CN112539773B

CN112539773B - Sucking disc and motion system

Info

Publication number: CN112539773B
Application number: CN201910900879.8A
Authority: CN
Inventors: 管博然
Original assignee: Shanghai Micro Electronics Equipment Co Ltd
Current assignee: Shanghai Micro Electronics Equipment Co Ltd
Priority date: 2019-09-23
Filing date: 2019-09-23
Publication date: 2022-02-08
Anticipated expiration: 2039-09-23
Also published as: CN112539773A

Abstract

The invention provides a sucking disc and a motion system, wherein the sucking disc comprises more than two vacuum gas circuits and a sheet fork groove, each vacuum gas circuit comprises a gas circuit interface, and all the gas circuit interfaces are uniformly distributed by taking the circle center of the sucking disc as the center and are intensively arranged in a first area with the circle center of the sucking disc as the center and the radius of r; the piece fork groove is arranged on the top surface along the diameter direction of the sucker, and all the vacuum air paths are kept away from the piece fork groove. So dispose for the gas circuit interface is concentrated and is set up at the centre of a circle periphery, guarantees that the convenient trachea of switching on the vacuum source of gas circuit interface, simplifies the structure of trachea junction, and simple structure, the processing of the piece fork recess of setting are convenient and the processing cost is low, avoid using the complicated sliding ring structure of structure and the very high pin structure of cost, have guaranteed better adsorption effect simultaneously.

Description

Sucking disc and motion system

Technical Field

The invention relates to the technical field of silicon wafer detection, in particular to a sucker and a motion system.

Background

With the rapid development of the semiconductor industry, the technical field of silicon wafer detection is also continuously subject to technical innovation. A carrier for bearing a silicon wafer in the silicon wafer detection instrument is called a wafer bearing table, the wafer bearing table comprises a sucker for sucking and fixing the silicon wafer, the sucker is positioned and adsorbed on the upper surface of a base of the wafer bearing table, and the silicon wafer can move or rotate along with the wafer bearing table in the detection process. Generally, the adsorption of the silicon wafer mainly comprises electrostatic adsorption and vacuum adsorption, the electrostatic adsorption process is complex, the cost is high, the vacuum adsorption utilizes vacuum to carry out contact adsorption, the realization is easy, the cost is low, and the vacuum adsorption mode is commonly used for adsorbing the silicon wafer at present.

In the prior art, a suction cup usually adopts a slip ring structure to adsorb a silicon wafer, gas path interfaces at the bottom of the suction cup are distributed and dispersed, and the slip ring structure is very complex and has high cost; correspondingly, the design of the pin structure is adopted in the sucker, the design process requirement of the structure is high, and the cost is high.

Disclosure of Invention

The invention aims to provide a sucker and a wafer bearing platform, and aims to solve the problems of complex structure and high cost of the conventional sucker.

In order to solve the above technical problems, the present invention provides a suction cup: the sucking disc has the top surface that is used for bearing a basement to and the bottom surface that is used for being connected with the wafer stage, the sucking disc includes: more than two vacuum gas circuits arranged between the top surface and the bottom surface; each vacuum gas circuit comprises a gas circuit interface and a plurality of gas suction ports arranged on the top surface, all the gas circuit interfaces are uniformly distributed by taking the circle center of the sucking disc as the center, and all the gas circuit interfaces are intensively arranged in a first area which takes the circle center of the sucking disc as the center and has the radius of r; the sheet fork groove is arranged on the top surface along the diameter direction of the sucker and is used for being matched with a sheet fork; each vacuum gas circuit is used for being matched with a substrate with one diameter, and all the vacuum gas circuits are arranged in a manner of avoiding the grooves of the sheet forks.

Optionally, the suction cup includes two vacuum gas paths, which are a first vacuum gas path and a second vacuum gas path, respectively, the first vacuum gas path is used for adapting to the substrate with the first diameter, the second vacuum gas path is used for adapting to the substrate with the second diameter, and the first diameter is smaller than the second diameter.

Optionally, the first vacuum air passage includes two first air passages, an arrangement direction of one of the first air passages is the same as a setting direction of the sheet fork groove, and the air passage interface is disposed on one of the first air passages.

Optionally, the second vacuum air path includes three second air paths arranged at intervals in sequence along the first direction, a third air path arranged along the second direction, and two fourth air paths arranged along the third direction, wherein the third air path penetrates through the three second air paths, the two fourth air paths are respectively connected with two second air paths located at two sides of the three second air paths arranged in sequence, and the air path interface is arranged on the second air path located in the middle of the three second air paths arranged in sequence.

Optionally, the suction cup further comprises a side wall perpendicular to the top surface, and the side wall is arranged along the periphery of the suction cup and the periphery of the sheet fork groove; the first vacuum air path and the second vacuum air path are both parallel to the top surface, and plugs are arranged at intersection points of the first vacuum air path and the second vacuum air path and the side wall.

Optionally, the top surface includes a plurality of separation grooves, and the separation grooves are disposed between regions of the top surface corresponding to the regions for carrying substrates with different diameters.

Optionally, the bottom surface includes a support structure including a plurality of ribs diverging outwardly from a circle center.

Optionally, the bottom surface further comprises a weight-reducing structure, and the weight-reducing structure comprises a step descending from the center of the sucker to the edge of the sucker.

Optionally, a positioning platform is further arranged at the center of the bottom surface, and the positioning platform is used for being connected with the wafer bearing table in a positioning mode.

In order to solve the technical problem, the invention further provides a motion platform which comprises any one of the suckers, a wafer bearing table, a vacuum source and an air pipe, wherein the wafer bearing table is connected with the bottom surface of the sucker, and the vacuum source is connected with an air passage interface of the sucker through the air pipe.

In the sucking disc and the movement system provided by the invention, the sucking disc comprises more than two vacuum gas circuits and a sheet fork groove, each vacuum gas circuit comprises a gas circuit interface, and all the gas circuit interfaces are uniformly distributed by taking the circle center of the sucking disc as the center and are intensively arranged in a first area with the circle center of the sucking disc as the center and the radius of r; the piece fork groove is arranged on the top surface along the diameter direction of the sucker, and all the vacuum air paths are kept away from the piece fork groove. So dispose for the gas circuit interface is concentrated and is set up at the centre of a circle periphery, guarantees that the convenient trachea of switching on the vacuum source of gas circuit interface, simplifies the structure of trachea junction, makes in its working process safer, and piece fork groove structure is simple, processing is convenient and the processing cost is low, avoids using the slip ring structure and the very high pin structure of cost that the structure is complicated, has guaranteed better adsorption effect simultaneously.

Drawings

Those skilled in the art will appreciate that the drawings are provided for a better understanding of the invention and do not constitute any limitation on the scope of the invention. Wherein:

FIG. 1 is a schematic view of a chuck according to an embodiment of the present invention;

FIG. 2 is a cross-sectional view of the suction cup shown in FIG. 1 taken along the X-Y plane;

fig. 3 is a schematic view of another angle (back) of the chuck shown in fig. 1.

In the drawings: 10-a top surface; 11-separation grooves; 20-a bottom surface; 30-a side wall; 31-plug; 110-gas path interface; 120-suction port; 130-a first vacuum gas circuit; 131-a first air passage; 140-a second vacuum gas circuit; 141-a second airway; 142-a third airway; 143-fourth airway; 200-piece fork grooves; 300-vacuum adsorption area; 400-a support structure; 410-ribs; 500-a weight reduction structure; 510-step; 600-positioning the platform.

Detailed Description

To further clarify the objects, advantages and features of the present invention, a more particular description of the invention will be rendered by reference to specific embodiments thereof which are illustrated in the appended drawings. It is to be noted that the drawings are in greatly simplified form and are not to scale, but are merely intended to facilitate and clarify the explanation of the embodiments of the present invention. Further, the structures illustrated in the drawings are often part of actual structures. In particular, the drawings may have different emphasis points and may sometimes be scaled differently.

As used in this specification, the singular forms "a," "an," and "the" include plural referents unless the content clearly dictates otherwise. As used in this specification, the term "or" is generally employed in its sense including "and/or" unless the content clearly dictates otherwise.

The core idea of the invention is to provide a sucker and a motion platform, so as to solve the problems of complex structure and high cost of the existing sucker.

In the suction cup and the motion platform provided by the invention, the suction cup comprises: the vacuum air channels are arranged between the top surface and the bottom surface; each vacuum gas circuit comprises a gas circuit interface and a plurality of gas suction ports arranged on the top surface, all the gas circuit interfaces are uniformly distributed by taking the circle center of the sucking disc as the center, and all the gas circuit interfaces are intensively arranged in a first area which takes the circle center of the sucking disc as the center and has the radius of r; the sheet fork groove is arranged on the top surface along the diameter direction of the sucker and is used for being matched with a sheet fork; each vacuum gas circuit is used for being matched with a substrate with one diameter, and all the vacuum gas circuits are arranged in a manner of avoiding the grooves of the sheet forks. So dispose for the gas circuit interface is concentrated and is set up at the centre of a circle periphery, guarantees that the convenient trachea of switching on the vacuum source of gas circuit interface, simplifies the structure of trachea junction, and simple structure, the processing of the piece fork recess of setting are convenient and the processing cost is low, avoid using the complicated sliding ring structure of structure and the very high pin structure of cost, have guaranteed better adsorption effect simultaneously.

The following description refers to the accompanying drawings.

Referring to fig. 1 to 3, in which fig. 1 is a schematic view illustrating a chuck according to an embodiment of the present invention; FIG. 2 is a cross-sectional view of the suction cup shown in FIG. 1 taken along the X-Y plane; fig. 3 is a schematic view of another angle (back) of the chuck shown in fig. 1.

As shown in FIG. 1, the present invention provides a chuck having a top surface 10 for supporting a substrate (e.g., a silicon wafer) and a bottom surface 20 for connecting to a stage, the chuck comprising: more than two vacuum gas circuits and a piece fork groove 200, wherein the two vacuum gas circuits are arranged between the top surface 10 and the bottom surface 20; each vacuum gas path comprises a gas path interface 110 and a plurality of gas suction ports 120 arranged on the top surface 10, all the gas path interfaces 110 are uniformly distributed by taking the circle center of the sucker as the center, and all the gas path interfaces 110 are intensively arranged in a first area with the circle center of the sucker as the center and the radius of r, preferably, all the gas path interfaces are uniformly distributed by taking the circle center of the sucker as the center; the sheet fork groove 200 is arranged on the top surface 10 along the diameter direction of the sucker and is used for matching with a sheet fork; each vacuum gas path is used for being matched with a substrate with one diameter, and all the vacuum gas paths are arranged to avoid the sheet fork groove 200. In an exemplary embodiment, as shown in fig. 1-2, the chuck includes two vacuum circuits, a first vacuum circuit 130 and a second vacuum circuit 140. Each vacuum air path is independent and does not interfere with each other, each vacuum air path comprises an air path interface 110, the air path interface 110 is used for being connected with an external air pipe so as to be communicated with a vacuum source, each vacuum air path comprises a plurality of air suction ports 120 arranged on the top surface 10, after a substrate is placed on the top surface 10, the air path interface 110 is under the negative pressure action of the vacuum source through the air pipe, and the parts of the vacuum adsorption area 300 on the top surface 10 are vacuumized through the air suction ports 120 of the vacuum air paths, so that the substrate is firmly and stably adsorbed on the sucking disc. The vacuum air path can also be three or four, and is not limited to two vacuum air paths. All the gas path interfaces 110 are intensively arranged in an area with a radius R, preferably, the ratio of the radius R to the radius R of the sucker is not more than two fifths, each vacuum gas path has only one gas path interface 110, and the gas path interface of the first vacuum gas path 130 and the gas path interface of the second vacuum gas path 140 are centrosymmetric along the center of the circle of the sucker, in other embodiments, each vacuum gas path may also be a plurality of gas path interfaces 110, the distribution of the gas path interfaces 110 is not limited to be centrosymmetric, and the position slightly deviating from the centrosymmetric position also belongs to the range of uniform distribution. The shape of the blade fork groove 200 is an axisymmetrical structure, and specifically, taking fig. 2 as an example, the shape of the blade fork groove 200 is a U-shaped structure with an opening facing right. The gas circuit interface 110 is intensively arranged at the periphery of the circle center to ensure that the gas circuit interface 110 is conveniently communicated with the gas pipe of a vacuum gas source, when the work is started, if the sucker needs to rotate, the sucker rotates to drive the gas pipe to rotate together, and after the work is finished, the sucker resets and the gas pipe resets. Every vacuum gas circuit includes that a gas circuit interface 110 has simplified the quantity of gas circuit interface 110, and the piece fork recess 200 simple structure, the processing of setting is convenient and the processing cost is low, avoids using the pin structure that the structure is complicated and with high costs, has guaranteed better adsorption effect simultaneously.

Preferably, as shown in fig. 2, the first vacuum gas path 130 and the second vacuum gas path 140 are independent from each other, and the diameter of the substrate adapted to the first vacuum gas path 130 is smaller than the diameter of the substrate adapted to the second vacuum gas path 140, specifically, after the substrate with the first diameter is placed in the chuck, the gas path interface 110 of the first vacuum gas path 130 vacuumizes the vacuum adsorption area 300 where the substrate with the first diameter is located under the negative pressure, so as to adsorb the substrate with the first diameter on the chuck; when a substrate with a second diameter is placed in the chuck, the gas path interfaces 110 of the first vacuum gas path 130 and the second vacuum gas path 140 are both vacuumized under the action of negative pressure, and the vacuum adsorption area 300 where the substrate with the second diameter is located adsorbs the substrate with the second diameter on the chuck under the action of negative pressure. Preferably, the first diameter is 8 inches and the second diameter is 12 inches.

As shown in fig. 2, preferably, the first vacuum air path 130 includes two first air paths 131, wherein an arrangement direction of one of the first air paths 131 is the same as an arrangement direction of the blade fork groove 200 (e.g., a Y direction in fig. 2), and the air path interface 110 is disposed on one of the first air paths 131. Preferably, the blade fork groove is provided with an axisymmetric structure, the direction of one first air passage 131 is parallel to the symmetry axis of the blade fork groove 200, the other first air passage 131 passes through the center of a circle, and more preferably, the two first air passages 131 are perpendicular to each other. Certainly two first air flue 131 can have the arrangement of certain contained angle according to actual conditions, for example 30 or 60, two first air flue 131 all avoids piece fork recess 200 to set up, it does to avoid piece fork recess 200 the part of piece fork recess 200 does not set up vacuum channel, and the part that is provided with vacuum channel breaks vacuum channel when meetting the piece fork recess.

Preferably, the second vacuum air path 140 includes three second air paths 141 sequentially arranged along the first direction at intervals, a third air path 142 arranged along the second direction, and two fourth air paths 143 arranged along the third direction, wherein the third air path 142 penetrates through the three second air paths 141, the two fourth air paths 143 are respectively connected with two second air paths 141 located at two sides of the three sequentially arranged second air paths 141, and the air path interface 110 is disposed on the middle second air path 141 of the three sequentially arranged second air paths 141. In an exemplary embodiment, as shown in fig. 2, three second air passages 141 are sequentially arranged at intervals to ensure that the passages are uniformly distributed as much as possible in the presence of the sheet fork grooves 200, the direction of the middle second air passage 141 points to the center of a circle, and the second air passages 141 on two sides are distributed on two sides of the middle second air passage 141 in parallel and at equal intervals. Of course, the second air passages 141 of the second vacuum air passage 140 may not point to the center of the circle, and may be parallel to the symmetry axis of the sheet fork groove 200, the second air passages 141 on both sides of the second vacuum air passage 140 may also be arranged at an included angle of 30 ° or 60 ° with the symmetry axis, or at any angle, the two air passages of the second air passage 141 may also be arranged non-parallel, or at an unequal distance, or the second air passages 141 on both sides may be symmetrically arranged with the middle second air passage 141 as the symmetry axis, which may be the same as the above schemes. The third air passage 142 connects the three second air passages 141 together, and the third air passage 142 is preferably arranged perpendicular to the middle second air passage 141, although the third air passage 142 may not be arranged perpendicular. The second vacuum air path 140 further includes two fourth air paths 143, the two fourth air paths 143 are respectively vertically communicated with the second air paths 141 on the two sides and are arranged toward the outer side of the circle center, of course, the fourth air paths 143 on the two sides may also be symmetrically arranged, and the fourth air paths 143 may not be perpendicular to the second air paths 141 on the two sides, or may not be arranged toward the outer side of the circle center. The air path interface 110 is disposed at an end of the middle second air path 141 closest to the center of the circle, and of course, the position of the air path interface 110 may be changed according to actual design conditions as long as the air path interface is disposed on the second air path 141.

Preferably, the suction cup further comprises a side wall 30 perpendicular to the top surface 10, the side wall 30 is disposed along the periphery of the suction cup and the periphery of the sheet fork groove 200; the first vacuum air path 130 and the second vacuum air path 140 are both parallel to the top surface 10, and plugs 31 are disposed at intersection points of the first vacuum air path 130 and the second vacuum air path 140 and the side wall 30. In an exemplary embodiment, as shown in fig. 1-2, the first air channel 131 and the sidewall 30 have three intersection points, each of the second air channels 141 and the sidewall 30 has an intersection point, the third air channel 142 and each of the fourth air channels 143 and the sidewall 30 have an intersection point, and the intersection points are blocked by the plugs 31 to prevent air leakage, although the intersection points are not limited to the above description, in practice, the intersection points of the vacuum air channels and the sidewall 30 are set according to actual conditions, in practice, the setting of the vacuum air channels is limited by the processing technology used, in a preferred processing technology, the vacuum air channels are processed by opening air channels into the inside of the chuck through the sidewall 30, and the intersection points are actually a process gap.

Preferably, the top surface 10 includes a plurality of separation grooves 11, and the separation grooves 11 are disposed between regions of the top surface 10 corresponding to substrates with different diameters. In an exemplary embodiment, as shown in fig. 1, an annular separation groove 11 is provided between the region for carrying a substrate having a diameter of 8 inches and the region for carrying a substrate having a diameter of 12 inches, and preferably, the region for carrying a substrate having a diameter of 12 inches is also provided with a separation groove 11 at the outer periphery thereof. The separation grooves can seal the vacuum adsorption area 300 and a cavity formed by the substrate on one hand, and can separate different vacuum adsorption areas 300 on the other hand, so that different areas can be identified conveniently in the use process.

Preferably, the bottom surface 20 includes a support structure 400, and the support structure 400 includes a plurality of radially outwardly diverging ribs 410. Preferably, the bottom surface 20 further comprises a weight-reducing structure 500, and the weight-reducing structure 500 comprises a step 510 descending from the center of the suction cup to the edge of the suction cup. In an exemplary embodiment, as shown in fig. 3, the supporting structure 400 includes 9 ribs 410 diverging outward from the center, the ribs 410 can increase the structural rigidity of the suction cup, and the ribs are disposed to avoid the portions of the blade fork grooves 200, the angles between two adjacent ribs 410 are the same except for the blade fork grooves 200 of the portions of the adjacent blade fork grooves 200, of course, in other embodiments, the positional relationship of the ribs 410 is not limited thereto, and may be disposed at different angles. Preferably, a weight reducing structure 400 is further disposed between two adjacent ribs 410, the weight reducing structure 500 includes a step 510 descending from the center of the suction cup to the edge of the suction cup, the weight reducing structures 500 between two ribs 410 may be disposed in the same structure, and may be disposed in different structures, preferably, the weight reducing structures 500 between two symmetrical ribs 410 are the same, and more preferably, the weight reducing structures 500 between the ribs 410 are arranged at intervals, and the weight reducing structures 500 arranged at intervals are the same. The distance between each step and the number of steps in the weight-reducing structure can be designed according to actual conditions, and preferably, the number of steps in each weight-reducing structure is 2. In other embodiments, the bottom surface may be designed only as a weight-reducing structure and not as a support structure.

Preferably, a positioning platform 600 is further disposed at the center of the bottom surface, and the positioning platform 600 is used for being connected with the wafer bearing table in a positioning manner. In an exemplary embodiment, as shown in fig. 3, the positioning platform 600 is placed at the center of the bottom surface of the suction cup and is connected with the wafer supporting platform by a positioning pin, so as to accurately position the suction cup on the wafer supporting platform carrying the suction cup.

The invention also provides a movement system which comprises the sucker, a wafer bearing table, a vacuum source and an air pipe, wherein the wafer bearing table is connected with the bottom surface of the sucker, and the vacuum source is connected with an air passage interface of the sucker through the air pipe. In an exemplary embodiment, the number of the air pipes is two, and the two air pipes are respectively connected to the two air circuit interfaces 110, and of course, the number of the air pipes is matched with the number of the air circuit interfaces 110, so that the air circuit interfaces 110 are ensured to be communicated with the air pipes. Through the arrangement of the air pipe, the work of the sucker for adsorbing the substrate can be effectively finished, and the sucker is convenient to operate and simple in structure.

Further fluid simulation test results carried out by the invention show that only the sucker with the weight-reducing structure 500 is used, and the sucker adsorbs the surface type (maximum 9.3 mu m) of the substrate after the substrate is adsorbed; meanwhile, the suckers of the weight-reducing structure 500 and the support structure 400 are used under the condition that the total weight is the same, and the suckers absorb the surface shape (maximum 4.7 microns) of the substrate after the substrate, so that the precision of the surface shape of the substrate after the substrate is absorbed is obviously improved by using the suckers of the weight-reducing structure 500 and the support structure 400. According to the invention, under the conditions of simplifying the structure of the sucker and reducing the cost of the sucker, the surface shape precision of the substrate after the substrate is adsorbed is ensured through the special design of the distribution of the symmetrical gas circuits, the weight reduction structure and the support structure.

In summary, in the suction cup and the motion system provided by the present invention, the suction cup includes: the vacuum air channels are arranged between the top surface and the bottom surface; each vacuum gas circuit comprises a gas circuit interface and a plurality of gas suction ports arranged on the top surface, all the gas circuit interfaces are uniformly distributed by taking the circle center of the sucking disc as the center, and all the gas circuit interfaces are intensively arranged in a first area which takes the circle center of the sucking disc as the center and has the radius of r; the sheet fork groove is arranged on the top surface along the diameter direction of the sucker and is used for being matched with a sheet fork; each vacuum gas circuit is used for being matched with a substrate with one diameter, and all the vacuum gas circuits are arranged in a manner of avoiding the grooves of the sheet forks. So dispose for the gas circuit interface is concentrated and is set up at the centre of a circle periphery, guarantees that the convenient trachea of switching on the vacuum source of gas circuit interface, simplifies the structure of trachea junction, and piece fork groove structure is simple, processing is convenient and the processing cost is low, avoids using the complicated sliding ring structure of structure and the very high pin structure of cost, has guaranteed better adsorption effect simultaneously.

The above description is only for the purpose of describing the preferred embodiments of the present invention, and is not intended to limit the scope of the present invention, and any variations and modifications made by those skilled in the art based on the above disclosure are within the scope of the appended claims.

Claims

1. A chuck having a top surface for supporting a substrate and a bottom surface for engaging a stage, the chuck comprising:

more than two vacuum gas circuits arranged between the top surface and the bottom surface; each vacuum gas circuit comprises a gas circuit interface and a plurality of gas suction ports arranged on the top surface, all the gas circuit interfaces are uniformly distributed by taking the circle center of the sucking disc as the center, and all the gas circuit interfaces are intensively arranged in a first area which takes the circle center of the sucking disc as the center and has the radius of r; and

the sheet fork groove is arranged on the top surface along the diameter direction of the sucker and is used for being matched with a sheet fork;

each vacuum gas path is used for being matched with a substrate with one diameter, and all the vacuum gas paths are arranged in a way of avoiding the sheet fork grooves; the more than two vacuum gas paths at least comprise a first vacuum gas path and a second vacuum gas path; the first vacuum air path comprises two first air paths, the air paths of the two first air paths are communicated, the arrangement direction of one first air path is the same as the arrangement direction of the sheet fork groove, and the air path interface is arranged on one first air path.

2. The chuck of claim 1, wherein the chuck includes two vacuum passages, a first vacuum passage and a second vacuum passage, the first vacuum passage for accommodating substrates of a first diameter, the second vacuum passage for accommodating substrates of a second diameter, the first diameter being smaller than the second diameter.

3. The suction cup according to claim 2, wherein the second vacuum air passage comprises three second air passages sequentially arranged along the first direction at intervals, a third air passage arranged along the second direction, and two fourth air passages arranged along the third direction, wherein the third air passage penetrates through the three second air passages, the two fourth air passages are respectively connected with two second air passages located at two sides of the three sequentially arranged second air passages, and the air passage interface is arranged on the middle second air passage of the three sequentially arranged second air passages.

4. The suction cup as set forth in claim 1 further comprising a sidewall perpendicular to said top surface, said sidewall being disposed along a periphery of said suction cup and a periphery of said blade fork recess; the first vacuum air path and the second vacuum air path are both parallel to the top surface, and plugs are arranged at intersection points of the first vacuum air path and the second vacuum air path and the side wall.

5. The chuck of claim 1 wherein the top surface includes a plurality of separation grooves disposed between regions of the top surface corresponding to substrates of different diameters.

6. The suction cup of claim 1 wherein said bottom surface includes a support structure comprising a plurality of ribs diverging outwardly from a center of said circle.

7. The suction cup as claimed in claim 1, wherein said bottom surface further comprises a weight-reducing structure comprising a step descending from the center of said suction cup to the edge of said suction cup.

8. The suction cup as claimed in claim 1, wherein a positioning platform is further provided at the center of the bottom surface, and the positioning platform is used for positioning connection with the wafer bearing platform.

9. A motion system comprising a suction cup according to any of claims 1-8, further comprising a stage, a vacuum source and an air tube, wherein the stage is connected to a bottom surface of the suction cup, and wherein the vacuum source is connected to an air channel interface of the suction cup via the air tube.