TWI752655B - Fe-pt based sputtering target and method of preparing the same - Google Patents

Abstract

Provided is a Fe-Pt based sputtering target and a method of preparing the same. The Fe-Pt based sputtering target includes iron, platinum, and boron nitride. Based on the total amount of the Fe-Pt based sputtering target, the amount of the boron nitride is more than 0 at% and less than or equal to 50 at%. In addition, a metallography of the Fe-Pt based sputtering target comprises black phases. The black phases have an average size less than 3 μm, and the black phases have a dispersion uniformity less than 5 × 10 ^-4. By controlling the content of the boron nitride of the Fe-Pt based sputtering target and limiting the average size and the dispersion uniformity of the black phases in the metallography of the Fe-Pt based sputtering target, the Fe-Pt based sputtering target can elevate bending strength of the Fe-Pt based sputtering target, reduce the occurrence of abnormal discharges during sputtering, and mitigate the problem of particulate contamination of a magnetic recording layer formed by the Fe-Pt based sputtering target. Therefore, the quality and yield of the magnetic recording layer formed by the Fe-Pt based sputtering target can be improved.

Description

Iron-platinum-based target and method for making the same

This work is about an iron-platinum-based target and its manufacturing method, especially an iron-platinum-based target used in magnetic recording media and its manufacturing method.

Magnetic recording refers to the use of the hysteresis properties of magnetic materials to store information on a recording medium. According to the magnetization direction of the magnetic head, magnetic recording media in the prior art can be classified into horizontal magnetic recording media (longitudinal magnetic recording, LMR) and perpendicular magnetic recording media (perpendicular magnetic recording, PMR). As a memory medium for information storage, high thermal stability is the primary requirement. Not only that, with the increasing demand for the information storage capacity of magnetic recording media, how to improve the recording density of magnetic recording media has become a research focus in related fields. However, under the predicament that the magnetic recording density of the horizontal magnetic recording medium is now approaching the physical limit, a perpendicular magnetic recording medium that can delay the superparamagnetic limit and achieve a higher recording density has become a technical direction to solve the problem.

Generally speaking, the layered structure of a perpendicular magnetic recording medium includes a substrate, an adhesive layer, a soft underlayer, a seed layer, an intermediate layer, and a magnetic recording layer from bottom to top. recording layer), a cover layer and a lubricating layer, wherein the magnetic recording layer is usually a cobalt-chromium-platinum-based alloy system as the main component. However, as the technology of perpendicular magnetic recording media tends to mature, the magnetic recording layer of the cobalt-chromium-platinum-based alloy system is gradually approaching the limit of magnetic recording density. In order to further improve the recording density of perpendicular magnetic recording media, the industry has developed a The use of iron-platinum alloy system to make heat-assisted magnetic recording medium (HAMR) The magnetic recording layer of the medium) acts on the magnetic particles of the recording bit in the form of thermal energy while writing the magnetic field, and by raising the temperature of the magnetic particles to above the Curie temperature, the magnetic The magnetic coercivity of the particles is temporarily reduced, and the magnetic particle size of the iron-platinum-based alloy can be reduced compared with that of the cobalt-chromium-platinum-based alloy, thereby increasing the recording density of the magnetic recording medium. However, since the technology of thermally assisted magnetic recording will repeatedly focus heating in the same area, the magnetic composite material used as the magnetic recording layer needs to have high thermal stability, so nitrogen with high thermal stability will be added to the iron-platinum-based alloy system. Boron nitride (BN) is used to form a barrier between the grains of the iron-platinum-based alloy and reduce the magnetic coupling effect.

However, due to the small particle size of boron nitride and the characteristics of easy to agglomerate and difficult to disperse, if boron nitride is directly added to the iron-platinum-based alloy system to make a target, it will be in the target gold. The agglomerated boron nitride is clearly observed in the phase diagram, resulting in poor bending strength of the target, and is prone to abnormal discharge and a large number of particles falling to the sputtering process in the subsequent application of the sputtering process. The formed magnetic recording layer further affects the film quality and yield of the magnetic recording layer.

In view of the defects faced by the prior art, the purpose of this creation is to improve the flexural strength of the target material, and at the same time reduce the frequency of abnormal discharge in the subsequent sputtering process, and reduce the problem of particle falling, thereby improving the sputtering process. The quality and yield of the magnetic recording layer formed by plating.

In order to achieve the aforementioned object, the present invention provides an iron-platinum-based target material, which comprises iron (Fe), platinum (Pt) and boron nitride (BN); wherein, based on the total number of atoms of the iron-platinum-based target material as a whole, The content of boron nitride is greater than 0 atomic percentage (atomic percentage, at%) and less than or equal to 50 at%; the metallographic phase of the iron-platinum-based target includes a plurality of black phases, and the average size of these black phases is less than 3 microns (μm ), and the dispersion uniformity of these black phases in the metallographic phase is less than 5×10 ^-4 , wherein the dispersion uniformity is calculated by the following formula: (the total area of the black phase in the metallographic phase/the overall area of the metallographic phase)/in the metallographic phase The total number of black phases.

According to this creation, by controlling the boron nitride content in the iron-platinum-based target, the average size range of the black phase, and the dispersion uniformity range of the black phase, the phase composition distribution of the iron-platinum-based target can be well uniform. , thereby effectively improving the flexural strength of the iron-platinum-based target, and at the same time ensuring that the frequency of abnormal discharge can be reduced in the subsequent sputtering process, and the problem of particle falling can be alleviated.

According to this creation, the size of each black phase refers to the maximum length of each black phase passing through the center point in the metallographic phase; and the average value of the aforementioned multiple sets of data is the average size of the black phase.

According to the present invention, the dispersion uniformity of the black phase represents in the metallographic phase, on average, the proportion of a single black phase to the total area of the target. For example, if the total area of the black phase in the metallographic phase and the overall area of the metallographic phase remain unchanged, when the total number of black phases is greater, it means that each black phase occupies a smaller area ratio in the metallographic phase. , so it means that each black phase can be evenly dispersed in the metallographic phase. In short, the smaller the value of the dispersion uniformity of the black phase, the more uniform the black phase distribution in the metallographic phase.

According to the present invention, the boron nitride can be hexagonal boron nitride (h-BN), cubic boron nitride (c-BN), hexagonal close-packed boron nitride (w-BN) or a combination thereof, but not limited thereto .

Preferably, the content of boron nitride is greater than or equal to 3 at % and less than or equal to 30 at % based on the total number of atoms of the entire iron-platinum-based target. More preferably, the content of boron nitride is greater than or equal to 5 at % and less than or equal to 25 at % based on the total number of atoms of the whole iron-platinum-based target. By further controlling the content of boron nitride within a specific range, the film layer formed by sputtering the iron-platinum-based target can have better magnetic properties.

Preferably, the content of platinum is greater than or equal to 10 at% and less than or equal to 45 at% based on the total number of atoms of the entire iron-platinum-based target.

Preferably, the iron content is greater than or equal to 5 at% and less than or equal to 84 at% based on the total number of atoms of the entire iron-platinum-based target.

In some embodiments, the iron-platinum-based target further includes a first component selected from the group consisting of oxides, carbides, nitrides, and combinations thereof ; Wherein, based on the total number of atoms of the iron-platinum-based target as a whole, the content of the first component is greater than 0at% and less than or equal to 50at%, and the sum of the content of boron nitride and the first component is greater than or equal to 6at% and less than or equal to 50at%. Preferably, based on the total number of atoms of the iron-platinum-based target as a whole, the content of the first component is greater than or equal to 5 at% and less than or equal to 35 at%, and the sum of the content of boron nitride and the first component is Greater than or equal to 6at% and less than or equal to 50at%.

In some embodiments, the iron-platinum-based target further comprises carbon (C). Based on the total number of atoms in the iron-platinum-based target, the carbon content is greater than or equal to 2 at % and less than or equal to 40 at %.

In some embodiments, the black phase component in the metallographic phase of the iron-platinum-based target comprises boron nitride; in other embodiments, the black-phase component in the metallographic phase of the iron-platinum-based target comprises boron nitride and the first component; in In other embodiments, the black phase components in the metallographic phase of the iron-platinum-based target include boron nitride and carbon; in other embodiments, the black-phase components in the metallographic phase of the iron-platinum-based target include boron nitride, the first component with carbon.

Preferably, the oxide can be silicon _{dioxide (SiO 2} ), titanium dioxide (TiO ₂ ), chromium trioxide (Cr ₂ O ₃ ), tantalum pentoxide (Ta ₂ O ₅ ), cobalt oxide (CoO) , manganese trioxide (Mn ₂ O ₃ ), boron trioxide (B ₂ O ₃ ), hafnium dioxide (HfO ₂ ), magnesium oxide (MgO), aluminum oxide (Al ₂ O ₃ ), dioxide Zirconium (ZrO ₂ ), Niobium Pentoxide (Nb ₂ O ₅ ), Vanadium Pentoxide (V ₂ O ₅ ), Tungsten Trioxide (WO ₃ ), Iron Trioxide (Fe ₂ O ₃ ), Zinc Oxide ( ZnO) or a combination thereof, but not limited thereto.

Preferably, the nitride can be aluminum nitride (AlN), titanium nitride (TiN), chromium nitride (CrN), zirconium nitride (ZrN), tantalum nitride (TaN), hafnium nitride (HfN) , silicon nitride (Si ₃ N ₄ ), titanium carbon nitride (TiCN), tungsten nitride (WN) or a combination thereof, but not limited thereto. It should be understood that the nitrides referred to in this specification do not include boron nitride, an essential component in the iron-platinum-based target, that is, the above-mentioned "the sum of the content of boron nitride and the first component is greater than or equal to 6at. % and less than or equal to 50 at%” means that the total content of the first component (for example, the aforementioned aluminum nitride) and boron nitride is greater than or equal to 6 at% and less than or equal to 50 at%.

Preferably, the carbide can be silicon carbide (SiC), boron carbide (B ₄ C), titanium carbide (TiC), tungsten carbide (WC), tantalum carbide (TaC), hafnium carbide (HfC), zirconium carbide ( ZrC), vanadium carbide (VC), niobium carbide (NbC), chromium carbide (Cr ₃ C ₂ ), or a combination thereof, but not limited thereto.

In other embodiments, the iron-platinum-based target further comprises a second component selected from silver (Ag), gold (Au), germanium (Ge), copper (Cu), nickel (Ni) , Cobalt (Co), Aluminum (Al), Magnesium (Mg), Manganese (Mn), Silicon (Si), Strontium (Sr) and a group consisting of combinations thereof; wherein, the iron-platinum-based target as a whole Based on the total number of atoms, the content of the second component is greater than or equal to 2 at % and less than or equal to 40 at %. Preferably, the content of the second component is greater than or equal to 2 at% and less than or equal to 20 at%; more preferably, the content of the second component is greater than or equal to 2 at% and less than or equal to 10 at%. By adding the aforementioned second component to the iron-platinum-based target, the density of the iron-platinum-based target can be further improved.

In other embodiments, the iron-platinum-based target further comprises the second component and carbon; wherein, based on the total number of atoms of the iron-platinum-based target as a whole, the content of the second component is greater than or equal to 2 at% and less than or equal to 40 at %, and the carbon content is greater than or equal to 2 at % and less than or equal to 10 at %.

In other embodiments, the iron-platinum-based target further comprises the first component and the second component; wherein, based on the total number of atoms of the iron-platinum-based target as a whole, the content of the first component is greater than 0 at % and less than or equal to 50at%, and the total content of the first component and boron nitride is greater than or equal to 6at% and less than or equal to 50at%, the content of the second component is greater than or equal to 2at% and less than or equal to 40at% %.

In other embodiments, the iron-platinum-based target further comprises the first component, the second component and carbon; wherein, based on the total number of atoms of the iron-platinum-based target as a whole, the content of the first component is More than 0at% and less than or equal to 50at%, and the total content of the first component and boron nitride is greater than or equal to 6 at % and less than or equal to 50 at %, the content of the second component is greater than or equal to 2 at % and less than or equal to 40 at %, and the content of carbon is greater than or equal to 2 at % and less than or equal to 10 at %.

In the first embodiment of the present invention, the iron-platinum-based target material includes iron, platinum and boron nitride; in this embodiment, the content of boron nitride is greater than or equal to 0.1at% and less than or equal to 50at %. In the second embodiment of the present invention, the iron-platinum-based target material includes iron, platinum, boron nitride and carbon; in this embodiment, the content of boron nitride is greater than or equal to 1 at% and less than or equal to 30 at%, the carbon content is greater than or equal to 1 at% and less than or equal to 40 at%, more specifically, the content of carbon is greater than or equal to 2 at% and less than or equal to 40 at%. In a third embodiment of the present invention, the iron-platinum-based target material includes iron, platinum, boron nitride and the first component; in this embodiment, the content of boron nitride is greater than or equal to 1 at% and Less than or equal to 50 at%, the content of the first component is greater than or equal to 4 at% and less than or equal to 30 at%. In the fourth embodiment of the present invention, the iron-platinum-based target material includes iron, platinum, boron nitride and the second component; in this embodiment, the content of boron nitride is greater than or equal to 10 at% and Less than or equal to 50 at %, the content of the second component is greater than or equal to 1 at % and less than or equal to 20 at %, more specifically, the content of the second component is greater than or equal to 2 at % and less than or equal to 20 at %. In a fifth embodiment of the present invention, the iron-platinum-based target comprises iron, platinum, boron nitride, the first component and the second component; in this embodiment, the content of boron nitride is greater than or equal to 2at% and less than or equal to 30at%, the content of the first component is greater than or equal to 5at% and less than or equal to 30at%, the content of the second component is greater than or equal to 5at% and less than or equal to 50at%, more Specifically, the content of the second component is greater than or equal to 5 at % and less than or equal to 40 at %. In the sixth embodiment of the present invention, the iron-platinum-based target material includes iron, platinum, boron nitride, the first component and carbon; in this embodiment, the content of boron nitride is greater than or equal to 1at % and less than or equal to 20 at%, the content of the first component is greater than or equal to 10 at% and less than or equal to 50 at%, and the content of carbon is greater than or equal to 2 at% and less than or equal to 20 at%. In a seventh embodiment of the present invention, the iron-platinum-based target material includes iron, platinum, boron nitride, the second component and carbon; in this embodiment, the content of boron nitride is greater than or equal to At 1 at% and less than or equal to 30 at%, the content of the second component is greater than or equal to 1 at% and less than or equal to 20 at%, more specifically, the content of the second component is greater than or equal to 2 at% and less than or equal to 20at%, the carbon content is greater than or equal to 5at% and less than or equal to 40at%. In an eighth embodiment of the present invention, the iron-platinum-based target material comprises iron, platinum, boron nitride, the first component, the second component and carbon; in this embodiment, the content of boron nitride is greater than or equal to 1at% and less than or equal to 30at%, the content of the first component is greater than or equal to 5at% and less than or equal to 50at%, more specifically, the content of the first component is greater than or equal to 5at% and Less than or equal to 40 at%, the content of the second component is greater than or equal to 2 at% and less than or equal to 20 at%, and the content of carbon is greater than or equal to 2 at% and less than or equal to 15 at%. In the aforementioned first, third, fourth, and fifth embodiments, the iron-platinum-based target may optionally not contain carbon.

Preferably, the flexural strength of the iron-platinum-based target is greater than or equal to 700 megapascals (MPa). More preferably, the flexural strength of the iron platinum-based target material is greater than or equal to 700 MPa and less than or equal to 1600 MPa.

In addition, the present invention further provides a method for producing an iron-platinum-based target, which includes the following steps: step (a): mixing iron raw materials, platinum raw materials and boron nitride raw materials to obtain a raw material mixture, wherein the boron nitride raw materials The average particle size is less than 5 microns; step (b): the raw material mixture is ground for 4 hours to 12 hours, then sieved with a sieve of 800 mesh to 1200 mesh, and then the material on the sieve is taken and filtered. Repeat the above-mentioned steps of grinding and sieving to obtain an iron-platinum-based mixed raw material; and step (c): sintering the iron-platinum-based mixed raw material to obtain the iron-platinum-based target; wherein, the iron-platinum-based mixed raw material is Based on the total number of atoms in the whole, the addition amount of boron nitride raw materials is greater than 0at% and less than or equal to 50at%; the metallographic phase of the iron-platinum-based target contains a plurality of black phases, and the average size of these black phases is less than 3 microns, And the dispersion uniformity of these black phases is less than 5×10 ^-4 , wherein the dispersion uniformity is calculated by the following formula: (the total area of the black phase in the metallographic phase/the overall area of the metallographic phase)/the amount of the black phase in the metallographic phase. The total number of.

By controlling the average particle size and content range of the boron nitride raw material in the iron-platinum-based mixed raw material, and at the same time through the technical means of sieving, the iron-platinum-based target can be formed with a specific average size range and specific dispersion. The black phase in the uniformity range enables the prepared iron-platinum-based target to have better flexural strength, and at the same time, it can reduce the frequency of abnormal discharge and the problem of particle falling in the subsequent sputtering process.

According to the present invention, the mixing step in step (a) can be any method that can uniformly mix the raw materials, for example, the mixing step can be by placing the raw materials in a mixer to achieve the purpose of uniformly mixing the raw materials, but not limited to this.

According to the present invention, after the mixing step in step (a) is completed, a reduction step can be followed, and the reduction step can be any means capable of reducing the oxidized raw material. For example, the reduction step may be a hydrogen reduction method, a vacuum reduction method, a carbon reduction method or a zinc reduction method, but is not limited thereto. Preferably, the reduction step is a hydrogen reduction method.

According to the present invention, after the iron-platinum-based mixed raw material is obtained in step (b), a pre-pressing step may be performed successively, and the pre-pressing step may be any means capable of pressing the iron-platinum-based mixed raw material into a fixed shape. For example, the pre-pressing step can be performed by placing the iron-platinum-based mixed raw material in an oil press and pre-pressing at a pressure of about 250 pounds per square inch (psi) to 350 psi, but not limited to this.

Preferably, based on the total number of atoms of the whole iron-platinum-based mixed raw material, the addition amount of the platinum raw material is greater than or equal to 10 at% and less than or equal to 45 at%.

Preferably, based on the total number of atoms of the whole iron-platinum-based mixed raw material, the addition amount of the boron nitride raw material is greater than or equal to 3 at% and less than or equal to 30 at%. More preferably, the content of boron nitride is greater than or equal to 5 at % and less than or equal to 25 at % based on the total number of atoms of the whole iron-platinum-based target.

Preferably, based on the total number of atoms of the whole iron-platinum-based mixed raw material, the addition amount of the iron raw material is greater than or equal to 5 at% and less than or equal to 84 at%.

Preferably, in step (b), the above-mentioned steps of grinding and sieving are repeated at least three times to obtain the iron-platinum-based mixed raw material. Specifically, the repeated steps refer to the steps of grinding and sieving the raw material mixture, and then taking the material on the sieve for grinding and sieving again under the same conditions.

In some embodiments, the iron-platinum-based mixed raw material further comprises a first component, and the first component is selected from the group consisting of oxide raw materials, carbide raw materials, nitride raw materials and combinations thereof; wherein, the iron is used as the raw material. Based on the total number of atoms of the whole platinum-based mixed raw material, the content of the first component is greater than 0at% and less than or equal to 50at%, and the total amount of the first component and the boron nitride raw material added is greater than or equal to 6at% and less than or equal to 50at%. Preferably, based on the total number of atoms of the whole iron-platinum-based mixed raw material, the content of the first component is greater than or equal to 5at% and less than or equal to 35at%, and the addition amount of the first component and the boron nitride raw material The sum is greater than or equal to 6 at% and less than or equal to 50 at%.

In some embodiments, the iron-platinum-based mixed raw material further comprises carbon raw material, and the amount of carbon raw material added is greater than or equal to 2 at% and less than or equal to 40 at% based on the total number of atoms of the entire iron-platinum-based mixed raw material.

In other embodiments, the iron-platinum-based mixed raw material further comprises a second component, and the second component is selected from silver raw materials, gold raw materials, germanium raw materials, copper raw materials, nickel raw materials, cobalt raw materials, aluminum raw materials, magnesium raw materials, A group consisting of manganese raw materials, silicon raw materials, strontium raw materials and their combinations; wherein, based on the total number of atoms of the entire iron-platinum-based mixed raw material, the addition amount of the second component is greater than or equal to 2at% and less than or equal to 40at%.

Preferably, in step (c), the sintering temperature is 600°C to 1200°C, and the sintering pressure is 350 bar to 1800 bar. In one embodiment, in step (c), the sintering time may be 5 minutes clock to 4 hours. More preferably, in step (c), the sintering temperature is 700°C to 1100°C, and the sintering pressure is 380 bar to 1750 bar. In one embodiment, in step (c), the sintering time may be 3 hours.

According to the present invention, the sintering step may be hot pressing (HP), hot isostatic pressing (HIP) or spark plasma sintering (SPS). For example, when HP is used in the sintering step, the sintering temperature can be 800°C to 1100°C, the sintering pressure can be 350bar to 400bar, and the sintering time can be 2 hours to 4 hours, but not limited thereto; when the sintering step adopts HIP , the sintering temperature can be 800℃ to 1100℃, the sintering pressure can be 1700bar to 1800bar, and the sintering time can be 2 hours to 4 hours, but not limited thereto; when the sintering step adopts SPS, the sintering temperature can be 700℃ To 1100° C., the sintering pressure may be 450 bar to 550 bar, and the sintering time may be 5 minutes to 1 hour, but not limited thereto.

Figure 1 is a metallographic diagram of the iron-platinum-based target of Example 5 magnified by a scanning electron microscope 2000 times; Figure 2 is a metallographic diagram of the iron-platinum-based target of Comparative Example 3 magnified 2000 times by a scanning electron microscope; Figure 3 is a metallographic image of the iron-platinum-based target of Example 22 magnified 2000 times by a scanning electron microscope; Figure 4 is a metallographic image of the iron-platinum-based target of Comparative Example 17 magnified 2000 times by a scanning electron microscope.

In order to verify the influence of the content of boron nitride, the average size of the black phase in the metallographic phase, and the dispersion uniformity of the black phase in the metallographic phase on the iron-platinum-based target, several iron-platinum-based targets are listed below as examples, and the embodiments of this invention are described in detail. , those with ordinary knowledge in the technical field can easily understand the advantages and effects of this creation through the content of this specification, and make various modifications and changes without departing from the spirit of this creation, in order to implement or apply this creation. content.

Examples 1 to 5: Iron-platinum-based targets

According to the composition of the iron-platinum-based target listed in Table 1 below, weigh an appropriate amount of iron powder with an average particle size of less than 100 microns, platinum powder with an average particle size of less than 20 microns and boron nitride powder with an average particle size of less than 5 microns. Mix in a powder mixer, and then reduce the mixed powder by hydrogen reduction method, then put the reduced mixed powder into a high-speed mill for grinding for 4 to 12 hours, and then use 800 to 1200 mesh. The sieve is sieved, and the above-mentioned material on the sieve is taken and repeated three times to obtain the iron-platinum-based mixed powder.

Next, the iron-platinum-based mixed powder was placed in a hydraulic press and pre-pressed at a pressure of about 300 psi, and then sintered according to the sintering process and sintering temperature listed in Table 1 below, to obtain the iron-platinum of Examples 1 to 5 For the base target, if HP is used in the sintering step, the sintering pressure is about 380 bar and the sintering time is 3 hours; if the sintering step is SPS, the sintering pressure is about 500 bar and the sintering time is 10 minutes.

In Table 1 below, the composition of the iron-platinum-based targets of Examples 1 to 5 can be represented by the general formula of aFe-bPt-cBN; wherein, a represents the content ratio of iron relative to the total number of atoms of the iron-platinum-based target material, b represents the content ratio of platinum to the total number of atoms of the iron-platinum-based target, and c represents the content ratio of boron nitride to the total number of atoms of the iron-platinum-based target.

Examples 6 to 7: Iron-platinum-based targets (containing carbon)

The production processes of Examples 6 to 7 are similar to those of Examples 1 to 5, that is, after weighing an appropriate amount of powders of different components and going through the steps of mixing, reducing, grinding and sieving, pre-pressing and sintering, the iron platinum of Examples 6 to 7 is obtained. base target. The sintering process and sintering temperature used in Examples 6 to 7 are listed in Table 1 below. If the sintering step adopts HP, the sintering pressure is about 380 bar and the sintering time is 3 hours; if the sintering step adopts SPS, the sintering pressure About 500 bar, the sintering time is 10 minutes.

The difference between Examples 6 to 7 and Examples 1 to 5 is that according to the composition of the iron-platinum-based target listed in Table 1 below, an appropriate amount of iron powder with an average particle size of less than 100 microns and an average particle size of less than 20 microns are weighed. The platinum powder of rice, the boron nitride powder with an average particle size of less than 5 microns, and the carbon powder with an average particle size of less than 10 microns are mixed in a mixer.

In Table 1 below, the composition of the iron-platinum-based targets of Examples 6 to 7 can be represented by the general formula of aFe-bPt-cBN-d1C; wherein a, b and c respectively represent iron, platinum and nitride as previously described The content ratio of boron to the total number of atoms of the iron-platinum-based target, and d1 represents the content ratio of carbon to the total number of atoms of the iron-platinum-based target.

Examples 8 to 13: Iron-platinum-based targets (containing the first component)

Examples 8 to 13 are similar to the production processes of Examples 1 to 5, that is, weigh an appropriate amount of powders of different components and go through the steps of mixing, reducing, grinding and sieving, pre-pressing and sintering to obtain the iron platinum of Examples 8 to 13. base target. The sintering process and sintering temperature used in Examples 8 to 13 are listed in Table 1 below. If the sintering step adopts HP, the sintering pressure is about 380 bar and the sintering time is 3 hours; if the sintering step adopts SPS, the sintering pressure The sintering time is about 500 bar and the sintering time is 10 minutes; if the sintering step adopts HIP, the sintering pressure is about 1750 bar and the sintering time is 3 hours.

The difference between Examples 8 to 13 and Examples 1 to 5 is that according to the composition of the iron-platinum-based target listed in Table 1 below, an appropriate amount of iron powder with an average particle size of less than 100 microns and an average particle size of less than 20 microns are weighed. The platinum powder, the boron nitride powder with an average particle size of less than 5 microns, and the first component with an average particle size of less than 10 microns are placed in a mixer to mix. Here, the first component may be boron carbide powder, silicon dioxide powder, aluminum nitride powder, titanium dioxide powder, tantalum carbide powder, tantalum pentoxide powder, titanium nitride powder, chromium carbide powder, or a combination thereof.

In Table 1 below, the compositions of the iron-platinum-based targets of Examples 8 to 13 may be aFe-bPt-cBN-d2B ₄ C-d3SiO ₂ -d4AlN-d5TiO ₂ -d6TaC-d7Ta ₂ O ₅ -d8TiN-d9Cr ₃ C ₂ is shown in the general formula; wherein, a, b and c respectively represent the content ratio of iron, platinum and boron nitride relative to the total number of atoms of the iron-platinum-based target, d2, d3, d4, d5, d6, d7 , d8, and d9 respectively represent the content ratio of boron carbide, silicon dioxide, aluminum nitride, titanium dioxide, tantalum carbide, tantalum pentoxide, titanium nitride and chromium carbide relative to the total number of atoms in the iron-platinum-based target.

In this specification, the "total content of boron nitride and the first component" refers to the sum of c, d2, d3, d4, d5, d6, d7, d8, and d9.

Example 14: Iron-platinum-based target (containing the second component)

The production process of Example 14 is similar to that of Examples 1 to 5, that is, an appropriate amount of powders of different components are weighed and subjected to the steps of mixing, reduction, grinding and sieving, pre-pressing and sintering to obtain the iron-platinum-based target of Example 14. The sintering process and sintering temperature used in Example 14 are listed in Table 1 below, wherein the sintering step in Example 14 adopts HP, the sintering pressure is about 380 bar, and the sintering time is 3 hours.

The difference between Example 14 and Examples 1 to 5 is that according to the composition of the iron-platinum-based target listed in Table 1 below, an appropriate amount of iron powder with an average particle size of less than 100 microns and platinum with an average particle size of less than 20 microns are weighed. The powder, the boron nitride powder with an average particle size of less than 5 microns and the second component with an average particle size of less than 20 microns are mixed in a mixer. Here, the second component is silver powder.

In Table 1 below, the composition of the iron-platinum-based target material of Example 14 can be represented by the general formula of aFe-bPt-cBN-e1Ag; wherein a, b and c respectively represent iron, platinum and boron nitride as mentioned above. Regarding the content ratio of the total number of atoms of the iron-platinum-based target, e1 represents the content ratio of silver to the total number of atoms of the iron-platinum-based target.

Examples 15 to 25: Iron-platinum-based targets (containing the first and second components)

Examples 15 to 25 are similar to the production processes of Examples 1 to 5, that is, after weighing an appropriate amount of powders of different components and going through the steps of mixing, reducing, grinding and sieving, pre-pressing and sintering, the iron platinum of Examples 15 to 25 is obtained. base target. The sintering process and sintering temperature used in Examples 15 to 25 are listed in Table 1 below. If the sintering step adopts HP, the sintering pressure is about 380 bar and the sintering time is 3 hours; if the sintering step adopts SPS, the sintering pressure The sintering time is about 500 bar and the sintering time is 10 minutes; if the sintering step adopts HIP, the sintering pressure is about 1750 bar and the sintering time is 3 hours.

The difference between Examples 15 to 25 and Examples 1 to 5 is that according to the composition of the iron-platinum-based target listed in Table 1 below, an appropriate amount of iron powder with an average particle size of less than 100 microns and an average particle size of less than 20 microns are weighed. The platinum powder, the boron nitride powder with an average particle size of less than 5 microns, the first component with an average particle size of less than 20 microns, and the second component with an average particle size of less than 20 microns are mixed in a mixer. Here, the first component can be silicon carbide powder, chromium oxide powder, cobalt oxide powder, aluminum nitride powder, magnesium oxide powder, manganese oxide powder, silicon dioxide powder, titanium dioxide powder, aluminum oxide powder powder, titanium nitride powder, boron trioxide powder, hafnium dioxide powder or a combination thereof; the second component can be silver powder, copper powder, magnesium powder, manganese powder, cobalt powder, germanium powder, aluminum powder, nickel powder , silicon powder, strontium powder, gold powder, or a combination thereof.

In addition, according to the composition of the iron-platinum-based targets of Examples 15, 16, 20 and 23 listed in Table 1 below, an appropriate amount of carbon powder with an average particle size of less than 20 microns can be weighed and placed together with the aforementioned powder in the aforementioned process. Mix in a mixer.

In Table 1, the embodiment of the iron 15 to 25 may be composed of a platinum-based target aFe-bPt-cBN-d1C- d3SiO 2 -d4AlN-d5TiO 2 -d8TiN-d10SiC-d11Cr 2 O 3 -d12CoO-d13MgO-d14Mn Example ₂ O ₃ -d15Al ₂ O ₃ -d16B ₂ O ₃ -d17HfO ₂ -e1Ag-e2Cu-e3Mg-e4Mn-e5Co-e6Ge-e7Al-e8Ni-e9Si-e10Sr-e11Au is shown in the general formula; among them, a, b and c represents the content ratio of iron, platinum and boron nitride to the total number of atoms in the iron-platinum-based target as mentioned above, d1, d3, d4, d5, d8, d10, d11, d12, d13, d14, d15, d16, d17 represents carbon, silicon dioxide, aluminum nitride, titanium dioxide, titanium nitride, silicon carbide, chromium oxide, cobalt oxide, magnesium oxide, manganese oxide, aluminum oxide, boron oxide and The content ratio of hafnium oxide to the total number of atoms in the iron-platinum-based target, e1, e2, e3, e4, e5, e6, e7, e8, e9, e10, e11 represent silver, copper, magnesium, manganese, cobalt, The content ratio of germanium, aluminum, nickel, silicon, strontium and gold relative to the total number of atoms in the iron-platinum-based target.

In this specification, the "content of the second component" refers to the sum of e1, e2, e3, e4, e5, e6, e7, e8, e9, e10, and e11.

Comparative Examples 1 to 20: Iron-platinum-based targets

The preparation methods of Comparative Examples 1 to 20 are basically the same as those of the Examples, the main difference is that the average particle size of the boron nitride powder is not less than 5 microns and the reduced mixed powder is not subjected to a sieving step after high-speed grinding. , other than that, the iron-platinum-based targets of Comparative Examples 1 to 20 were prepared according to the preparation process of the examples. The compositions of the iron-platinum-based targets of Comparative Examples 1 to 20 and the content of each component in atomic percentage are listed in Table 1 below. The general formula is expressed, and the content of each component is expressed as described in the foregoing embodiments.

Comparative Examples 21 to 22: Iron-platinum-based targets

First, the diamond carbon powder and a plurality of grinding balls with a diameter of 5 millimeters (mm) were placed in a ball mill, and after high-energy ball milling for 3 hours, a ground diamond carbon powder with an average particle size of 0.5 microns was obtained. Boronide is sieved with a 400-mesh sieve, and then, iron raw material, platinum raw material, the ground diamond carbon powder and the sieved boron nitride are weighed according to the composition listed in Table 1 below. , and mixed to obtain a mixture. The mixture was then subjected to high-energy ball milling for 3 hours to obtain an iron-platinum-based alloy powder, and the iron-platinum-based alloy powder was sintered for 3 hours according to the sintering process and sintering temperature listed in Table 1 to obtain Comparative Example 21 And 22 iron platinum-based targets. The compositions of the iron-platinum-based targets of Comparative Examples 21 and 22 and the content of each component in atomic percent are listed in Table 1 below. The general formula is expressed, and the content of each component is expressed as described in the foregoing embodiments.

Analysis 1: Metallographic microstructure of iron-platinum-based targets

Analysis 1-1: Observe the distribution and morphology of the black phase in the metallographic phase

First, the iron-platinum-based targets of Examples 1 to 25 and Comparative Examples 1 to 22 were further processed by wire cutting and grinding to obtain circular targets with a diameter of 2 inches and a thickness of 3 mm. The center of the target is 0.5 radius for sampling, and a 10mm × 10mm test piece is obtained by wire cutting.

Next, the metallographic microstructures of the test pieces of the iron-platinum-based targets of Examples 1 to 25 and Comparative Examples 1 to 22 were photographed with a scanning electron microscope (model SE-3400 manufactured by Hitachi) at a magnification of 2000 times. Herein, the iron-platinum-based targets of Example 5, Comparative Example 3, Example 22, and Comparative Example 17 are used for exemplary illustration, and the photographing results are shown in FIG. 1 to FIG. 4 , respectively. Comparing the results of Fig. 1 and Fig. 2 and Fig. 3 and Fig. 4, it can be clearly observed that the black phase in the iron-platinum-based targets of Example 5 and Example 22 presents a point-like uniform distribution pattern. The black phase in the iron-platinum-based target of Comparative Example 17 was elongated and relatively coarse, and the distribution of the black phase was uneven.

Analysis 1-2: Average size of black phase in metallography

The image analysis software Image J was used to analyze the metallographic phases of the test pieces of the iron-platinum-based targets of Examples 1 to 25 and Comparative Examples 1 to 22, respectively. The microscope was photographed at a magnification of 2000 times. The photographing method was to randomly photograph five different areas in the same test piece, and obtain five metallographic images, and then directly use the built-in image analysis software ImageJ. The average particle size analysis function "Feret's Diameter" counts the size of the black phase in the five metallographic diagrams, and finally calculates the average size of the black phase in the five metallographic diagrams by software to represent the black phase of the iron-platinum-based target. average size, and the results are recorded in Table 2 below.

Analysis 1-3: Dispersion uniformity of black phase in metallography

The image analysis software Image J was also used to analyze the metallographic diagrams of the test pieces of the iron-platinum-based targets of Examples 1 to 25 and Comparative Examples 1 to 22 obtained by analyzing 1-2, and further analyze the images with the images. The "Area" function built into the software analyzes the total area of the metallographic diagram, the total area of the black phase in the metallographic diagram and the number of black phases, and then calculates the black phase according to the calculation method of dispersion uniformity defined in this manual. Finally, the dispersion uniformity of the black phase in the aforementioned five metallographic diagrams is calculated by software to represent the dispersion uniformity of the black phase of the iron-platinum-based target, and the results are recorded in Table 2 below.

Analysis 2: Density Measurement and Flexural Strength Analysis

First, the iron-platinum-based targets of Examples 1 to 25 and Comparative Examples 1 to 22 were further processed by wire cutting and grinding to obtain test pieces with a thickness of 3 mm, a width of 4 mm, and a length of 25 mm. The compactness of the iron-platinum-based targets of Examples 1 to 25 and Comparative Examples 1 to 22 was obtained by German method, and the results were recorded in Table 2 below.

Next, place the test pieces of the iron-platinum-based targets of Examples 1 to 25 and Comparative Examples 1 to 22 on a universal testing machine to measure the three-point bending resistance. Under the operating conditions of a span of 20mm and a pressing speed of 0.008mm per second, measure the maximum load before the test piece is bent to break, and then calculate it according to the following formula: Flexural strength = (3 × maximum load × span distance)/(2 × width of the test piece × thickness of the test piece × thickness of the test piece) to obtain the flexural strength of the iron-platinum-based targets of Examples 1 to 25 and Comparative Examples 1 to 22, and the results are recorded in Table 2 below.

Analysis 3: Target sputtering quality analysis

The iron-platinum-based targets of Examples 1 to 25 and Comparative Examples 1 to 22 were further processed by wire cutting and grinding to obtain circular targets with a diameter of 2 inches and a thickness of 3 mm. The material was placed in a magnetron sputtering machine (assembled by Gordon Technology) with a continuous flow of 50sccm (Standard Cubic Centimeter per Minute) and a vacuum of 0.01 torr to 0.001 Torr. The target was pre-sputtered with a power of 200 watts (W) for 600 seconds to remove contamination on the surface of the target to obtain a target to be tested for evaluating the sputtering quality.

Next, the target to be tested is placed in a sputtering environment with an argon flow rate of 50 sccm and a vacuum of 0.01 Torr to 0.001 Torr, and the sputtering process is continued at a power of 50W to 150W for 300 seconds, and monitoring The number of abnormal discharges and the number of particles dropped during the sputtering process of each target to be measured The results are recorded in Table 2 below.

Discussion of experimental results

According to the production process of each embodiment of the present invention and the results in Table 2, it can be seen that by controlling the content and average particle size of boron nitride powder within a specific range, and at the same time through the technical means of sieving, the prepared iron The content of boron nitride in the platinum-based target is not more than 50at%, and the average size of the black phase in the metallographic phase of the iron-platinum-based target is less than 3 microns, and the dispersion uniformity of the black phase is less than 5×10 ^-4 , accordingly , the iron-platinum-based targets of Examples 1 to 25 all have the effects of flexural strength greater than or equal to 700 MPa, abnormal discharge times less than 30 times and particle drop number less than 50; The content and average particle size of the boron nitride powder are not controlled at the same time, and the step of sieving after grinding is not carried out, so it cannot meet the requirements of the boron nitride content, the average size of the black phase and the dispersion uniformity of the black phase as defined in this work. In a specific range, not only can it not stably improve the flexural strength of the iron-platinum-based target, but also cannot effectively reduce the number of abnormal discharges (the minimum is still 36) and the number of particles dropped (the minimum is still 105).

Further referring to the groups of Example 1, Example 5, Comparative Example 1, and Comparative Example 4, compared with Comparative Example 1 (with a boron nitride content of 60 at%) and Comparative Example 4 (with a boron nitride content of 0 at%) , the boron nitride content of Example 1 (with a boron nitride content of 0.1 at%) and Example 5 (with a boron nitride content of 50 at%) is due to the specific characteristics defined in this work that are greater than 0 at% and less than or equal to 50 at% Therefore, in Example 1 and Example 5, regardless of the flexural strength (1476MPa and 871MPa, respectively), the number of abnormal discharges (0 and 15, respectively) or the number of particles dropped (1 and 36, respectively) The results are better than those of Comparative Example 1 and Comparative Example 4 (flexural strength of 467 MPa and 824 MPa, respectively; number of abnormal discharges: 103 and 226; number of particles dropped: 1666 and 1394). From this, it can be seen that controlling the content of boron nitride in a specific range is indeed helpful to improve the flexural strength of the target material, reduce the occurrence of abnormal discharge, and reduce the drop of particles.

Further referring to the groups of Example 4 and Comparative Example 3, although the composition of Comparative Example 3 is exactly the same as that of Example 4, that is, the content of boron nitride in Comparative Example 3 is within the range defined by this work, but the The average size of the black phase and the uniformity of dispersion are not within the scope defined by this work. Accordingly, Example 4 has the flexural strength (911MPa), the number of abnormal discharges (11 times) and the number of particles dropped (20). The results were far better than those of Comparative Example 3 (812MPa, 106 times and 895 pieces, respectively). It can be seen that, in addition to the content of boron nitride that needs to be controlled within a specific range, the average size and dispersion uniformity of the black phase also need to be controlled within the specific range defined in this work, in order to effectively improve the flexural strength of the target at the same time, Reduce abnormal discharge and particle fall.

In addition, from the results of Examples 8 to 13, it can be seen that the first component is added to the iron-platinum-based target, and the range of the content of boron nitride, the sum of the content of boron nitride and the first component, the average size of the black phase and the black When the phase dispersion uniformity is within the specific range defined in this work, it can also improve the flexural strength of the target material, reduce the occurrence of abnormal discharge and reduce the drop of particles. Further referring to the groups of Examples 8, 12 and Comparative Examples 5 and 6, although the composition of Example 8 and Comparative Example 6 is the same, and the composition of Example 12 and Comparative Example 5 is the same, the black phase of Comparative Examples 5 and 6 is average. The size and dispersion uniformity are not within the specific range defined by this creation, so there are still serious problems such as abnormal discharge and particle falling.

Referring again to the groups of Examples 14 to 25, which additionally have a second component added, and compared to the results of the densification levels listed in Examples 1 to 13, Examples 14 to 25 have densification levels that are The obvious improvement is higher than 98% and up to 99.97%. It can be seen that adding the second component to the iron-platinum-based target does help to further improve the density of the iron-platinum-based target. However, although Comparative Examples 11 to 18 have the same composition as Examples 14, 15, 16, 17, 18, 20, 22, and 25, respectively, the average size of the black phase and the dispersion uniformity of Comparative Examples 11 to 18 are not In the specific scope defined by this creation, there are still serious problems such as abnormal discharge and particle falling. In addition, further referring to the groups of Comparative Examples 19 and 20, except that the average size of the black phase and the uniformity of dispersion are not within the specific range defined in this creation, the content of the second component contained in these groups is also It is not in the specific range of 2at% to 40at% further defined in this creation, so it not only has a higher abnormal discharge The number of times (109 and 117) and the number of particles dropped (1236 and 1344), the density of the iron-platinum-based targets (96.13% and 95.20%) is also significantly poorer.

To sum up, in this work, by properly controlling the boron nitride content of the iron-platinum-based target, and controlling the average size and dispersion uniformity of the black phase in the metallographic phase, the flexural strength of the iron-platinum-based target can be improved at the same time. , Reduce the probability of abnormal discharge of iron-platinum-based targets during the sputtering process and reduce the problem of particles falling on the film, thereby improving the film quality and yield of the magnetic recording layer formed by sputtering.

The above-mentioned embodiments are only examples to illustrate the present creation, and are not intended to limit the scope of the rights claimed by the present creation in any respect. The scope of rights claimed in this creation should be subject to the scope of the patent application, rather than being limited to the above-mentioned specific embodiments.

Claims (20)

An iron-platinum-based target, comprising iron, platinum and boron nitride; wherein, based on the total number of atoms of the iron-platinum-based target as a whole, the content of boron nitride is greater than 0 atomic percent and less than or equal to 50 atomic percent ; The metallographic phase of the iron-platinum-based target material includes a plurality of black phases, the average size of these black phases is less than 3 microns, and the dispersion uniformity of these black phases in the metallographic phase is less than 5 × 10 ^-4 , wherein the dispersion uniformity is It is calculated by the following formula: (total area of black phase in metallographic phase/overall area of metallographic phase)/total number of black phase in metallographic phase. The iron-platinum-based target according to claim 1, wherein, based on the total number of atoms of the whole iron-platinum-based target, the content of boron nitride is greater than or equal to 3 atomic percent and less than or equal to 30 atomic percent. The iron-platinum-based target according to claim 1, wherein, based on the total number of atoms of the whole iron-platinum-based target, the content of boron nitride is greater than or equal to 5 atomic percent and less than or equal to 25 atomic percent. The iron-platinum-based target according to claim 1, wherein, based on the total atomic number of the iron-platinum-based target as a whole, the content of platinum is greater than or equal to 10 atomic percent and less than or equal to 45 atomic percent. The iron-platinum-based target material as claimed in claim 1, wherein the iron-platinum-based target material further comprises a first component, and the first component is selected from the group consisting of oxides, carbides, nitrides and combinations thereof ; Wherein, based on the total number of atoms of the iron-platinum-based target as a whole, the content of the first component is greater than 0 atomic percent and less than or equal to 50 atomic percent, and the total content of the first component and boron nitride is greater than or equal to 6 atomic percent and less than or equal to 50 atomic percent. The iron-platinum-based target material according to claim 1, wherein the iron-platinum-based target material further comprises carbon, and based on the total number of atoms of the whole iron-platinum-based target material, the carbon content is greater than or equal to 2 atomic percent and Less than or equal to 40 atomic percent. The iron-platinum-based target according to claim 5, wherein the oxide comprises silicon dioxide, titanium dioxide, chromium oxide, tantalum pentoxide, cobalt oxide, manganese oxide, boron oxide, and oxide Hafnium, magnesium oxide, aluminum oxide, zirconium dioxide, niobium pentoxide, vanadium pentoxide, tungsten trioxide, iron oxide, zinc oxide, or combinations thereof. The iron-platinum-based target according to claim 5, wherein the nitride comprises aluminum nitride, titanium nitride, chromium nitride, zirconium nitride, tantalum nitride, hafnium nitride, silicon nitride, and carbon nitride Titanium, tungsten nitride, or a combination thereof. The iron-platinum-based target material according to claim 5, wherein the carbide comprises silicon carbide, boron carbide, titanium carbide, tungsten carbide, tantalum carbide, hafnium carbide, zirconium carbide, vanadium carbide, niobium carbide, chromium carbide or the like combination. The iron-platinum-based target material according to claim 1, wherein the iron-platinum-based target material further comprises a second component selected from the group consisting of silver, gold, germanium, copper, nickel, cobalt, aluminum, magnesium, The group consisting of manganese, silicon, strontium and their combinations; wherein, based on the total number of atoms of the iron-platinum-based target as a whole, the content of the second component is greater than or equal to 2 atomic percent and less than or equal to 40 atomic percent . The iron-platinum-based target material as claimed in claim 10, wherein the iron-platinum-based target material further comprises carbon, and based on the total number of atoms of the whole iron-platinum-based target material, the carbon content is greater than or equal to 2 atomic percent and Less than or equal to 10 atomic percent. The iron-platinum-based target material according to claim 5, wherein the iron-platinum-based target material further comprises a second component selected from the group consisting of silver, gold, germanium, copper, nickel, cobalt, aluminum, magnesium, The group consisting of manganese, silicon, strontium and their combinations; wherein, based on the total number of atoms of the iron-platinum-based target as a whole, the content of the second component is greater than or equal to 2 atomic percent and less than or equal to 40 atomic percent . The iron-platinum-based target material according to claim 12, wherein the iron-platinum-based target material further comprises carbon, and based on the total number of atoms of the whole iron-platinum-based target material, the carbon content is greater than or equal to 2 atomic percent and Less than or equal to 10 atomic percent. The iron-platinum-based target according to any one of claims 1 to 13, wherein the flexural strength of the iron-platinum-based target is greater than or equal to 700 megapascals. A method for producing an iron-platinum-based target, comprising the following steps: step (a): mixing iron raw materials, platinum raw materials and boron nitride raw materials to obtain a raw material mixture, wherein the average particle size of the boron nitride raw materials is less than 5 microns; step (b): grinding the raw material mixture for 4 hours to 12 hours, then sieving with a sieve of 800 to 1200 meshes, then taking the sieve and repeating the above-mentioned grinding and sieving steps, to obtain an iron-platinum-based mixed raw material; and step (c): sintering the iron-platinum-based mixed raw material to obtain the iron-platinum-based target; wherein, based on the total number of atoms of the whole iron-platinum-based mixed raw material, nitriding The addition amount of boron raw material is greater than 0 atomic percent and less than or equal to 50 atomic percent; the metallographic phase of the iron-platinum-based target contains a plurality of black phases, the average size of these black phases is less than 3 microns, and the dispersion of these black phases The uniformity is less than 5×10 ^-4 , wherein the dispersion uniformity is calculated by the following formula: (total area of black phases in the metallographic phase/overall area of the metallographic phase)/total number of black phases in the metallographic phase. The production method according to claim 15, wherein, based on the total number of atoms of the entire iron-platinum-based mixed raw material, the amount of platinum raw material added is greater than or equal to 10 atomic percent and less than or equal to 45 atomic percent. The production method of claim 15, wherein the iron-platinum-based mixed raw material further comprises a first component, and the first component is selected from the group consisting of oxide raw materials, carbide raw materials, nitride raw materials and combinations thereof; Wherein, based on the total number of atoms of the whole iron-platinum-based mixed raw material, the addition amount of the first component is greater than 0 atomic percent and less than or equal to 50 atomic percent, and the sum of the addition amount of the first component and the boron nitride raw material is greater than or equal to 6 atomic percent and less than or equal to 50 atomic percent. The production method according to claim 15, wherein the iron-platinum-based mixed raw material further comprises carbon raw material; wherein, based on the total number of atoms of the iron-platinum-based mixed raw material as a whole, the addition amount of the carbon raw material is greater than or equal to 2 atoms percent and less than or equal to 40 atomic percent. The method of claim 15, wherein the iron-platinum-based mixed raw material further comprises a second component, and the second component is selected from the group consisting of silver raw materials, gold raw materials, germanium raw materials, copper raw materials, nickel raw materials, cobalt raw materials, and aluminum raw materials , a group consisting of magnesium raw materials, manganese raw materials, silicon raw materials, strontium raw materials and their combinations; wherein, based on the total number of atoms of the iron-platinum-based mixed raw materials as a whole, the addition amount of the second component is greater than or equal to 2 atoms percent and less than or equal to 40 atomic percent. The production method according to claim 15, wherein, in the step (c), the sintering temperature is 600°C to 1200°C, and the sintering pressure is 350 bar to 1800 bar.

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