KR100917499B1 - Non-contact planar stage and method of controlling the same - Google Patents

Abstract

A non-contact planar stage and a control method thereof are provided to extend a driving area by enlarging a conductive plate. A first directional linear induction motor unit includes a plurality of linear induction motors arranged in parallel. A second directional linear induction motor unit includes a plurality of linear induction motors arranged in an orthogonal direction to the first directional linear induction motor unit. At least one of the linear induction motors is arranged to generate the thrust of the opposite direction of the other linear induction motors inside the same linear induction motor unit. Each linear induction motor includes a plurality of ferromagnetic cores and a coil wound around the ferromagnetic cores. A non-contact planar stage(100) is moved on the conductive plate with a ferromagnetic uneven part(300) by the magnetic force generated between the first directional linear induction motor unit, the second directional linear induction motor unit, and a conductive plate(310).

Description

Non-contact planar stage and method of controlling the same

The present invention relates to a planar stage, and more particularly to a planar stage and a control method thereof that floats and moves on a conductive plate.

Planar stages are essential equipment used in the manufacturing process and inspection of wafer steppers for semiconductor exposure processes, flat panel devices (FPDs) including TFT-LCDs. However, in order to reduce the manufacturing cost of flat-panel display discs using 12-inch wafer handling and multi-faceted process, related companies are committed to developing flat stages with a larger working area and more precise resolution. There are limits to addressing this need. The expansion of the work space of the flat stage requires not only the expansion of components but also a high degree of expertise in the field of assembly technology, so that only a few companies around the world manufacture products that meet the design specifications of the current industrial site. There is only.

As a conventional technology related to such a planar stage, a technology such as a positioning device (Korea Patent No. 10-0193153) is disclosed, and FIG. 1 is a schematic view showing a technique of such a conventional planar stage. As shown in FIG. 1, a conventional general planar stage has linear motor blocks 2, 3, 2 ′, 3 ′ on a base 1 that produce y-axis motion and the linear motor blocks 2, 3, 2. Another linear motor 5 orthogonal to ', 3') produces the x-axis motion. The stacked structure of the linear motor blocks 2, 3, 2 ', 3 and the linear motor 5 is a planar stage structure of the most common type which is currently commercially available, and the linear motors are guided by linear guides or along a guide surface. It is driven non-contact by air bearings.

However, due to the laminated structure, there is a great difficulty in the expansion of the planar stage, and as the assembly tolerances between the driving elements overlap and affect the overall precision of the planar stage, a high level of expertise is required when assembling the planar stage. The bigger it gets, the worse it gets.

In addition, the planar stage of such a laminated structure also has a problem that requires a lot of power in driving the planar stage.

Accordingly, a large-area stage device (Korea Republic Patent No. 10-0726711) of a magnetic levitation type is disclosed as a technology related to a flat stage using a magnetic levitation method rather than a stacked structure. Figure 2 is a schematic diagram schematically showing a planar stage of such a magnetic levitation method. As shown in the figure, the magnetic levitation type large area stage apparatus includes a lower plate 50 having a support plate 51, a support plate 52 supporting the same, and an upper surface of the support plate 51. A coil module array 54 installed at the side to generate an electromagnetic field, a stage 55 floating and conveyed from the upper side of the lower transfer table 50, and a permanent magnet array 58 provided at a lower surface of the stage 55. It consists of Herein, the electromagnetic field generated by the coil module array 54 magnetically interacts with the permanent magnet array 58 below the stage 55, whereby the stage 55 is magnetically floated and propagated. In the case of the stage 55 having the lower structure of the coil module array 54, the expansion of the work area is solved by overlapping the lower coil array in the x and y-axis directions. As a result, thrust ripple due to power switching at the boundary of adjacent coils is inevitably present.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and to provide a non-contact planar stage which can simply expand the driving region by only expanding the conductive plate by moving the plane stage on the conductive plate in a non-contact manner.

Another object of the present invention is to generate a magnetic force in the non-contact planar stage by the interaction between the non-contact planar stage and the conductive plate to prevent the thrust ripple due to the phase change of the power supplied to the non-contact plane An object is to provide a non-contact planar stage capable of precisely driving control of the stage.

In order to achieve the above object, the non-contact planar stage according to the present invention is a first direction linear induction motor unit having a plurality of linear induction motors arranged side by side with each other in a direction orthogonal to the first direction linear induction motor unit A non-contact planar stage including a second direction linear induction motor unit having a plurality of linear induction motors arranged side by side, wherein at least one of the linear induction motors arranged in parallel with each other in each linear induction motor unit is the same linear induction motor The linear induction motors are arranged to generate a thrust in the opposite direction to other linear induction motors. Each linear induction motor has a plurality of ferromagnetic cores arranged in a line and a coil wound around the iron core of each ferromagnetic core. The first direction linear induction motor part and the second direction linear induction on a conductive plate having ferromagnetic uneven plate It characterized in that the movement by the magnetic force generated between the taboo and the conductive plate.

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The first directional linear induction motor unit may be spaced apart from the first linear induction motor unit and the first linear induction motor unit in which a plurality of linear induction motors are arranged adjacent to each other in the first direction. A second linear induction motor unit is arranged in a direction parallel to the linear induction motor unit adjacent to each other, the second linear induction motor unit, the second direction linear induction motor unit, the plurality of linear induction motors are arranged adjacent to each other side by side. The third linear induction motor unit is arranged in a direction orthogonal to the first linear induction motor unit and the second linear induction motor unit, and the third linear induction motor unit spaced apart from the third linear induction motor unit And a fourth linear induction motor unit in which a plurality of linear induction motors are arranged adjacent to each other in parallel with each other in a direction parallel to each other.

The first to fourth linear induction motor unit is characterized by forming a rectangular shape.

Each of the first to fourth linear induction motors is configured such that three linear induction motors are arranged in three rows, and the linear induction motor in the middle row among the three linear induction motors has a thrust in a direction opposite to the other two linear induction motors. It is characterized in that it is formed to generate.

The air bearing is further provided between the first and second direction linear induction motors.

The non-contact planar stage includes a magnetic flux sensor, a displacement sensor capable of measuring a change amount of movement of the non-contact planar stage, and a controller capable of controlling the driving of the non-contact planar stage according to data detected by the magnetic flux sensor and the displacement sensor. Characterized in that it comprises a.

According to the present invention, since the non-contact planar stage floats and moves in a non-contact manner on the conductive plate, it is possible to simply expand the driving region by only expanding the conductive plate.

In addition, since the non-contact planar stage has a bias thrust generation structure, the drive control of the non-contact planar stage is precisely controlled by constantly controlling the floating force and the propulsion force generated in the non-contact planar stage without the periodic force ripple of the linear induction motor. can do.

Advantages and features of the present invention and methods for achieving them will be apparent with reference to the preferred embodiments described below in detail in conjunction with the accompanying drawings. However, the present invention is not limited to the preferred embodiments disclosed below, but can be implemented in various forms, and only the present preferred embodiments make the disclosure of the present invention complete, and are common in the art to which the present invention pertains. It is provided to fully inform those skilled in the art of the scope of the invention, which is to be defined only by the scope of the claims. Like reference numerals refer to like elements throughout.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Figure 3 is an attempt to show the overall appearance of a non-contact planar stage according to the present invention, Figure 4 is a reference diagram showing the arrangement of the linear induction motor of the non-contact planar stage according to a preferred embodiment of the present invention, Figure 5 is the present invention FIG. 6 is a perspective view illustrating a configuration of a linear induction motor that is a component of a non-contact planar stage according to FIG. 6, FIG. 6 is a perspective view illustrating various embodiments of a core part of the linear induction motor of FIG. 5, and FIG. 7 is a frequency of the linear induction motor of FIG. 5. Figure 8 is a diagram showing a change in the thrust and the vertical force in accordance with the change, Figure 8 is a reference diagram showing the state in which a plurality of linear induction motors are arranged adjacent to each other and the thrust generated in the plurality of linear induction motors.

9 is a diagram showing the magnetic force and the air pressure generated in the linear induction motor unit of the non-contact planar stage according to a preferred embodiment of the present invention, Figure 10 is a component of the non-contact planar stage according to a preferred embodiment of the present invention FIG. 11 is a control diagram of a non-contact planar stage according to a preferred embodiment of the present invention, and FIG. 12 is a component of a non-contact planar stage according to a preferred embodiment of the present invention. A vector control flow chart for biaxial magnetic force independent control of a linear induction motor.

Hereinafter, the components of the non-contact planar stage 100 according to the preferred embodiment of the present invention will be described, and then the operation and driving control of such a non-contact planar stage 100 will be described.

First, the non-contact planar stage 100 according to the preferred embodiment of the present invention is provided with a main body frame 101 for supporting each component, as shown in Figure 3 and 4, the bottom of the main body frame 101 A plurality of linear induction motor unit 110, 120, 130, 140 to be supplied to the air bearing 200 and the non-contact planar stage (100) provided in the lower edge portion of the main body frame 101 The cable 500 is comprised.

In addition, the linear induction motor unit 110, 120, 130, 140 of the non-contact planar stage 100 may generate a magnetic force to move the non-contact planar stage 100 to form a quadrangular flat plate-like conductive plate 310. A ferromagnetic uneven plate 300 is further provided below the conductive plate 310.

The linear induction motor parts 110, 120, 130, and 140 provided in the non-contact planar stage 100 are provided such that four linear induction motor parts 110, 120, 130, and 140 have a rectangular shape. That is, as shown in FIG. 4, the first linear induction motor unit 110 and the second linear induction motor are provided on the upper side and the lower side (the + Y axis direction of FIG. 4 is upper side) spaced apart by a predetermined interval. The first and second linear inductions on the left and right sides (the + X axis direction in FIG. 4 is right) of the unit 120 and the first linear induction motor unit 110 and the second linear induction motor unit 120. Similar to the motor parts 110 and 120, the third linear induction motor part 130 is spaced apart by a predetermined interval and arranged in parallel with each other, but is provided in a direction orthogonal to the first and second linear induction motor parts 110 and 120. ) And the fourth linear induction motor unit 140.

The first to fourth linear induction motors 110, 120, 130, and 140 are formed in such a manner that the coils 114 are wound around the plurality of ferromagnetic cores 112 arranged in a line and iron cores of the ferromagnetic cores 112. Three linear induction motors 111 are configured to be arranged in three rows adjacent to each other next to each other. Here, the plurality of ferromagnetic cores 112 arranged in a line for generating a moving magnetic flux may be simultaneously formed with a moving magnetic flux and a transverse magnetic flux by an integral core form 116 or a core having an upper end connected thereto, as shown in FIG. 6. It can be carried out in a variety of forms, such as a cross pill core 118.

The air bearings 200 are provided between the first to fourth linear induction motor parts 110, 120, 130, and 140, that is, at four corners. When the vertical force generated in the first to fourth linear induction motor parts 110, 120, 130, and 140 is a high frequency band, the air bearing 200 acts as a repulsive force to float the non-contact planar stage 100. When the low frequency band acts in the form of a suction force to compensate for such a suction force to float the non-contact planar stage 100.

The air bearing 200 may be provided with a fan and a motor to generate compressed air, or may be provided with a compressed air supplied from the outside to eject the compressed air to the outside.

The non-contact planar stage 100 includes a magnetic flux sensor (not shown), a displacement sensor (not shown) capable of measuring a change amount of movement of the non-contact planar stage 100, and data detected by the magnetic flux sensor and the displacement sensor. The control unit (not shown) for controlling the driving of the non-contact planar stage 100 is further provided. The magnetic flux sensor, the displacement sensor, and the control unit for controlling the non-contact planar stage 100 according to the data detected from the sensors will be described later in detail.

Hereinafter, the basic operating principle of the non-contact planar stage 100 configured as described above will be described. First, in the non-contact planar stage 100 according to the preferred embodiment of the present invention, the first to fourth linear induction motor parts 110, 120, 130, and 140 provided in the non-contact planar stage 100 are grouped. The reason that is configured as will be described.

As shown in FIG. 5, when a polyphase power is applied to the linear induction motor placed on the conductive plate 310, that is, the coil 114 having the ferromagnetic core 112 iron core, an eddy current generated from the conductive plate 310 is generated. The magnetic field of the coil 114 generates a thrust 410 in the ± X axis direction and a vertical force 400 in the −Z axis direction.

At this time, in order to change the thrust direction of the linear induction motor 111 generated in the ± X-axis direction, it is necessary to switch the phase of the polyphase power applied to the coil 114. However, when the phase of the multi-phase power source is switched in order to change the moving direction of the non-contact plane stage 100 while the non-contact plane stage 100 is moving at a constant or low speed, the input power applied to the coil 114 is changed. It leads to discontinuities.

This causes a discontinuity in the thrust generated by the linear induction motor 111, this discontinuity of the thrust is a great constraint to secure the uniform dynamic characteristics of the non-contact planar stage (100). The thrust direction change of the phase shift method is an inevitable condition in the induction principle. In the present embodiment, the first to fourth linear induction motors 110 and 110 may have a bias thrust generation structure to eliminate the discontinuity of the thrust. 120, 130, 140) were provided in a group form.

That is, as shown in FIG. 8, three linear induction motors 116, 117, and 118 are provided in three rows, and then these linear induction motors 116, 117, and 118 generate thrust in different directions. The non-contact planar stage 100 is moved, changed direction during movement, or stopped by a combination of these forces.

For example, in the linear induction motors 116 and 118 in the first row and the lower row, thrust is generated in the + X (F1, F3) axis direction, and in the linear induction motor 117 in the middle row, the -X (F2) axis direction. When the thrust in the + X (F1, F3) axis direction and the thrust in the -X (F2) axis direction are equal to each other when the thrust is generated, the forces of each other cancel each other and the thrust does not occur in any direction so that the non-contact Planar stage 100 is in a stationary state.

And if you want to move the non-contact planar stage 100 in the + X-axis direction or -X-axis direction to generate a thrust in the direction to move further to move the non-contact planar stage 100 to change the direction of movement Then, the direction can be changed by generating more thrust in the opposite direction or by lowering the thrust generated in the opposite direction to the change direction.

In addition, the first to fourth linear induction motors arranged in such a three-column form are arranged in the up, down, left, and right directions of the non-contact planar stage 100 so that the non-contact planar stage 100 is up, down, or left. , Move it to the right.

The first to fourth linear induction motors 110, 120, 130, and 140 provided in such a form can prevent discontinuity due to phase change when changing the direction of the non-contact planar stage 100 and increase driving accuracy. Can be. Such a structure is not limited to the illustrated three-column form, and in addition to the most basic structure in which the linear induction motor 111 faces each other, it is possible to implement such a variety of arrangements.

In addition, the first to fourth linear induction motor unit (110, 120, 130, 140) of

The arrangement is not just arranged in a rectangular shape on the top, bottom, left, right of the non-contact planar stage 100 as described above, but can move the magnetically levitated moving object 100 in the up, down, left, and right directions. It can be provided in the form of an arrangement of any form.

Hereinafter, to the air bearing 200 provided in the non-contact planar stage 100

This will be described.

If the polyphase power applied to the coil 114 is a low frequency band, a strong suction force acts between the magnetic field of the coil 114 and the ferromagnetic unevenness 300. FIG. 7 is a diagram illustrating changes in thrust and vertical force of the first to fourth linear induction motor parts 110, 120, 130, and 140 according to the frequency change of the polyphase power applied to the coil 114. Likewise, in the case of thrust, it increases with frequency and starts to decrease, and as the high frequency increases, it decreases with little decrease, but in the case of vertical force, the direction is changed according to the frequency change. In other words, it takes the form of suction force in the low frequency band and repulsive force in the high frequency band.

The reason for having the shape of the suction force in the low frequency band as described above is that the force due to the eddy current induced in the conductive plate 310 is the repulsive force, but in the low frequency band the suction force between the magnetic field of the coil 114 and the ferromagnetic unevenness 300 is very high. Because of the size.

Therefore, when the non-contact planar stage 100 according to the preferred embodiment of the present invention is driven in a low frequency band, a total magnetic force in eight axial directions such as four thrust and four suction forces is generated. Accordingly, in this embodiment, the suction force is compensated to raise the non-contact planar stage 100 in the space above the conductive plate 310 and increase the control bandwidth of the system by the effect of the bias stiffness in the void direction. An air bearing 200 was provided at the lower four corners of the non-contact planar stage 100.

Hereinafter, driving control of the non-contact planar stage 100 according to the preferred embodiment of the present invention will be described.

의 방향이 항상 그림과 같도록 코일(114)에 다상 전원을 인가하면, 최종 힘

은 다음의 식(1)과 같이 얻어진다.Thrust generated in the linear induction motors 116, 117, and 118, which are configured in three rows as shown in FIG. 8.

When the multiphase power is applied to the coil 114 so that the direction of is always as shown in the figure, the final force

Is obtained as in the following equation (1).

(1)

(One)

(2) Here, the thrust on the right is divided into a nominal value and a small change amount based on the nominal value, as shown in Equation (2) below.

(2)

(3)

(3)

Therefore, as shown in Equation (3), the direction of thrust generated in the linear induction motors 116, 117, and 118 is determined by the difference in the amount of small change of the linear induction motors 116, 117, and 118. It can be seen that the thrust direction of the induction motors 116, 117, 118 itself is always intact. Therefore, the motion of the non-contact planar stage 100 can be controlled by controlling the difference of the minute change amount.

In this case, the nominal value is preferably equal to or greater than a predetermined level because the nominal value is so small that the magnetic levitation moving device 100 is greatly influenced by the driving even if the difference in the amount of change is minute. This is because it is impossible to control stable and precise driving.

와 같이 -z축의 방향으로 작용한다. 상기 비접촉 평면 스테이지(100)의 질량을 m, 각 축에 대한 관성 모멘트를 각각

그리고 무게 중심에서 각 힘까지의 모멘트 암을

라 하면 상기 비접촉 평면 스테이지(100)의 무게 중심점에서는 식(4), (5)와 같은, 면내 운동(

)과 면외 운동(

)에 대한 힘 평형 방정식이 성립된다.9 shows a magnetic force and a pneumatic pressure diagram acting on the non-contact planar stage 100 according to the present invention. Acts as a flotation force. In this case, since the magnetic attraction force in FIG. 9 is a force acting on the conductive plate 310, the conductive plate 310 is fixed and the non-contact planar stage 100 is driven.

It acts in the direction of the -z axis. The mass of the non-contact planar stage 100 m, the moment of inertia for each axis

And the moment arm from the center of gravity to each of the forces

In terms of the center of gravity of the non-contact planar stage 100, in-plane motions such as equations (4) and (5)

) And out-of-plane exercise (

The force equilibrium equation for

(4)

(4)

(5)

(5)

      Therefore, as can be seen in the above equation, when the design momentum of the non-contact planar stage 100 is determined, the values for the respective thrust and the vertical force are calculated based on Equations (4) and (5).

10 is a simplified diagram showing the coordinate system and power connection of the linear induction motor 111 in the non-contact planar stage 100 according to the present invention, the input of the linear induction motor 111 is three-phase (u, v, w) Power, but output is the vertical force and thrust acting on the conductive plate 310, so an independent one-to-one relationship is not established between the input and the output. However, if the d-axis is set to coincide with the u-phase axis of u, v, w as shown in the figure, and the q-axis is set to have a phase angle of 90 degrees with the axis, in the general vector control method, d The axial current is used for the pore magnetic field, that is, the vertical force control, and the q-axis current is used for the thrust control. Since the vector sum of the three-phase power source, i.e., the image current is zero, the independent variable of the three-phase power source can be reduced to two. Therefore, if these two variables are replaced with d and q-axis currents, the biaxial force is controlled by the two variables. It is possible. At this time, the instantaneous position value of the magnetic flux of the first to fourth linear induction motor units 110, 120, 130, and 140 of the non-contact planar stage 100 should be continuously monitored, and the d-axis is synchronized to the instantaneous position of the magnetic flux. Let's do it.

11 shows a control flowchart of the non-contact planar stage 100 according to the present invention. The spatial position measurement of the non-contact planar stage 100 is performed by separately measuring in-plane motion and out-of-plane motion, and the measured position value is an analog voltage. The analog-to-digital converter converts the digital value to generate an appropriate control input in comparison with the reference input in the controller, and the analog power is applied to the linear driver through the linear motor driver according to the control amount. The non-contact planar stage 100 is floated and propagated in the space by the magnetic force of the linear induction motor units 110, 120, 130, and 140 generated through the applied power, and the amount of the non-contact planar stage 100 is transferred again. It has a closed loop structure that is measured and fed back to the controller.

 12 shows a vector control flow chart for biaxial magnetic force independent control of the linear induction motor 111 which is a component of the non-contact planar stage 100 according to the present invention. As described above, the linear induction motor 111 is in addition to the thrust. Since the vertical force is generated, the vector controller method is applied mutatis mutandis as a means for controlling the biaxial magnetic force using the three-phase power source of the linear induction motor 111. When the target vertical force and the thrust amount of the linear induction motor 111 are determined, the d-axis current, which is the magnetic field control current, and the q-axis current, which is the thrust control current, are calculated according to the three-phase power supply of u, v, and w as actual power input forms. It is converted and fed to the linear induction motor through the inverter. The position of the magnetic flux of the linear induction motor 111 is measured by the magnetic flux sensor installed at the bottom of the core 114 and the measured position is fed back to synchronize the d-axis to the magnetic flux axis. In addition, the non-contact planar stage 100 is driven by the magnetic force by the linear induction motor 111 and air pressure to compensate the vertical magnetic force, and the position of the non-contact planar stage 100 is measured by a 6-axis displacement sensor. It is fed back to the controller.

   Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art to which the present invention pertains can implement the present invention in other specific forms without changing the technical spirit or essential features, The embodiments are to be understood in all respects as illustrative and not restrictive.

Therefore, the scope of the present invention is defined by the following claims rather than the detailed description, and all changes or modifications derived from the meaning and scope of the claims and equivalent concepts are included in the scope of the present invention. Should be interpreted as

1 and 2 are schematic diagrams schematically showing the configuration of a conventional stage.

Figure 3 is a perspective view showing the overall appearance of a non-contact planar stage according to the present invention.

4 is a reference diagram showing the arrangement of the linear induction motor in a non-contact planar stage according to a preferred embodiment of the present invention.

Figure 5 is a perspective view showing the configuration of a linear induction motor that is a component of a non-contact planar stage according to the present invention.

6 is a perspective view illustrating various embodiments of a core part of the linear induction motor of FIG. 5.

7 is a diagram showing a change in thrust and vertical force in accordance with the change in frequency in the linear induction motor of FIG.

8 is a reference diagram illustrating a state in which a plurality of linear induction motors are arranged next to each other and a force generated in the plurality of linear induction motors.

9 is a diagram showing the magnetic force and air pressure generated in the linear induction motor unit of a non-contact planar stage according to a preferred embodiment of the present invention.

10 is a simplified diagram showing the coordinate system and power connection of the linear induction motor which is a component of the non-contact planar stage according to the preferred embodiment of the present invention.

11 is a control flow diagram of a non-contact planar stage in accordance with a preferred embodiment of the present invention.

12 is a vector control flowchart for biaxial magnetic force independent control of a linear induction motor which is a component of a non-contact planar stage according to a preferred embodiment of the present invention.

<Description of the symbols for the main parts of the drawings>

100: non-contact planar stage 110: first linear induction motor unit

120: second linear induction motor unit 130: third linear induction motor unit

140: fourth linear induction motor unit 200: air bearing

      300: ferromagnetic uneven plate 310: conductive plate

Claims (6)

A first direction linear induction motor unit having a plurality of linear induction motors arranged side by side and a second direction linear having a plurality of linear induction motors arranged side by side in a direction orthogonal to the first direction linear induction motor unit A non-contact planar stage comprising an induction motor unit, At least one of the linear induction motors arranged in parallel with each other in the linear induction motor parts is arranged to generate thrust in a direction opposite to other linear induction motors in the same linear induction motor part, The linear induction motors are configured in a form in which coils are wound around iron cores of a plurality of ferromagnetic cores and each ferromagnetic core arranged in a line, And a non-contact planar stage which is moved by a magnetic force generated between the first direction linear induction motor part and the second direction linear induction motor part and the conductive plate on a conductive plate having a ferromagnetic uneven plate at a lower portion thereof. The method of claim 1, The first direction linear induction motor unit, A first linear induction motor unit in which a plurality of linear induction motors are arranged adjacent to each other in the first direction; Comprising a second linear induction motor unit spaced apart from the first linear induction motor unit, a plurality of linear induction motors are arranged adjacent to each other in parallel with the first linear induction motor unit, The second direction linear induction motor unit, A plurality of linear induction motors arranged side by side adjacent to each other and arranged in a direction orthogonal to the first linear induction motor part and the second linear induction motor part; A non-contact planar stage comprising a fourth linear induction motor part spaced apart from the third linear induction motor part so that a plurality of linear induction motors are arranged adjacent to each other in parallel with the third linear induction motor part . The method of claim 2, And the first to fourth linear induction motor parts have a rectangular shape. The method of claim 2, Each of the first to fourth linear induction motors is configured such that three linear induction motors are arranged in three rows, and the linear induction motor in the middle row among the three linear induction motors has a thrust in a direction opposite to the other two linear induction motors. Non-contact planar stage, characterized in that it is formed to generate. The method of claim 1, Non-contact planar stage, characterized in that the air bearing is further provided between the first and second direction linear induction motor portion. The method according to any one of claims 1 to 5, The non-contact planar stage has a magnetic flux sensor, A displacement sensor capable of measuring a change amount of movement of the non-contact planar stage; And a control unit for controlling driving of the non-contact planar stage according to the data detected by the magnetic flux sensor and the displacement sensor.

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