JPH0917848A - Magnetic levitation type stage - Google Patents

Abstract

PURPOSE: To obtain a magnetic levitation type stage which enables rapid driving and highly accurate positioning of a movable stage and can be used even in vacuum without lowering cleanliness. CONSTITUTION: In a magnetic levitation type stage with a fixed stage 1 and a moving stage 4 which is driven along the fixed stage 1, a current is made to flow in an electric wire 24 provided to one of the moving stage 4 and the fixed stage 1 in magnetic flux produced a magnet group 5 provided to the other thereof and the moving stage 4 is provided with force in Z-direction by using Lorentz's force which is generated in an electric wire.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a positioning stage used in a semiconductor exposure apparatus, a photoelectron spectroscopy apparatus, an X-ray microscope, a sample analysis apparatus typified by an electron microscope, and the like.

[0002]

2. Description of the Related Art When a semiconductor exposure apparatus is used for exposure, it is necessary to precisely position a wafer in six degrees of freedom of X, Y, Z, α (pitching), β (rolling) and θ (yawing). Further, the photoelectron spectroscopic device, the X-ray microscope, and the electron microscope must similarly position the analysis sample with 6 degrees of freedom. Conventionally, in this field, one-axis drive, two-axis drive, or three-axis drive stages are combined and stacked as needed to be used as a six-axis stage. This stage is equipped with link mechanism such as ball screw, planetary screw, linear screw and lever, drive / deceleration mechanism such as gear, friction roller bearing such as cross roller guide and V-flat groove slide guide, and desired positioning accuracy. To achieve.

[0003]

However, in the conventional stage, the volume of the entire stage is large and it is difficult to reduce the weight. Therefore, the inertial force of the moving stage becomes large, which hinders high-speed driving and it is difficult to improve the positioning accuracy. In addition, since the fixed stage and the moving stage have a mechanical contact surface, the cleanliness of the atmosphere in which the stage is placed is reduced by the dust generated by the moving mechanism. Further, since a lubricant is used for the contact surface, there is a problem that the degree of vacuum is lowered when used in a high vacuum.

In order to realize the non-contact drive of the stage, the moving stage can be levitated by the air bearing and driven by the linear motor, but the air of the air bearing causes dust to fly, thus lowering the cleanliness.
For example, the yield in the semiconductor process is deteriorated. Furthermore, since it uses air, it cannot be used in a vacuum in principle.

An object of the present invention is to provide a magnetic levitation type stage which can be used even in a vacuum without reducing the cleanliness while enabling the moving stage to be lightened to drive the moving stage at high speed and to perform highly accurate positioning. Especially.

[0006]

According to a first aspect of the present invention, when the three axes of the Cartesian coordinate system are X, Y and Z and the rotation angles around the respective axes are represented by α, β and θ, a fixed stage is provided. 1 and a movable stage 4 driven along the fixed stage 1 to an arbitrary position in the XY plane. Then, the moving stage 4 and the fixed stage 1
By applying a current in the magnetic flux formed by the magnet group 5 provided on one of the stages to the electric wire provided on the other stage, a force in the Z direction is applied to the moving stage 4 as described above. The purpose is achieved. Claim 2
In the magnetic levitation stage according to the first aspect of the invention, the wire is a part of the coil 24 wound around the axis in the direction orthogonal to the Z direction. In the invention according to claim 3, when the three axes of the Cartesian coordinate system are X, Y, and Z, and the rotation angles around the respective axes are represented by α, β, and θ, the fixed stage 1 and the fixed stage 1 In a magnetic levitation stage having a moving stage 4 driven to an arbitrary position in the XY plane, a magnet group 5 provided on one of the moving stage 4 and the fixed stage 1 and another stage provided on another stage. A first coil 124 wound around an axis in the X direction or the Y direction, and the first coil 12
4 and a second coil 125 that is wound around the same winding core as that of the first coil 124 and is wound around an axis in a direction orthogonal to both the axial direction and the Z direction of the first coil 124. The above-described object is achieved by applying a current to the second coil 125 to apply a force in the Z direction to the moving stage 4. The invention according to claim 4 is the magnetic levitation type stage according to any one of claims 1 to 3, wherein the magnet group 5 is attached to the other stage with the N pole facing the first magnet. 5d and a second magnet 5e attached with the S pole facing the other stage, and a magnetic flux is generated between the first magnet 5d and the second magnet 5e in a direction orthogonal to the Z direction. 8 is formed. According to a fifth aspect of the present invention, in the magnetic levitation stage according to any one of the first to fourth aspects, the movement amount in the Z direction and the α direction of the moving stage 4 attached to one stage or the other stage. Further, it further comprises a measuring unit 6 for outputting a measured value according to the rotation amount in the β direction, and a control unit 30 for receiving the measured value from the measuring unit 6 and controlling the current. A sixth aspect of the present invention is the magnetic levitation type stage according to any one of the first to fifth aspects, wherein one stage is a moving stage 4 and the other stage is a fixed stage 1. Claim 7
In the magnetic levitation stage according to any one of claims 1 to 6, the invention described in (1) is applied to the moving stage 4 by the attraction force or repulsive force between the magnet group 5 and the electromagnet group 2 provided on the other side. The force is applied in the Z direction.

[0007]

According to the first aspect of the present invention, when a current is passed through the electric wire in the magnetic flux created by the magnet group 5, a force in the Z direction is applied to the moving stage 4 by the Lorentz force. According to the second aspect of the invention, when an electric current is passed through the coil 24 wound around the axis of the electric wire which is orthogonal to the Z direction, the Z-direction force is applied to the moving stage 4 by the Lorentz force. In the invention according to claim 3, when a current is passed through the first coil 124 wound around the axis in the X direction or the Y direction, a force in the Z direction is applied to the moving stage 4 by the Lorentz force. In addition, when a current is applied to the second coil 125 that is wound around the same core as the first coil 124 and is wound around the axis in the direction orthogonal to both the axial direction and the Z direction of the first coil 124. , Z-direction force is applied to the moving stage 4 by the Lorentz force. In the invention according to claim 4, Z is provided between the first magnet 5e attached with the N pole facing and the second magnet 5d attached with the S pole facing the other.
A magnetic flux 8 is created in a direction orthogonal to the direction. Claim 5
In the invention described in (1), the measuring means 3, 6, 7 output measured values according to the movement amount of the moving stage 4 in the Z direction and the rotation amounts of the α direction and the β direction, and the measuring means 3, 6, 7 output the measured values. The control means 30 which has received the measured value controls the current I5. Claim 7
In the invention described in the paragraph 1, the magnet group 5 and the electromagnet group 2 provided on the other side
To the moving stage 4 due to the attraction or repulsion between
Directional force is applied.

[0008] In the means and means for solving the above-mentioned problems which explain the constitution of the present invention, the drawings of the embodiments are used to make the present invention easy to understand. It is not limited to.

[0009]

【Example】

-First Embodiment- FIGS. 1 to 7 show a first magnetic levitation stage according to the present embodiment.
The following shows an example. As shown in FIG. 1, in this embodiment, the three axes of the Cartesian coordinate system are represented by X, Y, and Z, and the rotation angles around the axes are represented by α, β, and θ. Further, α is called pitching, β is rolling, and θ is yawing. As shown in FIG. 1, a plurality of electromagnets 2 are arranged on a rectangular fixed stage 1. As shown in FIG. 2, the electromagnet 2 includes a core 21 having a rectangular parallelepiped shape, a high-permeability member 22 stacked on the upper portion of the core 21, and a core 21 centered on an axis in the Z direction.
And a coil 24 wound around the core 21 around an axis orthogonal to the axis of the coil 23. In FIG. 1, the parallel lines drawn in the square region showing each electromagnet 2 schematically represent the orientation of the coil 24 of each electromagnet 2. As described above, the electromagnets 2 are arranged in a matrix in which the axes of the coils 24 are oriented in the X direction and those oriented in the Y direction. FIG.
As shown in FIG.
The Hall element 3 is attached so as to project above the upper surface of the.

As shown in FIG. 1 and FIG. 3, a rectangular moving stage 4 smaller than the fixed stage 1 floats above the fixed stage 1 with a slight gap. FIG.
Further, as shown in FIG. 4, permanent magnets 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5 are provided on the lower surface of the moving stage 4.
h, 5i, 5j, 5k, and 5l are provided. Of these, permanent magnets 5b, 5c, 5e, 5f, 5g, 5i, 5k
Is the permanent magnet 5a, 5d, with the N pole facing downward in FIG.
5h, 5j, and 5l are attached with the S poles facing downward. Further, three gap sensors 6 for measuring the gap between the moving stage 4 and the fixed stage 1 are attached to the lower surface of the moving stage 4. The three gap sensors measure the amount of movement of the moving stage 4 in the Z direction, the pitching α direction, and the rolling β direction.

As shown in FIG. 1, three laser interferometers 7 are provided around the fixed stage 1. The laser light 7 a emitted from the laser interferometer 7 is reflected by the reflection mirrors on the side surfaces 4 A and 4 B of the moving stage 4 and returns to the laser interferometer 7 again. The three laser interferometers 7 measure the movement amount of the moving stage 4 in the X and Y directions and the rotation amount of the θ direction.

Next, the driving principle of the magnetic levitation type stage of the first embodiment constructed as described above will be explained with reference to FIG. 3 and FIG. 3 is a view taken along the line III-III of FIG. 4, and FIG. 5 is a view taken along the line VV of FIG. In FIG. 3, the electromagnet 2j includes a core 21j and a member 2
2j, coil 23j, and coil 24j, electromagnet 2k
Is the core 21k, the member 22k, the coil 23k, and the coil 24.
k and k respectively. Also, the permanent magnet 5
j is opposed to the electromagnet 2j, and the permanent magnet 5k is opposed to the electromagnet 2k.

In FIG. 3, the coil 23j of the electromagnet 2j is shown.
A current I1 flowing in a clockwise direction when viewed from below. Therefore, the upper side of the electromagnet 2j (core 21j) is N
Since it is a pole, an attractive force is generated between the permanent magnets 5j (the lower side is the S pole) facing each other. A current I2 in the counterclockwise direction when viewed from below flows in the coil 23k of the electromagnet 2k, and an attractive force is similarly generated between the electromagnet 2k and the permanent magnet 5k (N pole on the lower side) facing the electromagnet 2k. .

In FIG. 5, the permanent magnet 5d is an electromagnet 2d.
, And the permanent magnet 5e faces the electromagnet 2e. Further, the electromagnet 2 is placed between the electromagnets 2d and 2e.
de is sandwiched and provided. The electromagnet 2d is the core 21
From d, the member 22d, the coil 23d, and the coil 24d,
The electromagnet 2de includes a core 21de, a member 22de, and a coil 2
3 de and coil 24 de, electromagnet 2e is core 21
From e, the member 22e, the coil 23e, and the coil 24e,
Each is configured.

A current I3 in the counterclockwise direction when viewed from below flows in the coil 23d of the electromagnet 2d.
Since the d (core 21d) has the S pole on the upper side, a repulsive force is generated between the permanent magnet 5d (the S pole on the lower side) facing the d. A current I4 in the clockwise direction when viewed from below flows in the coil 23e of the electromagnet 2e, and a repulsive force similarly occurs between the electromagnet 2e and the permanent magnet 5e (lower side is the N pole) facing the electromagnet 2e.

In FIG. 5, reference numeral 8 indicates the magnetic flux generated by the permanent magnets 5d and 5e. 9 is the current I as described above.
3 and the electromagnet 2d and the electromagnet 2e that have passed the current I4
Shows the magnetic flux generated by. The coil 24de is shown in FIG.
Current I5 is flowing clockwise from the right side of
The Lorentz force acts on the upper part of the coil 24de in a direction (upward direction) in which it approaches the moving stage 4. Since the coil 24de is fixed to the fixed stage 1, a downward force (suction force) Fde having the same magnitude as the Lorentz force is applied to the moving stage 4. Fde by reversing the current of coil 24de
It is also possible to reverse the direction of and generate repulsive force.

As described above, the repulsive force is generated between the electromagnets 2d and 2e and the permanent magnets 5d and 5e which face each other.
An attractive force is generated between the electromagnets 2j and 2k and the permanent magnets 5j and 5k. Further, a current I5 flowing through the coil 24de of the electromagnet 2de causes an attractive force or Lorentz force between the movable stage 4 and the fixed stage 1. Therefore,
If the attraction force and the repulsive force are controlled by the applied electric current, the position of the moving stage 4 in the Z direction, the inclination in the α direction, and the inclination in the β direction can be controlled.

Next, the control of the amount of movement in the X and Y directions and the amount of rotation in the θ direction will be described. As described above, the current I1 flows through the coil 23j of the electromagnet 2j, and the electromagnet 2j
An attractive force is generated between the magnet and the permanent magnet 5j (FIG. 3). In this state, a current I6 in the clockwise direction when viewed from the right further flows through the coil 24j. Therefore, in the portion of the coil 24j above the member 22j, the current I6 flows from the front side to the back side of the paper surface, and in this portion, the force (Lorentz force) in the right direction is received from the permanent magnet 5j. That is, the moving stage 4 (permanent magnet 5j) receives a force Fj1 in the opposite direction (to the left) and the same magnitude as this force from the fixed stage 1 (electromagnet 2j). The direction and magnitude of the force Fj1 received by the moving stage 4 can be controlled by the direction and magnitude of the current I6 flowing through the coil 24j. Further, by increasing / decreasing the current I1 flowing through the coil 23j, the attractive force between the electromagnet 2j and the permanent magnet 5j can be changed (the magnetic flux density can be changed) to control Fj1.

On the other hand, as described above, the coil 2 of the electromagnet 2k
A current I2 flows through 3k, and an attractive force is generated between the electromagnet 2k and the permanent magnet 5k. In this state, when a counterclockwise current I7 is further applied to the coil 24k, a force Fk1 in the direction toward the back of the paper is applied to the moving stage 4 by the same principle as described above. Force Fk received by the moving stage 4
1 can be similarly controlled by the current I7 flowing through the coil 24k and the current I2 flowing through the coil 23k. Since it occurs as described above, Fj1 and Fk1 cause the X direction,
The amount of movement in the Y direction and the amount of rotation in the θ direction are controlled.

In FIG. 4, the permanent magnet 5a is an electromagnet 2a.
(Not shown), the permanent magnet 5b is an electromagnet 2b (not shown), the permanent magnet 5c is an electromagnet 2c (not shown), the permanent magnet 5d is an electromagnet 2d, and the permanent magnet 5e is an electromagnet 2e.
, Permanent magnet 5f is electromagnet 2f (not shown), permanent magnet 5g is electromagnet 2g (not shown), permanent magnet 5h is electromagnet 2h (not shown), and permanent magnet 5i is electromagnet 2i.
(Not shown), the permanent magnet 5j is an electromagnet 2j, the permanent magnet 5k is an electromagnet 2k, and the permanent magnet 5l is an electromagnet 2l.
They are facing each other. Also, the electromagnet 2a and the electromagnet 2b
Between the electromagnet 2ab (not shown), the electromagnet 2ac (not shown) between the electromagnets 2a and 2c, and the electromagnet 2df (not shown) between the electromagnets 2d and 2f. However, the electromagnet 2d is placed between the electromagnets 2d and 2e.
e is an electromagnet 2gh between the electromagnets 2g and 2h.
(Not shown), electromagnets 2hi (not shown) are respectively provided between the electromagnets 2h and 2i.

FIG. 6 shows the force applied to the moving stage 4. Permanent magnets 5a, 5b, 5c, 5d, 5e, 5
f, 5g, 5h, and 5i are forces in the Z direction (repulsive force), respectively.
Fa, Fb, Fc, Fd, Fe, Ff, Fg, Fh, F
receive i. These repulsive forces are generated by the electromagnets 2a, 2b, 2c, 2d, 2e, 2f, 2 facing the respective permanent magnets.
g, 2h, 2i coils 23a, 23b, 23c, 23
It is controlled by the currents passed through d, 23e, 23f, 23g, 23h and 23i. Also, permanent magnets 5j, 5k, 5l
Receives a force (suction force) Fj2, Fk2, Fl2 in the Z direction. These attractive forces are controlled by the currents flowing through the coils 23j, 23k, 23l of the electromagnets 2j, 2k, 2l.
Further, as described in FIG. 4, the coil 2 of the electromagnet 2de is
The stage 4 receives a force Fde (attracting force or repulsive force) in the Z direction via the permanent magnets 5d and 5e by the current of 4 de. The permanent magnet 5 is located above the coil 24ac of the electromagnet 2ac.
Since it is orthogonal to the magnetic flux generated by a and the permanent magnet 5c, the current in the coil 24ac causes the stage 4 to receive the force Fac in the Z direction (attracting force or repulsive force). Similarly, the stage 4 is driven by the current of the coil 24hi of the electromagnet 2hi.
Receives a force Fhi (suction force or repulsion force) in the Z direction.
In this way, the moving stage 4 moves in the Z-direction forces Fa, Fb,
Fc, Fd, Fe, Ff, Fg, Fh, Fi, Fde,
In response to Fac and Fhi, the movement amount in the Z direction and the α direction,
The amount of rotation in the β direction is controlled. In FIG. 6, the force Fd
The case where e, Fac, and Fhi are attraction forces is shown, but if the directions of the currents are reversed, they also act as repulsive forces.

In the state shown in FIG. 6, the coil 24ab of the electromagnet 2ab, the coil 24df of the electromagnet 2df and the coil 24gh of the electromagnet 2gh have windings wound in a direction parallel to the magnetic flux created by the permanent magnets sandwiching the respective electromagnets from both sides. Since it is attached, it does not generate Lorentz force. However, when the moving stage 4 moves in the X direction or the Y direction by the distance of one electromagnet of the fixed stage 1, the windings of these coils 24ab, 24df, and 24gh become orthogonal to the magnetic flux generated by the permanent magnets sandwiching them. Become. Therefore, a force in the Z direction (adsorption force) can be applied to the moving stage 4 by the currents of these coils. In this case, in FIG. 6, the coils 24ac of the electromagnets 2ac, 2de, 2hi that contribute to the attraction force,
Since 24de and 24hi are parallel to the magnetic flux, it is not possible to generate an attractive force.

As shown in FIG. 6, the permanent magnet 5j receives a force Fj1 in the Y direction, the permanent magnet 5k receives a force Fk1 in the X direction, and the permanent magnet 5l receives a force Fl1 in the X direction. These forces are controlled by the currents flowing through the coils 23j and 24j of the electromagnet 2j, the coils 23k and 24k of the electromagnet 2k, and the coils 23l and 24l of the electromagnet 2l. The moving stage 4 moves in the X direction or the Y direction to move the permanent magnets 5.
When the electromagnets facing j, 5k, and 51 change, the direction of the coil 24 changes, so that the directions of the forces Fj2, Fk2, and Fl2 also change.

As shown in FIG. 7, the control device 30 receives information from the hall element 3, the gap sensor 6, and the laser interferometer 7 and controls the current supply device 40 which supplies a current to each coil of the electromagnet 2. . Here, the Hall element 3 detects the magnetic field of the permanent magnet 5 of the moving stage 4 to measure the position and magnetic pole of the permanent magnet 5, and the controller 30 receiving this information determines the coil through which the current flows and the direction of the current. decide. Even when the moving stage 4 moves beyond the pitch of the electromagnet 2, an appropriate current is always supplied to the electromagnets facing the permanent magnets, and the moving stage 4 is appropriately controlled. Also,
The gap sensor 6 measures the gap between the movable stage 4 and the fixed stage 1, and the controller C which receives this information controls the intensity of the current. As a result, Z of the moving stage 4
The amount of movement in the direction and the amount of rotation in the α and β directions are controlled. Further, the laser interferometer 7 measures the amount of movement of the moving stage 4 in the X and Y directions and the amount of rotation in the θ direction, and the controller 30 receiving this information determines the direction and strength of the current flowing through the coil of the electromagnet. Control. As a result, the amount of movement of the moving stage 4 in the X and Y directions and the amount of rotation of the θ direction are controlled. As a control method performed by the controller 30, PD control (proportional differential control), PI control (proportional integral control), PID control (proportional integral differential control), fuzzy control, robust control, or the like can be applied.

Although the amount of movement in the Z direction and the amount of rotation in the α direction and β direction are measured by using three gap sensors 6 in the above, four or more gap sensors are used to improve accuracy. Good. As the types of the gap sensor 6, there are a capacitance sensor, an eddy current sensor, a laser interferometer, and the like, and these may be used alone or in combination of two or more kinds. Although the gap sensor 6 is attached to the movable stage 4 in the first embodiment, it may be attached to the fixed stage 1. In order to measure the gap between the fixed stage 1 and the moving stage 4 more precisely, a plate having good flatness and high magnetic permeability is provided on the upper surface of the fixed stage 1 or the lower surface of the moving stage 4 (the surface facing the gap sensor). May be.

In the first embodiment, the laser interferometer 7 is used to measure the amount of movement of the moving stage 4 in the X and Y directions and the amount of rotation in the θ direction. It is also possible to use a capacitance sensor, an eddy current sensor, or the like. In addition, although three laser interferometers are used in the first embodiment, four or more sensors may be used to improve calculation accuracy.

In the first embodiment, the fixed stage 1
Although the magnetic field of the permanent magnet 5 is detected by the Hall element 3 attached to, the selection of the electromagnet that supplies the current and the direction of the current are determined. However, instead of using the Hall element 3, a laser interferometer 7 may be used. Good. Since the amount of movement of the moving stage 4 in the X and Y directions and the amount of rotation in the θ direction can be calculated from the information from the laser interferometer 7, the selection of the electromagnet and the direction of the current are determined from these amounts of movement and rotation. be able to.

The arrangement of the permanent magnets 5 on the moving stage 4 is the first.
The present invention is not limited to the example. Further, in the first embodiment, the coils 22 of the electromagnets 2 adjacent to each other are arranged so that the directions thereof are orthogonal to each other, but the present invention is not limited to such an arrangement, and a moving stage is arranged according to the arrangement of the electromagnets 2. The arrangement of the permanent magnets 4 of 4 may be appropriately selected. Also,
The number of turns of the coils 22 and 23, the winding density, and the like can be arbitrarily selected. Further, an electromagnet for capturing and shielding the leakage magnetic flux generated from the permanent magnet 5 or the electromagnet 2 may be separately provided. Alternatively, a permanent magnet may be provided on the fixed stage, an electromagnet may be provided on the moving stage, or an electromagnet may be provided on both stages. However, if the permanent magnet is provided on the moving stage as in the present embodiment, wiring to the moving stage becomes unnecessary. In addition, there is an advantage that the moving stage is lightened.

In the first embodiment, the permanent magnets 5j, 5j
Although k and 5 are used, a magnetic material may be used instead of these. In this case, the magnetic material is magnetized by the currents of the coils 23j, 23k, 23l (attracting force is generated), and the current is passed through the coils 22j, 22k, 22l, so that the coils move like the first embodiment. Stage X direction, Y
The amount of movement in the direction and the amount of rotation in the θ direction can be controlled.

In the above description, only the case where the permanent magnets and the electromagnets face each other has been described. However, in the state where the permanent magnets and the electromagnets do not face each other, a current may be supplied to one or a plurality of electromagnets close to the respective permanent magnets. Good. Further, a force may be applied to the moving stage by using another electromagnet provided within a range where the magnetic flux of the permanent magnet reaches.

In the first embodiment, the case where the movable stage that floats on the fixed stage is driven has been described. However, the movable stage floats below the fixed stage by the suction force between the fixed stage and the movable stage. You may do it.

-Second Embodiment- Hereinafter, a second embodiment of the magnetic levitation type stage according to the present invention will be described focusing on the difference from the first embodiment. The same parts as those in the first embodiment are designated by the same reference numerals and the description thereof will be omitted. As shown in FIG. 8, a plurality of electromagnets 102 are arranged in a rectangular fixed stage 101 in the X direction and the Y direction.
Are arranged in the direction. As shown in FIG. 9, the electromagnet 102 includes a rectangular parallelepiped core 121, a high-permeability member 122 stacked on the core 121, and a Z-shaped core 121.
The coil 123 wound around the axis of the direction and the core 1
21 is a coil 124 wound around the Y-direction axis
And a coil 125 wound around the core 121 around the axis in the X direction. As shown in FIG. 11, the Hall element 3 is attached between the adjacent electromagnets 102.

As shown in FIGS. 8 and 10, permanent magnets 105a, 105b, 1 are provided on the lower surface of the moving stage 104.
05c, 105d, 105e, 105f, 105g, 1
05h and 105i are provided. Of these, the permanent magnets 105a, 105d, 105e, 105g, and 105i face the N pole downward, and the permanent magnets 105b, 105c, and 105
f and 105h are attached with the south pole facing down.

Next, the driving principle of the magnetic levitation type stage of the second embodiment having the above-mentioned structure will be described with reference to FIGS.
2 will be described. In FIG. 11, the electromagnet 102h
A current I1 in a clockwise direction when viewed from below flows in the coil 123h. Therefore, since the upper side of the electromagnet 102h (core 121h) has the N pole, an attractive force is generated between the opposing permanent magnet 105h (the lower side has the S pole). A current I2 in the counterclockwise direction when viewed from below flows through the coil 123g of the electromagnet 102g, and an attractive force is similarly generated between the electromagnet 102g and the permanent magnet 105g (the lower side is the N pole) facing the electromagnet 102g. .

In FIG. 12, the permanent magnet 105f faces the electromagnet 102f, and the permanent magnet 105e faces the electromagnet 102e. Also, the electromagnet 102f and the electromagnet 1
An electromagnet 102ef is sandwiched between 02e. A current I3 in the counterclockwise direction when viewed from below flows in the coil 123f of the electromagnet 102f. Therefore, since the upper side of the electromagnet 102f (core 121f) is the S pole,
A repulsive force is generated between the opposing permanent magnets 105f (the lower side is the S pole). A current I4 in the clockwise direction when viewed from below flows in the coil 123e of the electromagnet 102e, and a repulsive force is similarly generated between the electromagnet 102e and the permanent magnet 105e (N pole on the lower side) facing the electromagnet 102e. Reference numeral 108 denotes a magnetic flux generated by the permanent magnets 105f and 105e. Reference numeral 109 denotes a magnetic flux generated by the electromagnets 102f and 102e in which the current I3 and the current I4 have flown as described above. A current I5 is flowing in the coil 125ef in a clockwise direction when viewed from the right side of FIG.
The Lorentz force acts on the upper portion of 5ef in the direction (upward direction) toward the moving stage 104. Since the coil 125ef is fixed to the fixed stage 1, a downward force (suction force) Fef having the same magnitude as the Lorentz force is applied to the moving stage 104. By reversing the current of the coil 125ef, the direction of the force Fef can be reversed to generate a repulsive force.

As described above, between the electromagnet 102f and the permanent magnet 105f facing each other and the electromagnet 102.
e and the permanent magnet 105e, a repulsive force is generated between the electromagnet 10 and
2h and permanent magnet 105h, electromagnet 102g and permanent magnet 1
A suction force is generated between 05g. Also, the electromagnet 102
An attractive force is generated between the moving stage 104 and the fixed stage 101 by the current I5 flowing through the ef coil 125ef. Therefore, if the attraction force and the repulsive force are controlled by the current to be passed, the position of the moving stage 104 in the Z direction and the inclinations in the α direction and the β direction can be controlled.

Next, the control of the movement amount in the X and Y directions and the rotation amount in the θ direction will be described. A current I1 flows through the coil 123h of the electromagnet 102h, and an attractive force is generated between the electromagnet 102h and the permanent magnet 105h (FIG. 1).
1). In this state, the current I6 in the clockwise direction when viewed from the right further flows through the coil 125h. Therefore, as described in the first embodiment, the moving stage 104 receives the leftward force Fh1.

On the other hand, as described above, the current I2 flows through the coil 123g of the electromagnet 102g, and an attractive force is generated between the electromagnet 102g and the permanent magnet 105g. In this state, the current I7 in the counterclockwise direction is further applied to the coil 124g.
Then, the moving stage 4 receives a force Fg1 in the direction toward the back of the paper surface according to the same principle as described above. The forces Fh1 and Fg1 as described above control the amount of movement in the X and Y directions and the amount of rotation in the θ direction.

FIG. 13 shows the force applied to the moving stage 104. The permanent magnet 105a is the electromagnet 102a.
, The permanent magnet 105b is the electromagnet 102b, and the permanent magnet 1 is
05c is an electromagnet 102c, permanent magnet 105d is an electromagnet 102d, permanent magnet 105e is an electromagnet 102e, permanent magnet 105f is an electromagnet 102f, and permanent magnet 105g.
Is the electromagnet 102g and the permanent magnet 105h is the electromagnet 102.
The h and the permanent magnet 105i face the electromagnet 102i, respectively. Also, the electromagnet 102a and the electromagnet 102b
Between the electromagnet 102ab, the electromagnet 2cd between the electromagnets 102c and 102d, and the electromagnet 102e.
Electromagnets 102ef are respectively provided between and the electromagnets 102f.

The permanent magnets 105a, 105b, 105c,
105d, 105e, and 105f receive Z-direction forces (repulsive forces) Fa, Fb, Fc, Fd, Fe, and Ff, respectively. In addition, the permanent magnets 105g, 105h, and 105i respectively exert forces (attraction forces) in the Z direction Fg2, Fh2, and Fi2.
Respectively. Further, the force Fab (attracting force or repulsive force) in the Z direction is generated by the current of the coil 125ab of the electromagnet 102ab, and the coil 124cd of the electromagnet 102cd.
Force Fcd in the Z direction (suction force or repulsive force)
Are respectively subjected to a force Fef (attracting force or repulsive force) in the Z direction by the current of the coil 125ef of the electromagnet 102ef.

As shown in FIG. 13, the permanent magnet 105g exerts a force Fg1 in the Y direction, and the permanent magnet 105h exerts a force Fg in the X direction.
The permanent magnet 105i receives the force Fi1 in the Y direction.

In the second embodiment, the electromagnet 2 has three coils wound around respective axes in the X, Y and Z directions. Therefore, the attraction force, repulsion force, and Lorentz force between the magnets can be effectively used regardless of the position of the moving stage, and the number of permanent magnets on the moving stage can be reduced. Therefore,
The moving stage becomes light in weight and the driving speed can be increased.

In the claims of the present specification, the "magnet" is a concept including a magnetic material that can be magnetized when the moving stage is driven, and is not limited to a permanent magnet.

[0044]

According to the invention described in claim 1, a magnet group is provided on one of the moving stage and the fixed stage, and a current is caused to flow through an electric wire provided on the other stage in the magnetic flux generated by the magnet group. The Lorentz force at that time is used to apply a force in the Z direction to the moving stage. Therefore, since it is possible to avoid mechanical contact between the moving stage and the fixed stage, it is possible to accurately position the moving stage without generating dust. Also,
Since the moving stage can be driven without using air, it can be used even in vacuum. In the invention according to claim 5, since the measuring means for measuring the posture of the moving stage and the controlling means for controlling the current supplied to the wire by receiving the measured value of the measuring means are provided, the moving stage is smoothly controlled. It In the invention according to claim 6, since the movable stage is provided with the magnet group and the fixed stage is provided with the electromagnet, it is not necessary to route the wiring to the movable stage. Further, the electromagnet can be easily cooled.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a first embodiment of a magnetic levitation stage according to the present invention.

FIG. 2 is a perspective view showing an electromagnet of the first embodiment.

FIG. 3 is a diagram showing the operating principle of the first embodiment.

FIG. 4 is a bottom view of the moving stage according to the first embodiment.

FIG. 5 is a diagram showing the operating principle of the first embodiment.

FIG. 6 is a bottom view of the moving stage showing a force received by the moving stage of FIG.

FIG. 7 is a control block diagram of the moving stage according to the first embodiment.

FIG. 8 is a perspective view showing a second embodiment of the magnetic levitation stage according to the present invention.

FIG. 9 is a perspective view showing an electromagnet of a second embodiment.

FIG. 10 is a bottom view of the moving stage according to the first embodiment.

FIG. 11 is a diagram showing the operating principle of the first embodiment.

FIG. 12 is a diagram showing the operating principle of the first embodiment.

13 is a bottom view of the moving stage showing a force received by the moving stage of FIG. 4. FIG.

[Explanation of symbols]

 1 Fixed Stage 3 Hall Element 4 Moving Stage 5 Magnet Group 5e First Magnet 5d Second Magnet 6 Gap Sensor 7 Laser Interferometer 8 Magnetic Flux 24 Coil 30 Controller 124 First Coil 125 Second Coil I5 Current

Claims (7)

[Claims] 1. When the three axes of the Cartesian coordinate system are X, Y, and Z, and the rotation angles around the respective axes are represented by α, β, and θ, a fixed stage and an arbitrary XY plane along the fixed stage. In a magnetic levitation stage having a moving stage driven to the position of, a wire provided on the other stage in a magnetic flux formed by a magnet group provided on any one of the moving stage and the fixed stage. A magnetic levitation stage characterized in that a force in the Z direction is applied to the moving stage by passing an electric current. 2. The magnetic levitation stage according to claim 1, wherein the electric wire is a part of a coil wound around an axis in a direction orthogonal to the Z direction. 3. When the three axes of the Cartesian coordinate system are X, Y, and Z and the rotation angles around the axes are represented by α, β, and θ, a fixed stage and an arbitrary point in the XY plane along the fixed stage. In a magnetic levitation type stage having a moving stage driven to the position, a magnet group provided on one of the moving stage and the fixed stage, and an X direction or a Y direction provided on the other stage. A first coil wound around an axis in a direction orthogonal to each other, and a first coil wound around the same winding core as the first coil and an axial direction of the first coil and Z
A second coil wound around an axis in a direction orthogonal to both directions, and applying a current in the first coil and the second coil to apply a force in the Z direction to the moving stage. A magnetically levitated stage characterized in that 4. The magnet group includes a first magnet attached to the other stage with an N pole facing the second magnet and a second magnet attached to the other stage with an S pole oriented. It consists of a combination and the said magnetic flux is formed between the said 1st magnet and the said 2nd magnet in the direction orthogonal to Z direction, The magnetic flux of any one of Claims 1-3 characterized by the above-mentioned. Magnetically levitated stage. 5. A measuring unit which is attached to the one stage or the other stage and outputs a measured value according to a moving amount in the Z direction and a rotating amount in the α direction and β direction of the moving stage, and the measuring unit. 5. The magnetic levitation type stage according to claim 1, further comprising a control unit that receives the measured value from the control unit and controls the current. 6. The magnetic levitation type stage according to claim 1, wherein the one stage is the movable stage and the other stage is the fixed stage. 7. The Z-direction force is applied to the moving stage by an attractive force or a repulsive force between the magnet group and an electromagnet group provided on the other side. The magnetically levitated stage according to item 1.