JP5024660B2 - Method for producing Co-based sintered alloy sputtering target for forming magnetic recording film with less generation of particles - Google Patents

Description

  The present invention relates to a method of manufacturing a sputtering target for forming a magnetic recording film applied to a high-density magnetic recording medium of a hard disk, particularly a magnetic recording film applied to a perpendicular magnetic recording medium.

Hard disk devices are generally used as external recording devices such as computers and digital home appliances, and further improvement in recording density is required. Therefore, in recent years, a perpendicular magnetic recording system that can realize ultra-high-density recording has attracted attention. Unlike the conventional in-plane recording system, this perpendicular magnetic recording system is said to have a stable recording magnetization as the density is increased in principle, and its practical use has started. A CoCrPt—SiO ₂ granular magnetic recording film has been proposed as a promising candidate for a material to be applied to the magnetic recording layer of this perpendicular magnetic recording type hard disk medium, and this magnetic recording film is a high-performance magnetic recording film. is necessary. As one of the magnetic recording films applicable to this, a CoCrPt—SiO ₂ granular magnetic recording film has been proposed. This CoCrPt—SiO ₂ granular magnetic recording film has a Co-based sintered alloy phase containing Cr and Pt and silicon dioxide. It is known to produce by a magnetron sputtering method using a Co-based sintered alloy sputtering target having a mixed phase (see Non-Patent Document 1).
This Co-based sintered alloy sputtering target usually comprises silicon dioxide powder, Cr powder, Pt powder and Co powder, silicon dioxide: 2 to 15 mol%, Cr: 3 to 20 mol%, Pt: 5 to 30 mol%. It is known that the remainder is prepared by mixing and mixing so as to be a composition consisting of Co, and then pressure sintering by a method such as hot pressing or hot isostatic pressing, Generation of particles is reduced by using silicon dioxide powder produced by a high-temperature flame hydrolysis method as silicon dioxide powder, and making the silicon dioxide phase dispersed in the target substrate a very fine structure of 10 μm or less ( (See Patent Document 1, Patent Document 2, etc.).
Further, in addition to the SiO ₂ , nonmagnetic materials such as TiO, Cr ₂ O ₃ , TiO ₂ , Ta ₂ O ₅ , Al ₂ O ₃ , BeO ₂ , MgO, ThO ₂ , ZrO ₂ , CeO ₂ , and Y ₂ O _3. It is known that oxides can be used (see Patent Documents 3 and 4).
“Fuji Times” Vol. 75No. 3 2002 (pages 169-172) Japanese Patent Laid-Open No. 2001-236643 JP 2004-339586 A JP 2003-36525 A JP 2006-24346 A

  However, the Co-based sintered alloy sputtering target produced by the conventional method inevitably generates particles, and a sputtering target made of a Co-based sintered alloy with less generation of particles has been demanded.

Therefore, the present inventor conducted research to obtain a Co-based sintered alloy sputtering target with less particle generation,
(A) Aggregates or precipitates (hereinafter referred to as chromium) whose main components are coarse Cr and O whose absolute maximum length (maximum value of the distance between any two points on the particle outline) exceeds 10 μm in the target substrate. That the dispersion of oxide aggregates) contributes to particle generation,
(B) In order to prevent the coarse chromium oxide aggregates from being present in the substrate, the raw material powder contains Cr: 50 to 70 atomic% instead of Cr powder, with the balance being Co. The inventors have obtained knowledge that it is preferable to use an alloy powder mainly composed of an intermetallic compound of Cr and Co having a composition (hereinafter referred to as a Cr—Co alloy powder).

This invention has been made based on such knowledge,
(1) Cr—Co alloy powder, Pt powder, nonmagnetic oxide powder, and Co powder having a component composition containing Cr: 50 to 70 atomic% and the balance being Co are prepared as raw material powder. Nonmagnetic oxide: 2 to 15 mol%, Cr: 3 to 20 mol%, Pt: 5 to 30 mol%, balance: component composition consisting of Co, mixed and mixed, then pressed A method for producing a Co-based sintered alloy sputtering target for forming a magnetic recording film with less generation of particles to be sintered,
(2) The particle according to (1), wherein the nonmagnetic oxide is any one of silicon dioxide, tantalum oxide, titanium oxide, aluminum oxide, magnesium oxide, thorium oxide, zirconium oxide, cerium oxide, and yttrium oxide. A method for producing a Co-based sintered alloy sputtering target for forming a magnetic recording film with less generation,
(3) The pressure sintering is characterized by the method for producing a Co-based sintered alloy sputtering target for forming a magnetic recording film with less particle generation according to (1), which is hot pressing or hot isostatic pressing. Is.

  The reason why the component composition of the Cr—Co alloy powder used in the method for producing a Co-based sintered alloy sputtering target for forming a magnetic recording film with less particle generation according to the present invention is limited as described above is that Cr is less than 50 atomic% or 70 When the content exceeds atomic%, the ratio of the solid solution Co or solid solution Cr in which the bond between Co and Cr is weak in addition to the intermetallic compound in the powder increases, and Cr is mixed with oxygen or nonmagnetic oxidation during mixing or sintering. This is because it tends to react with the product to form coarse chromium oxide aggregates, which is not preferable. A more preferable range of Cr contained in the Cr—Co alloy powder is 54 to 67 atomic%.

The reason why chromium oxide aggregates cause particle generation is that chromium oxide aggregates are very fragile, fall off during spattering, cause abnormal discharge, and when the size of chromium oxide aggregates is large. This is because it falls off from the target surface during processing of the target, and a defect is formed in the dropped part. The reason why the formation of chromium oxide aggregates is suppressed by using the Cr—Co alloy powder as a raw material powder is that an intermetallic compound phase exists between Cr and Co in the vicinity of 54 to 67 atomic% of Cr. However, when Co and Cr are alloyed with a composition in the vicinity and all or most of Cr is introduced in the form of an intermetallic compound with Co, the Cr in the intermetallic compound is in a state of being firmly bonded to Co. It is thought that this is because the reaction with oxygen and non-magnetic oxides is less likely to occur than when it exists as a simple substance or a solid solution.

Next, the particle size of the Cr—Co alloy powder used in the method for producing a Co-based sintered alloy sputtering target for forming a magnetic recording film with less particle generation according to the present invention is 50% larger than 150 μm. Since the pulverization does not proceed sufficiently, it is preferable that the particle size of the Cr—Co alloy powder is 50% particle size of 150 μm or less. It is more preferable that the 50% particle size be 45 μm or less. Further, both Co powder and Pt powder have 50% particle size of 50 μm or less (more preferably, 50% particle size is 40 μm or less), and nonmagnetic oxide powder has 50% particle size of 20 μm or less (more preferably 50% particle size). The diameter is preferably 10 μm or less. The reason is that if the Co powder and the Pt powder are larger than this, it is difficult to obtain a uniform structure after mixing. Further, when the particle size of the nonmagnetic oxide powder is larger than this, a large nonmagnetic oxide of 10 μm or more is likely to be present in the target even after the mixing and pulverization process, which causes abnormal discharge and particle generation during sputtering. Because it becomes.
The raw material powder is preferably mixed in an inert gas atmosphere. This is because it further prevents Cr from being combined with oxygen to form chromium oxide aggregates during mixing.

  The present invention can provide a sputtering target capable of forming an excellent magnetic recording film with less generation of particles, and can greatly contribute to the development of industries such as computers and digital home appliances.

As raw material powders, Co—Cr alloy powders A to J having the component compositions shown in Table 1 were prepared by a gas atomization method. Since the Co-Cr alloy powders A to J obtained by the gas atomization method had a 50% particle size of 95 μm, the Co—Cr alloy powders A to J were classified by a sieve having an opening of 45 μm, and laser diffraction was performed. The 50% particle size measured by the method was all classified to 35 μm. Further, commercially available 50% particle size: 10 μm Co powder, 50% particle size: 15 μm Pt powder, 50% particle size: 3 μm SiO ₂ powder, 50% particle size: 3 μm TiO ₂ powder, 50% particle size : 3 μm Ta ₂ O ₅ powder and 50% particle size: 10 μm Cr powder were prepared.

Example 1
These raw material powders were blended so as to have the blending composition shown in Table 2, and the obtained blended powder was put into a 10 liter container together with zirconia balls as a grinding medium, and the atmosphere in the container was placed in an Ar gas atmosphere. After replacement, the container was sealed. This container was rotated with a ball mill for 16 hours to produce a mixed powder.
The obtained mixed powder is filled into a vacuum hot press apparatus, and hot press having the component composition shown in Table 2 by vacuum hot pressing in a vacuum atmosphere under conditions of temperature: 1200 ° C., pressure: 15 MPa, and 3 hours. The present invention methods 1-8, comparative methods 1-2, and conventional method 1 are prepared by cutting the hot press body to produce a target having dimensions of diameter: 152.4 mm and thickness: 3 mm. Carried out.

The absolute maximum length of the chromium oxide aggregates dispersed in the substrate of the target prepared by the above-described inventive methods 1 to 8, comparative methods 1 and 2 and conventional method 1 (maximum of the distance between any two points on the particle contour) Value) was measured by EPMA, and the presence or absence of coarse chromium oxide aggregates having an absolute maximum length exceeding 10 μm was shown in Table 2.
The absolute maximum length of the chromium oxide aggregates by EPMA was measured as follows. A sample was cut out from the hot press body produced by the present invention methods 1 to 8, comparative methods 1 and 2, and conventional method 1, the cross section was filled in resin, and mirror-polished. This cross-sectional structure was subjected to surface analysis at 1000 times magnification under the conditions of acceleration voltage: 15 kV, irradiation current: 5 × 10 ⁻⁸ A by field emission EPMA (JXA-8500F manufactured by JEOL Ltd.), and Cr element A mapping image was obtained. The element mapping image of Cr was an image with contrast and color tone so that the Cr-enriched region (that is, the chromium oxide aggregate) could be clearly discriminated. The obtained Cr element mapping image is saved as an image file in bitmap format without degrading the image quality, and this image is separately read into a personal computer image processing software (Mitani Corp., Win Roof) and binarized, The absolute maximum length of the region enriched with Cr from the matrix was measured by image processing. In binarization, a threshold value was selected so that the size of the Cr-enriched area did not change from the original image. For the calibration of the length at the time of measurement, a scale bar displayed on the element mapping image of Cr by the original EPMA was used.

Further, after degreasing the targets obtained in the above-mentioned inventive methods 1 to 8, comparative methods 1 and 2 and conventional method 1 with an organic solvent, and then vacuum-drying at 150 ° C. for 8 hours in a vacuum, a copper backing Join the plate and attach it to a commercially available sputtering device.
Ultimate vacuum: 5 × 10 ⁻⁵ Pa,
Power: DC 800W,
Ar gas pressure: 6.0 Pa,
Target substrate distance: 60mm,
Substrate heating: None,
Pre-sputtering was performed under the conditions described above, and after the target surface processed layer was removed, the chamber was once opened to the atmosphere, and chamber members such as a deposition prevention plate were cleaned. Thereafter, vacuuming is performed again until the degree of vacuum is reached, and after vacuuming, pre-sputtering is performed for 30 minutes to remove the air adsorbing components and the metal oxide layer on the target surface. S: A magnetic recording film of 100 nm was formed. Under the same conditions, a magnetic recording film having a thickness of 100 nm is formed on a total of 25 4-inch Si wafers, and the number of particles of 1.0 μm or more adhering to the wafer surface by a commercially available foreign substance inspection apparatus for the formed wafers. The average value of 25 sheets was calculated, and the result is shown in Table 2.

From the results shown in Table 2, it was prepared by the present invention methods 1 to 8 which were prepared by blending Co: Cr alloy powders A to H containing Cr: 50 to 70 atomic% and the balance consisting of Co as raw material powders. The target was 50% particle size: 10 μm Co powder, 50% particle size: 10 μm Cr powder, 50% particle size: 15 μm Pt powder and 50% particle size: 3 μm without adding Co—Cr alloy powder. It can be seen that the generation of particles is less than that of the target prepared by the conventional method 1 prepared by mixing and mixing the SiO ₂ powder. However, since the target produced by Comparative Methods 1 and 2 produced using Co-Cr alloy powders I to J having a component composition outside the scope of the present invention, the Co-Cr alloy powder generates more particles. It turns out that it is not preferable.

Example 2
The raw material powder prepared previously is blended so as to have the blending composition shown in Table 3, and the obtained blended powder is put into a 10 liter container together with zirconia balls as a grinding medium, and the atmosphere in the container is filled with Ar gas. The atmosphere was replaced, and then the container was sealed. This container was rotated with a ball mill for 16 hours to produce a mixed powder.
The obtained mixed powder was filled in a SUS container and subjected to vacuum degassing treatment held at 550 ° C. for 12 hours, and then the SUS container was sealed and the mixed powder was vacuum sealed. The SUS container filled with this mixed powder is subjected to hot isostatic pressing under conditions of temperature: 1200 ° C., pressure: 100 MPa, 3 hours, and then the SUS container is opened to have the component composition shown in Table 3. A hot isostatic press body was prepared, and the hot isostatic press body was cut to produce a target having dimensions of diameter: 152.4 mm and thickness: 3 mm. Methods 3-4 and Conventional Method 2 were performed.

The absolute maximum length of the chromium oxide aggregates dispersed in the substrate of the target produced by the above-mentioned inventive methods 9 to 16, comparative methods 3 to 4 and conventional method 2 (maximum of the distance between any two points on the particle outline) Value) was measured by EPMA, and the presence or absence of coarse chromium oxide aggregates having an absolute maximum length exceeding 10 μm was shown in Table 3.
The absolute maximum length of the chromium oxide aggregates by EPMA was measured as follows. A sample was cut out from the targets prepared in the present invention methods 9 to 16, comparative methods 3 to 4, and the conventional method 2, the cross section was filled in resin, and mirror polished. This cross-sectional structure was subjected to surface analysis at 1000 times magnification under the conditions of acceleration voltage: 15 kV, irradiation current: 5 × 10 ⁻⁸ A by field emission EPMA (JXA-8500F manufactured by JEOL Ltd.), and Cr element A mapping image was obtained. The element mapping image of Cr was an image with contrast and color tone so that the Cr-enriched region (that is, the chromium oxide aggregate) could be clearly discriminated. The obtained Cr element mapping image is saved as an image file in bitmap format without degrading the image quality, and this image is separately read into a personal computer image processing software (Mitani Corp., Win Roof) and binarized, The absolute maximum length of the region enriched with Cr from the matrix was measured by image processing. In binarization, a threshold value was selected so that the size of the Cr-enriched area did not change from the original image. For the calibration of the length at the time of measurement, a scale bar displayed on the element mapping image of Cr by the original EPMA was used.

Further, after degreasing the targets obtained by the above-mentioned inventive methods 9 to 16, comparative methods 3 to 4 and conventional method 2 with an organic solvent, followed by vacuum drying at 150 ° C. for 8 hours in a vacuum, a copper backing Join the plate and attach it to a commercially available sputtering device.
Ultimate vacuum: 5 × 10 ⁻⁵ Pa,
Power: DC 800W,
Ar gas pressure: 6.0 Pa,
Target substrate distance: 60mm,
Substrate heating: None,
Pre-sputtering was performed under the conditions described above, and after the target surface processed layer was removed, the chamber was once opened to the atmosphere, and chamber members such as a deposition prevention plate were cleaned. Thereafter, vacuuming is performed again until the degree of vacuum is reached, and after vacuuming, pre-sputtering is performed for 30 minutes to remove the air adsorbing components and the metal oxide layer on the target surface. S: A magnetic recording film of 100 nm was formed. Under the same conditions, a magnetic recording film having a thickness of 100 nm is formed on a total of 25 4-inch Si wafers, and the number of particles of 1.0 μm or more adhering to the wafer surface by a commercially available foreign substance inspection apparatus for the formed wafers. The average value of 25 sheets was calculated, and the results are shown in Table 3.

From the results shown in Table 3, it was prepared by the present invention methods 9 to 16 which were prepared by blending Co: Cr alloy powders A to H containing Cr: 50 to 70 atomic% and the balance being Co, as raw material powders. The target was 50% particle size: 10 μm Co powder, 50% particle size: 10 μm Cr powder, 50% particle size: 15 μm Pt powder and 50% particle size: 3 μm without adding Co—Cr alloy powder. It can be seen that the generation of particles is less than that of the target prepared by the conventional method 2 prepared by mixing and mixing the SiO ₂ powder. However, since the Co-Cr alloy powder produced using the Co-Cr alloy powders I to J having a component composition outside the scope of the present invention produced the comparative methods 3 to 4, the generation of particles increases. It turns out that it is not preferable.

Example 3
The raw material powder prepared previously is blended so as to have the blending composition shown in Table 4, and the obtained blended powder is put into a 10 liter container together with zirconia balls as a grinding medium, and the atmosphere in the container is filled with Ar gas. The atmosphere was replaced, and then the container was sealed. This container was rotated with a ball mill for 16 hours to produce a mixed powder.
The obtained mixed powder is filled in a vacuum hot press apparatus, and hot press having the component composition shown in Table 4 by vacuum hot pressing in a vacuum atmosphere under conditions of temperature: 1200 ° C., pressure: 15 MPa, and 3 hours. The hot-pressed body is cut to produce a target having the dimensions of diameter: 152.4 mm and thickness: 3 mm, whereby the present invention methods 17 to 24, comparative methods 5 to 6 and conventional method 3 are prepared. Carried out.

The absolute maximum length of the chromium oxide aggregates dispersed in the substrate of the target produced by the above-mentioned inventive methods 17 to 24, comparative methods 5 to 6 and conventional method 3 (maximum of the distance between any two points on the particle outline) Value) was measured by EPMA, and the presence or absence of coarse chromium oxide aggregates having an absolute maximum length exceeding 10 μm was shown in Table 4.
The absolute maximum length of the chromium oxide aggregates by EPMA was measured as follows. Samples were cut out from the targets prepared in the present invention methods 17 to 24, comparative methods 5 to 6, and conventional method 3, the cross section was filled in resin, and mirror polished. This cross-sectional structure was subjected to surface analysis at 1000 times magnification under the conditions of acceleration voltage: 15 kV, irradiation current: 5 × 10 ⁻⁸ A by field emission EPMA (JXA-8500F manufactured by JEOL Ltd.), and Cr element A mapping image was obtained. The element mapping image of Cr was an image with contrast and color tone so that the Cr-enriched region (that is, the chromium oxide aggregate) could be clearly discriminated. The obtained Cr element mapping image is saved as an image file in bitmap format without degrading the image quality, and this image is separately read into a personal computer image processing software (Mitani Corp., Win Roof) and binarized, The absolute maximum length of the region enriched with Cr from the matrix was measured by image processing. In binarization, a threshold value was selected so that the size of the Cr-enriched area did not change from the original image. For the calibration of the length at the time of measurement, a scale bar displayed on the element mapping image of Cr by the original EPMA was used.

Further, after degreasing the targets obtained in the above-mentioned inventive methods 17 to 24, comparative methods 5 to 6 and conventional method 3 with an organic solvent, followed by vacuum drying at 150 ° C. for 8 hours in a vacuum, a copper backing Join the plate and attach it to a commercially available sputtering device.
Ultimate vacuum: 5 × 10 ⁻⁵ Pa,
Power: DC 800W,
Ar gas pressure: 6.0 Pa,
Target substrate distance: 60mm,
Substrate heating: None,
Pre-sputtering was performed under the conditions described above, and after the target surface processed layer was removed, the chamber was once opened to the atmosphere, and chamber members such as a deposition prevention plate were cleaned. Thereafter, vacuuming is performed again until the degree of vacuum is reached, and after vacuuming, pre-sputtering is performed for 30 minutes to remove the air adsorbing components and the metal oxide layer on the target surface. S: A magnetic recording film of 100 nm was formed. Under the same conditions, a magnetic recording film having a thickness of 100 nm is formed on a total of 25 4-inch Si wafers, and the number of particles of 1.0 μm or more adhering to the wafer surface by a commercially available foreign substance inspection apparatus for the formed wafers. The average value of 25 sheets was calculated, and the result is shown in Table 4.

From the results shown in Table 4, Cr: 50 to 70 atomic% was produced by the present invention methods 17 to 24, which were prepared by blending Co—Cr alloy powders A to H containing Co as the raw material powder. The target was 50% particle size: 10 μm Co powder, 50% particle size: 10 μm Cr powder, 50% particle size: 15 μm Pt powder and 50% particle size: 3 μm without adding Co—Cr alloy powder. It can be seen that the generation of particles is less than that of the target prepared by the conventional method 3 prepared by mixing and mixing TiO ₂ powder. However, since the Co-Cr alloy powder produced using Comparative Methods 5 to 6 using Co-Cr alloy powders I to J having a component composition outside the scope of the present invention, the generation of particles increases. It turns out that it is not preferable.

Example 4
The raw material powder prepared previously is blended so as to have the blending composition shown in Table 5, and the obtained blended powder is put into a 10-liter container together with zirconia balls as a grinding medium, and the atmosphere in the container is filled with Ar gas. The atmosphere was replaced, and then the container was sealed. This container was rotated with a ball mill for 16 hours to produce a mixed powder.
The obtained mixed powder was filled in a SUS container and subjected to vacuum degassing treatment held at 550 ° C. for 12 hours, and then the SUS container was sealed and the mixed powder was vacuum sealed. The SUS container filled with this mixed powder was subjected to hot isostatic pressing under conditions of temperature: 1200 ° C., pressure: 100 MPa, 3 hours, and then the SUS container was opened to have the component composition shown in Table 5. A hot isostatic press body is prepared, and the hot isostatic press body is cut to produce a target having a diameter of 152.4 mm and a thickness of 3 mm. Methods 7-8 and Conventional Method 4 were performed.

The absolute maximum length of the chromium oxide aggregates dispersed in the substrate of the target prepared by the above-described inventive methods 25-32, comparative methods 7-8 and conventional method 4 (maximum of the distance between any two points on the particle contour) Value) was measured by EPMA, and the presence or absence of coarse chromium oxide aggregates having an absolute maximum length exceeding 10 μm was shown in Table 5.
The absolute maximum length of the chromium oxide aggregates by EPMA was measured as follows. A sample was cut out from the targets prepared in the present invention methods 25 to 32, comparative methods 7 to 8 and conventional method 4, the cross section was filled in resin, and mirror polished. This cross-sectional structure was subjected to surface analysis at 1000 times magnification under the conditions of acceleration voltage: 15 kV, irradiation current: 5 × 10 ⁻⁸ A by field emission EPMA (JXA-8500F manufactured by JEOL Ltd.), and Cr element A mapping image was obtained. The element mapping image of Cr was an image with contrast and color tone so that the Cr-enriched region (that is, the chromium oxide aggregate) could be clearly discriminated. The obtained Cr element mapping image is saved as an image file in bitmap format without degrading the image quality, and this image is separately read into a personal computer image processing software (Mitani Corp., Win Roof) and binarized, The absolute maximum length of the region enriched with Cr from the matrix was measured by image processing. In binarization, a threshold value was selected so that the size of the Cr-enriched area did not change from the original image. For the calibration of the length at the time of measurement, a scale bar displayed on the element mapping image of Cr by the original EPMA was used.

Furthermore, after degreasing the targets obtained by the above-mentioned inventive methods 25-32, comparative methods 7-8, and conventional method 4 with an organic solvent, and then vacuum-drying at 150 ° C. for 8 hours in a vacuum, a copper backing Join the plate and attach it to a commercially available sputtering device.
Ultimate vacuum: 5 × 10 ⁻⁵ Pa,
Power: DC 800W,
Ar gas pressure: 6.0 Pa,
Target substrate distance: 60mm,
Substrate heating: None,
Pre-sputtering was performed under the conditions described above, and after the target surface processed layer was removed, the chamber was once opened to the atmosphere, and chamber members such as a deposition prevention plate were cleaned. Thereafter, vacuuming is performed again until the degree of vacuum is reached, and after vacuuming, pre-sputtering is performed for 30 minutes to remove the air adsorbing components and the metal oxide layer on the target surface. S: A magnetic recording film of 100 nm was formed. Under the same conditions, a magnetic recording film having a thickness of 100 nm is formed on a total of 25 4-inch Si wafers, and the number of particles of 1.0 μm or more adhering to the wafer surface by a commercially available foreign substance inspection apparatus for the formed wafers. The average value of 25 sheets was calculated, and the results are shown in Table 5.

From the results shown in Table 5, it was prepared by the present invention method 25 to 32, which was prepared by blending Co: Cr alloy powders A to H containing Cr: 50 to 70 atomic% and the balance being Co, as raw material powders. The target was 50% particle size: 10 μm Co powder, 50% particle size: 10 μm Cr powder, 50% particle size: 15 μm Pt powder and 50% particle size: 3 μm without adding Co—Cr alloy powder. It can be seen that the generation of particles is less than that of the target prepared by the conventional method 4 prepared by mixing and mixing the Ta ₂ O ₅ powder. However, since the Co-Cr alloy powder produced using the Co-Cr alloy powders I to J having a component composition outside the scope of the present invention, the targets produced by the comparative methods 7 to 8 generate more particles. It turns out that it is not preferable.

Claims (4)

Cr—Co alloy powder, Pt powder, nonmagnetic oxide powder and Co powder containing Cr: 50 to 70 atomic% as the raw material powder and the balance being Co are prepared. These raw material powders are nonmagnetic oxide: 2 -15 mol%, Cr: 3 to 20 mol%, Pt: 5 to 30 mol%, balance: component composition consisting of Co, mixed and mixed, then pressure sintered For producing a Co-based sintered alloy sputtering target for forming a magnetic recording film with less generation of particles. The nonmagnetic oxide is any one of silicon dioxide, tantalum oxide, titanium oxide, aluminum oxide, magnesium oxide, thorium oxide, zirconium oxide, cerium oxide, and yttrium oxide. A method for producing a Co-based sintered alloy sputtering target for forming a magnetic recording film with less generation of particles. 2. The method for producing a Co-based sintered alloy sputtering target for forming a magnetic recording film with less generation of particles according to claim 1, wherein the pressure sintering is hot pressing or hot isostatic pressing. A Co-based sintered alloy sputtering target for forming a magnetic recording film with less generation of particles, produced by the method according to claim 1, 2 or 3.