Magnetron sputtering target material assembly and thin film deposition equipment

Abstract

The invention discloses a magnetron sputtering target material assembly and thin film deposition equipment. The planar target is a large-area planar target, the back plate is connected to the target connecting face of the planar target, the cover plate is connected to the side, away from the planar target, of the back plate, and the cover plate and the back plate jointly define at least two cooling channels. On one hand, cooling liquid can flow between the back plate and the cover plate due to the arrangement of the cooling channels so as to quickly adjust the temperatures of the plane target, the back plate and the cover plate, on the other hand, at least two cooling channels are arranged between the back plate and the cover plate, and the cooling efficiency of the plane target can be effectively improved due to the arrangement of the multiple cooling channels for the large-area plane target. According to the magnetron sputtering target material assembly, the cooling efficiency of cooling liquid on the plane target can be improved.

Description

Technical Field

[0001] This invention relates to the field of vacuum thin film deposition technology, and in particular to a magnetron sputtering target assembly and thin film deposition equipment. Background Technology

[0002] In magnetron sputtering, the target temperature varies with the sputtering power, making target cooling crucial for quality control. Current technologies often employ a water tank above the target, containing circulating cooling water, with the magnetron immersed in the water. The magnetron can translate and rotate within the tank, and the magnetron agitates the water to improve cooling efficiency. However, for large-area planar targets, this method suffers from low cooling efficiency and poor effectiveness. High water pressure can also cause severe deformation of the planar target, making it unsuitable for the demands of magnetron sputtering of large planar targets. Summary of the Invention

[0003] The main objective of this invention is to provide a magnetron sputtering target assembly and thin film deposition equipment that can solve the technical problem of low target cooling efficiency.

[0004] To achieve the above objectives, this application proposes a magnetron sputtering target assembly, which includes a planar target, a backplate, and a cover plate. The planar target has a sputtering surface and a target connection surface arranged opposite each other along a first direction. The projection surface is perpendicular to the first direction, and the projected area S of the sputtering surface along the first direction on the projection surface satisfies: S ≥ 0.2 m². 2 The backplate is connected to the target connection surface of the planar target. The cover plate is connected to the side of the backplate away from the planar target. The cover plate and the backplate together define at least two cooling channels for the flow of coolant, which is used to cool the planar target.

[0005] In some embodiments, the back plate and the cover plate together define a coolant inlet and a coolant outlet that are respectively provided for each cooling channel. One end of the cooling channel is connected to the coolant inlet and the other end is connected to the coolant outlet. The cooling channel bends and extends from the coolant inlet to the coolant outlet.

[0006] In some embodiments, the cover is configured as a bent plate adapted to the cooling channel, and the cover is connected to the back plate along the extension path of the cooling channel.

[0007] In some embodiments, along a first direction, the projection of the back plate onto the projection surface has a first shape, and the projection of the cover plate onto the projection surface has a second shape, the first shape being similar to the second shape, and the edge of the cover plate being connected to the back plate.

[0008] In some embodiments, the back plate has a back plate connecting surface, the cover plate has a cover plate connecting surface, and the cover plate connecting surface and the back plate connecting surface together define a cooling channel; wherein, the cooling channel is recessed on the side of the back plate connecting surface away from the cover plate connecting surface; and / or, the cooling channel is recessed on the side of the cover plate connecting surface away from the back plate connecting surface.

[0009] In some embodiments, the back plate and the cover plate together define a coolant inlet and a coolant outlet that are respectively provided for each cooling channel. One end of the cooling channel is connected to the coolant inlet and the other end is connected to the coolant outlet. The magnetron sputtering target assembly also includes a flow divider block disposed in the cooling channel so that the cooling channel forms at least two branches.

[0010] In some embodiments, the backplate is welded to the target connection surface.

[0011] In some embodiments, the backplate is integrally formed with the planar target.

[0012] In some embodiments, the cover plate is welded to the back plate.

[0013] In some embodiments, the magnetron sputtering target assembly further includes a connecting bolt, one end of which is connected to the cover plate and the other end of which is connected to the back plate.

[0014] In some embodiments, the magnetron sputtering target assembly further includes a sealing component for limiting coolant leakage from the cooling channel to the back and sides of the magnetron sputtering target assembly.

[0015] In some embodiments, the sealing component includes a cooling channel sidewall sealing ring, a cover plate and a back plate together defining a cooling channel sidewall sealing groove, the cooling channel sidewall sealing groove communicating with the cooling channel, and the cooling channel sidewall sealing ring disposed in the cooling channel sidewall sealing groove.

[0016] In some embodiments, the sealing component includes a peripheral sealing ring, a cover plate and a back plate together defining a peripheral sealing groove, the peripheral sealing groove being disposed along the edge of the contact surface between the cover plate and the back plate, and the peripheral sealing groove being spaced from the cooling channel, and the peripheral sealing ring being disposed in the peripheral sealing groove.

[0017] In some embodiments, the magnetron sputtering target assembly further includes a connecting bolt, one end of which is connected to a cover plate and the other end of which is connected to a back plate. The sealing component includes a connecting bolt sealing ring. The cover plate and the back plate together define a connecting bolt sealing groove, which surrounds the connecting bolt. The connecting bolt sealing ring is disposed in the connecting bolt sealing groove.

[0018] A second aspect of this application also discloses a thin film deposition apparatus, which includes a magnetron sputtering target assembly according to any of the above embodiments.

[0019] Compared with the prior art, the beneficial effects of the present invention are:

[0020] In this invention, the planar target is a large-area planar target. A back plate is connected to the target connection surface of the planar target, and a cover plate is connected to the side of the back plate away from the planar target. The cover plate and the back plate together define at least two cooling channels. On one hand, the cooling channels allow coolant to flow between the back plate and the cover plate, thereby quickly regulating the temperature of the planar target, the back plate, and the cover plate. On the other hand, the presence of at least two cooling channels between the back plate and the cover plate effectively improves the cooling efficiency of the planar target for a large-area planar target. This invention improves the cooling efficiency of the coolant on the planar target. Furthermore, the cooling of the planar target in this invention is achieved by the coolant flowing through the cooling channels between the back plate and the cover plate, eliminating the need for a cooling water tank as in previous technologies and significantly reducing the deformation of the planar target caused by the high pressure of the coolant. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of the assembly structure of the back plate and the planar target in one embodiment of the present invention;

[0023] Figure 2 For the present invention Figure 1 A schematic cross-sectional view of section AA in the embodiment;

[0024] Figure 3 This is a first-view exploded structural diagram of the magnetron sputtering target assembly in the first embodiment of the present invention, wherein the cover plate and the back plate are configured as bent plates, and the cover plate is connected to the back plate by an inlay method, and the back plate is connected to the planar target by welding, indium bonding or integral molding.

[0025] Figure 4 This is a second-view exploded structural diagram of the magnetron sputtering target assembly in the first embodiment of the present invention;

[0026] Figure 5 This is a top view of the cover plate side of the magnetron sputtering target assembly in the first embodiment of the present invention;

[0027] Figure 6 This is the first embodiment of the present invention. Figure 5 Schematic diagram of the cross-sectional structure at point BB;

[0028] Figure 7 This is the first embodiment of the present invention. Figure 6 A magnified view of a portion of the cooling channel at point H;

[0029] Figure 8 The cooling channel in this embodiment of the invention is different from... Figure 7 A structure;

[0030] Figure 9 This is an exploded structural diagram of the magnetron sputtering target assembly in the second embodiment of the present invention, wherein the cover plate is configured as a flat plate and the cover plate is not configured with bends corresponding to the cooling channels.

[0031] Figure 10 This is a schematic diagram of the assembly of the magnetron sputtering target assembly in the second embodiment of the present invention, wherein the bent and shaded part is the cooling channel path;

[0032] Figure 11 This is the second embodiment of the present invention. Figure 10 A schematic diagram of the cross-sectional structure at the CC section;

[0033] Figure 12 This is the second embodiment of the present invention. Figure 11 A magnified view of a portion of point I in the middle;

[0034] Figure 13 This is an exploded structural diagram of the magnetron sputtering target assembly in the third embodiment of the present invention, wherein the magnetron sputtering target assembly is provided with a cooling channel sidewall sealing ring;

[0035] Figure 14 This is a top view of the cover plate side of the magnetron sputtering target assembly in the third embodiment of the present invention, wherein the magnetron sputtering target assembly has connecting bolts arranged in a dot matrix.

[0036] Figure 15 This is the third embodiment of the present invention. Figure 14 Schematic diagram of the cross-sectional structure at point DD;

[0037] Figure 16 This is the third embodiment of the present invention. Figure 15 A partially enlarged schematic diagram at point J, showing that the magnetron sputtering target assembly is equipped with a cooling channel sidewall sealing ring;

[0038] Figure 17 This is a schematic diagram of the cover plate structure of the magnetron sputtering target assembly in the third embodiment of the present invention. The cover plate is provided with a cooling channel and sealing components corresponding to the connecting bolts, including a cooling channel sidewall sealing groove and a cooling channel sidewall sealing ring.

[0039] Figure 18This is an exploded structural diagram of the magnetron sputtering target assembly in the fourth embodiment of the present invention, wherein the magnetron sputtering target assembly is provided with an outer sealing ring and a connecting bolt sealing ring;

[0040] Figure 19 This is a top view of the outer side of the cover plate of the magnetron sputtering target assembly in the fourth embodiment of the present invention;

[0041] Figure 20 This is the fourth embodiment of the present invention. Figure 19 Schematic diagram of the cross-sectional structure at the middle EE;

[0042] Figure 21 This is the fourth embodiment of the present invention. Figure 20 A magnified view of a portion of point H in the middle;

[0043] Figure 22 This is the fourth embodiment of the present invention. Figure 19 Schematic diagram of the cross-sectional structure at the middle FF point;

[0044] Figure 23 This is the fourth embodiment of the present invention. Figure 19 A schematic diagram of the cross-sectional structure at point GG.

[0045] Figure 24 This is a schematic diagram of the structure of a thin film deposition apparatus according to an embodiment of the present invention;

[0046] Explanation of icon numbers:

[0047] 30 - Magnetron sputtering target assembly;

[0048] 32-Planar target;

[0049] 34-Sputtering surface;

[0050] 36-Target connection surface;

[0051] 38 - Backplate;

[0052] 40 - Cover plate;

[0053] 42 - Cooling channel;

[0054] 44 - Coolant inlet;

[0055] 46 - Coolant drain port;

[0056] 48 - Backplate connection surface;

[0057] 50 - Cover plate connection surface;

[0058] 52-Shunting Block;

[0059] 53-tributaries;

[0060] 54 - Sealing components;

[0061] 56 - Connecting bolts;

[0062] 58 - Cooling channel sidewall seal ring;

[0063] 60 - Cooling channel sidewall sealing groove;

[0064] 62 - Outer sealing ring;

[0065] 64 - External sealing ring;

[0066] 66 - Connecting bolt sealing ring;

[0067] 68 - Connecting bolt sealing groove;

[0068] 69 - Sealing surface;

[0069] 70 - Thin film deposition equipment;

[0070] 72 - Thin film deposition cavity;

[0071] 74-Substrate stage;

[0072] 76-substrate;

[0073] 78 - Main power supply;

[0074] 80-Flow meter;

[0075] 82 - Vacuum pump;

[0076] 84-magnetron;

[0077] 86-Upper chamber;

[0078] 88-Insulating block;

[0079] 90-Upper masking plate;

[0080] 92-Lower mask;

[0081] 94-Substrate plate;

[0082] 96-Collimator;

[0083] 98-DC bias;

[0084] 100 - Electromagnetic coil;

[0085] 102-RF power supply;

[0086] 104-Matcher;

[0087] First direction Z.

[0088] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0089] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0090] In magnetron sputtering, the target temperature varies with the sputtering power, making target cooling crucial for quality control. Current technologies often employ a water tank above the target, containing circulating cooling water, with the magnetron immersed in the water. The magnetron can move and rotate within the tank, agitating the water to improve cooling efficiency. However, for large-area targets, this method suffers from low cooling efficiency and poor effectiveness, failing to meet the requirements of magnetron sputtering for large planar targets.

[0091] To solve the above technical problems, such as Figures 1 to 23 The present invention proposes a magnetron sputtering target assembly, which includes a planar target, a back plate and a cover plate.

[0092] like Figure 1 as well as Figure 2 As shown, the planar target 32 ​​of the magnetron sputtering target assembly 30 has a sputtering surface 34 and a target connecting surface 36 arranged opposite each other along the first direction Z. The projection surface is perpendicular to the first direction Z, and the projected area S of the sputtering surface 34 along the first direction Z on the projection surface satisfies: S≥0.2m 2 The planar target 32 ​​can be configured as a disc-shaped plate, a square plate, or any other suitable shape. In the magnetron sputtering target assembly 30 of the present invention, the planar target 32 ​​is a large-area plate; specifically, a large-area planar target 32 ​​means that the projected area S of the sputtering surface 34 is not less than 0.2 m². 2 The target material, taking a disc-shaped planar target 32 ​​as an example, refers to a planar target 32 ​​with a diameter of not less than 500 mm. The shapes of the sputtering surface 34 and the target connection surface 36 can be the same or different, and there is no restriction here.

[0093] like Figure 2 As shown, the backplate 38 is connected to the target connection surface 36 of the planar target 32. Specifically, the backplate 38 can be connected to the planar target 32 ​​by welding, indium bonding, or integral molding.

[0094] like Figures 3 to 8As shown, in the first embodiment of the present invention, a cover plate 40 is connected to the side of the back plate 38 opposite to the planar target 32. The cover plate 40 and the back plate 38 together define at least two cooling channels 42, which are used for the flow of coolant so that the coolant can cool the planar target 32. It is understood that the heat on the planar target 32 ​​can be transferred from the planar target 32 ​​to the back plate 38, and the coolant between the back plate 38 and the cover plate 40 can cool the back plate 38, thereby achieving the cooling of the planar target 32. Specifically, to cool the planar target 32, the coolant, after absorbing heat from the target 32, needs to be discharged or cooled and then returned to the cooling channel 42. Therefore, the cooling channel 42 can be equipped with a coolant inlet 44 and a coolant outlet 46 connected to the coolant supply system. At least two cooling channels 42 are provided between the back plate 38 and the cover plate 40, each with its own coolant inlet 44 and coolant outlet 46. In other words, the cooling channels 42 are not interconnected within the back plate 38 and the cover plate 40. Furthermore, the coolant can cool the planar target 32. Preferably, along the first direction Z, the projection of the cooling channel 42 on the projection surface can cover the projection of the sputtering surface 34 on the projection surface. It should be noted that the projection of the cooling channel 42 onto the projection surface covering the projection of the sputtering surface 34 means that the overall outline of the projections of the multiple cooling channels 42 covers the projection of the sputtering surface 34. There may be gaps between the cooling channels 42, and the cooling channels 42 themselves may be bent and spaced apart. There are no restrictions here.

[0095] In this invention, the planar target 32 ​​is a large-area planar target 32. A back plate 38 is connected to the target connection surface 36 of the planar target 32, and a cover plate 40 is connected to the side of the back plate 38 facing away from the planar target 32. The back plate 38 and the cover plate 40 together define at least two cooling channels 42. On one hand, the cooling channels 42 allow coolant to flow between the back plate 38 and the cover plate 40, thereby quickly regulating the temperature of the planar target 32, the back plate 38, and the cover plate 40. On the other hand, the presence of at least two cooling channels 42 between the back plate 38 and the cover plate 40 effectively improves the cooling efficiency of the large-area planar target 32. Figure 5As shown, taking the magnetron sputtering target assembly 30 with two cooling channels 42 as an example, the meandering cooling channels 42 are designed to uniformly cover all areas of the large-area sputtering surface 34, ensuring uniform cooling of the planar target 32. Circulating water or other circulating coolants can flow through the cooling channels 42. The magnetron sputtering target assembly 30 has two cooling channels 42, correspondingly two coolant inlets 44 and two coolant outlets 46. The arrangement of two cooling channels 42 effectively avoids the cooling channels 42 corresponding to the large-area planar target 32 ​​becoming too long. For a large-area planar target 32, if the cooling channels 42 are one inlet and one outlet, the length of the cooling channels 42 would be relatively long. As the cooling channels 42 lengthen and narrow, the fluid pressure drops significantly during coolant flow, affecting the coolant flow rate and limiting heat dissipation capacity, ultimately causing the target surface temperature to rise excessively. In order to control the coolant pressure and flow rate within a suitable range, the larger the area of ​​the planar target 32, the more coolant inlets and outlets there are. In the cooling of a large-area planar target 32, multiple inlets and outlets of coolant are necessary.

[0096] It should be noted that in magnetron sputtering, the cavity containing the planar target is generally under vacuum. In existing technologies, the target is cooled by a water tank, resulting in a vacuum on one side and high water pressure on the other. If the water pressure in the tank is too high, the pressure difference between the two sides of the target will be too large, causing the planar target to easily deform, thus affecting the film formation process of magnetron sputtering. If the water pressure in the tank is too low, the cooling effect of the target will be poor, which will also affect the film quality of magnetron sputtering. Especially for large-area planar targets, excessive water pressure makes the target more prone to deformation. In this invention, the cooling channel 42 replaces the cooling water tank. The area of ​​the cooling channel is much smaller than the area of ​​the entire target backplate corresponding to the cooling water tank, and the cooling channel is relatively narrow. The cooling channel 42 effectively reduces the deformation of the planar target 32 ​​caused by water pressure. Furthermore, the cooling channel 42 eliminates the need for a water tank on the back side of the magnetron sputtering target assembly 30, allowing for a vacuum in the back cavity (sometimes called the upper chamber), thus reducing the pressure difference between the back side of the magnetron sputtering target assembly 30 and the sputtering surface 34 under high vacuum. The cooling channel 42 not only reduces the risk of deformation of the planar target 32 ​​but also improves its cooling efficiency by controlling the flow rate of the coolant.

[0097] The backplate 38 is connected to the planar target 32. The specific connection method between the backplate 38 and the planar target 32 ​​can be configured according to different usage requirements. For example... Figures 5 to 8As shown, in some embodiments, to improve the connection stability between the backplate 38 and the planar target 32, the backplate 38 can be welded to the target connection surface 36. The bonding interface between the planar target 32 ​​and the backplate 38 can be welded together by brazing, hard brazing, or indium bonding. The coefficients of thermal expansion of the planar target 32 ​​and the backplate 38 should be matched as much as possible. It should be noted that in the magnetron sputtering process of TGV (Through Glass Through-Video) technology, local high temperatures are prone to occur between the planar target 32 ​​and the backplate 38 under high power. The melting point of indium used for indium bonding of the target material is 156.6°C. On the one hand, the local high temperature situation in the TGV process of a large-area planar target 32 ​​greatly increases the risk that the indium bonding of the target material will fail due to excessive temperature; on the other hand, the shear stress formed by the difference in the coefficients of thermal expansion between the planar target 32 ​​and the backplate 38 may also cause the indium bonding to fail. The multiple cooling channels 42 can quickly reduce the temperature of the backplate 38 and the planar target 32, reducing the risk of connection failure due to excessive temperature. It is understandable that, since indium bonding melts at temperatures exceeding its melting point, when the planar target 32 ​​and the backplate 38 are connected via indium bonding, the magnetron sputtering target assembly 30 can be used to separate the backplate 38 and the planar target 32 ​​by heating the bonding interface at high temperature after use, thus enabling the backplate 38 to be recycled multiple times.

[0098] The extension path of the cooling channel 42 between the coolant inlet 44 and the coolant outlet 46 can be configured according to the cooling requirements of the planar target 32. Specifically, the cooling channel 42 can be configured as a serpentine, U-shaped, or other suitable shape. The close arrangement of the cooling channels 42 on the back plate 38 helps to increase the coolant coverage area and improve the coolant cooling efficiency. Figure 5 As shown, in some embodiments, the back plate 38 and the cover plate 40 together define a cooling channel 42, and a coolant inlet 44 and a coolant outlet 46 corresponding to the cooling channel 42. One end of the cooling channel 42 is connected to the coolant inlet 44, and the other end is connected to the coolant outlet 46. The cooling channel 42 extends from the coolant inlet 44 to the coolant outlet 46 by a bend. The bend in the cooling channel 42 can effectively increase the coverage area of ​​a single cooling channel 42, increase the contact area between the coolant and the cooled back plate, and improve the heat exchange efficiency. The cooling channel 42 is connected to the coolant inlet 44 and the coolant outlet 46. The distance between the coolant inlet 44 and the coolant outlet 46 can vary depending on the requirements for coolant entry and exit. Specifically, the coolant inlet 44 and the coolant outlet 46 can be arranged opposite each other or adjacent to each other; no limitation is made here.

[0099] The size and shape of the cover plate 40 can be configured according to the requirements of the cooling channel 42. In some embodiments, the cover plate 40 is configured as a bent flat plate adapted to the cooling channel 42, and the cover plate 40 is inlaid with the back plate 38 along the extension path of the cooling channel 42. In a second embodiment of the invention, as Figures 9 to 12 As shown, the cover plate 40 is a simple square or circular flat plate without internal bends. The entire flat cover plate covers and connects to the back plate 38. That is, the cover plate 40 can be configured as a flat plate in any shape that conforms to the cooling channel 42, such as a serpentine or U-shape; it can also be a simple, unbent, square or circular flat plate. The connection between the cover plate 40 and the back plate 38 can also be achieved through welding or bolting. The sealing of the connection between the cover plate 40 and the back plate 38 can be achieved through welding or sealing rings, etc. Specific details will be described later and will not be repeated here. Figure 5 , Figure 10 As shown, in some embodiments, the cover plate 40 is configured as a plate with the same shape as the back plate 38. Specifically, along the first direction Z, the projection of the back plate 38 onto the projection plane has a first shape, and the projection of the cover plate 40 onto the projection plane has a second shape. The first shape and the second shape are similar, and the edge of the cover plate 40 is connected to the back plate 38. If the back plate 38 is configured as a circular plate, the cover plate 40 is configured as a circular plate; if the back plate 38 is configured as a square plate, the cover plate 40 is configured as a square plate. Similarly, the edge of the cover plate 40 is connected to the back plate 38, and the size of the cover plate 40 and the back plate 38 can be the same or different. The arrangement of the cover plate 40 and the back plate 38 to match their shapes can improve the arbitrariness of the cooling channel 42 arrangement and improve the convenience of connecting the cover plate 40 and the back plate 38.

[0100] The cover plate 40 and the back plate 38 together define at least two cooling channels 42, wherein the cavities of the cooling channels 42 can be recessed from the back plate 38, such as... Figure 7 and Figure 12 As shown; it can also be recessed from the cover plate 40, such as Figure 8 As shown; or it can be recessed by the back plate 38 and the cover plate 40 together; there are no restrictions here, as long as a cooling channel 42 for coolant to flow can be formed between the cover plate 40 and the back plate 38. Figure 6 , Figure 7 , Figure 8 , Figure 10 , Figure 11 as well as Figure 12 As shown, in some embodiments, the back plate 38 has a back plate connecting surface 48, and the cover plate 40 has a cover plate connecting surface 50. The cover plate connecting surface 50 and the back plate connecting surface 48 together define a cooling channel 42. The back plate connecting surface 48 is recessed to the side opposite to the cover plate connecting surface 50 to form the cooling channel 42. Figure 7 and Figure 12As shown, correspondingly, the cover plate connecting surface 50 can be configured as a plane or as a wall surface with a groove. The groove of the cover plate connecting surface 50 communicates with the groove of the back plate connecting surface 48, thereby forming the same connecting channel. In some embodiments, the back plate connecting surface 48 and the cover plate connecting surface 50 together define a cooling channel 42, wherein the cover plate connecting surface 50 is recessed to the side opposite to the back plate connecting surface 48 to form the cooling channel 42, such as... Figure 8 As shown, the backplate connecting surface 48 can be either a flat surface or a wall surface with grooves, which will not be elaborated further here. The grooves forming the cooling channels 42 on the backplate 38 help improve the cooling efficiency of the coolant on both the backplate 38 and the target material; the grooves forming the cooling channels 42 on the cover plate 40 help reduce the material used in the backplate 38, lower its manufacturing cost, and also facilitate increasing the welding depth of the cover plate 40, thereby improving structural strength and sealing quality. Specifically, the arrangement of the grooves can be selected according to usage requirements, and is not limited here.

[0101] like Figure 7 , Figure 8 and Figure 12 As shown, when the cooling channel 42 is relatively wide, coolant may stagnate within it. The magnetron sputtering target assembly 30 can incorporate a diversion block 52 within the cooling channel 42. This diversion block 52 can divide the cooling water channel into two, three, or more branches 53, thereby reducing the risk of coolant stagnation. In some embodiments, the plate and cover plate 40 together define a coolant inlet 44 and a coolant outlet 46 corresponding to the cooling channel 42. One end of the cooling channel 42 is connected to the coolant inlet 44, and the other end is connected to the coolant outlet 46. The magnetron sputtering target assembly 30 also includes a diversion block 52 disposed within the cooling channel 42, so that the cooling channel 42 forms at least two branches 53. The diversion block 52 can divert the coolant only in a portion of the cooling channel 42, or it can divert the coolant from the coolant inlet 44 to the coolant outlet 46. The cooling channel 42 can have multiple diversion blocks 52, and these blocks 52 may not be interconnected. The number of tributaries 53 in different areas within the cooling channel 42 can also be different; there is no restriction here.

[0102] like Figures 13 to 17As shown, in the third embodiment of the present invention, to avoid separation between the planar target 32 ​​and the backing plate 38, the backing plate 38 can be integrally formed with the planar target 32 ​​and made of the same material. The large-area planar target 32 ​​typically must be fixed to the backing plate 38. The backing plate 38 is generally used to provide structural support, facilitate target cooling during thin film deposition, control the performance of the deposited thin film, and reduce costs. The strength and uniformity of the adhesion between the target and the backing plate 38, as well as the final flatness of the target and the backing plate 38, are crucial. In the prior art, the stress between the target with a large surface area and the backing plate 38 can also be significant. These stresses are largely due to the large difference between the thermal expansion coefficients of the target and the backing plate 38 material. Therefore, preferably, the backing plate 38 is made of a material with a small difference in thermal expansion coefficient compared to the planar target 32. Furthermore, the backing plate 38 can be made of the same material as the target; specifically, the backing plate 38 can be integrally formed with the planar target 32. The backplate 38 is integrally formed on the planar target 32, which can effectively reduce the risk of connection failure between the backplate 38 and the planar target 32 ​​under high shear stress or high temperature.

[0103] The connection method between the cover plate 40 and the back plate 38 can also be selected according to different usage requirements. For example... Figure 7 , 8 as well as Figure 12 As shown, in some embodiments, the cover plate 40 can be welded to the back plate 38. The back plate 38 and the cover plate 40 withstand the pressure of the coolant and provide a seal through the welding of the back plate connecting surface 48 and the cover plate connecting surface 50. Various welding methods are possible. When the cover plate 40 is welded to the back plate 38, it can be achieved through friction stir welding, brazing, or other welding processes. The back plate 38 has a back plate connecting surface 48 on the side facing away from the planar target 32. The cover plate 40 abuts against the back plate connecting surface 48; that is, the back plate connecting surface 48 is the contact surface between the back plate 38 and the cover plate 40. It is understood that the contact surface can include a vertical contact surface and a horizontal contact surface. Specifically, the wall surface perpendicular to the first direction Z is the horizontal contact surface, and the contact surface parallel to the first direction Z is the vertical direct contact surface. Specifically, if the back plate connecting surface 48 defines a groove for placing the cover plate 40, the cover plate 40 can abut against both the vertical and horizontal contact surfaces within the groove. The welding position between the cover plate 40 and the back plate 38 can be located only on the vertical contact surface, while at the horizontal contact surface, the cover plate 40 can simply abut against the back plate 38 or be separated by a small gap. The welding between the cover plate 40 and the back plate 38 needs to meet the sealing requirements of the coolant in the cooling channel 42, and must be able to withstand the high pressure of the coolant. In addition, it also needs to be able to withstand the pressure difference between the vacuum pressure and atmospheric pressure on the sputtering surface 34 side of the planar target 32.

[0104] Preferably, such as Figure 6 , Figure 7 and Figure 8As shown, in some embodiments, the backplate connecting surface 48 and the cover plate connecting surface 50 are joined together by an inlay method along the first direction Z, that is, by inlaying and welding the vertical direct contact surfaces parallel to the first direction Z. Each cooling channel has corresponding inlay surfaces on both sides. The inlay surface portion of the backplate connecting surface 48 and the cover plate connecting surface 50 along the first direction Z becomes the main weld bead to withstand the pressure of the coolant and provide a seal. A portion of the backplate connecting surface 48 and the cover plate connecting surface 50 perpendicular to the first direction Z (that is, parallel to the sputtering surface 34) is a contact surface, i.e., the wall surface perpendicular to the first direction Z is a horizontal contact surface, which can be a welded connection surface or an unwelded contact surface; another portion is a non-contact surface, becoming the inner surface of the cooling channel. For example... Figure 9 , Figure 10 , Figure 11 and Figure 12 As shown, in some embodiments, the cover plate connecting surface 50 is only connected to the back plate 38 around the periphery of the multiple cooling channels. Figure 12 The cover plate 40 shown is a flat plate without any inlay spacing. It is not connected to the back plate 38 on both sides of a single cooling channel. Correspondingly, the welding connection between the cover plate 40 and the back plate 38 is achieved by welding the connecting surfaces (back plate connecting surface 48 and cover plate connecting surface 50) perpendicular to the first direction Z on both sides of the cooling channel to withstand the pressure of the coolant and for sealing.

[0105] like Figure 16 , Figure 17 , Figure 22 as well as Figure 23 As shown, in the third embodiment of the present invention, the cover plate 40 is connected to the back plate 38 by bolts or screws. Specifically, the magnetron sputtering target assembly 30 also includes a connecting bolt 56, one end of which is connected to the cover plate 40 and the other end to the back plate 38. Similarly, the bolted connection between the cover plate 40 and the back plate 38 needs to withstand the high pressure of the coolant and the pressure difference between the vacuum chamber on the sputtering surface 34 side of the planar target 32 ​​and atmospheric pressure. The bolted connection is less affected by temperature and still has good stability in scenarios with high target power of large-area planar targets 32. Moreover, the bolted connection is convenient to install and disassemble, facilitating the recycling of the cover plate 40. It should be noted that when the cover plate 40 and the back plate 38 are connected by bolts, the sealing of the cooling channel 42 can be achieved by sealing rings or the like, which is not limited here.

[0106] The cover plate 40 and the back plate 38 together define the cooling channel 42, which is used to transport coolant. The sealing of the cooling channel 42 can be achieved by welding, adding sealing rings, etc. Figure 16As shown, in some embodiments, the magnetron sputtering target assembly 30 further includes a sealing component 54. The sealing component 54 is used to prevent coolant leakage from the cooling channel 42 to the back and sides of the magnetron sputtering target assembly 30, which could damage the deposition equipment. It is understood that the back side refers to the side opposite the sputtering surface 34 of the planar target 32, and the side refers to the side of the planar target 32 ​​perpendicular to the sputtering surface 34. The sealing component 54 can be configured as any suitable rubber sealing ring, such as nitrile rubber, silicone rubber, or butyl rubber. The location of the sealing component 54 can also vary depending on the connection position and method between the cover plate 40 and the back plate 38. The cooling channel 42 is located within the cover plate 40 and the back plate 38, and the area opposite to the cooling channel 42 is the edge of the cover plate 40 and the back plate 38. The sealing component 54 is located within the cover plate 40 and the back plate 38 along the boundary of the cooling channel 42, or it can be located at the edge of the cover plate 40 and the back plate 38 along the edge of the contact surface between the back plate 38 and the cover plate 40. It should be noted that the magnetron sputtering target assembly 30 has a connecting component. The connecting component can be located within the back plate 38 and the cover plate 40, or it can be located at the edge of the cover plate 40 and the back plate 38. When the connecting component is located within the cover plate 40 and requires sealing, a sealing ring can also be arranged around the connecting component. Specifically, as shown... Figures 13 to 17 As shown, in some embodiments, the sealing component 54 includes a cooling channel sidewall sealing ring 58 and a cooling channel sidewall sealing groove 60 defined by the cover plate 40 and the back plate 38, with the cooling channel sidewall sealing ring 58 disposed in the cooling channel sidewall sealing groove 60. That is, the cooling channel sidewall sealing ring 58 and the cooling channel sidewall sealing groove 60 are disposed along the edge of the cooling channel 42. This arrangement helps to completely confine the coolant within the designated flow channel, facilitating coolant flow control. Figure 18 , Figure 22 As shown, in some embodiments, the sealing component 54 includes a peripheral sealing ring 62. The cover plate 40 and the back plate 38 together define a peripheral sealing groove 64. The peripheral sealing groove 64 is disposed along the edge of the contact surface between the cover plate 40 and the back plate 38, and is spaced from the cooling channel 42. The peripheral sealing ring 62 is disposed in the peripheral sealing groove 64. That is, the peripheral sealing ring 62 is disposed at the edge of the contact area between the cover plate 40 and the back plate 38. At this time, the coolant can not only flow in the cooling channel 42, but if there is a gap between the cover plate 40 and the back plate 38 communicating with the cooling channel 42, the coolant can flow into the corresponding gap. Figures 18 to 23As shown, in the fourth embodiment of the present invention, the magnetron sputtering target assembly 30 further includes a connecting bolt 56, one end of which is connected to the cover plate 40 and the other end to the back plate 38. The sealing component 54 includes a connecting bolt sealing ring 66. The cover plate 40 and the back plate 38 together define a connecting bolt sealing groove 68, which surrounds the connecting bolt 56. The connecting bolt sealing groove 68 is generally circular, and the connecting bolt sealing ring 66 is disposed within the connecting bolt sealing groove 68. The connecting bolt sealing ring 66 improves the sealing performance of the connection between the cover plate 40 and the back plate 38. It should also be noted that, as... Figure 19 As shown, a sealing surface 69 is provided on the outer edge of the cover plate for vacuum sealing of the upper chamber on the back of the target material, which is explained in detail below.

[0107] A second aspect of this application also provides a thin film deposition apparatus 70, such as... Figure 24 As shown. The thin film deposition apparatus 70 includes a magnetron sputtering target assembly 30 according to any of the above embodiments. The thin film deposition apparatus 70 includes a thin film deposition chamber 72, a magnetron sputtering target assembly 30, and a substrate stage 74. The magnetron sputtering target assembly 30 has a large-area planar target 32, which is disposed facing the large-area substrate stage 74. The substrate stage 74 is used to hold a large-area substrate 76. A main power supply 78 applies sputtering power to the planar target 32. The main power supply 78 is generally a DC power supply. In some applications, the main power supply 78 is an RF power supply, especially when the planar target 32 ​​is made of a non-conductive material. A flow meter 80 controls the flow rate of the process chamber and controls the process gas pressure via a vacuum pump 82 and a gate valve. The target is positioned directly above the substrate stage 74. The magnetron 84 is movable relative to the target under the drive of a drive device (not shown). The magnetron 84 is positioned above the target, meaning the magnetron assembly is located on the side of the magnetron sputtering target assembly 30 facing away from the substrate stage 74. A movable upper chamber 86 may also be provided at the top of the thin film deposition chamber 72, allowing the user to open the chamber for easy replacement of the magnetron sputtering target assembly 30 and maintenance of the thin film deposition equipment 70. A sealing ring (not shown in the figure) may be provided between the thin film deposition chamber 72 and the upper chamber 86 to prevent the thin film deposition chamber 72 from communicating with the atmospheric environment.

[0108] The planar target 32 ​​is generally a conductor. The main power supply 78 is electrically connected to the planar target 32, which is located at the target mounting position, via a conductive wire. The main power supply 78 can supply power to the planar target 32. Figure 24 As shown, the negative terminal of the main power supply 78 is connected to the planar target 32, and the positive terminal of the main power supply 78 is grounded. The inner wall surface of the thin film deposition cavity 72 is also grounded. In this way, when the main power supply 78 supplies power to the planar target 32, an electric field is formed between the planar target 32 ​​and the inner wall surface of the thin film deposition cavity 72. The substrate stage 74 used to support the substrate 76 can be grounded, electrically levitated, or subjected to an applied radio frequency power supply bias.

[0109] The thin film deposition apparatus 70 may also include a flow meter 80. The flow meter 80 is connected to the thin film deposition chamber 72 and can be connected to an external gas source. The external gas source is a container storing working gas and is connected to the flow meter 80 via a pipe. The process gas provided by the external gas source can be argon. When the flow meter 80 is activated, the process gas can be delivered into the interior of the thin film deposition chamber 72; and the flow rate of the working gas can also be regulated by the flow meter 80.

[0110] The thin film deposition apparatus 70 may also include a vacuum pump 82. The vacuum pump 82 is connected to the thin film deposition chamber 72 and is used to remove gases from the thin film deposition chamber 72, including air and process gases. During the thin film deposition process on the substrate 76 by the thin film deposition apparatus 70, the internal chamber of the thin film deposition chamber 72 is isolated from the atmospheric environment, and the interior of the thin film deposition chamber 72 is approximately a vacuum. The vacuum pump 82 can remove gases from the thin film deposition chamber 72, thereby achieving a vacuum state in the thin film deposition chamber 72 and maintaining the vacuum level within the thin film deposition chamber 72 within a suitable range.

[0111] The thin film deposition apparatus 70 also includes an insulating block 88 and a mask. The mask is detachably mounted inside the thin film deposition chamber 72 and is replaceable. The mask covers a portion of the inner wall of the thin film deposition chamber 72 to prevent atoms sputtered from the planar target 32 ​​from adhering to the inner wall of the thin film deposition chamber 72. Two masks are provided, namely an upper mask 90 and a lower mask 92. A substrate clamp 94 presses down on the periphery of the substrate 76 during thin film deposition. The insulating block 88 is made of insulating material. The bottom surface of the insulating block 88 contacts the upper mask 90, and the top surface of the insulating block 88 contacts the edge of the planar target 32. The insulating block 88 supports the edge of the planar target 32 ​​and separates the upper mask 90 and the target material. The mask can be grounded or electrically suspended, as long as the plasma can "find" the grounded surface to form a complete electrical circuit.

[0112] The working principle of the thin film deposition equipment 70 is as follows. Process gas, such as argon, is introduced into the thin film deposition chamber 72. The main power supply 78 supplies power to the planar target 32, thereby generating an electric field inside the thin film deposition chamber 72. This electric field ionizes at least a portion of the argon gas. Specifically, electrons move in a spiral motion on the target surface under the influence of the electric and magnetic fields, or move from the target towards the substrate 76 or the mask. During the electron movement, electrons collide with argon atoms, causing the argon atoms to ionize and produce argon ions (Ar+) and new electrons. Under the influence of the electric field, the positively charged argon ions move towards the planar target 32 ​​and bombard the target surface, causing sputtering. The sputtered neutral target atoms, or ions sputtered and ionized during their passage through the plasma, are deposited on the substrate 76, thus forming a relatively uniform thin film on the surface of the substrate 76. The electrons generated during sputtering and during collisions are used to form and maintain plasma on the target surface, thereby enabling the process of argon ionization and argon ion bombardment of the target to be repeated, thus achieving continuous magnetron sputtering thin film deposition.

[0113] Electrons generated during target sputtering, electrons generated from the ionization of argon atoms, and electrons generated from the ionization of sputtered neutral atoms are all subject to electric and magnetic fields. These electrons drift in the direction indicated by E (electric field) × B (magnetic field) (referred to as E×B drift), and their trajectory approximates a cycloid. If the magnetic field provided by the magnetron sputtering assembly is a toroidal magnetic field, the electrons move in a toroidal spiral motion on the target surface along an approximate cycloid trajectory. These electrons not only have long paths but are also confined to a plasma region close to the target surface. Furthermore, in this region, argon atoms ionize into a large number of argon ions, which bombard the target, thus achieving a high deposition rate.

[0114] When the target power is relatively high and the size of the toroidal magnetron 84 is relatively small, the toroidal plasma density is relatively high. Only then can the sputtered target atoms collide with Ar+ and be ionized during their passage through the plasma. The deep hole trench filling material is generally a conductive metal; therefore, the ionization of target atoms is usually called metal ionization to distinguish it from the ionization of chemically inert process gases, such as Ar. If the metal ionization is insufficient, the angle between the unionized target atoms and the direction along the deep hole or trench sidewall may be large. The target atoms will fall onto the outer wall of the empty trench and cannot be deposited on the sidewall or bottom of the deep hole or trench. These target atoms with large angles to the deep hole extension direction or trench sidewall will accumulate at the opening of the deep hole or trench. If the opening size is small, it will even seal the opening, causing defects within the deep hole or trench. These target atoms with large angles to the trench sidewall can be filtered out by the collimator 96. A DC bias 98 can be applied to the collimator 96.

[0115] Once the target atoms are ionized by magnetron sputtering, they can be guided by the electromagnetic coil 100 or a permanent magnet to prevent them from being lost onto the mask. The magnetic field of the electromagnetic coil 100 or the permanent magnet pushes the metal ions towards the center of the cavity, or towards the side away from the mask. The electromagnetic coil 100 or the permanent magnet allows the metal ions to move towards the deep hole or trench in a direction perpendicular to the substrate 76, that is, along the direction of the deep hole extension or parallel to the trench sidewall. When the metal ions are close to the substrate 76, they are attracted and accelerated by the bias voltage of the RF power supply 102 applied to the substrate stage 74, and finally deposited on the upper surface of the substrate 76 and the sidewalls and bottom of the deep hole or trench. The RF power supply 102 is connected to the substrate stage 74 through a matching adapter 104.

[0116] Whether it's the conventional Ti or Cu thin film deposition process for advanced glass panel packaging, the Ti or Cu thin film deposition process for the seed layer (i.e., target) of TGV (Through Glass Via) technology, or other rectangular panel thin film deposition processes, all require meeting the cooling requirements of the large-area planar target 32. Thanks to the improvements to the magnetron sputtering target assembly 30 described above, the magnetron sputtering target assembly 30 of this embodiment has the same technical effects as the aforementioned magnetron sputtering target assembly 30, which will not be repeated here. It should be noted that if any directional indication (such as up, down, left, right, front, back, etc.) is involved in the embodiments of this invention, the directional indication is only used to explain the relative positional relationship and movement of the components in a specific posture. If the specific posture changes, the directional indication will also change accordingly.

[0117] Furthermore, if the embodiments of this invention involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the use of "and / or," "and / or," or "and / or" throughout the text implies three parallel solutions. For example, "A and / or B" includes solution A, solution B, or a solution where both A and B are satisfied simultaneously. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0118] The above are merely preferred embodiments of the present invention and do not limit the scope of the patent. Any equivalent structural transformations made using the contents of the specification and drawings of the present invention under the inventive concept of the present invention, or direct / indirect applications in other related technical fields, are included within the scope of patent protection of the present invention.

Claims

1. A magnetron sputter target assembly, characterized in that, The magnetron sputtering target assembly comprises: A planar target has sputtering surfaces oppositely arranged along a first direction and a target connecting surface, a projection surface being perpendicular to the first direction, a projection area S of the sputtering surfaces on the projection surface along the first direction satisfying: S≥0.2m 2 ; a back plate connected to the target connecting surface of the planar target; a cover plate connected to the back plate away from the planar target, the cover plate and the back plate together defining at least two cooling channels for circulating cooling liquid to cool the planar target.

2. The magnetron sputtering target assembly according to claim 1, wherein: the back plate and the cover plate together define a cooling liquid inlet corresponding to each cooling channel and a cooling liquid outlet corresponding to each cooling channel, one end of the cooling channel is in communication with the cooling liquid inlet, and the other end is in communication with the cooling liquid outlet, the cooling channel is bent from the cooling liquid inlet to the cooling liquid outlet.

3. The magnetron sputtering target assembly according to claim 2, wherein: the cover plate is configured as a bent plate body adapted to the cooling channel, the cover plate is connected to the back plate along the extension path of the cooling channel; or, in the first direction, the projection of the back plate on the projection surface has a first shape, and the projection of the cover plate on the projection surface has a second shape, the first shape is similar to the second shape, and the edge of the cover plate is connected to the back plate.

4. The magnetron sputtering target assembly according to claim 1, wherein: the back plate has a back plate connecting surface, and the cover plate has a cover plate connecting surface, the cover plate connecting surface and the back plate connecting surface together define the cooling channel; wherein the back plate connecting surface is recessed to the side away from the cover plate connecting surface; and / or, the cover plate connecting surface is recessed to the side away from the back plate connecting surface.

5. The magnetron sputtering target assembly according to claim 1, wherein: the back plate and the cover plate together define a cooling liquid inlet corresponding to each cooling channel and a cooling liquid outlet corresponding to each cooling channel, one end of the cooling channel is in communication with the cooling liquid inlet, and the other end is in communication with the cooling liquid outlet, the magnetron sputtering target assembly further comprises a flow divider, and the flow divider is arranged in the cooling channel to form at least two branch flows.

6. The magnetron sputtering target assembly according to claim 1, wherein: the back plate is welded to the target connecting surface; or, the back plate is integrally formed with the planar target.

7. The magnetron sputtering target assembly according to claim 1, wherein: the cover plate is welded to the back plate; or, the magnetron sputtering target assembly further comprises a connecting bolt, one end of the connecting bolt is connected to the cover plate, and the other end is connected to the back plate.

8. The magnetron sputtering target assembly according to claim 1, wherein: the magnetron sputtering target assembly further comprises a sealing component for limiting the leakage of the cooling liquid from the cooling channel to the back and side of the magnetron sputtering target assembly.

9. The magnetron sputtering target assembly according to claim 8, wherein: ​ ​ ​ The sealing component comprises a cooling channel side wall sealing ring, the cover plate and the back plate jointly define a cooling channel side wall sealing groove in communication with the cooling channel, and the cooling channel side wall sealing ring is arranged in the cooling channel side wall sealing groove; and / or, The sealing component comprises a peripheral sealing ring, the cover plate and the back plate jointly define a peripheral sealing groove arranged along the edge of the contact surface of the cover plate and the back plate and spaced from the cooling channel, and the peripheral sealing ring is arranged in the peripheral sealing groove; and / or, The magnetron sputtering target assembly further comprises a connecting bolt, one end of the connecting bolt is connected to the cover plate and the other end is connected to the back plate, the sealing component comprises a connecting bolt sealing ring, the cover plate and the back plate jointly define a connecting bolt sealing groove, the connecting bolt sealing groove is arranged around the connecting bolt, and the connecting bolt sealing ring is arranged in the connecting bolt sealing groove.

10. A thin film deposition apparatus, characterized by, The magnetron sputtering target assembly comprises any one of claims 1 to 9.

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