A CoFeB target material and preparation method thereof

Abstract

The present invention relates to the technical field of sputtering target materials, and in particular to a CoFeB target material and a preparation method thereof, wherein the preparation method comprises the following steps: (1) melting of raw material blanks; (2) secondary feeding; (3) stirring; (4) melt casting; and (5) target material preparation. The preparation method of the present invention sequentially melts the raw material blanks, performs secondary feeding, stirs, and then performs melt casting to directly obtain a CoFeB ingot with uniform structure and good performance, and then prepares the CoFeB target material through slicing, machining, welding and other processes. The obtained CoFeB target material has the advantages of high density, uniform structure, low oxygen content (≤100wtppm), etc., can meet the requirements of magnetron sputtering, and can be widely used in the preparation of magnetic heads, magnetoresistive sensors, and magnetoresistive elements (MRAM) and other fields. The preparation method of the present invention can also effectively solve the problems of poor plasticity and easy cracking caused by increased B content.

Description

Technical Field

[0001] The present invention relates to the technical field of sputtering target materials, and in particular to a CoFeB target material and a preparation method thereof. Background Art

[0002] Magnetoresistive RAM (MRAM) has the advantages of non-volatility and fast read and write speed. It is expected to replace dynamic random access memory (DRAM) and become the mainstream memory in the future. The basic storage unit of MRAM is magnetic tunnel junction (MTJ), which consists of a free layer, a tunnel gate, and a fixed layer. At present, physical vapor deposition, especially magnetron sputtering, is usually used to prepare MTJ thin film structures. By setting a strong magnetic field on the back of the target, increasing the ionization of argon gas to continuously bombard the target atoms and then deposit the coating. The raw materials used are soft magnetic material targets containing B, for example, alloys composed of elements such as Co, Fe, Ni and boron. At present, the most widely used and mature alloy composition system is CoFeB ternary alloy. Since CoFeB is a soft magnetic alloy, its magnetic field penetration ability will significantly affect the sputtering performance of the target. If the magnetic permeability is less than 2%, the coating deposition rate of the target will drop significantly, and even arcing will not occur in the early stage of sputtering.

[0003] Due to the high boron content in CoFeB alloy, especially when the boron content exceeds 30at%, the conventional melt-casting method will form coarse and brittle borides, which will cause the ingot to crack easily during the cooling process, making it almost impossible to form the material. Usually, the ingot cooling rate is reduced to prevent cracking, but due to the addition of element B, reducing the cooling rate will cause serious component segregation in the organization, which will lead to uneven distribution of alloy composition, organization, and magnetic properties, making it difficult to ensure the sputtering coating performance of the target material.

[0004] Another method to prevent cracking of CoFeB alloy is to use powder metallurgy sintering method, which can avoid cracks and segregation problems on the basis of ensuring uniform organization and composition. However, due to the large surface area of ​​powder, it is easy to adsorb gas, and it is difficult to obtain a low content of gas impurity elements, especially oxygen, which is usually 150wtppm or even higher. Therefore, the target prepared by powder metallurgy is prone to produce particles and other adverse reactions during the sputtering process. Summary of the invention

[0005] The invention provides a CoFeB target material and a preparation method thereof, which are used to solve the problems of easy cracking, high impurity content and the like in the existing preparation method of CoFeB alloy.

[0006] In a first aspect of the present invention, the present invention provides a method for preparing a CoFeB target, comprising the following steps:

[0007] (1) melting the raw material blank: melting the raw material blank containing cobalt, iron and boron until it melts to obtain a molten liquid; wherein the melting point of the raw material blank is ≤1200°C;

[0008] (2) Secondary feeding: adding a boron-containing secondary feeding powder to the molten metal obtained in step (1) at T°C, and then performing a heat preservation treatment to obtain an alloy melt; wherein the melting point of the raw material blank is ≤T°C < the melting point of the secondary feeding powder;

[0009] (3) stirring: stirring the alloy melt obtained in step (2) until the secondary feed powder is evenly distributed in the melt;

[0010] (4) melt casting: casting the alloy melt treated in step (3) to obtain a CoFeB ingot;

[0011] (5) Target preparation: A CoFeB target is prepared using the CoFeB ingot obtained in step (4).

[0012] Figure 1 The Co-Fe-B ternary phase diagram is shown, where the dotted area is the (Co, Fe)2B first precipitated phase area with alloy composition melting point ≤ 1200℃. When the CoFeB ingot with boron content greater than 30at% is prepared by conventional smelting method, the ingot microstructure phase composition is the first precipitation of primary (Co, Fe)B phase and the eutectic structure composed of (Co, Fe)B phase and (Co, Fe)2B phase (see Figure 1 ), since both phases are hard and brittle phases with poor plasticity, the ingot is very easy to crack during cooling and is difficult to form. The core idea of ​​the present invention is to split the high-boron ingot composition into two parts: the low-boron parent phase component (i.e., the raw material blank) and the secondary feed powder component, and adjust the parent phase component to the (Co, Fe)2B first precipitation phase region (such as Figure 1Indicated by the dotted box). There are two advantages to regulating the matrix composition to this region: 1. When the matrix composition is within this region, the melting point is ≤1200°C, which can ensure that the high-melting-point secondary feed powder does not melt when the matrix composition is completely melted; 2. When the matrix composition is within this region, the eutectic structure finally formed will contain fcc-Fe phase or bcc-Fe phase with good plasticity to coordinate the stress-strain behavior during the cooling process, thereby improving the plastic forming performance of the alloy. At the same time, the present invention introduces a large number of nucleation particles of the first precipitated primary phase into the melt by adding the secondary feed powder through the secondary feed method, increases the number of nucleations of the first precipitated primary phase, and then plays a role in regulating the morphology, quantity and distribution of the first precipitated primary phase, and regulates the coarse and unevenly distributed first precipitated primary phase into a fine, uniform and dispersed first precipitated primary phase. The preparation method of the present invention sequentially melts the raw material blank, feeds the material twice, stirs it, and then performs melt casting to directly obtain a CoFeB ingot with uniform structure and good performance, and then prepares the CoFeB target material through slicing, machining, welding and other processes. The obtained CoFeB target material has the advantages of high density, uniform structure, low oxygen content (≤100wtppm), etc., and can meet the requirements of magnetron sputtering. The preparation method of the present invention can effectively solve the problems of poor plasticity and easy cracking caused by increased B content.

[0013] In a possible design, in step (2), the atomic ratio of Fe to B in the secondary feed powder is (1-2):1.

[0014] Optionally, the atomic ratio of Fe to B in the secondary feed powder can be 1:1 or 1:2, etc. It can be understood that limiting the atomic ratio of Fe to B to (1-2):1 can make the secondary feed powder have a higher melting point, which can effectively prevent the secondary feed powder from dissolving in the melt and losing the function of increasing nucleation points. For example: the melting point of FeB alloy is 1398°C, and the melting point of Fe2B alloy is 1625°C).

[0015] In a possible design, in step (1), the boron content in the raw material blank is 18 at%-27.5 at%.

[0016] It can be understood that by limiting the boron content in the raw material blank in step (1) to 18at%-27.5at%, it can be effectively ensured that the melting point of the raw material blank is ≤1200°C.

[0017] In a possible design, the secondary feed powder contains one or both of iron-boron compounds and cobalt-boron compounds; in the step (2), the secondary feed powder is prepared by atomization powder making technology.

[0018] The secondary feed powder includes an iron-boron compound or a cobalt-boron compound, which can be selected according to the final composition of the alloy. It can be understood that the secondary feed powder prepared by the atomization powder making technology is more uniform and fine, which is more conducive to its subsequent uniform distribution in the melt.

[0019] In a possible design, an inert gas is used for protection during the atomization powder making process.

[0020] Optionally, the inert gas may be helium, neon, argon, krypton or xenon, etc. It is understandable that due to the high melting point of the boride, an inert gas protection is required during the atomization powder making process to avoid oxidation.

[0021] In a possible design, in step (2), 1200°C ≤ T°C ≤ 1300°C. Preferably, T°C is 1250°C.

[0022] It can be understood that by controlling T℃ between 1200℃ and 1300℃, the high-melting-point secondary feed powder can be kept from melting while the raw material billet is completely melted, thereby introducing a large number of nucleation particles that precipitate the primary phase into the melt.

[0023] In a possible design, in step (3), the stirring is performed by electromagnetic stirring; the temperature of the electromagnetic stirring is 1200° C.-1300° C., preferably 1250° C. Specifically, alternating current is used during the electromagnetic stirring process.

[0024] It can be understood that in order to ensure the uniform distribution of the secondary feed powder in the melt, electromagnetic stirring technology is used to introduce shear force into the molten metal to form a shear flow in the molten metal to achieve uniform distribution of nucleation particles. At the same time, electromagnetic stirring can also improve the temperature uniformity of the molten metal, reduce the temperature gradient on the surface and core of the ingot, and reduce macrosegregation during solidification. Furthermore, by limiting the temperature of electromagnetic stirring to 1200℃-1300℃, it can be ensured that the high-melting-point secondary feed powder does not melt when the raw material billet is completely melted.

[0025] In a possible design, in step (4), the alloy melt processed in step (3) is poured into a mold cavity for casting; the mold may be an alloy cast iron crucible, a stainless steel crucible, a graphite crucible, etc. Preferably, the mold is a graphite crucible.

[0026] It can be understood that the use of a graphite crucible can prevent stress cracking of the ingot caused by excessive temperature difference between the surface and the core of the ingot due to excessive cooling rate.

[0027] In a possible design, in the step (5), based on the CoFeB ingot, a CoFeB target blank is obtained by slicing and machining, and then it is determined whether a back plate needs to be welded according to needs; if a back plate needs to be welded, In solder is used for brazing; the material of the back plate is selected from oxygen-free copper, copper alloy, aluminum or aluminum alloy.

[0028] In a second aspect of the present invention, the present invention further provides a CoFeB target material, which is prepared by the above-mentioned preparation method; the magnetic permeability of the CoFeB target material is ≥9%; and the O content in the CoFeB target material is ≤100wtppm.

[0029] The CoFeB target material of the present invention has uniform microstructure distribution, high magnetic permeability, and low content of gas impurity elements, and can meet the client's magnetron sputtering performance requirements.

[0030] In a possible design, the B content of the CoFeB target is ≥20at%; in the CoFeB target, the Al content is ≤22wtppm, the Cu content is ≤11wtppm, the Si content is ≤58wtppm, the C content is ≤80wtppm, the O content is ≤81wtppm, and the N content is ≤45wtppm.

[0031] The present invention provides a method for preparing a CoFeB target material, wherein a CoFeB ingot with uniform structure and good performance is directly obtained by melt casting after melting raw material blanks, secondary feeding, stirring, and subsequent slicing, machining, welding and other processes to prepare a CoFeB target material. The obtained CoFeB target material has the advantages of high density, uniform structure, low oxygen content (≤100wtppm), etc., can meet the requirements of magnetron sputtering, and can be widely used in the preparation of magnetic heads, magnetoresistive sensors, and magnetoresistive elements (MRAM) and other fields. The preparation method of the present invention can also effectively solve the problems of poor plasticity and easy cracking caused by increased B content, and can prepare a high-boron (B≥30at%) CoFeB target material with excellent performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0033] Figure 1 It is the Co-Fe-B ternary phase diagram provided by the present invention;

[0034] Figure 2 It is a process flow chart of a method for preparing a CoFeB target material provided by the present invention. DETAILED DESCRIPTION

[0035] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0036] In the following embodiments and comparative examples, in the test method for the impurity content of the target material, metal elements are detected by GDMS, and gas elements are detected by LECO.

[0037] Embodiment 1:

[0038] In this example, the alloy composition is Co 35 Fe 35 B 30 The high boron alloy target is the target, and the preparation method flow chart is as follows Figure 2 As shown, the following steps are included:

[0039] Step (1) melting of raw material blanks: pickling the iron sheet and the cobalt sheet, ultrasonic cleaning and drying, weighing 142.1 g of cobalt sheet, 25.9 g of iron sheet and 12 g of boron block, and then placing them in a refractory crucible for vacuum induction melting. The composition (atomic ratio) of the CoFeB master alloy under this ratio is Co: 60.8 Fe 11.7 B 27.5 , its melting point is below 1200℃, and it can be completely melted by vacuum induction at 1200℃. After the raw material billet is completely melted, the melt temperature is controlled at about 1250℃.

[0040] Step (2) Preparation of secondary feed powder: According to the ratio of Fe: B atoms = 2: 1, secondary feed powder is obtained by atomization powder making, and 120 g is weighed. Secondary feeding: Under the premise of ensuring that the raw material blank is completely melted and the melt temperature is stable at ≤ 1300°C, the obtained secondary feed powder is added to the melt of step (1) through the secondary feeding system, followed by 20 minutes of heat preservation treatment to obtain an alloy melt.

[0041] Step (3) electromagnetic stirring: the alloy melt obtained in step (2) is transferred to a 1250° C. holding furnace, and an alternating current is passed through the coil for electromagnetic stirring until the secondary feed powder is evenly distributed in the melt.

[0042] Step (4) melt casting: pouring the alloy melt treated in step (3) into the graphite mold cavity to obtain a uniform and crack-free Co 35 Fe 35 B30 Ingot.

[0043] Step (5) Target preparation: CoFeB target blank is obtained by slicing and machining, and the initial CoFeB target blank is obtained by wire cutting slicing, followed by precision size processing. Finally, In solder and oxygen-free copper backing plate are used for brazing to obtain a high-boron CoFeB alloy target that meets the sputtering requirements.

[0044] As shown in Table 1, the impurity content (wt) of the target material in Example 1 is as follows: Al-22 ppm, Cu-10 ppm, Si-43 ppm, C-80 ppm, O-75 ppm, N-30 ppm.

[0045] Example 2

[0046] In this example, the alloy composition is Co 25 Fe 40 B 35 The high boron alloy target is taken as the target, and the preparation method comprises the following steps:

[0047] Step (1) melting of raw material blanks: pickling the iron sheet and the cobalt sheet, ultrasonic cleaning and drying, weighing 179.7 g of cobalt sheet, 139.6 g of iron sheet and 20.7 g of boron block, and then placing them in a refractory crucible for vacuum induction melting. The composition (atomic ratio) of the CoFeB master alloy under this ratio is Co: 41 Fe 33.6 B 25.4 Its melting point is below 1200℃, and it can be completely melted by vacuum induction at 1200℃. After the raw material billet is completely melted, the melt temperature is controlled below 1250℃.

[0048] Step (2) Preparation of secondary feed powder: According to the atomic ratio of Fe: B = 1:1, secondary feed powder is obtained by gas atomization powder making, and 160g is weighed. Secondary feeding: Under the premise of ensuring that the raw material blank is completely melted and the melt temperature is stable ≤ 1300°C, the obtained secondary feed powder is added to the melt of step (1) through the secondary feeding system, and then the alloy melt is kept warm for 30 minutes to obtain an alloy melt.

[0049] Step 3) Electromagnetic stirring: The alloy melt obtained in step (2) is transferred to a 1250° C. holding furnace, and an alternating current is passed through the coil for electromagnetic stirring until the secondary feed powder is evenly distributed in the melt.

[0050] Step 4) melt casting: pour the alloy melt treated in step (3) into the mold cavity to obtain a uniform and crack-free Co 25 Fe 40 B 35 Ingot.

[0051] Step 5) Target preparation: CoFeB target blank is obtained by slicing and machining. The initial CoFeB target blank is obtained by wire cutting slicing, followed by precision size processing. Finally, In solder and oxygen-free copper backing plate are brazed to obtain a high-boron CoFeB alloy target that meets sputtering requirements.

[0052] As shown in Table 1, the impurity content (wt) of the target material in Example 2 is as follows: Al-18ppm, Cu-8ppm, Si-58ppm, C-77ppm, O-81ppm, N-45ppm.

[0053] Example 3

[0054] In this example, the alloy composition is Co 20 Fe 60 B 20 The alloy target is the target, and the preparation method comprises the following steps:

[0055] Step (1) melting of raw material blanks: pickling the iron sheet and the cobalt sheet, ultrasonic cleaning and drying, weighing 123.8 g of cobalt sheet, 303 g of iron sheet and 18.2 g of boron block, and then placing them in a refractory crucible for vacuum induction melting. The composition (atomic ratio) of the CoFeB master alloy is Co: 23 Fe 59 B 18 Its melting point is below 1200℃, and it can be completely melted by vacuum induction at 1200℃. After the raw material billet is completely melted, the melt temperature is controlled below 1250℃.

[0056] Step (2) Preparation of secondary feed powder: According to the atomic ratio of Fe: B = 2: 1, secondary feed powder is obtained by gas atomization powder making, and 55 g is weighed. Secondary feeding: Under the premise of ensuring that the raw material blank is completely melted and the melt temperature is stable ≤ 1300°C, the obtained secondary feed powder is added to the melt of step (1) through the secondary feeding system, and then the alloy melt is kept warm for 15 minutes to obtain an alloy melt.

[0057] Step (3) electromagnetic stirring: the alloy melt obtained in step 2) is transferred to a 1250° C. holding furnace, and an alternating current is passed through the coil for electromagnetic stirring until the secondary feed powder is evenly distributed in the melt.

[0058] Step (4) melt casting: pouring the alloy melt treated in step (3) into the graphite mold cavity to obtain a uniform and crack-free Co 20 Fe 60 B 20 Ingot.

[0059] Step (5) Target material preparation: CoFeB target blank is obtained by slicing and machining. The initial CoFeB target blank is obtained by wire cutting slicing, followed by precision sizing. Finally, In solder and oxygen-free copper backing plate are used for brazing to obtain a high-boron CoFeB alloy target that meets sputtering requirements.

[0060] As shown in Table 3, the magnetic permeability of Example 3 is 9%, which meets the requirements for arc starting of magnetron sputtering.

[0061] Comparative Example 1:

[0062] Co 35 Fe 35 B 30 The alloy components were directly subjected to gas atomization powder making, 300g of powder with a particle size of ≤200μm was screened, and a sintering treatment was carried out at 1250℃ for 5h to obtain a cobalt-iron-boron alloy target blank, and the target blank was not cracked. As shown in Table 1, the impurity content (wt) of the target material obtained in Comparative Example 1 is as follows: Al-50ppm, Cu-33ppm, Si-64ppm, C-140ppm, O-120ppm, N-80ppm. It can be seen that the purity of the target material in Comparative Example 1 is lower than that in Example 1, and the gas element content is significantly increased, which will cause the target material to have more particles during magnetron sputtering, reducing the film performance.

[0063] Comparative Example 2:

[0064] Cobalt, iron powder and boron block are used to make powder by mechanical crushing. 35 Fe 35 B 30 The alloy composition ratio, 300g of powder with a particle size of ≤200μm was screened, and a cobalt-iron-boron alloy target blank was obtained by sintering at 1100℃-3h, and the target blank was not cracked. As shown in Table 1, the impurity content (wt) of the target obtained in Comparative Example 2 is as follows: Al-44ppm, Cu-35ppm, Si-78ppm, C-162ppm, O-134ppm, N-99ppm.

[0065] Table 1 Comparison of impurity contents of the targets obtained in the examples and comparative examples

[0066]

[0067] Unit: wtppm

[0068] As shown in Table 1, by comparing Example 1, Example 2 with Comparative Example 1, Comparative Example 2, it can be seen that the preparation method of the present invention is beneficial to controlling the content of impurity elements, especially the content of gas elements such as oxygen and nitrogen, and can effectively reduce the number of particles appearing during the sputtering process of the target.

[0069] Comparative Example 3:

[0070] Co 35 Fe 35 B 30 The target material composition is made up of the following raw material ratios: 142.1g of cobalt sheet, 135.1g of iron sheet, and 22.8g of boron block. Vacuum induction melting is carried out directly. After being completely melted, it is cast into a graphite mold. When it is taken out of the furnace, it is found that the target material is cracked and cannot be formed.

[0071] Comparative Example 4:

[0072] Co 25 Fe 40 B 35 The target material composition is made up of the following raw material ratios: 179.7g cobalt sheet, 273.3g iron sheet, and 47g boron block. Vacuum induction melting is carried out directly. After being completely melted, it is cast into a graphite mold. When it is taken out of the furnace, it is found that the target material is cracked and cannot be formed.

[0073] Table 2 Comparison of the forming properties of the targets obtained in the examples and comparative examples

[0074]

[0075] As shown in Table 2, by comparing Example 1, Example 2 with Comparative Example 3, Comparative Example 4, it can be seen that the preparation method of the present invention can achieve the forming preparation of CoFeB alloy with high boron content, which can greatly improve the yield rate and improve production efficiency.

[0076] Comparative Example 5:

[0077] Co 20 Fe 60 B 20 The target material composition is made up of the following raw material ratios: 123.8g of cobalt sheet, 353.1g of iron sheet, and 23.1g of boron block. Vacuum induction melting is carried out directly, and after being completely melted, it is directly cast into a graphite mold. No cracking of the target material is found when it is taken out of the furnace, but the magnetic permeability is only 2%, and the target material is not easy to arc during magnetron sputtering.

[0078] Table 3 Magnetic permeability of the target obtained in Example 3 and Comparative Example 5

[0079]

[0080]

[0081] By comparing the results of Example 3 with those of Comparative Example 5, as shown in Table 3, it can be seen that the preparation method of the CoFeB target material provided by the present invention can effectively improve the uniformity of the structure, enhance the magnetic properties of the target material, and the prepared target material has excellent magnetron sputtering performance.

[0082] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for preparing a CoFeB target, characterized in that: The steps include: (1) Melting of raw material blanks: melting raw material blanks containing cobalt, iron and boron until they are melted to obtain a molten liquid; the melting point of the raw material blanks is ≤1200°C; (2) Secondary feeding: adding a boron-containing secondary feeding powder to the molten metal obtained in step (1) at T°C, and then performing a heat preservation treatment to obtain an alloy melt; wherein the melting point of the raw material blank is ≤T°C < the melting point of the secondary feeding powder; (3) stirring: stirring the alloy melt obtained in step (2) until the secondary feed powder is evenly distributed in the melt; (4) melt casting: casting the alloy melt treated in step (3) to obtain a CoFeB ingot; (5) Target material preparation: A CoFeB target material is prepared using the CoFeB ingot obtained in step (4).

2. The preparation method according to claim 1, characterized in that: In the step (2), the atomic ratio of Fe to B in the secondary feed powder is (1-2):

1.

3. The preparation method according to claim 1 or 2, characterized in that: In the step (2), the secondary feed powder contains one or both of iron-boron compounds and cobalt-boron compounds; the secondary feed powder is prepared by atomization powder making technology.

4. The preparation method according to claim 3, characterized in that: Inert gas is used for protection during the atomization powder making process.

5. The preparation method according to claim 1, characterized in that: In the step (1), 1200°C ≤ T°C ≤ 1300°C.

6. The preparation method according to claim 1, characterized in that: In the step (3), the stirring is performed by electromagnetic stirring; the temperature of the electromagnetic stirring is 1200°C-1300°C.

7. The preparation method according to claim 1, characterized in that: The step (4) is to pour the alloy melt processed in the step (3) into a mold cavity for casting.

8. The preparation method according to claim 7, characterized in that: The mold adopts a graphite crucible.

9. The preparation method according to claim 1, characterized in that: In the step (5), on the basis of obtaining the CoFeB ingot, a CoFeB target blank is obtained by slicing and machining, and then it is determined whether a back plate needs to be welded according to needs; if a back plate needs to be welded, In solder is used for brazing; the material of the back plate is selected from oxygen-free copper, copper alloy, aluminum or aluminum alloy.

10. A CoFeB target material, characterized in that: The target is prepared by the preparation method according to any one of claims 1 to 9; the magnetic permeability of the CoFeB target is ≥ 9%; and the O content in the CoFeB target is ≤ 100wtppm.

11. The CoFeB target material according to claim 10, characterized in that: The B content of the CoFeB target is ≥20at%; in the CoFeB target, the Al content is ≤22wtppm, the Cu content is ≤11wtppm, the Si content is ≤58wtppm, the C content is ≤80wtppm, the O content is ≤81wtppm, and the N content is ≤45wtppm.

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