A method for manufacturing an aluminum-silicon-titanium alloy target

Abstract

The present application relates to a kind of preparation methods of aluminum-silicon-titanium alloy target material, the preparation method includes the following steps: aluminum-silicon-titanium alloy ingot is sequentially subjected to hot forging and first annealing, obtains aluminum-silicon-titanium alloy blank;The aluminum-silicon-titanium alloy blank is sequentially subjected to pressing treatment and second annealing, obtains aluminum-silicon-titanium alloy to be rolled piece;The aluminum-silicon-titanium alloy to be rolled piece is sequentially subjected to rolling treatment and third annealing, obtains aluminum-silicon-titanium alloy target material;Using the procedure that hot forging, pressing treatment and rolling treatment are combined, the grain of aluminum-silicon-titanium alloy target material is refined, average particle size is preferably as low as 82.5 μm below, and particle size distribution is uniform, PDI is preferably as low as 0.43 below, meet the high quality requirement of sputtering target material for semiconductor manufacturing.

Description

Technical Field

[0001] This invention relates to the field of alloy target preparation technology, and more particularly to a method for preparing an aluminum-silicon-titanium alloy target, especially a method for preparing an aluminum-silicon-titanium alloy target with fine and uniform grain size. Background Technology

[0002] Sputtering targets are crucial raw materials in chip manufacturing, with high-purity aluminum and aluminum alloys being the most commonly used. The main components are generally high-purity aluminum, high-purity aluminum-silicon-copper alloys, and high-purity aluminum-copper alloys. The copper and silicon content is customized according to the specific process used. Some processes have special requirements and use high-purity aluminum alloy targets containing silicon and / or titanium. However, there is currently very little research on the deformation processing of this alloy material, and the demand for billets is basically dependent on imports. Moreover, most of the methods used are powder metallurgy, which involves melting and crystallizing powder raw materials to prepare ultra-high-purity aluminum-silicon-titanium alloy targets. There is very little research on subsequent deformation processing of ingots.

[0003] However, although aluminum-silicon-titanium alloy targets prepared by powder metallurgy have high purity, they suffer from casting defects such as large and uneven grain size, porosity, inclusions, compositional segregation, and cracks, resulting in poor sputtering performance when used as semiconductor sputtering targets. For example, CN104416157A discloses a method for preparing titanium-aluminum-silicon alloy targets using cold isostatic pressing and hot isostatic pressing processes. This method eliminates porosity by simply flattening the pores, which may become linear defects after heat treatment, leading to cracks. Furthermore, the significant difference in melting points between aluminum and titanium increases the difficulty of temperature control during target blank preparation, resulting in microscopic defects such as uneven composition and internal structure. Moreover, this method is complex, time-consuming, and requires sophisticated equipment.

[0004] CN102321833A discloses an aluminum-titanium-silicon alloy target and its preparation method, which is prepared by hot pressing sintering. Due to the uneven heating temperature distribution and difficulty in controlling the pressure during the hot pressing sintering process, the quality of the final product is poor. For example, the uniformity of grain size is very poor, the internal density distribution is also uneven, and there are alloy brittle cracks and compositional segregation.

[0005] Therefore, how to deform and process aluminum-silicon-titanium alloy ingots to prepare a high-purity aluminum-silicon-titanium alloy target material with fine grains, uniform grain size distribution, no component segregation, and no cracks is an urgent problem to be solved. Summary of the Invention

[0006] To address the aforementioned technical problems, this invention provides a method for preparing aluminum-silicon-titanium alloy sputtering targets, which can produce high-purity aluminum-silicon-titanium alloy sputtering targets with fine grains, uniform particle size distribution, and uniform microstructure, providing sputtering targets with excellent sputtering performance for semiconductor manufacturing.

[0007] To achieve this objective, the present invention adopts the following technical solution:

[0008] This invention provides a method for preparing an aluminum-silicon-titanium alloy target, the method comprising the following steps:

[0009] (1) The aluminum-silicon-titanium alloy ingot is subjected to preheating treatment, hot forging and first annealing in sequence to obtain aluminum-silicon-titanium alloy billet; the aluminum-silicon-titanium alloy billet is subjected to pressing treatment and second annealing in sequence to obtain aluminum-silicon-titanium alloy parts to be rolled.

[0010] (2) The aluminum-silicon-titanium alloy workpiece to be rolled in step (1) is subjected to rolling treatment and third annealing in sequence to obtain aluminum-silicon-titanium alloy target material.

[0011] The method for preparing the aluminum-silicon-titanium alloy sputtering target of this invention employs a combination of hot forging, pressing, and rolling processes. These three processes work together to deform the aluminum-silicon-titanium alloy ingot. The hot forging process breaks down the dendritic crystals in the ingot and compacts loose areas, resulting in a more uniform microstructure. The pressing process further refines the grains and improves the microstructure. Finally, the rolling process yields a more uniform recrystallized microstructure, enhancing the isotropy of the aluminum-silicon-titanium alloy sputtering target. Compared to aluminum-silicon-titanium alloy sputtering targets prepared by traditional powder metallurgy, the aluminum-silicon-titanium alloy sputtering target obtained by the method of this invention has a finer grain size and more uniform grain distribution, with no component segregation or cracks, and can be directly used as a sputtering target for semiconductor manufacturing.

[0012] Preferably, the aluminum-silicon-titanium alloy ingot in step (1) contains Si: 0.90-1.10 wt% and Ti: 0.15-0.25 wt%, with the remainder being Al and unavoidable impurities.

[0013] Wherein, Si: 0.90~1.10wt%, for example, it can be 0.90wt%, 0.95wt%, 1.0wt% or 1.1wt%; Ti: 0.15~0.25wt%, for example, it can be 0.15wt%, 0.18wt%, 0.20wt%, 0.22wt% or 0.25wt% or 0.25wt%.

[0014] Preferably, the impurities in the aluminum-silicon-titanium alloy ingot in step (1) include any one or a combination of at least two of Mg, Ni or S, wherein typical but non-limiting combinations include combinations of Mg and Ni, combinations of Mg and S or combinations of Ni and S, etc.

[0015] Preferably, before the hot forging in step (1), the aluminum-silicon-titanium alloy ingot is preheated.

[0016] In a further preferred embodiment of the present invention, before the hot forging in step (1), the aluminum-silicon-titanium alloy ingot is preheated. The increase in temperature of the aluminum-silicon-titanium alloy ingot can increase its plasticity, thereby making it easier to undergo plastic deformation in the subsequent hot forging process. It also helps to reduce the internal and external temperature gradient of the aluminum-silicon-titanium alloy ingot, making its temperature more uniform, reducing stress and cracks, and reducing subsequent hot forging defects. In addition, by utilizing the diffusion effect at high temperature, the chemical composition and microstructure of the aluminum-silicon-titanium alloy ingot are more uniform.

[0017] Preferably, the preheating treatment includes preheating followed by preheating.

[0018] Preferably, the final temperature of the preheating is 100-250°C, for example, it can be 100°C, 120°C, 150°C, 180°C, 200°C, 220°C or 250°C.

[0019] Preferably, the pre-heating time is 15 to 60 minutes, for example, it can be 15 minutes, 20 minutes, 25 minutes, 30 minutes, 35 minutes, 40 minutes, 45 minutes, 50 minutes, 55 minutes or 60 minutes.

[0020] Preferably, the hot forging in step (1) includes sequential drawing and upsetting. Preferably, the initial forging temperature of the hot forging in step (1) is 100-250°C, for example, it can be 100°C, 120°C, 150°C, 180°C, 200°C, 220°C or 250°C, etc.

[0021] Preferably, the final forging temperature of the hot forging in step (1) is 200 to 280°C, for example, it can be 200°C, 210°C, 220°C, 230°C, 240°C, 250°C, 260°C, 270°C or 280°C.

[0022] Preferably, the total forging ratio of hot forging in step (1) is 2.0 to 3.5, for example, it can be 2.0, 2.2, 2.5, 2.8, 3.0, 3.2 or 3.5, etc.

[0023] It is worth noting that the total forging ratio mentioned in this invention refers to the height ratio of the aluminum-silicon-titanium alloy ingot before and after hot forging.

[0024] The present invention further preferably uses a total forging ratio of 2.0 to 3.5 for hot forging, which is beneficial for further breaking down dendritic crystals to refine grains and compacting the loose structure to improve the internal structure of the aluminum-silicon-titanium alloy ingot. If the total forging ratio of hot forging is too low, the pores and inclusions inside the aluminum-silicon-titanium alloy ingot will not be fully compacted, thereby reducing its density and mechanical properties, and also resulting in coarser grains, thus affecting its strength and flexibility. If the total forging ratio of hot forging is too high, the aluminum-silicon-titanium alloy ingot will exhibit strong anisotropy, resulting in the formation of obvious fibrous structures inside; it will also cause uneven deformation of the aluminum-silicon-titanium alloy ingot.

[0025] Preferably, step (1) the first annealing includes sequentially performing a first heating, a first holding, and a first cooling.

[0026] The first annealing process after hot forging described in this invention can further improve the plasticity of the obtained aluminum-silicon-titanium alloy billet, which is beneficial to the deformation processing of the subsequent pressing process; moreover, it can eliminate internal stress and prevent the billet from deforming and cracking.

[0027] Preferably, the endpoint temperature of the first heating is 400℃ to 500℃, for example, it can be 400℃, 420℃, 450℃, 480℃ or 500℃.

[0028] Preferably, the first heat preservation time is 15 to 90 minutes, for example, it can be 15 minutes, 20 minutes, 30 minutes, 50 minutes, 70 minutes or 90 minutes.

[0029] Preferably, the first cooling method includes water cooling.

[0030] Preferably, the endpoint temperature of the first cooling is ≤50°C, for example, it can be 50°C, 45°C, 40°C, 35°C or 30°C, etc.

[0031] Preferably, the pressure of the pressing process in step (1) is 3000t to 5000t, for example, it can be 3000t, 3500t, 4000t, 4500t or 5000t.

[0032] Preferably, the pressing process in step (1) includes placing the aluminum-silicon-titanium alloy billet on a hydraulic press and applying external pressure.

[0033] Preferably, the deformation rate of the aluminum-silicon-titanium alloy billet after the pressing process is 30% to 60%, for example, it can be 30%, 35%, 40%, 45%, 50%, 55% or 60%, etc.

[0034] The present invention further preferably specifies that the deformation rate of the aluminum-silicon-titanium alloy billet after the pressing treatment is 30% to 60%. While ensuring further grain refinement, this reduces the anisotropy of the aluminum-silicon-titanium alloy billet, making its properties more consistent in all directions, reducing residual stress, and suppressing deformation and cracking. If the deformation rate of the aluminum-silicon-titanium alloy billet after the pressing treatment is too low, it will result in coarser grains, stronger anisotropy, and a greater tendency to crack. If the deformation rate of the aluminum-silicon-titanium alloy billet after the pressing treatment is too high, it will lead to grain size deviation, localized excessive deformation, or even fracture.

[0035] Preferably, step (1) the second annealing includes sequentially performing a second heating, a second holding, and a second cooling.

[0036] The purpose of the second annealing process after pressing in step (1) of this invention is to reduce the hardness of the obtained aluminum-silicon-titanium alloy workpiece to be rolled, increase its ductility, and facilitate the deformation of the subsequent rolling process; at the same time, it can further refine the grains, making the properties of the entire material more uniform and consistent.

[0037] Preferably, the endpoint temperature of the second heating is 390°C to 500°C, for example, it can be 390°C, 400°C, 450°C, 480°C or 500°C.

[0038] Preferably, the second heat preservation time is 15 to 90 minutes, for example, it can be 15 minutes, 20 minutes, 30 minutes, 50 minutes, 70 minutes or 90 minutes.

[0039] Preferably, the second cooling method includes water cooling.

[0040] Preferably, the endpoint temperature of the second cooling is ≤50°C, for example, it can be 50°C, 45°C, 40°C, 35°C or 30°C.

[0041] Preferably, the total deformation rate of the aluminum-silicon-titanium alloy workpiece after the rolling process in step (2) is 50% to 80%, for example, it can be 50%, 55%, 60%, 65%, 70%, 75% or 80%, etc.

[0042] The present invention further preferably specifies that the total deformation rate of the aluminum-silicon-titanium alloy workpiece after the rolling treatment is 50% to 80%, which further closes the shrinkage cavities remaining in the workpiece, refines the grains, and obtains a more uniform recrystallized structure. If the total deformation rate of the aluminum-silicon-titanium alloy workpiece after the rolling treatment is too low, the thermal conductivity of the resulting aluminum-silicon-titanium alloy target material will not be improved sufficiently, and the shrinkage cavities will not be closed, resulting in a decrease in density. If the total deformation rate of the aluminum-silicon-titanium alloy workpiece after the rolling treatment is too high, its plasticity will be excessively reduced, affecting its formability, and may even cause the material to change from ductile fracture to brittle fracture.

[0043] Preferably, the rolling speed of the rolling process in step (2) is 0.2 to 0.5 m / s, for example, it can be 0.2 m / s, 0.25 m / s, 0.3 m / s, 0.35 m / s, 0.4 m / s, 0.45 m / s or 0.5 m / s, etc.

[0044] Preferably, the rolling process in step (2) is performed in at least 10 passes, such as 10 passes, 12 passes, 15 passes, 18 passes, 20 passes, 22 passes or 24 passes, preferably 18 to 24 passes.

[0045] Preferably, the deformation rate per pass during the rolling process in step (2) is 5% to 15%, for example, it can be 5%, 8%, 10%, 12% or 15%, preferably 8% to 12%.

[0046] The present invention further preferably uses a single-pass deformation rate of 5-15% during the rolling process, which further improves the grain size uniformity of the obtained aluminum-silicon-titanium alloy target. If the deformation rate of a single pass during the rolling process is too low, it will lead to insufficient deformation and will not be able to effectively improve its internal defects. If the deformation rate of a single pass during the rolling process is too high, it will increase the mill load and also increase the surface roughness of the obtained target, thereby increasing the risk of oxidation and wear.

[0047] Preferably, the rolling temperature is 22 to 28°C, for example, 22°C, 25°C, 27°C or 28°C.

[0048] Preferably, the third annealing in step (2) includes a third heating, a third holding, and a third cooling performed sequentially.

[0049] The third annealing process after rolling described in this invention is used to eliminate the internal stress of the obtained aluminum-silicon-titanium alloy target material and avoid deformation or cracking; at the same time, it helps the grains to rearrange and rise, forming a more uniform and stable crystal structure, thereby improving the mechanical properties of the obtained aluminum-silicon-titanium alloy target material.

[0050] Preferably, the endpoint temperature of the third heating is 390-500°C, for example, it can be 390°C, 420°C, 450°C, 480°C or 500°C.

[0051] Preferably, the third heat preservation time is 10 to 30 minutes, for example, it can be 10 minutes, 15 minutes, 20 minutes, 25 minutes or 30 minutes.

[0052] Preferably, the third cooling method includes water cooling.

[0053] Preferably, the endpoint temperature of the third cooling is ≤50℃, for example, it can be 50℃, 45℃, 40℃, 35℃ or 30℃, etc.

[0054] As a further preferred technical solution of the present invention, the preparation method includes the following steps:

[0055] (1) The aluminum-silicon-titanium alloy ingot is first preheated to 100-250℃ and then preheated to 15-60min; then, under the conditions of initial forging temperature of 100-250℃, final forging temperature of 200-280℃, and total forging ratio of 2.0-3.5, it is hot forged by drawing and upsetting in sequence, and then subjected to a first annealing, which includes first heating to 400℃-500℃, then first holding for 15-90min, and then first cooling to ≤50℃ to obtain an aluminum-silicon-titanium alloy billet; the aluminum-silicon-titanium alloy billet is pressed under a pressure of 3000t-5000t until the deformation rate of the aluminum-silicon-titanium alloy billet is 30%-60%; then subjected to a second annealing, which includes first second heating to 390℃-500℃, then second holding for 15-90min, and then second cooling to ≤50℃ to obtain an aluminum-silicon-titanium alloy part to be rolled;

[0056] (2) The aluminum-silicon-titanium alloy workpiece to be rolled in step (1) is rolled at 22-28°C. The rolling process is divided into at least 10 passes, with a rolling speed of 0.2-0.5 m / s and a deformation rate of 5-15% per pass. Then it undergoes a third annealing, which includes first heating to 390°C-500°C, then holding at that temperature for 10-30 min, and then cooling to ≤50°C to obtain the aluminum-silicon-titanium alloy target material.

[0057] Compared with the prior art, the present invention has at least the following beneficial effects:

[0058] The present invention provides a method for preparing aluminum-silicon-titanium alloy sputtering targets. This method involves sequential hot forging, pressing, and rolling processes, followed by annealing after each process. By further optimizing the total forging ratio of the hot forging, the deformation rate of the pressing process, the single-pass reduction rate of the rolling process, and the total deformation rate, the grain size is further refined, with an average grain size preferably below 82.5 μm. This improves the uniformity of grain size distribution, with a PDI preferably below 0.43, reducing anisotropy and thus minimizing cracking and compositional segregation. Compared to aluminum-silicon-titanium alloy sputtering targets prepared by traditional powder metallurgy methods, the process parameters of the method described in this invention are easier to control, and the resulting product has higher quality, meeting the high requirements for sputtering targets used in semiconductor manufacturing. Detailed Implementation

[0059] To facilitate understanding of the present invention, the following embodiments are provided. Those skilled in the art should understand that these embodiments are merely illustrative and should not be construed as limiting the scope of the invention.

[0060] I. Implementation Examples

[0061] Example 1

[0062] This embodiment provides a method for preparing an aluminum-silicon-titanium alloy target, the method comprising the following steps:

[0063] (1) The aluminum-silicon-titanium alloy ingot is first preheated to 180°C and then preheated for 50 min; then, under the conditions of initial forging temperature of 200°C, final forging temperature of 250°C, and total forging ratio of 3.0, it is hot forged by drawing and upsetting in sequence, and then subjected to a first annealing, which includes first heating to 450°C, then holding for 60 min, and then cooling to 25°C to obtain an aluminum-silicon-titanium alloy billet; the aluminum-silicon-titanium alloy billet is pressed under a pressure of 4000t until the deformation rate of the aluminum-silicon-titanium alloy billet is 50%; then subjected to a second annealing, which includes second heating to 450°C, then holding for 60 min, and then cooling to 25°C to obtain an aluminum-silicon-titanium alloy part to be rolled;

[0064] (2) The aluminum-silicon-titanium alloy workpiece to be rolled in step (1) is rolled at 25°C. The rolling process is divided into 18 passes with a rolling speed of 0.4 m / s and a deformation rate of 10% per pass. Then it undergoes a third annealing, which includes first heating to 450°C, then holding at that temperature for 20 min, and then cooling to 25°C to obtain the aluminum-silicon-titanium alloy target material.

[0065] The composition and corresponding content of the aluminum-silicon-titanium alloy ingot described in this embodiment are shown in Table 1.

[0066] Table 1

[0067] content 0.92 0.16 98.92

[0068] Example 2

[0069] This embodiment provides a method for preparing an aluminum-silicon-titanium alloy target, the method comprising the following steps:

[0070] (1) The aluminum-silicon-titanium alloy ingot is first preheated to 250°C and then preheated for 15 minutes; then, under the conditions of initial forging temperature of 100°C, final forging temperature of 200°C, and total forging ratio of 3.5, it is hot forged by drawing and upsetting in sequence, and then subjected to a first annealing, which includes first heating to 500°C, then holding for 30 minutes, and then cooling to 30°C to obtain an aluminum-silicon-titanium alloy billet; the aluminum-silicon-titanium alloy billet is pressed under a pressure of 5000t until the deformation rate of the aluminum-silicon-titanium alloy billet is 60%; then subjected to a second annealing, which includes second heating to 500°C, then holding for 15 minutes, and then cooling to 30°C to obtain an aluminum-silicon-titanium alloy part to be rolled;

[0071] (2) The aluminum-silicon-titanium alloy workpiece to be rolled in step (1) is rolled at 26°C. The rolling process is divided into 18 passes with a rolling speed of 0.2 m / s and a deformation rate of 8% per pass. Then it undergoes a third annealing, which includes first heating to 500°C, then holding at that temperature for 10 min, and then cooling to 28°C to obtain the aluminum-silicon-titanium alloy target material.

[0072] The composition and corresponding content of the aluminum-silicon-titanium alloy ingot described in this embodiment are shown in Table 2.

[0073] Table 2

[0074] content 0.95 0.18 98.87

[0075] Example 3

[0076] This embodiment provides a method for preparing an aluminum-silicon-titanium alloy target, the method comprising the following steps:

[0077] (1) The aluminum-silicon-titanium alloy ingot is first preheated to 100°C and then preheated for 60 min; then, under the conditions of initial forging temperature of 250°C, final forging temperature of 280°C, and total forging ratio of 2.0, it is hot forged by drawing and upsetting in sequence, and then subjected to a first annealing, which includes first heating to 400°C, then holding for 90 min, and then cooling to 26°C to obtain an aluminum-silicon-titanium alloy billet; the aluminum-silicon-titanium alloy billet is pressed under a pressure of 4000t until the deformation rate of the aluminum-silicon-titanium alloy billet is 30%; then subjected to a second annealing, which includes second heating to 390°C, then holding for 90 min, and then cooling to 26°C to obtain an aluminum-silicon-titanium alloy part to be rolled;

[0078] (2) The aluminum-silicon-titanium alloy workpiece to be rolled in step (1) is rolled at 26°C. The rolling process is divided into 24 passes with a rolling speed of 0.5 m / s and a deformation rate of 12% per pass. Then it undergoes a third annealing, which includes first heating to 390°C, then holding at that temperature for 30 min, and then cooling to 26°C to obtain the aluminum-silicon-titanium alloy target material.

[0079] The composition and corresponding content of the aluminum-silicon-titanium alloy ingot described in this embodiment are shown in Table 3.

[0080] Table 3

[0081] content 0.97 0.18 98.85

[0082] Example 4

[0083] This embodiment provides a method for preparing an aluminum-silicon-titanium alloy target. Except for the total forging ratio of hot forging in step (1) being 1.8, the preparation method is the same as in Embodiment 1.

[0084] Example 5

[0085] This embodiment provides a method for preparing an aluminum-silicon-titanium alloy target. Except for the total forging ratio of hot forging in step (1) being 3.8, the preparation method is the same as in Embodiment 1.

[0086] Example 6

[0087] This embodiment provides a method for preparing an aluminum-silicon-titanium alloy target. Except for the final forging temperature of 180°C in step (1), the preparation method is the same as in embodiment 1.

[0088] Example 7

[0089] This embodiment provides a method for preparing an aluminum-silicon-titanium alloy target. Except for the final forging temperature of 300°C in step (1), the preparation method is the same as in embodiment 1.

[0090] Example 8

[0091] This embodiment provides a method for preparing an aluminum-silicon-titanium alloy target. Except for the fact that the deformation rate of the aluminum-silicon-titanium alloy billet after the pressing treatment is 25%, the preparation method is the same as that in Embodiment 1.

[0092] Example 9

[0093] This embodiment provides a method for preparing an aluminum-silicon-titanium alloy target. Except for the fact that the deformation rate of the aluminum-silicon-titanium alloy billet after the pressing treatment is 65%, the preparation method is the same as that in Embodiment 1.

[0094] Example 10

[0095] This embodiment provides a method for preparing an aluminum-silicon-titanium alloy target. Except for the deformation rate of 5% per pass during the rolling process, the preparation method is the same as in Embodiment 1.

[0096] Example 11

[0097] This embodiment provides a method for preparing an aluminum-silicon-titanium alloy target. Except for the deformation rate of 15% per pass during the rolling process, the preparation method is the same as in Embodiment 1.

[0098] Example 12

[0099] This embodiment provides a method for preparing an aluminum-silicon-titanium alloy target. Except for the fact that the total deformation rate of the aluminum-silicon-titanium alloy workpiece after rolling is 45%, the preparation method is the same as in Embodiment 1.

[0100] Example 13

[0101] This embodiment provides a method for preparing an aluminum-silicon-titanium alloy target. Except for the fact that the total deformation rate of the aluminum-silicon-titanium alloy workpiece after rolling is 85%, the preparation method is the same as in Embodiment 1.

[0102] II. Comparative Example

[0103] Comparative Example 1

[0104] This comparative example provides a method for preparing an aluminum-silicon-titanium alloy target. The preparation method is the same as in Example 1 except that step (1) is omitted, i.e., only rolling and third annealing are performed.

[0105] Comparative Example 2

[0106] This comparative example provides a method for preparing an aluminum-silicon-titanium alloy target. Except for the preparation method disclosed in Example 1 of CN114427081A, the preparation method is the same as that in Example 1.

[0107] III. Tests and Results

[0108] The grain size and particle size distribution (TCI image analysis system) of the aluminum-silicon-titanium alloy targets prepared by the preparation methods described in the above embodiments and comparative examples were tested, and their average particle size and polydispersity index (PDI) were calculated; the results are shown in Table 4.

[0109] Table 4

[0110] Example 1 80.2 0.41 Example 2 82.5 0.43 Example 3 81.6 0.42 Example 4 90.5 0.56 Example 5 80.1 0.50 Example 6 92.8 0.52 Example 7 93.4 0.57 Example 8 95.7 0.59 Example 9 89.2 0.61 Example 10 96.8 0.58 Example 11 85.7 0.63 Example 12 92.6 0.59 Example 13 81.7 0.60 Comparative Example 1 105.7 0.75 Comparative Example 2 96.5 0.53

[0111] As can be seen from Table 4:

[0112] (1) As can be seen from Examples 1 to 3, the method for preparing aluminum-silicon-titanium alloy targets provided by the present invention has successfully prepared high-quality aluminum-silicon-titanium alloy targets with an average particle size of less than 82.5 μm, uniform particle size distribution, and PDI value of less than 0.43. It has excellent sputtering performance and can be used as a sputtering target for semiconductor manufacturing.

[0113] (2) As can be seen from the combined examples 1 and 4-7, the total forging ratio of hot forging in example 4 is too low, resulting in an increase in the average particle size of the obtained product to 90.5 μm and an increase in PDI to 0.56. The total forging ratio of hot forging in example 5 is too high, which may cause cracks in the obtained product and uneven particle size distribution. The final forging temperature of hot forging in example 6 is too low, resulting in an increase in the average particle size of the obtained product to 92.8 μm and an increase in PDI to 0.52. The final forging temperature of hot forging in example 7 is too high, resulting in an increase in the average particle size of the obtained product to 93.4 μm and an increase in PDI to 0.57. Therefore, it is indicated that the present invention further preferably has a total forging ratio of 2.0 to 3.5 for hot forging and a final forging temperature of 200 to 280°C, which further refines the grain size and makes the particle size distribution more uniform.

[0114] (3) It can be seen from the combined examples 1 and 8-9 that the deformation rate of the aluminum-silicon-titanium alloy billet after pressing in example 8 is relatively low, resulting in an increase in the average grain size of the product to 95.7 μm and an increase in PDI to 0.59; the deformation rate of the aluminum-silicon-titanium alloy billet after pressing in example 9 is relatively high, resulting in local deformation, uneven grain size distribution, and an increase in PDI to 0.61. This indicates that the present invention further preferably has a deformation rate of 30% to 60% for the aluminum-silicon-titanium alloy billet after pressing, which further refines the grains while ensuring a more uniform grain size distribution.

[0115] (4) Combining Examples 1 and Examples 10-13, it can be seen that in Example 10, the deformation rate per pass during the rolling process was relatively low, resulting in an increase in the average grain size of the obtained product to 96.8 μm and the PDI to 0.58; in Example 11, the deformation rate per pass during the rolling process was relatively high, resulting in uneven grain distribution of the obtained product and an increase in PDI to 0.63; in Example 12, the total deformation rate of the aluminum-silicon-titanium alloy workpiece after the rolling process was relatively low, resulting in an increase in the average grain size to 92.6 μm. μm, PDI increases to 0.59; in Example 13, the total deformation rate of the aluminum-silicon-titanium alloy workpiece after rolling treatment is too high, resulting in uneven grain size and an increase in PDI value to 0.60; thus, it is indicated that the present invention further preferably has a single-pass deformation rate of 8-12% during the rolling process, and further preferably has a total deformation rate of 50%-80% for the aluminum-silicon-titanium alloy workpiece after rolling treatment, which further refines the grain size, makes the grain size distribution more uniform, and further improves the mechanical properties of the product.

[0116] (5) It can be seen from the comprehensive comparison of Example 1 with Comparative Examples 1 and 2 that, since Comparative Example 1 only performed rolling and did not perform hot forging and pressing, the aluminum-silicon-titanium alloy ingot had an uneven crystal structure. Direct rolling could not completely eliminate intragranular segregation and shrinkage porosity, and could not completely achieve internal homogenization. As a result, the average particle size of the product increased to 105.7 μm and the PDI increased to 0.75. Since Comparative Example 2 used the method disclosed in Example 1 of CN114427081A, that is, the powder raw material was melted, degassed and crystallized. The product obtained was comparable to the original aluminum-silicon-titanium alloy ingot used in Example 1 of this invention, and did not further refine the grains or homogenize the structure. This shows that the present invention uses a combination of hot forging, pressing and rolling processes to obtain high-quality aluminum-silicon-titanium alloy targets, which can be used as sputtering targets for semiconductor manufacturing.

[0117] 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 an aluminum-silicon-titanium alloy target, characterized in that, The preparation method includes the following steps: (1) The aluminum-silicon-titanium alloy ingot is first preheated to 100~250℃ and then preheated; then, under the conditions of a final forging temperature of 200~280℃ and a total forging ratio of 2.0~3.5, it is hot forged by drawing and upsetting in sequence, and then annealed for the first time to obtain the aluminum-silicon-titanium alloy billet; the aluminum-silicon-titanium alloy billet is pressed under a pressure of 3500t~5000t until the deformation rate of the aluminum-silicon-titanium alloy billet is 30%~60%; then, it is annealed for the second time to obtain the aluminum-silicon-titanium alloy rolled part; (2) The aluminum-silicon-titanium alloy workpiece to be rolled in step (1) is subjected to rolling treatment and third annealing in sequence to obtain aluminum-silicon-titanium alloy target material; The first annealing includes heating to 400°C~500°C, holding at that temperature for 15~90 minutes, and then cooling to ≤50°C. The second annealing includes heating to 390°C~500°C, holding at that temperature for 15~90 minutes, and then cooling to ≤50°C. The rolling process is performed in at least 10 passes, with a deformation rate of 8-12% per pass. The third annealing includes heating to 390℃~500℃, holding at that temperature for 10~30 minutes, and then cooling to ≤50℃. The aluminum-silicon-titanium alloy ingot contains Si: 0.90~1.10wt% and Ti: 0.15~0.25wt%, with the remainder being Al and unavoidable impurities; The total deformation rate of the aluminum-silicon-titanium alloy workpiece after the rolling process is 50%~80%.

2. The preparation method according to claim 1, characterized in that, The pre-insulation time is 15~60 minutes.

3. The preparation method according to claim 1, characterized in that, The initial forging temperature for hot forging in step (1) is 100~250℃.

4. The preparation method according to claim 1, characterized in that, The rolling speed of the rolling process in step (2) is 0.2~0.5m / s.

5. The preparation method according to claim 1, characterized in that, The rolling process in step (2) consists of 18 to 24 passes.

6. The preparation method according to claim 1, characterized in that, The rolling temperature is 22~28℃.

7. The preparation method according to claim 1, characterized in that, The preparation method includes the following steps: (1) The aluminum-silicon-titanium alloy ingot is first preheated to 100~250℃ and then preheated to 15~60min; then, under the conditions of initial forging temperature of 100~250℃, final forging temperature of 200~280℃, and total forging ratio of 2.0~3.5, it is hot forged by drawing and upsetting in sequence, and then subjected to the first annealing, which includes first heating to 400℃~500℃, then first holding for 15~90min, and then first cooling to ≤50℃ to obtain aluminum-silicon-titanium alloy billet; the aluminum-silicon-titanium alloy billet is pressed under a pressure of 3500t~5000t until the deformation rate of the aluminum-silicon-titanium alloy billet is 30%~60%; then subjected to the second annealing, which includes first second heating to 390℃~500℃, then second holding for 15~90min, and then second cooling to ≤50℃ to obtain aluminum-silicon-titanium alloy parts to be rolled; (2) The aluminum-silicon-titanium alloy workpiece to be rolled in step (1) is rolled at 22~28℃. The rolling process is divided into at least 10 passes, the rolling speed is 0.2~0.5m / s, and the deformation rate of a single pass is 5~15%. Then it is annealed for the third time. The third annealing includes first heating to 390℃~500℃, then holding for 10~30min, and then cooling to ≤50℃ to obtain the aluminum-silicon-titanium alloy target material.