Welding method for aluminum-containing target material

Abstract

The invention provides a welding method of an aluminum-containing target material, which comprises the following steps: cleaning and drying the aluminum-containing target material and a back plate with threads on the welding surfaces, and then fitting the welding surfaces of the aluminum-containing target material and the back plate for vacuum packaging to obtain an assembled target material assembly; and the assembled target material assembly is placed on a machining platform of a hydraulic device, a pressing block is placed above the target material assembly, the pressure gradient of the hydraulic device is set to be increased, pressure maintaining is conducted under the pressure condition of each stage, the pressure is removed after pressurization is completed, and the welded aluminum-containing target material is obtained. According to the method, a hydraulic welding mode is adopted, the threads are arranged on the back plate, so that the contact area of the welding surfaces of the target material and the back plate is increased when the target material and the back plate are combined and welded, and the target material and the back plate are gradually deformed through a gradient pressurization mode, so that the situation that deformation is too large due to one-time application of too large pressure is avoided; the welding strength of the target material assembly can be effectively improved, meanwhile, operation can be simplified, the production efficiency is improved, and the machining cost is saved.

Description

Technical Field

[0001] The invention belongs to the technical field of target material processing and relates to a welding method for an aluminum-containing target material. Background Art

[0002] With the rapid development of semiconductor technology, target materials, as the basic raw materials in the semiconductor field, have been increasingly widely used, and the quality of target materials will directly affect the quality of the coating after sputtering. At present, sputtering targets are usually components connected by target blanks and backing plates, and welding process is the key technology for connecting target materials. Under the existing sputtering technology, the working conditions of the target assembly are harsh. During sputtering, one side of the target is in high-temperature vacuum conditions and is bombarded by various particles in high-voltage electric fields and strong magnetic fields, generating a large amount of heat. The backing plate is cooled by cooling water, thus forming a huge temperature difference and pressure difference on both sides of the target assembly. Therefore, there are strict requirements on the welding quality of the target assembly, which requires not only good thermal conductivity of the welding part, but also a certain strength of the weld. Otherwise, it is easy to cause deformation and cracking of the target material, affecting the film quality and even causing damage to the sputtering machine.

[0003] At present, the commonly used target material welding methods include brazing, diffusion welding, and pressure welding. Among them, brazing mainly uses relatively soft indium, tin and their alloy solders for welding, but the welding strength is usually low; diffusion welding requires hot isostatic pressing, which requires high temperature and pressure, high energy consumption, and long time; hydraulic welding is a type of pressure welding method, which refers to the use of hydraulic transmission oil or engine oil as a medium to press two separate materials into a whole to obtain a certain bonding strength. This method is usually simpler and can greatly improve processing efficiency, reduce welding costs, and ensure welding strength.

[0004] CN 106766869A discloses a novel target furnace device and a target binding method. A furnace door is arranged on one side of the furnace body, a heating base is arranged in the furnace body, a heating device and a temperature detector for temperature control are arranged in the heating base, a target substrate for placing the target is connected to the heating base, a pressure plate is arranged directly above the target substrate, the upper end of the pressure plate is connected to a hydraulic pump outside the furnace body, and the furnace body is connected to an external vacuum pump. The device and method still adopt the solder welding method, and the combination between the target and the substrate is ensured by heating and pressurizing, rather than independently adopting the pressure welding method, and the scope of application is limited.

[0005] CN 112453623A discloses a method for welding and shaping integration of a circular titanium target and a back plate, the method comprising: infiltrating the welding surface of the circular titanium target and the welding surface of the back plate with molten solder, and fitting the welding surfaces of the two, and the circular titanium target is located above the back plate; placing a pad block above the circular titanium target, and performing a pressurizing operation above the pad block; removing the pressurizing operation after cooling to obtain a circular titanium target assembly. Although the method uses a pressurizing operation to improve the welding strength of the target and the back plate, it is still mainly based on brazing, rather than an improvement made for the case of using pressure welding alone.

[0006] CN 104625389A discloses a welding method for an aluminum alloy sputtering target for integrated circuit packaging materials, the method comprising: machining convex teeth of a certain shape and size on the welding surface of the target, machining corresponding grooves on the back plate, assembling and combining the target and the back plate, placing them in a package for vacuum sealing, and then using a hot isostatic pressing method to completely fill the groove with the material, and connecting the target and the back plate. The method is mainly based on hot isostatic pressing, and the required parameters such as temperature and pressure are relatively high, the process steps are complex, the processing efficiency is low, the equipment requirements are high, and it is not conducive to the cost control of batch products.

[0007] In summary, for the welding process of the target assembly, hydraulic welding is adopted, and the welding strength of the target assembly is improved by improving the welding surface structure, and the requirements of simple processing technology and low cost are met. Summary of the invention

[0008] In view of the problems existing in the prior art, the purpose of the present invention is to provide a welding method for an aluminum-containing target material, which adopts hydraulic welding to weld the aluminum-containing target material and a back plate, and improves the welding strength of the target material and the back plate by controlling the welding process, and improves the processing efficiency of the target material welding, simplifies the operation steps, and reduces energy consumption and processing costs.

[0009] To achieve this object, the present invention adopts the following technical solutions:

[0010] The present invention provides a welding method for an aluminum-containing target material, the welding method comprising the following steps:

[0011] (1) cleaning and drying the aluminum-containing target material and the backing plate with threads on the welding surface, and then laminating the welding surfaces of the two and vacuum packaging them to obtain an assembled target material assembly;

[0012] (2) placing the target assembly assembled in step (1) on a processing platform of a hydraulic device, and placing a pressure block above the target assembly, setting the pressure gradient of the hydraulic device to increase, maintaining the pressure under each pressure level, and releasing the pressure after the pressurization is completed to obtain an aluminum-containing target after welding.

[0013] In the present invention, for the welding of the target material assembly, based on the advantages and disadvantages of the existing welding process, the present invention adopts a hydraulic welding method, by arranging threads on the back plate, so that the contact area between the target material and the welding surface of the back plate is increased when the two are welded in combination, and by a gradient pressurization method, the target material and the back plate are gradually deformed to avoid damage to the target material caused by excessive deformation due to excessive pressure applied at one time; through the above-mentioned control of the hydraulic welding process, the welding strength of the target material assembly can be effectively improved to meet the use requirements of the target material, and at the same time, the production efficiency can be improved and the processing cost can be saved; the method is simple to operate, the required energy consumption and cost are low, and the scope of application is wide.

[0014] The following are preferred technical solutions of the present invention, but are not intended to be limitations of the technical solutions provided by the present invention. Through the following technical solutions, the technical objectives and beneficial effects of the present invention can be better achieved and realized.

[0015] As a preferred technical solution of the present invention, the aluminum-containing target material in step (1) includes a high-purity aluminum target material or an aluminum alloy target material.

[0016] Preferably, the purity of the high-purity aluminum target is above 99.99wt%, for example, 99.99wt%, 99.992wt%, 99.995wt%, 99.997wt%, 99.999wt% or 99.9995wt%, etc., but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0017] Preferably, the aluminum content in the aluminum alloy target is 95-99.9wt%, for example, 95wt%, 95.5wt%, 96wt%, 96.5wt%, 97wt%, 97.5wt%, 98wt%, 98.5wt%, 99wt%, 99.5wt% or 99.9wt%, etc., but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0018] As a preferred technical solution of the present invention, the back plate in step (1) is made of aluminum alloy. The material of the back plate is similar to that of the target material to facilitate welding of the two, but its strength, hardness and other properties are better than those of the target material to play a supporting and protective role of the back plate. The selectable aluminum alloy types include A2024, A7075, A6061, etc.

[0019] Preferably, the threads on the welding surface of the back plate in step (1) are distributed in concentric circles.

[0020] Preferably, the width of the thread is 1.5 to 2.5 mm, for example, 1.5 mm, 1.6 mm, 1.8 mm, 2.0 mm, 2.2 mm, 2.4 mm or 2.5 mm, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable; the depth of the thread is 1.0 to 1.5 mm, for example, 1.0 mm, 1.1 mm, 1.2 mm, 1.3 mm, 1.4 mm or 1.5 mm, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0021] As a preferred technical solution of the present invention, the cleaning in step (1) is carried out using an organic solvent, and the organic solvent includes any one of isopropyl alcohol, isopropyl alcohol or ethanol, or a combination of at least two of them. Typical but non-limiting examples of the combination include: a combination of isopropyl alcohol and isopropyl alcohol, a combination of isopropyl alcohol and ethanol, a combination of isopropyl alcohol, isopropyl alcohol and ethanol, and the like.

[0022] Preferably, the cleaning method in step (1) includes ultrasonic cleaning.

[0023] Preferably, the cleaning time in step (1) is 3 to 8 minutes, for example 3 minutes, 4 minutes, 5 minutes, 6 minutes, 7 minutes or 8 minutes, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0024] Preferably, the drying method in step (1) includes vacuum drying.

[0025] Preferably, the vacuum drying temperature is 70-80°C, for example, 70°C, 72°C, 74°C, 75°C, 76°C, 78°C or 80°C, etc., the pressure is below 0.1Pa, for example, 0.1Pa, 0.08Pa, 0.06Pa, 0.05Pa, 0.04Pa, 0.02Pa or 0.01Pa, etc., and the time is 0.5-1h, for example, 0.5h, 0.6h, 0.7h, 0.75h, 0.8h, 0.9h or 1h, etc.; but it is not limited to the listed values, and other unlisted values ​​within the respective numerical ranges are equally applicable.

[0026] As a preferred technical solution of the present invention, the vacuum packaging method in step (1) is vacuum plastic packaging.

[0027] Preferably, the plastic sealing material used for the vacuum plastic packaging includes any one of polyethylene (PE), polyethylene terephthalate (PET) or polyvinyl chloride (PVC) or a combination of at least two of them. Typical but non-limiting examples of the combination include: a combination of polyethylene and polyethylene terephthalate, a combination of polyethylene terephthalate and polyvinyl chloride, a combination of polyethylene, polyethylene terephthalate and polyvinyl chloride, etc.

[0028] Preferably, the vacuum packaging is performed to a pressure of less than 500Pa, for example, 500Pa, 450Pa, 400Pa, 350Pa, 300Pa, 250Pa, 200Pa or 100Pa, etc., but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0029] In the present invention, the target material and the back plate are assembled by vacuum plastic packaging and then hydraulically welded, which can reduce the holes formed by residual air between the bonding surfaces after the threads bite into the target material and improve the bonding rate of the target material and the back plate.

[0030] As a preferred technical solution of the present invention, when the target assembly is placed in step (2), the aluminum-containing target is located at the top.

[0031] Preferably, the shape and size of the compact match the shape and size of the aluminum-containing target.

[0032] Preferably, the pressing block is made of aluminum alloy.

[0033] In the present invention, the material of the pressing block is also selected from aluminum alloy, which tends to be lightweight and has considerable strength. The size of the pressing block needs to cover the entire surface of the target material to prevent the target material from only being partially deformed and sunken when pressurized. If the pressing block is made of a high-density material, its weight is too large and is not conducive to transportation. For example, the material that can be selected is A6061.

[0034] As a preferred technical solution of the present invention, the hydraulic device in step (2) includes a hydraulic press.

[0035] Preferably, the component on the hydraulic press that is in direct contact with the pressing block is a pressing head, and the pressing head moves up and down.

[0036] As a preferred technical solution of the present invention, the pressure applied by the hydraulic device to the pressing block increases from 20t to 90-110t, for example, 90t, 92t, 95t, 96t, 100t, 105t, 108t or 110t, etc., with an increasing gradient of 15-25t, for example, 15t, 16t, 17t, 18t, 19t, 20t, 21t, 22t, 23t, 24t or 25t, etc., but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0037] In the present invention, a gradient step-by-step pressurization method is adopted. After each pressurization, there will be a certain degree of work hardening, so the pressure needs to be gradually increased, which can also avoid the problem of excessive deformation caused by applying too much pressure at one time.

[0038] Preferably, the holding time at each level of pressure is 10 to 60 s, for example 10 s, 15 s, 20 s, 30 s, 40 s, 45 s, 50 s or 60 s, etc., but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0039] Preferably, the holding time when the pressure is less than 60t is 10 to 30s, for example, 10s, 15s, 20s, 25s or 30s, etc., but is not limited to the listed values, and other unlisted values ​​within the numerical range are equally applicable; the holding time when the pressure is greater than 60t is 30 to 60s, for example, 30s, 35s, 40s, 45s, 50s, 55s or 60s, etc., but is not limited to the listed values, and other unlisted values ​​within the numerical range are equally applicable.

[0040] Preferably, the downward pressure amount during the holding time of each level of pressure is measured and recorded.

[0041] As a preferred technical solution of the present invention, after the pressurization is completed, the pressure is directly removed, the vacuum packaging is removed, and the welding of the target assembly is completed.

[0042] Preferably, the target assembly after welding is inspected to check its bonding properties and whether there are gaps at the welding surface.

[0043] As a preferred technical solution of the present invention, the welding method comprises the following steps:

[0044] (1) cleaning and drying an aluminum-containing target and a backing plate with threads on the welding surface, wherein the aluminum-containing target comprises a high-purity aluminum target or an aluminum alloy target, wherein the purity of the high-purity aluminum target is 99.99wt% or more, and the aluminum content of the aluminum alloy target is 95-99.9wt%. The backing plate is made of an aluminum alloy, and the threads on its welding surface are distributed in concentric circles, the width of the threads is 1.5-2.5mm, and the depth of the threads is 1.0-1.5mm. The cleaning is performed with an organic solvent, and the cleaning method comprises ultrasonic cleaning, and the cleaning time is 3-8min. The drying method comprises vacuum drying, and the vacuum drying temperature is 70-80°C, the pressure is below 0.1Pa, and the time is 0.5-1h. Then, the welding surfaces of the two are laminated and vacuum-sealed. The plastic sealing material comprises any one of polyethylene, polyethylene terephthalate, or polyvinyl chloride, or a combination of at least two thereof. During the vacuum packaging, the pressure is evacuated to below 500Pa to obtain an assembled target assembly;

[0045] (2) placing the target assembly assembled in step (1) on a processing platform of a hydraulic device, wherein the aluminum-containing target is located at the top when the target assembly is placed, and placing a pressure block on the top of the target assembly, wherein the shape and size of the pressure block match the shape and size of the aluminum-containing target, and the material of the pressure block is an aluminum alloy, and the hydraulic device comprises an oil hydraulic press, wherein the component on the oil hydraulic press that is in direct contact with the pressure block is a pressure head, and the pressure head moves up and down, and the pressure gradient of the hydraulic device is set to increase, and the pressure applied by the hydraulic device to the pressure block increases from 20t to 90-110t, and the increase gradient is 15-25t, and the pressure is maintained under each level of pressure, and the pressure maintenance time under each level of pressure is 10-60s, the pressure maintenance time when the pressure is less than 60t is 10-30s, and the pressure maintenance time when the pressure is greater than 60t is 30-60s, and the downward pressure within the pressure maintenance time of each level of pressure is measured and recorded, and the pressure is directly released after the pressurization is completed, and the vacuum packaging is removed to obtain the aluminum-containing target after welding.

[0046] Compared with the prior art, the present invention has the following beneficial effects:

[0047] (1) The method of the present invention adopts a hydraulic welding method, by providing threads on the back plate, so that the contact area between the target material and the welding surface of the back plate is increased when the two are welded together, and the target material and the back plate are gradually deformed by gradient pressure, so as to avoid excessive deformation caused by applying too much pressure at one time and causing damage to the target material;

[0048] (2) The present invention can effectively improve the welding strength of the target assembly by controlling the hydraulic welding process and parameters, so that it meets the use requirements of the target material, and can also improve production efficiency and save processing costs;

[0049] (3) The method of the present invention is easy to operate, requires low energy consumption and cost, and has a wide range of applications. DETAILED DESCRIPTION

[0050] In order to better illustrate the present invention and facilitate understanding of the technical solution of the present invention, the present invention is further described in detail below. However, the following embodiments are only simple examples of the present invention and do not represent or limit the scope of protection of the present invention. The scope of protection of the present invention shall be subject to the claims.

[0051] The specific implementation method of the present invention provides a welding method for an aluminum-containing target material, and the welding method comprises the following steps:

[0052] (1) cleaning and drying the aluminum-containing target material and the backing plate with threads on the welding surface, and then laminating the welding surfaces of the two and vacuum packaging them to obtain an assembled target material assembly;

[0053] (2) placing the target assembly assembled in step (1) on a processing platform of a hydraulic device, and placing a pressure block above the target assembly, setting the pressure gradient of the hydraulic device to increase, maintaining the pressure under each pressure level, and releasing the pressure after the pressurization is completed to obtain an aluminum-containing target after welding.

[0054] The following are typical but non-limiting embodiments of the present invention:

[0055] Embodiment 1:

[0056] This embodiment provides a welding method for an aluminum-containing target material, the welding method comprising the following steps:

[0057] (1) cleaning and drying an aluminum-containing target and a back plate with threads on the welding surface, wherein the aluminum-containing target is a high-purity aluminum target with a purity of 99.99wt%, and the back plate is made of A2024 aluminum alloy, and the threads on the welding surface are distributed in concentric circles, the width of the threads is 2.0mm, and the depth of the threads is 1.2mm. The cleaning is performed using isopropyl alcohol, and the cleaning method includes ultrasonic cleaning for 5min. The drying method is vacuum drying, and the vacuum drying temperature is 75°C, the pressure is 0.1Pa, and the time is 0.75h. Then, the welding surfaces of the two are laminated and vacuum-sealed. The plastic sealing material used is polyethylene. The vacuum packaging is evacuated to a pressure of 500Pa to obtain an assembled target assembly;

[0058] (2) placing the target assembly assembled in step (1) on a processing platform of a hydraulic press, wherein the aluminum-containing target is located at the top when the target assembly is placed, and placing a pressing block on the target assembly, wherein the shape and size of the pressing block match the shape and size of the aluminum-containing target, and the pressing block is made of A6061 aluminum alloy; the component on the hydraulic press that is in direct contact with the pressing block is a pressing head, and the pressing head moves up and down, and the pressure gradient of the hydraulic press is set to increase, and the pressure applied by the hydraulic press to the pressing block increases from 20t to 100t, and the increasing gradient is 20t; the pressure is maintained at each level of pressure, and the pressure maintenance time is 20s when the pressure is 20t, 40t and 60t, and the pressure maintenance time is 45s when the pressure is 80t and 100t, and the pressure is directly released after the pressurization is completed, and the vacuum packaging is removed to obtain the welded aluminum-containing target.

[0059] In this embodiment, the above method is used to perform oil pressure welding of the target material and the back plate. After welding, there is basically no gap in the welding surface, the bonding rate reaches 99%, and the welding strength reaches 20 MPa.

[0060] Embodiment 2:

[0061] This embodiment provides a welding method for an aluminum-containing target material, the welding method comprising the following steps:

[0062] (1) cleaning and drying an aluminum-containing target and a back plate with threads on the welding surface, wherein the aluminum-containing target is a high-purity aluminum target with a purity of 99.995wt%, and the back plate is made of A2024 aluminum alloy, and the threads on the welding surface are distributed in concentric circles, the width of the threads is 1.5mm, and the depth of the threads is 1.0mm. The cleaning is performed using isopropyl alcohol, and the cleaning method includes ultrasonic cleaning for 3 minutes. The drying method is vacuum drying, and the vacuum drying temperature is 70°C, the pressure is 0.08Pa, and the time is 1h. Then, the welding surfaces of the two are laminated and vacuum-sealed. The plastic sealing material used is polyvinyl chloride. The vacuum packaging is evacuated to a pressure of 400Pa to obtain an assembled target assembly;

[0063] (2) placing the target assembly assembled in step (1) on a processing platform of a hydraulic press, wherein the aluminum-containing target is located at the top when the target assembly is placed, and placing a pressing block on the target assembly, wherein the shape and size of the pressing block match the shape and size of the aluminum-containing target, and the pressing block is made of A6061 aluminum alloy; the component on the hydraulic press that is in direct contact with the pressing block is a pressing head, and the pressing head moves up and down, and the pressure gradient of the hydraulic press is set to increase, and the pressure applied by the hydraulic press to the pressing block increases from 20t to 95t, and the increasing gradient is 15t; the pressure is maintained at each level of pressure, and the pressure maintenance time is 30s when the pressure is 20t, 35t and 50t, and the pressure maintenance time is 40s when the pressure is 65t, 80t and 95t, and the pressure is directly released after the pressurization is completed, and the vacuum packaging is removed to obtain the aluminum-containing target after welding.

[0064] In this embodiment, the above method is used to perform oil pressure welding of the target material and the back plate. After welding, there is basically no gap in the welding surface, the bonding rate reaches 98%, and the welding strength reaches 18 MPa.

[0065] Embodiment 3:

[0066] This embodiment provides a welding method for an aluminum-containing target material, the welding method comprising the following steps:

[0067] (1) cleaning and drying an aluminum-containing target material and a back plate with threads on the welding surface, wherein the aluminum-containing target material is an aluminum-copper alloy target material, the aluminum content in the aluminum alloy target material is 99.5wt%, and the back plate is made of A2024 aluminum alloy, the threads on the welding surface are distributed in concentric circles, the width of the threads is 2.5mm, and the depth of the threads is 1.5mm. The cleaning is performed using ethanol, and the cleaning method includes ultrasonic cleaning, the cleaning time is 8min, and the drying method is vacuum drying, the vacuum drying temperature is 80°C, the pressure is 0.05Pa, and the time is 0.5h, and then the welding surfaces of the two are laminated and vacuum-sealed. The plastic sealing material used is polyethylene terephthalate, and the vacuum packaging is evacuated to a pressure of 450Pa to obtain an assembled target assembly;

[0068] (2) placing the target assembly assembled in step (1) on a processing platform of a hydraulic press, wherein the aluminum-containing target is located at the top when the target assembly is placed, and placing a pressing block on the target assembly, wherein the shape and size of the pressing block match the shape and size of the aluminum-containing target, and the pressing block is made of A6061 aluminum alloy; the component on the hydraulic press that is in direct contact with the pressing block is a pressing head, and the pressing head moves up and down, and the pressure gradient of the hydraulic press is set to increase, and the pressure applied by the hydraulic press to the pressing block increases from 20t to 95t, and the increasing gradient is 25t; the pressure is maintained at each level of pressure, and the pressure holding time is 10s when the pressure is 20t and 45t, and the pressure holding time is 60s when the pressure is 70t and 95t, and the pressure is directly released after the pressurization is completed, and the vacuum packaging is removed to obtain the welded aluminum-containing target.

[0069] In this embodiment, the above method is used to perform oil pressure welding of the target material and the back plate. After welding, there is basically no gap in the welding surface, the bonding rate reaches 97%, and the welding strength reaches 20 MPa.

[0070] Embodiment 4:

[0071] This embodiment provides a welding method for an aluminum-containing target material, the welding method comprising the following steps:

[0072] (1) cleaning and drying an aluminum-containing target and a back plate with threads on the welding surface, wherein the aluminum-containing target is a high-purity aluminum target with a purity of 99.992wt%, and the back plate is made of A6061 aluminum alloy, and the threads on the welding surface are distributed in concentric circles, the width of the threads is 1.8mm, and the depth of the threads is 1.3mm. The cleaning is performed with isopropyl acetone, and the cleaning method includes ultrasonic cleaning for 6 minutes. The drying method is vacuum drying, and the vacuum drying temperature is 72°C, the pressure is 0.09Pa, and the time is 0.8h. Then, the welding surfaces of the two are laminated and vacuum-sealed. The plastic sealing material used is polyethylene. The vacuum packaging is evacuated to a pressure of 350Pa to obtain an assembled target assembly;

[0073] (2) placing the target assembly assembled in step (1) on a processing platform of a hydraulic press, wherein the aluminum-containing target is located at the top when the target assembly is placed, and placing a pressing block on the target assembly, wherein the shape and size of the pressing block match the shape and size of the aluminum-containing target, and the pressing block is made of A6082 aluminum alloy; the component on the hydraulic press that is in direct contact with the pressing block is a pressing head, and the pressing head moves up and down, and the pressure gradient of the hydraulic press is set to increase, and the pressure applied by the hydraulic press to the pressing block increases from 20t to 110t, and the increasing gradient is 18t; the pressure is maintained at each level of pressure, and the pressure maintenance time is 15s when the pressure is 20t, 38t and 56t, and the pressure maintenance time is 35s when the pressure is 74t, 92t and 110t, and the pressure is directly released after the pressurization is completed, and the vacuum packaging is removed to obtain the aluminum-containing target after welding.

[0074] In this embodiment, the above method is used to perform oil pressure welding of the target material and the back plate. After welding, there is basically no gap in the welding surface, the bonding rate reaches 98.5%, and the welding strength reaches 19.5 MPa.

[0075] Embodiment 5:

[0076] This embodiment provides a welding method for an aluminum-containing target material, the welding method comprising the following steps:

[0077] (1) cleaning and drying an aluminum-containing target and a back plate with threads on the welding surface, wherein the aluminum-containing target is an aluminum-magnesium alloy target, the aluminum content in the aluminum alloy target is 96wt%, and the back plate is made of A7075 aluminum alloy, the threads on the welding surface are distributed in concentric circles, the width of the threads is 2.2mm, and the depth of the threads is 1.4mm. The cleaning is performed using isopropyl alcohol, and the cleaning method includes ultrasonic cleaning, the cleaning time is 4min, and the drying method is vacuum drying, the vacuum drying temperature is 78°C, the pressure is 0.06Pa, and the time is 0.6h, and then the welding surfaces of the two are laminated and vacuum-sealed. The plastic sealing material used is polyvinyl chloride, and the vacuum packaging is evacuated to a pressure of 300Pa to obtain an assembled target assembly;

[0078] (2) placing the target assembly assembled in step (1) on a processing platform of a hydraulic press, wherein the aluminum-containing target is located at the top when the target assembly is placed, and placing a pressing block on the target assembly, wherein the shape and size of the pressing block match the shape and size of the aluminum-containing target, and the pressing block is made of A7075 aluminum alloy; the component on the hydraulic press that is in direct contact with the pressing block is a pressing head, and the pressing head moves up and down, and the pressure gradient of the hydraulic press is set to increase, and the pressure applied by the hydraulic press to the pressing block increases from 20t to 108t, and the increasing gradient is 22t; maintaining the pressure at each level of pressure, and the holding time when the pressure is 20t and 42t is 25s, and the holding time when the pressure is 64t, 86t, and 108t is 50s; after the pressurization is completed, the pressure is directly released, and the vacuum packaging is removed to obtain the welded aluminum-containing target.

[0079] In this embodiment, the above method is used to perform oil pressure welding of the target material and the back plate. After welding, there is basically no gap in the welding surface, the bonding rate reaches 99%, and the welding strength reaches 19.8 MPa.

[0080] Comparative Example 1:

[0081] This comparative example provides a welding method for an aluminum target material. The welding method refers to the method in Example 1, with the only difference being that the pressure applied by the hydraulic press in step (2) is increased to the maximum value at one time, and the holding time is the sum of the holding times of each level.

[0082] In this comparative example, when the target material is welded, the pressure applied by the hydraulic press is increased to the maximum at one time without a slow increase process in the middle. Excessive one-time pressure can easily cause excessive deformation of the target material, damage the target material, or even cause it to be scrapped. It may also cause an increase in internal defects and a decrease in the welding bonding rate to only about 85%. The welding is unqualified and needs to be reworked, which greatly increases the production cost.

[0083] From the above embodiments and comparative examples, it can be seen that the method of the present invention adopts hydraulic welding, and by setting threads on the back plate, the contact area between the target material and the welding surface of the back plate is increased when the two are welded in combination, and the target material and the back plate are gradually deformed by gradient pressurization to avoid damage to the target material caused by excessive deformation due to excessive pressure applied at one time; by controlling the hydraulic welding process and parameters, the welding strength of the target assembly can be effectively improved to meet the use requirements of the target material, and at the same time, the production efficiency can be improved and the processing cost can be saved; the method is easy to operate, the energy consumption and cost required are low, and the scope of application is wide.

[0084] The applicant declares that the present invention illustrates the detailed method of the present invention through the above-mentioned embodiments, but the present invention is not limited to the above-mentioned detailed method, that is, it does not mean that the present invention must rely on the above-mentioned detailed method to be implemented. Those skilled in the art should understand that any improvement of the present invention, equivalent replacement of the method of the present invention, addition of auxiliary steps, selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

Claims

1. A welding method for an aluminum target, characterized in that: The welding method comprises the following steps: (1) cleaning and drying the aluminum-containing target material and the backing plate with threads on the welding surface, and then laminating the welding surfaces of the two and vacuum packaging them to obtain an assembled target material assembly; (2) placing the target assembly assembled in step (1) on a processing platform of a hydraulic device, and placing a pressure block above the target assembly, setting the pressure gradient of the hydraulic device to increase, maintaining the pressure under each pressure level, and releasing the pressure after the pressurization is completed to obtain an aluminum-containing target after welding.

2. The welding method according to claim 1, characterized in that: The aluminum-containing target in step (1) comprises a high-purity aluminum target or an aluminum alloy target; Preferably, the purity of the high-purity aluminum target is above 99.99wt%; Preferably, the aluminum content in the aluminum alloy target is 95-99.9 wt %.

3. The welding method according to claim 1 or 2, characterized in that: The back plate in step (1) is made of aluminum alloy; Preferably, the threads on the welding surface of the back plate in step (1) are distributed in concentric circles; Preferably, the width of the thread is 1.5-2.5 mm, and the depth of the thread is 1.0-1.5 mm.

4. The welding method according to any one of claims 1 to 3, characterized in that: The cleaning in step (1) is performed using an organic solvent, wherein the organic solvent comprises any one of isopropyl ketone, isopropyl alcohol or ethanol, or a combination of at least two thereof; Preferably, the cleaning method in step (1) includes ultrasonic cleaning; Preferably, the cleaning time in step (1) is 3 to 8 minutes; Preferably, the drying method in step (1) comprises vacuum drying; Preferably, the vacuum drying is carried out at a temperature of 70 to 80° C., a pressure of less than 0.1 Pa, and a time of 0.5 to 1 h.

5. The welding method according to any one of claims 1 to 4, characterized in that: The vacuum packaging method in step (1) is vacuum plastic packaging; Preferably, the vacuum plastic packaging adopts a plastic sealing material including any one of polyethylene, polyethylene terephthalate or polyvinyl chloride or a combination of at least two thereof; Preferably, the vacuum packaging is performed by evacuating the product to a pressure below 500 Pa.

6. The welding method according to any one of claims 1 to 5, characterized in that: In step (2), the target assembly is placed with the aluminum-containing target at the top; Preferably, the shape and size of the compact match the shape and size of the aluminum-containing target; Preferably, the pressing block is made of aluminum alloy.

7. The welding method according to any one of claims 1 to 6, characterized in that: The hydraulic device in step (2) includes an oil press; Preferably, the component on the hydraulic press that is in direct contact with the pressing block is a pressing head, and the pressing head moves up and down.

8. The welding method according to any one of claims 1 to 7, characterized in that: In step (2), the pressure applied by the hydraulic device to the pressing block increases from 20 tons to 90-110 tons, with an increase gradient of 15-25 tons; Preferably, the holding time at each level of pressure is 10 to 60 seconds; Preferably, the holding time when the pressure is less than 60t is 10 to 30s, and the holding time when the pressure is greater than 60t is 30 to 60s; Preferably, the downward pressure amount during the holding time of each level of pressure is measured and recorded.

9. The welding method according to any one of claims 1 to 8, characterized in that: After the pressurization in step (2) is completed, the pressure is directly removed, the vacuum packaging is removed, and the welding of the target assembly is completed; Preferably, the target assembly after welding is inspected to check its bonding properties and whether there are gaps at the welding surface.

10. The welding method according to any one of claims 1 to 9, characterized in that: The welding method comprises the following steps: (1) cleaning and drying an aluminum-containing target and a backing plate with threads on the welding surface, wherein the aluminum-containing target comprises a high-purity aluminum target or an aluminum alloy target, wherein the purity of the high-purity aluminum target is 99.99wt% or more, and the aluminum content of the aluminum alloy target is 95-99.9wt%. The backing plate is made of an aluminum alloy, and the threads on its welding surface are distributed in concentric circles, the width of the threads is 1.5-2.5mm, and the depth of the threads is 1.0-1.5mm. The cleaning is performed with an organic solvent, and the cleaning method comprises ultrasonic cleaning, and the cleaning time is 3-8min. The drying method comprises vacuum drying, and the vacuum drying temperature is 70-80°C, the pressure is below 0.1Pa, and the time is 0.5-1h. Then, the welding surfaces of the two are laminated and vacuum-sealed. The plastic sealing material comprises any one of polyethylene, polyethylene terephthalate, or polyvinyl chloride, or a combination of at least two thereof. During the vacuum packaging, the pressure is evacuated to below 500Pa to obtain an assembled target assembly; (2) placing the target assembly assembled in step (1) on a processing platform of a hydraulic device, wherein the aluminum-containing target is located at the top when the target assembly is placed, and placing a pressure block on the top of the target assembly, wherein the shape and size of the pressure block match the shape and size of the aluminum-containing target, and the material of the pressure block is an aluminum alloy, and the hydraulic device comprises an oil hydraulic press, wherein the component on the oil hydraulic press that is in direct contact with the pressure block is a pressure head, and the pressure head moves up and down, and the pressure gradient of the hydraulic device is set to increase, and the pressure applied by the hydraulic device to the pressure block increases from 20t to 90-110t, and the increase gradient is 15-25t, and the pressure is maintained under each level of pressure, and the pressure maintenance time under each level of pressure is 10-60s, the pressure maintenance time when the pressure is less than 60t is 10-30s, and the pressure maintenance time when the pressure is greater than 60t is 30-60s, and the downward pressure within the pressure maintenance time of each level of pressure is measured and recorded, and the pressure is directly released after the pressurization is completed, and the vacuum packaging is removed to obtain the aluminum-containing target after welding.