Wafer chuck, wafer bonding device and wafer edge deformation compensation method

Abstract

The invention relates to a wafer chuck, a wafer bonding device and a wafer edge deformation compensation method. The wafer chuck comprises a supporting member which is provided with a circular surface for supporting a wafer and is divided into a first area and a second area, and the part, located in the second area, of the supporting member is elastic; the supporting piece is arranged at the top of the disc body, the disc body is provided with a cavity corresponding to the second area and an air entraining channel communicated with the cavity, the air entraining channel is communicated with the suction device, and the adsorption holes are communicated with the cavity; the cavity forms a positive pressure state and a negative pressure state under the action of the suction device, and in the positive pressure state, the part, located in the second area, of the supporting piece protrudes towards the side away from the cavity so as to drive the edge of the wafer to move towards the side away from the cavity; in a negative pressure state, the part, located in the second area, of the supporting piece is recessed towards the interior of the cavity so as to drive the edge of the wafer to move towards the inner side of the cavity. According to the invention, the initial deformation of the edge of the wafer can be compensated, so that the distortion of the edge area of the wafer after bonding is reduced.

Description

Technical Field

[0001] This application relates to the field of semiconductor manufacturing technology, specifically to a wafer chuck, a wafer bonding device, and a wafer edge deformation compensation method. Background Technology

[0002] In 3D integrated circuit manufacturing, wafer bonding is the core process for achieving vertical integration and functionalization of multilayer devices. This process permanently bonds two or more wafers together through physical or chemical interactions, and its quality directly determines the electrical performance, mechanical reliability, and thermal management capabilities of the final stacked structure. Among the many key parameters for evaluating bonding quality, wafer bonding warpage / distortion is particularly important. It comprehensively reflects the overall flatness and stress distribution uniformity of the stacked wafers after bonding, and is a core indicator for measuring the quality of the bonding process. Furthermore, high wafer bonding warpage leads to poor uniformity of the bonded wafers in 3D integrated circuits, such as uneven contact at the bonding interface, poor compatibility with subsequent processes, and ultimately, significant dispersion in the electrical parameters and thermomechanical reliability of chips (dies) at different locations within the 3D integrated circuit, affecting overall product performance and yield.

[0003] Traditional bonding equipment typically employs integral vacuum adsorption or mechanical clamping chucks to apply uniform holding force to the wafer. The wafers to be bonded inherently possess warpage and thickness inhomogeneity, and during bonding, mismatches in the coefficients of thermal expansion (CTE) and differences in the thickness and uniformity of the bonding layers (such as dielectrics, metals, or polymers) introduce highly non-uniform interfacial stresses. However, traditional bonding equipment cannot accommodate the inherent defects of the wafers to be bonded, nor can it mitigate the uneven distribution of residual stress within the wafer during bonding, resulting in a deterioration in overall twist after bonding.

[0004] Therefore, a bonding device that can dynamically compensate for wafer edge deformation is needed. Summary of the Invention

[0005] The technical problem to be solved by this application is to provide a wafer chuck, a wafer bonding device, and a wafer edge deformation compensation method, which can compensate for the initial deformation of the wafer edge to reduce the wafer bonding twist and thus improve the uniformity of the bonded wafer.

[0006] According to a first aspect of the present application, a wafer chuck is provided. The wafer chuck includes: a support member having a circular surface for supporting a wafer, the support member being divided into at least two parts radially from the inside to the outside along the circular surface, including a first region located at the center of the circular surface and a second region located at the outermost edge of the circular surface, and the portion of the support member located in the second region being elastic and having an adsorption hole; a chuck body, the support member being disposed on the top of the chuck body, the chuck body having a chamber corresponding to the second region and an air intake channel communicating with the chamber, the air intake channel being used to communicate with a suction device, and the adsorption hole communicating with the chamber; wherein, the chamber forms a positive pressure state and a negative pressure state under the action of the suction device, in the positive pressure state, the portion of the support member located in the second region protrudes away from the chamber to drive the edge of the wafer to move away from the chamber; in the negative pressure state, the portion of the support member located in the second region is recessed into the chamber to drive the edge of the wafer to move into the chamber.

[0007] In one embodiment, the disc body is provided with a plurality of chambers and a plurality of air intake channels. All chambers are arranged sequentially along the circumference of the disc body, and each chamber is independent of the others. Each chamber is connected to one of the air intake channels.

[0008] In one embodiment, each of the air intake channels is connected to the suction device via an air pipe, and the air pipe is equipped with a control valve, which is used to control the opening and closing of the air pipe and to control the gas flow rate in the air pipe.

[0009] In one embodiment, the control valve has a communication unit that is connected to a host computer.

[0010] In one embodiment, the chamber is an annular cavity arranged around the disk body.

[0011] In one embodiment, the support member has a plurality of protrusions formed on the circular surface.

[0012] According to a second aspect of the embodiments of this application, a wafer bonding apparatus is provided, comprising: an upper chuck for adsorbing an upper wafer; a lower chuck, which is a wafer chuck as described in any of the preceding claims, the lower chuck being used to support a lower wafer, and the upper chuck and the lower chuck being disposed opposite to each other; a suction device connected to the air intake channel; and a control system connected to the suction device for controlling the operation of the suction device according to warpage information of the lower wafer, wherein the warpage information of the lower wafer includes the deformation direction of the lower wafer.

[0013] According to a third aspect of the embodiments of this application, a wafer edge deformation compensation method is provided, implemented using a wafer bonding apparatus. The wafer edge deformation compensation method in the bonding process includes: acquiring warpage information of a lower wafer; controlling the operation of a suction device based on the warpage information, including: when the warpage information includes the deformation direction of the lower wafer being upward, the suction device evacuates air from the chamber until the chamber forms the negative pressure state, causing the support portion located in the second region to cause the lower wafer to dent; when the warpage information includes the deformation direction of the lower wafer being downward, the suction device inflates the chamber until the chamber forms the positive pressure state, causing the support portion located in the second region to cause the lower wafer to bulge.

[0014] In one embodiment, the method further includes: when the warpage information includes the height information of the lower wafer being warped or sunken, the suction device controls the flow rate of air filling or evacuating the chamber according to the height information.

[0015] In one embodiment, when the disk body is provided with a plurality of independent chambers arranged along the circumferential direction of the disk body, the method further includes: when the warpage information includes the position information of the lower wafer being warped or sunken, the suction device controls the inflation or deflation of the chamber at the corresponding position according to the position information.

[0016] Compared with the prior art, the beneficial effects of this application are as follows: by setting a support member with a deformable second region, and setting a cavity and an air duct channel communicating with the cavity at the corresponding second region on the disk body, the air duct channel is used to communicate with a suction device, so that the state inside the cavity can be adjusted by suction or inflation (suction corresponds to the negative pressure state of the cavity, inflation corresponds to the positive pressure state of the cavity). The positive pressure state causes the part of the support member located in the second region to bulge upward (towards the side away from the cavity), and the negative pressure state causes the part of the support member located in the second region to bulge downward (towards the inside of the cavity). At the same time, the elastic deformation of the support member located in the second region is used to synchronously drive the deformation of the wafer edge, thereby compensating for the initial deformation of the edge of the wafer to be bonded, making the wafer surface tend to be flat, improving the wafer edge morphology, ensuring uniform contact between the wafer edge and the surface of another wafer during the bonding process, thereby effectively improving the bonding quality, greatly reducing the wafer bonding distortion, and improving the product yield. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of a wafer chuck according to an exemplary embodiment.

[0018] Figure 2 This is a schematic diagram illustrating the arching of a support member in a wafer chuck according to an exemplary embodiment.

[0019] Figure 3 This is a schematic diagram illustrating a recessed support in a wafer chuck according to an exemplary embodiment.

[0020] Figure 4 This is a schematic diagram of a wafer chuck according to another exemplary embodiment.

[0021] Figure 5 This is a schematic diagram of a wafer bonding apparatus according to an exemplary embodiment.

[0022] Explanation of reference numerals in the attached figures 1. Support component; 11. First region; 12. Second region; 13. Protrusion; 2. Disk body; 21. Chamber; 22. Gas venting channel; 3. Wafer; 31. Upper wafer; 32. Lower wafer; 4. Upper chuck; 5. Lower chuck; 6. Process chamber. Detailed Implementation

[0023] Unless otherwise defined, the technical or scientific terms used in this specification and claims shall have the ordinary meaning understood by one of ordinary skill in the art to which this application pertains. Specific embodiments of this application will be described below in conjunction with the accompanying drawings. It should be noted that, in order to provide a concise description, this specification cannot exhaustively describe all features of the actual embodiments. Without departing from the spirit and scope of this application, those skilled in the art can modify and substitute the embodiments of this application, and the resulting embodiments are also within the protection scope of this application.

[0024] In related technologies, before two wafers are bonded, the wafer edges often exhibit initial deformation, such as warping or sagging. Existing wafer bonding devices primarily rely on uniform clamping force to position the wafers. However, uniform clamping force cannot compensate for the initial deformation at the wafer edges; instead, it may "solidify" or exacerbate these deformations, leading to uneven distribution of residual stress within the wafers after bonding and a deterioration in overall distortion.

[0025] To address the aforementioned technical problems, this application provides a wafer chuck that can compensate for the initial deformation of the wafer edge, thereby reducing the twist of the wafer 3 after bonding.

[0026] refer to Figures 1 to 5In one specific embodiment, the wafer chuck includes: a support member 1 having a circular surface for supporting a wafer 3, the support member 1 being divided into at least two parts radially from the inside to the outside along the circular surface, including a first region 11 located at the center of the circular surface and a second region 12 located at the outermost part of the circular surface, and the portion of the support member 1 located in the second region 12 being elastic and having adsorption holes (not shown); a chuck body 2, the support member 1 being disposed on the top of the chuck body 2, the chuck body 2 having a cavity 21 corresponding to the second region 12 and a lead communicating with the cavity 21. The air passage 22 is used to communicate with the suction device (not shown), and the adsorption hole is connected to the chamber. The chamber 21 is formed into a positive pressure state and a negative pressure state under the action of the suction device. In the positive pressure state, the part of the support member 1 located in the second region 12 protrudes away from the chamber 21 to drive the edge of the wafer 3 to move away from the chamber 21. In the negative pressure state, the part of the support member 1 located in the second region 12 is recessed into the chamber 21 to drive the edge of the wafer 3 to move inward into the chamber 21.

[0027] It should be noted that the support 1 is the side of the chuck that contacts the wafer 3. The circular surface on the support 1 is used to directly support the wafer 3 and has elasticity in the second region 12. Thus, the part of the support 1 located in the second region 12 can undergo elastic deformation under air pressure, thereby adaptively compensating for the initial deformation of the wafer edge. When the edge of the wafer 3 to be bonded initially deforms upward, a negative pressure can be created by evacuating the chamber 21, causing the support member 1 of the second region 12 to be recessed downward and the edge of the wafer 3 to be bonded to move downward through the adsorption hole, so that the wafer 3 to be bonded becomes flat, that is, the bonding surface of the wafer 3 becomes flat, which facilitates bonding with another wafer 3; when the edge of the wafer 3 to be bonded initially deforms into a collapsed edge, that is, a concave shape, a positive pressure can be created by filling the chamber 21, causing the support member 1 of the second region 12 to be raised upward and the edge of the wafer 3 to be bonded to move upward, so that the wafer 3 to be bonded becomes flat.

[0028] In this embodiment, a cavity 21 is formed between the disk 2 and the support member 1. The state of the cavity 21 is adjusted by evacuating or inflating it (evacuation corresponds to a negative pressure state, and inflation corresponds to a positive pressure state). In the positive pressure state, the part of the support member 1 located in the second region 12 protrudes upward (towards the side away from the cavity 21), and in the negative pressure state, the part of the support member 1 located in the second region 12 is recessed downward (towards the interior of the cavity 21). At the same time, the deformation of the part of the support member 1 located in the second region 12 simultaneously drives the deformation of the wafer edge, thereby compensating for the initial deformation of the wafer edge, making the surface of the wafer 3 more flat, improving the wafer edge morphology, ensuring uniform contact between the wafer edge and the surface of another wafer 3 during the bonding process, thereby effectively improving the bonding quality, greatly reducing the twist of the wafer 3 after bonding, and improving the product yield.

[0029] In one embodiment, the chamber 21 is configured as a continuous annular cavity surrounding the disk body 2, i.e., the chamber 21 is a single annular channel. The annular channels are continuously distributed along the circumference of the disk body 2 to correspond to the entire outer peripheral edge of the wafer 3, and the annular channels are connected to the suction device through one or more evenly distributed air intake channels 22. This embodiment is more suitable for scenarios where the wafer edge deformation direction is the same and the deformation amplitude is uniform. For example, if the entire outer peripheral edge of the wafer 3 is upturned or sunken, air is injected or extracted into the chamber 21, so that the second region 12 on the support 1 interacts with the edge of the wafer 3, thereby compensating for the overall deformation of the wafer edge and making the surface of the wafer 3 flat.

[0030] In another implementation, refer to Figure 4 The disk body 2 is provided with multiple chambers 21 and multiple air intake channels 22. All chambers 21 are arranged sequentially along the circumference of the disk body 2, and each chamber 21 is independent of each other. Each chamber 21 is connected to an air intake channel 22. In this embodiment, each air intake channel 22 is independently connected to a suction device to achieve independent control of the air pressure state in each chamber 21. This allows for corresponding local compensation based on the deformation at different locations on the wafer edge, thus achieving corresponding compensation for multi-regional and non-uniform deformation at the wafer edge.

[0031] Specifically, the spacing between adjacent chambers 21 is small, so that multiple chambers 21 are arranged approximately around the edge of the wafer. Taking the deformation at a certain point on the edge of the wafer as an example, while other positions do not deform, the air pressure state of the corresponding chamber 21 can be adjusted individually. The corresponding chamber 21 refers to the chamber 21 that at least partially overlaps with the deformation position. The deformation of the corresponding chamber 21 causes the support 1 at that position to deform, thereby driving the local area of ​​the wafer edge to deform synchronously, achieving position-specific deformation compensation.

[0032] In one embodiment, each gas intake channel 22 is independently connected to the suction device via a gas pipe (not shown), and the gas pipe is equipped with a control valve (not shown). The control valve is used to control the opening and closing of the gas pipe and the gas flow rate in the gas pipe. When multiple independent chambers 21 are provided on the disk body 2, this embodiment achieves independent control of the gas pressure in each chamber 21 by independently controlling the control valve on each gas pipe. This allows for the control of the gas filling or suction flow rate corresponding to the different deformation amplitudes at different regions of the wafer edge, thereby controlling the gas pressure in the chamber 21 and matching (approximately matching) the deformation amplitude of the support member 1 at the corresponding position with the deformation amplitude of the wafer edge.

[0033] This configuration serves two purposes. First, when wafer 3 is placed on support 1 for adsorption and fixation, it ensures that the wafer edge is in close contact with the chuck, preventing unstable adsorption due to mismatched deformation amplitudes and thus affecting bonding quality. Second, before bonding, when the chuck performs deformation compensation on the wafer edge, the deformation amplitude of support 1 matches (is approximately the same) as the deformation amplitude of the wafer edge, ensuring that wafer 3 is as flat as possible after deformation compensation, and preventing excessive or insufficient compensation from affecting the flatness of wafer 3.

[0034] Specifically, taking the upward warping deformation of a local area at the edge of the wafer as an example, during deformation compensation, the opening of the control valve is adjusted according to the height of the upward warping deformation to adjust the air flow rate, so that the support 1 produces a corresponding depth of concave deformation. That is, the support 1 here can generate a corresponding adsorption force on the upward warping wafer edge. This adsorption force can pull the wafer edge of the local area downward, and the downward displacement is almost the same as the height of the upward warping deformation. This achieves the application of a compensation amount that is approximately the same as the deformation amplitude of the wafer edge, so that the wafer edge is approximately restored to an ideal flat state before bonding.

[0035] In one embodiment, the control valve has a communication unit (not shown) that is connected to a host computer (not shown). In this embodiment, the control valve can be a solenoid valve, which can be adjusted for on / off state and opening degree under the control of the host computer. The host computer opens and closes the control valve according to the production process (such as the process of wafer 3 being adsorbed by the chuck, or the process of the chuck compensating for the deformation of wafer 3 before bonding), and adjusts the opening degree of the control valve according to actual production needs (the position, direction, and amplitude of the deformation area at the edge of the wafer). The host computer refers to a computer system with computing and data processing capabilities, which is an existing component and will not be described in detail here.

[0036] In one implementation, reference Figure 4The support member 1 has multiple protrusions 13 formed on its circular surface. In this embodiment, all the protrusions 13 are evenly distributed in the first region 11 of the support member 1. When the wafer 3 is adsorbed and fixed on the support member 1, the wafer 3 contacts the protrusions 13 to form point support, so that an air gap is formed between the wafer 3 and the support member 1. This allows dust and other particles on the surface of the wafer 3 to be temporarily contained in the gap, avoiding the direct trapping of dust and other particles between the circular surface of the wafer 3 and the support member 1 due to surface support, which would damage the wafer 3.

[0037] According to a second aspect of the embodiments of this application, a wafer bonding apparatus is provided, with reference to... Figure 5 The wafer bonding apparatus includes: a process chamber 6; an upper chuck 4, placed in the process chamber 6, for adsorbing the upper wafer 31; a lower chuck 5, placed in the process chamber 6, employing a wafer chuck as described in any of the above embodiments, the lower chuck 5 supporting the lower wafer 32, and the upper chuck 4 and lower chuck 5 being arranged opposite to each other; a suction device, located outside the process chamber 6 and connected to the air intake channel 22; and a control system, connected to the suction device, for controlling the operation of the suction device according to the warpage information of the lower wafer 32, the warpage information of the lower wafer 32 including the deformation direction of the lower wafer 32.

[0038] It should be added that the wafer bonding device also includes structural components for providing the necessary physical conditions for wafer bonding, such as temperature, pressure, and vacuum, which will not be elaborated here.

[0039] In this embodiment, the upper chuck 4 can adopt a conventional upper chuck structure, or the upper chuck 4 can adopt the wafer chuck described in any of the above embodiments, which is not limited here; the upper chuck 4 and the lower chuck 5 respectively achieve adsorption and positioning of the upper wafer 31 and the lower wafer 32 to be bonded by vacuum adsorption; the control system has a communication module connected to the host computer, and the warpage information of the lower wafer 32 can be obtained in the pre-process of the bonding process. The warpage information includes, but is not limited to, the direction of the wafer edge deformation (upward or downward), the position of the deformation on the wafer circumference, and the magnitude of the upward or downward deformation. The control system can control the start and stop of the suction device and the suction parameters (gas extraction and gas filling flow rate) according to the above warpage information, and can also adjust the opening degree of the control valve on each gas venting channel 22 to achieve corresponding compensation for the edge deformation area of ​​the lower wafer 32.

[0040] According to a third aspect of the embodiments of this application, a wafer edge deformation compensation method is provided for use in a bonding process, implemented using the wafer bonding apparatus described in the above embodiments. The wafer edge deformation compensation method in the bonding process includes: acquiring warpage information of the lower wafer 32; controlling the operation of a suction device based on the warpage information, including: when the warpage information includes the deformation direction of the lower wafer 32 being upward, the suction device evacuates air from the chamber 21 until the chamber 21 forms a negative pressure state, causing the support member 1 located in the second region 12 to cause the lower wafer 32 to be concave; when the warpage information includes the deformation direction of the lower wafer 32 being downward, the suction device inflates air into the chamber 21 until the chamber 21 forms a positive pressure state, causing the support member 1 located in the second region 12 to cause the lower wafer 32 to be convex.

[0041] In this embodiment, before bonding, the edge deformation of the lower wafer 32 is pre-compensated based on the wafer edge deformation compensation method to improve the wafer edge morphology and ensure that the contact surface between the upper wafer 31 and the lower wafer 32 is a flat interface during bonding. First, it is determined whether the deformation direction in the warpage information is upward or downward. Second, the working state of the chamber 21 is adjusted according to the deformation direction. When the deformation direction is upward, the suction device is activated to evacuate the chamber 21, causing the support member 1 of the second region 12 to deform the wafer edge downward under negative pressure. When the deformation direction is downward, the suction device is controlled to inflate the chamber 21, causing the support member 1 of the second region 12 to rise upward under air pressure, causing the wafer edge to deform upward, thereby achieving compensation for the wafer edge deformation.

[0042] In one embodiment, the wafer edge deformation compensation method further includes: when the warpage information includes the height information of the upward or downward tilt of the lower wafer 32, the suction device controls the flow rate of air filling or evacuating the chamber 21 according to the height information. In this embodiment, the warpage information includes, but is not limited to, the height information of the upward or downward tilt of the lower wafer 32. The control system can adjust the flow rate of air filling or evacuating from the suction device, or adjust the opening degree of the control valve, according to the height information.

[0043] In one implementation, reference Figure 4When the disk body 2 is provided with multiple independent chambers 21 arranged along the circumference of the disk body 2, the wafer edge deformation compensation method further includes: when the warpage information includes the position information of the lower wafer 32 being warped or sunken, the suction device controls the filling or emptying of the corresponding chamber 21 according to the position information. This embodiment is applicable to embodiments with multiple independent chambers 21. Based on this embodiment, the suction device of the corresponding chamber 21 can be individually controlled to perform emptying or filling based on the position information (the position of the deformed area in the circumferential direction of the wafer 3) in the warpage information. The corresponding chamber 21 refers to the chamber 21 that at least partially overlaps with the wafer edge deformation area, so as to achieve independent adjustment of the deformation at different positions of the wafer edge; specifically, when a certain area of ​​the lower wafer 32 is warped and the adjacent area is sunken, the chamber 21 of the corresponding area can be independently controlled to perform emptying and filling respectively, thereby being compatible with the use of complex wafer edge deformation.

[0044] Optionally, the spacing between adjacent chambers 21 and the size of each chamber 21 can be determined according to actual process requirements, such as setting equal spacing between adjacent chambers 21, which is not limited here.

[0045] The above description of the embodiments is intended to enable those skilled in the art to understand and apply this application. It will be apparent to those skilled in the art that various modifications can be easily made to these embodiments, and the general principles described herein can be applied to other embodiments without creative effort. Therefore, this application is not limited to the embodiments described herein, and any improvements and modifications made by those skilled in the art based on the disclosure of this application without departing from the scope and spirit of this application are within the scope of this application.

Claims

1. A wafer chuck, characterized by, The application relates to a wafer chucking device, which comprises the following parts: a support with a circular surface for supporting a wafer, the support is divided into at least two parts along the radial direction of the circular surface from inside to outside, including a first area in the center of the circular surface and a second area at the outermost side of the circular surface, and the part of the support located in the second area is elastic and provided with adsorption holes; a disc body, the support is arranged on the top of the disc body, the disc body is provided with a cavity corresponding to the second area and an air channel connected with the cavity, the air channel is used for being connected with a suction device, and the adsorption holes are communicated with the cavity; wherein the cavity forms a positive pressure state and a negative pressure state under the action of the suction device, when the positive pressure state is formed, the part of the support located in the second area is bulged to the side far away from the cavity so as to drive the edge of the wafer to move to the side far away from the cavity; when the negative pressure state is formed, the part of the support located in the second area is concave to the inside of the cavity so as to drive the edge of the wafer to move to the inside of the cavity.

2. The wafer chuck of claim 1, wherein The disc body is provided with a plurality of cavities and a plurality of air channels, all the cavities are arranged along the circumferential direction of the disc body in sequence, and each cavity is independent of each other, and each cavity is communicated with one air channel.

3. The wafer chuck of claim 2, wherein, Each air channel is connected with the suction device through one air pipe, and the air pipe is provided with a control valve, the control valve is used for controlling the opening and closing of the air pipe and the gas flow in the air pipe.

4. The wafer chuck of claim 3, wherein, The control valve is provided with a communication unit connected with an upper computer.

5. The wafer chuck of claim 1, wherein The cavity is an annular cavity arranged around the disc body.

6. The wafer chuck of claim 1, wherein, The support is provided with a plurality of bulges on the circular surface.

7. A wafer bonding apparatus characterized by comprising: The application also relates to a wafer bonding device, which comprises the following parts: an upper chuck used for adsorbing an upper wafer; a lower chuck adopting the wafer chuck of any one of claims 1-6, the lower chuck is used for supporting a lower wafer, and the upper chuck and the lower chuck are arranged oppositely; a suction device connected with the air channel; a control system connected with the suction device, used for controlling the action of the suction device according to the warping information of the lower wafer, and the warping information of the lower wafer includes the deformation direction of the lower wafer.

8. A wafer edge deformation compensation method, characterized by, The application also relates to a wafer bonding method, which is implemented by using the wafer bonding device of claim 7, and the method comprises the following steps: obtaining the warping information of the lower wafer; controlling the action of the suction device according to the warping information, which comprises the following steps: when the warping information includes that the deformation direction of the lower wafer is upward warping, the suction device is used for sucking the air in the cavity until the cavity forms a negative pressure state, so that the part of the support located in the second area drives the lower wafer to be concave; when the warping information includes that the deformation direction of the lower wafer is downward warping, the suction device is used for filling the air in the cavity until the cavity forms a positive pressure state, so that the part of the support located in the second area drives the lower wafer to be bulged.

9. The wafer edge distortion compensation method of claim 8, wherein, The application also relates to a wafer bonding method, which is implemented by using the wafer bonding device of claim 7, and the method comprises the following steps: when the warping information includes the height information of the upward warping or downward warping of the lower wafer, the suction device is used for controlling the flow of the air filled or sucked in the cavity according to the height information.

10. The wafer edge distortion compensation method of claim 8, wherein, when the disc body is provided with a plurality of cavities which are independent of each other and arranged along the circumferential direction of the disc body, the method further comprises the following steps: When the warping information comprises position information of the upwarping or downwarping of the lower wafer, the suction device controls the inflation or suction of the chamber at the corresponding position according to the position information.

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