Air floating type leveling device and leveling equipment for wafer alignment

Abstract

The invention relates to the technical field of wafer alignment, in particular to an air floating type leveling device and leveling equipment for wafer alignment. In order to solve the problem that existing leveling equipment for wafer alignment has the defects, the novel air floating type leveling device for wafer alignment comprises an air floating sub-assembly and an air floating stator assembly, the air floating sub-assembly is located in the air floating stator assembly, and the air floating sub-assembly is located in the air floating stator assembly. An annular air film gap is arranged between the axial middle parts of the air floating sub-assembly and the air floating stator assembly, the air floating stator assembly is provided with an air floating positive pressure hole communicated with the annular air film gap, and the top end part of the air floating sub-assembly is provided with a positive pressure air floating channel and a negative pressure air floating channel which are used for controlling the wafer sucking disc. The air floatation principle is ingeniously adopted, wafer alignment and leveling are achieved, the structure is simple, cost is low, installation and adjustment are convenient, meanwhile, direct friction contact between components can be avoided, and the risk that particles fall off due to friction pollute the wafer is effectively avoided.

Description

Technical Field

[0001] This invention relates to the field of wafer alignment technology, specifically to an air-floating leveling device and leveling equipment for wafer alignment. Background Technology

[0002] In the field of advanced semiconductor packaging, the packaging process of wafers often involves wafer alignment. In order to improve the density and quality of chip interconnection, it is necessary to ensure the alignment accuracy between the upper and lower wafers, which often requires ensuring the parallelism of the upper and lower wafers.

[0003] Traditional leveling equipment for wafer alignment mostly uses complex devices, such as high-precision motors, piezoelectric ceramics, position encoders, and cameras. However, these devices are mostly complex in structure and expensive, and the assembly and debugging process is often very difficult. During the leveling process, the components are constantly in contact with each other, which not only reduces the accuracy, but also inevitably causes particles to fall off due to friction, resulting in the risk of wafer contamination. Summary of the Invention

[0004] In order to solve the above-mentioned defects of existing leveling equipment for wafer alignment, the present invention provides a new air-floating leveling device and leveling equipment for wafer alignment.

[0005] This invention is achieved using the following technical solution:

[0006] An air-float leveling device for wafer alignment includes a cylindrical air-float sub-assembly and a cylindrical air-float stator assembly arranged coaxially. The air-float sub-assembly is located inside the air-float stator assembly, with its top higher than the top of the stator assembly. A circumferential air film gap is provided between the axial midpoints of the air-float sub-assembly and the air-float stator assembly. A circumferential upward air gap is provided between the upper ends of the air-float sub-assembly and the air-float stator assembly, and a circumferential downward air gap is provided between the lower ends of the air-float sub-assembly and the air-float stator assembly. (The arrangement of these three gaps allows the air-float sub-assembly to slide vertically relative to the air-float stator assembly.) The stator assembly is provided with an air-float positive pressure hole communicating with the circumferential air film gap, a micro-negative pressure vent communicating with the circumferential upward air gap, and a lower atmospheric vent communicating with the circumferential downward air gap. The part of the air-float sub-assembly above the air-float stator assembly is provided with an air inlet and an upper atmospheric vent. The air-float sub-assembly is provided with an air inlet channel and an air outlet channel. The upper end of the air inlet channel is connected to the air inlet port, and the lower end leads to the bottom surface of the air-float sub-assembly. The upper end of the air outlet channel is connected to the upper atmospheric vent, and the lower end leads to the bottom surface of the air-float sub-assembly. The top part of the air-float sub-assembly is provided with a positive pressure air-float channel and a negative pressure air-float channel for controlling the wafer chuck.

[0007] In use, multiple of these devices are employed and arranged circumferentially between the chuck base and the wafer chuck, with the bottom surface of each air-float stator assembly sealed and fixed to the chuck base. Working principle: The air-float leveling device mainly consists of the following three air-float surfaces: ① Air intake through the positive pressure port, requiring continuous airflow (to maintain precise guiding posture), forms a circumferential air pressure film between the air-float stator assembly and the air-float stator assembly, thus forming a Z-axis guiding air-float surface between the inner and outer circumferential surfaces of the air-float stator assembly, used to guide the air-float stator assembly to move along the Z-axis; ② Air intake through the air inlet of the air-float stator assembly, passing through the intake channel, forms an air-float surface between the lower surface of the air-float stator assembly and the upper surface of the chuck base, thus forming a Z-axis height-adjusting air-float surface. The air-float stator assembly is adjusted by controlling the air intake volume. The height of the sub-component in the Z direction; ③ The air-floating surface of the wafer chuck, which is composed of the top surface of the air-floating sub-component and the lower surface of the wafer chuck, is used to control the air-floating surface of the wafer chuck. When leveling, positive pressure is supplied in the positive pressure air-floating channel to lift the wafer chuck by air-floating action. At this time, since there is a layer of air film between the wafer chuck and the top surface of the air-floating sub-component, there will be no wear caused by friction when adjusting the parallelism, and no related dust particles will be generated. After the parallelism is adjusted, negative pressure is supplied in the negative pressure air-floating channel and gradually increased until the wafer chuck is firmly adsorbed downwards. During this process, the positive pressure gradually decreases and is interrupted. Among them, since the circumferential air gap between the upper end of the air float component and the air float stator component is a non-sealed area, gas will escape and contaminate the wafer during the leveling process. Therefore, a micro negative pressure vent (equivalent to air extraction) is set to maintain the stability of air float control and prevent the overflow of contaminant particles. The other upper atmospheric vent and lower atmospheric vent are all for gas to enter and exit, ensuring control accuracy.

[0008] Furthermore, the air-float stator assembly includes a first air-float stator and a second air-float stator. The first air-float stator includes a first cylinder, with a lower annular boss integrally formed on the bottom wall of the first cylinder. The second air-float stator includes a second cylinder, with an upper annular boss integrally formed on the top wall of the second cylinder. The second air-float stator is fastened onto the first air-float stator, such that the top surface of the lower annular boss is fixed to the bottom surface of the second cylinder, and the bottom surface of the upper annular boss is fixed to the top surface of the first cylinder. The lower atmospheric vent is located at the bottom of the circumferential wall of the first cylinder. A sealed annular air cavity is formed between the outer circumferential surface of the first cylinder and the inner circumferential surface of the second cylinder. An air-float positive pressure hole is provided on the circumferential wall of the second cylinder. The circumferential wall of the first cylinder has multiple evenly distributed holes circumferentially. One end of each evenly distributed hole communicates with the sealed annular air cavity, and the other end communicates with the circumferential air film gap, which facilitates uniform gas distribution in the circumferential air film gap and facilitates control and guidance.

[0009] Furthermore, the air flotation assembly includes a columnar first air flotation, a columnar second air flotation, and a ball-head air flotation. The ball-head air flotation, the first air flotation, and the second air flotation are arranged vertically and fixedly connected in sequence. The circumferential air film gap is formed by the middle part of the first cylinder and the first air flotation. The circumferential upward air gap is formed by the upper annular boss and the ball-head air flotation. The circumferential downward air gap is formed by the bottom end of the first cylinder and the second air flotation. The structure is specified and planned.

[0010] Furthermore, the first air float, the second air float, and the ball head air float all have interconnected central holes to form air outlet pipes. The upper atmospheric vent is located on the ball head air float and is sealed and connected to the central hole on the ball head air float. The central hole on the second air float leads to the bottom surface of the second air float, making the structure more specific and standardized.

[0011] Furthermore, the ball-head air float is provided with an axial air hole communicating with the air inlet, the first air float is provided with a connection hole that is sealed and communicates with the axial air hole (in specific implementations, the sealed communication in this application can be achieved by a sealing ring), and the upper surface of the second air float is provided with an annular air groove that is sealed and communicates with the connection hole. The annular air groove has multiple air float holes that lead to the bottom surface of the second air float evenly distributed circumferentially. The structure is specific and standardized, so that the gas entering the bottom surface of the second air float is relatively uniform, which makes it easier to better adjust the height of the air float assembly in the Z direction.

[0012] Furthermore, the circumferential air film gap 13 has a gap width of 8-10 μm, the circumferential upward air gap 14 has a gap width of 0.5 mm, the circumferential downward air gap 15 has a gap width of 0.5 mm, and the radial width of the annular air cavity is 1 mm.

[0013] A leveling device for wafer alignment includes a chuck base, a plurality of air-floating leveling devices as described above, and a wafer chuck. The chuck base and the wafer chuck are distributed vertically, and the plurality of air-floating leveling devices are circumferentially distributed between the chuck base and the wafer chuck. The air-floating stator assembly in the air-floating leveling device is sealed and fixed to the chuck base.

[0014] Furthermore, the leveling device also includes a columnar magnet fixed to the center of the chuck base, which provides magnetic preload to further control the static vibration of the overall air-floating surface, thereby forming a pre-pressure in the form of magnetic preload.

[0015] Furthermore, there are three air-float leveling devices.

[0016] Furthermore, the three micro-negative pressure vents are combined into one air path, the three upper atmospheric vents are combined into one air path, the three negative pressure air flotation channels are combined into one air path, and the three lower atmospheric vents are combined into one air path, thus simplifying the air path.

[0017] The beneficial effects of this invention are as follows: This invention cleverly adopts the principle of air flotation to achieve wafer alignment and leveling. It has a simple structure, low cost, and convenient assembly and adjustment. At the same time, it can avoid direct frictional contact between components and effectively avoid the risk of friction-induced particle contamination of the wafer. Attached Figure Description

[0018] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of the overall structure of the leveling device described in this invention;

[0021] Figure 2 This is a schematic diagram of the air-float leveling device described in this invention;

[0022] Figure 3 for Figure 2 A sectional view;

[0023] Figure 4 This is a schematic diagram of the structure of the second air-floater;

[0024] Figure 5 This is a schematic diagram of the structure of the first air-float stator.

[0025] In the diagram: 1-Air-float leveling device, 11-Air-float stator assembly, 111-First air-float stator, 112-Second air-float stator, 12-Air-float stator assembly, 121-First air-float stator, 122-Second air-float stator, 123-Ball-head air-float, 13-Annular air film gap, 14-Annular upward air gap, 15-Annular downward air gap, 16-Air-float positive pressure hole, 17-Micro negative pressure vent hole, 18-Lower atmospheric vent hole, 19-Air inlet hole, 20-Upper atmospheric vent hole, 21-Sealed annular air cavity, 22-Annular air groove, 23-Air-float hole, 24-Evenly distributed hole, 25-Sealing ring, 2-Wafer chuck, 3-Chuck base, 4-Columnar magnet. Detailed Implementation

[0026] To better understand the above-mentioned objectives, features, and advantages of the present invention, the solutions of the present invention will be further described below. It should be noted that, unless otherwise specified, the embodiments of the present invention and the features thereof can be combined with each other.

[0027] Many specific details are set forth in the following description in order to provide a full understanding of the invention, but the invention may also be practiced in other ways different from those described herein; obviously, the embodiments in the specification are only some embodiments of the invention, and not all embodiments.

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

[0029] like Figure 1 , 2 As shown in Figures 3, 4, and 5, an air-float leveling device for wafer alignment includes a cylindrical air-float sub-assembly 12 and a cylindrical air-float stator assembly 11 arranged coaxially. The air-float sub-assembly 12 is located inside the air-float stator assembly 11, and the top of the air-float sub-assembly 12 is higher than the top of the air-float stator assembly 11. A circumferential air film gap 13 is provided between the axial midpoints of the air-float sub-assembly 12 and the air-float stator assembly 11. A circumferential upward air gap 14 is provided between the upper ends of the air-float sub-assembly 12 and the air-float stator assembly 11. A circumferential downward air gap 15 is provided between the lower ends of the air-float sub-assembly 12 and the air-float stator assembly 11. (The arrangement of the three gaps allows the air-float sub-assembly 12 to be positioned vertically relative to the air-float stator assembly 11.) (Sliding), the air-float stator assembly 11 is provided with an air-float positive pressure hole 16 communicating with the circumferential air film gap 13, a micro negative pressure vent hole 17 communicating with the circumferential upward air gap 14, and a lower atmospheric vent hole 18 communicating with the circumferential downward air gap 15. The part of the air-float stator assembly 12 above the air-float stator assembly 11 is provided with an air inlet hole 19 and an upper atmospheric vent hole 20. The air-float stator assembly 12 is provided with an air inlet channel and an air outlet channel. The upper end of the air inlet channel is connected to the air inlet port and the lower end leads to the bottom surface of the air-float stator assembly 12. The upper end of the air outlet channel is connected to the upper atmospheric vent and the lower end leads to the bottom surface of the air-float stator assembly 12. The top part of the air-float stator assembly 12 is provided with a positive pressure air-float channel and a negative pressure air-float channel for controlling the wafer chuck 2.

[0030] In use, multiple of these devices are employed and arranged circumferentially between the chuck base 3 and the wafer chuck 2, with the bottom surface of each air-float stator assembly 11 sealed and fixed to the chuck base 3. Working principle: The air-float leveling device 1 mainly consists of the following three air-float surfaces: ① Air intake through the positive pressure port 16, requiring continuous airflow (to maintain accurate guiding posture), forms a circumferential air pressure film between the air-float stator assembly 12 and the air-float stator assembly 11, thus forming a Z-axis guiding air-float surface between the inner circumferential surface of the air-float stator assembly 11 and the outer circumferential surface of the air-float stator assembly 12, used to guide the air-float stator assembly 12 to move along the Z-axis; ② Air intake through the air inlet of the air-float stator assembly 12, passing through the air intake channel, forms an air-float surface between the lower surface of the air-float stator assembly 12 and the upper surface of the chuck base 3, thus forming a Z-axis height-adjusting air-float surface, which is adjusted by controlling the air intake volume. The height of the throttling sub-assembly 12 in the Z direction; ③ The air flotation channel is formed by the top surface of the air flotation sub-assembly 12 and the lower surface of the wafer chuck 2 to control the air flotation surface of the wafer chuck 2. When leveling, positive pressure is supplied in the positive pressure air flotation channel so that the wafer chuck 2 is lifted by the air flotation effect. At this time, since there is a layer of air film between the wafer chuck 2 and the top surface of the air flotation sub-assembly 12, there will be no wear caused by friction when adjusting the parallelism, and no related dust particles will be generated. After the parallelism is adjusted, negative pressure is supplied in the negative pressure air flotation channel and gradually increased until the wafer chuck 2 is sucked down. During this process, the positive pressure gradually decreases and is interrupted. Since the circumferential air gap 14 between the upper ends of the air float component 12 and the air float stator component 11 is a non-sealed area, gas will escape and contaminate the wafer during the leveling process. Therefore, a micro negative pressure vent 17 (equivalent to air extraction) is provided to maintain stable air float control and prevent contaminant particles from overflowing. The other upper atmospheric vent 20 and lower atmospheric vent 18 are for gas to enter and exit, ensuring control accuracy.

[0031] In specific implementation, the air-float stator assembly 11 includes a first air-float stator 111 and a second air-float stator 112. The first air-float stator 111 includes a first cylinder, and a lower annular boss is integrally provided on the bottom end wall of the first cylinder. The second air-float stator 112 includes a second cylinder, and an upper annular boss is integrally provided on the top end wall of the second cylinder. The second air-float stator 112 is fastened onto the first air-float stator 111, such that the top surface of the lower annular boss is fixed to the bottom surface of the second cylinder, and the bottom surface of the upper annular boss is fixed to the bottom surface of the first cylinder. The top surface is fixed, and the lower atmospheric vent 18 is located at the bottom of the circumferential wall of the first cylinder. A sealed annular air cavity 21 is formed between the outer circumferential surface of the first cylinder and the inner circumferential surface of the second cylinder. The air flotation positive pressure hole 16 is provided on the circumferential wall of the second cylinder. A plurality of evenly distributed holes 24 are evenly distributed circumferentially on the circumferential wall of the first cylinder. One end of each evenly distributed hole 24 is connected to the sealed annular air cavity 21, and the other end is connected to the circumferential air film gap 13, which facilitates the uniformity of gas in the circumferential air film gap 13 and facilitates the control of the guide.

[0032] In specific implementation, the air flotation component 12 includes a columnar first air flotation 121, a columnar second air flotation 122, and a ball-head air flotation 123. The ball-head air flotation 123, the first air flotation 121, and the second air flotation 122 are arranged vertically and fixedly connected in sequence. The circumferential air film gap 13 is formed by the middle part of the first cylinder and the first air flotation 121. The circumferential upward air gap 14 is formed by the upper annular boss and the ball-head air flotation 123. The circumferential downward air gap 15 is formed by the bottom end of the first cylinder and the second air flotation 122. The structure is specified and planned.

[0033] In specific implementation, the center of the first air float 121, the second air float 122, and the ball head air float 123 are all opened with interconnected central holes to form air outlet pipes. The upper atmospheric vent 20 is provided on the ball head air float 123 and is sealed and connected to the central hole on the ball head air float 123. The central hole on the second air float 122 leads to the bottom surface of the second air float 122. The structure is specific and standardized.

[0034] In a specific implementation, the ball-head air float 123 is provided with an axial air hole communicating with the air inlet 19, the first air float 121 is provided with a connection hole that is sealed and communicated with the axial air hole (in a specific implementation, the sealed communication in this application can be achieved by the sealing ring 25), and the upper surface of the second air float 122 is provided with an annular air groove 22 that is sealed and communicated with the connection hole. The annular air groove 22 is circumferentially distributed with a plurality of air float holes 23 leading to the bottom surface of the second air float 122. The structure is specific and standardized, so that the gas entering the bottom surface of the second air float 122 is relatively uniform, which makes it easier to better adjust the height of the air float assembly 12Z.

[0035] In specific implementation, the gap width of the circumferential air film gap 13 is 8-10 μm, the gap width of the circumferential upward air gap 14 is 0.5 mm, the gap width of the circumferential downward air gap 15 is 0.5 mm, and the radial width of the annular air cavity is 1 mm.

[0036] A leveling device for wafer alignment includes a chuck base 3, multiple air-floating leveling devices 1 as described above, and a wafer chuck 2. The chuck base 3 and the wafer chuck 2 are distributed vertically, and the multiple air-floating leveling devices 1 are evenly distributed circumferentially between the chuck base 3 and the wafer chuck 2. The air-floating stator assembly 11 in the air-floating leveling device 1 is sealed and fixed to the chuck base 3.

[0037] In practice, the leveling device also includes a columnar magnet 4 fixed at the center of the chuck base 3, which is a magnetic preload to further control the static vibration of the overall air-floating surface, so as to form a pre-pressure in the form of magnetic preload.

[0038] In this specific embodiment, there are three air-float leveling devices 1. The three micro-negative pressure vents 17 are combined into one air path, the three upper atmospheric vents are combined into one air path, the three negative pressure air-float channels are combined into one air path, and the three lower atmospheric vents 18 are combined into one air path, thus simplifying the air path.

[0039] The above description is merely a specific embodiment of the present invention, enabling those skilled in the art to understand or implement the present invention. Although detailed descriptions have been provided with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments, and they should all be covered within the protection scope of the claims.

Claims

1. An air floating leveling device for wafer alignment, characterized by, The gas float subassembly (12) and the cylindrical gas float stator assembly (11) are coaxially arranged, the gas float subassembly (12) is located in the gas float stator assembly (11), the top of the gas float subassembly (12) is higher than the top of the gas float stator assembly (11), the annular gas film gap (13) is arranged between the axial middle part of the gas float subassembly (12) and the gas float stator assembly (11), the annular upper gas gap (14) is arranged between the upper end of the gas float subassembly (12) and the gas float stator assembly (11), the annular lower gas gap (15) is arranged between the lower end of the gas float subassembly (12) and the gas float stator assembly (11), the gas float positive pressure hole (16) communicated with the annular gas film gap (13), the micro-negative pressure vent hole (17) communicated with the annular upper gas gap (14), and the lower atmospheric vent hole (18) communicated with the annular lower gas gap (15) are arranged on the gas float stator assembly (11), the part of the gas float subassembly (12) higher than the gas float stator assembly (11) is provided with the air inlet hole (19) and the upper atmospheric vent hole (20), the gas float subassembly (12) is provided with the air inlet channel and the air outlet channel, the upper end of the air inlet channel is communicated with the air inlet, and the lower end of the air inlet channel is communicated with the bottom surface of the gas float subassembly (12), the upper end of the air outlet channel is communicated with the upper atmospheric vent hole, and the lower end of the air outlet channel is communicated with the bottom surface of the gas float subassembly (12), and the top end of the gas float subassembly (12) is provided with the positive pressure gas float channel and the negative pressure gas float channel for controlling the wafer chuck (2).

2. The air floating leveling device for wafer alignment according to claim 1, wherein, The gas float stator assembly (11) comprises the first gas float stator (111) and the second gas float stator (112), the first gas float stator (111) comprises a first cylinder, the bottom end wall of the first cylinder is integrally provided with a lower circular ring boss, the second gas float stator (112) comprises a second cylinder, the top end wall of the second cylinder is integrally provided with an upper circular ring boss, the second gas float stator (112) is buckled on the first gas float stator (111), so that the top surface of the lower circular ring boss is fixed with the bottom surface of the second cylinder, and the bottom surface of the upper circular ring boss is fixed with the top surface of the first cylinder, the lower atmospheric vent hole (18) is located at the bottom of the circumferential wall of the first cylinder, the outer circumferential surface of the first cylinder and the inner circumferential surface of the second cylinder form a sealed annular air cavity (21), the gas float positive pressure hole (16) is arranged on the circumferential wall of the second cylinder, and a plurality of uniform distribution holes (24) are uniformly distributed on the circumferential wall of the first cylinder, one end of each uniform distribution hole (24) is communicated with the sealed annular air cavity (21), and the other end of each uniform distribution hole (24) is communicated with the annular gas film gap (13).

3. The air floating leveling device for wafer alignment according to claim 2, wherein, The gas float subassembly (12) comprises the cylindrical first gas float subassembly (121), the cylindrical second gas float subassembly (122) and the ball head gas float (123), the ball head gas float (123), the first gas float subassembly (121) and the second gas float subassembly (122) are arranged in sequence and fixedly connected in sequence, the annular gas film gap (13) is formed between the middle part of the first cylinder and the first gas float subassembly (121), the annular upper gas gap (14) is formed between the upper circular ring boss and the ball head gas float (123), and the annular lower gas gap (15) is formed between the bottom end part of the first cylinder and the second gas float subassembly (122).

4. The air floating leveling device for wafer alignment according to claim 3, wherein, The center hole of the first gas floating mover (121), the second gas floating mover (122) and the spherical head gas floating (123) are connected to each other to form a gas outlet pipeline. The upper atmospheric air vent hole (20) is arranged on the spherical head gas floating (123) and is in sealed communication with the center hole of the spherical head gas floating (123). The center hole of the second gas floating mover (122) is connected to the bottom surface of the second gas floating mover (122).

5. The air floating leveling device for wafer alignment according to claim 4, wherein, The spherical head gas floating (123) is provided with an axial gas hole in communication with the gas inlet hole (19). The first gas floating mover (121) is provided with a connecting hole in sealed communication with the axial gas hole. The upper surface of the second gas floating mover (122) is provided with an annular gas groove (22) in sealed communication with the connecting hole. The annular gas groove (22) is uniformly distributed with a plurality of gas floating holes (23) on the circumference, which are connected to the bottom surface of the second gas floating mover (122).

6. The air floating leveling device for wafer alignment according to claim 5, wherein, The gap width of the annular gas film gap 13 is 8-10 μm. The gap width of the upper annular gas gap 14 is 0.5 mm. The gap width of the lower annular gas gap 15 is 0.5 mm. The radial width of the annular gas cavity is 1 mm.

7. A leveling apparatus for wafer alignment, characterized by, The leveling device comprises a chuck base (3), a plurality of gas floating leveling devices (1) as described above, and a wafer chuck (2). The chuck base (3) and the wafer chuck (2) are arranged in a vertical manner. The plurality of gas floating leveling devices (1) are uniformly distributed between the chuck base (3) and the wafer chuck (2) in a circumferential manner. The gas floating stator assembly (11) in the gas floating leveling device (1) is fixedly connected to the chuck base (3).

8. The leveling apparatus for wafer alignment of claim 7, wherein, The leveling device further comprises a cylindrical magnet (4) fixed to the center of the chuck base (3).

9. The leveling apparatus for wafer alignment of claim 8, wherein, The gas floating leveling device (1) is three.

10. The leveling apparatus for wafer alignment of claim 9, wherein, The three micro-negative pressure vent holes (17) are combined into one gas path through the gas path. The three upper atmospheric air vent holes are combined into one gas path through the gas path. The three negative pressure gas floating channels are combined into one gas path through the gas path. The three lower atmospheric air vent holes (18) are combined into one gas path through the gas path.

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