Quick response magnetic levitation micropositioner driven by PCB coil

Abstract

The invention relates to a quick-response magnetic levitation micropositioner driven by a PCB (Printed Circuit Board) coil, which aims to solve the problem that the traditional air floatation and mechanical workpiece stage is difficult to meet the requirement of extremely high positioning accuracy of the workpiece stage, and comprises a micropositioner base, an objective table, a gravity compensator assembly, a stator array, a PCB coil group and a limiting assembly, and the objective table and the micropositioner base are arranged from top to bottom; the objective table is connected with the micropositioner base through the limiting assembly, the gravity compensator assembly is installed between the micropositioner base and the objective table, the stator array is connected with the upper surface of the micropositioner base, and the PCB coil assembly is installed on the lower surface of the objective table. Compared with other micropositioner schemes, the complexity of a mechanical structure is reduced, and the overall weight of a micropositioner system is reduced, so that the load of the macro-positioner is reduced, the acceleration and the maximum speed of the macro-positioner are increased, the response speed of the system is improved, and the scheme has great significance in improving the productivity of a photoetching machine. The invention belongs to the technical field of precision motion tables.

Description

Technical Field

[0001] The present invention relates to a magnetic levitation micro-stage, and more particularly to a fast-response magnetic levitation micro-stage driven by a PCB coil. The present invention belongs to the technical field of precision motion stages. Background Art

[0002] With the rapid development of industries such as integrated circuits, there is an urgent need for ultra-high-precision processing equipment. However, ultra-high-precision processing equipment often requires a harsh processing environment. For example, in the field of chip processing, in order to break through the 7nm mark, EUV lithography machines have emerged, which require the lithography process to be completed in a high-vacuum and high-clean environment. Mechanical motion stages and air-bearing motion stages are difficult to meet the requirements. Therefore, a motion stage based on electromagnetic drive technology must be used to carry the wafer to complete the lithography task.

[0003] The lithography task requires the motion stage to meet the requirements of large stroke and high precision. Currently, a macro-micro combined design scheme is mainly adopted. First, the macro-stage is responsible for large-stroke motion and micron-level rough positioning. On this basis, the micro-stage is responsible for small-stroke nanometer-level positioning. Therefore, the positioning accuracy of the micro-stage determines the processing accuracy of the entire lithography machine. Early micro-stages basically adopted the technical route of piezoelectric drive. However, the piezoelectric sheet is in direct contact with the load. Over time, the friction between components will reduce the accuracy and damage the cleanliness, affecting the processing accuracy. To solve the problem of mechanical friction causing dust and reducing cleanliness, some researchers proposed a micro-stage system combining a planar motor and a gravity compensator. However, its mass and volume are too large, which will increase the driving current of the macro-stage, reduce the motion speed and response speed of the macro-stage, and reduce the efficiency. Secondly, the compensator itself has a certain height, which will make the vertical distance between the macro-stage and the micro-stage too large, and it is not easy to maintain stability during the motion process, resulting in the collapse of the system. Summary of the Invention

[0004] The present invention aims at the ultra-precision machining field, such as EUV lithography machines, which require the workpiece stage to have extremely high positioning accuracy. However, due to the requirements of high cleanliness and high vacuum in the processing environment, traditional air-bearing and mechanical workpiece stages are difficult to meet the needs. Therefore, a fast-response magnetic levitation micro-stage driven by a PCB coil is proposed.

[0005] The technical solutions adopted by the present invention to solve the above problems are as follows:

[0006] The stator part of the present invention consists of four groups of one-dimensional Halbach magnet arrays; the mover is composed of four groups of PCB coils; when the PCB coils are energized, an electromagnetic interaction is generated between the coils and the magnets to stabilize the suspension height of the micro stage. By adjusting the current phase and amplitude, six-degree-of-freedom movement of the micro stage can be achieved. Compared with other micro stage solutions, this method reduces the complexity of the mechanical structure, decreases the overall weight of the micro stage system, thereby reducing the load on the macro stage and increasing its acceleration and maximum speed, improving the response speed of the system. This solution is of great significance for increasing the production capacity of lithography machines. Specifically as follows:

[0007] The present invention includes a micro stage base, a stage, a gravity compensator assembly, a stator array, a PCB coil group, and a limit component. The stage and the micro stage base are arranged from top to bottom. The stage and the micro stage base are connected by the limit component. The gravity compensator assembly is installed between the micro stage base and the stage. The stator array is connected to the upper surface of the micro stage base, and the PCB coil group is installed on the lower surface of the stage.

[0008] Further, the gravity compensator assembly includes a gravity compensator and a gravity compensator tray. The gravity compensator is installed in the middle of the upper surface of the micro stage base, and the gravity compensator tray is installed in the middle of the lower surface of the stage. The gravity compensator and the gravity compensator tray are connected by screws.

[0009] Further, the gravity compensator includes a housing, an upper magnet, an upper magnet back plate, a middle magnet, a middle magnet fixing column, a middle magnet lower plate, a lower magnet, and a lower magnet back plate. The upper magnet, the middle magnet, and the lower magnet are arranged from top to bottom and are located inside the housing. The upper magnet is installed at the upper end of the housing through the upper magnet back plate. The middle magnet is installed in the middle of the housing through the middle magnet lower plate. The lower magnet is installed at the lower end of the housing through the lower magnet back plate. The lower end of the middle magnet fixing column is fixed to the middle magnet lower plate, and the upper end sequentially passes through the upper magnet and the upper magnet back plate.

[0010] Further, the number of the limit components is four. The four limit components are arranged in a rectangle. Each limit component includes a lower limit block, an upper limit block, and a limit stud. The upper limit block is installed on the lower surface of the stage, the lower limit block is installed on the upper surface of the micro stage base, and the upper limit block and the lower limit block are connected by the limit stud.

[0011] Further, the upper limit block includes a cylinder. A rectangular block is provided on the lower surface of the cylinder. A threaded hole communicating with the cylinder is provided on the rectangular block for cooperation with the limit stud. The lower limit block is composed of an upper cylinder and a lower cylinder connected. The diameter of the upper cylinder is smaller than that of the lower cylinder. A clamping groove for cooperation with the rectangular block is provided on the upper surface of the upper cylinder, and a threaded hole for cooperation with the limit stud is provided in the middle of the upper surface of the lower cylinder.

[0012] Further, the PCB coil groups are four in number and are respectively located inside the middle parts of the four straight edges on the lower surface of the stage. Each of the PCB coil groups is formed by stacking twenty layers of PCB coils together in sequence.

[0013] Further, the PCB coil groups are mounted on a coil backplane, and a water cooling pipe is provided between the coil backplane and the PCB coil groups.

[0014] Further, the stator arrays are four in number and are respectively located inside the middle parts of the four straight edges on the upper surface of the micro-stage base.

[0015] Further, an X-direction eddy current sensor, a Z-direction eddy current sensor, and a Y-direction eddy current sensor are provided on the upper surface of the micro-stage base, and an eddy current sensor reflector is provided on the lower surface of the stage.

[0016] The beneficial effects of the present invention are as follows:

[0017] 1. The present invention uses the method of stacking multiple groups of PCB coils to replace traditional coils for driving. Since the shapes of the PCB coils are regular, stray forces and torques can be reduced, external disturbances can be reduced, the stability and positioning accuracy of the micro-stage can be improved, and due to the smaller inductance and resistance, the response speed and bandwidth of the micro-stage can be increased, the phase lag under high-frequency drive signals can be improved, and the stability of the magnetic levitation motion stage can be improved.

[0018] 2. The present invention uses a gravity compensator to offset most of the load, reduce the levitation static current, increase the horizontal drive current, improve the ultimate jerk, acceleration, and speed, reduce the burden on the driver, and reduce coil heating.

[0019] 3. The small mass of the PCB coils in the present invention can reduce the load on the macro-stage and improve the response speed of the macro-stage. The magnetic levitation micro-stage based on PCB drive technology has guiding significance for the macro-micro combined magnetic levitation motion stage and has great significance for the development of workpiece stage technology in the ultra-precision manufacturing field. Description of the Drawings

[0020] Figure 1 is a perspective view of the overall structure of the present invention;

[0021] Figure 2 is a schematic diagram of the overall structure of the present invention;

[0022] Figure 3 is a schematic diagram of the connection of each component to the micro-stage base;

[0023] Figure 4 is a schematic diagram of the connection of each component to the stage;

[0024] Figure 5 is a schematic diagram of the structure of the gravity compensator;

[0025] Figure 6 is Figure 5 a sectional view of;

[0026] Figure 7 is a schematic diagram of the magnetization direction of the magnetic ring of the gravity compensator;

[0027] Figure 8 is a schematic diagram of the tray structure of the gravity compensator;

[0028] Figure 9 is a schematic diagram of the structure of the limiting component;

[0029] Figure 10 is a schematic diagram of the structure of the lower limiting block;

[0030] Figure 11 is a schematic diagram of the structure of the upper limiting block;

[0031] Figure 12 is a schematic diagram of the principle of the limiting component;

[0032] Figure 13 is a schematic diagram of the installation of the PCB coil;

[0033] Figure 14 is a schematic diagram of the structure of the water-cooling pipe;

[0034] Figure 15 is a schematic diagram of the structure of the stator array;

[0035] Figure 16 is a schematic diagram of the magnetization direction of the stator array;

[0036] Figure 17 is a schematic diagram of the measurement and driving scheme of the sixth specific implementation manner. Specific implementation manner

[0037] Specific implementation manner one: With reference to Figures 1 to 4 description, the fast-response magnetic levitation micro-stage driven by a PCB coil described in this implementation manner includes a micro-stage base 1, a load platform 2, a gravity compensator assembly 3, a stator array 4, a PCB coil group 5, and a limiting component 6. The load platform 2 and the micro-stage base 1 are arranged from top to bottom. The load platform 2 and the micro-stage base 1 are connected through the limiting component 6. The gravity compensator assembly 3 is installed between the micro-stage base 1 and the load platform. The stator array 4 is connected to the upper surface of the micro-stage base 1 by countersunk head screws. The PCB coil group 5 is installed on the lower surface of the load platform 2.

[0038] Specific implementation manner two: With reference to Figures 5 to 8Describing this embodiment, the gravity compensator assembly 3 includes a gravity compensator and a gravity compensator tray 3-2. The gravity compensator is installed in a circular groove in the middle of the upper surface of the micro-stage base 1 and is connected by screws. The gravity compensator tray 3-2 is installed in the middle of the lower surface of the stage 2. The gravity compensator and the gravity compensator tray 3-2 are connected by countersunk head screws. As shown in the figure, the function of the gravity compensator tray 3-2 is to connect the gravity compensator to the stage 2 and conduct the upward permanent magnetic force generated by the gravity compensator to the stage to offset the gravity of the stage. It has six countersunk through holes on its surface for connection with the stage 2, and a countersunk threaded hole in the center for connection with the gravity compensator.

[0039] The gravity compensator includes a housing 3-1, an upper magnet 3-2, an upper magnet back plate 3-3, a middle magnet 3-4, a middle magnet fixing column 3-5, a middle magnet lower plate 3-6, a lower magnet 3-7, and a lower magnet back plate 3-8. The upper magnet 3-2, the middle magnet 3-4, and the lower magnet 3-7 are arranged from top to bottom and are located inside the housing 3-1. The upper magnet 3-2 is installed at the upper end of the housing 3-1 through the upper magnet back plate 3-3. The middle magnet 3-4 is installed in the middle of the housing 3-1 through the middle magnet lower plate 3-6. The lower magnet 3-7 is installed at the lower end of the housing 3-1 through the lower magnet back plate 3-8. The lower end of the middle magnet fixing column 3-5 is fixed to the middle magnet lower plate 3-6, and the upper end sequentially passes through the upper magnet 3-2 and the upper magnet back plate 3-3.

[0040] The material of the upper magnetic backplane 3-3 is soft electrical iron, which has an external thread that can be mated with the internal thread of the upper part of the housing. There are two opposite threaded holes above the upper magnetic backplane 3-3, which are convenient for screwing in bolts to rotate the upper magnetic backplane 3-3 to adjust the distance between the upper magnet 3-2 and the lower magnet 3-7. The magnetic field strength between the upper magnet 3-2 and the lower magnet 3-7 is negatively correlated with the distance between the upper magnet 3-2 and the lower magnet 3-7. The closer the distance, the greater the magnetic field strength, and the greater the force on the middle magnet 3-4. Below the upper magnetic backplane 3-3, there is a circular groove slightly larger in diameter than the upper magnet 3-2, which is convenient for the installation and positioning of the upper magnet 3-2. The upper magnet 3-2, the middle magnet 3-4, and the lower magnet 3-7 are all cylindrical magnets with a circular through-hole in the center. Among them, the pole arrangements of the upper magnet 3-2 and the middle magnet 3-4 are different, providing an upward attraction force, and the pole arrangements of the middle magnet 3-4 and the lower magnet 3-7 are the same, providing an upward repulsive force. The outer diameters and inner diameters of the upper magnet 3-2 and the lower magnet 3-7 are the same. The outer diameter of the middle magnet 3-4 is x mm smaller than that of the upper magnet 3-2, and the inner diameter is x mm larger than the inner diameter of the upper magnet 3-2. This design can ensure that the middle magnet 3-4 moves within a uniform magnetic field within the horizontal range of x mm, ensuring the stability of the upward thrust. The material of the fixing column of the middle magnet 3-4 is acetal, and the overall shape is a cylindrical component that is thinner at the top and thicker at the bottom. There is a threaded hole on the upper end face, which is convenient for connection and fixation. The upper and lower connection parts are transitioned with a smooth curved surface to prevent damage to the upper magnet 3-2. There are four threaded holes below for fixing with the lower plate of the middle magnet. The material of the lower plate of the middle magnet is soft electrical iron, and the upper surface has a circular groove slightly larger in diameter than the outer diameter of the middle magnet 3-4, which is convenient for the installation and positioning of the middle magnet 3-4. And there are countersunk through-holes, which are fixed with countersunk head screws to ensure that the lower surface and the lower magnet 3-7 can be completely fitted, and the lower magnet 3-7 will not be damaged by the protruding screws. The upper half of the housing 3-1 is provided with an internal thread, which can be screwed together with the upper magnetic backplane 3-3. There are four threaded holes designed at the lower end, which can be connected with the lower magnetic backplane 3-8 with countersunk head screws. The upper surface of the lower magnetic backplane 3-8 has a circular groove slightly larger in diameter than the outer diameter of the lower magnet 3-7, which is convenient for the installation and positioning of the lower magnet 3-7. The lower surface is designed with countersunk through-holes, which are fixed with countersunk head screws to ensure that the lower surface and the micro-stage can be completely fitted.

[0041] The gravity compensator is composed of three magnetic rings, the upper magnet 3-2, the middle magnet 3-4, and the lower magnet 3-7. The magnetization directions are as Figure 7As shown, the magnetization directions of the upper magnet 3-2 and the middle magnet 3-4 are the same, while the magnetization direction of the middle magnet 3-4 is opposite to that of the lower magnet 3-7. The upper magnet 3-2 has an upward attractive force on the middle magnet 3-4, and the lower magnet 3-7 has an upward repulsive force on the middle magnet 3-4. Moreover, the outer diameter of the middle magnet 3-4 is smaller than those of the upper magnet 3-2 and the lower magnet 3-7. This ensures that when the microstage moves horizontally, the middle magnet 3-4 is always in a uniform magnetic field and can prevent the middle magnet 3-4 from being attracted to the housing 3-1, thus ensuring the stability of the output force and that the output point is always located at the center of the gravity compensator in the natural state. By rotating the upper magnet 3-2, the distance between the upper magnet 3-2 and the lower magnet 3-7 can be adjusted, thereby adjusting the output force and working position of the gravity compensator.

[0042] Specific Embodiment 3: Combining Figures 9 to 12 This embodiment will be described. The number of the limiting components 6 is four, and the four limiting components 6 are arranged in a rectangle. Each limiting component includes a lower limiting block 6-1, an upper limiting block 6-2, and a limiting stud 6-3. The upper limiting block 6-2 is installed on the lower surface of the load platform 2, the lower limiting block 6-1 is installed on the upper surface of the microstage base 1, and the upper limiting block 6-2 and the lower limiting block 6-1 are connected by the limiting stud 6-3.

[0043] Preferably, the upper limiting block includes a cylinder, a rectangular block is provided on the lower surface of the cylinder, and a threaded hole penetrating the cylinder is provided on the rectangular block for cooperating with the limiting stud; the lower limiting block is connected by an upper cylinder and a lower cylinder. The diameter of the upper cylinder is smaller than that of the lower cylinder. A clamping groove for cooperating with the rectangular block is provided on the upper surface of the upper cylinder, and a threaded hole for cooperating with the limiting stud is provided in the middle of the upper surface of the lower cylinder. The clamping groove cooperates with the rectangular block to rotate, and the lower end of the limiting stud sequentially passes through the threaded holes of the upper limiting block and the lower limiting block.

[0044] Preferably, the outer diameter of the lower cylinder of the lower limiting block is smaller than the diameter of the circular groove of the load platform 2, the outer diameter of the upper cylinder is smaller than the diameter of the circular through hole of the load platform, and the height of the upper cylinder is greater than the thickness of the lower wall of the circular groove of the load platform. Since the upper limiting block and the lower limiting block can be coupled to each other, and the height of the coupled part is greater than the thickness of the lower wall of the circular groove of the load platform 2, the microstage base can move up and down between the upper and lower limiting coupling parts. Since the diameter of the coupled part is smaller than the diameter of the circular groove, the horizontal movement of the microstage can be limited.

[0045] Specific Embodiment 4: Combining Figures 13 to 14In this embodiment, there are four groups of PCB coil sets 5, which are respectively located inside the middle parts of the four straight edges on the lower surface of the stage 2. The lower surface of the stage 2 is provided with a rectangular groove for PCB coil positioning, which is convenient for the positioning and installation of the PCB coil. Each PCB coil set is formed by stacking twenty layers of PCB coils together in sequence. The PCB coil set 5 is installed on the coil backplane 5-1, and a water-cooling pipe 5-2 is arranged between the coil backplane 5-1 and the PCB coil set 5. The lower surface of the stage 2 is provided with a rectangular groove for PCB coil positioning, which is for the positioning and installation of the PCB coil.

[0046] The PCB coil adopts a multi-layer stacking method to reduce the mass of the micro-stage and improve the thrust coefficient. In addition, by reasonably designing the vias and traces, the inductance and resistance of the coil can be reduced. Compared with the racetrack-shaped coil, the inductance and resistance of the PCB coil are greatly reduced, which can improve the bandwidth of the micro-stage system. An electromagnetic shielding layer is installed below the magnet to play an electromagnetic shielding role and prevent the magnetic field below the magnet from interacting with the magnetic field of the macro-stage. The water-cooling pipe is located inside the mover housing, and it adopts the shape of a serpentine pipe, which can increase the cooling area of the coil and enhance the cooling effect. The water-cooling system is located inside the mover housing, and it adopts the shape of a serpentine pipe, which can increase the cooling area of the coil. The inner diameter of the water-cooling pipe is 0.4 mm.

[0047] To reduce the mass of the micro-stage, the driving coil is selected as the PCB coil. The PCB coil has a light mass, a large effective area, and good heat dissipation. In this embodiment, the form of stacking 20 layers of PCB coils is adopted to improve the thrust coefficient. In a single-period magnet array, two-phase coils are used, and the phase difference of the energizing currents of the two coils is π / 2. The magnet and the coil will generate electromagnetic forces in the vertical direction and the horizontal direction (along the long side direction of the magnet). The acting force in the vertical direction can offset the gravity of the micro-stage and make it levitate, and the acting force in the horizontal direction can drive the micro-stage to move. There are four periods in a group of magnets, so there are 8 PCB coils in a group of PCB coils. The PCB coils need to be sealed, and after sealing, they are arranged in five layers stacked upward in a multi-layer stacking method. This arrangement method can further improve the thrust coefficient of the coil and increase the electromagnetic force between the coil and the magnetic steel after energization.

[0048] Preferably, a material with good thermal conductivity is used for bonding between the PCB coil set 5, the water-cooling pipe 5-2 and the coil backplane 5-1.

[0049] Specific embodiment five: Combine Figures 15 to 16 In this embodiment, there are four groups of stator arrays 4, which are respectively located inside the middle parts of the four straight edges on the upper surface of the micro-stage base 1. The stator array 4 and the stator housing are in interference fit and are connected to the micro-stage base 1 through the stator housing.

[0050] The stator array adopts an improved Halbach array. Compared with the traditional Halbach array, the magnetization directions of the two middle magnets along the x-axis become along the directions at 45° to the x-axis and z-axis. The advantage of this magnetization method is that it can better improve the distortion of the magnetic field, improve the non-linearity of the magnetic field, and make the magnetic field intensity curve present a sine shape. This arrangement can concentrate the magnetic induction intensity above the magnets, place the coil in a stronger magnetic field, increase the thrust coefficient of the motor. Secondly, the magnetic induction intensity below the magnets decreases, making it less susceptible to the influence of the magnetic field of the macro stage. To enhance the magnetic field and increase the thrust coefficient of a single maglev planar motor, the magnet array has a total of four cycles along the x-axis in the above arrangement.

[0051] Specific Embodiment 6: As Figure 3 , Figure 17 described in this embodiment, an X-axis eddy current sensor 7, a Z-axis eddy current sensor 8, and a Y-axis eddy current sensor 9 are provided on the upper surface of the micro stage base 1, and an eddy current sensor reflector 10 is provided on the lower surface of the carrier stage 2.

[0052] The X-axis eddy current sensor 7 is used to measure the x-axis displacement of the micro stage, the Y-axis eddy current sensor 9 is used to measure the y-axis displacement of the micro stage, the difference between the eddy currents y and y1 is used to measure the yaw angle of the micro stage, and the three sensors z1, z2, z3 of the Z-axis eddy current sensor 8 are used to measure and calculate the z-axis displacement, roll angle, and pitch angle of the micro stage. The output forces of the PCB coils 1, 2, 3, and 4 achieve the z-axis displacement of the micro stage. The output forces of the PCB coils 1 and 3 drive the micro stage to move in the x-axis direction, the output forces of the PCB coils 2 and 4 drive the micro stage to move in the y-axis direction. The output force directions of the PCB coils 1, 2, 3, and 4 are in a clockwise or counterclockwise closed loop, which can achieve the adjustment of the yaw angle. Adjusting the output force magnitudes of 1 and 3 can adjust the roll angle of the micro stage, and adjusting the magnitudes of 2 and 4 can adjust the pitch angle of the micro stage.

[0053] The above is only a preferred embodiment of the present invention, and it does not impose any form of limitation on the present invention. Although the present invention has been disclosed above with a preferred embodiment, it is not intended to limit the present invention. Any person skilled in the art, without departing from the technical solution scope of the present invention, can make some changes or modifications to the above-disclosed technical content to obtain equivalent embodiments with equivalent changes. However, as long as it does not depart from the technical solution content of the present invention and is based on the technical essence of the present invention, any simple modification, equivalent replacement, and improvement of the above embodiments still fall within the protection scope of the technical solution of the present invention.

Claims

1. A fast-response magnetic levitation micro-stage driven by a PCB coil, characterized in that: The described fast-response magnetic levitation micro-stage driven by a PCB coil includes a micro-stage base (1), a stage (2), a gravity compensator assembly (3), a stator array (4), a PCB coil group (5), and a limit assembly (6). The stage (2) and the micro-stage base (1) are arranged from top to bottom. The stage (2) and the micro-stage base (1) are connected by the limit assembly (6). The gravity compensator assembly (3) is installed between the micro-stage base (1) and the stage (2). The stator array (4) is connected to the upper surface of the micro-stage base (1). The PCB coil group (5) is installed on the lower surface of the stage (2).

2. The fast-response magnetic levitation micro-stage driven by a PCB coil according to claim 1, characterized in that: The described gravity compensator assembly (3) includes a gravity compensator and a gravity compensator tray (3-2). The gravity compensator is installed in the middle of the upper surface of the micro-stage base (1). The gravity compensator tray (3-2) is installed in the middle of the lower surface of the stage (2). The gravity compensator and the gravity compensator tray (3-2) are connected by screws.

3. The fast-response magnetic levitation micro-stage driven by a PCB coil according to claim 2, wherein: The described gravity compensator includes a housing (3-1), an upper magnet (3-2), an upper magnet back plate (3-3), a middle magnet (3-4), a middle magnet fixing column (3-5), a middle magnet lower plate (3-6), a lower magnet (3-7), and a lower magnet back plate (3-8). The upper magnet (3-2), the middle magnet (3-4), and the lower magnet (3-7) are arranged from top to bottom and are located inside the housing (3-1). The upper magnet (3-2) is installed at the upper end of the housing (3-1) through the upper magnet back plate (3-3). The middle magnet (3-4) is installed in the middle of the housing (3-1) through the middle magnet lower plate (3-6). The lower magnet (3-7) is installed at the lower end of the housing (3-1) through the lower magnet back plate (3-8). The lower end of the middle magnet fixing column (3-5) is fixed to the middle magnet lower plate (3-6), and the upper end sequentially passes through the upper magnet (3-2) and the upper magnet back plate (3-3).

4. A fast-response magnetic levitation micro-stage driven by a PCB coil according to claim 1, characterized in that: The number of the described limit assemblies (6) is four. The four limit assemblies (6) are arranged in a rectangle. Each limit assembly includes a lower limit block (6-1), an upper limit block (6-2), and a limit stud (6-3). The upper limit block (6-2) is installed on the lower surface of the stage (2). The lower limit block (6-1) is installed on the upper surface of the micro-stage base (1). The upper limit block (6-2) and the lower limit block (6-1) are connected by the limit stud (6-3).

5. A fast-response magnetic levitation micro-stage driven by a PCB coil according to claim 4, characterized in that: The upper limit block includes a cylinder. A rectangular block is provided on the lower surface of the cylinder. A threaded hole communicating with the cylinder is provided on the rectangular block for cooperation with the limit stud (6-3). The lower limit block is connected by an upper cylinder and a lower cylinder. The diameter of the upper cylinder is smaller than that of the lower cylinder. A clamping groove for cooperation with the rectangular block is provided on the upper surface of the upper cylinder. A threaded hole for cooperation with the limit stud is provided in the middle of the upper surface of the lower cylinder.

6. A fast-response magnetic levitation micro-stage driven by a PCB coil according to claim 1, characterized in that: The described PCB coil group (5) has four groups, which are respectively located inside the middle of the four straight edges on the lower surface of the stage (2). Each PCB coil group is formed by stacking twenty layers of PCB coils together in sequence.

7. A fast-response magnetic levitation micro-stage driven by a PCB coil according to claim 1, characterized in that: The described PCB coil group (5) is installed on a coil back plate (5-1). A water cooling pipe (5-2) is provided between the coil back plate (5-1) and the PCB coil group (5).

8. A fast-response magnetic levitation micro-stage driven by a PCB coil according to claim 1, characterized in that: The stator array (4) is divided into four groups and is respectively located inside the middle parts of the four straight edges on the upper surface of the micro-stage base (1).

9. A fast-response magnetic levitation micro-stage driven by a PCB coil according to claim 1, characterized in that: The upper surface of the micro-stage base (1) is provided with an X-direction eddy current sensor (7), a Z-direction eddy current sensor (8) and a Y-direction eddy current sensor (9), and the lower surface of the stage (2) is provided with an eddy current sensor reflector (10).

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