Chuck

Abstract

The invention 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 central 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 central through hole; the boss structure is positioned in the first area; the sealing structure is positioned in the second area; wherein the boss structure comprises a plurality of circumferential boss groups, the circumferential radiuses corresponding to the circumferential boss groups are different, the circumferential boss groups and the central through hole are concentric, each circumferential boss group comprises a plurality of curved bosses which are arranged at intervals along the corresponding circumference, and each boss extends along the corresponding circumference. According to the chuck provided by the invention, the wafer can be adsorbed with higher adsorption force, and the wafer is ensured to have higher flatness.

Description

Technical Field

[0001] The invention belongs to the technical field of semiconductor detection, and in particular relates to a chuck. Background Art

[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 calibrate the lithography machine process. During the measurement process, the wafer needs to be placed under the optical detection system, and the chuck is used to drive the wafer to perform a high-acceleration acceleration or deceleration movement. After the wafer is moved into position, the wafer needs to quickly reach a nanometer-level position stability state. After analysis, it was found that for processes below the 28nm node, higher measurement speeds and measurement accuracy are required. Therefore, the corresponding platform that drives the wafer movement requires higher acceleration and higher position stability. At present, it is at least required that the acceleration of the platform that drives the wafer movement is not less than 2g (g is the acceleration of gravity), and the in-position stability of the wafer when static is less than 1nm.

[0003] However, due to the rise of advanced packaging in recent years, the advanced packaging process has caused the wafer warpage to become larger and the morphology to become more complex. For the chuck, it needs to be compatible with wafers with larger warpage. At the same time, during the overlay measurement process, if the flatness of the wafer surface after adsorption is poor, it will also have a negative impact on the measurement accuracy. Therefore, it is urgent to design a chuck that can be compatible with large warpage, high flatness after adsorption, adapt to high acceleration movement and have high in-place stability. Summary of the Invention

[0004] In view of this, the present invention aims to provide a chuck that is conducive to achieving higher adsorption force on the wafer and ensuring that the wafer has higher flatness.

[0005] To achieve the above object, the technical solution created by the present invention is implemented as follows: The present invention provides a chuck, comprising: a main body, the main body having a bearing surface and a central through hole passing through the main body in the thickness direction, the bearing surface comprising a first area and a second area surrounding the first area, the first area surrounding the central through hole; a boss structure located in the first area and a sealing structure located in the second area; wherein the boss structure comprises a plurality of circumferential boss groups, the circumferential radii corresponding to the circumferential boss groups being different and all being concentric with the central through hole, each circumferential boss group comprising a plurality of curved bosses arranged at intervals along the corresponding circumference, and each boss extending along the corresponding circumference.

[0006] Furthermore, the first area includes a first annular area surrounding the central through hole, the circumferential boss group located in the first annular area is a first circumferential boss group, the boss in the first circumferential boss group is a first boss, and multiple first circumferential boss groups are arranged on the first annular area. The number of first bosses in each first circumferential boss group is the same, and there is a first interval between two adjacent first bosses in the first circumferential boss group. In the radial direction along the first annular area, the corresponding first intervals in each first circumferential boss group are aligned.

[0007] Furthermore, the first area also includes a second annular area surrounding the first annular area, the circumferential boss group located in the second annular area is the second circumferential boss group, the bosses in the second circumferential boss group are second bosses, and multiple second circumferential boss groups are arranged on the second annular area. The number of second bosses in each second circumferential boss group is the same, and there is a second interval between two adjacent second bosses in the second circumferential boss group. In the radial direction along the second annular area, 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.

[0008] Further, in the radial direction along the second annular region, a portion of the second interval is aligned with the first interval.

[0009] Furthermore, the number of first bosses in the first circumferential boss group is N, and the number of second bosses in the second circumferential boss group is n×N, where n is an integer greater than 1.

[0010] Furthermore, the first annular area and the second annular area are divided by the first preset circle, and the boss structure also includes N outer ring bosses, which 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.

[0011] Furthermore, the first area also includes a third annular area surrounding the second annular area, the circumferential boss group located in the third annular area is the third circumferential boss group, the boss in the third circumferential boss group is the third boss, and multiple third circumferential boss groups are arranged on the third annular area. The number of third bosses in each third circumferential boss group is the same, and there is a third interval between two adjacent third bosses in the third circumferential boss group. In the radial direction along the third annular area, the corresponding third intervals in each third circumferential boss group are aligned, and the third interval is staggered with the second interval; 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.

[0012] Furthermore, the middle portion of the first boss protrudes toward the center through hole; the middle portion of the second boss protrudes toward the center through hole; and the middle portion of the third boss protrudes in a direction away from the center through hole.

[0013] Furthermore, the third interval divides the corresponding second boss into two equal parts.

[0014] Furthermore, the widths of the first intervals are the same, the widths of the second intervals are the same, the widths of the third intervals are the same, and the widths of the first intervals, the second intervals, and the third intervals are the same.

[0015] Furthermore, the boss structure also includes a plurality of inner ring bosses, and the plurality of inner ring bosses are arranged along the circumference of the central through hole.

[0016] Furthermore, the interior of the main body has a plurality of hollow areas arranged at intervals.

[0017] Furthermore, the height of the sealing structure is not less than the height of the boss structure.

[0018] Furthermore, the chuck is an integrally formed structure and is prepared using a 3D printing process.

[0019] Compared with the prior art, the invention can achieve the following beneficial effects: the chuck provided by the present invention includes a main body, and a plurality of grids arranged at intervals are designed inside the main body, which not only helps to reduce the weight of the chuck but also ensures that the chuck has a high structural strength. The bearing surface of the main body is provided with a sealing structure and a boss structure located on the inner circle of the sealing structure. The boss structure includes a plurality of circumferential boss groups, each of which includes a plurality of 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 through the central through hole, it can be achieved from the circumferential boss closest to the central through hole. A vacuum is established in the inner circle of the stage group, and the vacuum is gradually diffused to the sealing structure of the outermost circle, forming an adsorption force from the center area of ​​the wafer to the edge of the wafer, thereby making the vacuum formation faster, reducing air leakage, and increasing the adsorption force. The curved bosses make the bosses not only limited to the circumference of their arrangement, which can reduce the air leakage caused by the height inconsistency between the wafer surface and the area corresponding to the circumference. In this way, multiple circumferential boss groups work together to achieve high adsorption force and high flatness adsorption for wafers with bowl-shaped warping, umbrella-shaped warping, and wavy warping, which is beneficial to improving the measurement precision and accuracy of overlay measurement. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The accompanying drawings, which constitute part of the present invention, are intended to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are intended to explain the present invention and do not constitute an undue limitation of the present invention. In the accompanying drawings: Figure 1 A top view of a chuck according to an embodiment of the present invention; Figure 2A schematic diagram of a portion of the structure of the chuck according to an embodiment of the present invention. DETAILED DESCRIPTION

[0021] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is 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 only used to explain the present invention and do not constitute a limitation of the present invention.

[0022] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other.

[0023] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, features defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0024] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "installed," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium; and they can refer to internal connections between two components. Those skilled in the art can understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0025] The present invention will be described in detail below with reference to the accompanying drawings and in combination with embodiments.

[0026] refer to Figures 1 to 2The present invention provides a chuck, comprising: a main body, the main body having a bearing surface 101 and a central through hole 130 running through the main body in the thickness direction, the bearing surface 101 comprising a first area and a second area surrounding the first area, the first area surrounding the central through hole 130; a boss structure located in the first area and a sealing structure 102 located in the second area; wherein the boss structure comprises a plurality of circumferential boss groups, the circumferential radii corresponding to the circumferential boss groups being different and all being concentric with the central through hole 130, each circumferential boss group comprising a plurality of curved bosses spaced apart along a corresponding circumference, and each boss extending along a corresponding circumference.

[0027] In some embodiments, the height of the sealing structure 102 is not less than the height of the boss structure.

[0028] 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 , or in other words, is concentric with the circumference corresponding to each circumferential boss group.

[0029] It should be noted that the chuck is used to adsorb the wafer and drive the wafer to move. The boss structure is located in the inner circle of the sealing structure 102, and the boss structure and the sealing structure 102 are used to support the wafer on the side away from the carrying surface 101. 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 carrying surface 101, thereby forming negative pressure adsorption on the wafer, and the boss structure is used to support the wafer.

[0030] In some embodiments, the central through hole 130 passes through the main body along the thickness direction of the main body.

[0031] In some embodiments, the bosses in the same circumferential boss group have the same shape and size.

[0032] In some embodiments, a plurality of circumferential boss groups are evenly distributed between the central through hole 130 and the sealing structure 102 .

[0033] In some embodiments, the spacing between two adjacent circumferential boss groups is in the range of 2.8 mm to 3 mm, and in the same circumferential boss group, the spacing between two adjacent bosses is in the range of 2.3 mm to 2.7 mm.

[0034] In some embodiments, the cross-section of the boss along its thickness direction may be trapezoidal, so as to avoid the boss edge being too sharp, thereby reducing scratches on the wafer to a certain extent.

[0035] In some embodiments, the main body also has a plurality of ejector pin holes 131 and a plurality of mounting holes 132. Both the ejector pin holes 131 and the mounting holes 132 pass through the main body along the thickness direction of the main body. The ejector pin hole 131 is used to set a liftable ejector pin. The ejector pin is used to lift the wafer to facilitate the robot to pick up and place the wafer. After the robot places the wafer on the chuck, the ejector pin descends so that the wafer falls on the chuck. The mounting hole 132 is used to set a mounting part. The mounting part is used to mount the chuck on the driving mechanism. The driving 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.

[0036] In a specific embodiment, the main body has three ejector holes 131 and three mounting holes 132. The line connecting the centers of the three ejector holes 131 forms a first equilateral triangle, and the center of the first equilateral triangle 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, and the center of the second equilateral triangle 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.

[0037] Furthermore, the first area includes a first annular area surrounding the central through hole 130, the circumferential boss group located in the first annular area is the first circumferential boss group, the boss in the first circumferential boss group is the first boss 111, and multiple first circumferential boss groups are arranged on the first annular area. The number of first bosses 111 in each first circumferential boss group is the same, and 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 area, the corresponding first intervals in each first circumferential boss group are aligned.

[0038] In some examples, the number of first bosses 111 in each first circumferential boss group is twelve.

[0039] Furthermore, a middle portion of the first boss 111 protrudes toward the central through hole 130 .

[0040] Furthermore, the first area also includes a second annular area surrounding the first annular area, the circumferential boss group located in the second annular area is the second circumferential boss group, the boss in the second circumferential boss group is the second boss 112, and multiple second circumferential boss groups are arranged on the second annular area. The number of second bosses 112 in each second circumferential boss group is the same, and 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 area, 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.

[0041] Furthermore, a middle portion of the second boss 112 protrudes toward the central through hole 130 .

[0042] Furthermore, along the radial direction of the second annular region, some of the second intervals are aligned with the first intervals. This can guide the radial airflow and increase the speed at which the vacuum diffuses outward from the central through hole 130, thereby reducing air leakage and significantly enhancing the ability to adsorb wafers with large wave-shaped warping.

[0043] In some embodiments, in a radial direction along the second annular region, all of the first spacings have aligned second spacings.

[0044] Furthermore, the number of the first bosses 111 in the first circumferential boss group is N, and the number of the second bosses 112 in the second circumferential boss group is n×N, where n is an integer greater than 1. In some examples, n is 2.

[0045] Furthermore, the first annular area and the second annular area are separated by a first predetermined circle. The boss structure further includes N outer ring bosses 114, which are spaced apart along the first predetermined circle. In the radial direction of the first predetermined circle, outer ring bosses 114 align with the middle portions of corresponding first bosses 111 in the adjacent first circumferential boss group. Outer ring bosses 114 fill the large gap between first bosses 111 and second bosses 112, preventing excessive spacing between bosses from negatively impacting the flatness of the adsorbed wafer.

[0046] Furthermore, the first area also includes a third annular area surrounding the second annular area, the circumferential boss group located in the third annular area is the third circumferential boss group, the boss in the third circumferential boss group is the third boss 113, and multiple third circumferential boss groups are arranged on the third annular area. The number of third bosses 113 in each third circumferential boss group is the same, and there is a third interval between two adjacent third bosses 113 in the third circumferential boss group. In the radial direction of the third annular area, the corresponding third intervals in each third circumferential boss group are aligned, and the third interval is staggered with the second interval; 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.

[0047] In some embodiments, in the first annular region, the spacing between any two adjacent first circular boss groups is the same, in the second annular region, the spacing between any two adjacent second circumferential boss groups is the same, and in the third annular region, the spacing between any two adjacent third circumferential boss groups is the same, and the spacing between two adjacent first circumferential boss groups, the spacing between two adjacent second circumferential boss groups, and the spacing between two adjacent third circumferential boss groups are all the same. This is beneficial to ensure that the wafer has higher flatness after adsorption.

[0048] Furthermore, a middle portion of the third boss 113 protrudes in a direction away from the central through hole 130 .

[0049] Furthermore, the third interval bisects the corresponding second boss 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 boss 112. With this design, under the premise that the second boss 112 is curved and the third boss 113 is also curved, the width of the interval area between the second circumferential boss group located on the outermost circle away from the central through hole 130 and the third circumferential boss group closest to the central through hole 130 is uniform and not too wide. It can even be ensured that the width of the interval area in the radial direction is the same as the spacing between two adjacent third circumferential boss groups and the spacing between two adjacent second circumferential boss groups. This is conducive to ensuring a more uniform distribution of the circumferential boss groups and ensuring that the wafer has a higher flatness after adsorption.

[0050] Furthermore, the widths of the first intervals are the same, the widths of the second intervals are the same, the widths of the third intervals are the same, and the widths of the first intervals, the second intervals, and the third intervals are the same.

[0051] In some embodiments, the size of the chuck corresponds to a 12-inch wafer, and the first annular area and the second annular area are defined with the first preset circle as the dividing line, and the radius of the first preset circle is in the range of 60mm~80mm. The second annular area and the third annular area are defined with the second preset circle as the dividing line, and the radius of the second preset circle can be in the range of 90mm~120mm.

[0052] In some embodiments, the number of first circumferential boss groups in the first annular region is greater than the number of second circumferential boss groups in the second annular region, and the number of second circumferential boss groups in the second annular region is greater than the number of third circumferential boss groups in the third annular region. In some examples, the number of first circumferential boss groups in the first annular region may be in the range of 13 to 17, the number of second circumferential boss groups in the second annular region may be in the range of 8 to 12, and the number of third circumferential boss groups in the third annular region may be in the range of 7 to 11.

[0053] It can be 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 first circumferential boss groups, the number of second circumferential boss groups and the number of third circumferential boss groups are merely 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 first circumferential boss groups, the number of second circumferential boss groups and the number of third circumferential boss groups can be determined according to the actual warping state and morphology of the wafer.

[0054] Furthermore, the boss structure further includes a plurality of inner ring bosses 115 , and the plurality of inner ring bosses 115 are arranged along the circumference of the central through hole 130 .

[0055] For a bowl-shaped warped wafer, when the wafer is placed on the chuck and the chuck does not adsorb the wafer, the center area of ​​the wafer is concave toward the chuck, and the edge area of ​​the wafer is warped away from the chuck relative to the center area. When the gas between the wafer and the chuck is sucked through the center through hole 130, a vacuum can be established from the inner circle of the circumferential boss group closest to the center through hole 130, and the vacuum is gradually extended to the outermost sealing structure 102, and an adsorption force can be gradually formed from the center area of ​​the wafer toward 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. The curved boss makes the boss not only limited to the circumference of its arrangement, which can reduce the leakage caused by the height inconsistency between the wafer surface and the area corresponding to the circumference. The uniform distribution of the boss can also ensure high-flatness adsorption.

[0056] For wafers with umbrella-shaped warping, since the edge of the wafer contacts the sealing structure 102 first, vacuum is easier to establish and adsorption with high adsorption force can be achieved. The uniform distribution of the bosses can also ensure adsorption with high flatness.

[0057] For a wafer with wavy warpage, if the center area of ​​the wafer is concave toward the chuck, the principle of adsorption is similar to the principle of adsorption for a wafer with bowl-shaped warpage. If the center area of ​​the wafer is convex away from the chuck, the principle of adsorption for the center area of ​​the wafer is similar to the principle of adsorption for a wafer with umbrella-shaped warpage. It is also easier to establish vacuum in the center area of ​​the wafer, and the subsequent vacuum establishment process is similar to the principle of adsorption for a wafer with bowl-shaped warpage.

[0058] Furthermore, the interior of the main body has a plurality of hollow areas arranged at intervals.

[0059] Furthermore, the chuck is an integrally formed structure and is prepared using a 3D printing process.

[0060] In some embodiments, the hollowed-out area may be a closed grid 103 .

[0061] In some embodiments, the plurality of grids 103 are arranged in an array in the main body along a direction parallel to the carrying surface 101 .

[0062] 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 arranged opposite and parallel to the bottom plate 121. The surface of the top plate 122 away from the bottom plate 121 is the bearing surface 101. The side plates 120 are perpendicular to the top plate 122, and the two sides of the side plates 120 are connected to the edges of the top plate 122 and the edges of 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 arranged in the cavity. The intermediate partitions 123 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, the chuck can be made lightweight while improving its rigidity.

[0063] The present invention uses a 3D printing process to prepare a chuck. Compared with traditional chucks with the same external dimensions, the interior of the main body has multiple hollow areas arranged at intervals. This design reduces the weight of the chuck by 50% and increases the natural resonant frequency by 30%. The design of the boss structure allows the flatness of the wafer to be increased by 50% after the chuck adsorbs the wafer. The chuck also has higher rigidity, better stress release capability and smaller thermal deformation.

[0064] The chuck provided by the present invention uses a boss structure including multiple small bosses to support the wafer, which reduces the contact area between the chuck and the wafer, and reduces particle contamination and metal contamination on the back of the wafer. The bosses arranged along the circumference constitute a circumferential boss group, and the circumferences where the multiple circumferential boss groups are located are concentric. The first interval and the second interval aligned in the radial direction can guide the airflow at the moment of starting adsorption, and can first establish a stronger adsorption force in the central area, and the adsorption force can gradually radiate to the edge of the wafer to form adsorption of the entire wafer. The first interval, the second interval and the third interval guide the vacuum airflow, which can increase the vacuum establishment speed and reduce air leakage.

[0065] It should be understood that the various forms of the processes shown above can be used to reorder, add, or delete steps. For example, the steps described in the present disclosure can be performed in parallel, sequentially, or in a different order, as long as the desired results of the technical solutions disclosed in the present disclosure can be achieved. This is not limited herein.

[0066] The above specific embodiments do not limit the scope of protection of the present invention. Those skilled in the art will appreciate that various modifications, combinations, sub-combinations, and substitutions may be made based on design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention are intended to be included within the scope of protection of the present invention.

Claims

1. A chuck, characterized in that: include: a main body portion, the main body portion having a bearing surface and a central through hole extending through the main body portion in a 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; Among them, the boss structure includes multiple circumferential boss groups, each circumferential boss group corresponds to a different circumferential radius and is concentric with the central through hole, each circumferential boss group includes multiple curved bosses arranged at intervals along the corresponding circumference, and each boss extends along the corresponding circumference.

2. The chuck according to claim 1, wherein: The first area includes a first annular area surrounding the central through hole, the circumferential boss group located in the first annular area is a first circumferential boss group, the bosses in the first circumferential boss group are first bosses, and multiple first circumferential boss groups are arranged on the first annular area. The number of first bosses in each of the first circumferential boss groups is the same, and there is a first interval between two adjacent first bosses in the first circumferential boss group. In the radial direction along the first annular area, the corresponding first intervals in each of the first circumferential boss groups are aligned.

3. The chuck according to claim 2, wherein: The first region further 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, the bosses in the second circumferential boss group are second bosses, a plurality of second circumferential boss groups are provided on the second annular region, the number of second bosses in each of the second circumferential boss groups is the same, a second interval is formed between adjacent two second bosses in the second circumferential boss group, and in the radial direction along the second annular region, the corresponding second intervals in each of the second circumferential boss groups 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.

4. The chuck according to claim 3, wherein: In a radial direction along the second annular region, a portion of the second interval is aligned with the first interval.

5. The chuck according to claim 3, wherein: The number of first bosses in the first circumferential boss group is N, and the number of second bosses in the second circumferential boss group is n×N, where n is an integer greater than 1.

6. The chuck according to claim 5, wherein: The first annular area and the second annular area are divided by a first preset circle. The boss structure also includes N outer ring bosses, which 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 parts of the corresponding first bosses in the adjacent first circumferential boss group.

7. The chuck according to claim 3, wherein: The first area further includes a third annular area surrounding the second annular area, the circumferential boss group located in the third annular area is a third circumferential boss group, the bosses in the third circumferential boss group are third bosses, a plurality of third circumferential boss groups are provided on the third annular area, the number of the third bosses in each of the third circumferential boss groups is the same, a third interval is formed between two adjacent third bosses in the third circumferential boss group, and in the radial direction of the third annular area, the corresponding third intervals in each of the third circumferential boss groups are aligned, and the third intervals are staggered with the second intervals; The number of the third bosses in the third circumferential boss group is equal to the number of the second bosses in the second circumferential boss group.

8. The chuck according to claim 7, wherein: The middle portion of the first boss protrudes toward the central through hole; the middle portion of the second boss protrudes toward the central through hole; and the middle portion of the third boss protrudes away from the central through hole.

9. The chuck according to claim 7, wherein: The third interval bisects the corresponding second boss.

10. The chuck according to claim 7, wherein: The widths of the first intervals are the same, the widths of the second intervals are the same, the widths of the third intervals are the same, and the widths of the first intervals, the second intervals, and the third intervals are the same.

11. The chuck according to claim 1, wherein: The boss structure further includes a plurality of inner ring bosses, which are arranged along the circumference of the central through hole.

12. The chuck according to claim 1, wherein: The interior of the main body has a plurality of hollow areas arranged at intervals.

13. The chuck according to claim 1, wherein: The height of the sealing structure is not less than the height of the boss structure.

14. The chuck according to any one of claims 1 to 13, characterized in that The chuck is an integrally formed structure and is prepared using a 3D printing process.

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