A chuck

Abstract

The application relates to the technical field of semiconductor detection, in particular to a chuck, which comprises a main body part, the main body part is provided with a bearing surface and a center through hole penetrating through the main body part along the thickness direction, the bearing surface comprises a first area and a second area surrounding the first area, and the first area surrounds the center through hole; a boss structure is arranged on the first area, and a sealing structure is arranged on the second area; wherein the boss structure comprises a plurality of circumferential boss groups, the corresponding circumferential radii of the circumferential boss groups are different and all have the same center as the center through hole, each circumferential boss group comprises a plurality of curved bosses arranged at intervals along the corresponding circumferences, and each boss extends along the corresponding circumference. The chuck provided by the application is beneficial to realizing higher adsorption force adsorption of wafers and ensuring that the wafers have higher flatness.

Description

Technical Field

[0001] This invention belongs to the field of semiconductor testing technology, and particularly relates to a chuck. Background Technology

[0002] During the overlay measurement process, the measurement speed needs to match the process speed of the lithography machine, and the measurement accuracy must be at the sub-nanometer level to correct the lithography process. During measurement, the wafer needs to be placed below the optical inspection system, and a chuck is used to move the wafer with high acceleration or deceleration. After the wafer is moved into position, it needs to quickly reach a nanometer-level stable position. Analysis has shown that for processes below 28nm nodes, higher measurement speeds and accuracy are required. Therefore, the platform that moves the wafer needs higher acceleration and higher positional stability. Currently, at least the acceleration of the platform moving the wafer is required to be no less than 2g (g is the acceleration due to gravity), and the in-situ stability of the wafer in a static state must be less than 1nm.

[0003] However, due to the rise of advanced packaging in recent years, advanced packaging processes have led to increasingly larger wafer warpage and more complex morphologies. For chucks, they need to be compatible with wafers with greater warpage. At the same time, during the overlay measurement process, if the flatness of the wafer surface after adsorption is poor, it will also negatively affect the measurement accuracy. Therefore, it is urgent to design a chuck that can be compatible with large warpage, has high flatness after adsorption, adapts to high acceleration movement, and has high in-situ stability. Summary of the Invention

[0004] In view of this, the present invention aims to provide a chuck that facilitates the adsorption of wafers with higher adsorption force and ensures that the wafers have a high degree of flatness.

[0005] To achieve the above objectives, the technical solution created by this invention is implemented as follows:

[0006] This invention provides a chuck, comprising: a main body having a bearing surface and a central through hole penetrating the main body along its thickness direction; the bearing surface including a first region and a second region surrounding the first region, the first region surrounding the central through hole; a boss structure located in the first region and a sealing structure located in the second region; wherein the boss structure includes multiple circumferential boss groups, each circumferential boss group having a different circumferential radius and all concentric with the central through hole; each circumferential boss group including multiple curved bosses arranged at intervals along a corresponding circumference, each boss extending along a corresponding circumference.

[0007] Furthermore, the first region includes a first annular region surrounding the central through hole, a group of circumferential bosses located in the first annular region is a first circumferential boss group, a boss in the first circumferential boss group is a first boss, a plurality of first circumferential boss groups are provided on the first annular region, the number of first bosses in each first circumferential boss group is the same, a first interval is between two adjacent first bosses in the first circumferential boss group, and the corresponding first intervals in each first circumferential boss group are aligned in the radial direction along the first annular region.

[0008] Furthermore, the first region also includes a second annular region surrounding the first annular region. The circumferential boss group located in the second annular region is a second circumferential boss group, and the boss in the second circumferential boss group is a second boss. Multiple second circumferential boss groups are provided on the second annular region. The number of second bosses in each second circumferential boss group is the same. There is a second interval between two adjacent second bosses in the second circumferential boss group. In the radial direction along the second annular region, the corresponding second intervals in each second circumferential boss group are aligned. The number of second bosses in the second circumferential boss group is greater than the number of first bosses in the first circumferential boss group.

[0009] Furthermore, in the radial direction along the second annular region, a portion of the second interval is aligned with the first interval.

[0010] Furthermore, the number of first protrusions in the first circumferential protrusion group is N, and the number of second protrusions in the second circumferential protrusion group is n×N, where n is an integer greater than 1.

[0011] Furthermore, the first annular region and the second annular region are separated by a first preset circle. The boss structure also includes N outer ring bosses. The N outer ring bosses are arranged at intervals along the first preset circle. In the radial direction along the first preset circle, the outer ring bosses are aligned with the middle part of the corresponding first boss in the adjacent first circumferential boss group.

[0012] Furthermore, the first region also includes a third annular region surrounding the second annular region. The circumferential boss group located in the third annular region is the third circumferential boss group, and the bosses in the third circumferential boss group are third bosses. Multiple third circumferential boss groups are provided on the third annular region. The number of third bosses in each third circumferential boss group is the same. There is a third interval between two adjacent third bosses in the third circumferential boss group. In the radial direction along the third annular region, the corresponding third intervals in each third circumferential boss group are aligned, and the third intervals are staggered from the second intervals. The number of third bosses in the third circumferential boss group is equal to the number of second bosses in the second circumferential boss group.

[0013] Furthermore, the middle portion of the first boss protrudes towards the central through hole; the middle portion of the second boss protrudes towards the central through hole; and the middle portion of the third boss protrudes away from the central through hole.

[0014] Furthermore, the third interval bisects the corresponding second protrusion.

[0015] Furthermore, the widths of the first intervals, the second intervals, and the third intervals are all the same, and the widths of the first, second, and third intervals are all the same.

[0016] Furthermore, the boss structure also includes multiple inner ring bosses, which are arranged circumferentially along the central through hole.

[0017] Furthermore, the interior of the main body has multiple spaced-apart hollow areas.

[0018] Furthermore, the height of the sealing structure is not less than the height of the boss structure.

[0019] Furthermore, the chuck is a one-piece molded structure, and it is manufactured using 3D printing technology.

[0020] Compared with the prior art, the present invention can achieve the following beneficial effects: The chuck provided by the present invention includes a main body, the interior of which is designed with multiple spaced grids, which not only helps to reduce the weight of the chuck but also ensures that the chuck has high structural strength. The bearing surface of the main body has a sealing structure and a boss structure located in the inner ring of the sealing structure. The boss structure includes multiple circumferential boss groups, each circumferential boss group including multiple curved bosses arranged along the circumference, and each boss extends along the corresponding circumference. In this way, when the gas between the wafer and the chuck is sucked up through the central through-hole, it can be achieved from the circumferential bosses closest to the central through-hole. A vacuum is established in the inner ring of the assembly, and the vacuum gradually diffuses to the outermost sealed structure. Adsorption force is formed from the center of the wafer to the edge, which makes the vacuum formation faster, reduces leakage, and increases the adsorption force. The curved protrusions are not limited to their circumference, which can reduce leakage caused by the height difference between the wafer surface and the corresponding area of ​​the circumference. In this way, multiple circumferential protrusions work together to achieve high adsorption force and high flatness for cup-shaped warped wafers, umbrella-shaped warped wafers, and wavy warped wafers, which is beneficial to improving the measurement accuracy and precision of overlay measurement. Attached Figure Description

[0021] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments and descriptions of the invention are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0022] Figure 1 A top view of a chuck as described in an embodiment of the present invention;

[0023] Figure 2 This is a partial structural diagram of the chuck described in an embodiment of the present invention. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and do not constitute a limitation thereof.

[0025] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other.

[0026] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this invention. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0027] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art will understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0028] The invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0029] refer to Figures 1 to 2The present invention provides a chuck, comprising: a main body having a bearing surface 101 and a central through hole 130 extending through the main body along the thickness direction; the bearing surface 101 including a first region and a second region surrounding the first region, the first region surrounding the central through hole 130; a boss structure located in the first region and a sealing structure 102 located in the second region; wherein the boss structure includes a plurality of circumferential boss groups, each circumferential boss group having a different circumferential radius and all being concentric with the central through hole 130; each circumferential boss group including a plurality of curved bosses arranged at intervals along the corresponding circumference, each boss extending along the corresponding circumference.

[0030] In some embodiments, the height of the sealing structure 102 is not less than the height of the boss structure.

[0031] In some embodiments, the sealing structure 102 is annular, and the inner ring of the sealing structure 102 is concentric with the central through hole 130. In other words, it is concentric with the circumferences corresponding to each circumferential boss group.

[0032] It should be noted that the chuck is used to adsorb the wafer and move the wafer. The boss structure is located in the inner ring of the sealing structure 102. The side of the boss structure and the sealing structure 102 away from the bearing surface 101 is used to support the wafer. When the chuck adsorbs the wafer, a vacuum is formed between the side of the wafer facing the chuck, the sealing structure 102 and the bearing surface 101, thereby creating a negative pressure adsorption on the wafer. The boss structure is used to support the wafer.

[0033] In some embodiments, the central through hole 130 penetrates the body portion along the thickness direction of the body portion.

[0034] In some embodiments, the shapes and sizes of the bosses in the same circumferential boss group are all the same.

[0035] In some embodiments, a plurality of circumferential bosses are evenly arranged between the central through hole 130 and the sealing structure 102.

[0036] In some embodiments, the spacing between two adjacent circumferential boss groups is in the range of 2.8mm to 3mm, and the spacing between two adjacent bosses in the same circumferential boss group is in the range of 2.3mm to 2.7mm.

[0037] In some embodiments, the shape of the cross-section of the boss along its thickness direction can be trapezoidal. This avoids the boss edges being too sharp, thereby reducing scratches on the wafer to some extent.

[0038] In some embodiments, the main body also has a plurality of ejector pin holes 131 and a plurality of mounting holes 132. The ejector pin holes 131 and the mounting holes 132 both penetrate the main body along the thickness direction of the main body. The ejector pin holes 131 are used to provide liftable ejector pins, which are used to lift the wafer so that the robot can pick up and place the wafer. After the robot places the wafer on the chuck, the ejector pins descend so that the wafer falls on the chuck. The mounting holes 132 are used to provide mounting members, which are used to mount the chuck to the drive mechanism. The drive mechanism is used to drive the chuck to rotate along the axial direction of the chuck and to drive the chuck to translate in a direction parallel to the bearing surface 101.

[0039] In one specific embodiment, the main body has three ejector pin holes 131 and three mounting holes 132. The line connecting the centers of the three ejector pin holes 131 forms a first equilateral triangle, the center of which coincides with the center of the central through hole 130. The line connecting the centers of the three mounting holes 132 forms a second equilateral triangle, the center of which coincides with the center of the central through hole 130. The side length of the first equilateral triangle is greater than the side length of the second equilateral triangle.

[0040] Furthermore, the first region includes a first annular region surrounding the central through hole 130. The circumferential boss group located in the first annular region is a first circumferential boss group, and the boss in the first circumferential boss group is a first boss 111. Multiple first circumferential boss groups are provided on the first annular region. The number of first bosses 111 in each first circumferential boss group is the same. There is a first interval between two adjacent first bosses 111 in the first circumferential boss group. In the radial direction along the first annular region, the corresponding first intervals in each first circumferential boss group are aligned.

[0041] In some examples, the number of first bosses 111 in each first circumferential boss group is 12.

[0042] Furthermore, the middle portion of the first boss 111 protrudes towards the central through hole 130.

[0043] Furthermore, the first region also includes a second annular region surrounding the first annular region. The circumferential boss group located in the second annular region is a second circumferential boss group, and the bosses in the second circumferential boss group are second bosses 112. Multiple second circumferential boss groups are provided on the second annular region. The number of second bosses 112 in each second circumferential boss group is the same. There is a second interval between two adjacent second bosses 112 in the second circumferential boss group. In the radial direction along the second annular region, the corresponding second intervals in each second circumferential boss group are aligned. The number of second bosses 112 in the second circumferential boss group is greater than the number of first bosses 111 in the first circumferential boss group.

[0044] Furthermore, the middle portion of the second boss 112 protrudes towards the central through hole 130.

[0045] Furthermore, in the radial direction along the second annular region, a portion of the second gap is aligned with the first gap. This guides the airflow in the radial direction, increasing the speed at which vacuum diffuses outward from the central through-hole 130, thereby reducing air leakage and significantly enhancing the adsorption capacity for wafers with large wavy warps.

[0046] In some embodiments, all the first intervals have aligned second intervals in the radial direction along the second annular region.

[0047] Furthermore, the number of first protrusions 111 in the first circumferential protrusion group is N, and the number of second protrusions 112 in the second circumferential protrusion group is n×N, where n is an integer greater than 1. In some examples, n is 2.

[0048] Furthermore, the first annular region and the second annular region are separated by a first preset circle. The boss structure also includes N outer ring bosses 114, which are arranged at intervals along the first preset circle. In the radial direction along the first preset circle, the outer ring bosses 114 are aligned with the middle portion of the corresponding first bosses 111 in the adjacent first circumferential boss group. The outer ring bosses 114 can fill the area where the distance between the first bosses 111 and the second bosses 112 is large, avoiding the negative impact of excessive spacing between the bosses on the flatness of the adsorbed wafer.

[0049] Furthermore, the first region also includes a third annular region surrounding the second annular region. The circumferential boss group located in the third annular region is the third circumferential boss group, and the boss in the third circumferential boss group is the third boss 113. Multiple third circumferential boss groups are provided on the third annular region. The number of third bosses 113 in each third circumferential boss group is the same. There is a third interval between two adjacent third bosses 113 in the third circumferential boss group. In the radial direction along the third annular region, the corresponding third intervals in each third circumferential boss group are aligned, and the third intervals are staggered from the second intervals. The number of third bosses 113 in the third circumferential boss group is equal to the number of second bosses 112 in the second circumferential boss group.

[0050] In some embodiments, in the first annular region, the spacing between any two adjacent first circumferential protrusion groups is the same; in the second annular region, the spacing between any two adjacent second circumferential protrusion groups is the same; and in the third annular region, the spacing between any two adjacent third circumferential protrusion groups is the same. Furthermore, the spacing between adjacent first circumferential protrusion groups, the spacing between adjacent second circumferential protrusion groups, and the spacing between adjacent third circumferential protrusion groups are all the same. This helps to ensure that the wafer has a higher flatness after adsorption.

[0051] Furthermore, the middle portion of the third boss 113 protrudes away from the central through hole 130.

[0052] Furthermore, the third interval bisects the corresponding second protrusion 112. That is, in the radial direction along the third annular region, the third interval is aligned with the middle position of the corresponding second protrusion 112. This design ensures that, given that both the second protrusion 112 and the third protrusion 113 are curved, the width of the interval between the outermost second circumferential protrusion group (far from the central through-hole 130) and the third circumferential protrusion group (closest to the central through-hole 130) is uniform and not too wide. It can even ensure that the radial width of this interval is the same as the spacing between two adjacent third circumferential protrusion groups and the spacing between two adjacent second circumferential protrusion groups. This helps to ensure a more uniform distribution of the circumferential protrusion groups and a higher flatness of the wafer after adsorption.

[0053] Furthermore, the widths of the first intervals, the second intervals, and the third intervals are all the same, and the widths of the first, second, and third intervals are all the same.

[0054] In some embodiments, the size of the chuck corresponds to a 12-inch wafer. The first annular region and the second annular region are defined with a first preset circle as the dividing line. The radius of the first preset circle is in the range of 60mm to 80mm. The second annular region and the third annular region are defined with a second preset circle as the dividing line. The radius of the second preset circle can be in the range of 90mm to 120mm.

[0055] In some embodiments, the number of first circumferential boss groups located in the first annular region is greater than the number of second circumferential boss groups located in the second annular region, and the number of second circumferential boss groups located in the second annular region is greater than the number of third circumferential boss groups located in the third annular region. In some examples, the number of first circumferential boss groups located in the first annular region may be in the range of 13 to 17, the number of second circumferential boss groups located in the second annular region may be in the range of 8 to 12, and the number of third circumferential boss groups located in the third annular region may be in the range of 7 to 11.

[0056] It is understood that the radius of the first preset circle, the radius of the second preset circle, the spacing between two adjacent circumferential boss groups, the spacing between two adjacent bosses in the same circumferential boss group, the number of the first circumferential boss groups, the number of the second circumferential boss groups, and the number of the third circumferential boss groups mentioned above are only examples. When designing the boss structure, the radius of the first preset circle, the radius of the second preset circle, the spacing between two adjacent circumferential boss groups, the spacing between two adjacent bosses in the same circumferential boss group, the number of the first circumferential boss groups, the number of the second circumferential boss groups, and the number of the third circumferential boss groups can be determined according to the actual warp state and morphology of the wafer.

[0057] Furthermore, the boss structure also includes multiple inner ring bosses 115, which are arranged circumferentially along the central through hole 130.

[0058] For a cup-shaped warped wafer, when the wafer is placed on a chuck and the chuck is not adsorbing the wafer, the central region of the wafer is concave towards the chuck, and the edge region of the wafer is warped away from the chuck relative to the central region. When the gas between the wafer and the chuck is drawn in through the central through-hole 130, a vacuum can be established from the inner ring of the circumferential boss group closest to the central through-hole 130, and the vacuum can gradually extend to the outermost sealing structure 102. Adsorption force can be formed from the central region of the wafer to the edge of the wafer. In this process, since the corresponding first intervals in each first circumferential boss group are aligned, and all the first intervals have aligned second intervals, the connected first intervals and second intervals can guide the airflow, which can make the vacuum formation speed faster. Moreover, the curved bosses are not limited to their circumference, which can reduce the leakage caused by the uneven height of the wafer surface and the corresponding area of ​​the circumference. The uniform distribution of the bosses can also ensure high flatness adsorption.

[0059] For umbrella-shaped warped wafers, since the edge of the wafer contacts the sealing structure 102 first, it is easier to establish a vacuum, and high adsorption force can be achieved. The uniform distribution of the protrusions can also ensure high flatness adsorption.

[0060] For a wavy, warped wafer, if the central region of the wafer is concave towards the chuck, the adsorption principle is similar to that for a cup-shaped, warped wafer. If the central region of the wafer is convex away from the chuck, the adsorption principle for the central region is similar to that for an umbrella-shaped, warped wafer. The vacuum in the central region of the wafer is also easier to establish, and the subsequent vacuum establishment process is similar to that for a cup-shaped, warped wafer.

[0061] Furthermore, the interior of the main body has multiple spaced-apart hollow areas.

[0062] Furthermore, the chuck is a one-piece molded structure, and it is manufactured using 3D printing technology.

[0063] In some embodiments, the cutout area can be a closed grid 103.

[0064] In some embodiments, a plurality of grids 103 are arranged in an array within the main body in a direction parallel to the bearing surface 101.

[0065] In some embodiments, the main body includes a bottom plate 121, a top plate 122, side plates 120, and a plurality of intermediate partitions 123. The top plate 122 is directly opposite to and parallel to the bottom plate 121. The surface of the top plate 122 away from the bottom plate 121 is a bearing surface 101. The side plates 120 are perpendicular to the top plate 122, and both sides of the side plates 120 are connected to the edges of the top plate 122 and the bottom plate 121, respectively. The top plate 122, the bottom plate 121, and the side plates 120 form a cavity. The intermediate partitions 123 are disposed within the cavity and are perpendicular to the top plate 122. The plurality of intermediate partitions 123 divide the cavity into a plurality of grids 103. In this way, both the weight reduction of the chuck and the rigidity of the chuck can be achieved.

[0066] This invention uses 3D printing technology to prepare a chuck. Compared with a traditional chuck of the same size, the main body has multiple spaced hollow areas inside. This design reduces the weight of the chuck by 50%, increases the natural resonant frequency by 30%, and the boss structure allows the flatness of the wafer to be improved by 50% after the chuck adsorbs the wafer. In addition, the chuck has higher rigidity, better stress release capability, and less thermal deformation.

[0067] Furthermore, the chuck provided by this invention uses a boss structure including multiple small bosses to support the wafer, which reduces the contact area between the chuck and the wafer, resulting in less particulate and metal contamination on the back of the wafer. The bosses arranged along the circumference form a circumferential boss group, and the circumference of multiple circumferential boss groups is concentric. The first and second intervals aligned radially can guide the airflow at the moment of adsorption, which can first establish a stronger adsorption force in the central region and allow the adsorption force to gradually radiate to the edge of the wafer to form adsorption on the entire wafer. The first, second, and third intervals guide the vacuum airflow, which can improve the vacuum establishment speed and reduce air leakage.

[0068] It should be understood that the various forms of processes shown above can be used to reorder, add, or delete steps. For example, the steps described in this invention disclosure can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution disclosed in this invention can be achieved, and this is not limited herein.

[0069] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A chuck, characterized in that, The utility model relates to a bearing, comprising: a main body having a load bearing surface and a central through hole extending through the main body in a thickness direction, the load bearing surface comprising a first region and a second region surrounding the first region, the first region surrounding the central through hole; a boss structure located in the first region and a sealing structure located in the second region; wherein the boss structure comprises a plurality of circumferential boss groups, each circumferential boss group corresponding to a different circumferential radius and all sharing a common center with the central through hole, each circumferential boss group comprising a plurality of curved bosses arranged along a corresponding circumference, each boss extending along the corresponding circumference; the first region comprises a first annular region surrounding the central through hole, the circumferential boss group located in the first annular region being a first circumferential boss group, the bosses in the first circumferential boss group being first bosses, a plurality of first circumferential boss groups being arranged on the first annular region, the number of first bosses in each first circumferential boss group being the same, a first interval being present between two adjacent first bosses in a first circumferential boss group, and the corresponding first intervals in each first circumferential boss group being aligned in a radial direction along the first annular region; the first region further comprises a second annular region surrounding the first annular region, the circumferential boss group located in the second annular region being a second circumferential boss group, the bosses in the second circumferential boss group being second bosses, a plurality of second circumferential boss groups being arranged on the second annular region, the number of second bosses in each second circumferential boss group being the same, a second interval being present between two adjacent second bosses in a second circumferential boss group, and the corresponding second intervals in each second circumferential boss group being aligned in a radial direction along the second annular region; the number of second bosses in the second circumferential boss group is greater than the number of first bosses in the first circumferential boss group.

2. The chuck of claim 1, wherein In the radial direction along the second annular region, part of the second intervals are aligned with the first intervals.

3. The chuck of claim 1 wherein, The number of first bosses in the first circumferential boss group is N, the number of second bosses in the second circumferential boss group is n x N, and n is an integer greater than 1.

4. The chuck of claim 3 wherein, The first annular region and the second annular region are separated by a first predetermined circle, and the boss structure further comprises N outer ring bosses, the N outer ring bosses being arranged at intervals along the first predetermined circle, and in the radial direction along the first predetermined circle, the outer ring bosses are aligned with the middle portions of the corresponding first bosses in the adjacent first circumferential boss groups.

5. The chuck of claim 1 wherein, The first region further comprises a third annular region surrounding the second annular region, a third set of circumferential bosses is located at the circumference of the third annular region, a boss in the third set of circumferential bosses is a third boss, a plurality of third sets of circumferential bosses are arranged on the third annular region, the number of the third bosses in each third set of circumferential bosses is the same, a third interval is between two adjacent third bosses in the third set of circumferential bosses, in the radial direction of the third annular region, the corresponding third intervals in each third set of circumferential bosses are aligned, and the third intervals are staggered with the second intervals; The number of the third bosses in the third set of circumferential bosses is equal to the number of the second bosses in the second set of circumferential bosses.

6. The chuck of claim 5 wherein, The middle part of the first boss protrudes towards the center through hole; the middle part of the second boss protrudes towards the center through hole; and the middle part of the third boss protrudes away from the center through hole.

7. The chuck of claim 5 wherein, The third interval bisects the corresponding second boss.

8. The chuck of claim 5 wherein, The width of each first interval is the same, the width of each second interval is the same, the width of each third interval is the same, and the width of the first interval, the width of the second interval and the width of the third interval are the same.

9. The chuck of claim 1 wherein, The boss structure further comprises a plurality of inner ring bosses arranged along the circumference of the center through hole.

10. The chuck of claim 1 wherein, The inner part of the main body part has a plurality of spaced hollow regions.

11. The chuck of claim 1 wherein, The height of the sealing structure is not less than the height of the boss structure.

12. Chuck according to any one of claims 1 to 11, characterized in that The chuck is an integral structure, and the chuck is prepared by using a 3D printing process.

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