High Melting Point Compounds in Data Book, Handbook of Ceramic Processing: From Basics to Application Cases, Ceramic Hardness).

Cubic crystal BN and hexagonal crystal BN are known as BN used for the sputtering target, but in the present invention, cubic crystal BN having a hardness inferior to that of diamond is used. In addition, if cubic crystal BN is included, hexagonal crystal BN may also be mixed.

The non-magnetic phase includes hard nitrides with an average particle size of 1 μm or more, preferably 2 μm or more and 20 μm or less. The average particle size of the non-magnetic phase can be measured by image analysis of the EPMA surface analysis results. Image analysis by EPMA surface analysis was performed in the following procedure.

First, the sputtering surface of the sputtering target was polished, and an elemental mapping image was obtained at a magnification of 100 using an EPMA device. The obtained element map image was binarized with the "surface processing" function attached to the EPMA device. The elemental mapping image that has been binarized was analyzed with image analysis software (ImageJ 1.53e), and the average particle size of nitrides was measured. When the element constituting the nitride is one type (for example, element A) other than N (nitrogen), calculate the site where both element N and element A are detected from the element map image. When there are two or more elements other than N (nitrogen) constituting the nitride, map images of all elements other than element N are synthesized from the map images of each element, and the positions where both elements other than element N and element N are detected are calculated , Calculate the average size, and calculate the average particle size (μm) by the following formula.

[number 1] Average particle size (μm)=2×√(average size ÷ 3.14)

When the obtained average particle size is below the judging criteria of each multiple shown in Table 1, increase the magnification step by step in the order of 500, 1000, 3000, and 10000 until it becomes a value greater than the judging criteria, and repeat a series of operations to calculate the multiples The average particle size.

With the observation magnification of EPMA surface analysis, the fine non-magnetic phase cannot be observed, and the error of the average particle diameter becomes large, so the range of the average particle diameter is classified according to the observation magnification as follows. The sputtering target containing hard nitride of the present invention preferably satisfies at least one of the following (A) to (C). (A) The average particle size obtained by image analysis of the observation field of view 180 μm × 180 μm of EPMA surface analysis at a magnification of 500 is 3.6 μm to 20 μm, preferably 4 μm to 15 μm; (B) The average particle size obtained by image analysis of the observation field of view 90 μm × 90 μm of EPMA surface analysis at a magnification of 1000 is 1.8 μm to 20 μm, preferably 1.8 μm to 4 μm, more preferably 1.8 μm to 3.6 μm the following; (C) The average particle size determined by image analysis of an observation field of view of 30 μm×30 μm in EPMA surface analysis at a magnification of 3000 is 1 μm to 20 μm, preferably 1 μm to 2 μm, more preferably 1 μm to 1.8 μm.

The content of the non-magnetic phase in the sputtering target varies with the physical properties required for the deposited layer formed using the sputtering target, but generally it is preferably from 5 mol% to 50 mol%, more preferably from 5 mol% to 45 mol%. If the content of the non-magnetic phase is within the above range, the magnetic properties of the formed stacked layer can be well maintained, and the fine dispersion between the magnetic materials in the stacked layer can be exerted as a grain boundary separating adjacent magnetic materials from each other. The function of material.

The nonmagnetic phase may further contain one or more nonmagnetic materials selected from C, B ₂ O ₃ , and SiO ₂ generally used in sputtering targets. The content of the optional non-magnetic material in the sputtering target is preferably from 0 mol% to 25 mol%, more preferably from 0 mol% to 20 mol%. If the content of the arbitrarily added non-magnetic material is within the above range, the magnetic properties of the deposited layer can be well maintained, and the fine dispersion between the magnetic materials in the deposited layer can be exerted as a link between the adjacent magnetic materials. The function of the isolated grain material.

The alloy phase includes Fe or Co which is a ferromagnetic material. It may be contained as Fe alone or Co alone, or an alloy of Fe and Co, or an alloy of Fe and other elements, an alloy of Co and other elements, or an alloy of Fe, Co and other elements. Fe or Co is contained as the main component of the sputtering target. The content of Fe in the alloy phase containing Fe without Co is preferably from 35 mol% to 100 mol%, more preferably from 40 mol% to 100 mol%. When Fe is not contained but Co is contained, the Co content in the alloy phase is preferably from 50 mol% to 100 mol%, more preferably from 55 mol% to 100 mol%. When Fe or Co is contained, the total content of Fe and Co in the alloy phase is preferably from 35 mol% to 100 mol%, more preferably from 40 mol% to 100 mol%. When Fe and Co are contained, the total amount of Fe and Co in the alloy phase is preferably from 50 mol% to 100 mol%, more preferably from 60 mol% to 100 mol%, and the Fe content in the alloy phase is preferably from 30 mol% to 70 mol%. or less, more preferably not less than 35 mol% and not more than 65 mol%, and the Co content in the alloy phase is preferably not less than 20 mol% and not more than 50 mol%, more preferably not less than 25 mol% and not more than 45 mol%.

The alloy phase preferably contains Pt from 0 mol% to 60 mol%, more preferably from more than 0 mol% to 55 mol%.

The alloy phase may further contain one or more elements selected from Ag, Au, Cr, Cu, Ge, Ir, Ni, Pd, Rh, Ru, and B. The content of any added elements in the alloy phase is preferably not less than 0 mol% and not more than 30 mol%, more preferably not less than 0 mol% and not more than 25 mol%. If the content of the optional additive element in the alloy phase is within the above range, the magnetic properties of the formed deposition layer can be well maintained.

As the sputtering target of the present invention, Fe alloy-nitride, Fe alloy-C-nitride, Fe alloy-oxide-nitride, Fe alloy-C-oxide-nitride, Co alloy-nitride can be suitably exemplified. Compound, Co alloy-C-nitride, Co alloy-oxide-nitride, Co alloy-C-oxide-nitride, FePt alloy-nitride, FePt alloy-C-nitride, FePt alloy-oxide- Nitride, FePt alloy-C-oxide-nitride, CoPt alloy-nitride, CoPt alloy-C-nitride, CoPt alloy-oxide-nitride, CoPt alloy-C-oxide-nitride, FeCo alloy - Nitride, FeCo Alloy-C-Nitride, FeCo Alloy-Oxide-Nitride, FeCo Alloy-C-Oxide-Nitride, FeCoPt Alloy-Nitride, FeCoPt Alloy-C-Nitride, FeCoPt Alloy-Oxide compound-nitride, FeCoPt alloy-C-oxide-nitride. As a specific design composition, Fe-51Pt-7Si ₃ N ₄ , Fe-40Pt-20AlN, Fe-39Pt-25TaN, Fe-38Pt-15Cr ₂ N, Fe-35Pt-25VN, Fe-40Pt-20NbN, Fe-40Pt-20HfN, Fe-28Pt-30BN, Fe-35Pt-25TiN, Fe-41Pt-5Cu-5BN-8Si ₃ N ₄ , Fe-46Pt-3B ₂ O ₃ -8Si ₃ N ₄ , Fe-41Pt-4SiO ₂ -10AlN-3Si ₃ N ₄ , Fe-21Pt-21Co-10C-20AlN, Fe-30Pt-5C-30AlN, Fe-30Pt-5Ag-6C-11BN-20AlN, Fe-32Pt-6B-6Rh-20HfN, Fe -34Pt-3Ge-5C-20TiN, Co-23Pt-7Si ₃ N ₄ , Co-20Pt-19AlN, Co-19Pt-25TaN, Co-14Pt-30BN, Co-16Pt-4Cr-4SiO ₂ -15Cr ₂ N, Co -13Pt-6Ru-8Cr-16C-22VN, Co-15TiN, Fe-20TaN, Co-48Fe-20AlN.

The design composition of the sputtering target of the present invention can be repeated with the composition of the known sputtering target, but the Zr concentration when measured by metal Zr is limited to be below 1000ppm, preferably below 500ppm, more preferably below 300ppm, this point is different It is a conventional sputtering target. The Zr impurity in the sputtering target of the present invention is different from the unavoidable impurity in the composition of the conventional sputtering target, and is controlled to be below the limit value in the manufacturing process. As shown in Examples and Comparative Examples described later, even with sputtering targets having the same design composition, it was confirmed that the occurrence of particles can be significantly suppressed if the Zr concentration is limited to 1000 ppm or less.

Another feature of the sputtering target of the present invention is that the Vickers hardness Hv measured under a load of 3 kgf is 200 to 600, preferably 250 to 600. It is considered that the higher the Vickers hardness, the more particles are generated. However, if the Zr concentration is limited to 1000ppm or less, as shown in the examples and comparative examples described later, even sputtering targets with the same design composition have a Vickers hardness Hv of 200. When it is above 600 or below, it was also confirmed that the generation of particles can be significantly suppressed.

The hard nitride-containing sputtering target of the present invention can be produced by a method comprising mixing the raw material powders constituting the aforementioned alloy phase and the aforementioned non-magnetic phase for 2 hours at a rotation speed of 50 rpm to 150 rpm using a zirconia ball mill. The above time is less than 6 hours, and the mixed powder is prepared, and the aforementioned mixed powder is sintered.

In the production method of the present invention, the condition for using a zirconia ball mill to stir and mix the raw material powder is to carry out at a rotation speed of 50 rpm to 150 rpm, preferably 50 rpm to 100 rpm, more preferably 50 rpm to 75 rpm, for 2 hours to 6 hours, It is preferably not less than 3 hours and not more than 5 hours. Generally, the stirring and mixing of the zirconia ball mill is to make the mill rotate at a high speed, so that the zirconia balls collide with the raw material powder at high speed, and the raw material powder is continuously ground for a long time between the zirconia balls, thereby imparting strong mechanical energy to the raw material powder. Crushing, kneading the micronized raw material powder to form a homogeneous powder mixture. The inventors of the present invention found that when the raw material powder contains hard particles, the zirconia balls will be worn away and a small amount of zirconia is mixed as an impurity, and found the best mixing conditions to realize the homogeneous mixing of the raw material powder while suppressing the wear of the zirconia balls. In the present invention, it has been found that by suppressing the rotational speed at a low speed and relatively slow collision and shortening the stirring time, even the raw material powder containing hard nitride particles can prevent the wear of the zirconia balls and can suppress oxidation. Zirconium is mixed into the mixture of raw powders.

The raw material powder constituting the alloy phase can be metal powder or Fe-based or Co-based atomized alloy powder.

As the Fe powder, a powder having an average particle diameter D50 of 1 μm to 10 μm, preferably 2 μm to 8 μm can be used. If the average particle size is too small, there may be a risk of fire and an unavoidable increase in the concentration of impurities. If the average particle size is too large, there may be a possibility that non-magnetic material particles cannot be uniformly dispersed.

As the Co powder, a powder having an average particle diameter D50 of 1 μm to 10 μm, preferably 2 μm to 8 μm can be used. If the average particle size is too small, there may be a risk of fire and an unavoidable increase in the concentration of impurities. If the average particle size is too large, there may be a possibility that non-magnetic material particles cannot be uniformly dispersed.

As the Pt powder, a powder having an average particle diameter D50 of 0.1 μm to 10 μm, preferably 0.3 μm to 6 μm can be used. If the average particle size is too small, the impurity concentration may inevitably increase, and if the average particle size is too large, there may be a possibility that the non-magnetic material particles cannot be uniformly dispersed.

As the optional element powder, a powder having an average particle diameter D50 of 0.1 μm to 30 μm, preferably 0.5 μm to 20 μm can be used. If the average particle size is too small, the impurity concentration may inevitably increase, and if the average particle size is too large, there may be a possibility that the non-magnetic material particles cannot be uniformly dispersed.

As the Fe-based or Co-based atomized alloy powder, an atomized alloy powder having an average particle diameter D50 of 1 μm to 10 μm, preferably 2 μm to 8 μm can be used. If the average particle size is too small, the impurity concentration may inevitably increase, and if the average particle size is too large, there may be a possibility that the non-magnetic material particles cannot be uniformly dispersed.

The raw material powder constituting the non-magnetic phase includes hard nitride powder having an average particle diameter D50 of 1 μm to 40 μm, preferably 2 μm to 35 μm. As the hard nitride powder, AlN, BN, Cr ₂ N, Si ₃ N ₄ , HfN, NbN, TaN, TiN, VN and any combination thereof can be used. Cubic crystal BN is used as the BN system. When the average particle size of the hard nitride powder is within the above range, a good dispersion state can be achieved.

As the raw material powder constituting the non-magnetic phase, one or more non-magnetic materials selected from C, B ₂ O ₃ and SiO ₂ with an average particle diameter D50 of 1 μm to 10 μm, preferably 1 μm to 8 μm can be further included. . If the average particle size of the added non-magnetic material powder is within the above range, a good dispersion state can be achieved.

The sintering conditions of the mixed powder are preferably set at a sintering temperature of 800°C to 1300°C, preferably 900°C to 1250°C, and a sintering pressure of 30MPa to 120MPa, preferably 50MPa to 100MPa. [Example]

Hereinafter, the present invention will be specifically illustrated by examples and comparative examples, but the present invention is not limited thereto. The methods for measuring the Zr concentration, Vickers hardness, average particle size, relative density and particle number of the hard nitride non-magnetic phase of the sputtering targets of the following examples and comparative examples are as follows.

[Zr concentration] Cut out a test piece with a diameter of 30 mm from the sputtering target, use #80, #320 and #1200 SiC abrasive paper to grind the horizontal surface of the sputtering target relative to the sputtering surface, and use the fluorescent X-ray of the Rh X-ray tube The X-ray analyzer (ZSX PrimusIV, RIGAKU Co., Ltd.) measured the Zr concentration by inputting the conditions in Table 2 to the EZ scan.

[Vickers Hardness] Measured in accordance with JIS Z 2244. Specifically, after polishing the horizontal plane of the sputtering target relative to the sputtering surface using #80, #320, and #1200 SiC abrasive paper, use diamond abrasive grains with a particle size of 1 μm for polishing and grinding, and use a Vickers hardness tester (HV-115, Mitsui Co., Ltd.), observe the size of the depression when a test load of 3.00kgf is applied to a diamond indenter with a regular square pyramid with an opposite angle of 136° with a microscope, measure the length of the straight line connecting the diagonals, and calculate the surface area of the depression (mm ² ), calculate the test load (kgf)/depression surface area (mm ² ).

[Average particle size of hard nitride non-magnetic phase] After using #80, #320 and #1200 SiC abrasive paper to grind the vertical surface of the sputtering target relative to the sputtering surface, use a diamond atomizer with a particle size of 1 μm for polishing and polishing, and use the EPMA shown in Table 3 and Table 4 As for analysis conditions, an elemental mapping image was obtained using an EPMA apparatus (JXA-8500F, JEOL Ltd.).

The obtained elemental mapping image was binarized with the "surface processing" function attached to the EPMA device (JXA-8500F). Specifically, select a binarized image by expressing the element map image with the maximum number of maps 9, and confirm the upper limit and lower limit values on the "level change" screen. Select "Subtract Constant" on the "Mapping Calculation" screen, and input the confirmed lower limit value into K on the "Level Change" screen to execute. Select "Divide by Constant" again on the "Mapping Calculation" screen, and input the value obtained by subtracting the lower limit value from the upper limit value confirmed on the "Level Change" screen into K for execution. Execute by changing the "Display Mode" selection screen to the contents in Table 5. Change the "level change" screen to the content in Table 6 and execute it.

Save a screenshot of the element map image that has been binarized above in PNG format. The elemental mapping images in PNG format were analyzed by image analysis software (ImageJ 1.53e), and the average particle size of nitrides was determined. Specifically, the average particle diameter of nitrides was measured by the following procedure. Open the element map image in PNG format with image analysis software (ImageJ 1.53e). When the nitride is composed of element A and N (nitrogen), the mapped image area of element A and element N is copied with 286×286 pixels and stored as a new image. The contents of Table 7 were input into the image computer of the image analysis software (ImageJ 1.53e) and executed to create a file in which the positions where both element A and element N were detected were calculated.

When there are two or more elements constituting the nitride other than N (nitrogen), the mapped image area of each element is copied with 286×286 pixels and saved as a new image, and the operation in Table 7 is set to "or( OR)", in Image 1 and Image 2, select the mapped images other than the element N that constitutes the nitride, and use an image computer to synthesize all the mapped images other than the element N that constitutes the nitride. In addition to selecting this image as image 1 of the image computer in Table 7, input the content of the image computer in Table 7 and execute it to create a program that will detect both elements other than N and element N that constitute nitrides. The file after the position is calculated.

The obtained file is converted and reversed in black and white, and the content in Table 8 is entered in the setting specification (Set Scale) to execute. Also, input the field of view of each multiple in the known distance. That is, input 900 for 100 times, 180 for 500 times, 90 for 1000 times, 30 for 3000 times, and 10 for 10000 times.

Enter the contents of Table 9 in the analysis of particles and execute. In addition, according to the observation magnification, the value in Table 10 was input in correspondence with the observation magnification in the size (μm ² ).

Using the average size of the summary screen displayed after the analysis, the average particle diameter (μm) was calculated by the following formula.

[number 2] Average particle size (μm) = 2 × √ (average size ÷ 3.14)

First, execute the above series of analysis in the image of 100 times. When the obtained average particle size is below the judgment standard of each magnification shown in Table 11, it will increase step by step in the order of 500 times, 1000 times, 3000 times and 10000 times. , until it becomes a value greater than the judgment criterion.

[Relative Density] Measured by the Archimedes method using pure water as a replacement fluid. The mass of the sintered body was measured, and the buoyancy (=volume of the sintered body) was measured with the sintered body floating in the replacement fluid. The measured density (g/cm ³ ) was obtained by dividing the mass (g) of the sintered body by the volume (cm ³ ) of the sintered body. The relative density was set based on the ratio of the composition of the sintered body to the calculated theoretical density (measured density/theoretical density).

[number of particles] The sintered body was processed to a diameter of 153 mm and a thickness of 2 mm, and bonded to a Cu backing plate with a diameter of 161 mm and a thickness of 4 mm with indium to obtain a sputtering target. This sputtering target was installed in a magnetron sputtering device, and after sputtering for 40 seconds in an Ar gas atmosphere with an output of 500 W and a gas pressure of 1 Pa, the number of particles attached to the substrate was measured with a particle counter.

[Examples 1-26 and Comparative Examples 1-15] Sputtering targets with the design compositions shown in Table 12 and Table 13 were manufactured, and the Zr concentration, Vickers hardness, average particle size and relative density of the hard nitride nonmagnetic phase were measured and the number of particles. In the design composition of Table 12 and Table 13, since Fe or Co constitutes the rest, the content is omitted. For example, Fe-51Pt-7Si ₃ N ₄ in Example 1 represents 42Fe-51Pt-7Si ₃ N ₄ .

As raw material powders of the alloy phase, Fe powder with an average particle diameter D50 of 7 μm, Co powder with an average particle diameter D50 of 3 μm, and Pt powder with an average particle diameter D50 of 1 μm were used. As additional elements for the alloy phase, Cu powder with an average particle diameter D50 of 5 μm, Ag powder with an average particle diameter D50 of 4 μm, B powder with an average particle diameter D50 of 8 μm, Ge powder with an average particle diameter D50 of 10 μm, and Cr powder having a diameter D50 of 15 μm, Ru powder having an average particle diameter D50 of 13 μm, and Rh powder having an average particle diameter D50 of 13 μm.

As the hard nitride powder, Si ₃ N ₄ powder with an average particle size D50 of 20 μm, AlN powder with an average particle size D50 of 8 μm, TaN powder with an average particle size D50 of 4 μm, and Cr with an average particle size D50 of 7 μm can be used. ₂ N powder, NbN powder with an average particle size D50 of 10 μm, HfN powder with an average particle size D50 of 35 μm, cubic BN powder (cBN) with an average particle size D50 of 3 μm, TiN powder with an average particle size D50 of 9 μm, average VN powder with a particle size D50 of 7 μm.

As the additional non-magnetic material powder, hexagonal BN powder (BN) with an average particle diameter D50 of 5 μm, _B2O3 powder with an average particle diameter D50 of 5 μm, C powder with an average particle diameter D50 of 5 μm _, average particle diameter D50 is 1μm SiO ₂ powder.

In Examples 1 to 26, each raw material powder weighed so as to have the design composition shown in Table 12 was put into a stirring mill together with 4 kg of zirconia balls, and the mixed powder was obtained by stirring and mixing at a rotation speed of 100 rpm for 4 hours. Sintering was carried out at the sintering temperature shown in Table 12 with a sintering pressure of 66 MPa. Empty column in Table 12 means not added.

Regarding Comparative Examples 1 to 15, each raw material powder weighed so as to have the design composition shown in Table 13 was put into a stirring mill together with 4 kg of zirconia balls, and stirred and mixed under the stirring conditions shown in Table 13. The mixed powder was sintered at the sintering temperature shown in Table 13 at a sintering pressure of 66 MPa. Empty column in Table 13 means not added.

After the relative density of the obtained sintered body was measured, it was processed into a sputtering target, and the Zr concentration, the average particle size of the hard nitride, the Vickers hardness and the number of particles were measured. The results are shown in Tables 14 and 15. The relationship between the Zr concentration and the number of particles is shown in FIG. 1 , and the relationship between the Vickers hardness and the number of particles is shown in FIG. 2 .

From Tables 14 to 15 and Figure 1, it can be seen that when the Zr concentration is above 2000ppm, the number of particles is more than 2000, but when the Zr concentration is below 1000ppm, the number of particles is reduced, especially when the Zr concentration is below 300ppm, the number of particles is small and does not reach 400. Moreover, from Tables 14 to 15 and Figure 2, it can be seen that when the Vickers hardness Hv is 600 or more, the number of particles is more than 2000, but the number of particles is less than 400 when the Vickers hardness Hv is in the range of 200 to 600.

Though the mensuration of the average particle diameter of the hard nitride particle of the sputtering target of embodiment 1～26 can be carried out under magnification 500～3000, but the average particle diameter of the hard nitride particle of the sputtering target of comparative example 1～15 is The assay must be increased by a factor of 10,000. From Tables 14 and 15, it can be seen that the average particle size of the hard nitrides in Examples 1-26 falls within the range of 1.3 μm to 12.8 μm, and the average particle size of the hard nitrides in Comparative Examples 1-15 is fine in the range of 0.3-0.9 μm. particle.

Fig. 3 is the SEM observation photograph (magnification 1000) of the structure of the sputtering target of embodiment 1, Fig. 4 is the SEM observation photograph (magnification 1000) of the structure of the sputtering target of embodiment 2, Fig. 5 is the sputtering of comparative example 2 SEM observation photo of the plated target structure (magnification 1000). By EPMA analysis, in the figure, it is confirmed that the black particles are hard nitride particles, and the white to gray are alloy phases. Comparing Fig. 3 and Fig. 5, it can be seen that the white alloy phase and black particles of Comparative Example 2 (Fig. 5) are more finely dispersed than those of Example 1 (Fig. 3). It can be seen from Figure 4 that relatively large hard nitride particles are homogeneously dispersed with the alloy phase.

From Tables 14 to 15 and Figures 3 to 5, it can be seen that compared with the sputtering target of the comparative example produced by the conventional method, the sputtering target produced by the production method of the present invention has relatively large hard nitride particles, but the nonmagnetic phase It is homogeneously dispersed with the alloy phase.

[ Fig. 1 ] is a graph showing the relationship between the Zr concentration and the number of particles in the sputtering targets of Examples and Comparative Examples. [ Fig. 2 ] is a graph showing the relationship between the Vickers hardness and the number of particles in the sputtering targets of Examples and Comparative Examples. [ Fig. 3 ] is a SEM observation photograph (magnification: 1000) of the structure of the sputtering target of Example 1. [FIG. 4] It is the SEM observation photograph (magnification 1000) of the structure of the sputtering target of Example 2. [ Fig. 5 ] is a SEM observation photograph (magnification: 1000) of the structure of the sputtering target of Comparative Example 2.

Claims (10)

A sputtering target containing hard nitride, characterized by an alloy phase comprising Fe or Co, and comprising AlN, BN, Cr ₂ N, Si ₃ N ₄ , HfN, NbN, TaN, TiN, VN and the It is made of the non-magnetic phase of hard nitride in any combination of metal Zr, the Zr impurity concentration is limited to 1000ppm or less, and the Vickers (Vickers) hardness Hv measured under the load condition of 3kgf is 200 to 600 . The sputtering target containing hard nitride as claimed in claim 1, wherein the Zr impurity concentration is limited below 500ppm. The sputtering target containing hard nitride as claimed in claim 1 or 2, wherein the aforementioned non-magnetic phase satisfies at least one of the following: The average particle size obtained by image analysis of the observation field of view 180 μm × 180 μm of EPMA surface analysis at a magnification of 500 is 4 μm to 20 μm; The average particle size obtained by image analysis of the observation field of view of EPMA surface analysis at a magnification of 1000 of 90 μm × 90 μm is not less than 2 μm and not more than 20 μm; and The average particle size obtained by image analysis of the observation field of view 30 μm×30 μm of EPMA surface analysis at a magnification of 3000 is 1 μm to 20 μm. The sputtering target containing hard nitride according to Claim 1 or 2, wherein the content of the aforementioned non-magnetic phase in the aforementioned sputtering target is not less than 5 mol% and not more than 50 mol%. The sputtering target containing hard nitride according to claim 1 or 2, wherein the non-magnetic phase further comprises one or more selected from C, B ₂ O ₃ and SiO ₂ . The sputtering target containing hard nitride as claimed in claim 1 or 2, wherein the alloy phase contains Pt at 0 mol% or more and 60 mol% or less. The sputtering target containing hard nitride according to claim 1 or 2, wherein the alloy phase further comprises one or more selected from Ag, Au, Cr, Cu, Ge, Ir, Ni, Pd, Rh, Ru and B Elements. A method for manufacturing a sputtering target containing hard nitride, the sputtering target containing hard nitride is characterized by an alloy phase containing Fe or Co, and containing selected from AlN, BN, Cr ₂ N, Si ₃ N ₄ , HfN, NbN, TaN, TiN, VN, and the non-magnetic phase of hard nitride in any combination of these, the Zr impurity concentration when measured by metal Zr is limited to 1000ppm or less, and the dimension measured under the load condition of 3kgf The hardness Hv is 200 to 600, and the method is characterized by mixing the raw material powders constituting the aforementioned alloy phase and the aforementioned nonmagnetic phase for 2 hours to 6 hours using a zirconia ball mill at a rotation speed of 50 rpm to 150 rpm. The powders are mixed, and the mixed powders are sintered. The method for manufacturing a sputtering target containing hard nitride as claimed in claim 8, wherein the raw material powders constituting the alloy phase are metal powders of each raw material or Fe-based or Co-based atomized alloy powders. The production method according to claim 8 or 9, wherein the raw material powder constituting the non-magnetic phase includes hard nitride powder having an average particle diameter D50 of 1 μm or more and 40 μm or less.

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