An air-floating lifting and rotating platform

Abstract

The present invention discloses an air-floating lifting and rotating platform, belonging to the field of precision instrument technology. The platform comprises a base, a slider, and a stage. The slider is maintained in a suspended state within the base by gas power and can be adjusted in the vertical direction in response to external loads. The stage and the slider are isolated and contacted by an air film, and the stage can rotate within a plane parallel to the surface of the slider. The slider comprises a housing, a thrust bearing is provided on the upper portion of the housing, a radial bearing is provided inside the thrust bearing, the stage and the thrust bearing have clearances between the upper and lower surfaces to form a cavity, and the stage and the radial bearing have clearances inside the cavity to form a cavity. The thrust bearing has an air path for releasing high-pressure air into the cavity, and the stage is connected to a motor. The present invention reduces contact friction to improve lifting and rotation accuracy, thereby enhancing wafer detection and alignment efficiency.

Description

Technical Field

[0001] The invention belongs to the technical field of precision instruments, and in particular relates to an air-floating lifting and rotating platform. Background Art

[0002] Applications such as scientific research, optical inspection, precision measurement, and rotary machining often require high-precision turntables, which rotate the object 360° to measure or process it. An air-bearing turntable uses high-pressure gas, which is throttled and then passed into a tiny gap. This separates the rotating and stationary parts with a tiny air film, achieving near-zero friction during rotation. This turntable offers advantages such as high precision, high speed, zero friction, no lubrication, and noise-free operation, along with excellent speed control. As air-bearing turntable technology matures, its application is becoming increasingly widespread.

[0003] During semiconductor inspection and processing, due to the focusing requirements of the optical system, the wafer on the stage needs to be moved longitudinally to adapt to the appropriate focal length. In addition, due to the angle of the wafer during wafer loading, there will be a certain deviation. Therefore, while meeting the focus, it is also necessary to rotate it to adjust the deviation of the wafer relative to the optical system. The Korean invention patent with application number KR1020247038733 discloses a substrate conveying mechanism and an exposure platform system. The conveying mechanism includes a rotating seat, an adsorption component, a base and a rotating drive member; the rotating seat is rotatably set on the base by the rotating drive member. When compensating for the circumferential position error of the loaded wafer, the substrate conveying mechanism and exposure platform system only need to adaptively drive the rotating seat in the substrate conveying mechanism to rotate, which simplifies the overall structure, improves the input-output ratio, and is conducive to achieving high rotation accuracy.

[0004] The existing technology typically uses an external drive device to achieve the lifting and lowering movement of the stage, and uses contact-type mechanical guide rails to achieve lifting guidance. However, these methods have the following drawbacks: the mechanical guide rails rely on sliding or rolling contact, which inevitably causes friction and wear during movement. After long-term use, this leads to increased guide clearance and a significant reduction in positioning accuracy. Furthermore, the heat generated by the motor during operation is conducted through the guide rail, causing thermal expansion of the metal track, further exacerbating motion deviations. Therefore, it is necessary to provide a device that can achieve low interference in both the rotational and lifting movements of the platform to ensure high-precision wafer inspection processes. Summary of the Invention

[0005] The object of the present invention is to provide an air-floating lifting and rotating platform with high motion precision, which can realize stable rotation and lifting of wafers.

[0006] The technical solutions adopted by the present invention to achieve the above-mentioned purpose are:

[0007] An air-floating lifting and rotating platform includes: a base, a slider, and a carrier. The slider is kept in suspension by gas power in the base and can adjust its position in the vertical direction in response to external loads. The carrier and the slider are isolated and contacted by an air film, and the carrier can rotate in a plane parallel to the surface of the slider. The slider is kept in suspension by gas power in the base, forming an air-floating guide rail, so that the slider does not generate sliding friction or rolling friction with the base during the process of adjusting its position in the vertical direction. Compared with contact-type mechanical guide rails, the present invention can achieve higher repeatability positioning accuracy of the slider in the vertical direction, improving the accuracy of focal length adjustment in the wafer inspection process. The carrier is suspended on the slider by air film isolation, so that the carrier has no friction contact with the slider during the process of adjusting the rotation angle above the slider, improving the adjustment accuracy of angle deviation in the wafer inspection process.

[0008] The present invention forms a highly integrated structure by combining a base, a slider and a stage. Different from the lifting and rotating motion stage using a stacking method, the technical solution structure of the present invention is compact in size, which can reduce the space occupied in the dust-free environment of wafer inspection and improve the utilization rate of the dust-free space.

[0009] Preferably, the slider includes a housing, a thrust bearing disposed on the upper portion of the housing, a radial bearing disposed within the inner portion of the thrust bearing, a cavity formed by clearances between the upper and lower surfaces of the stage and the thrust bearing, and a cavity formed by clearances between the stage and the inner portion of the radial bearing. The thrust bearing includes an air path for releasing high-pressure air into the cavity, and the stage is connected to a motor. When the motor drives the stage to rotate, air is released through the air path into the cavities on the upper and lower surfaces of the thrust bearing, forming a uniform air film between the stage and the thrust bearing. This allows the stage to stably float above the thrust bearing and rotate without generating contact friction, thereby achieving high-precision rotation angle adjustment of the stage.

[0010] Preferably, the air path includes: a first air supply hole provided on the side of the thrust bearing, a second air supply hole connected to the first air supply hole and penetrating the upper and lower surfaces of the thrust bearing, and the second air supply hole is annular.

[0011] Preferably, the top of the thrust bearing has an annular groove connected to the second air supply hole, and the radial cross-sectional width of the annular groove is greater than the radial cross-sectional width of the second air supply hole. When the gas is released to the top of the thrust bearing through the second air supply hole, it passes through the annular groove. After the airflow output from the second air supply hole collides with the side of the carrier near the upper surface of the thrust bearing, part of the airflow diffuses laterally away from the center of impact, while the other part of the airflow contacts the sidewalls and bottom of the annular groove to form a vortex, and is pushed upward by the subsequent new airflow to contact the carrier again. Through the combined effect of the airflow that continuously forms vortices and the stable diffusion of the airflow, the carrier obtains a stable air film support, improves the suspension stability of the carrier, and helps prevent the carrier from tilting due to unstable air film support. On the one hand, the possibility of wear caused by relative sliding of the wafer is reduced, and on the other hand, the possibility of wafer deviation or tilt affecting focal length adjustment is reduced.

[0012] Preferably, an annular elastic member is provided in the annular groove, and the elastic member has a top portion that contacts and supports the loading platform. When the thrust bearing releases high-pressure air, the top portion of the elastic member is compressed and deformed and does not contact the loading platform.

[0013] Preferably, the elastic member includes an elastic ring, the cross-section of which is a U-shape with an opening facing downward, and the open end of the elastic ring is fixed to the surface of the annular groove to form a closed space. When the thrust bearing does not release high-pressure air, the stage is not supported by the air film. At this time, the stage contacts the top of the elastic ring in the annular groove, realizing elastic support of the stage by the elastic ring. When the slider is subject to vibration interference, the vibration interference passes through the housing and the thrust bearing in sequence. At this time, the elastic ring, connected to the annular groove on the upper surface of the thrust bearing, can isolate and absorb the transmission of vibration interference to the stage, thereby reducing the transmission of vibration from the stage to the wafer carried above it, and improving the position accuracy of the wafer before the angle deviation is adjusted.

[0014] When the thrust bearing releases high-pressure air to support the carrier, the airflow output from the second air supply hole collides with the side of the carrier close to the upper surface of the thrust bearing. Part of the airflow diffuses to the side away from the center of impact, and the other part of the airflow contacts the top of the elastic ring downward to form a vortex. Since the U-shaped opening of the elastic ring and the annular groove form a closed space, the high-pressure airflow acts on the top of the elastic ring, causing the elastic ring to be flattened in the axial direction and expanded in the radial direction and accommodated in the annular groove. At this time, the top of the elastic ring loses the supporting contact with the carrier, so that the carrier can be stably supported and suspended by the air film. When the air supply to the thrust bearing is stopped, the top of the elastic ring loses the pressure of the gas and recovers its deformation, causing it to expand in the axial direction and achieve supporting contact with the carrier. At the same time, the carrier The support of the air film is lost, and the platform falls and squeezes the elastic ring. The gas compression in the closed space formed by the elastic ring and the annular groove dissipates the energy of the platform's fall, and the platform is smoothly lowered. This can avoid the platform's rapid fall after ventilation is stopped and the impact on the thrust bearing. While avoiding the problem of damage to the motor caused by interference, it also avoids the problem of reduced platform working accuracy. The elastic ring can automatically cancel the contact friction with the platform when air is supplied to the thrust bearing, and can automatically cushion the platform's fall impact when air supply is stopped, and isolate the transmission of vibration interference. The above structure does not require active intervention and control to achieve stable lifting and lowering of the platform and high-precision maintenance of the wafer position. It has a simple structure, saves manufacturing costs and control difficulty.

[0015] Preferably, the worktable includes a spacer, an upper plate and a lower plate, the spacer is arranged on the inner side of the radial bearing, the upper plate is arranged on the upper part of the spacer and connected to the motor, the lower plate is arranged on the lower part of the thrust bearing, the upper plate and the upper surface of the thrust bearing are clearance matched, the lower plate and the lower surface of the thrust bearing are clearance matched, and the spacer and the inner side of the radial bearing are clearance matched.

[0016] Preferably, the radial bearing side surface is uniformly distributed along the circumference, connected to the second air supply holes and inclined at the same angle as the stage's rotation direction, thereby reducing rotational resistance and achieving uniform pressure distribution. High-pressure gas entering the first air supply holes is partially discharged through the second air supply holes, while the remaining portion is discharged through the rotation guide holes to the surface of the stage that has a clearance fit with the inner side of the radial bearing. This reduces resistance to the stage's rotational motion and suppresses air vibration, which helps reduce the transmission of air vibration through the stage to the motor, thereby reducing the motor's excess power output.

[0017] Preferably, a rotation guide groove is provided on the outer periphery of the spacer, the rotation guide groove is arranged correspondingly to the rotation guide hole, and the rotation guide groove and the rotation guide hole extend in the same direction. The rotation guide groove continuously receives the airflow output by the rotation guide hole, further reducing the rotation resistance.

[0018] Preferably, the bottom of the loading platform is rotatably connected to a rotating shell, and the rotating shell is spaced apart inside the shell.

[0019] Compared with the prior art, the present invention has the following beneficial effects: through the air-floating lifting guide structure and air-floating rotation, the focusing accuracy and angle adjustment accuracy in wafer detection are improved; the base, slider and stage form a highly integrated structure, which improves the space utilization rate of the dust-free environment; the eddy current generated by the annular groove improves the stability of the air film and realizes uniform distribution of air pressure, improves the stability of the stage suspension, and avoids detection errors and wafer wear caused by the tilt of the stage; the elastic part isolates the vibration transmission when the stage is not suspended, and improves the position maintenance accuracy before the wafer rotates; the elastic part automatically deforms and loses contact with the stage in the ventilation state of the thrust bearing, preventing contact friction from affecting the accuracy; the elastic part buffers the contact with the falling stage at the moment of stopping ventilation, reduces motor interference, and protects the thrust bearing and the stage from wear; the rotating guide hole and the rotating guide groove reduce the resistance of the stage rotation, reduce air vibration and improve rotation stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a schematic diagram of the overall structure of an air-floating lifting and rotating platform;

[0021] Figure 2 Schematic diagram of the position of the base, slider and stage;

[0022] Figure 3 It is a cross-sectional schematic diagram of the slider and the stage;

[0023] Figure 4 for Figure 3 A schematic cross-sectional view at AA;

[0024] Figure 5 for Figure 3 A magnified schematic diagram of area A in the middle under short-term conditions;

[0025] Figure 6 for Figure 3 Middle A is an enlarged schematic diagram of area under ventilation state;

[0026] Figure 7 Schematic cross-sectional view of the slider and the loading platform in the second embodiment of the present invention;

[0027] Figure 8 Schematic diagram of the rotating shell structure.

[0028] Figure numbers: base 1; thrust bearing 11; radial bearing 12; slider 2; housing 21; rotating shell 22; stage 3; spacer 31; upper plate 32, lower plate 33; rotation guide groove 311; thrust bearing 4; first air supply hole 41; second air supply hole 42; annular groove 43; radial bearing 5; rotation guide hole 51; motor 6; elastic member 7; elastic ring 71; first fin 8; second fin 9. DETAILED DESCRIPTION

[0029] The technical solution of the present invention is further described in detail below with reference to the specific embodiments and the accompanying drawings:

[0030] Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0031] Example 1:

[0032] See also Figure 1 - Figure 4 , an air-floating lifting and rotating platform, including: a base 1, a slider 2 and a loading platform 3. The slider 2 maintains a suspended state in the base 1 by gas power, and can adjust its position in the vertical direction in response to external loads. The loading platform 3 and the slider 2 are isolated and contacted by an air film, and the loading platform 3 can rotate in a plane parallel to the surface of the slider 2.

[0033] It should be noted that:

[0034] The base 1 is a rectangular frame with a rectangular guideway at its center, guiding the lifting and lowering motion of the slider 2. Each of the four inner walls of the guideway is equipped with an array of air holes, which eject compressed air to levitate the slider 2. An air supply line is integrated into the base 1, connected to an external air pump to provide a steady flow of air to the air hole array.

[0035] Slider 2 is a rectangular block with a transverse cross-section slightly smaller than that of the guide rail channel. The slider 2's perimeter and the inner wall of the guide rail form a cavity. When compressed air is ejected from the air hole array, it forms an air film between the slider 2 and the inner wall of the guide rail channel, causing the slider 2 to levitate.

[0036] The slider 2 is connected to an external load, and the air pressure on different sides is adjusted to achieve smooth lifting. The external load in the present invention includes but is not limited to a counterweight cylinder.

[0037] The base 1 is equipped with an air pressure sensor for monitoring the pressure change of the air film. The air pressure sensor is connected to a control system for receiving the signal of the air pressure sensor and dynamically adjusting the air pressure of different air holes to keep the slider 2 balanced.

[0038] The base 1 is connected to an emergency brake mechanism: the emergency brake mechanism is used to support the slider 2 to prevent collision when there is a sudden power outage or gas supply failure.

[0039] The slider 2 is kept suspended within the base 1 by gas power, forming an air-floating guide rail. This allows the slider 2 to avoid sliding or rolling friction with the base 1 during vertical position adjustment. Compared to contact-type mechanical guide rails, the present invention can achieve higher vertical repeatability of the slider 2, thereby improving the accuracy of focal length adjustment in the wafer inspection process. The stage 3 is suspended on the slider 2 by air film isolation, allowing the stage 3 to avoid frictional contact with the slider 2 during rotational angle adjustment above the slider 2, thereby improving the accuracy of angular deviation adjustment in the wafer inspection process.

[0040] The present invention forms a highly integrated structure by combining a base 1, a slider 2 and a stage 3. Different from a lifting and rotating motion stage using a stacking method, the technical solution structure of the present invention is compact in size, which can reduce the space occupied in the dust-free environment of wafer inspection and improve the utilization rate of the dust-free space.

[0041] The slider 2 includes a housing 21, with a thrust bearing 4 positioned above it. A radial bearing 5 is positioned within the thrust bearing 4. The upper and lower surfaces of the stage 3 and the thrust bearing 4 are spaced apart to form a cavity. The stage 3 and the inner surface of the radial bearing 5 are spaced apart to form a cavity. The thrust bearing 4 has an air path for releasing high-pressure air into the cavity. The stage 3 is connected to a motor 6. When the motor 6 drives the stage 3 to rotate, air is released through the air path into the cavities on the upper and lower surfaces of the thrust bearing 4, forming a uniform air film between the stage 3 and the thrust bearing 4. This allows the stage 3 to stably float above the thrust bearing 4 and rotate without contact friction, enabling high-precision rotation angle adjustment of the stage 3.

[0042] The air path includes: a first air supply hole 41 provided on the side of the thrust bearing 4, and a second air supply hole 42 connected to the first air supply hole 41 and penetrating the upper and lower surfaces of the thrust bearing 4. The second air supply hole 42 is annular.

[0043] The top of the thrust bearing 4 has an annular groove 43 connected to the second air supply hole 42. The radial cross-sectional width of the annular groove 43 is greater than the radial cross-sectional width of the second air supply hole 42. When the gas is released to the top of the thrust bearing 4 through the second air supply hole 42, it passes through the annular groove 43. After the airflow output from the second air supply hole 42 collides with the side of the stage 3 near the upper surface of the thrust bearing 4, part of the airflow diffuses laterally away from the center of impact, while the other part of the airflow contacts the sidewalls and bottom of the annular groove 43 to form a vortex, which is then pushed upward by the subsequent new airflow to contact the stage 3 again. Through the combined effect of the airflow that continuously forms vortices and the stable diffusion of the airflow, the stage 3 obtains a stable air film support, improves the suspension stability of the stage 3, and helps prevent the unstable air film support from causing the stage to tilt. On the one hand, this reduces the possibility of wear caused by relative sliding of the wafer, and on the other hand, reduces the possibility of wafer offset or tilt affecting focal length adjustment.

[0044] An annular elastic member 7 is provided in the annular groove 43 . The elastic member 7 has a top portion that contacts and supports the loading platform 3 . When the thrust bearing 4 releases high-pressure air, the top portion of the elastic member 7 is compressed and deformed and does not contact the loading platform 3 .

[0045] See also Figure 5 - Figure 6 The elastic member 7 includes an elastic ring 71. The cross-section of the elastic ring 71 is a U-shape with an opening facing downward. The open end of the elastic ring 71 is fixed to the groove surface of the annular groove 43 to form a closed space. When the thrust bearing 4 does not release high-pressure air, the stage 3 is not supported by the air film. At this time, the stage 3 contacts the top of the elastic ring 71 in the annular groove 43, realizing the elastic support of the stage 3 by the elastic ring 71. When the slider 2 is subject to vibration interference, the vibration interference passes through the housing 21 and the thrust bearing 4 in sequence. At this time, the elastic ring 71 is connected to the annular groove 43 on the upper surface of the thrust bearing 4, which can isolate and absorb the transmission of vibration interference to the stage 3, thereby reducing the vibration transmission from the stage 3 to the wafer carried above it, and improving the position maintenance accuracy of the wafer before the angle deviation is adjusted;

[0046] When the thrust bearing 4 releases high-pressure air to support the stage 3, the airflow output from the second air supply hole 42 collides with the side of the stage 3 close to the upper surface of the thrust bearing 4, and part of the airflow diffuses to the side away from the center of collision, and the other part of the airflow contacts the top of the elastic ring 71 downward to form a vortex. Since the U-shaped opening of the elastic ring 71 and the annular groove 43 form a closed space, the high-pressure airflow acts on the top of the elastic ring 71, causing the elastic ring 71 to be flattened in the axial direction and expanded in the radial direction and accommodated in the annular groove 43. At this time, the top of the elastic ring 71 loses the supporting contact with the stage 3, so that the stage 3 can be stably supported and suspended by the air film. When the air supply to the thrust bearing 4 is stopped, the top of the elastic ring 71 recovers its deformation after losing the pressure of the gas, causing it to expand in the axial direction and achieve supporting contact with the stage 3. The carrier 3 loses the support of the air film and falls, squeezing the elastic ring 71. The gas compression in the closed space formed by the elastic ring 71 and the annular groove 43 dissipates the energy of the falling impact of the carrier 3, and achieves a smooth descent of the carrier 3. It can avoid the rapid drop of the carrier 3 after the ventilation is stopped and the impact on the thrust bearing 4. While avoiding the problem of damage to the motor 6 due to interference, it also avoids the problem of reduced working accuracy of the carrier 3. The elastic ring 71 can automatically cancel the contact friction on the thrust bearing 4 when supplying air to the thrust bearing 4, and can automatically cushion the falling impact of the carrier 3 when the air supply is stopped, and isolate the transmission of vibration interference. The above structure does not require active intervention and control to achieve stable lifting and lowering of the carrier 3 and high-precision maintenance of the wafer position. It has a simple structure, saving manufacturing costs and control difficulty.

[0047] The loading platform 3 includes a spacer 31, an upper plate 32 and a lower plate 33. The spacer 31 is arranged on the inner side of the radial bearing 5, the upper plate 32 is arranged on the upper part of the spacer 31 and is connected to the motor 6, and the lower plate 33 is arranged on the lower part of the thrust bearing 4. The upper plate 32 and the upper surface of the thrust bearing 4 are clearance matched, the lower plate 33 and the lower surface of the thrust bearing 4 are clearance matched, and the spacer 31 and the inner side of the radial bearing 5 are clearance matched.

[0048] The radial bearing 5 is circumferentially distributed with rotation guide holes 51, which communicate with the second air supply holes 42. The rotation guide holes 51 are tilted at the same angle as the rotation direction of the stage 3, thereby reducing rotational resistance and achieving uniform pressure distribution. The high-pressure gas entering the first air supply holes 41 is partially discharged through the second air supply holes 42, while the remaining portion is discharged through the rotation guide holes 51 to the surface of the stage 3 that has a clearance fit inside the radial bearing 5. This reduces resistance to the rotational motion of the stage 3 and suppresses air vibration, which helps reduce the transmission of air vibration through the stage 3 to the motor 6, thereby reducing the additional power output of the motor 6.

[0049] The spacer 31 is provided with a rotation guide groove 311 on its outer periphery. The rotation guide groove 311 is positioned corresponding to the rotation guide hole 51 and extends in the same direction as the rotation guide hole 51. The rotation guide groove 311 continuously receives the airflow output by the rotation guide hole 51, further reducing the rotation resistance.

[0050] The bottom of the stage 3 is rotatably connected to a rotating shell 22 , and there is a gap between the rotating shell 22 and the housing 21 .

[0051] Example 2:

[0052] See also Figure 7 - Figure 8 On the basis of the first embodiment of the present invention, the rotating shell 22 is located above the outer side of the motor 6, and there is a gap between the rotating shell 22 and the inner side of the housing 21. The first fin 8 is provided on the outer side of the rotating shell 22, and the second fin 9 is provided on the inner side of the rotating shell 22. There is a gap between the lower plate 33 and the inner side of the housing 21. The first fin 8 is provided in the gap, and high-pressure air can pass through the cavity on the lower surface of the thrust bearing 4 and act on the first fin 8.

[0053] It should be noted that the gas entering the gap can act on the first fins 8 to rotate the rotating shell 22 .

[0054] An exhaust hole 210 is provided at the center of the bottom of the housing 21 . The second fins 9 are installed at an angle such that when the rotating shell 22 rotates, the airflow generated inside the rotating shell 22 forms a flow pattern that converges toward the central axis.

[0055] The high-pressure gas introduced into the thrust bearing 4 is released to the second air supply hole 42 through the first air supply hole 41. The gas reaches the cavity formed by the upper and lower surfaces of the thrust bearing 4 and the stage 3 to form an air film, thereby forming an air-floating support for the stage 3. The high-pressure airflow passing through the lower surface of the thrust bearing 4 forms an air film while flowing into the gap. The airflow flowing downward in the gap acts on the first fin 8 and drives the rotating shell 22 to rotate the second fin 9 inside it, thereby realizing heat dissipation for the motor 6. By lowering the temperature of the motor 6 and reducing the transfer of high temperature to the stage 3, the possibility of thermal deformation of the shell 21 and the stage 3 is reduced, thereby reducing and minimizing the influence of thermal deformation on the air film.

[0056] The eddy currents generated by the rotation of the second fin 9 converge toward the center, which can avoid the possibility of the air flow diffusion affecting the air film in the opposite direction, and the eddy currents gathered in the center can effectively discharge the hot air from the exhaust hole 210, without the need for external power to achieve efficient heat dissipation, and will not affect the stability of the air film, thereby improving the rotation accuracy of the worktable 3.

[0057] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the invention can be embodied in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive, and the scope of the invention is defined by the appended claims, not the foregoing description, and all variations within the meaning and range of equivalents of the claims are intended to be included therein. Any reference sign in a claim should not be construed as limiting the claim to which it relates.

Claims

1. An air-floating lifting and rotating platform, comprising: A base (1), a slider (2) and a loading platform (3), characterized in that: the slider (2) maintains a suspended state in the base (1) by gas power and can adjust its position in the vertical direction in response to an external load; the loading platform (3) and the slider (2) are in contact with each other through an air film isolation; the loading platform (3) can rotate in a plane parallel to the surface of the slider (2); the slider (2) includes a shell (21); a thrust bearing (4) is provided on the upper part of the shell (21); the loading platform (3) and the upper and lower surfaces of the thrust bearing (4) are clearance-matched to form a cavity; the thrust bearing (4) has an air path for releasing high-pressure air into the cavity; the air path includes: a first air supply hole provided on the side of the thrust bearing (4); (41), a second air supply hole (42) connected to the first air supply hole (41) and penetrating the upper and lower surfaces of the thrust bearing (4), the top of the thrust bearing (4) has an annular groove (43) connected to the second air supply hole (42), an annular elastic member (7) is provided in the annular groove (43), the elastic member (7) has a top that contacts and supports the worktable (3), when the thrust bearing (4) releases high-pressure air, the top of the elastic member (7) is compressed and deformed and does not contact the worktable (3), the elastic member (7) includes an elastic ring (71), the cross-section of the elastic ring (71) is a U-shape with an opening downward, and the open end of the elastic ring is fixed to the groove surface of the annular groove (43) to form a closed interval space.

2. The air-floating lifting and rotating platform according to claim 1, characterized in that: A radial bearing (5) is provided inside the thrust bearing (4), the loading platform (3) and the inner side clearance of the radial bearing (5) are matched to form a cavity, and the loading platform (3) is connected to a motor (6).

3. The air-floating lifting and rotating platform according to claim 1, characterized in that: The second air supply hole (42) is annular.

4. The air-floating lifting and rotating platform according to claim 1, characterized in that: The radial cross-sectional width of the annular groove (43) is greater than the radial cross-sectional width of the second air supply hole (42).

5. The air-floating lifting and rotating platform according to claim 2, characterized in that: The loading platform (3) includes a spacer (31), an upper plate (32) and a lower plate (33), wherein the spacer (31) is arranged on the inner side of the radial bearing (5), the upper plate (32) is arranged on the upper part of the spacer (31) and is connected to the motor (6), and the lower plate (33) is arranged on the lower part of the thrust bearing (4), the upper plate (32) and the upper surface of the thrust bearing (4) are in clearance fit, the lower plate (33) and the lower surface of the thrust bearing (4) are in clearance fit, and the spacer (31) and the inner side of the radial bearing (5) are in clearance fit.

6. The air-floating lifting and rotating platform according to claim 5, characterized in that: The side surface of the radial bearing (5) is uniformly distributed with rotation guide holes (51) along the circumferential direction. The rotation guide holes (51) are connected to the second air supply hole (42). The rotation guide holes (51) are inclined at the same angle as the rotation direction of the stage (3), thereby achieving reduced rotation resistance and uniform pressure distribution.

7. The air-floating lifting and rotating platform according to claim 6, characterized in that: A rotation guide groove (311) is provided on the outer periphery of the spacer (31), the rotation guide groove (311) and the rotation guide hole (51) are arranged in a position corresponding to each other, and the extension direction of the rotation guide groove (311) and the rotation guide hole (51) are consistent.

8. The air-floating lifting and rotating platform according to claim 1, characterized in that: The bottom of the loading platform (3) is rotatably connected to a rotating shell (22), and the rotating shell (22) is spaced apart inside the housing (21).

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