Aluminum target material, method of making and use thereof

Abstract

The application provides an aluminum target material and a preparation method and application thereof. The aluminum target material provided by the application is uniformly distributed with equiaxed grains in the inside, the average size of the equiaxed grains is less than or equal to 150 mu m, and the size uniformity of the equiaxed grains is plus or minus 30 mu m. The aluminum target material provided by the application is uniformly distributed with equiaxed grains in the inside, the average size of the equiaxed grains is less than or equal to 150 mu m, and the size uniformity of the equiaxed grains is plus or minus 30 mu m, which can not only improve the uniformity of magnetron sputtering, but also is beneficial to improving the stability of magnetron sputtering, has a wide application prospect in the fields of electronic industry, aerospace and transportation energy, and can meet the application requirements in the fields of flat panel display, integrated circuit and photovoltaic cell.

Description

Technical Field

[0001] This application relates to the field of target technology, and more specifically, to an aluminum target, its preparation method, and its application. Background Technology

[0002] Aluminum and its alloys are the second most widely used industrial raw materials in daily life, after steel. In industrial production, aluminum can be classified into primary aluminum, pure aluminum, refined aluminum, high-purity aluminum, and recycled aluminum. High-purity aluminum is a high-value aluminum metal produced from industrial pure aluminum through a combination of electrolytic refining, segregation, and purification processes. In China, aluminum ingots with a purity exceeding 99.996% are considered high-purity aluminum. Compared to industrial pure aluminum, high-purity aluminum has better electrical and thermal conductivity, corrosion resistance, and lower magnetic permeability. These superior properties are the main reasons for its widespread application in many fields such as electronics, aerospace, transportation, and energy.

[0003] Among the many applications of high-purity aluminum, sputtering targets for integrated circuits account for the largest market consumption, exceeding 50% of the total high-purity aluminum consumption. Magnetron sputtering technology primarily forms a film on integrated circuits by bombarding aluminum targets with high-energy particles. This technology applies high-purity aluminum to fields such as flat panel displays, integrated circuits, and photovoltaic cells, with flat panel displays accounting for more than one-third of the market share. According to the principle of aluminum target magnetron sputtering, the grain size of the sputtering target has a significant impact on the quality of the sputtered film. For sputtering targets of the same composition, the finer and more uniform the grains, the faster the sputtering rate and the more uniform the film thickness distribution. Therefore, aluminum targets need to have a highly uniform fine-grained structure.

[0004] From high-purity aluminum ingots to aluminum sputtering targets, the target processing is an indispensable part. The quality of the target preparation process directly determines the quality of the final target product. Domestically, there are many major aluminum sputtering target manufacturers, but there is still a gap between their products and application requirements. Existing market products suffer from problems such as difficulty in controlling uniform composition, poor microstructure control, and low backing plate bonding rates, failing to meet market application needs. Therefore, technological improvements are urgently needed to enhance the overall quality of the targets. High-purity aluminum, due to its high purity and low impurity content, presents challenges in target processing, including difficulty in controlling grain structure, susceptibility to structural deformation, and abnormal recrystallization grain growth.

[0005] Some researchers have used a double-action reverse extrusion combined with heat treatment to prepare rotating high-purity aluminum targets for planar displays. They employ a 2500T double-action reverse extrusion press as the extrusion equipment, controlling the total deformation to over 80%. During extrusion, the raw aluminum ingot is heated to a semi-molten state, thereby inhibiting the precipitation of soluble phases from the solid solution or causing them to precipitate as fine particles, which facilitates subsequent extrusion molding. Subsequently, annealing is performed to eliminate internal stress, resulting in a rotating target microstructure with fine grains, uniform structure, and no surface fracture matrix detachment. However, this preparation method has the following shortcomings in practical applications: Firstly, the extrusion process requires the aluminum ingot to be in a "semi-molten" state, resulting in an extremely narrow process window and requiring highly precise control of temperature, deformation rate, and pressure. Slight fluctuations can easily lead to defects such as liquid phase segregation, uneven microstructure, or thermal cracking. Secondly, this method relies on large-tonnage double-action reverse extrusion equipment, resulting in high equipment investment and mold maintenance costs. Furthermore, the semi-molten processing is sensitive to the purity and gas content of the raw material, increasing the difficulty of controlling process stability and yield.

[0006] In view of the above, this application is hereby submitted. Summary of the Invention

[0007] The main objective of this application is to provide an aluminum target material, its preparation method, and its application, in order to solve at least one of the following problems in the prior art: difficulty in controlling the grain structure, easy occurrence of structural deformation, and abnormal growth of recrystallized grains during the processing of high-purity aluminum targets; and high investment in equipment and high process requirements for preparing high-purity aluminum targets using the "semi-molten" method.

[0008] To achieve the above objectives, according to one aspect of this application, an aluminum target material is provided, wherein equiaxed grains are uniformly distributed inside the aluminum target material, the average size of the equiaxed grains is ≤150μm, and the size uniformity of the equiaxed grains is ±30μm.

[0009] Furthermore, the aluminum sputtering target contains ≥99.996% aluminum by mass.

[0010] Furthermore, the thickness of the aluminum target material is 10~15mm.

[0011] To achieve the above objectives, according to another aspect of this application, a method for preparing an aluminum target is provided, the method comprising: step S1, pretreating an aluminum ingot to obtain a pretreated aluminum block; step S2, sequentially and alternately subjecting the pretreated aluminum block to liquid nitrogen immersion treatment and rolling deformation to obtain an aluminum target; wherein the temperature of the liquid nitrogen immersion treatment is -196℃ to -100℃, and the time of the liquid nitrogen immersion treatment is 5 to 20 minutes.

[0012] Furthermore, the liquid nitrogen immersion treatment temperature is -196℃ to -125℃.

[0013] Furthermore, the liquid nitrogen immersion treatment time is 5~15 minutes.

[0014] Furthermore, the rolling deformation temperature is 20~30℃.

[0015] Furthermore, the total deformation during rolling is 80% to 90%.

[0016] Furthermore, the thickness of the aluminum target material is 10~15mm.

[0017] Furthermore, the rolling deformation is transformed into unidirectional multi-pass rolling.

[0018] Furthermore, the deformation per pass in unidirectional multi-pass rolling is 15% to 20%.

[0019] Further, in step S1, the pretreatment includes machining, which includes at least one of sawing, wire cutting, or milling and turning.

[0020] Furthermore, the pretreatment includes a cleaning process, the temperature of which is 20~30℃, and the cleaning process is repeated 1~2 times.

[0021] Furthermore, the aluminum content in the aluminum ingot is ≥99.996% by mass.

[0022] According to a third aspect of this application, the application of the aluminum sputtering target provided in the first aspect above, or the aluminum sputtering target obtained according to the preparation method provided in the second aspect above, is provided in the fields of electronics, aerospace, or transportation and energy.

[0023] By applying the technical solution of this application, the aluminum target material provided by this application has equiaxed grains uniformly distributed inside, with an average size of ≤150μm and a uniformity of ±30μm. This not only improves the uniformity of magnetron sputtering but also enhances its stability. It has broad application prospects in the fields of electronics, aerospace, transportation, and energy, and can meet the application requirements of flat panel displays, integrated circuits, and photovoltaic cells. Attached Figure Description

[0024] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The illustrative embodiments and descriptions of this application are used to explain this application and do not constitute an undue limitation of this application. In the drawings:

[0025] Figure 1 A schematic diagram of the preparation process of the aluminum target material provided in Embodiment 1 of this application is shown; and

[0026] Figure 2 A photograph of the cross-section of the aluminum target provided in Embodiment 1 of this application is shown;

[0027] Figure 3 A metallographic microscope image of the cross-section of the aluminum target provided in Embodiment 1 of this application is shown. The observation equipment used is a ZEISS Axioscope 5 upright metallographic microscope. Detailed Implementation

[0028] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The present application will now be described in detail with reference to the embodiments.

[0029] As described in the background section of this application, due to the high purity and low impurity content of high-purity aluminum, the processing of its target material faces challenges such as difficulty in controlling grain structure, easy occurrence of structural deformation and abnormal growth of recrystallized grains, as well as the high investment in equipment and demanding process requirements for preparing high-purity aluminum target materials using a "semi-molten" method. To alleviate these problems, this application provides an aluminum target material, its preparation method, and its application.

[0030] In a first typical embodiment of this application, an aluminum target material is provided, which has equiaxed grains uniformly distributed inside, the average size of the equiaxed grains being less than 150 μm, and the size uniformity of the equiaxed grains being ±30 μm.

[0031] In this application, equiaxed grains refer to grains that are approximately equal in three dimensions (length, width, and height) and are circular or near-circular when viewed from all directions.

[0032] In this application, the size uniformity of equiaxed grains is ±30μm, which means that the size of a single equiaxed grain inside the aluminum target material deviates from the average size of the equiaxed grains inside the aluminum target material within a range of ±30μm.

[0033] The aluminum sputtering target provided in this application has equiaxed grains uniformly distributed inside. The average size of the equiaxed grains is ≤150μm, and the size uniformity of the equiaxed grains is ±30μm. This not only improves the uniformity of magnetron sputtering but also helps to improve the stability of magnetron sputtering. It has broad application prospects in the fields of electronics, aerospace, transportation, and energy, and can meet the application requirements of flat panel displays, integrated circuits, and photovoltaic cells.

[0034] In the internal structure of the high-purity target material provided in this application, the average size of the equiaxed grains is, for example, 100μm, 110μm, 120μm, 130μm, 140μm, 145μm, 150μm or any range of two values; the uniformity of the equiaxed grains is, for example, ±5μm, ±10μm, ±15μm, ±20μm, ±25μm, ±30μm, etc.

[0035] In some embodiments of this application, the aluminum target material contains ≥99.996% aluminum by mass, which is beneficial for the coating formed by sputtering to have better electrical conductivity, thermal conductivity, corrosion resistance and magnetic permeability, and thus is more suitable for application in flat panel displays, integrated circuits and photovoltaic cells.

[0036] In some embodiments of this application, the thickness of the aluminum target is 10-15 mm to meet the target thickness requirements. Specifically, the thickness of the aluminum target is 10 mm, 11 mm, 12 mm, 13 mm, 14 mm, 15 mm, or any combination of two values.

[0037] In a second typical embodiment of this application, a method for preparing an aluminum target is provided, which includes the following steps: Step S1, pre-treating an aluminum ingot to obtain a pre-treated aluminum block; Step S2, alternatingly subjecting the pre-treated aluminum block to cryogenic treatment and rolling deformation to obtain an aluminum target; wherein, the cryogenic treatment is liquid nitrogen immersion treatment, the temperature of the liquid nitrogen immersion treatment is -196~-100℃, and the time of the liquid nitrogen immersion treatment is 5~20min.

[0038] The method for preparing aluminum sputtering targets provided in this application involves pretreating aluminum ingots to remove impurities and oxide layers from the surface, resulting in pretreated aluminum blocks. These pretreated aluminum blocks are then subjected to alternating liquid nitrogen immersion and rolling deformation. The liquid nitrogen immersion temperature is controlled at -196 to -100°C, and the immersion time is 5 to 20 minutes. On the one hand, cryogenic treatment effectively suppresses dynamic recovery during rolling deformation, significantly reducing the tendency for abnormal grain growth. On the other hand, liquid nitrogen immersion avoids dimensional instability caused by heat accumulation during rolling deformation and utilizes low temperatures to suppress impurity diffusion, significantly reducing grain boundary segregation. This ensures microstructure uniformity while improving the microcrystallineity of the aluminum sputtering target and reducing the size of equiaxed grains.

[0039] Furthermore, the aluminum sputtering target preparation method provided in this application is simple, has low production cost, and short preparation cycle. The resulting aluminum sputtering target has finer internal grains and a more uniform structure, making it more suitable for use as a sputtering target in the electronics industry, aerospace, transportation, and energy fields.

[0040] In this application, the temperature for liquid nitrogen immersion treatment is -196℃, -190℃, -180℃, -170℃, -160℃, -150℃, -140℃, -130℃, -125℃ or any two of these values; the time for liquid nitrogen immersion treatment is 5 min, 8 min, 10 min, 12 min, 15 min, 18 min, 20 min or any two of these values.

[0041] In some preferred embodiments of this application, the liquid nitrogen immersion treatment temperature is -195~-125℃, which is more conducive to suppressing the dynamic recovery during the rolling deformation process, resulting in finer and more uniform grains inside the aluminum target material and better structural stability.

[0042] In some preferred embodiments of this application, the liquid nitrogen immersion treatment time is 5 to 15 minutes, which is more conducive to improving the performance of aluminum sputtering targets while saving energy.

[0043] In some preferred embodiments of this application, in step S2 above, the rolling deformation temperature is 20~30℃, which is more conducive to the control of the rolling temperature, simplifies the process, and saves energy. Specifically, the rolling deformation temperature is 20℃, 22℃, 25℃, 28℃, 30℃, or any range of two values.

[0044] In some preferred embodiments of this application, the total rolling deformation is 80% to 90% to further promote finer and more uniform grains in the aluminum target and to prepare an aluminum target of suitable thickness for sputtering coating. Specifically, the total rolling deformation is a range of 80%, 82%, 85%, 88%, 90%, or any two of these values.

[0045] In some preferred embodiments of this application, the thickness of the aluminum target is 10-15 mm to meet the requirements of sputtering operation, thereby improving the uniformity and stability of the coating. Specifically, the thickness of the aluminum target is 10 mm, 11 mm, 12 mm, 13 mm, 14 mm, 15 mm, or any combination of two values.

[0046] In some preferred embodiments of this application, in step S2 above, the rolling deformation is a unidirectional multi-pass rolling, which is not only conducive to refining the grain structure to obtain a uniform and fine equiaxed grain structure and eliminating casting defects; but also helps to optimize the crystallographic texture structure and improve the uniformity of magnetron sputtering of the product; at the same time, it helps to reduce grain boundary segregation, promote the uniform distribution of grain boundaries and impurities, and improve the stability of aluminum sputtering products.

[0047] In some preferred embodiments of this application, the single-pass deformation amount of the aforementioned unidirectional multi-pass rolling is 15% to 20%, which is beneficial for improving rolling efficiency while suppressing dynamic recovery during the single-pass rolling deformation process, thereby further promoting continuous grain refinement and improving the uniformity of the microstructure of the aluminum target material. Specifically, the single-pass deformation amount of the unidirectional multi-pass rolling is a range of 15%, 16%, 17%, 18%, 19%, 20%, or any two of these values.

[0048] In some preferred embodiments, the rolling deformation is performed using a two-roll cold rolling mill to further improve the efficiency of the rolling deformation.

[0049] In some preferred embodiments of this application, the pretreatment in step S1 includes machining, which removes impurities and oxide layers from the aluminum ingot surface to obtain a pretreated aluminum block to be rolled, which facilitates subsequent rolling deformation. Machining methods include, but are not limited to, sawing, wire cutting, or a combination of one or more of milling and turning. Machining is preferably performed by sampling from the raw aluminum ingot, and simple, direct machining steps are preferred to reduce the introduction of machining stress.

[0050] In some preferred embodiments of this application, the pretreatment includes a cleaning process. The cleaning temperature is 20-30°C, and the cleaning is performed 1-2 times until no processing residue remains on the surface. Specifically, the cleaning temperature is 20°C, 22°C, 25°C, 28°C, 30°C, or any combination of two of these values.

[0051] The specific cleaning method described above is not limited; you may choose any one or a combination of water washing or cleaning with cleaning agents.

[0052] In some embodiments of this application, the aluminum content in the aluminum ingot is ≥99.996% by mass to meet the purity requirements of high-purity aluminum, which is more conducive to preparing aluminum targets with better electrical conductivity, thermal conductivity, corrosion resistance and magnetic permeability.

[0053] In a third typical embodiment of this application, the application of the aluminum sputtering target provided in the first aspect or the aluminum sputtering target obtained according to the preparation method provided in the second aspect is also provided in the fields of electronics, aerospace or transportation energy.

[0054] The aluminum sputtering target provided in this application has uniformly distributed equiaxed grains inside, with a grain size of less than 150 μm and a uniformity of ±30 μm. This not only improves the uniformity of magnetron sputtering but also enhances its stability. It has broad application prospects in the fields of electronics, aerospace, transportation, and energy, and can meet the application requirements of flat panel displays, integrated circuits, and photovoltaic cells.

[0055] The beneficial effects of this application will be further illustrated below with reference to embodiments and comparative examples.

[0056] Example 1

[0057] This embodiment provides an aluminum target material, such as Figure 1 As shown, it is prepared according to the following steps:

[0058] (1) The high-purity aluminum ingot with an aluminum mass content of 99.999% is machined. First, it is turned to remove the outer oxide scale and some impurities. Then, it is sawed and wire cut. A sample is taken from the center of the high-purity aluminum ingot to obtain a pre-treated aluminum block with a size of 100mm×60mm×40mm (length×width×height).

[0059] (2.1) The pretreated aluminum block was placed in a liquid nitrogen cryogenic chamber for liquid nitrogen immersion treatment. The liquid nitrogen covered the sample surface, the immersion time was 10 min, and the immersion temperature was -196℃, to obtain the aluminum block to be rolled.

[0060] (2.2) The aluminum block to be rolled is subjected to rolling deformation treatment using a twin-roll cold rolling mill with a roll diameter of 400 mm. The rolling deformation is a unidirectional multi-pass rolling process. After each single-pass rolling deformation, the rolled deformed aluminum block is placed back into a liquid nitrogen cryogenic chamber for further liquid nitrogen immersion treatment, while the roll spacing is adjusted to prepare for the next rolling. After the rolled deformed aluminum block is immersed in liquid nitrogen for 10 minutes, it is rolled a second time, with each rolling deformation amount being 18%. Subsequently, liquid nitrogen immersion treatment and single-pass rolling deformation are alternated, with the total deformation amount controlled at 80%~90%, so that the size of the rolled deformed aluminum block meets the target material thickness requirement of 10-15 mm. After rolling is completed, high-purity aluminum target material (purity of 99.999%) is obtained.

[0061] Example 2

[0062] The difference between this embodiment and Embodiment 1 is that the liquid nitrogen immersion time in steps (2.1) and (2.2) is 5 minutes.

[0063] Example 3

[0064] The difference between this embodiment and Embodiment 1 is that the liquid nitrogen immersion time in steps (2.1) and (2.2) is 15 minutes.

[0065] Example 4

[0066] The difference between this embodiment and Embodiment 1 is that the liquid nitrogen immersion time in steps (2.1) and (2.2) is 20 minutes.

[0067] Example 5

[0068] The difference between this embodiment and Embodiment 1 is that in steps (2.1) and (2.2), the temperature of the liquid nitrogen immersion treatment is -100℃ and the average time of the liquid nitrogen immersion treatment is 5 minutes.

[0069] Example 6

[0070] The difference between this embodiment and Embodiment 1 is that in steps (2.1) and (2.2), the temperature of the liquid nitrogen immersion treatment is -100℃ and the time of the liquid nitrogen immersion treatment is 10min.

[0071] Example 7

[0072] The difference between this embodiment and Embodiment 1 is that in steps (2.1) and (2.2), the temperature of the liquid nitrogen immersion treatment is -100℃ and the time of the liquid nitrogen immersion treatment is 15min.

[0073] Example 8

[0074] The difference between this embodiment and Embodiment 1 is that in steps (2.1) and (2.2), the temperature of the liquid nitrogen immersion treatment is -100℃ and the time of the liquid nitrogen immersion treatment is 20min.

[0075] Example 9

[0076] The difference between this embodiment and Embodiment 1 is that in steps (2.1) and (2.2), the temperature of the liquid nitrogen immersion treatment is -125℃ and the time of the liquid nitrogen immersion treatment is 5 minutes.

[0077] Example 10

[0078] The difference between this embodiment and Embodiment 1 is that in steps (2.1) and (2.2), the temperature of the liquid nitrogen immersion treatment is -125℃ and the time of the liquid nitrogen immersion treatment is 10min.

[0079] Example 11

[0080] The difference between this embodiment and Embodiment 1 is that in steps (2.1) and (2.2), the temperature of the liquid nitrogen immersion treatment is -125℃ and the time of the liquid nitrogen immersion treatment is 15min.

[0081] Example 12

[0082] The difference between this embodiment and Embodiment 1 is that in steps (2.1) and (2.2), the temperature of the liquid nitrogen immersion treatment is -125℃ and the time of the liquid nitrogen immersion treatment is 20min.

[0083] Example 13

[0084] The difference between this embodiment and Embodiment 1 is that the liquid nitrogen immersion treatment time in steps (2.1) and (2.2) is 25 minutes.

[0085] Example 14

[0086] The difference between this embodiment and embodiment 1 is that in step (2.2), the total rolling deformation is controlled to be 75%.

[0087] Comparative Example 1

[0088] The difference between this comparative example and Example 1 is that in step (2.2), the aluminum block to be rolled is directly subjected to unidirectional multi-pass rolling during the rolling deformation process, and liquid nitrogen immersion treatment is no longer performed alternately.

[0089] Comparative Example 2

[0090] The difference between this comparative example and Example 1 is that in step (2.1), the temperature of liquid nitrogen immersion is -100℃ and the time of liquid nitrogen immersion is 10min; in step (2.2), the aluminum block to be rolled is directly subjected to unidirectional multi-pass rolling during the rolling deformation process, and liquid nitrogen immersion treatment is no longer performed alternately.

[0091] Comparative Example 3

[0092] The difference between this comparative example and Example 1 is that the aluminum target material was prepared according to the method described in patent CN101638760A. Specifically, the following steps were included:

[0093] (1) Provide an equal channel corner extrusion die, which is made of alloy steel material with a hexahedral structure of 220mm×220mm×20mm. Extrusion channels are provided on two adjacent surfaces of the equal channel corner extrusion die. A 30° rounded chamfer is provided between the input end and the output end of the extrusion channel. A 120° external angle is formed between the input end and the output end of the extrusion channel.

[0094] The ultra-high purity aluminum sheet (high purity aluminum sheet with a purity greater than 5N) obtained by casting is squeezed from the input end of the extrusion channel 1 into the equal channel extrusion die through the extrusion bar and squeezed out from the output end. After each extrusion, the extrusion surface of the ultra-high purity sheet is flipped. With the longitudinal direction of the sheet as the x direction and the transverse direction as the y direction, each extrusion in the x and y directions is completed once, which is one pass. The above extrusion process is repeated for 4 passes.

[0095] (2) The ultra-high purity aluminum sheet obtained after extrusion is subjected to deep cryogenic treatment in a liquid nitrogen environment. This deep cryogenic treatment refers to cooling the ultra-high purity sheet to -20℃.

[0096] (3) The ultra-high purity aluminum sheet after deep cryogenic treatment is rolled in 4 passes with a total deformation of 70%. After each pass, the ultra-high purity aluminum sheet is placed in a liquid nitrogen environment for deep supercooling treatment (cooling the ultra-high purity sheet to -20℃). After deep supercooling treatment, unidirectional rolling is continued to obtain ultra-high purity aluminum target material.

[0097] Comparative Example 4

[0098] The difference between this comparative example and comparative example 3 is that the deep supercooling treatment in steps (2) and (3) refers to cooling the ultra-high purity plate to -50°C; and the rolling passes in step (3) are 8.

[0099] Comparative Example 5

[0100] The difference between this comparative example and comparative example 3 is that the deep supercooling treatment in steps (2) and (3) refers to cooling the ultra-high purity plate to -80°C; and the rolling passes in step (3) are 15.

[0101] Comparative Example 6

[0102] The difference between this comparative example and Example 1 is that the temperature of the liquid nitrogen immersion treatment in steps (2.1) and (2.2) is -80°C.

[0103] Comparative Example 7

[0104] The difference between this comparative example and Example 1 is that the liquid nitrogen immersion time in steps (2.1) and (2.2) is 3 minutes.

[0105] Comparative Example 8

[0106] The difference between this comparative example and Example 1 is that in step (2.2), the total rolling deformation is controlled to be 50%.

[0107] Experimental Example 1

[0108] The internal structure of the aluminum target material provided in Example 1 was observed. Figure 2 A photograph of the cross-section of the aluminum target provided in Example 1. Figure 3 A metallographic microscope image of a cross-section of the aluminum target provided in Embodiment 1 of this application is shown. Figure 2 It can be seen that the aluminum target material provided in Example 1 has equiaxed grains evenly distributed inside, and the equiaxed grains are small and uniform, without obvious defects, holes and pits.

[0109] from Figure 3 It can be seen that the aluminum target material provided in Example 1 has equiaxed grains evenly distributed inside, and the equiaxed grains are fine and uniform, reaching the ~100μm level, with a size uniformity of ±30μm.

[0110] Experimental Example 2

[0111] The average equiaxed grain size of the aluminum target materials provided in the above embodiments and comparative examples were tested respectively, and the uniformity of the equiaxed grain size was detected. The results are shown in Table 1 below.

[0112] The average size and size uniformity of equiaxed grains were measured using the equivalent section method.

[0113] Table 1

[0114]

[0115] As can be seen from Table 1, the comparison between Examples 1-14 of this application and Comparative Examples 1-8 shows that the aluminum target material provided in Examples 1-13 of this application has uniformly distributed equiaxed grains inside, the size of the equiaxed grains is less than 150 μm, and the uniformity of the equiaxed grain size is ±30 μm. This not only improves the uniformity of magnetron sputtering, but also helps to improve the stability of magnetron sputtering.

[0116] A comparison of Examples 1-12 with Example 13 shows that even with liquid nitrogen immersion treatment at temperatures ranging from -196 to -100°C and exceeding 20 minutes, the equiaxed grains within the aluminum target material do not become further uniformly refined. A comparison of Examples 1-12 with Example 14 and Comparative Example 8 shows that controlling the total deformation during rolling to 80%–90% is more effective in reducing the size of the equiaxed grains within the aluminum target material, resulting in finer and more uniform grains.

[0117] A comparison of Examples 1-12 with Comparative Examples 1-7 shows that by controlling the temperature of liquid nitrogen immersion treatment to -196~-100℃ and the time of liquid nitrogen immersion treatment to 5~20min, and alternating between liquid nitrogen immersion treatment and rolling deformation, it is more conducive to reducing the equiaxed grain size inside the aluminum target material, making it finer and more uniform.

[0118] As can be seen from the above description, the embodiments of this application achieve the following technical effects: the aluminum target material provided by this application has uniformly distributed equiaxed grains inside, the size of the equiaxed grains is less than 150μm, and the uniformity of the equiaxed grain size is ±30μm. This not only improves the uniformity of magnetron sputtering, but also helps to improve the stability of magnetron sputtering. It has broad application prospects in the fields of electronics, aerospace, transportation and energy, and can meet the application requirements of flat panel displays, integrated circuits and photovoltaic cells.

[0119] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. An aluminum target material, characterized in that, The aluminum target material has equiaxed grains uniformly distributed inside, with an average size of ≤150μm and a size uniformity of ±30μm.

2. The aluminum target material according to claim 1, characterized in that, The aluminum target material contains ≥99.996% aluminum by mass.

3. The aluminum target material according to claim 1 or 2, characterized in that, The thickness of the aluminum target is 10~15mm.

4. A method for preparing an aluminum target, characterized in that, The preparation method includes: Step S1: Pre-treat the aluminum ingot to obtain a pre-treated aluminum block; Step S2: The pretreated aluminum block is subjected to liquid nitrogen immersion treatment and rolling deformation in sequence to obtain the aluminum target material; The liquid nitrogen immersion treatment is performed at a temperature of -196 to -100°C for 5 to 20 minutes.

5. The preparation method according to claim 4, characterized in that, The temperature for the liquid nitrogen immersion treatment is -196~-125℃; And / or, the liquid nitrogen immersion treatment time is 5~15 min.

6. The preparation method according to claim 4, characterized in that, The rolling deformation temperature is 20~30℃; And / or, the total deformation of the rolling deformation is 80%~90%; And / or, the thickness of the aluminum target is 10~15mm.

7. The preparation method according to claim 4, characterized in that, The rolling deformation is unidirectional multi-pass rolling; Preferably, the deformation amount per pass in the unidirectional multi-pass rolling is 15% to 20%.

8. The preparation method according to claim 4, characterized in that, In step S1, the preprocessing includes machining, which includes at least one of sawing, wire cutting, or milling and turning. And / or, the pretreatment includes a cleaning process, the temperature of which is 20~30℃, and the cleaning process is repeated 1~2 times.

9. The preparation method according to any one of claims 4 to 8, characterized in that, The aluminum ingot contains ≥99.996% aluminum by mass.

10. The application of the aluminum sputtering material according to any one of claims 1 to 3 or the aluminum sputtering material obtained by the preparation method according to any one of claims 4 to 9 in the fields of electronics industry, aerospace or transportation energy.

Images