Preparation method of CoZrTaB sputtering target material

Abstract

The invention relates to a preparation method of a CoZrTaB sputtering target material, which comprises the following steps: (1) carrying out first vacuum suspension smelting on a Co raw material and a Ta raw material according to the ratio of Co to Ta in the target material to obtain a CoTa intermediate alloy; (2) the ZrB2 alloy powder is subjected to compression molding and vacuum sintering in sequence, and a ZrB2 alloy blank is obtained; (3) proportioning the CoTa intermediate alloy obtained in the step (1) and the ZrB2 alloy blank obtained in the step (2) according to component requirements of a target material, and then carrying out second vacuum suspension smelting to obtain a CoZrTaB multi-component alloy melt; and (4) the CoZrTaB multi-element alloy melt obtained in the step (3) is subjected to casting molding, and the CoZrTaB sputtering target material is obtained. According to the preparation method provided by the invention, the problem of distribution uniformity of high-melting-point Ta and a light element B is solved, and the CoZrTaB target material which is uniform in component, compact in structure and excellent in performance is obtained.

Description

Technical Field

[0001] This invention relates to the field of sputtering target technology, and specifically to a method for preparing a CoZrTaB sputtering target. Background Technology

[0002] With the rapid development of semiconductor and magnetic storage technologies, high-performance magnetic thin film materials are increasingly widely used in information storage, sensors, and microelectronic devices. As a key material for preparing high-quality magnetic thin films, the performance of magnetic alloy targets directly affects the quality of the film and the performance of the device. Among them, CoZrTaB multi-element alloy targets have significant application value in magnetic recording heads and microwave devices due to their excellent soft magnetic properties and high-frequency characteristics.

[0003] CN113235058A discloses a method for preparing a CoZrTa alloy target billet and target material, including the following steps: (1) Weigh the required raw materials according to the ratio. The raw materials include Co flakes, Ta flakes and Zr particles. They are stacked in layers, with the bottom and top layers being Co flakes. The middle Ta flake layer and Zr particle layer cannot be adjacent layers. The raw materials are placed in a water-cooled copper crucible; (2) After evacuating the crucible, the power is increased. When it is observed that there are no insoluble substances rolling in the melt, the power is kept stable. After magnetic levitation melting, the melt is kept at a constant temperature to obtain the melt; (3) The melt obtained in step (2) is cast into a mold for molding. After initial processing and rolling, the CoZrTa alloy is obtained. Although this method prepares a CoZrTa alloy target billet, it does not involve the addition of element B. As a light element, element B is easily oxidized and burned off during the melting process, resulting in a large difference between the actual amount added and the effective B content in the final alloy, which is difficult to control precisely.

[0004] CN117259476A discloses a method for preparing a large-size, fine-grained CoZrTa alloy target blank, comprising the following steps: (1) vacuum melting of Co, Zr, and Ta raw materials, casting to obtain a blank; (2) extruding the blank; (3) after extrusion molding, allowing the blank to cool naturally to room temperature; (4) hot rolling and leveling the blank; (5) cooling the blank to room temperature; (6) surface processing of the blank to obtain the target blank. This method can prepare a large-size, fine-grained CoZrTa target blank, but it also does not add B element and has insufficient control over the uniformity of alloy composition.

[0005] Currently, the preparation of existing CoZrTaB multi-element alloy targets has the following problems: (1) Light element B is easily oxidized and volatilized during the melting process, resulting in an actual yield that is far lower than the design value and poor composition control accuracy; (2) The melting point of elemental Ta is much higher than that of other elements, and conventional melting conditions make it difficult to fully dissolve and uniformly distribute it. Extremely high melting temperatures (far exceeding the melting point of Co) are required to ensure that Ta is completely dissolved; (3) The corrosive effect of high-temperature melt on crucible will cause impurity elements in the crucible to enter the melt, causing pollution. This not only reduces the purity of the alloy, but also significantly shortens the service life of the crucible and increases production costs; (4) It is difficult to guarantee the compositional uniformity and microstructure density of the target material, which seriously affects the performance and reliability of the target material.

[0006] Therefore, providing a method for preparing a CoZrTaB sputtering target is a technical problem that needs to be solved in this field. Summary of the Invention

[0007] To address the above problems, the present invention aims to provide a method for preparing CoZrTaB sputtering targets. Compared with the prior art, the preparation method provided by the present invention solves the problem of uniform distribution of high melting point Ta and light element B, and obtains CoZrTaB targets with uniform composition, dense structure and excellent performance.

[0008] To achieve this objective, the present invention adopts the following technical solution:

[0009] This invention provides a method for preparing a CoZrTaB sputtering target, the method comprising the following steps:

[0010] (1) According to the ratio of Co and Ta in the target material, the Co raw material and the Ta raw material are subjected to the first vacuum suspension melting to obtain the CoTa intermediate alloy.

[0011] (2) ZrB2 alloy powder is pressed and vacuum sintered in sequence to obtain ZrB2 alloy billet;

[0012] (3) The CoTa intermediate alloy obtained in step (1) and the ZrB2 alloy billet obtained in step (2) are prepared according to the composition requirements of the target material, and then a second vacuum suspension melting is carried out to obtain CoZrTaB multi-element alloy melt.

[0013] (4) The CoZrTaB multi-element alloy melt obtained in step (3) is cast into a CoZrTaB sputtering target.

[0014] In this invention, Co and Ta are pre-prepared into a CoTa master alloy, which effectively reduces the temperature requirement during the melting process. The melting point of the CoTa master alloy is lower than the temperature required to melt Ta alone, ensuring that the Ta element can be fully dissolved and uniformly distributed during the melting process. In the subsequent melting process, the CoTa master alloy is mixed and melted with the ZrB2 alloy billet, which further promotes the uniform distribution of each element, and finally a CoZrTaB multi-element alloy melt with uniform composition is obtained.

[0015] Preferably, the purity of the Co raw material in step (1) is ≥4N, for example, it can be 99.99%, 99.991%, 99.992%, 99.993%, 99.994% or 99.995%, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0016] Preferably, the purity of the Ta raw material is ≥4N, for example, it can be 99.99%, 99.991%, 99.992%, 99.993%, 99.994% or 99.995%, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0017] Preferably, step (1) the first vacuum suspension melting includes: placing Co raw material and Ta raw material alternately in a crucible in layers, then evacuating the melting furnace and filling it with argon gas in sequence, and then performing suspension melting.

[0018] In this invention, the alternating layering of Co and Ta helps to achieve more uniform mixing during the smelting process and avoids localized aggregation of high-melting-point Ta elements.

[0019] Preferably, the vacuum degree after vacuuming in the first vacuum suspension melting process is 4.0 × 10⁻⁶. -3 -6.0×10 -3 Pa, for example, could be 4.0 × 10 -3 Pa, 4.5 × 10 -3 Pa, 5×10 -3 Pa, 5.5 × 10 -3 Pa or 6×10 -3 Pa, but not limited to the listed values, applies to other unlisted values ​​within the range as well.

[0020] Preferably, the furnace pressure after argon gas is introduced in the first vacuum suspension melting is 0.06-0.10 MPa, for example, it can be 0.06 MPa, 0.07 MPa, 0.08 MPa, 0.09 MPa or 0.10 MPa, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0021] Preferably, the temperature of the suspension melting in the first vacuum suspension melting is 1800-2200℃, for example, it can be 1800℃, 1820℃, 1840℃, 1860℃, 1880℃, 1900℃, 1920℃, 1940℃, 1960℃, 1980℃, 2000℃, 2020℃, 2040℃, 2060℃, 2080℃, 2100℃, 2120℃, 2140℃, 2160℃, 2180℃ or 2200℃, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0022] Preferably, the number of suspension melting processes in the first vacuum suspension melting is 3-5 times, for example, 3 times, 4 times or 5 times.

[0023] In this invention, by controlling the number of suspension melting processes, the melt can be thoroughly stirred and mixed, reducing local agglomeration and segregation. In this invention, the ingot is flipped over after each melting process to ensure complete alloying of the raw materials.

[0024] Preferably, the purity of the ZrB2 alloy powder in step (2) is ≥3N, for example, it can be 99.9%, 99.91%, 99.92%, 99.93%, 99.94% or 99.95%, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0025] Preferably, the average particle size of the ZrB2 alloy powder is 10-30 μm, for example, it can be 10 μm, 12 μm, 14 μm, 16 μm, 18 μm, 20 μm, 22 μm, 24 μm, 26 μm, 28 μm or 30 μm, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0026] Preferably, the pressing pressure in step (2) is 100-200 MPa, for example, it can be 100 MPa, 110 MPa, 120 MPa, 130 MPa, 140 MPa, 150 MPa, 160 MPa, 170 MPa, 180 MPa, 190 MPa or 200 MPa, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0027] Preferably, the vacuum sintering temperature in step (2) is 1000-1200℃, for example, it can be 1000℃, 1010℃, 1020℃, 1030℃, 1040℃, 1050℃, 1060℃, 1070℃, 1080℃, 1090℃, 1100℃, 1110℃, 1120℃, 1130℃, 1140℃, 1150℃, 1160℃, 1170℃, 1180℃, 1190℃ or 1200℃, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0028] Preferably, the vacuum sintering time is 1-2 hours, for example, it can be 1 hour, 1.2 hours, 1.4 hours, 1.6 hours, 1.8 hours or 2 hours, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0029] In this invention, ZrB2 powder can be formed into a blank with a certain density and strength through pressing and sintering processes. The dense ZrB2 blank can be better mixed with the CoTa master alloy in the subsequent melting process, reducing the introduction of pores and impurities, thereby improving the density of the final alloy. The sintered blank can melt more uniformly during melting, reducing local agglomeration, thereby improving the overall uniformity of the alloy.

[0030] Preferably, step (3) the second vacuum suspension melting includes: stacking CoTa master alloy and ZrB2 alloy billet alternately in a crucible, then evacuating and filling the melting furnace with argon gas, and then performing suspension melting.

[0031] Preferably, the vacuum degree after vacuuming in the second vacuum suspension melting process is 4.0 × 10⁻⁶. -3 -6.0×10 -3 Pa, for example, could be 4.0 × 10 -3 Pa, 4.5 × 10 -3 Pa, 5×10 -3 Pa, 5.5 × 10 -3 Pa or 6×10 -3 Pa, but not limited to the listed values, applies to other unlisted values ​​within the range as well.

[0032] Preferably, the furnace pressure after argon is introduced in the second vacuum suspension melting is 0.06-0.10 MPa, for example, it can be 0.06 MPa, 0.07 MPa, 0.08 MPa, 0.09 MPa or 0.10 MPa, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0033] Preferably, the temperature of the suspension melting in the second vacuum suspension melting is 1900-2300℃, for example, it can be 1900℃, 1920℃, 1940℃, 1960℃, 1980℃, 2000℃, 2020℃, 2040℃, 2060℃, 2080℃, 2100℃, 2120℃, 2140℃, 2160℃, 2180℃, 2200℃, 2220℃, 2240℃, 2260℃, 2280℃ or 2300℃, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0034] In this invention, by optimally controlling the temperature of the suspension melting in the second vacuum suspension melting, it is possible to ensure that the raw materials are fully dissolved, thereby improving the uniformity of the alloy, while reducing element loss and ensuring the accuracy of the alloy composition.

[0035] Preferably, the number of suspension melting processes in the second vacuum suspension melting is 3-5 times, for example, 3 times, 4 times or 5 times.

[0036] In this invention, by controlling the number of suspension melting processes, the melt can be thoroughly stirred and mixed, reducing local agglomeration and segregation. In this invention, the ingot is flipped over after each melting process to ensure complete alloying of the raw materials.

[0037] In this invention, the problem of insufficient alloying in traditional smelting methods is solved by repeatedly performing suspension smelting and flipping the ingot over after each smelting process.

[0038] Preferably, the mold is preheated before casting in step (4).

[0039] Preferably, the preheating temperature is 500-800℃, for example, it can be 500℃, 550℃, 600℃, 650℃, 700℃, 750℃ or 800℃, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0040] In this invention, preheating the mold allows for better filling of the molten metal, reduces surface defects in the casting, minimizes thermal stress, and prevents cracking of the target blank. The mold is typically a graphite mold.

[0041] Preferably, after casting in step (4), the material is further finished.

[0042] Preferably, the finishing process includes sawing, turning, milling, grinding, and polishing performed sequentially.

[0043] Preferably, the flatness of the finished CoZrTaB sputtering target is ≤0.05mm, for example, it can be 0.05mm, 0.04mm, 0.03mm, 0.02mm or 0.01mm, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0044] As a preferred embodiment of the present invention, the preparation method includes the following steps:

[0045] (1) According to the ratio of Co and Ta in the target material, Co raw material with a purity ≥4N and Ta raw material with a purity ≥4N are subjected to a first vacuum suspension melting, including: placing the Co raw material and Ta raw material alternately in layers in a crucible, and then evacuating the melting furnace to a vacuum degree of 4.0×10⁻⁶. -3 -6.0×10 -3 Pa, then argon gas is introduced into the furnace to a pressure of 0.06-0.10 MPa, and then suspension melting is carried out at a temperature of 1800-2200℃. The suspension melting is carried out 3-5 times to obtain a CoTa master alloy.

[0046] (2) ZrB2 alloy powder with a purity ≥3N (average particle size of 10-30μm) is pressed into shape under a pressure of 100-200MPa, and then vacuum sintered at a temperature of 1000-1200℃ for 1-2h to obtain ZrB2 alloy billet.

[0047] (3) The CoTa master alloy obtained in step (1) and the ZrB2 alloy billet obtained in step (2) are batched according to the target material composition requirements, and then a second vacuum suspension melting is performed, including: the CoTa master alloy and the ZrB2 alloy billet are stacked alternately in a crucible, and then the melting furnace is evacuated to a vacuum degree of 4.0 × 10⁻⁶. -3 -6.0×10 -3 Pa, then argon gas is introduced into the furnace to a pressure of 0.06-0.10 MPa, and then suspension melting is carried out at a temperature of 1900-2300℃. The suspension melting is carried out 3-5 times to obtain CoZrTaB multi-element alloy melt;

[0048] (4) The CoZrTaB multi-element alloy melt obtained in step (3) is cast into a mold. Before casting, the mold is preheated to 500-800℃, and then sawing, turning, milling, grinding and polishing are performed in sequence to obtain CoZrTaB sputtering target. The flatness of the CoZrTaB sputtering target after finishing is ≤0.05mm.

[0049] Compared with the prior art, the present invention has the following beneficial effects:

[0050] (1) The preparation method provided by the present invention, by pre-preparing a CoTa master alloy and a ZrB2 alloy billet, and then preparing a CoZrTaB sputtering target, can significantly improve the uniformity of the target composition compared with the traditional method of directly melting the elemental materials in one step. Under preferred conditions, the present invention can reduce the segregation degree of Co to below 0.9%, the segregation degree of Zr to below 0.9%, the segregation degree of Ta to below 0.9%, and the segregation degree of B to below 0.6%.

[0051] (2) The preparation method provided by the present invention reduces the introduction of impurities by using suspension melting, further promotes the uniformity of alloy composition by magnetic field force, and effectively controls the composition and structure of the target material by casting molding, thereby obtaining a CoZrTaB sputtering target material with stable performance.

[0052] (3) The preparation method provided by the present invention is simple, convenient to operate, has good repeatability and stability, is suitable for large-scale industrial production, and can effectively meet the strict requirements of high-end electronic device manufacturing for high-performance CoZrTaB sputtering targets. Detailed Implementation

[0053] The technical solution of the present invention will be further illustrated below through specific embodiments. Those skilled in the art should understand that the embodiments described are merely illustrative of the present invention and should not be construed as limiting the invention in any way.

[0054] Example 1

[0055] This embodiment provides a method for preparing a CoZrTaB sputtering target, the method comprising the following steps:

[0056] (1) According to the ratio of Co and Ta in the target material, a Co block with a purity of 4N and a Ta block with a purity of 4N are subjected to a first vacuum suspension melting process, including: placing the Co block and Ta block alternately in a crucible in layers, and then evacuating the melting furnace to a vacuum degree of 4.0 × 10⁻⁶. -3 Pa, then argon gas is introduced into the furnace to a pressure of 0.06 MPa, and then suspension melting is carried out at a temperature of 2000℃. The suspension melting is carried out 4 times to obtain a CoTa master alloy.

[0057] (2) ZrB2 alloy powder with a purity of 3N (average particle size of 20μm) was pressed into shape under a pressure of 150MPa and then vacuum sintered at a temperature of 1100℃ for 1.5h to obtain ZrB2 alloy billet.

[0058] (3) The CoTa master alloy obtained in step (1) and the ZrB2 alloy billet obtained in step (2) are batched according to the target material composition requirements, and then a second vacuum suspension melting is performed, including: the CoTa master alloy and the ZrB2 alloy billet are stacked alternately in a crucible, and then the melting furnace is evacuated to a vacuum degree of 4.0 × 10⁻⁶. -3 Pa, then argon gas is introduced into the furnace to a pressure of 0.06 MPa, and then suspension melting is carried out at a temperature of 2100℃. The suspension melting is carried out 4 times to obtain CoZrTaB multi-element alloy melt;

[0059] (4) The CoZrTaB multi-element alloy melt obtained in step (3) is cast into a mold. Before casting, the graphite mold is preheated to 600°C, and then sawing, turning, milling, grinding and polishing are performed in sequence to obtain the CoZrTaB sputtering target. The flatness of the CoZrTaB sputtering target after finishing is 0.04 mm.

[0060] Example 2

[0061] This embodiment provides a method for preparing a CoZrTaB sputtering target, the method comprising the following steps:

[0062] (1) According to the ratio of Co and Ta in the target material, a Co block with a purity of 4N and a Ta block with a purity of 4N are subjected to a first vacuum suspension melting process, including: placing the Co block and Ta block alternately in a crucible in layers, and then evacuating the melting furnace to a vacuum degree of 5.0 × 10⁻⁶. -3 Pa, then argon gas is introduced into the furnace to a pressure of 0.08 MPa, and then suspension melting is carried out at a temperature of 1800℃. The suspension melting is carried out 5 times to obtain a CoTa master alloy.

[0063] (2) ZrB2 alloy powder with a purity of 3N (average particle size of 20μm) was pressed into shape under a pressure of 200MPa, and then vacuum sintered at a temperature of 1000℃ for 2h to obtain ZrB2 alloy billet.

[0064] (3) The CoTa master alloy obtained in step (1) and the ZrB2 alloy billet obtained in step (2) are batched according to the target material composition requirements, and then a second vacuum suspension melting is performed, including: the CoTa master alloy and the ZrB2 alloy billet are stacked alternately in a crucible, and then the melting furnace is evacuated to a vacuum degree of 5.0 × 10⁻⁶. -3 Pa, then argon gas is introduced into the furnace to a pressure of 0.08 MPa, and then suspension melting is carried out at a temperature of 2300℃. The suspension melting is carried out 3 times to obtain CoZrTaB multi-element alloy melt;

[0065] (4) The CoZrTaB multi-element alloy melt obtained in step (3) is cast into a mold. Before casting, the graphite mold is preheated to 800°C, and then sawing, turning, milling, grinding and polishing are performed in sequence to obtain the CoZrTaB sputtering target. The flatness of the CoZrTaB sputtering target after finishing is 0.03 mm.

[0066] Example 3

[0067] This embodiment provides a method for preparing a CoZrTaB sputtering target, the method comprising the following steps:

[0068] (1) According to the ratio of Co and Ta in the target material, a Co block with a purity of 4N and a Ta block with a purity of 4N are subjected to a first vacuum suspension melting process, including: placing the Co block and Ta block alternately in a crucible in layers, and then evacuating the melting furnace to a vacuum degree of 6.0 × 10⁻⁶. -3 Pa, then argon gas is introduced into the furnace to a pressure of 0.10 MPa, and then suspension melting is carried out at a temperature of 2200℃. The suspension melting is carried out 3 times to obtain a CoTa master alloy.

[0069] (2) ZrB2 alloy powder with a purity of 3N (average particle size of 20μm) was pressed into shape under a pressure of 100MPa and then vacuum sintered at a temperature of 1200℃ for 1h to obtain ZrB2 alloy billet.

[0070] (3) The CoTa master alloy obtained in step (1) and the ZrB2 alloy billet obtained in step (2) are batched according to the target material composition requirements, and then a second vacuum suspension melting is performed, including: the CoTa master alloy and the ZrB2 alloy billet are stacked alternately in a crucible, and then the melting furnace is evacuated to a vacuum degree of 6.0 × 10⁻⁶. -3 Pa, then argon gas is introduced into the furnace to a pressure of 0.10 MPa, and then suspension melting is carried out at a temperature of 1900℃. The suspension melting is carried out 5 times to obtain CoZrTaB multi-element alloy melt;

[0071] (4) The CoZrTaB multi-element alloy melt obtained in step (3) is cast into a mold. Before casting, the graphite mold is preheated to 500°C, and then sawing, turning, milling, grinding and polishing are performed in sequence to obtain the CoZrTaB sputtering target. The flatness of the CoZrTaB sputtering target after finishing is 0.02 mm.

[0072] Example 4

[0073] This embodiment provides a method for preparing a CoZrTaB sputtering target. The only difference between this method and that of Example 1 is that the number of suspension melting operations in the first vacuum suspension melting is 1.

[0074] Example 5

[0075] This embodiment provides a method for preparing a CoZrTaB sputtering target. The only difference between this method and that of Example 1 is that the suspension melting temperature in the second vacuum suspension melting is 1800℃.

[0076] Example 6

[0077] This embodiment provides a method for preparing a CoZrTaB sputtering target. The only difference between this method and that of Example 1 is that the suspension melting temperature in the second vacuum suspension melting is 2500℃.

[0078] Example 7

[0079] This embodiment provides a method for preparing a CoZrTaB sputtering target. The only difference between this method and that of Example 1 is that the number of suspension melting operations in the second vacuum suspension melting is 1.

[0080] Comparative Example 1

[0081] This comparative example provides a method for preparing a CoZrTaB sputtering target. The only difference from Example 1 is that step (1) is omitted, and in step (3), the CoTa intermediate alloy is replaced with an equal amount of Co blocks and Ta blocks.

[0082] Comparative Example 2

[0083] This comparative example provides a method for preparing a CoZrTaB sputtering target. The only difference from Example 1 is that step (2) is omitted. In step (3), the ZrB2 alloy billet is replaced with an equal amount of ZrB2 alloy powder, which is the same as step (2) in Example 1.

[0084] The segregation degree of Co, Zr, Ta, and B in the CoZrTaB sputtering targets prepared in Examples 1-7 and Comparative Examples 1-2 was calculated. The calculation method was as follows: three points were randomly selected on the CoZrTaB sputtering target, and the mass percentage content of Co, Zr, Ta, and B elements was measured respectively. The difference between the maximum and minimum mass percentage content at the three points and the average mass percentage content at the three points were calculated. The segregation degree of the elements = difference / average value × 100%. The results are shown in Table 1.

[0085] Table 1

[0086]

[0087]

[0088] The following points can be observed from Table 1:

[0089] (1) As can be seen from the data of Examples 1-3, under preferred conditions, the present invention can reduce the segregation degree of Co to below 0.9%, the segregation degree of Zr to below 0.9%, the segregation degree of Ta to below 0.9%, and the segregation degree of B to below 0.6%.

[0090] (2) By comparing the data of Example 1 and Examples 4-7, it can be seen that the present invention can further reduce segregation by optimizing the number of suspension meltings and the temperature of suspension melting.

[0091] (3) Comparing the data of Example 1 and Comparative Examples 1-2, it can be seen that the present invention can significantly reduce the degree of segregation by using CoTa master alloy and ZrB2 alloy billet.

[0092] In summary, the preparation method provided by this invention solves the problem of uniform distribution of high-melting-point Ta and light element B, and obtains CoZrTaB target material with uniform composition, dense structure and excellent performance.

[0093] The applicant declares that the above description is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention fall within the protection and disclosure scope of the present invention.

Claims

1. A method for preparing a CoZrTaB sputtering target, characterized in that, The preparation method includes the following steps: (1) According to the ratio of Co and Ta in the target material, the Co raw material and the Ta raw material are subjected to the first vacuum suspension melting to obtain the CoTa intermediate alloy. (2) ZrB2 alloy powder is pressed and vacuum sintered in sequence to obtain ZrB2 alloy billet; (3) The CoTa intermediate alloy obtained in step (1) and the ZrB2 alloy billet obtained in step (2) are prepared according to the composition requirements of the target material, and then a second vacuum suspension melting is carried out to obtain CoZrTaB multi-element alloy melt. (4) The CoZrTaB multi-element alloy melt obtained in step (3) is cast into a CoZrTaB sputtering target.

2. The preparation method according to claim 1, characterized in that, The purity of the Co raw material mentioned in step (1) is ≥4N; Preferably, the purity of the Ta raw material is ≥4N.

3. The preparation method according to claim 1 or 2, characterized in that, Step (1) The first vacuum suspension melting includes: placing Co raw material and Ta raw material alternately in a crucible in layers, then evacuating the melting furnace and filling it with argon gas in sequence, and then performing suspension melting; Preferably, the vacuum degree after vacuuming in the first vacuum suspension melting process is 4.0 × 10⁻⁶. -3 -6.0×10 -3 Pa; Preferably, the furnace pressure after argon gas is introduced during the first vacuum suspension melting process is 0.06-0.10 MPa; Preferably, the temperature of the suspension melting in the first vacuum suspension melting is 1800-2200℃; Preferably, the number of suspension melting processes in the first vacuum suspension melting is 3-5 times.

4. The preparation method according to any one of claims 1-3, characterized in that, The purity of the ZrB2 alloy powder in step (2) is ≥3N; Preferably, the average particle size of the ZrB2 alloy powder is 10-30 μm.

5. The preparation method according to any one of claims 1-4, characterized in that, The pressing pressure in step (2) is 100-200 MPa.

6. The preparation method according to any one of claims 1-5, characterized in that, The vacuum sintering temperature in step (2) is 1000-1200℃; Preferably, the vacuum sintering time is 1-2 hours.

7. The preparation method according to any one of claims 1-6, characterized in that, Step (3) The second vacuum suspension melting includes: stacking CoTa master alloy and ZrB2 alloy billet alternately in a crucible, then evacuating and filling the melting furnace with argon gas in sequence, and then performing suspension melting; Preferably, the vacuum degree after vacuuming in the second vacuum suspension melting process is 4.0 × 10⁻⁶. -3 -6.0×10 -3 Pa; Preferably, the furnace pressure after argon gas is introduced during the second vacuum suspension melting process is 0.06-0.10 MPa; Preferably, the temperature of the suspension melting in the second vacuum suspension melting is 1900-2300℃; Preferably, the number of suspension melting processes in the second vacuum suspension melting is 3-5 times.

8. The preparation method according to any one of claims 1-7, characterized in that, In step (4), the mold is preheated before casting. Preferably, the preheating temperature is 500-800℃.

9. The preparation method according to any one of claims 1-8, characterized in that, After casting and molding as described in step (4), further finishing is performed; Preferably, the finishing process includes sawing, turning, milling, grinding, and polishing performed sequentially.

10. The preparation method according to claim 9, characterized in that, The flatness of the CoZrTaB sputtering target after finishing is ≤0.05mm.

Images