WO2014196377A1

WO2014196377A1 - Sputtering target for magnetic recording medium

Info

Publication number: WO2014196377A1
Application number: PCT/JP2014/063676
Authority: WO
Inventors: 佐藤　敦
Original assignee: Jx日鉱日石金属株式会社
Priority date: 2013-06-06
Filing date: 2014-05-23
Publication date: 2014-12-11
Also published as: JPWO2014196377A1; TW201510257A; JP5946922B2; TWI605143B; SG11201505307QA; MY175024A

Abstract

A sintered sputtering target containing a Fe-Pt alloy and a non-magnetic material as the main components, said sintered sputtering target being characterized in that at least C (carbon) is contained as the non-magnetic material, an additional trace element other than the above-mentioned main components is contained in an amount of 50 to 5000 ppm by mass, and the standard free energy of formation (ΔG°) of the additional trace element per 1 mole of carbon in a carbide is -5000 [cal/mol] or less. The present invention addresses the problem of providing a sputtering target which undergoes the formation of particles in a greatly reduced amount upon sputtering and contains a Fe-Pt alloy and a non-magnetic material as the main components.

Description

Sputtering target for magnetic recording media

The present invention relates to a sputtering target used for forming a magnetic thin film in a magnetic recording medium.

In the field of magnetic recording typified by hard disk drives, materials based on Co, Fe, or Ni, which are ferromagnetic metals, are used as materials for magnetic thin films of magnetic recording media. For example, a Co—Cr-based or Co—Cr—Pt-based ferromagnetic alloy containing Co as a main component has been used for a magnetic thin film of a hard disk employing an in-plane magnetic recording method.
In addition, a composite material composed of a Co—Cr—Pt-based ferromagnetic alloy mainly composed of Co and an oxide is often used for a magnetic thin film of a hard disk adopting a perpendicular magnetic recording system that has been put into practical use in recent years. . The above-mentioned magnetic thin film is often produced by sputtering a sputtering target containing the above material as a component with a magnetron sputtering apparatus because of its high productivity.

On the other hand, the recording density of the hard disk is rapidly increasing year by year and is exceeding 1 Tbit / in ² . When the recording density reaches 1 Tbit / in ² , the size of the recording bit becomes less than 10 nm, and in that case, superparamagnetization due to thermal fluctuation is expected to be a problem. It is expected that a magnetic recording medium material currently used, for example, a material in which Pt is added to a Co-based alloy to increase the magnetocrystalline anisotropy is not sufficient.
This is because magnetic particles that behave stably as ferromagnetism with a size of 10 nm or less need to have higher crystal magnetic anisotropy.

For the reasons described above, Fe-Pt alloy having an L1 ₀ structure is attracting attention as a material for an ultra-high density recording medium. L1 ₀ with Fe-Pt alloy has a high crystalline magnetic anisotropy having the structure, because of its excellent corrosion resistance, oxidation resistance, is what is expected as a material suitable for the application as a magnetic recording medium.
The L1 ₀ the Fe-Pt alloy having a structure when used as a material for an ultra-high density recording medium, high density as possible in a state where the magnetically to isolate the L1 ₀ rules to structured Fe-Pt magnetic particles There is a need for the development of technology that aligns and disperses the directions.

For this reason, a granular structure magnetic thin film of Fe-Pt magnetic particles are isolated by a non-magnetic material such C (carbon) and oxides having an L1 ₀ structure, next-generation hard disk employing a thermally assisted magnetic recording method It has been proposed for magnetic recording media. This granular structure magnetic thin film has a structure in which the magnetic interaction between the magnetic particles is blocked by the nonmagnetic material surrounding the magnetic particles.
Patent Document 1, Patent Document 2, Patent Document 3, Patent Document 4, and Patent Document 5 can be cited as magnetic recording media having a magnetic thin film having a granular structure and related documents.

The granular structure magnetic thin film having a Fe-Pt magnetic particles with the L1 ₀ structure, a magnetic thin film containing C as a non-magnetic material, is attracting attention particularly because of their high magnetic properties. However, when a sputtering target composed of an Fe—Pt alloy and C is to be sputtered, there is a problem that C is inadvertently detached during sputtering and a large amount of particles (dust attached to the substrate) is generated.
In order to solve this problem, it is necessary to provide a sputtering target with improved adhesion between the Fe—Pt alloy and C. Even if a target containing carbide or nitride instead of C is used, an excellent magnetic thin film can be obtained. However, in this case as well, there is a problem that many particles are generated during sputtering.

Patent Document 6 shown below is a sputtering target containing Fe, Pt and C, and further containing a metal element other than Fe and Pt, and Cu, Ag, Mn, Ni as metal elements other than Fe and Pt. , Co, Pd, Cr, V, and B are described to contain more than 0 at% and 20 at% or less. However, Patent Document 6 has only an example containing 10 at% of Cu, and the kind and content of additive elements are greatly different from those of the present invention described later.

Patent Document 7 below discloses a technique of mixing and hot pressing FePt alloy powder, Pt powder, and carbon black powder for the purpose of producing a sintered body in which a C phase is dispersed in an FePt alloy phase. Yes. However, in this case, no study has been made on a method for solving the problem that C is detached during sputtering and a large amount of particles (dust attached to the substrate) is generated.
Patent Document 8 listed below describes a FePt (Au and / or Cu) C-based sputtering target for forming a magnetic recording medium thin film. A technique is disclosed in which a part of the Au and / or Cu may be replaced with Ag, and thereby a technique of suppressing generation of particles is disclosed.
Patent Document 9 listed below discloses a sputtering target for forming a FePtAgC-based magnetic recording medium thin film. A technique is disclosed in which a part of Ag may be replaced with Au and / or Cu, and thereby a technique of suppressing generation of particles is disclosed.

The above-mentioned Patent Document 8 and Patent Document 9 are similar techniques, but the melting point of Ag, Au, and Cu added to suppress the generation of particles is low, so that there is a problem of melting out first during hot pressing. It is explained that the sintering temperature needs to be lowered.
In order to prevent this, AgPt powder, AuPt powder, and CuPt powder are prepared in advance from Ag, Au, and Cu powders that are raw materials, and these are mixed with other raw material powders and sintered. It is stated that it is necessary. This has the problem that the manufacturing process is complicated, and there is also a problem that the amount of these elements to be added must be increased.

JP 2000-306228 A JP 2000-31329 A JP 2008-59733 A JP 2008-169464 A JP 2004-152471 A JP 2012-214874 A JP 2012-102387 A JP 2012-178210 A (Patent No. 5041261) JP 2012-178211 A (Patent No. 5041262)

The Fe-Pt alloy 1: 1 forms a L1 ₀ type ordered lattice in the vicinity of the composition, typically the material of the crystal structure ordered lattice is poor in ductility, sintering using such material pressure sintering apparatus However, there is a problem that the density of the sintered body is difficult to increase. In particular, in a Fe—Pt—C system containing C (carbon), which is a hardly sintered material, it is extremely difficult to obtain a dense sintered body. Therefore, when such a low-density sintered sputtering target is sputtered, the nonmagnetic material is carelessly detached, and there is a problem that a large amount of particles (dust attached to the substrate) is generated.

In addition, in the L1 ₀ ordered lattice of Fe—Pt alloy, when heated to 1300 ° C. or higher, the transition from the ordered state to the irregular state increases and the ductility increases. However, depending on the type of nonmagnetic material contained therein, the temperature is 1300 ° C. or higher. Some will decompose at temperature. Furthermore, in a high temperature region of 1300 ° C. or higher, coarse structure of the sintered body may occur due to the growth of crystal grains. Such coarse crystal grains serve as a starting point for abnormal discharge (arcing) during sputtering. There is a problem that particles are generated.
For this reason, the present invention has an object to provide a sintered sputtering target composed of a Fe—Pt alloy and a nonmagnetic material that can greatly reduce the amount of particles generated during sputtering and can be efficiently manufactured. To do.

The present inventor contains 50 mass ppm to 5000 mass ppm of a trace amount of additive element when producing a sintered sputtering target mainly composed of a non-magnetic material containing an Fe—Pt alloy and at least C (carbon). However, by adding a trace amount element whose standard free energy of formation ΔG ° per 1 mol of carbon of the carbide is −5000 [cal / mol] or less, that is, adding an element that easily becomes a carbide, as this trace addition element. , A carbide having better wettability than C alone is formed, and the adhesion between the Fe—Pt alloy and C is improved through the carbide.
This is the basis of the present invention. As a result, it has been found that the sintered sputtering target can greatly reduce the amount of particles generated during sputtering. In addition, all the sintering raw materials demonstrated below use a powder raw material.

Based on such knowledge, the present invention
1) A sintered sputtering target mainly composed of an Fe—Pt alloy and a nonmagnetic material, which contains at least C (carbon) as a nonmagnetic material, and further contains 50 mass ppm of a trace additive element in addition to the main component. Sintered body sputtering target, characterized in that it is contained in a range of ˜5000 mass ppm, and the standard free energy of formation ΔG ° per mol of carbon of the carbide of the trace additive element is −5000 [cal / mol] or less. ) The sintered body sputtering target according to 1) above, wherein the trace additive element is at least one of W and Cr. 3) As a nonmagnetic material, in addition to C (carbon), The sintered body sputter according to any one of 1) or 2) above, which contains at least one of oxide, nitride, and carbide. 4) In addition to the main component and the trace additive element, one or more elements selected from Ag, Au, Co, Cu, Ga, Ge, Ir, Ni, Pd, Re, Rh, Ru, Sn, Zn The sintered compact sputtering target according to any one of 1) to 3) above, wherein the sintered body sputtering target is contained as a metal component.

The present invention also provides:
5) Addition of a trace amount of standard production free energy ΔG ° per 1 mol of carbon when Fe powder, Pt powder, C powder (graphite powder) and carbide are formed as raw material powder is −5000 [cal / mol] or less Elemental powder is prepared, and these powders are mixed and pulverized in an Ar atmosphere, and the mixed and pulverized powder is filled in a carbon mold, and is heated in a vacuum atmosphere at a heating rate of 200 to 600 using a hot press device. Fe-Pt characterized in that a sintered body is produced by pressing at 20-50 MPa from the start of temperature rise to the end of holding at a temperature of ° C / hour, a holding temperature of 800-1400 ° C, a holding time of 0-4 hours. 6. Manufacturing method of sintered compact sputtering target mainly composed of alloy and non-magnetic material 6) The sintered compact according to 4) above, wherein the trace additive element is at least one of W and Cr. Method for manufacturing a sputtering target 7) In addition to the C (carbon), the raw material powder of the nonmagnetic material further contains any one or more of oxide, nitride, and carbide, and is sintered. The manufacturing method of the sintered compact sputtering target as described in any one of said 5) or 6) 8) Furthermore, Ag, Au, Co, Cu, Ga, Ge, Ir, Ni, Pd, Re, Rh, Ru, The method for producing a sintered sputtering target according to any one of 5) to 7) above, wherein one or more elements selected from Sn and Zn are contained as a raw material for the metal component and sintered. ,I will provide a.

According to the present invention, it is possible to provide a sputtering target in which the amount of particles generated during sputtering is greatly reduced. Thereby, it has the outstanding effect that the yield at the time of film-forming can be improved significantly and productivity can be improved.

The sintered sputtering target mainly comprising a Fe—Pt alloy and a nonmagnetic material according to the present invention contains at least C (carbon) as a nonmagnetic material, and further contains a trace amount of added elements in an amount of 50 ppm by mass to the main component. A sintered compact sputtering target characterized in that it is contained in the range of 5000 ppm by mass, and the standard free energy of formation ΔG ° per mol of the carbide of the trace additive element is −5000 [cal / mol] or less. .
Typical materials of the trace additive element are W and Cr, and it is effective to add one or more of these. However, other elements may be used as long as the standard free energy of formation ΔG ° per 1 mol of carbon of the carbide of the trace additive element satisfies the condition of −5000 [cal / mol] or less in the sintering temperature range. There is no particular problem to do.

In general, the Fe—Pt alloy composition can be used in which the atomic ratio is such that Pt is 35% or more and 55% or less and the balance is Fe, but the characteristics as an effective magnetic recording medium can be maintained. If it is within the range, there is no particular limitation. Fe-Pt alloy in the sputtering target is comprised of normal L1 ₀ type ordered lattice, it is not also limited thereto.
What is particularly important in the present invention is that the standard free energy of formation ΔG ° per mol of carbon is −5000 [cal / mol] or less when the additive element forms a carbide as a trace additive element of the sputtering target. The use of a trace amount of element (addition). Further, the content of C is not particularly limited as long as the characteristics as an effective magnetic recording medium can be maintained, but it is desirable to set the content in the range of 20 to 45% by volume ratio in the sputtering target. .

That is, by adding an element that easily becomes a carbide, a carbide having better wettability than C alone can be formed, and the adhesion between the Fe—Pt alloy and C can be improved through this carbide. It is what you want to do.
As a result, the sintered compact sputtering target can suppress the drop-off of C during sputtering, and can greatly reduce the amount of generated particles.
As described above, W and Cr are effective as a trace additive element, and any one or more of these elements may be added. The following mainly describes the case where W and Cr, which are representative trace additive elements, are used.

The content of W or Cr is 50 mass ppm to 5000 mass ppm. If the content is less than 50 ppm by mass, the formation of carbides with good wettability will be insufficient, and an improvement in the adhesion between the Fe-Pt alloy and C cannot be expected, while the content exceeds 5000 ppm by mass. Then, there is a possibility that sufficient magnetic properties as a magnetic thin film cannot be obtained.
The same effect can be obtained even if either W or Cr is contained. When both are contained, the total content is preferably 50 mass ppm to 5000 mass ppm as the content ratio in the entire sputtering target.

Further, the sputtering target of the present invention can contain any one or more of oxide, nitride, and carbide in addition to the C (carbon) as a nonmagnetic material. In that case, preferable oxides include Al, B, Ba, Be, Ca, Ce, Cr, Dy, Er, Eu, Ga, Gd, Ho, Li, Mg, Mn, Nb, Nd, Pr, Sc, Sm, Examples thereof include oxides of one or more elements selected from Sr, Ta, Tb, Ti, V, Y, Zn, and Zr. Preferred nitrides include nitrides of one or more elements selected from Al, B, Ca, Nb, Si, Ta, Ti, and Zr. Preferred carbides include carbides of one or more elements selected from B, Ca, Nb, Si, Ta, Ti, W, and Zr. Since the magnetic film produced from such a sputtering target has a structure in which carbon, carbide, nitride, and oxide insulate the magnetic interaction between magnetic particles, good magnetic properties can be expected.

Moreover, the sputtering target of the present invention is selected from Ag, Au, Co, Cu, Ga, Ge, Ir, Ni, Pd, Re, Rh, Ru, Sn, Zn in addition to the main component and the trace additive element. One or more of these elements can be included as a metal component.
These metal elements, in sputtered thin films are those primarily added to reduce the temperature of the heat treatment to express L1 ₀ structure. The blending ratio is not particularly limited as long as it is within a range where the characteristics as an effective magnetic recording medium can be maintained.

The sputtering target of the present invention can be produced, for example, by the following method using a powder sintering method.
First, Fe powder, Pt powder, Cr powder, Cu powder, W powder, etc. are prepared as metal powder. As the metal powder, not only a single element metal powder but also an alloy powder can be used. These metal powders preferably have a particle size in the range of 1 to 10 μm. When the particle size is 1 to 10 μm, more uniform mixing is possible, and segregation and coarse crystallization can be prevented.

When the particle size of the metal powder is larger than 10 μm, the non-magnetic material may not be uniformly dispersed. When the particle size is smaller than 1 μm, the target composition deviates from the desired composition due to the influence of oxidation of the metal powder. The problem of coming may arise. It should be understood that this particle size range is only a preferable range, and that deviating from this range is not a condition for denying the present invention.

In addition to C (carbon), oxide powder, nitride powder, carbide powder, etc. are prepared as nonmagnetic material powder. These nonmagnetic material powders preferably have a particle size in the range of 1 to 30 μm. When the particle size is 1 to 30 μm, the nonmagnetic material powders hardly aggregate when mixed with the above-mentioned metal powder, and can be uniformly dispersed.
Among non-magnetic materials, C powder includes those having a crystal structure such as graphite (graphite) and nanotubes, and amorphous materials such as carbon black. Any C powder can be used. it can.

When producing a sintered sputtering target, the standard free energy of formation ΔG ° per 1 mol of carbon when Fe powder, Pt powder, C powder (graphite powder), and carbide are formed as raw material powder is −5000 [cal / Mol] or less] are weighed so as to have a predetermined composition, and these powders are mixed in an Ar atmosphere together with pulverization using a known method such as a ball mill.
The mixed and pulverized powder is filled into a carbon mold, and using a hot press apparatus, the temperature rise rate is 200 to 600 ° C./hour, the holding temperature is 800 to 1400 ° C. in a vacuum atmosphere or an inert atmosphere. The holding time is set to 0 to 4 hours, and the sintered body is manufactured by pressurizing at 20 to 50 MPa from the start of temperature rise to the end of holding.

In addition to the hot press, various pressure sintering methods such as a plasma discharge sintering method can be used. In particular, the hot isostatic pressing is effective for improving the density of the sintered body. The holding temperature at the time of sintering depends on the components of the target, but in most cases, it is in the temperature range of 800-1400 ° C. And the sputtering target of this invention can be produced by processing the obtained sintered compact into a desired shape with a lathe.

As described above, the sputtering target of the present invention can be manufactured. The sputtering target manufactured in this way has an excellent effect that the amount of particles generated during sputtering can be reduced and the yield during film formation can be improved.

Hereinafter, description will be made based on examples and comparative examples. In addition, a present Example is an example to the last, and is not restrict | limited at all by this example. In other words, the present invention is limited only by the scope of the claims, and includes various modifications other than the examples included in the present invention.

(Example 1)
Fe powder having an average particle diameter of 3 μm, Pt powder having an average particle diameter of 3 μm, W powder having an average particle diameter of 3 μm, and C powder (graphite powder) having an average particle diameter of 10 μm were prepared as raw material powders.
The basic components were weighed composition (molar ratio): 30Fe-30Pt-40C, and weighed so that the total weight was 2600 g at the weighed composition ratio.
Further, 5.2 g of W was weighed as a component added in a small amount.

Next, all of the weighed powders were put into a 10 liter ball mill pot together with SUS balls as a grinding medium, and rotated and mixed for 16 hours in an Ar atmosphere. The powder taken out from the pot was filled in a carbon mold and molded and sintered using a hot press apparatus. The hot press conditions were a vacuum atmosphere, a heating rate of 300 ° C./hour, a holding temperature of 1400 ° C., and a holding time of 2 hours, and pressurization was performed at 30 MPa from the start of heating to the end of holding. After completion of the holding, it was naturally cooled in the chamber.

Next, composition analysis was performed using small pieces collected from the produced sintered body. Fe, Pt, and W were measured using an ICP-AES apparatus, and C was measured using a carbon analyzer employing a high frequency induction furnace combustion-infrared absorption method. As a result, the W content was 1990 mass ppm in the sputtering target. As for the basic component, the molar ratio was calculated from the weight ratio obtained by analysis. As a result, the composition of this sputtering target was analytical composition (molar ratio): 30.09Fe-30.04Pt-39.87C.

Further, using a lathe, the sintered body was cut into a shape having a diameter of 180.0 mm and a thickness of 5.0 mm to obtain a disk-shaped target. This target was attached to a magnetron sputtering apparatus (C-3010 sputtering system manufactured by Canon Anelva), and sputtering was performed. The sputtering conditions were an input power of 1 kW and an Ar gas pressure of 1.7 Pa. After performing 2 kWhr of pre-sputtering, a film was formed on a 4-inch diameter silicon substrate for 20 seconds. The number of particles adhering to the substrate was measured with a particle counter. The number of particles at this time was 185.

(Comparative Example 1)
Fe powder having an average particle diameter of 3 μm, Pt powder having an average particle diameter of 3 μm, W powder having an average particle diameter of 3 μm, and C powder (graphite powder) having an average particle diameter of 10 μm were prepared as raw material powders.
The basic components were weighed composition (molar ratio): 30Fe-30Pt-40C, and weighed so that the total weight was 2600 g at the weighed composition ratio.
Further, 0.13 g of W was weighed as a minor additive.

Next, composition analysis was carried out using small pieces collected from the produced sintered body. Fe, Pt, and W were measured using an ICP-AES apparatus, and C was measured using a carbon analyzer employing a high frequency induction furnace combustion-infrared absorption method. As a result, the content of W was 40 mass ppm in the sputtering target. Further, as a result of calculating the molar ratio of the basic component from the weight ratio obtained by analysis, the composition of this sputtering target was 30.20Fe-30.08Pt-39.72C as the analytical composition (molar ratio).

Further, using a lathe, the sintered body was cut into a shape having a diameter of 180.0 mm and a thickness of 5.0 mm to obtain a disk-shaped target. Sputtering was performed using this target under the same conditions as in Example 1, and the number of particles adhering to the substrate was measured with a particle counter. The number of particles at this time was 498, which was increased from that in Example 1.

(Comparative Example 2)
Fe powder having an average particle diameter of 3 μm, Pt powder having an average particle diameter of 3 μm, W powder having an average particle diameter of 3 μm, and C powder (graphite powder) having an average particle diameter of 10 μm were prepared as raw material powders.
The basic components were weighed composition (molar ratio): 30Fe-30Pt-40C, and weighed so that the total weight was 2600 g at the weighed composition ratio.
Further, 52.0 g of W was weighed as a minor additive.

Next, composition analysis was carried out using small pieces collected from the produced sintered body. Fe, Pt, and W were measured using an ICP-AES apparatus, and C was measured using a carbon analyzer employing a high frequency induction furnace combustion-infrared absorption method. As a result, the content of W was 20100 mass ppm in the sputtering target. Further, as a result of calculating the molar ratio of the basic component from the weight ratio obtained by analysis, the composition of this sputtering target was analytical composition (molar ratio): 30.07Fe-30.01Pt-39.92C.

Further, using a lathe, the sintered body was cut into a shape having a diameter of 180.0 mm and a thickness of 5.0 mm to obtain a disk-shaped target. Sputtering was performed using this target under the same conditions as in Example 1, and the number of particles adhering to the substrate was measured with a particle counter. The number of particles at this time was 354, an increase from that in Example 1.
On the other hand, sufficient magnetic properties were not obtained as compared with Example 1. This is presumably because the content of W was too large and the saturation magnetization and magnetocrystalline anisotropy energy were reduced.

(Example 2)
Fe powder having an average particle diameter of 3 μm, Pt powder having an average particle diameter of 3 μm, C powder (graphite powder) having an average particle diameter of 10 μm, and Cr powder having an average particle diameter of 3 μm were prepared as raw material powders.
The basic components were weighed composition (molar ratio): 30Fe-30Pt-40C, and weighed so that the total weight was 2600 g at the weighed composition ratio.
Further, 2.6 g of Cr was weighed as a component added in a small amount.

Next, all of the weighed powders were put into a 10 liter ball mill pot together with SUS balls as a grinding medium, and rotated and mixed for 16 hours in an Ar atmosphere. The powder taken out from the pot was filled in a carbon mold and molded and sintered using a hot press apparatus. The hot pressing conditions were a vacuum atmosphere, a heating rate of 300 ° C./hour, a holding temperature of 1300 ° C., and a holding time of 2 hours. After completion of the holding, it was naturally cooled in the chamber.

Next, composition analysis was carried out using small pieces collected from the produced sintered body. Fe, Pt, and Cr were measured using an ICP-AES apparatus, and C was measured using a carbon analyzer employing a high-frequency induction furnace combustion-infrared absorption method. As a result, the Cr content was 990 mass ppm in the sputtering target. Further, as a result of calculating the molar ratio from the weight ratio obtained by analysis for the basic component, the composition of this sputtering target was analytical composition (molar ratio): 29.85Fe-30.10Pt-40.05C.

Furthermore, using a lathe, the sintered body was cut into a shape having a diameter of 180.0 mm and a thickness of 5.0 mm to obtain a disk-shaped target. Sputtering was performed using this target under the same conditions as in Example 1, and the number of particles adhering to the substrate was measured with a particle counter. The number of particles at this time was 255.

(Comparative Example 3)
Fe powder having an average particle diameter of 3 μm, Pt powder having an average particle diameter of 3 μm, C powder (graphite powder) having an average particle diameter of 10 μm, and Cr powder having an average particle diameter of 3 μm were prepared as raw material powders.
The basic components were weighed composition (molar ratio): 30Fe-30Pt-40C, and weighed so that the total weight was 2600 g at the weighed composition ratio.
Further, 0.13 g of Cr was weighed as a minor additive.

Next, composition analysis was performed using small pieces collected from the produced sintered body. Fe, Pt, and Cr were measured using an ICP-AES apparatus, and C was measured using a carbon analyzer employing a high-frequency induction furnace combustion-infrared absorption method. As a result, the Cr content was 30 ppm by mass in the sputtering target. As a result of calculating the molar ratio of the basic component from the weight ratio obtained by analysis, the composition of this sputtering target was analytical composition (molar ratio): 30.23Fe-29.85Pt-39.92C.

Further, using a lathe, the sintered body was cut into a shape having a diameter of 180.0 mm and a thickness of 5.0 mm to obtain a disk-shaped target. The target was attached to a magnetron sputtering apparatus, sputtering was performed under the same conditions as in Example 1, and the number of particles adhering to the substrate was measured with a particle counter. The number of particles at this time was 658, an increase from that in Example 2.

(Comparative Example 4)
Fe powder having an average particle diameter of 3 μm, Pt powder having an average particle diameter of 3 μm, C powder (graphite powder) having an average particle diameter of 10 μm, and Cr powder having an average particle diameter of 3 μm were prepared as raw material powders.
The basic components were weighed composition (molar ratio): 30Fe-30Pt-40C, and weighed so that the total weight was 2600 g at the weighed composition ratio.
Furthermore, 26 g of Cr was weighed as a trace amount addition component.

Next, composition analysis was performed using small pieces collected from the produced sintered body. Fe, Pt, and Cr were measured using an ICP-AES apparatus, and C was measured using a carbon analyzer employing a high-frequency induction furnace combustion-infrared absorption method. As a result, the Cr content was 10200 ppm by mass in the sputtering target. Further, as a result of calculating the molar ratio from the weight ratio obtained by analysis for the basic component, the composition of this sputtering target was analytical composition (molar ratio): 30.05Fe-30.10Pt-39.85C.

Further, using a lathe, the sintered body was cut into a shape having a diameter of 180.0 mm and a thickness of 5.0 mm to obtain a disk-shaped target. Sputtering was performed using this target under the same conditions as in Example 1, and the number of particles adhering to the substrate was measured with a particle counter. The number of particles at this time was 325, which was almost the same as in Example 2. On the other hand, sufficient magnetic properties were not obtained as compared with Example 2. This is presumably because the Cr content was large and the saturation magnetization and magnetocrystalline anisotropy energy were reduced.

(Example 3)
Fe powder with an average particle size of 3 μm, Pt powder with an average particle size of 3 μm, W powder with an average particle size of 3 μm, Cr powder with an average particle size of 3 μm, C powder (graphite powder) with an average particle size of 10 μm, and average particle size A 10 μm BN powder was prepared.
The basic components were weighed composition (molar ratio): 35Fe-35Pt-20C-10BN, and weighed so that the total weight would be 2600 g at the weighed composition ratio.
Further, 5.2 g of W and 5.2 g of Cr were weighed as components added in small amounts.

Next, all of the weighed powders were put into a 10 liter ball mill pot together with SUS balls as a grinding medium, and rotated and mixed for 16 hours in an Ar atmosphere. The powder taken out from the pot was filled in a carbon mold and molded and sintered using a hot press apparatus. The hot pressing conditions were a vacuum atmosphere, a temperature rising rate of 300 ° C./hour, a holding temperature of 1200 ° C., and a holding time of 2 hours, and pressurization was performed at 30 MPa from the start of temperature rising to the end of holding. After completion of the holding, it was naturally cooled in the chamber.

Next, composition analysis was performed using small pieces collected from the produced sintered body. Fe, Pt, B, W, and Cr were measured using an ICP-AES apparatus. The content of BN was calculated from the measured value of B using the stoichiometric ratio. C was measured with a carbon analyzer employing a high frequency induction furnace combustion-infrared absorption method. As a result, the W content was 2000 mass ppm in the sputtering target, and the Cr content was 2050 mass ppm in the sputtering target. As a result of calculating the molar ratio from the weight ratio obtained by analysis for the basic component, the composition of this sputtering target was analytical composition (molar ratio): 34.91Fe-35.35Pt-20.04C-9.70BN. It was.

Further, using a lathe, the sintered body was cut into a shape having a diameter of 180.0 mm and a thickness of 5.0 mm to obtain a disk-shaped target. Using this target, sputtering was performed by attaching to a magnetron sputtering apparatus, and the number of particles adhering to the substrate was measured with a particle counter. The number of particles at this time was 211.

(Comparative Example 5)
Fe powder with an average particle size of 3 μm, Pt powder with an average particle size of 3 μm, W powder with an average particle size of 3 μm, Cr powder with an average particle size of 3 μm, C powder (graphite powder) with an average particle size of 10 μm, and average particle size A 10 μm BN powder was prepared.
The basic components were weighed composition (molar ratio): 35Fe-35Pt-20C-10BN, and weighed so that the total weight would be 2600 g at the weighed composition ratio.
Further, 0.06 g of W and 0.06 g of Cr were weighed as components added in small amounts.

Next, composition analysis was performed using small pieces collected from the produced sintered body. Fe, Pt, B, W, and Cr were measured using an ICP-AES apparatus. The content of BN was calculated from the measured value of B using the stoichiometric ratio. C was measured with a carbon analyzer employing a high frequency induction furnace combustion-infrared absorption method. As a result, the W content was 20 mass ppm in the sputtering target, and the Cr content was 20 mass ppm in the sputtering target. As a result of calculating the molar ratio from the weight ratio obtained by analysis for the basic component, the composition of this sputtering target was analytical composition (molar ratio): 35.09Fe-35.11Pt-19.87C-9.93BN. It was.

Further, using a lathe, the sintered body was cut into a shape having a diameter of 180.0 mm and a thickness of 5.0 mm to obtain a disk-shaped target. The target was attached to a magnetron sputtering apparatus, sputtering was performed under the same conditions as in Example 1, and the number of particles adhering to the substrate was measured with a particle counter. The number of particles at this time was 375, an increase from that in Example 3.

(Comparative Example 6)
Fe powder with an average particle size of 3 μm, Pt powder with an average particle size of 3 μm, W powder with an average particle size of 3 μm, Cr powder with an average particle size of 3 μm, C powder (graphite powder) with an average particle size of 10 μm, and average particle size A 10 μm BN powder was prepared.
The basic components were weighed composition (molar ratio): 35Fe-35Pt-20C-10BN, and weighed so that the total weight would be 2600 g at the weighed composition ratio.
Furthermore, 5.2 g of W and 13.0 g of Cr were weighed as trace added components.

Next, composition analysis was performed using small pieces collected from the produced sintered body. Fe, Pt, B, W, and Cr were measured using an ICP-AES apparatus. The content of BN was calculated from the measured value of B using the stoichiometric ratio. C was measured with a carbon analyzer employing a high frequency induction furnace combustion-infrared absorption method. As a result, the W content was 1980 mass ppm in the sputtering target, and the Cr content was 5030 mass ppm in the sputtering target. Further, as a result of calculating the molar ratio from the weight ratio obtained by analysis for the basic component, the composition of this sputtering target was analytical composition (molar ratio): 34.94Fe-35.26Pt-19.97C-9.83BN. It was.

Further, using a lathe, the sintered body was cut into a shape having a diameter of 180.0 mm and a thickness of 5.0 mm to obtain a disk-shaped target. Using this target, sputtering was performed by attaching to a magnetron sputtering apparatus, and the number of particles adhering to the substrate was measured with a particle counter. The number of particles at this time was 208, which was almost the same as in Example 3. On the other hand, sufficient magnetic properties were not obtained as compared with Example 3. This is presumably because the contents of W and Cr were large and the saturation magnetization and magnetocrystalline anisotropy energy were reduced.

Example 4
Fe powder having an average particle diameter of 3 [mu] m as a raw material powder, Pt powder having an average particle diameter of 3 [mu] m, B powder having an average grain size of 10 [mu] m, C powder (graphite powder) having an average particle size of 10 [mu] m, were prepared SiO ₂ powder having an average grain size 5μm .
The basic components, weighing the composition (molar ratio): a _{35Fe-35Pt-25C-5SiO 2} , in the weighing composition ratio, the weight of the total were weighed so as to 2500 g.
Further, 0.25 g of B was weighed as a component added in a small amount.

Next, all of the weighed powders were put into a 10 liter ball mill pot together with SUS balls as a grinding medium, and rotated and mixed for 16 hours in an Ar atmosphere. The powder taken out from the pot was filled in a carbon mold and molded and sintered using a hot press apparatus. The hot pressing conditions were a vacuum atmosphere, a temperature rising rate of 300 ° C./hour, a holding temperature of 1150 ° C., a holding time of 2 hours, and pressurization was performed at 30 MPa from the start of temperature rising to the end of holding. After completion of the holding, it was naturally cooled in the chamber.

Next, composition analysis was performed using small pieces collected from the produced sintered body. Fe, Pt, Si, and B were measured with an ICP-AES apparatus, and C was measured with a carbon analyzer employing a high frequency induction furnace combustion-infrared absorption method. The content of SiO ₂ was calculated from the measured value of Si using the stoichiometric ratio. As a result, the B content was 110 mass ppm in the sputtering target. Further, as a result of calculating the molar ratio from the weight ratio obtained in the analysis for the basic component, the composition of this sputtering target was as follows: analytical composition (molar ratio): 34.95Fe-35.02Pt-24.90C-5.13SiO ₂ there were.

Further, using a lathe, the sintered body was cut into a shape having a diameter of 180.0 mm and a thickness of 5.0 mm to obtain a disk-shaped target. Sputtering was performed using this target under the same conditions as in Example 1, and the number of particles adhering to the substrate was measured with a particle counter. At this time, the number of particles was 108.

(Comparative Example 7)
Fe powder having an average particle diameter of 3 [mu] m as a raw material powder, Pt powder having an average particle diameter of 3 [mu] m, B powder having an average grain size of 10 [mu] m, C powder (graphite powder) having an average particle size of 10 [mu] m, were prepared SiO ₂ powder having an average grain size 5μm .
The basic components, weighing the composition (molar ratio): a _{35Fe-35Pt-25C-5SiO 2} , in the weighing composition ratio, the weight of the total were weighed so as to 2500 g.
Furthermore, 0.07 g of B was weighed as a component added in a small amount.

Next, composition analysis was performed using small pieces collected from the produced sintered body. Fe, Pt, B, and Si were measured using an ICP-AES apparatus, and C was measured using a carbon analysis apparatus employing a high frequency induction furnace combustion-infrared absorption method. The content of SiO ₂ was calculated from the measured value of Si using the stoichiometric ratio. As a result, the content of B was 20 mass ppm in the sputtering target. Further, as a result of calculating the molar ratio from the weight ratio obtained in the analysis for the basic component, the composition of this sputtering target was as follows: analytical composition (molar ratio): 34.77Fe-35.02Pt-25.07C-5.14SiO ₂ there were.

Further, using a lathe, the sintered body was cut into a shape having a diameter of 180.0 mm and a thickness of 5.0 mm to obtain a disk-shaped target. The target was attached to a magnetron sputtering apparatus, sputtering was performed under the same conditions as in Example 1, and the number of particles adhering to the substrate was measured with a particle counter. The number of particles at this time was 245, which was increased from that in Example 4.

(Comparative Example 8)
Fe powder having an average particle diameter of 3 [mu] m as a raw material powder, Pt powder having an average particle diameter of 3 [mu] m, B powder having an average grain size of 10 [mu] m, C powder (graphite powder) having an average particle size of 10 [mu] m, were prepared SiO ₂ powder having an average grain size 5μm .
The basic components, weighing the composition (molar ratio): a _{35Fe-35Pt-25C-5SiO 2} , in the weighing composition ratio, the weight of the total were weighed so as to 2500 g.
Further, 17.5 g of B was weighed as a component added in a small amount.

Next, composition analysis was performed using small pieces collected from the produced sintered body. Fe, Pt, Si, and B were measured with an ICP-AES apparatus, and C was measured with a carbon analyzer employing a high frequency induction furnace combustion-infrared absorption method. The content of SiO ₂ was calculated from the measured value of Si using the stoichiometric ratio. As a result, the content of B was 6950 mass ppm in the sputtering target. Further, as a result of calculating the molar ratio from the weight ratio obtained in the analysis of the basic component, the composition of this sputtering target was as follows: analytical composition (molar ratio): 35.03Fe-34.87Pt-25.05C-5.05SiO ₂ there were.

Further, using a lathe, the sintered body was cut into a shape having a diameter of 180.0 mm and a thickness of 5.0 mm to obtain a disk-shaped target. Sputtering was performed using this target under the same conditions as in Example 1, and the number of particles adhering to the substrate was measured with a particle counter. The number of particles at this time was 117, which was the same as in Example 4. On the other hand, sufficient magnetic properties were not obtained as compared with Example 4. This is presumably because the content of B was large and the saturation magnetization and magnetocrystalline anisotropy energy were reduced.

(Example 5)
Fe powder with an average particle diameter of 3 μm, Pt powder with an average particle diameter of 3 μm, Cu powder with an average particle diameter of 3 μm, W powder with an average particle diameter of 3 μm, C powder (graphite powder) with an average particle diameter of 10 μm, and average particle diameter 1 μm TaC powder was prepared. The basic components were weighed composition (molar ratio): 30Fe-30Pt-5Cu-20C-15TaC, and weighed so that the total weight would be 3000 g at the weighed composition ratio.
Furthermore, 12.0 g of W was weighed as a component added in a small amount.

Next, all of the weighed powders were put into a 10 liter ball mill pot together with SUS balls as a grinding medium, and rotated and mixed for 16 hours in an Ar atmosphere. The powder taken out from the pot was filled in a carbon mold and molded and sintered using a hot press apparatus. The hot pressing conditions were a nitrogen atmosphere, a heating rate of 300 ° C./hour, a holding temperature of 1100 ° C., and a holding time of 2 hours, and pressurization was performed at 30 MPa from the start of heating to the end of holding. After completion of the holding, it was naturally cooled in the chamber.

Next, composition analysis was performed using small pieces collected from the produced sintered body. Fe, Pt, Cu, Ta, and W were measured using an ICP-AES apparatus, and C was measured using a carbon analyzer employing a high frequency induction furnace combustion-infrared absorption method. The content of TaC was calculated from the measured value of Ta using the stoichiometric ratio. As a result, the W content was 4000 ppm by mass in the sputtering target. Further, as a result of calculating the molar ratio from the weight ratio obtained by the analysis of the basic component, the composition of this sputtering target is the analytical composition (molar ratio): 29.92Fe-30.09Pt-5.04Cu-19.92C-15. 03 TaC.

Further, using a lathe, the sintered body was cut into a shape having a diameter of 180.0 mm and a thickness of 5.0 mm to obtain a disk-shaped target. Sputtering was performed using this target under the same conditions as in Example 1, and the number of particles adhering to the substrate was measured with a particle counter. At this time, the number of particles was 278.

(Comparative Example 9)
Fe powder with an average particle diameter of 3 μm, Pt powder with an average particle diameter of 3 μm, Cu powder with an average particle diameter of 3 μm, W powder with an average particle diameter of 3 μm, C powder (graphite powder) with an average particle diameter of 10 μm, and average particle diameter 1 μm TaC powder was prepared. The basic components were weighed composition (molar ratio): 30Fe-30Pt-5Cu-20C-15TaC, and weighed so that the total weight would be 3000 g at the weighed composition ratio.
Further, 0.1 g of W was weighed as a trace additive component.

Next, composition analysis was performed using small pieces collected from the produced sintered body. Fe, Pt, Cu, Ta, and W were measured using an ICP-AES apparatus, and C was measured using a carbon analyzer employing a high frequency induction furnace combustion-infrared absorption method. The content of TaC was calculated from the measured value of Ta using the stoichiometric ratio. As a result, the W content was 30 ppm by mass in the sputtering target. Further, as a result of calculating the molar ratio from the weight ratio obtained in the analysis of the basic component, the composition of this sputtering target was the analytical composition (molar ratio): 29.92Fe-30.38Pt-5.18Cu-19.72C-14 80 TaC.

Further, using a lathe, the sintered body was cut into a shape having a diameter of 180.0 mm and a thickness of 5.0 mm to obtain a disk-shaped target. Sputtering was performed using this target under the same conditions as in Example 1, and the number of particles adhering to the substrate was measured with a particle counter. The number of particles at this time was 590, which was increased from that in Example 5.

(Comparative Example 10)
Fe powder with an average particle diameter of 3 μm, Pt powder with an average particle diameter of 3 μm, Cu powder with an average particle diameter of 3 μm, W powder with an average particle diameter of 3 μm, C powder (graphite powder) with an average particle diameter of 10 μm, and average particle diameter 1 μm TaC powder was prepared. The basic components were weighed composition (molar ratio): 30Fe-30Pt-5Cu-20C-15TaC, and weighed so that the total weight would be 3000 g at the weighed composition ratio.
Further, 24.0 g of W was weighed as a component added in a small amount.

Next, composition analysis was performed using small pieces collected from the produced sintered body. Fe, Pt, Cu, Ta, and W were measured using an ICP-AES apparatus, and C was measured using a carbon analyzer employing a high frequency induction furnace combustion-infrared absorption method. The content of TaC was calculated from the measured value of Ta using the stoichiometric ratio. As a result, the W content was 7980 mass ppm in the sputtering target. Further, as a result of calculating the molar ratio from the weight ratio obtained in the analysis of the basic component, the composition of this sputtering target was the analytical composition (molar ratio): 30.03Fe-30.00Pt-5.06Cu-19.98C-14 .93 TaC.

Further, using a lathe, the sintered body was cut into a shape having a diameter of 180.0 mm and a thickness of 5.0 mm to obtain a disk-shaped target. Sputtering was performed using this target under the same conditions as in Example 1, and the number of particles adhering to the substrate was measured with a particle counter. The number of particles at this time was 290, which was almost the same as in Example 5. On the other hand, sufficient magnetic properties were not obtained as compared with Example 5. This is presumably because the content of W was large and the saturation magnetization and magnetocrystalline anisotropy energy were reduced.

(Example 6)
Fe powder having an average particle diameter of 3 μm, Pt powder having an average particle diameter of 3 μm, W powder having an average particle diameter of 3 μm, and C powder (graphite powder) having an average particle diameter of 10 μm were prepared as raw material powders.
The basic components were weighed composition (molar ratio): 45.5Fe-24.5Pt-30C, and weighed so that the total weight would be 2470 g at the weighed composition ratio.
Further, 5.0 g of W was weighed as a minor additive.

Next, composition analysis was performed using small pieces collected from the produced sintered body. Fe, Pt, and W were measured using an ICP-AES apparatus, and C was measured using a carbon analyzer employing a high frequency induction furnace combustion-infrared absorption method. As a result, the W content was 2010 mass ppm in the sputtering target. As for the basic component, the molar ratio was calculated from the weight ratio obtained by analysis. As a result, the composition of this sputtering target was analytical composition (molar ratio): 45.53Fe-24.50Pt-29.97C.

Further, using a lathe, the sintered body was cut into a shape having a diameter of 180.0 mm and a thickness of 5.0 mm to obtain a disk-shaped target. This target was attached to a magnetron sputtering apparatus (C-3010 sputtering system manufactured by Canon Anelva), and sputtering was performed. The sputtering conditions were an input power of 1 kW and an Ar gas pressure of 1.7 Pa. After performing 2 kWhr of pre-sputtering, a film was formed on a 4-inch diameter silicon substrate for 20 seconds. The number of particles adhering to the substrate was measured with a particle counter. The number of particles at this time was 124.

(Comparative Example 11)
Fe powder having an average particle diameter of 3 μm, Pt powder having an average particle diameter of 3 μm, W powder having an average particle diameter of 3 μm, and C powder (graphite powder) having an average particle diameter of 10 μm were prepared as raw material powders.
The basic components were weighed composition (molar ratio): 45.5Fe-24.5Pt-30C, and weighed so that the total weight would be 2470 g at the weighed composition ratio.
Furthermore, 0.25 g of W was weighed as a component added in a small amount.

Next, composition analysis was carried out using small pieces collected from the produced sintered body. Fe, Pt, and W were measured using an ICP-AES apparatus, and C was measured using a carbon analyzer employing a high frequency induction furnace combustion-infrared absorption method. As a result, the content of W was 80 mass ppm in the sputtering target. As a result of calculating the molar ratio of the basic component from the weight ratio obtained by analysis, the composition of this sputtering target was 45.40Fe-24.52Pt-30.08C.

Further, using a lathe, the sintered body was cut into a shape having a diameter of 180.0 mm and a thickness of 5.0 mm to obtain a disk-shaped target. Sputtering was performed using this target under the same conditions as in Example 1, and the number of particles adhering to the substrate was measured with a particle counter. The number of particles at this time was 354, an increase from Example 6.

(Comparative Example 12)
Fe powder having an average particle diameter of 3 μm, Pt powder having an average particle diameter of 3 μm, W powder having an average particle diameter of 3 μm, and C powder (graphite powder) having an average particle diameter of 10 μm were prepared as raw material powders.
The basic components were weighed composition (molar ratio): 45.5Fe-24.5Pt-30C, and weighed so that the total weight would be 2470 g at the weighed composition ratio.
Furthermore, 50.0 g of W was weighed as a component added in a small amount.

Next, composition analysis was carried out using small pieces collected from the produced sintered body. Fe, Pt, and W were measured using an ICP-AES apparatus, and C was measured using a carbon analyzer employing a high frequency induction furnace combustion-infrared absorption method. As a result, the content of W was 20100 mass ppm in the sputtering target. As for the basic component, the molar ratio was calculated from the weight ratio obtained by analysis. As a result, the composition of this sputtering target was analytical composition (molar ratio): 45.47Fe-24.58Pt-29.95C.

Further, using a lathe, the sintered body was cut into a shape having a diameter of 180.0 mm and a thickness of 5.0 mm to obtain a disk-shaped target. Sputtering was performed using this target under the same conditions as in Example 1, and the number of particles adhering to the substrate was measured with a particle counter. The number of particles at this time was 163, which was increased from that in Example 6.
On the other hand, compared with Example 6, sufficient magnetic properties were not obtained. This is presumably because the content of W was too large and the saturation magnetization and magnetocrystalline anisotropy energy were reduced.

(Example 7)
Fe powder having an average particle diameter of 3 μm, Pt powder having an average particle diameter of 3 μm, C powder (graphite powder) having an average particle diameter of 10 μm, and Cr powder having an average particle diameter of 3 μm were prepared as raw material powders.
The basic components were weighed composition (molar ratio): 20.25Fe-24.75Pt-55C, and weighed so that the total weight would be 2200 g at the weighed composition ratio.
Furthermore, 2.2 g of Cr was weighed as a small amount of additive component.

Next, composition analysis was carried out using small pieces collected from the produced sintered body. Fe, Pt, and Cr were measured using an ICP-AES apparatus, and C was measured using a carbon analyzer employing a high-frequency induction furnace combustion-infrared absorption method. As a result, the Cr content was 990 mass ppm in the sputtering target. As a result of calculating the molar ratio of the basic component from the weight ratio obtained by analysis, the composition of this sputtering target was analytical composition (molar ratio): 20.35Fe-24.78Pt-54.87C.

Furthermore, using a lathe, the sintered body was cut into a shape having a diameter of 180.0 mm and a thickness of 5.0 mm to obtain a disk-shaped target. Sputtering was performed using this target under the same conditions as in Example 1, and the number of particles adhering to the substrate was measured with a particle counter. At this time, the number of particles was 356.

(Comparative Example 13)
Fe powder having an average particle diameter of 3 μm, Pt powder having an average particle diameter of 3 μm, C powder (graphite powder) having an average particle diameter of 10 μm, and Cr powder having an average particle diameter of 3 μm were prepared as raw material powders.
The basic components were weighed composition (molar ratio): 20.25Fe-24.75Pt-55C, and weighed so that the total weight would be 2200 g at the weighed composition ratio.
Further, 0.1 g of Cr was weighed as a component added in a small amount.

Next, composition analysis was performed using small pieces collected from the produced sintered body. Fe, Pt, and Cr were measured using an ICP-AES apparatus, and C was measured using a carbon analyzer employing a high-frequency induction furnace combustion-infrared absorption method. As a result, the Cr content was 30 ppm by mass in the sputtering target. As a result of calculating the molar ratio of the basic component from the weight ratio obtained by analysis, the composition of this sputtering target was analytical composition (molar ratio): 20.23Fe-24.80Pt-54.97C.

Further, using a lathe, the sintered body was cut into a shape having a diameter of 180.0 mm and a thickness of 5.0 mm to obtain a disk-shaped target. The target was attached to a magnetron sputtering apparatus, sputtering was performed under the same conditions as in Example 1, and the number of particles adhering to the substrate was measured with a particle counter. The number of particles at this time was 486, an increase from Example 7.

(Comparative Example 14)
Fe powder having an average particle diameter of 3 μm, Pt powder having an average particle diameter of 3 μm, C powder (graphite powder) having an average particle diameter of 10 μm, and Cr powder having an average particle diameter of 3 μm were prepared as raw material powders.
The basic components were weighed composition (molar ratio): 20.25Fe-24.75Pt-55C, and weighed so that the total weight would be 2200 g at the weighed composition ratio.
Furthermore, 20 g of Cr was weighed as a small amount added component.

Next, composition analysis was performed using small pieces collected from the produced sintered body. Fe, Pt, and Cr were measured using an ICP-AES apparatus, and C was measured using a carbon analyzer employing a high-frequency induction furnace combustion-infrared absorption method. As a result, the content of Cr was 10600 mass ppm in the sputtering target. Further, as a result of calculating the molar ratio from the weight ratio obtained by analysis for the basic component, the composition of this sputtering target was analytical composition (molar ratio): 20.24Fe-24.78Pt-54.98C.

Further, using a lathe, the sintered body was cut into a shape having a diameter of 180.0 mm and a thickness of 5.0 mm to obtain a disk-shaped target. Sputtering was performed using this target under the same conditions as in Example 1, and the number of particles adhering to the substrate was measured with a particle counter. The number of particles at this time was 345, which was almost the same as in Example 7. On the other hand, sufficient magnetic properties were not obtained as compared with Example 7. This is presumably because the Cr content was large and the saturation magnetization and magnetocrystalline anisotropy energy were reduced.

As described above, in any of the examples, by adding a predetermined amount of W or Cr, the amount of particles generated during sputtering can be reduced, and the yield during film formation can be improved. Thus, it has been found that the inclusion of W or Cr has a very important role in suppressing particle generation.

Table 1 shows a list of the results of the above examples and comparative examples.

In the above examples and comparative examples, examples of BN, SiO ₂ , and TaC are shown as examples in which any one or more of oxide, nitride, and carbide is added as the nonmagnetic material in addition to C (carbon). However, other oxides, nitrides, and carbides have been confirmed to show the same effect.

Furthermore, Cu is added as an example of containing one or more elements selected from Ag, Au, Co, Cu, Ga, Ge, Ir, Ni, Pd, Re, Rh, Ru, Sn, and Zn as metal components. Although an example is shown, this is similarly applied if it is one or more elements selected from Ag, Au, Co, Cu, Ga, Ge, Ir, Ni, Pd, Re, Rh, Ru, Sn, and Zn. It has been confirmed that the effect of.

The sputtering target of the present invention has an excellent effect that the amount of particles generated at the time of sputtering can be reduced and the yield at the time of film formation can be improved. Therefore, it is useful as a sputtering target for forming a granular structure type magnetic thin film.

Claims

A sintered sputtering target comprising a Fe—Pt alloy and a nonmagnetic material as main components, comprising at least C (carbon) as the nonmagnetic material, and a trace amount of additional elements in addition to the main component of 50 mass ppm to 5000 A sintered compact sputtering target characterized by containing a mass ppm and having a standard free energy of formation ΔG ° per 1 mol of carbide of the carbide of the trace amount addition element of −5000 [cal / mol] or less.
The sintered body sputtering target according to claim 1, wherein the trace additive element is at least one of W and Cr.
3. The sintering according to claim 1, wherein the non-magnetic material further contains at least one of oxide, nitride, and carbide in addition to the C (carbon). Body sputtering target.
In addition to the main component and the trace additive element, at least one element selected from Ag, Au, Co, Cu, Ga, Ge, Ir, Ni, Pd, Re, Rh, Ru, Sn, and Zn is used as a metal component. The sintered sputtering target according to any one of claims 1 to 3, which is contained as
A small amount of additive element powder having a standard free energy of formation ΔG ° per mol of carbon of −5000 [cal / mol] or less when Fe powder, Pt powder, C powder (graphite powder), and carbide are formed as raw material powder These powders are mixed and pulverized in an Ar atmosphere, and the mixed and pulverized powder is filled in a carbon mold, and is heated in a vacuum atmosphere at a heating rate of 200 to 600 ° C. using a hot press apparatus. Fe-Pt alloy characterized in that a sintered body is produced by pressing at 20 to 50 MPa from the start of temperature rise to the end of holding at a holding temperature of 800 to 1400 ° C./hour, a holding time of 0 to 4 hours. A method for producing a sintered sputtering target mainly comprising a nonmagnetic material.
The method for producing a sintered sputtering target according to claim 4, wherein the trace additive element is at least one of W and Cr.
7. The non-magnetic material raw material powder, in addition to the C (carbon), further containing any one or more of oxides, nitrides and carbides, and sintering. The manufacturing method of the sintered compact sputtering target of one term.
Furthermore, one or more elements selected from Ag, Au, Co, Cu, Ga, Ge, Ir, Ni, Pd, Re, Rh, Ru, Sn, and Zn are contained as a raw material for the metal component and sintered. The method for producing a sintered sputtering target according to any one of claims 5 to 7, wherein: