Method for recycling target material

Abstract

The application belongs to the technical field of resource recycling and utilization, and particularly discloses a target material recycling method, which comprises the following steps: etching curve analysis on the sputtered target material; determining a target material area to be recycled according to the etching curve; linear cutting the target material area to be recycled according to the size requirement of the finished target material, to obtain a target material block; and processing the sputtering channel of the target material block to be flat, to obtain the finished target material. The sputtered target material can be directly processed into the finished target material that can be recycled, so that the production cost of the target material is reduced.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of resource recycling and utilization, and particularly relates to a target material recycling method. BACKGROUND

[0002] The target blank and the back plate with certain strength are combined to form a target assembly. The back plate can provide support for the sputtering target and has a conduction effect. The target blank and the back plate are usually welded to form a shape.

[0003] After the target material is used for sputtering, the surface of the target material is affected by the magnetic field of the sputtering machine, and a sputtering channel is formed on the surface of the target material. Due to the characteristics of the magnetic field distribution, the sputtering channel presents a ring-shaped wave shape. When the maximum depth of the sputtering channel exceeds a limited value, the target material will be broken if it is continuously used. Therefore, the use of the target material needs to be stopped at this time. At present, the utilization rate of the target material is relatively low, generally about 30-50%, and a large part of the material of the sputtered target material after use has not been effectively utilized.

[0004] The patent document with the application number CN202210914816.X discloses a recycling method of a sputtering target assembly. The sputtering target assembly is separated by a physical separation method to obtain a back plate and a sputtering target. The sputtering target is then subjected to alkaline immersion, acid immersion, water washing, drying, smelting, standing, and casting to obtain a metal ingot. The recycling method has a long process flow and consumes a large amount of materials and energy.

[0005] The patent document with the application number CN201811022654.9 discloses a sputtering target recycling method. The target material and the back plate are separated by a turning method and a chemical method. Although this method can effectively recycle the target material, the processing cost is high, the back plate turning chips generated contain impurities such as turning fluid, resulting in low recycling value, and the overall recycling process is long, which is not conducive to cost minimization.

[0006] At present, there is an urgent need for a low-cost, high-value-added target material recycling method. SUMMARY

[0007] The purpose of the present application is to provide a target material recycling method, which has low cost, high value-added, and does not involve chemical means and does not consume chemical materials.

[0008] To achieve the above purpose, the following specific technical solutions are adopted.

[0009] The target material recycling method comprises the following steps:

[0010] Performing etching curve analysis on the sputtered target material; determining the target material area to be recycled according to the etching curve;

[0011] According to the size requirement of the finished target material, the target material to be recycled is cut to obtain a target material block;

[0012] The sputtering channel of the target material block is processed to obtain a finished target material.

[0013] Further, as a preferred solution, the target material after sputtering is cut to remove the part of the back plate edge without target blank welding, and the welding boundary is exposed.

[0014] Further, as a preferred solution, the wire cutting method is medium wire cutting.

[0015] Further, as a preferred solution, it also includes processing the target material block to the required thickness of the finished target material. Further preferably, the processing method is turning or grinding.

[0016] Further, as a preferred solution, it also includes analyzing the metal content of the sputtering surface of the finished target material.

[0017] Further, as a preferred solution, the target material is an aluminum scandium target material.

[0018] Compared with the prior art, the present application has the following obvious beneficial effects:

[0019] (1) The target material after sputtering can be directly processed into a finished target material that can be reused, reducing the production cost of the target material;

[0020] (2) The target material does not need to be re-melted and cast during the recycling process;

[0021] (3) Low recycling cost, simple process flow and easy operation. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 It is a target material recycling process flowchart for the embodiment.

[0023] Figure 2 It is a schematic diagram of the aluminum scandium target assembly structure.

[0024] Figure 3 It is the appearance of the aluminum scandium target after sputtering in Example 1.

[0025] Figure 4 It is the etching curve of the aluminum scandium target after sputtering in Example 1.

[0026] Figure 5 It is an etching curve analysis diagram of Example 1.

[0027] Figure 6 It is a cutting process site picture.

[0028] Figure 7 It is a micro-morphology diagram of the target material welding boundary layer.

[0029] Figure 8 Figure 2 is a side view of a target material after water cutting.

[0030] Figure 9 Figure 3 is an etching curve of the aluminum scandium target material after sputtering in Example 2.

[0031] Figure 10 Figure 4 is an etching curve of the aluminum scandium target material after sputtering in Example 3. DETAILED DESCRIPTION

[0032] In order to facilitate the understanding of the present application, the following will make a more comprehensive and detailed description of the present application in combination with the drawings and preferred embodiments of the specification, but the protection scope of the present application is not limited to the following specific embodiments.

[0033] Unless otherwise defined, all the professional terms used in the following have the same meaning as that generally understood by those skilled in the art. The professional terms used in the present application are only for the purpose of describing the specific embodiments and are not intended to limit the protection scope of the present application.

[0034] Unless otherwise specified, various raw materials, reagents, instruments and equipment used in the present application can be purchased from the market or can be prepared by existing methods.

[0035] Take the recycling of aluminum scandium target material as an example.

[0036] The recycling process flow chart of the target material is shown in Figure 1. Figure 1

[0037] Figure 2 Figure 2 is a schematic diagram of the aluminum scandium target material assembly structure, wherein 1 is a target blank, and 2 is a back plate. The target blank and the back plate are combined together by diffusion welding, and the back plate is a "concave" structure. Generally, the size of the target material is 332x7mm, and the depth of the back plate groove is 2-5mm.

[0038] According to the maximum depth of the sputtering channel of the target material after sputtering, the size of the finished target material can be roughly divided into the following three types.

[0039] Table 1: Correspondence between the maximum depth of the sputtering channel and the size of the finished target material

[0040]

[0041] Example 1

[0042] The size of the target blank is 332x7mm, and the depth of the back plate groove is 2mm. The Sc content of the aluminum scandium target material is 20±0.3at%.

[0043] Figure 3 ​The appearance of the aluminum scandium target after sputtering in Example 1. After the target is used for sputtering, the surface is affected by the magnetic field of the sputtering machine, and a sputtering channel is formed on the surface of the target. Due to the characteristics of the magnetic field distribution, the sputtering channel presents a ring-shaped undulating shape.

[0044] Figure 4 The etching curve of the aluminum scandium target after sputtering in Example 1. When the maximum depth of the sputtering channel exceeds the specified value, the target will be broken if it is used continuously, so the use of the target needs to be stopped. From the etching curve, it can be seen that the target with a thickness of 7 mm is used most in the area near the diameter of 240 mm after sputtering, and the deepest position of the sputtering channel still has about 0.9 mm of un-sputtered area, and there is a risk of breaking the target if it is used continuously; in the range of about 85 mm in diameter, it is the second sputtering track, and there is about 4 mm of un-sputtered area, and the diameter range at this depth is 190 mm. Adding the back plate groove of 2 mm, the actual thickness of the target blank is about 6 mm, and the diameter range of the target blank is 190 mm. Figure 3

[0045] Figure 5 The etching curve analysis diagram.

[0046] The target is processed by water cutting, and the outer diameter of the cut circular target is set to 330 mm; the feed rate is 60%; after water cutting, the side appearance of the target is as shown in Figure 7 , it can be seen that there are obvious welding lines between the target and the back plate. The outer diameter of the assembly of the target blank and the back plate is 329 mm, and the thickness is 18 mm.

[0047] Figure 6 The cutting process site picture.

[0048] Figure 7 The microstructure of the target welding interface layer, the lower part is the grain morphology of the aluminum scandium alloy, and the microstructure of the welding layer of the target and the back plate can be clearly understood.

[0049] Figure 8 The side appearance of the target after water cutting.

[0050] ​The direction mark is made on the target side with "↑", and the "↑" points to the sputtering surface of the target. The depth of 1 mm is cut along the welding line near the back plate side; after cutting, the thickness of the target is 9.8 mm. The target after wire cutting is machined, and the back plate side is machined to remove the residual back plate part on the target welding surface. The machining parameters are: spindle speed: 500 r / min, feed amount: 0.3 mm, feed speed: 0.15 mm / r; after removing 0.8 mm, the residual back plate material is removed by visual inspection, and the thickness of the target is currently 9.0 mm. Then the sputtering surface of the target is machined, and the machining parameters are: spindle speed: 500 r / min, feed amount: 0.1 mm, feed speed: 0.05 mm / r; after removing 3.0 mm, the target within the range of 190 mm in diameter has been machined to be flat, and the last turning material is taken during the process, and the thickness of the target is currently 6.0 mm. Then the target is cut by wire cutting to obtain a circular target with a size of 185 mm, and finally the circular target is machined to the finished product size of 180x5 mm.

[0051] The turning material taken during the turning process is sent for Sc content inspection, and the Sc content of the target is: 20.2 at%. The results show that the Sc content meets the product requirements, and the finished target can be obtained by recycling the scrapped target.

[0052] Example 2

[0053] The size specification of the target blank is 332x7mm, and the back plate groove depth is 2mm. The Sc content of the aluminum scandium target is 20±0.3at%.

[0054] First, the sputtered target is etched for curve analysis, and the results are shown in Figure 9 From the Figure 9 it can be seen that: after the target is used for sputtering, the sputtering channel presents a ring-shaped undulating shape. The target with a thickness of 7 mm is used most after sputtering in the area near the diameter of 240 mm, and the deepest position of the sputtering channel still has about 3.3 mm of un-sputtered; the second sputtering track is near the diameter range of 85 mm, and there is about 5 mm of un-sputtered at this position, and the diameter range of the depth at this position is 200 mm. Adding the 2 mm of the back plate concave layer, the actual thickness of the target blank is more than 6 mm, and the diameter range of the target blank with an actual thickness of more than 5 mm is 332 mm.

[0055] The target is water cut, and the outer diameter of the cut circular target is set to: 310 mm; the feed rate is 40%; after water cutting, the outer diameter of the target and the back plate assembly is 309 mm, and the thickness is 18 mm.

[0056] The direction mark is made on the target side with "↑", and the "↑" points to the sputtering surface of the target. The depth of 2 mm is cut along the welding line near the back plate side; after cutting, the thickness of the target is 10.5 mm. The target after wire cutting is machined, and the back plate side is machined to the end face. The machining parameters are: spindle speed: 500 r / min, feed amount: 0.3 mm, feed speed: 0.15 mm / r; after removing 0.6 mm, the thickness of the target is 9.9 mm. Then the sputtering surface of the target is machined, and the machining parameters are: spindle speed: 500 r / min, feed amount: 0.1 mm, feed speed: 0.05 mm / r; after removing 3.8 mm, the sputtering channel of the target is machined to be flat, and the last turning material is obtained during the process, and the thickness of the target is 6.1 mm. Then the outer diameter and the welding surface of the target are machined to the finished size of 304x5.98 mm.

[0057] The welding surface side of the target blank contains 0.5-0.8 mm of aluminum alloy back plate material, and the welding surface side of the target blank is bound with oxygen-free copper back plate by indium binding, and the binding rate is 99.6%; the binding layer has an aluminum alloy composite layer of 0.5-0.8 mm in addition to the indium layer, which does not affect the actual application of the back end of the target during the use of the target.

[0058] The turning material obtained during the turning process is sent for Sc content inspection, and the Sc content of the target is 20.2 at%. The results show that the Sc content meets the product requirements, and the finished target can be obtained by recycling the scrapped target.

[0059] Example 3

[0060] The size specification of the target blank is 332x7 mm, and the back plate groove depth is 2 mm. The Sc content of the aluminum scandium target is 9.6±0.3 at%.

[0061] First, the sputtered target is etched for curve analysis, as shown in Figure 10 From Figure 10 it can be seen that: the target blank with a thickness of 7 mm is used most in the area near the diameter of 240 mm after sputtering, and there is about 5.5 mm of un-sputtered target left at the deepest position of the sputtering channel; the second sputtering track is near the diameter of 85 mm, and there is about 6 mm of un-sputtered target left at this position, and the diameter range of the depth at this position is 206 mm; plus the 2 mm of the back plate groove, the actual thickness of the target blank is 6 mm or more, and the diameter range of the target blank is 332 mm.

[0062] The target is processed by water cutting, and the outer diameter of the circular target is set to 310 mm; the feed rate is 40%; after water cutting, the outer diameter of the target and the back plate assembly is 309 mm, and the thickness is 18 mm.

[0063] The direction mark is made on the target side with "↑", and the "↑" points to the sputtering surface of the target. The depth of 0.5 mm on the side close to the back plate along the welding line is subjected to the medium wire cutting; after the cutting, the thickness of the target is 9.5 mm. The target after the wire cutting is subjected to the turning processing, and the back plate side is processed to the end surface flat. The processing parameters are as follows: spindle speed: 500 r / min, feed amount: 0.3 mm, and feed speed: 0.15 mm / r; after 0.8 mm is removed by processing, the thickness of the target is 8.7 mm. Then the sputtering surface of the target is subjected to the machining, and the turning processing parameters are as follows: spindle speed: 500 r / min, feed amount: 0.1 mm, and feed speed: 0.05 mm / r; after 2.3 mm is removed by processing, the sputtering channel of the target is processed to be flat, and the turning material of the last pass is obtained in the process, and the thickness of the target is 6.4 mm. Then the outer diameter and the side of the welding surface of the target are processed, and the back plate material is completely removed by processing, and the product size is 304*5.98 mm.

[0064] The side of the welding surface of the target blank is bound with the oxygen-free copper back plate by indium binding, and the binding rate is 99.8%; the turning material obtained in the turning process is subjected to the Sc content inspection, and the Sc content of the target is 9.8 at%. The results show that the Sc content meets the product requirements, and the finished target material recycled from the scrapped target material can be obtained.

[0065] The sputtering channel data of the target material of Example 1-3 and the size analysis data of the recyclable material are shown in Table 2 and Table 3, respectively.

[0066] Table 2

[0067]

[0068] Table 3

[0069]

[0070] The above only describes the preferred embodiments of the present application, and it should be noted that the ordinary skilled in the art can make several improvements and refinements without departing from the principles of the present application, and these improvements and refinements should also be considered as the protection scope of the present application.

Claims

1. A method of recycling a target material, characterized by, After the target material is used for sputtering, a sputtering channel is formed on the surface of the target material, the sputtering channel presents a circular wave shape, and the sputtering channel comprises: Performing etching curve analysis on the sputtered target material; determining a target material area to be recovered according to the etching curve; Determining the size of a finished round target material according to the maximum depth of the sputtering channel of the sputtered target material; linearly cutting the target material area to be recovered to obtain a target material block according to the size of the finished round target material; Processing the sputtering channel of the target material block to be flat to obtain the finished round target material.

2. The method of recycling a target material according to claim 1, wherein Cutting the sputtered target material to remove the part of the back plate edge without target blank welding, and exposing the welding boundary.

3. The method of recycling a target material according to claim 1, wherein The linear cutting mode is middle wire cutting.

4. The method of recycling a target material according to any one of claims 1 to 3, wherein Further comprising: Processing the target material block to the thickness required by the finished round target material.

5. The method of recycling a target material according to claim 4, wherein The processing mode is turning or grinding.

6. The method of recycling a target material according to any one of claims 1 to 3, wherein Further comprising: Analyzing the metal content of the sputtering surface of the finished round target material.

7. The method of recycling a target material according to any one of claims 1 to 3, wherein The target material is an aluminum scandium target material.

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