Method for recycling aluminum-scandium alloy target material

Abstract

The application provides a recycling method of an aluminum-scandium alloy target material, and the recycling method comprises pretreatment, surface impurity removal and vacuum suspension smelting which are sequentially performed; the pretreatment comprises target material classification, removal of a back plate and cutting treatment which are sequentially performed; the surface impurity removal comprises ultrasonic cleaning and drying treatment which are sequentially performed; and the vacuum suspension smelting comprises at least two smelting processes. The recycling method provided by the application significantly improves the recovery rate of metal elements in the target material, avoids the introduction of impurities, shortens the processing period, reduces the recovery cost, and is conducive to large-scale popularization and application.

Description

Technical Field

[0001] This invention belongs to the field of target technology and relates to a method for recycling target materials, particularly a method for recycling aluminum-scandium alloy target materials. Background Technology

[0002] Currently, with the rapid development of electronic information technology, the application of aluminum scandium (AlSc) alloy targets in integrated circuits has increasingly attracted widespread attention from researchers. They are mainly used for magnetron sputtering to prepare high-performance piezoelectric thin film materials for 5G filters. The sputtering process of the target is mainly through physical vapor deposition (PVD), which uses high-pressure accelerated gaseous ions to bombard the target, causing the target atoms to be sputtered out and deposited as thin films on silicon wafers or other substrates. Combined with photolithography and other processes, this ultimately forms the complex wiring structure in semiconductor chips.

[0003] Sc, an element found in AlSc alloy sputtering targets, is extremely scarce and expensive. Sc is a rare earth element, comprising only 0.0005% of the Earth's crust, making its reserves extremely low and its extraction from mineral deposits very difficult. As a rare and valuable strategic material, the effective recycling and utilization of Sc is of great significance.

[0004] However, there are few reports on the recycling of AlSc alloys in various technical fields, with most reports focusing on the recovery of the rare earth element Sc. Due to the special nature of the target material industry, the direct recycling of AlSc alloy residues from waste targets is highly feasible.

[0005] Therefore, how to provide a method for recycling aluminum-scandium alloy targets, improve the recovery rate of metal elements in the targets, avoid the introduction of impurities, shorten the processing cycle, and reduce recycling costs has become an urgent problem that needs to be solved by those skilled in the art. Summary of the Invention

[0006] In view of the shortcomings of the existing technology, the purpose of this invention is to provide a method for recycling aluminum-scandium alloy targets. The recycling method significantly improves the recovery rate of metal elements in the target, avoids the introduction of impurities, shortens the processing cycle, reduces recycling costs, and is conducive to large-scale promotion and application.

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

[0008] This invention provides a method for recycling aluminum-scandium alloy targets, the recycling method comprising pretreatment, surface impurity removal and vacuum suspension melting performed sequentially.

[0009] The pretreatment includes target sorting, backplate removal, and cutting processes performed sequentially.

[0010] The surface cleaning process includes sequential ultrasonic cleaning and drying.

[0011] The vacuum suspension melting process includes at least two melting processes, such as two, three, four, five or six, but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0012] The recycling method provided by this invention achieves efficient recycling of aluminum-scandium alloy targets by sequentially performing pretreatment, surface impurity removal, and vacuum suspension melting. The pretreatment cuts the complete aluminum-scandium alloy target into aluminum-scandium alloy blocks of suitable size for cleaning and melting. Surface impurity removal avoids the introduction of impurities and improves the purity of the aluminum-scandium alloy ingots obtained from melting. Vacuum suspension melting, with at least two melting processes, fully recovers the target metal elements in the aluminum-scandium alloy target, significantly improving the recovery rate of metal elements in the target. The entire recycling process has a short processing cycle and low recycling cost, which is conducive to large-scale promotion and application.

[0013] Preferably, the target material classification is based on the composition ratio of the aluminum-scandium alloy target material.

[0014] Preferably, the classification criteria include selecting aluminum-scandium alloy targets with a scandium content of 5-50 wt%, such as 5 wt%, 10 wt%, 15 wt%, 20 wt%, 25 wt%, 30 wt%, 35 wt%, 40 wt%, 45 wt%, or 50 wt%, but are not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0015] Preferably, the removal of the backplate is performed by machining.

[0016] Preferably, the machining position during the machining process is 1-5mm lower than the aluminum-scandium alloy target welding line, for example, it can be 1mm, 1.5mm, 2mm, 2.5mm, 3mm, 3.5mm, 4mm, 4.5mm or 5mm, but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0017] In this invention, since the aluminum alloy backplate and the aluminum-scandium alloy target are not easily distinguishable in appearance, the machining position is limited to 1-5mm below the welding line of the aluminum-scandium alloy target during the machining process. Then, the backplate on the target can be quickly identified by a conductivity meter or a handheld XRF device.

[0018] Preferably, the cutting process includes: cutting the aluminum-scandium alloy target material after removing the backplate into aluminum-scandium alloy blocks.

[0019] Preferably, the longest side of the aluminum-scandium alloy block is ≤5cm, for example, it can be 1mm, 1.5mm, 2mm, 2.5mm, 3mm, 3.5mm, 4mm, 4.5mm or 5mm, but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0020] The present invention limits the longest side of the cut aluminum-scandium alloy block to less than 5cm, which makes it easier to put it into the melting crucible for subsequent vacuum suspension melting.

[0021] Preferably, the cleaning solution used in the ultrasonic cleaning includes an alkaline solution or an acidic solution.

[0022] Preferably, the alkaline solution comprises sodium hydroxide solution and / or potassium hydroxide solution.

[0023] Preferably, the concentration of the alkaline solution is 10-20 wt%, for example, it can be 10 wt%, 11 wt%, 12 wt%, 13 wt%, 14 wt%, 15 wt%, 16 wt%, 17 wt%, 18 wt%, 19 wt%, or 20 wt%, but it is not limited to the listed values, and other unlisted values ​​within this range are also applicable.

[0024] Preferably, the acid solution includes any one or a combination of at least two of nitric acid solution, hydrochloric acid solution, sulfuric acid solution or hydrofluoric acid solution. Typical but non-limiting combinations include combinations of nitric acid solution and hydrochloric acid solution, combinations of hydrochloric acid solution and sulfuric acid solution, combinations of sulfuric acid solution and hydrofluoric acid solution, combinations of nitric acid solution, hydrochloric acid solution and sulfuric acid solution, or combinations of hydrochloric acid solution, sulfuric acid solution and hydrofluoric acid solution.

[0025] Preferably, the concentration of the acid solution is 4-8 wt%, for example, it can be 4 wt%, 4.5 wt%, 5 wt%, 5.5 wt%, 6 wt%, 6.5 wt%, 7 wt%, 7.5 wt%, or 8 wt%, but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0026] Preferably, the ultrasonic cleaning frequency is 20-40kHz, for example, it can be 20kHz, 22kHz, 24kHz, 26kHz, 28kHz, 30kHz, 32kHz, 34kHz, 36kHz, 38kHz or 40kHz, but it is not limited to the listed values, and other unlisted values ​​within this range are also applicable.

[0027] Preferably, the ultrasonic cleaning time is 30-60 minutes, for example, 30 minutes, 35 minutes, 40 minutes, 45 minutes, 50 minutes, 55 minutes or 60 minutes, but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0028] Preferably, the ultrasonic cleaning process is accompanied by a rotary shearing process to fully remove impurities adhering to the surface of the aluminum-scandium alloy.

[0029] Preferably, the ultrasonic cleaning and drying process further includes a deionized water rinse.

[0030] Preferably, the drying process includes hot air circulation drying.

[0031] Preferably, the temperature of the hot air circulation drying is 40-80℃, for example, it can be 40℃, 45℃, 50℃, 55℃, 60℃, 65℃, 70℃, 75℃ or 80℃, but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0032] Preferably, the hot air circulation drying time is 30-60 minutes, for example, it can be 30 minutes, 35 minutes, 40 minutes, 45 minutes, 50 minutes, 55 minutes or 60 minutes, but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0033] Preferably, the vacuum suspension melting process is accompanied by the addition of aluminum and / or scandium to adjust the element ratio.

[0034] Preferably, the temperature of the vacuum suspension melting is 1550-1650℃, for example, it can be 1550℃, 1560℃, 1570℃, 1580℃, 1590℃, 1600℃, 1610℃, 1620℃, 1630℃, 1640℃ or 1650℃, but it is not limited to the listed values, and other unlisted values ​​within this range are also applicable.

[0035] In this invention, the temperature of the vacuum suspension melting process needs to be controlled within a reasonable range. When the temperature is below 1550℃, the metallic scandium is not completely melted, making it difficult to remove impurities and thus affecting the purity of the resulting aluminum-scandium alloy ingot. When the temperature is above 1650℃, the improvement in the purity of the resulting aluminum-scandium alloy ingot is not significant, and it leads to an unnecessary increase in processing costs.

[0036] Preferably, the vacuum suspension melting time is 40-80 min, for example, it can be 40 min, 45 min, 50 min, 55 min, 60 min, 65 min, 70 min, 75 min or 80 min, but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0037] Preferably, the absolute vacuum degree of the vacuum suspension melting is 0.01-0.05 Pa, for example, it can be 0.01 Pa, 0.015 Pa, 0.02 Pa, 0.025 Pa, 0.03 Pa, 0.035 Pa, 0.04 Pa, 0.045 Pa or 0.05 Pa, but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0038] Preferably, the recycling method yields aluminum-scandium alloy ingots with a purity ≥ 99.99 wt%, such as 99.99 wt%, 99.992 wt%, 99.994 wt%, 99.996 wt%, 99.998 wt%, or 99.999 wt%, but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0039] In this invention, the purity detection method for the aluminum-scandium alloy ingot can refer to GB / T 20975-2008 Chemical Analysis Methods for Aluminum and Aluminum Alloys.

[0040] Preferably, the aluminum-scandium alloy ingot is used to prepare aluminum-scandium alloy targets and / or aluminum-scandium alloy backplates.

[0041] As a preferred embodiment of the present invention, the recycling method includes the following steps:

[0042] (1) Pretreatment: Select an aluminum-scandium alloy target with a scandium content of 5-50wt%, and machine the aluminum-scandium alloy target to remove the back plate. The machining position is 1-5mm lower than the welding line of the aluminum-scandium alloy target. Cut the aluminum-scandium alloy target after removing the back plate into aluminum-scandium alloy blocks, and the longest side of the aluminum-scandium alloy blocks is ≤5cm.

[0043] (2) Surface impurity removal: The obtained aluminum-scandium alloy block is subjected to ultrasonic cleaning, deionized water rinsing, and hot air circulation drying in sequence; the cleaning solution used for ultrasonic cleaning includes alkaline solution or acid solution; the alkaline solution includes sodium hydroxide solution and / or potassium hydroxide solution, and the concentration is 10-20wt%; the acid solution includes any one or a combination of at least two of nitric acid solution, hydrochloric acid solution, sulfuric acid solution or hydrofluoric acid solution, and the concentration is 4-8wt%; the ultrasonic cleaning frequency is 20-40kHz, the time is 30-60min, and the cleaning process is accompanied by rotational shearing treatment; the hot air circulation drying temperature is 40-80℃, and the time is 30-60min;

[0044] (3) Vacuum suspension melting: The aluminum-scandium alloy block after surface impurity removal is placed in a melting crucible and vacuum suspended at 1550-1650℃ for 40-80 min, including at least 2 melting processes, and the absolute vacuum degree of melting is 0.01-0.05 Pa. During the melting process, aluminum and / or scandium are added to adjust the element ratio, and finally aluminum-scandium alloy ingots with a purity ≥99.99wt% are obtained. The obtained aluminum-scandium alloy ingots are subsequently used to prepare aluminum-scandium alloy targets and / or aluminum-scandium alloy backplates.

[0045] The numerical range described in this invention includes not only the point values ​​listed above, but also any point values ​​within the numerical ranges not listed above. Due to space limitations and for the sake of brevity, this invention will not exhaustively list all the specific point values ​​included in the range.

[0046] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0047] The recycling method provided by this invention achieves efficient recycling of aluminum-scandium alloy targets by sequentially performing pretreatment, surface impurity removal, and vacuum suspension melting. The pretreatment cuts the complete aluminum-scandium alloy target into aluminum-scandium alloy blocks of suitable size for cleaning and melting. Surface impurity removal avoids the introduction of impurities and improves the purity of the aluminum-scandium alloy ingots obtained from melting. Vacuum suspension melting, with at least two melting processes, fully recovers the target metal elements in the aluminum-scandium alloy target, significantly improving the recovery rate of metal elements in the target. The entire recycling process has a short processing cycle and low recycling cost, which is conducive to large-scale promotion and application. Detailed Implementation

[0048] The technical solution of the present invention will be further illustrated below through specific embodiments.

[0049] Example 1

[0050] This embodiment provides a method for recycling aluminum scandium alloy targets, the recycling method comprising the following steps:

[0051] (1) Pretreatment: Select an aluminum-scandium alloy target with a scandium content of 35-50wt%, and machine the aluminum-scandium alloy target to remove the back plate. The machining position is 3mm lower than the welding line of the aluminum-scandium alloy target. Cut the aluminum-scandium alloy target after removing the back plate into aluminum-scandium alloy blocks, and the longest side of the aluminum-scandium alloy blocks is ≤4cm.

[0052] (2) Surface impurity removal: The obtained aluminum-scandium alloy block was subjected to ultrasonic cleaning, deionized water rinsing, and hot air circulation drying in sequence; the ultrasonic cleaning solution used was sodium hydroxide solution with a concentration of 15wt%; the ultrasonic cleaning frequency was 30kHz and the time was 45min, and the cleaning process was also accompanied by rotational shearing to fully remove impurities attached to the surface of the aluminum-scandium alloy; the hot air circulation drying temperature was 60℃ and the time was 45min.

[0053] (3) Vacuum suspension melting: The aluminum-scandium alloy block after surface impurity removal was placed in a melting crucible and vacuum suspended at 1600℃ for 60 min, including two melting processes, and the absolute vacuum degree of melting was 0.04 Pa. Aluminum was added during the melting process to adjust the element ratio, and finally an aluminum-scandium alloy ingot with a purity of 99.994 wt% was obtained. The purity detection method refers to GB / T 20975-2008 Chemical Analysis Methods for Aluminum and Aluminum Alloys. The obtained aluminum-scandium alloy ingot was subsequently used to prepare aluminum-scandium alloy targets and aluminum-scandium alloy backplates.

[0054] Example 2

[0055] This embodiment provides a method for recycling aluminum scandium alloy targets, the recycling method comprising the following steps:

[0056] (1) Pretreatment: Select an aluminum-scandium alloy target with a scandium content of 5-35wt%, and machine the aluminum-scandium alloy target to remove the back plate. The machining position is 1mm lower than the welding line of the aluminum-scandium alloy target. Cut the aluminum-scandium alloy target after removing the back plate into aluminum-scandium alloy blocks, and the longest side of the aluminum-scandium alloy blocks is ≤3cm.

[0057] (2) Surface impurity removal: The obtained aluminum-scandium alloy block was subjected to ultrasonic cleaning, deionized water rinsing, and hot air circulation drying in sequence; the ultrasonic cleaning solution used was nitric acid solution with a concentration of 6wt%; the ultrasonic cleaning frequency was 20kHz and the time was 60min, and the cleaning process was also accompanied by rotational shearing to fully remove impurities attached to the surface of the aluminum-scandium alloy; the hot air circulation drying temperature was 40℃ and the time was 60min.

[0058] (3) Vacuum suspension melting: The aluminum-scandium alloy block after surface impurity removal is placed in a melting crucible and vacuum suspended at 1550℃ for 80 min, including 3 melting processes, and the absolute vacuum degree of melting is 0.01 Pa. Scandium is added during the melting process to adjust the element ratio, and finally an aluminum-scandium alloy ingot with a purity of 99.99 wt% is obtained. The purity detection method refers to "GB / T 20975-2008 Chemical Analysis Methods for Aluminum and Aluminum Alloys". The obtained aluminum-scandium alloy ingot is subsequently used to prepare aluminum-scandium alloy targets and aluminum-scandium alloy backplates.

[0059] Example 3

[0060] This embodiment provides a method for recycling aluminum scandium alloy targets, the recycling method comprising the following steps:

[0061] (1) Pretreatment: Select an aluminum-scandium alloy target with a scandium content of 20-40wt%, and machine the aluminum-scandium alloy target to remove the back plate. The machining position is 5mm lower than the welding line of the aluminum-scandium alloy target. Cut the aluminum-scandium alloy target after removing the back plate into aluminum-scandium alloy blocks, and the longest side of the aluminum-scandium alloy blocks is ≤5cm.

[0062] (2) Surface impurity removal: The obtained aluminum-scandium alloy block is subjected to ultrasonic cleaning, deionized water rinsing, and hot air circulation drying in sequence; the ultrasonic cleaning solution used is potassium hydroxide solution with a concentration of 10wt%; the ultrasonic cleaning frequency is 40kHz and the time is 30min, and the cleaning process is also accompanied by rotational shearing to fully remove impurities attached to the surface of the aluminum-scandium alloy; the hot air circulation drying temperature is 80℃ and the time is 30min.

[0063] (3) Vacuum suspension melting: The aluminum-scandium alloy block after surface impurity removal was placed in a melting crucible and vacuum suspended at 1650℃ for 40 min, including two melting processes, and the absolute vacuum degree of melting was 0.05 Pa. Aluminum was added during the melting process to adjust the element ratio, and finally an aluminum-scandium alloy ingot with a purity of 99.996 wt% was obtained. The purity detection method refers to GB / T 20975-2008 Chemical Analysis Methods for Aluminum and Aluminum Alloys. The obtained aluminum-scandium alloy ingot was subsequently used to prepare aluminum-scandium alloy targets and aluminum-scandium alloy backplates.

[0064] Example 4

[0065] This embodiment provides a method for recycling aluminum-scandium alloy targets. Except for reducing the temperature of vacuum suspension melting in step (3) to 1545°C, the other steps and conditions are the same as in embodiment 1, so they will not be described in detail here.

[0066] Purity testing was conducted according to GB / T 20975-2008 Chemical Analysis Methods for Aluminum and Aluminum Alloys. The purity of the aluminum-scandium alloy ingot obtained in this embodiment was 99.99%, which was significantly lower than 99.994% in Example 1. This indicates that the low temperature of vacuum suspension melting leads to incomplete melting of metallic scandium, making it difficult to remove impurities and thus affecting the purity of the obtained aluminum-scandium alloy ingot.

[0067] Example 5

[0068] This embodiment provides a method for recycling aluminum-scandium alloy targets. Except for raising the temperature of vacuum suspension melting in step (3) to 1700°C, the other steps and conditions are the same as in embodiment 1, so they will not be described in detail here.

[0069] Purity was tested according to GB / T 20975-2008 Chemical Analysis Methods for Aluminum and Aluminum Alloys. The purity of the aluminum-scandium alloy ingot obtained in this example was 99.995%, which was almost the same as 99.994% in Example 1. That is, the improvement in the purity of the aluminum-scandium alloy ingot was not significant, and instead caused an unnecessary increase in processing costs.

[0070] Comparative Example 1

[0071] This comparative example provides a method for recycling aluminum-scandium alloy targets. Except for changing the number of vacuum suspension melting in step (3) to one melting process, the other steps and conditions are the same as in Example 1, so they will not be described in detail here.

[0072] Purity was tested according to GB / T 20975-2008 Chemical Analysis Methods for Aluminum and Aluminum Alloys. The purity of the aluminum-scandium alloy ingot obtained in this comparative example was 99.95%, which was significantly lower than 99.994% of Example 1. This indicates that the number of vacuum suspension melting processes is crucial for improving the purity of the aluminum-scandium alloy ingot.

[0073] Comparative Example 2

[0074] This comparative example provides a method for recycling aluminum-scandium alloy targets. Except for replacing the vacuum suspension melting in step (3) with conventional melting in air, the other steps and conditions are the same as in Example 1, so they will not be described in detail here.

[0075] Purity was tested according to GB / T 20975-2008 Chemical Analysis Methods for Aluminum and Aluminum Alloys. The purity of the aluminum-scandium alloy ingot obtained in this comparative example was 99.5%, which was significantly lower than 99.994% of Example 1. This indicates that the vacuum environment of melting is crucial for improving the purity of aluminum-scandium alloy ingots.

[0076] Therefore, the recycling method provided by this invention achieves efficient recycling of aluminum-scandium alloy targets by sequentially performing pretreatment, surface impurity removal, and vacuum suspension melting. The pretreatment cuts the complete aluminum-scandium alloy target into aluminum-scandium alloy blocks of suitable size for cleaning and melting. Surface impurity removal avoids the introduction of impurities and improves the purity of the aluminum-scandium alloy ingots obtained from melting. Vacuum suspension melting, with at least two melting processes, fully recovers the target metal elements in the aluminum-scandium alloy target, significantly improving the recovery rate of metal elements in the target. The entire recycling process has a short processing cycle and low recycling cost, which is conducive to large-scale promotion and application.

[0077] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A recycling method of an aluminum scandium alloy target material, characterized by, The recycling method includes pretreatment, surface impurity removal, and vacuum suspension melting performed sequentially. The pretreatment includes sequential target sorting, backplate removal, and cutting. The target material classification is based on the composition ratio of aluminum-scandium alloy targets. The classification criteria include selecting aluminum-scandium alloy targets with a scandium content of 5-50 wt%. The cutting process includes: cutting the aluminum-scandium alloy target material after removing the back plate into aluminum-scandium alloy blocks; The longest side of the aluminum-scandium alloy block is ≤5cm; The surface cleaning process includes sequential ultrasonic cleaning and drying. The ultrasonic cleaning process is also accompanied by a rotary shearing process. The vacuum suspension melting process includes at least two melting processes. The backplate removal is performed by machining. During the machining process, the machining position is 1-5mm lower than the welding line of the aluminum-scandium alloy target. The vacuum suspension melting process involves the addition of aluminum and / or scandium to adjust the element ratio; The temperature of the vacuum suspension melting is 1550-1650℃; The vacuum suspension melting time is 40-80 minutes; The absolute vacuum degree of the vacuum suspension melting is 0.01-0.05 Pa; The recycling method yields aluminum-scandium alloy ingots with a purity ≥ 99.99 wt%.

2. The recycling method according to claim 1, characterized in that, The ultrasonic cleaning solution used includes alkaline or acidic solutions.

3. The recycling method according to claim 2, characterized in that, The alkaline solution includes sodium hydroxide solution and / or potassium hydroxide solution.

4. The recycling method according to claim 2, characterized by, The concentration of the alkaline solution is 10-20 wt%.

5. The recycling method according to claim 2, characterized in that, The acid solution includes any one or a combination of at least two of the following: nitric acid solution, hydrochloric acid solution, sulfuric acid solution, or hydrofluoric acid solution.

6. The recycling method according to claim 2, characterized by, The concentration of the acid solution is 4-8 wt%.

7. The recycling method of claim 1, wherein, The ultrasonic cleaning frequency is 20-40kHz.

8. The recycling method of claim 1, wherein, The ultrasonic cleaning time is 30-60 minutes.

9. The recycling method of claim 1, wherein, The ultrasonic cleaning and drying process also includes a deionized water rinse.

10. The recycling method of claim 1, wherein, The drying process includes hot air circulation drying.

11. The recycling method according to claim 10, characterized in that, The temperature of the hot air circulation drying is 40-80℃.

12. The recycling method of claim 10, wherein, The hot air circulation drying time is 30-60 minutes.

13. The recycling method of claim 1, wherein, The aluminum-scandium alloy ingot is used to prepare aluminum-scandium alloy targets and / or aluminum-scandium alloy backplates.

14. The recycling method of claim 1, wherein, The recycling method includes the following steps: (1) Pretreatment: Select an aluminum-scandium alloy target with a scandium content of 5-50wt%, and machine the aluminum-scandium alloy target to remove the back plate. The machining position is 1-5mm lower than the welding line of the aluminum-scandium alloy target. Cut the aluminum-scandium alloy target after removing the back plate into aluminum-scandium alloy blocks, and the longest side of the aluminum-scandium alloy blocks is ≤5cm. (2) Surface impurity removal: The obtained aluminum-scandium alloy block is subjected to ultrasonic cleaning, deionized water rinsing, and hot air circulation drying in sequence; the cleaning solution used for ultrasonic cleaning includes alkaline solution or acid solution; the alkaline solution includes sodium hydroxide solution and / or potassium hydroxide solution, and the concentration is 10-20wt%; the acid solution includes any one or at least two of nitric acid solution, hydrochloric acid solution, sulfuric acid solution or hydrofluoric acid solution, and the concentration is 4-8wt%; the ultrasonic cleaning frequency is 20-40kHz, the time is 30-60min, and the cleaning process is accompanied by rotational shearing treatment; the temperature of the hot air circulation drying is 40-80℃, and the time is 30-60min; (3) Vacuum suspension melting: The aluminum-scandium alloy block after surface impurity removal is placed in a melting crucible and vacuum suspended at 1550-1650℃ for 40-80 min, including at least 2 melting processes, and the absolute vacuum degree of melting is 0.01-0.05 Pa. During the melting process, aluminum and / or scandium are added to adjust the element ratio, and finally aluminum-scandium alloy ingots with a purity ≥99.99wt% are obtained. The obtained aluminum-scandium alloy ingots are subsequently used to prepare aluminum-scandium alloy targets and / or aluminum-scandium alloy backplates.