TWI677589B - A preparation method of sputtering target - Google Patents

Abstract

The invention relates to a method for preparing and renovating a sputtering target by cold spraying, which is a method in which metal powder is directly deposited on a target back plate by cold spraying. Due to the low working temperature of cold spraying, large-area coatings and thick coatings can be prepared, and subsequent processing can be performed to obtain metal targets of the required size. For the residual target after use, metal powder can also be used to fill the sputtering area of the target surface of the target by cold spraying, making it a reusable target.

Description

Preparation method of sputtering target

The present invention relates to a method for preparing target materials, and more particularly relates to a method for preparing and renovating targets using a cold spraying process.

Sputtering is a physical vapor deposition technique, also known as sputtering deposition / coating. It is a physical process that uses surface atoms in a solid target "target" to be hit by high-energy ions (usually from plasma) to leave the solid target and enter the gas. Sputtering is generally carried out in a vacuum system filled with an inert gas. The high-voltage electric field causes the argon to ionize, generating an argon ion stream to bombard the target on the cathode. Sputtered target material atoms or molecules are deposited on semiconductor wafers or substrates such as glass, ceramics, and metals to form a thin film.

In a high vacuum and high voltage environment, a sputtering target is bombarded with a high-energy argon ion stream, and atoms or molecules on the surface of the target material are released and deposited on a substrate to form a thin film. In order to obtain a good coating effect, the target is usually a high-purity / high-density ceramic compound, metal alloy, or semiconductor compound, and the purity is required to be at least 99%. Traditional new (ie, unused) planar sputtering targets have flat round or flat quasi-rectangular shapes. During the sputtering process, this shape is eroded and is "end of life" by the target, which is the point at which a target is sputtered (end point).

Because the sputtering target material will produce a highly irregular surface morphology at the end of the target life, the irregular surface is characterized by a change in width at different depths, different penetration depths along the surface, and a wide range of angles with the original surface The surface is not conducive to the uniformity of the subsequent sputtering film. Therefore, users of sputtering targets often have to discard the remaining sputtering target material, and therefore discard most of the remaining material of the original target.

In the past, spray deposition has attempted to address the refurbishment of used sputtering targets. The traditional thermal spraying method is a method in which a metal alloy or ceramic powder is sprayed and deposited on the surface of a substrate through a high-heat flame airflow to form a coating. Coatings formed by thermal spraying methods have the following disadvantages: (1) high porosity; (2) high thermal flames can cause metal alloy oxidation or ceramic semiconductor compounds to react with the air to deteriorate; and (3) the thermal expansion coefficient of the coating / substrate The thermal stress caused by the difference will cause the coating to peel and crack growth, so it is impossible to obtain the inherent properties of the sputtering target and the required stacking (filling) thickness. Irregular and / or complex surface thermal sprayed composite powders (that is, a mixture of multiple elements) of the sputtering target after use also often lead to uneven local segregation, which tends to impair the efficacy of the spray refurbishment process.

Therefore, it is necessary to propose a method for target preparation and renovation, which can provide a new target with the same properties (eg, microstructure properties, porosity, composition, and bonding strength) as the original target.

In order to solve the above problems, the main object of the present invention is to provide a method for preparing a sputtering target, which can prepare high The purity / high density metal, metal alloy or semiconductor compound target must have a purity of at least 99%.

In order to solve the above problems, the main object of the present invention is to propose a method for preparing a sputtering target, which can provide the same properties as the original target (for example, microstructural properties, porosity, composition, and bonding strength). New target.

In order to achieve the main purpose of the present invention, the present invention provides a method for preparing a sputtering target, which includes the following steps: providing a back plate, the back plate may be flat, tubular, cylindrical or long; A cold spray deposition gun is disposed on the back plate. The cold spray deposition gun can adjust a distance from the back plate below it and tilt an angle with the back plate. One of the spray rates of the cold spray deposition gun is Determined by the spraying material, and adjusted according to the distance and the angle; spraying spray powder on the backing plate by moving the cold spray deposition gun to deposit on the backing plate to obtain a sputtering target on the backing plate; The particle size of the sprayed powder is between 1.0 μm and 200 μm , preferably between 5.0 μm and 100 μm ; and the sputtering target on the back plate can be obtained by adjusting the distance and the angle. Different shapes of wood.

According to a feature of the invention, the angle is between 45 ° and 135 °.

According to a feature of the present invention, the preparation method further includes: performing a thermal annealing treatment on the sputtering target on the back plate.

According to a feature of the present invention, the thermal annealing treatment is selected from the group consisting of a heat treatment, an infrared treatment, a UV light treatment, a laser treatment, a microwave treatment, and a high frequency treatment.

In order to achieve another object of the present invention, the present invention provides a new method for preparing a sputtering target. The sputtering target has a recessed surface erosion area, and the recessed surface erosion area is non-planar. The preparation method includes the following steps. : Setting a cold spray deposition gun on the surface erosion area of the depression; adjusting a distance between the cold spray deposition gun and the surface erosion area of the depression below and tilting an angle with the surface erosion area of the depression The spray rate of one of the cold spray deposition guns is determined by the spraying material, and is adjusted according to the distance and the angle; by moving the cold spray deposition gun, spray coating on the recessed surface erosion area of the sputtering target Powder coating, deposited on the recessed surface erosion area to form a whole new sputtering target; wherein the particle size of the spray powder is between 1.0 μm to 200 μm , preferably 5.0 μm to 100 μ m.

According to a feature of the invention, the angle is between 45 ° and 135 °.

According to a feature of the present invention, the preparation method further includes: performing a surface processing on the new sputtering target.

Different from the subtractive processes such as melting, casting, forging, and machining of traditional metal targets, the method for preparing the sputtering target of the present invention uses a cold spray method. Cold spraying is a technology that does not melt or vaporize the powder material, but causes it to accompany the inactive gas, maintain the original solid state at a supersonic flow, and cause it to impact the sprayed object to form a film. The powder material under supersonic impact, particles exceeding the critical speed, so that the matrix solid phase powder material leaves together with the inert gas in the ultrasonic flow without gasification, and the powder material body will plastically deform to form a film, so its The porosity is extremely low. Due to the low working temperature of cold spraying, large-area coatings and thick coatings can be prepared, and there is no uneven segregation of molten components and problems of atmospheric high-temperature reaction deterioration, which can avoid coatings. The thermal stress caused by the difference in the thermal expansion coefficient of the substrate significantly reduces the risk of coating peeling and crack growth, and can be subsequently processed locally to obtain a metal target of the required size. For the residual target after use, metal powder can also be used to fill the erosion area of the target surface of the residual target by cold spraying, making it a reusable target.

In the method of the present invention, the deposit obtained by the cold spraying method can have extremely low porosity and high density, and high-purity / high-density metal, metal alloy, or semiconductor compound target materials can be prepared on various shapes of base plates. The purity requirements thereof At least 99% or more, it can also provide a new target with the same properties (eg, microstructure properties, porosity, composition, and bonding strength) as the original target.

100‧‧‧cold spray system

110‧‧‧painted objects

120‧‧‧ Cold Jet Deposition Gun

122‧‧‧distance

124‧‧‧ angle

130‧‧‧ spray powder

140‧‧‧ powder storage tank

150‧‧‧air storage tank

200‧‧‧ prepared sputtering target

210‧‧‧ back plate

222‧‧‧ Depression surface erosion area

224‧‧‧ Filling layer

300‧‧‧ New sputter target

In order to make the above and other objects, features, and advantages of the present invention more comprehensible, several preferred embodiments are exemplified below, and described in detail with the accompanying drawings.

FIG. 1 is a schematic diagram showing an embodiment of a method for preparing a sputtering target according to the present invention.

FIG. 2 is a schematic diagram showing a new method for preparing a sputtering target according to the present invention.

FIG. 3 is a flowchart of a first embodiment of a method for preparing a sputtering target according to the present invention.

FIG. 4 is a schematic diagram showing the implementation of a newly prepared sputtering target according to the present invention.

FIG. 5 is a flowchart of a second embodiment of a method for preparing a sputtering target according to the present invention.

Although the present invention may be embodied in different forms of embodiments, those shown in the accompanying drawings and described herein are preferred embodiments of the present invention. Those skilled in the art will understand that the device and method specifically described herein and illustrated in the accompanying drawings are considered as an example of the present invention. Restrictive illustrative embodiments, and the scope of the present invention is defined only by the scope of patent applications. Features illustrated or described in connection with one exemplary embodiment can be combined with features of other embodiments. Such modifications and variations are included in the scope of the present invention.

Please refer to FIG. 1, which illustrates a schematic diagram of an embodiment of a method for preparing a sputtering target according to the present invention. This figure is a simplified representation of the cold spraying system 100 for the route of the process gas, heating, and powder supply. N ₂ gas, He gas, and other inert gases provided from the gas supply tank (Gas Cylinder) 150 of the cold spray system 100 are supplied from the primary gas to a predetermined pressure as a process gas through a pressure regulator (not shown). . The pressure of high-pressure process gas can also reach 1 ~ 10MPa.

In addition, when the gas passes through the heater of the cold spraying system 100, it is heated to a predetermined temperature, and reaches 300 ° C or more. When the high-temperature and high-pressure gas passes through the outlet of the cold spray deposition gun 120 of the cold spray system 100, the gas flow rate reaches a spray rate, and even reaches a supersonic speed as the process gas.

The spray powders 130 for depositing target materials are transported from a powder storage tank 140 of the cold spray system 100 into the cold spray deposition gun 120 to supply the high-temperature and high-pressure gas. Because the high-temperature and high-pressure process gas can reach 300 ° C or higher at the outlet of the cold spray deposition gun 120, the process gas pressure can also reach 1 MPa to 10 MPa. The spray powders 130 are accelerated by the high-temperature and high-pressure process gas. At the exit of the spray deposition gun 120, after reaching the highest speed, it impacts on the surface of a spraying object 110 to form a film. The spraying rate of the spraying powders 130 is accelerated to reach a speed of 200 m / s to 1200 m / s, so that it impacts on the surface of the spraying object 110 to form a film.

Since the accelerated temperature of the particles of the spraying powder 130 before impacting the spraying object 110 is lower than the melting point of the spraying powder 130, the formed film is hardly oxidized. Different from the traditional spraying methods, After the flame or plasma is melted and sprayed on the substrate, the cold sprayed material will not be affected by heat and will not change its characteristics, so the oxidation of the film produced by cold spraying can be controlled to a minimum.

The shape of the sprayed object 110 is not limited, and may be a flat type, a tube type, a cylindrical type, or a long type. If the sprayed object 110 is a tube or a cylinder, the sprayed object 110 can be rotated around the axis 115 while the sprayed object 110 is rotated around the axis 115, and the cold spray deposition gun 120 is sprayed on the tube. Move in the direction of 110 axis to spray.

Please refer to FIG. 2, which shows a schematic diagram of a new method for preparing a sputtering target according to the present invention. Please refer to FIG. 3, which shows a flowchart of a first embodiment of a method for preparing a sputtering target according to the present invention. A method for preparing a sputtering target includes the following steps: Step 1: Provide a back plate 210, the back plate 210 may be planar, tubular, cylindrical, or long; step 2: deposit a cold spray The gun 120 is disposed on the back plate 210. The cold spray deposition gun 120 can adjust a distance 122 from the back plate below it and tilt an angle 124 with the back plate. The spray of the cold spray deposition gun 120 The speed is determined by the spraying material, and is adjusted according to the distance and angle; Step 3: Spray the spraying powder on the backing plate 210 by moving the cold spray deposition gun 120 to deposit on the backing plate 210 to obtain the backing A sputtering target 220 is provided on the plate 210; wherein the particle size of the spray powders 130 is between 1.0 μm and 200 μm, and preferably between 5.0 μm and 100 μm. And different shapes of the sputtering target 220 on the back plate 210 can be obtained by adjusting the distance 122 and the angle 124.

The embodiment of the present invention is a dense and thick deposit obtained by controlling the particle diameter of the spray powders 130 and cold spraying. One technical feature of the present invention is to control the particle size distribution of the spray powders 130 used in order to obtain dense and thick deposits in the cold spray method (coating). The particle diameter of the spray powders 130 is between 1.0 μm and 200 μm; preferably, the particle diameters of the spray powders 130 have a cumulative particle size distribution such that the 10% particle diameter (D10) is 1.0 μm to 20.0 μm , The 50% particle diameter is 30.0 μm to 70.0 μm , and the 90% particle diameter is 70.0 μm to 125.0 μm .

The distance 122 is between 10mm and 100mm; preferably, the distance 122 is between 10mm and 50mm. The angle 124 is between 45 ° and 135 °; preferably, the angle 124 is between 50 ° and 130 °. The spray flying speed of the spray powders 130 sprayed out by the cold spray deposition gun 120 is between 300 m / s and 1000 m / s.

Since the spray powders 130 are kept in a solid state and plastically deformed to form a film, there are no problems such as chemical changes and tissue changes. In addition, the spray powders 130 are formed by a high-speed impact method, and the formed film is very dense, and usually has a porosity of 1% or less. The thickness 222 of the sputtering target 220 can reach a thickness of more than 20um, preferably between 10mm and 50mm. The adhesion rate of almost all kinds of metal materials is above 90%, and the film-forming speed can be greater than 1 kg per hour. Because high-pressure gas higher than the general spraying method and lower temperature than the melting point are used for spraying, it is also suitable for target materials that are difficult to form a film, such as alloy metals such as nickel (Ni), titanium (Ti), and stainless steel. The film is formed with a high adhesion rate, and does not cause problems such as uneven segregation of molten components and high-temperature reaction deterioration.

The sputtering target 200 prepared by the present invention includes a back plate 210 and the sputtering target 220. The shape of the prepared sputtering target 200 is not limited, and may be a planar target, a tube target, or a long target. . Therefore, the back plate 210 may be a flat type, a tube type, a cylindrical type, or a long type. The shape of the sputtering target 220 according to the present invention may be a planar target, a tube target, or a long target, and the like, and may be adjusted by changing the distance 122 and the angle 124. In one embodiment, the sputtering target 220 is a tube type. Therefore, the deposited sputtering target 220 is located on the outer peripheral surface of a tube-shaped base plate, and the cold spray molding can be carried around by one side of the tube-shaped base plate. Its axis is rotated, while the cold spray deposition gun is moved in the axial direction of the sputtering target of the tubular base plate to achieve it.

The embodiment of the present invention includes: preparing a powder of the same purity component as the sputtering target, using the powder as a raw material, and forming the sputtering target by cold spraying on the back plate. The materials of the spray powders 130 are, for example, but not limited to, aluminum and aluminum alloys, copper and copper alloys, titanium and titanium alloys, molybdenum and molybdenum alloys, chromium, iron, stainless steel, aging steel, nickel-based alloys, and cobalt-based Alloys, etc.

In the manufacturing method, after step 2, the method further includes a step of performing a surface pretreatment on the back plate 210. The pretreatment uses a high-temperature and high-pressure process gas to directly bombard the surface of the back plate 210 to improve the adhesion of the subsequent spray powders 130 on the surface of the back plate 210.

The preparation method further includes a step of performing a surface processing on the sputtering target 220 on the back plate 210. The surface processing includes, but is not limited to, (1) hot dip plating: The prepared sputtering target 200 includes a process in which a back plate 210 and the sputtering target 220 are placed in a molten metal to form a coating on the surface. (2) Thermal spraying: The prepared sputtering target 200 is a process in which a sprayed molten metal is sprayed on the surface of a workpiece to form a coating. (3) Hot stamping: a process in which a metal foil is heated and pressurized to cover the surface of the prepared sputtering target 200 to form a coating layer. (4) Chemical heat treatment: a process in which the prepared sputtering target 200 is brought into contact with a chemical substance, heated, and a certain element enters the surface of the workpiece under a high temperature state, such as nitriding or carburizing. (5) Surfacing: The process of depositing the cladding metal on the surface of the prepared sputtering target 200 by welding to form a welding layer is called surfacing, such as surfacing welding of wear-resistant alloys. (6) Electroplating: a method of laying a layer of metal on the back plate 210 by using the principle of electrolysis to form the prepared sputtering target 200.

The preparation method further includes a step of performing a thermal annealing treatment on the newly-reformed sputtering target 300. The thermal annealing treatment is selected from the group consisting of: heat treatment, infrared treatment, UV light treatment, laser treatment, microwave treatment, and high frequency treatment.

Please refer to FIG. 4, which is a schematic diagram showing the implementation of a newly prepared sputtering target according to the present invention. Please refer to FIG. 5, which shows a second embodiment of a method for preparing a sputtering target according to the present invention. flow chart. A method for preparing a sputtering target. The sputtering target 210 has a recessed surface erosion region 222. The recessed surface erosion region 222 is non-planar. The preparation method includes the following steps: Step 1: a cold spray deposition gun 120 It is arranged on the surface erosion area 222 of the depression; Step 2: Adjust the distance 120 between the cold spray deposition gun 120 and the surface erosion area 222 of the depression below it and incline the surface erosion area 222 of the depression by one Angle 124, the spray rate of the cold spray deposition gun 120 is determined by the spraying material, and adjusted according to the distance and the angle; step 3: by moving the cold spray deposition gun 120 in the depression of the sputtering target 210 The sprayed powder 130 is sprayed on the surface erosion area 222 and is deposited on the recessed surface erosion area 222 to form a new sputtering target 300. The particle size of the spray powder 130 is between 1.0 μm and 200 μm.

Prior to step 1, the recessed surface erosion region 222 further includes a cleaning step to remove surface dirt. The embodiment of the present invention is a dense and thick deposit obtained by controlling the particle diameter of the spray powders 130 and cold spraying. One technical feature of the present invention is to control the particle size distribution of the spray powders 130 used in order to obtain dense and thick deposits in the cold spray method (coating). The particle diameter of the spray powders 130 is between 1.0 μm and 200 μm; preferably, the particle diameters of the spray powders 130 have a cumulative particle size distribution such that the 10% particle diameter (D10) is 1.0 μm to 20.0 μm , The 50% particle diameter is 30.0 μm to 70.0 μm , and the 90% particle diameter is 70.0 μm to 125.0 μm .

The distance 122 is between 10mm and 100mm; preferably, the distance 122 is between 10mm and 50mm. The angle 124 is between 45 ° and 135 °; preferably, the angle 124 is between 50 ° and 130 °. When the distance 122 becomes larger or the angle 124 becomes smaller, the flying speed of the spray powder of the cold spray deposition gun 120 is between 300 m / s and 1000 m / s.

Because these spray powders 130 are kept in a solid state and plastically deformed It forms a film, so it does not cause problems such as chemical changes and tissue changes. In addition, the spray powders 130 are formed by a high-speed impact method, and the formed film is very dense, and usually has a porosity of 1% or less. The thickness 222 of the sputtering target 220 can reach a thickness of more than 10 mm, preferably between 10 mm and 50 mm. The adhesion rate of almost all kinds of metal materials is above 90%, and the film formation speed can reach 30 kg per hour. Because high-pressure gas higher than the general spraying method and lower temperature than the melting point are used for spraying, it is also suitable for target materials that are difficult to form a film, such as alloy metals such as nickel (Ni), titanium (Ti), and stainless steel. The film is formed with a high adhesion rate, and does not cause problems such as uneven segregation of molten components and high-temperature reaction deterioration.

The sputtering target 300 prepared by the present invention includes a back plate 210 and the sputtering target 220. The shape of the prepared sputtering target 300 is not limited, and can be a planar target, a tube target, or a long target. . Therefore, the back plate 210 may be a flat type, a tube type, a cylindrical type, or a long type. The shape of the sputtering target 220 according to the present invention may be a planar target, a tube target, or a long target, etc., which can be adjusted by changing the distance 122 and the angle 124.

In one embodiment, the sputtering target 220 having a recessed surface erosion region 222 is a tube type. Therefore, the sputtering target 220 having a recessed surface erosion region 222 is located on the outer peripheral surface. The cold spray forming of the filling layer 224 can be performed by one side. The sputtering target 220 of the tube type is rotated around its axis, and the cold spray deposition gun 120 is moved and sprayed in the axial direction of the sputtering target 220 of the tube type.

The filling layer 224 is formed by cold spraying on the sputtering surface of the sputtering target 220 with the recessed surface erosion region 222 to constitute the regenerated sputtering target. The interface between the filling layer 224 and the recessed surface erosion area 222 is a material discontinuity. The material discontinuity refers to the difference in microstructure characteristics, which may be a crystalline structure phase. Composition, grain size or porosity, or a combination of the above.

The embodiment of the present invention includes: a surface intrusion having a depression after preparation and use A powder of the same purity component of the sputtering target 220 in the etched region 222 is used as a raw material, and the sputtering target 220 has a recessed surface erosion region 224 after use by cold spraying to form The filling layer 224 is formed by spraying the spray powder 130. The materials of the spray powders 130 are, for example, but not limited to, aluminum and aluminum alloys, copper and copper alloys, titanium and titanium alloys, molybdenum and molybdenum alloys, chromium, iron, stainless steel, aging steel, nickel-based alloys, and cobalt-based Alloys, etc.

In the preparation method, after step 2, the method further includes the step of performing a surface pretreatment on the surface erosion region 222 of the sputtering target 220 having a recess. Wherein, the pretreatment uses a high-temperature and high-pressure process gas to directly bombard the surface of the sputtering target 220 with the recessed surface erosion region 222 to improve the subsequent sprayed powder 130 on the sputtering target 220 with the recessed surface. Adhesion on the surface of the erosion area 222.

The preparation method further includes a step of performing a surface processing on the refurbished sputtering target 300. Surface processing includes, but is not limited to, (1) hot dip plating: a process in which a new sputtering target 300 is put into a molten metal to form a coating on its surface. (2) Thermal spraying: The process of forming a new sputtering target 300 by atomizing it with molten metal and spraying it on the surface of the workpiece to form a coating. (3) Hot stamping: a process in which metal foil is heated and pressurized to cover the surface of the new sputtering target 300 to form a coating layer. (4) Chemical heat treatment: a process in which the sputtering target 300 is brought into contact with a chemical substance, heated, and a certain element is allowed to enter the surface of the workpiece under a high temperature state, such as nitriding or carburizing. (5) Surfacing: The process of depositing the cladding metal on the surface of the new sputtering target 300 by welding to form a welding layer is called surfacing, such as surfacing welding of wear-resistant alloys. (6) Electroplating: A method of laying a layer of metal on the reformed sputtering target 300 by using the principle of electrolysis to form the reformed sputtering target 300.

The preparation method further includes a step of performing a thermal annealing treatment on the newly-reformed sputtering target 300. The thermal annealing treatment is selected from the group consisting of heat treatment, infrared treatment, UV light treatment, laser treatment, and microwave treatment.

Although the present invention has been disclosed in the foregoing preferred embodiments, it is not intended to limit the present invention. Invention, anyone skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. As explained above, all types of modifications and changes can be made without destroying the spirit of the invention. Therefore, the protection scope of the present invention shall be determined by the scope of the appended patent application.

Claims (10)

A method for preparing a sputtering target includes the following steps: providing a back plate, the back plate may be a flat type, a tube type, a cylindrical type or a long type; setting a cold spray deposition gun on the back plate, The cold spray deposition gun can adjust a distance from the back plate below it and tilt an angle with the back plate; by moving the cold spray deposition gun on the back plate, a high-temperature and high-pressure process gas spray coating is performed. The powder is deposited on the back plate to obtain a sputtering target. One spray rate of the cold spray deposition gun is determined by the spray material. The spray speed is between 200m / s and 1200m / s. The process gas The pressure is between 1 MPa and 10 MPa; the particle size of the sprayed powder is between 1.0 μm and 200 μm ; different shapes of the sputtering target on the back plate can be obtained by adjusting the distance and the angle. The preparation method according to claim 1, wherein the angle is between 45 ° and 135 °. The preparation method according to claim 1, wherein the distance is between 10 mm and 100 mm. The preparation method according to claim 1, further comprising: performing a surface processing on the sputtering target on the back plate. The manufacturing method according to claim 1, further comprising: performing a thermal annealing treatment on the sputtering target on the back plate. The preparation method according to claim 5, wherein the thermal annealing treatment is selected from the group consisting of a heat treatment, an infrared treatment, a UV light treatment, a laser treatment, a microwave treatment, and a high frequency treatment. A method for preparing a sputtering target. The sputtering target has a recessed surface erosion area. The recessed surface erosion area is non-planar. The preparation method includes the following steps: a cold spray deposition gun is set on the recessed surface erosion. Area; adjust the distance between the cold spray deposition gun and the surface erosion area of the depression below it and tilt at an angle with the surface erosion area of the depression, and one of the spray speeds of the cold spray deposition gun is determined by the distance And the angle is determined; by moving the cold spray deposition gun on the surface erosion area of the depression of the sputtering target, spray powder with a process gas at a high temperature and high pressure, and deposit on the surface erosion area of the depression to form a Renovate the sputtering target; the particle size of the spray powder is between 1.0 μm and 200 μm , the spray speed is between 200m / s and 1200m / s, and the process gas pressure is between 1MPa and 10MPa. The method according to claim 7, wherein the angle is between 45 ° and 135 °. The preparation method according to claim 7, wherein the distance is between 10 mm and 100 mm. The preparation method according to claim 7, further comprising: performing a surface processing on the fresh sputtering target on the back plate to planarize the surface of the sputtering target.