Air floatation lifting rotating platform comprising lifting mechanism capable of continuously rotating

Abstract

The invention belongs to the field of semiconductor manufacturing equipment, and particularly relates to an air floatation lifting rotating platform with a lifting mechanism capable of continuously rotating. The platform integrates a rotating mechanism and a lifting mechanism, the rotating mechanism achieves friction-free rotation through an air floating bearing, and the lifting mechanism drives an air floating shaft to accurately ascend and descend on a linear guide rail through a first voice coil motor. And rotation and lifting motion are separated through the air bearing, motion decoupling is achieved, and internal cable winding is avoided. The platform adopts a grading driving strategy of air cylinder pre-jacking and second voice coil motor fine adjustment, has both high-speed response and micron-level positioning precision, is suitable for precise scanning scenes needing synchronous rotating and lifting in wafer detection, and effectively improves the detection efficiency and reliability.

Description

Technical Field

[0001] The invention belongs to the field of semiconductor manufacturing equipment, and in particular relates to an air-floating lifting and rotating platform comprising a continuously rotating lifting mechanism. Background Art

[0002] In semiconductor wafer optical inspection equipment, many devices have been produced for wafer inspection to achieve efficient and precise scanning of the wafer surface, such as the disclosed technology CN114111691A. Wafer rotation and axial lifting motion need to be synchronously controlled during wafer scanning inspection. Traditional technical solutions usually adopt a split-structure design with a rotary motor and a lifting cylinder or a lead screw. This results in a bulky device, delayed motion response, and difficulty in achieving complex trajectory motions such as spiral scanning. More importantly, the split structure faces the risk of fatigue fracture caused by repeated torsion of the rotating component cables during long-term operation, seriously affecting the reliability of the equipment.

[0003] Existing integrated solutions attempt to couple rotation and lift functions through mechanical bearings. However, bearing friction torque can cause rotational jitter, degrading wafer imaging quality. Furthermore, mechanical friction during the lift process exacerbates wear on the motion mechanism, making it difficult to maintain micron-level positioning accuracy over the long term. While air bearing technology can address rotational friction, integrated lift-rotation platforms still lack an effective motion decoupling mechanism, making it impossible to achieve the coordinated control of high-precision rotation and high-response lift.

[0004] The current technical bottlenecks are mainly manifested in the following aspects: the cylinder drive has creeping phenomenon and hysteresis nonlinearity, which makes it difficult to meet the dual requirements of millisecond-level response and precise positioning; and the mechanical coupling interference of the rotation and lifting compound motion further restricts the development of high-end wafer detection equipment towards high speed and high precision. Summary of the Invention

[0005] The present invention provides an integrated platform integrating an air bearing and a voice coil motor, which realizes frictionless continuous rotation and high-precision lifting and lowering synchronously through dynamic decoupling technology, and completely solves the problems of motion interference and cable entanglement in semiconductor wafer inspection.

[0006] An air-floating lifting and rotating platform with a continuously rotating lifting mechanism comprises a rotating mechanism and a lifting mechanism. The lifting mechanism includes a voice coil motor and a linear guide. The rotating mechanism includes an air-floating shaft and a rotating platform. The rotating motor is mounted on the outer periphery of the air-floating shaft, and the voice coil motor is mounted on the bottom. The air-floating shaft is mounted on the linear guide via an air bearing. The air bearing comprises an inner bearing ring and an outer bearing ring. The voice coil motor drives the air-floating shaft and the air-floating bearing to move vertically on the linear guide. When the air-floating bearing is ventilated, the rotating motor drives the air-floating shaft and the inner bearing ring to rotate about the axis of the air-floating shaft. This device is used in wafer inspection. During the inspection process, wafers must be lifted and rotated to facilitate scanning by the inspection mechanism. This device combines the lifting and rotating mechanisms to drive the wafer suction cup for rotational lifting motion. This provides a core mechanism that integrates lifting and rotating functions, aiming to solve the problem of requiring separate lifting and rotation movements during wafer inspection. Its core purpose is to achieve high-precision, low-friction rotation through the air bearing and fast, precise linear lifting and lowering through the voice coil motor, effectively combining the two motions. This air-floating lifting and rotating platform combines lifting and rotation functions into a compact platform, simplifying the equipment structure and reducing the space occupied. Air bearings are used to support rotation, achieving non-contact, frictionless rotational motion, ensuring extremely high rotational accuracy and smoothness, and avoiding mechanical wear and vibration. Operators use voice coil motors for direct drive, providing high-acceleration, high-precision linear displacement, and fast response speed. This device uses air bearings to minimize interference between rotational motion and lifting motion (motion decoupling), allowing for independent or simultaneous high-precision rotation and lifting movements to meet the needs of complex detection paths. Because the drive device inside the rotary lifting platform requires many lines to connect, if ordinary platforms cannot decouple rotational motion and lifting motion, large-angle rotation will not be possible during rotational motion, otherwise it will cause entanglement of internal wiring. This device solves this problem.

[0007] An air-floating lifting and rotating platform with a continuously rotating lifting mechanism. A voice coil motor (VCM) is mounted inside a slider, which is slidably connected to a guide block. Several VCMs (VCMs) are located at the base of the guide block, driving the slider's vertical movement. The sliding connection between the slider and the guide block provides more stable and precise guidance for lifting and lowering, preventing lateral deviation and shaking. Multiple VCMs (VCMs) are installed to move the slider, the entire rotating mechanism, and the lifting mechanism within it to a designated position for operation. These VCMs collectively provide greater driving force to support heavier loads.

[0008] An air-floating lifting and rotating platform with a continuously rotating lifting mechanism features a cylinder mounted on the side of a guide block. The cylinder drive rod connects to the bottom of a carrier platform, which can be used to support a wafer suction cup. To integrate and position wafer equipment (such as the carrier platform and pre-processing module) on the platform, an auxiliary drive method is provided to adjust its horizontal or initial height. The carrier platform is heavy. If the entire load were supported by multiple second-level voice coil motors at the bottom, the load pressure on the second-level voice coil motors would be high. Therefore, the cylinder can initially push the carrier platform out a certain distance, after which the second-level voice coil motor drives the internal slider to move. This reduces the initial load on the second-level voice coil motor. While the second-level voice coil motor drives the slider to move, the cylinder can also adjust the support force, allowing for quick adjustment of the carrier platform's height or horizontal position.

[0009] An air-floating lifting and rotating platform with a continuously rotating lifting mechanism. The slider has a central through-hole, into which the lifting mechanism base is mounted. A plum blossom hole is also located in the center of the lifting mechanism base, into which the voice coil motor (VCM) is mounted. The bottom of the slider is threadedly connected to the top surface of the lifting mechanism base, which is then threaded onto the bottom surface of the lifting mechanism base. This threaded connection ensures that the VCM and the lifting mechanism base are securely fixed within the slider, preventing loosening or displacement during high-speed movement or load fluctuations, thereby ensuring transmission rigidity and reliability.

[0010] This air-floating lifting and rotating platform includes a continuously rotating lifting mechanism. The lifting mechanism's base is provided with an internal edge, and the rotating motor is mounted on this edge. Mounting the rotating motor above the edge of the lifting mechanism's base centralizes the driving sources for lifting and rotating, reducing the overall structure's volume and complexity, making the layout more rational, and saving longitudinal space.

[0011] An air-floating lifting and rotating platform with a continuously rotating lifting mechanism is described. The top periphery of the air-floating shaft is provided with multiple raised portions, and the rotating platform is internally provided with mating grooves that mate with the raised portions. The raised portions and the mating grooves cooperate with each other, enabling the air-floating shaft to drive the rotating platform to rotate. This structure provides an efficient and reliable power transmission connection between the rotating platform and the air-floating shaft, ensuring that the rotational motion can be transmitted to the load without loss. The meshing structure of the raised portions and the mating grooves can transmit a large torque, prevent slippage, and ensure that the rotating platform and the air-floating shaft rotate synchronously. This connection method allows relative axial movement between the air-floating shaft and the rotating platform while transmitting circumferential torque, thus perfectly meeting the requirements of lifting motion.

[0012] This air-floating lifting and rotating platform features a continuously rotating lifting mechanism. The top of the air-floating shaft is equipped with a rod for insertion into a wafer receptacle. This interface allows for quick and precise alignment and connection between a wafer chuck (or similar load) and the air-floating shaft. Inserting the rod into the wafer receptacle ensures precise alignment between the upper wafer chuck and the air-floating shaft, ensuring the center of rotation aligns with the center of the chuck, thus avoiding vibration or measurement errors caused by eccentricity.

[0013] An air-floating lifting and rotating platform with a continuously rotating lifting mechanism. It also includes a control unit, a position sensor, and an acceleration sensor; The control unit is configured to execute a lifting motion control method, including: Calculate the position error based on the target position and the actual position fed back by the position sensor; When the position error is greater than the first set threshold, the cylinder is mainly driven to move so that the slider quickly approaches the target position; When the position error is less than or equal to the first set threshold, the second voice coil motor is mainly driven to move, while the cylinder is controlled to maintain a constant support force or lock the position, so that the slider is accurately positioned to the target position; During the primary drive phase for the second voice coil motor, the control unit calculates and outputs control commands to it in real time based on position error, achieving high-precision positioning or vibration suppression for the slider. By setting a position error threshold, the cylinder is prioritized for long-distance movement (coarse adjustment phase), achieving fast response and large-stroke motion, shortening positioning time. When approaching the target position, the control unit switches to the second voice coil motor for micron-level fine adjustment. This overcomes the inherent nonlinear friction and creep issues of the cylinder, balancing the high speed of the cylinder with the high precision of the voice coil motor, and breaking through the performance limitations of a single actuator. During the coarse adjustment phase, the voice coil motor can be disabled or operated at low power, with the cylinder providing the primary driving force. The voice coil motor is activated only during the fine adjustment phase, reducing heat generation caused by long-term operation, improving system reliability, and extending service life. During the fine adjustment phase, the high-bandwidth control of the voice coil motor suppresses residual vibration in real time, preventing low-speed cylinder jitter from affecting positioning stability. This provides a stable lifting reference for applications such as high-precision inspection and micro-assembly.

[0014] The invention discloses an air-floating lifting and rotating platform including a continuously rotating lifting mechanism. An acceleration sensor and a position sensor are installed on the bearing platform.

[0015] An air-floating lifting and rotating platform with a continuously rotating lifting mechanism. The control unit is further configured to: Receive vibration signals from an acceleration sensor mounted on a slider or a carrier platform; Based on the vibration signal, the suppression force command for counteracting the vibration is calculated in real time; Outputting a damping force command to the second voice coil motor to drive the second voice coil motor to generate an active damping force with a phase opposite to the detected vibration; The active damping force calculation is based on at least one of the following algorithms: PID control, adaptive filtering, least mean square algorithm or model predictive control.

[0016] Accelerometers capture vibration signals (such as cylinder start-stop impact, coupled vibrations from rotating mechanisms, and external environmental disturbances) in real time, allowing the voice coil motor to generate a reverse active damping force. This extends the voice coil motor from a positioning actuator to a dynamic vibration absorber, achieving multifunctional integration. Traditional passive dampers are unable to adaptively suppress broadband vibrations (such as low-frequency cylinder jitter and high-frequency motor harmonics). This solution uses an algorithm to dynamically adjust the damping force spectrum characteristics.

[0017] The advantages of this invention lie in its organic integration of zero-friction rotation through an air bearing and precise lift and lowering of a voice coil motor, completely eliminating motion coupling interference and cable entanglement. Its core advantage lies in simultaneously achieving high dynamic performance and an extremely long service life. Millisecond-level response lift and high-precision rotation can operate simultaneously, and the contactless motion mechanism avoids mechanical wear. The compact integrated design, combined with a two-stage drive strategy for coarse cylinder adjustment and fine voice coil adjustment, significantly reduces the device size while maintaining micron-level positioning capabilities and high-speed lift and lowering, significantly improving the efficiency and reliability of semiconductor wafer inspection. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for the embodiments or the description of the prior art. Obviously, the drawings described below are merely exemplary, and those skilled in the art can derive other implementation drawings based on the provided drawings without inventive effort.

[0019] Figure 1 This is a schematic diagram of the overall device of the present invention; Figure 2 This is an exploded view of the overall device of the present invention; Figure 3 Schematic diagram of the rotating mechanism and lifting mechanism of the present invention; Figure 4 Schematic diagram of the air-floating shaft and rotating platform of the present invention; Figure 5 This is a schematic diagram of the bottom of the guide block of the present invention; Figure 6 This is a schematic diagram of the bottom of the slider of the present invention; Figure 7 It is a schematic diagram of the slider of the present invention; Figure 8 This is a schematic diagram of the base of the lifting mechanism of the present invention; Figure 9 This is a schematic diagram of the lifting mechanism base and the rotating motor of the present invention; Figure 10 This is an exploded view of the slider, lifting mechanism, rotating motor, and rotating mechanism of the present invention; Figure 11 This is an exploded view of the slider, rotating motor, and rotating mechanism of the present invention; Figure 12 It is a cross-sectional view of the overall device of the present invention; Figure 13 This is a flow chart of Example 2 of the present invention; Figure 14 This is a flow chart of Example 3 of the present invention.

[0020] Description of the drawings: 1-rotating mechanism, 2-lifting mechanism, 3-air bearing, 3a-bearing inner ring, 3b-bearing outer ring, 4-slider, 5-guide block, 6-rotating motor, 7-carrying platform, 11-air bearing shaft, 12-rotating platform, 21-voice coil motor No. 1, 21a-gap, 22-linear guide rail, 41-through hole, 43-lifting mechanism base, 43a-plum blossom hole, 43b-edge, 51-voice coil motor No. 2, 52-cylinder, 11a-protrusion, 12a-matching groove, 11b-extending rod. DETAILED DESCRIPTION

[0021] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. 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.

[0022] The following first describes the concepts involved in this application with reference to the accompanying drawings. It should be noted that the following description of each concept is intended only to make the content of this application easier to understand and does not limit the scope of protection of this application. At the same time, the embodiments and features in the embodiments of this application can be combined with each other unless there is a conflict. The following detailed description of this application will be made with reference to the accompanying drawings and in conjunction with the embodiments.

[0023] Example 1: Refer to the attached Figure 1 , Attachment Figure 12 As shown, this embodiment describes an air-floating, lifting, and rotating platform for use in wafer optical appearance inspection equipment. The air-floating, lifting, and rotating platform is secured to the inspection equipment frame via a guide block 5 at its base. A carrier 7 is mounted above the guide block 5 via a drive rod of an air cylinder 52. A wafer suction cup is mounted on the carrier 7 for supporting and vacuum-absorbing the wafer to be inspected. A wafer insertion hole is defined at the bottom of the wafer suction cup.

[0024] Refer to the attached Figure 3 , Attachment Figure 5 , Attachment Figure 6 , Attachment Figure 8 , Attachment Figure 9 , Attachment Figure 12 As shown, the first voice coil motor 21 of the lifting mechanism 2 and the rotary motor 6 of the rotary mechanism 1 are both connected to an external multi-axis motion controller via cables. The air bearing 3 is connected to an external clean compressed air source via an air pipe. The air supply is equipped with a precision filter and a pressure regulating valve. The air pipe can extend through the gap 21a between the bottom of the first voice coil motor 21 and the lifting mechanism base 43.

[0025] Refer to the attached Figure 2 , Attachment Figure 5 , Attachment Figure 6 , Attachment Figure 7 , Attachment Figure 12 As shown, in the initial state, the air bearing 3 is not ventilated, the drive rod of the cylinder 52 is retracted, and the carrier 7 and wafer chuck are in a lower position. The entire lifting and rotating mechanism is driven by the four No. 2 voice coil motors 51 at the bottom, which are stopped at the lower limit of their travel. The operator first activates the cylinder 52, extending its drive rod and lifting the carrier 7 and wafer chuck upward a predetermined distance. This operation is intended to pre-emptively assume the majority of the weight of the wafer chuck, significantly reducing the load on the No. 2 voice coil motor 51 during subsequent operations. The controller then activates the No. 2 voice coil motor 51, and its output shaft pushes against the slider 4, causing it to rise smoothly along the guide block 5. Because the cylinder 52 already bears the majority of the weight, the No. 2 voice coil motor 51 only needs to apply a small amount of force to achieve precise activation and positioning, raising the entire internal lifting mechanism 2 and rotating mechanism 1 to the starting height.

[0026] Refer to the attached Figure 3 , Attachment Figure 4 , Attachment Figure 12 As shown, after reaching the starting height, an external clean compressed air source supplies air to the air bearing 3. The high-pressure gas forms an extremely thin air film between the bearing inner ring 3a and the bearing outer ring 3b, levitating the air bearing shaft 11 and its connected components, achieving a completely non-contact, zero-friction support state. The operator controls the voice coil motor 21, which generates electromagnetic force and directly drives the air bearing shaft 11 for precise vertical movement along the linear guide 22. The high response characteristics of the voice coil motor 21 enable the wafer chuck to be quickly and accurately positioned to different inspection focal length planes.

[0027] Refer to the attached Figure 3 , Attachment Figure 4 , Attachment Figure 10 , Attachment Figure 11 , Attachment Figure 12As shown, the rotary motor 6 then starts to work, and the rotor of the rotary motor 6 drives the air-floating shaft 11 and the bearing inner ring 3a to rotate continuously around the axis of the air-floating shaft 11. The rotational power is transmitted to the rotating platform 12 without loss through the engagement of the multiple protrusions 11a on the top of the air-floating shaft 11 with the matching grooves 12a inside the rotating platform 12. The extension rod 11b of the rotating platform 12 is inserted into the socket of the wafer suction cup, ensuring that the rotation center is strictly aligned with the center of the wafer, thereby driving the wafer suction cup and the wafer adsorbed thereon to rotate smoothly and without eccentricity, facilitating the scanning and inspection of the wafer by the inspection equipment.

[0028] During this process, lifting and lowering motion are completely decoupled from rotational motion. The air-bearing shaft 11 can perform lifting and lowering motions without interference while rotating. This enables the inspection equipment's scanning head to perform spiral or specified path scanning on the rotating wafer, greatly improving inspection efficiency. All cables leading to the voice coil motor 21 and the rotary motor 6 are fixed to the slider 4 and rise and fall with the entire internal mechanism, rather than rotating with the air-bearing shaft 11, thus completely avoiding the wire entanglement problem common in traditional rotating platforms.

[0029] After the test is complete, the rotary motor 6 stops, the air bearing 3 stops venting, and the bearing inner race 3a falls back to contact the bearing outer race 3b. Voice coil motor 21 then drives the air bearing shaft 11 down to its initial position. Subsequently, voice coil motor 51 drives the slider 4 downward, and finally, cylinder 52 retracts the rod, returning the support platform 7 to its initial position, completing one operating cycle.

[0030] This embodiment fully demonstrates how the present invention seamlessly combines high-precision lifting and high-speed rotation. The air bearing achieves high rotational stability and an extremely long lifespan, while the voice coil motor achieves rapid and high-precision lifting. The unique "cylinder pre-lift and voice coil motor precision positioning" dual-stage structure and the use of air bearings successfully achieve motion decoupling, avoiding cable entanglement and ultimately meeting the stringent requirements of modern wafer inspection equipment for high efficiency, high precision, and high reliability.

[0031] Example 2: A high-resolution linear scale is installed near the slider 4 or linear guide 22 as a position sensor. This measures the slider's precise position in real time and provides feedback to the control unit (which can use a high-performance industrial PC or motion controller). The cylinder 52 is an electrically controlled cylinder with a servo proportional valve, enabling precise control of its speed, position, and output force. The second voice coil motor 51 is equipped with a high-performance driver.

[0032] Refer to the attached Figure 13As shown, during the coarse adjustment phase, the control unit sets the target position to T, the first threshold to T1, and reads the actual position T2 fed back by the scale. The error is calculated as E = T - T2. If E > T1, the control unit sends a command to the servo proportional valve of cylinder 52, driving cylinder 52 to rapidly push the support platform 7, which in turn drives the slider 4 toward the target position. At this point, the control unit sends a very small constant current command to voice coil motor number 2 51, causing its output force to overcome its own static friction and follow the slider's movement. Furthermore, after the coarse adjustment phase, ensure that E is a positive number (i.e., after the coarse adjustment phase, the actual position T2 is below the target position T).

[0033] During the fine-tuning phase, the control unit primarily calculates the voice coil motor drive command. It sets a constant air pressure command to the servo proportional valve, causing cylinder 52 to output a stable supporting force (supporting most of the weight of platform 7). The air paths on both sides of cylinder 52 are closed, and the internal air pressure of cylinder 52 locks the piston position (if permitted by the cylinder design). Based on the small error E, the control unit uses a high-gain PID controller or other precise positioning algorithm to calculate the force command F1 for voice coil motor 51 number two. This F1 command is sent to the driver of voice coil motor 51 number two, driving it to precisely move slider 4 to position T. The high response characteristics of voice coil motor 51 number two enable it to quickly eliminate small errors and suppress residual vibration. Position feedback is continuously read, and the coarse and fine tuning phases are repeated until error E stabilizes within the allowable accuracy range.

[0034] This solution combines the fast, long-stroke motion of the pneumatic cylinder 52 with the ultra-high-precision positioning capabilities of the voice coil motor. While the coarse adjustment phase allows for rapid approach to the target, the fine adjustment phase utilizes the voice coil motor to achieve micron-level positioning accuracy and suppress vibration, significantly improving the overall speed, accuracy, and smoothness of the lifting motion. Furthermore, the voice coil motor's operating time is reduced during the coarse adjustment phase, reducing energy consumption and heat generation.

[0035] Example 3: Refer to the attached Figure 14 As shown, this embodiment describes in detail the superimposed implementation of active damping control on embodiment 2.

[0036] A high-bandwidth accelerometer is mounted on platform 7 to measure the vertical (Z-axis) vibration acceleration a1 in real time and feed it back to the control unit. The control unit reads the acceleration signal a. This signal can be filtered (e.g., using a low-pass filter to remove high-frequency noise). The control unit's goal is to generate a force F2 such that the acceleration a2 generated by F2 is equal in magnitude and opposite in direction to a1 (180 degrees out of phase), thereby canceling out the vibration. A simple and effective calculation method is: , , Kp, Ki, and Kd are the proportional, integral, and differential gain coefficients of the PID controller, which need to be adjusted based on the system model or on-site debugging. v1 is the instantaneous vibration velocity obtained by integrating the acceleration. U is the control signal command, which is output to the driver of the second voice coil motor 51. The millisecond-level response speed of the second voice coil motor 51 enables it to generate precise force F2 in real time. F2 is the required active damping force.

[0037] During the coarse adjustment phase, the active damping force F2 is generated by the second voice coil motor 51. This helps to suppress vibration caused by rapid start and stop of the cylinder 52 or external shock.

[0038] During the fine-tuning phase, the active damping force F2 is added to the precise positioning force command F1 for the second voice coil motor 51. This means the final force command for the voice coil motor is F3 = F1 + F2. This allows the voice coil motor to precisely position itself while simultaneously counteracting the vibrations generated by the platform's movement.

[0039] The introduction of active damping control based on acceleration feedback significantly improves platform stability during lifting and lowering motion (especially during start-stop moments) and after reaching the target position. This effectively suppresses platform jitter caused by actuator characteristics (such as cylinder 52 creep and thrust fluctuations in the second voice coil motor 51), load variations, and ground vibration, providing an extremely stable foundation for high-precision rotation, measurement, or operation. Voice coil motors are ideal actuators for achieving this high-speed, precise damping.

[0040] The embodiments and / or implementation methods described above are only used to illustrate the preferred embodiments and / or implementation methods for realizing the technology of the present invention, and do not impose any form of limitation on the implementation methods of the technology of the present invention. Any person skilled in the art may make slight changes to other equivalent embodiments without departing from the scope of the technical means disclosed in the content of the present invention, but they should still be regarded as technologies or embodiments that are essentially the same as the present invention.

[0041] This article uses specific examples to illustrate the principles and implementation methods of this application. The description of the above embodiments is only used to help understand the method and core ideas of this application. The above is only the preferred implementation method of this application. It should be pointed out that due to the limitations of textual expression, there are objectively infinite specific structures. For ordinary technicians in this technical field, without departing from the principles of this application, they can also make several improvements, modifications or changes, and can also combine the above technical features in an appropriate manner; these improvements, modifications, changes or combinations, or the direct application of the inventive concept and technical solution to other occasions without improvement, should be regarded as the scope of protection of this application.

Claims

1. An air-floating lifting and rotating platform with a continuously rotating lifting mechanism, characterized in that: The invention comprises a rotating mechanism (1) and a lifting mechanism (2), wherein the lifting mechanism (2) comprises a voice coil motor (21) and a linear guide rail (22), wherein the rotating mechanism (1) comprises an air-floating shaft (11) and a rotating platform (12), wherein a rotating motor (6) is installed on the periphery of the air-floating shaft (11), and a voice coil motor (21) is installed on the bottom thereof, wherein the air-floating shaft (11) is installed on the linear guide rail (22) via an air-floating bearing (3), wherein the air-floating bearing (3) is divided into a bearing inner ring (3a) and a bearing outer ring (3b), wherein the voice coil motor (21) drives the air-floating shaft (11) and the air-floating bearing (3) to move vertically on the linear guide rail (22), and when the air-floating bearing (3) is ventilated, the rotating motor (6) drives the air-floating shaft (11) and the bearing inner ring (3a) to rotate around the axis of the air-floating shaft (11).

2. The air-floating lifting and rotating platform with a continuously rotating lifting mechanism according to claim 1, characterized in that: The first voice coil motor (21) is installed inside the slider (4), the slider (4) is slidably connected to the guide block (5), and a plurality of second voice coil motors (51) are provided at the bottom of the guide block (5), and the second voice coil motors (51) are used to drive the slider (4) to move vertically.

3. The air-floating lifting and rotating platform with a continuously rotating lifting mechanism according to claim 2, characterized in that: A cylinder (52) is provided on the side of the guide block (5), and a drive rod of the cylinder (52) is connected to the bottom of the bearing platform (7).

4. The air-floating lifting and rotating platform with a continuously rotating lifting mechanism according to claim 3, characterized in that: It also includes a control unit, a position sensor, and an acceleration sensor; The control unit is configured to execute a lifting motion control method, including: Calculating a position error based on a target position and an actual position fed back by the position sensor; When the position error is greater than a first set threshold, the cylinder (52) is mainly driven to move, so that the slider (4) quickly approaches the target position; When the position error is less than or equal to the first set threshold, the second voice coil motor (51) is mainly driven to move, while the cylinder (52) is controlled to maintain a constant supporting force or a locked position, so that the slider (4) is accurately positioned to the target position; In the stage of mainly driving the second voice coil motor (51), the control unit calculates in real time based on the position error and outputs a control instruction to the second voice coil motor (51), thereby achieving high-precision positioning or vibration suppression of the slider (4).

5. The air-floating lifting and rotating platform with a continuously rotating lifting mechanism according to claim 4, characterized in that: The acceleration sensor and the position sensor are mounted on the bearing platform (7).

6. The air-floating lifting and rotating platform with a continuously rotating lifting mechanism according to claim 4, characterized in that: The control unit is further configured to: receiving a vibration signal from an acceleration sensor, wherein the acceleration sensor is mounted on the slider (4) or the supporting platform (7); Based on the vibration signal, calculating in real time a restraining force instruction for counteracting the vibration; Outputting the restraining force instruction to the second voice coil motor (51), driving the second voice coil motor (51) to generate an active damping force opposite to the detected vibration phase; Wherein, the active damping force calculation is based on a PID control algorithm.

7. The air-floating lifting and rotating platform with a continuously rotating lifting mechanism according to claim 2, characterized in that: The slider (4) is provided with a through hole (41) at its center, a lifting mechanism base (43) is installed in the through hole (41), a plum blossom hole (43a) is provided at its center, and the first voice coil motor (21) is installed in the plum blossom hole (43a).

8. The air-floating lifting and rotating platform with a continuously rotating lifting mechanism according to claim 7, characterized in that: An edge (43b) is provided inside the lifting mechanism base (43), and the rotating motor (6) is mounted on the edge (43b).

9. The air-floating lifting and rotating platform with a continuously rotating lifting mechanism according to claim 1, characterized in that: The top periphery of the air-floating shaft (11) is provided with a plurality of protrusions (11a), and the interior of the rotating platform (12) is provided with matching grooves (12a) that match the protrusions (11a). The protrusions (11a) and the matching grooves (12a) cooperate with each other, so that the air-floating shaft (11) can drive the rotating platform (12) to rotate.

10. The air-floating lifting and rotating platform with a continuously rotating lifting mechanism according to claim 1, characterized in that: The top of the air-floating shaft (11) is provided with a protruding rod (11b) for inserting into the socket of the wafer suction cup.

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