JPH0917847A - Magnetic levitation type stage - Google Patents

Abstract

PURPOSE: To obtain a magnetic levitation type stage which enables rapid driving of a moving stage and highly accurate positioning and can be used even in vacuum by adopting a method including providing of a moving stage with movement force and rotary force due to repulsion force and attraction force between a magnet group and an electromagnet group. CONSTITUTION: When three axes of an orthogonal coordinates system are X, Y, Z and each axis-wise rotation angle is expressed by α, β, θ, the title device has a fixed stage 1 and a moving stage 4 which is driven to an arbitrary position inside an XY plane along the fixed stage 1. The moving stage 4 is provided with movement force in Z-direction and rotation force in α-direction and β-direction by repulsion force or attraction force between first magnet groups 5a to 5f provided to one of the stages 1, 4 and a first electromagnet group 2 provided to the other thereof. The moving stage 4 is provided with movement force in X-direction and Y-direction and rotation force in θ-direction in magnetic flux generated between the second magnet groups 5b, 5c, 5e provided to one of the stages 1, 4 and a second electromagnet group 2 provided to the other thereof by a transverse current made to flow 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. In addition, since air is used, 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
A first magnet group 5a provided on one of the stages,
5b, 5c, 5d, 5e, 5f and the first electromagnet groups 2a, 2b, 2c, 2d, 2e, 2f provided on the other stage.
The moving force in the Z direction and the rotating force in the α direction and the β direction are applied to the moving stage 4 by the repulsive force or the attractive force between the second magnet group 5b and the second magnet group 5b provided on one stage.
5e and the second electromagnet groups 2b, 2 provided on the other stage
Applying a moving force in the X direction, the Y direction and a rotating force in the θ direction to the moving stage 4 by the transverse currents I5 and I6 flowing in the electric wire provided on the other stage in the magnetic flux created between the c and 2e. The above-mentioned object is achieved by. The invention according to claim 2 is the magnetic levitation type stage according to claim 1, wherein each electromagnet of the second electromagnet groups 2b, 2c, and 2e is a first coil wound around an axis in the Z direction. 23b,
23c and 23e, and second coils 22b, 22c and 22e wound around an axis in the X or Y direction,
A transverse current I is applied to the second coils 22b, 22c and 22e.
5 and I6 are made to flow. According to a third aspect of the present invention, in the magnetic levitation type stage according to the first aspect, each electromagnet of the second electromagnet group 2 has a first coil 123 wound around an axis in the Z direction and an X-axis. Alternatively, a second coil 124 wound around an axis in the Y direction and a third coil 125 wound around an axis orthogonal to both the Z direction and the axial direction of the second coil 124 are provided. The second coil 124 and / or the third coil 125 are provided with cross currents I5, I6, and I7. The invention according to claim 4 is the magnetic levitation type stage according to any one of claims 1 to 3, wherein the movable stage 4 is driven on the fixed stage 1, and the first magnet group has an attractive force. It includes a magnet 5e 'that produces only a magnetic field. The invention according to claim 5 is the magnetic levitation type stage according to any one of claims 1 to 4, wherein the movable stage 4 is attached to the movable stage 4 or the fixed stage 1.
Of the first electromagnet group 2a that receives a measurement value from the first measurement means 6 that outputs a measurement value according to the amount of movement in the Z direction and the amount of rotation in the α direction and the β direction. 2b,
2c, 2d, 2e, 2f is provided with the first control means 30 for controlling the current. The invention according to claim 6 is the magnetic levitation stage according to any one of claims 1 to 5, in which measurement is performed according to the amount of movement of the moving stage 4 in the X and Y directions and the amount of rotation in the θ direction. A second measuring means 7 for outputting a value, and a second measuring means 7 for receiving a measured value from the second measuring means 7 and controlling a crossing current I5, I6 and / or a current of the second electromagnet group 2b, 2c, 2e. Control means 3
0 and. The invention according to claim 7 is the magnetic levitation stage according to any one of claims 1 to 5, in which measurement is performed according to the amount of movement of the moving stage 4 in the X and Y directions and the amount of rotation in the θ direction. Second measuring means 3 and 7 for outputting a value, and a first electromagnet group 2a of the electromagnets attached to the fixed stage 1 or the moving stage 4 upon receiving the measured values from the second measuring means 3 and 7. 2b, 2c, 2
The second control means 30 is provided for selecting the electromagnets to be used as d, 2e, and 2f and setting the direction of the current of each selected electromagnet. According to an eighth aspect of the invention, in the magnetic levitation type stage according to the seventh aspect, the second measuring means 3 and 7 are the hall elements 3 attached to the fixed stage 1 or the moving stage 4. According to a ninth aspect of the present invention, in the magnetic levitation stage according to any one of the first to fifth aspects, measurement is performed according to the movement amount of the moving stage 4 in the X and Y directions and the rotation amount in the θ direction. Second measuring means 3 and 7 for outputting a value, and a second electromagnet group 2b of the electromagnets attached to the fixed stage 1 or the moving stage 4 in response to the measured values from the second measuring means 3 and 7. The second control means 30 is provided for selecting the electromagnets used as 2c and 2e and for setting the direction of the current of each electromagnet. According to a tenth aspect of the present invention, in the magnetic levitation stage according to the ninth aspect, the second measuring means 3 and 7 are the hall elements 3 attached to the fixed stage 1 or the moving stage 4. The invention described in claim 11 is any one of claims 1 to 10.
In the magnetic levitation stage described in the item 1, the first magnet group 5a, 5b, 5c, 5d, 5e, 5f and the second magnet group 5 are included.
b, 5c, 5e, the first electromagnet groups 2a, 2b, 2c, 2
d, 2e, 2f or the second electromagnet group 2b, 2c, 2
e is made of a superconducting material. According to a twelfth aspect of the present invention, in the magnetic levitation type stage according to any one of the first to eleventh aspects, one stage is a moving stage 4 and the other stage is a fixed stage 1.
It is what it was.

[0007]

According to the first aspect of the invention, the first magnet groups 5a, 5b, 5c, 5d, 5e, 5f provided on one of the moving stage 4 and the fixed stage 1 and the other stages are provided on the other stage. The first electromagnet group 2a, 2b, 2c,
A repulsive force or a suction force between 2d, 2e, and 2f applies a moving force in the Z direction and a rotating force in the α direction and the β direction to the moving stage 4. In addition, in the magnetic flux created between the second magnet group 5b, 5c, 5e provided on one stage and the second electromagnet group 2b, 2c, 2e provided on the other stage, the magnetic field is provided on the other stage. Wires 22b, 22c, 2
When the transverse currents I5 and I6 are applied to 2e, X is applied to the moving stage 4.
Direction, a moving force in the Y direction and a rotating force in the θ direction are given. In the invention described in claim 2, the first coils 23b, 23c, 23e wound around the Z-direction axis and the axes orthogonal to the first coils 23b, 23c, 23e are wound around the first coils 23b, 23c, 23e. When the transverse currents I5 and I6 are passed through the second coils 22b, 22c, and 22e, the moving force in the X and Y directions and the turning force in the θ direction are applied to the moving stage 4. In the invention according to claim 3, the second coil 124c
And the transverse current I in the third coils 125b and 125c.
When 5, I6 and I7 are passed, the moving force in the X and Y directions and the turning force in the θ direction are applied to the moving stage 4. In the invention according to claim 4, the magnet 5e 'generates only an attractive force. In the invention according to claim 5, the Z of the moving stage 4 is
The first control means 30 receives the measurement value from the first measurement means 6 which outputs the measurement value according to the movement amount in the direction and the rotation amount in the α direction and the β direction, and the first control means 30 causes the first electromagnet groups 2a and 2b. ,
The currents applied to 2c, 2d, 2e, and 2f are controlled. According to the sixth aspect of the invention, the measurement value is output from the second measurement unit 7 that outputs the measurement value according to the movement amount of the moving stage 4 in the X and Y directions and the rotation amount of the θ direction, and The second control means 30 controls the cross current I5, I6 or the second electromagnet group 2
The currents I3 and I4 of b, 2c and 2e are controlled. Claim 7
In the invention described in (1), the second control means 30 receives the measurement values from the second measurement means 3 and 7, and the second control means 30 includes the first electromagnet group 2a of the electromagnets attached to the fixed stage 1 or the movable stage 4. The electromagnets used as 2b, 2c, 2d, 2e, and 2f are selected, and the current direction of each selected electromagnet is set. In the invention according to claim 9, the second control means 3 receives the measurement values from the second measurement means 3 and 7.
0 selects an electromagnet used as the second electromagnet group 2b, 2c, 2e from the electromagnets attached to the fixed stage 1 or the moving stage 4, and sets the direction of the current of each electromagnet.

[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 6 show a first embodiment of a magnetic levitation stage according to the present invention. In this embodiment, as shown in FIG. 1, the three axes of the Cartesian coordinate system are represented by X, Y, and Z, respectively.
The rotation angle around each axis is represented by α, β, and θ. Further, α is called pitching, β is rolling, and θ is yawing. FIG.
As shown in, a plurality of electromagnets 2 are arranged on the rectangular fixed stage 1. As shown in FIG. 2, this electromagnet 2
A coil 23 is wound around an axis in the Z direction, and the coil 22 is wound around an axis orthogonal to the axis of the coil 23, that is, an axis in the Y direction in FIG. . In FIG. 1, the parallel lines drawn in the square region showing each electromagnet 2 schematically represent the orientation of the coil 22 of each electromagnet 2. In this manner, the electromagnets 2 are arranged in a matrix in which the axes of the coils 22 are oriented in the X direction and those oriented in the Y direction. As shown in FIG. 3, the Hall element 3 is attached between the adjacent electromagnets 2 so as to project above the upper surface of the coil 22.

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.
Also, as shown in FIG. 4, permanent magnets 5a, 5b, 5c, 5d, 5e, and 5f are provided on the lower surface of the moving stage 4. Of these, the permanent magnets 5a, 5d, and 5f are attached with the N pole facing downward and the permanent magnets 5b, 5c, and 5e with the S pole facing downward in FIG. The moving stage 4 and the fixed stage 1 are provided on the lower surface of the moving stage 4.
Three gap sensors 6 for measuring the gap between and are attached. Moving stage 4 with three gap sensors
The amount of movement in the Z direction and the amounts of rotation in the pitching α direction and the rolling β direction are measured.

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 direction and the rotation amount of the yawing 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. The electromagnet 2d includes a core 21d, a coil 22d, and a coil 23d, and the electromagnet 2c includes a core 21c and a coil 22c.
And the coil 23c, the electromagnet 2e includes the core 21e, the coil 22e and the coil 23e, and the electromagnet 2f includes the core 21e.
f, the coil 22f, and the coil 23f, respectively. Further, the permanent magnet 5d is the electromagnet 2d, the permanent magnet 5c is the electromagnet 2c, and the permanent magnet 5e is the electromagnet 2e.
And the permanent magnet 5f faces the electromagnet 2f.

In FIG. 3, the coil 23d of the electromagnet 2d
A current I1 flowing in a clockwise direction when viewed from below. Therefore, the upper side of the electromagnet 2d (core 21d) is N
Since it is a pole, a repulsive force is generated between the permanent magnets 5d (the lower side is the N pole) facing each other. A current I2 in the clockwise direction when viewed from below also flows through the coil 23f of the electromagnet 2f,
A repulsive force is similarly generated between the electromagnet 2f and the permanent magnet 5f facing it.

In FIG. 3, the coil 23c of the electromagnet 2c
A current I3 flowing in a clockwise direction as viewed from below. Therefore, since the upper side of the electromagnet 2c has the N pole,
An attractive force is generated between the opposing permanent magnets 5c (the lower side is the S pole). A current I4 in the clockwise direction when viewed from below flows in the coil 23e of the electromagnet 2e, and an attractive force is similarly generated between the electromagnet 2e and the permanent magnet 5e facing the electromagnet 2e.

Electromagnets 2d, 2 facing each other in this way
Since a magnetic repulsive force or attractive force is generated between c, 2e and 2f and the permanent magnets 5d, 5c, 5e and 5f, coils 23d, 23c, 23e of these electromagnets 2d, 2c, 2e and 2f and By controlling the direction and strength of the current flowing through 23f, the movement of the moving stage 4 in the Z direction, the rotation in the α direction, and the rotation in the β direction can be controlled.

As described above, the coil 23c of the electromagnet 2c
A current I3 flows through the magnet and an attractive force is generated between the electromagnet 2c and the permanent magnet 5c. In this state, the coil 22
A current I5 in the counterclockwise direction when viewed from the Y direction flows through c. Therefore, in the portion of the coil 22c above the core 21c, the current I5 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 5c. That is, the movable stage 4 (permanent magnet 5c) applies a force Fc of the same magnitude in the opposite direction (to the left) to this fixed force (electromagnet 2).
You will receive from c). The direction and magnitude of the force Fc1 received by the moving stage 4 can be controlled by the direction and magnitude of the current I5 flowing through the coil 22c. Further, by increasing or decreasing the current I3 flowing through the coil 23c, it is possible to control Fc1 by changing the attractive force between the electromagnet 2c and the permanent magnet 5c (by changing the magnetic flux density).

On the other hand, as described above, the coil 2 of the electromagnet 2e
A current I4 flows through 3e, and an attractive force is generated between the electromagnet 2e and the permanent magnet 5e. In this state, when a counterclockwise current I6 is further applied to the coil 22e, a force Fe1 is applied to the moving stage 4 in the direction toward the back of the drawing by the same principle as described above. Force Fe received by the moving stage 4
1 can be similarly controlled by the current I6 flowing through the coil 22e and the current I4 flowing through the coil 23e.

FIG. 5 shows permanent magnets 5a, 5b, 5c, 5d,
The forces 5e and 5f receive from the fixed stage 1. The permanent magnet 5a is an electromagnet 2a (not shown), the permanent magnet 5b is an electromagnet 2b (not shown), and the permanent magnet 5c is an electromagnet 2c.
The permanent magnet 5d faces the electromagnet 2d, the permanent magnet 5e faces the electromagnet 2e, and the permanent magnet 5f faces the electromagnet 2f. The magnets 5a, 5d, and 5f receive the forces (repulsive forces) Fa, Fd, and Ff in the Z direction, and the permanent magnets 5b and 5f.
c and 5e are Z-direction forces (suction forces) Fb2 and Fc, respectively.
2, receive Fe2. These forces are generated by the electromagnets 2a, 2b,
2c, 2d, 2e, 2f coils 23a, 23b, 23
It is controlled by the currents flowing through c, 23d, 23e and 23f. Further, the permanent magnets 5b, 5c, and 5e have a force Fb1 in the X direction, a force Fc1 in the Y direction, and a force Fe1 in the X direction, respectively.
Receive. These forces Fb1, Fc1 and Fe1 are controlled by the currents flowing through the coils 22b, 22c, 22e, 23b, 23c and 23e.

From the state shown in FIG. 5, the moving stage 4 is moved to the electromagnet 2.
Of the electromagnet 2 facing the permanent magnets 5b, 5c, and 5e when moved in the X direction or the Y direction by the pitch of
Each of the two directions changes by 90 degrees. Therefore, the directions of the forces Fb, Fc, Fe received by the permanent magnets 5b, 5c, 5e also change by 90 degrees.

As shown in FIG. 6, 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 detect the permanent magnet 5a,
The positions and magnetic poles of b, c, d, e, and f are measured, and the control device 30 receiving this information determines the coil through which the current flows and the direction of the current. 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. The three gap sensors 6 measure the gap between the moving stage 4 and the fixed stage 1,
The control device 30 which has received this information controls the intensity of the current. As a result, the amount of movement of the moving stage 4 in the Z direction and the amounts of rotation in the α and β directions are controlled. Furthermore, the three laser interferometers 7 measure the X-direction and Y-direction movement amounts and the θ-direction rotation amount of the moving stage 4, and the control device 30 receiving this information determines the coil through which the current flows, and
Controls the direction and strength of the current. 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. However, instead of the laser interferometer,
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, but the Hall element 3 is omitted and the movement measured by the laser interferometer 7 is performed. The electromagnet selection and the current direction can be determined from the movement amount of the stage 4 in the X and Y directions and the rotation amount in the θ direction.

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 and an electromagnet may be provided on the moving stage, or an electromagnet may be provided on both stages. However, when the permanent magnet is provided on the moving stage as in the present embodiment, wiring to the moving stage is unnecessary. In addition, there is an advantage that the moving stage is lightened.

In the above description, only the case where the permanent magnet and the electromagnet face each other has been described. However, in the state where the permanent magnet and the electromagnet 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, in the first embodiment, the electric current is supplied only to the electromagnet facing the permanent magnet, but the force is applied to the moving stage by using another electromagnet provided within the range where the magnetic flux of the permanent magnet reaches. You may add it.

In the first embodiment, the permanent magnets 5b, 5
Although c and 5e 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 23b, 23c, and 23e (an attraction force is generated), and the current is passed through the coils 22b, 22c, and 22e, so that the coils move as in 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 first embodiment, the case where the moving stage that floats above the fixed stage is driven has been described. However, the moving stage floats below the fixed stage due to the suction force between the fixed stage and the moving stage. You may do it.

The permanent magnets 5a, 5b, 5 of the first embodiment
c, 5d, 5e, and 5f form a first magnet group of the magnetic levitation type stage according to the present invention, and the permanent magnets 5b, 5c, 5e form a second magnet group of the magnetic levitation type stage according to the present invention. The electromagnets 2a, 2d, 2c of the first embodiment,
Reference numerals 2d, 2e, and 2f form a first electromagnet group of the magnetic levitation type stage according to the present invention, and electromagnets 2b, 2c, and 2e form a second electromagnet group of the magnetic levitation type stage according to the present invention.

Second Embodiment FIGS. 7 and 8 show a second embodiment of the magnetic levitation type stage according to the present invention. Hereinafter, description will be made focusing on differences from the first embodiment, and the same portions will be denoted by the same reference numerals and the description thereof will be omitted. As shown in FIG. 7, permanent magnets 5a ', 5b', 5c are provided on the moving stage 4'of the second embodiment.
′, 5d ′, 5e ′, 5f ′, 5g ′ are attached. Of these, permanent magnets 5a ', 5d', 5f ', 5g'
Is attached with the N pole facing downward, and the permanent magnets 5b ', 5c', 5e 'are attached with the S pole facing downward.

The permanent magnet 5a 'has an electromagnet 2a (not shown), and the permanent magnet 5b' has an electromagnet 2b (not shown).
However, the permanent magnet 5c 'has the electromagnet 2c and the permanent magnet 5d'.
To the permanent magnet 5e ', and the electromagnet 2e to the permanent magnet 5e'.
An electromagnet 2f faces the permanent magnet 5f ', and an electromagnet 2g (not shown) faces the permanent magnet 5g'. Only the coil 23a in the electromagnet 2a, only the coil 23d in the electromagnet 2d, only the coil 23e in the electromagnet 2e,
The electromagnet 2f supplies currents only to the coil 23f. Further, in the electromagnet 2b, the coils 22b and 23
b, currents are supplied to the coils 22c and 23c in the electromagnet 2c, and to the coils 22e and 23e in the electromagnet 2e.

FIG. 8 shows permanent magnets 5a ', 5b', 5c ',
5d ', 5e', 5f ', 5g' show the force received. The permanent magnet 5a 'applies the repulsive force Fa' in the Z direction to the permanent magnet 5d.
′ Receives the repulsive force Fd ′ in the Z direction, and the permanent magnet 5f ′ receives the repulsive force Ff ′ in the Z direction. The permanent magnet 5b 'applies the force Fb1' in the X direction and the attraction force Fb2 'in the Z direction,
The permanent magnet 5c 'exerts a force Fc1' in the Y direction and an attraction force Fc2 'in the Z direction, and the permanent magnet 5g' exerts a force Fg1 'in the Y direction.
And a Z-direction attraction force Fg2 ′, respectively. Further, the permanent magnet 5e 'receives the attractive force Fe' in the Z direction. As described above, in the second embodiment, the permanent magnet 5e 'that receives only the attractive force Fe' is provided. Incidentally, in the first embodiment, all the permanent magnets that receive the attractive force also receive the Lorentz force in the horizontal plane.

As described above, by adding the permanent magnet for generating only the attractive force, the control characteristic of the moving stage 4'in the Z direction can be made excellent. For example, a permanent magnet (permanent magnet 5e 'in the second embodiment) that produces only an attractive force is used only for coarse movement in the Z direction, and the permanent magnet 5a is used.
By making ‘5d’ and 5f ′ dedicated to fine movement, it is possible to maintain high positioning accuracy without sacrificing drive speed. In addition, permanent magnets 5a ', 5d that generate repulsive force
By arranging the permanent magnets 5e ′ that generate only attractive force on the outer sides of the 5 ′ and 5f ′, respectively, near the center of the moving stage, stable control of the posture of the moving stage becomes easy.

In the second embodiment, the case where a permanent magnet is used as a magnet that generates only an attractive force has been described. However, instead of the permanent magnet, a material (magnetic material) that generates an attractive force between the opposing electromagnets is used. Material) can be used.

The permanent magnets 5a ', 5b' of the second embodiment,
Reference numerals 5c ', 5d', 5e ', 5f', and 5g 'denote the first magnet group of the magnetic levitation stage according to the present invention, and the permanent magnet 5b.
′, 5c ′ and 5e ′ respectively constitute the second magnet group of the magnetic levitation type stage according to the present invention. Permanent magnet 5e '
Constitutes the "magnet that produces only an attractive force" of the magnetic levitation stage according to the present invention. Electromagnet 2 of the second embodiment
Reference numerals a, 2d, 2c, 2d, 2e, and 2f denote the first electromagnets of the magnetic levitation stage according to the present invention.
2e respectively constitute the second electromagnet group of the magnetic levitation type stage according to the present invention.

-Third Embodiment- Hereinafter, a third 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. 9, a plurality of electromagnets 102 are arranged in a matrix on a rectangular fixed stage 101. As shown in FIG. 10, this electromagnet 10
Reference numeral 2 denotes a rectangular parallelepiped core 121, a high-permeability member 122 overlaid on the core 121, and Z passing through the core 121.
The coil 123 wound around the axis of the direction and the core 1
A coil 12 wound around an axis in the Y direction passing through 21.
4 and a coil 125 wound around an axis in the X direction passing through the core 121. As shown in FIG. 12, the Hall element 3 is attached between the adjacent electromagnets 102.

As shown in FIGS. 9 and 11, permanent magnets 105a, 105b, 1 are provided on the lower surface of the moving stage 104.
05c, 105d, 105e are provided. Of these, the permanent magnets 105a, 105c, 105e are attached with the N pole facing downward, and the permanent magnets 105b, 105d are mounted with the S pole facing downward.

Next, the driving principle of the magnetic levitation type stage of the third embodiment having the above structure will be described with reference to FIG. The permanent magnet 105a is the electromagnet 102a, the permanent magnet 105b is the electromagnet 102b, the permanent magnet 105c is the electromagnet 102c, and the permanent magnet 105d is the electromagnet 102d.
And are facing each other. In FIG. 12, the electromagnet 10
A current I1 in the clockwise direction when viewed from below flows in the coil 123a of 2a. Therefore, the electromagnet 102a
Since the upper side of the (core 121a) has the N pole, a repulsive force is generated between the opposing permanent magnet 105a (the lower side has the N pole). A current I2 in the counterclockwise direction when viewed from below flows in the coil 123d of the electromagnet 102d.
2d and a permanent magnet 105d facing it (the lower side is S
Similarly, repulsion occurs between the poles.

In FIG. 12, the coil 1 of the electromagnet 102b
A current I3 flows clockwise in 23b when viewed from below. Therefore, the electromagnet 102b (core 121
In b), since the upper side is the N pole, the opposing permanent magnets 105
An attractive force is generated between the electrode and b (the S pole is on the lower side). Electromagnet 10
A current I4 in the counterclockwise direction when viewed from below flows in the coil 123c of 2c, and an attractive force is similarly generated between the electromagnet 102c and the permanent magnet 105c (N pole on the lower side) facing the electromagnet 102c.

As described above, the coil 1 of the electromagnet 102b
A current I3 flows through 23b and the electromagnet 102b and the permanent magnet 1
A suction force is generated between 05b. In this state, when a current I5 in the clockwise direction when viewed from the right is further passed through the coil 125b, the moving stage 104 receives the force Fb1 in the left direction as described in the first embodiment.

On the other hand, as described above, the current I4 flows through the coil 123c of the electromagnet 102c, and the attractive force is generated between the electromagnet 102c and the permanent magnet 105c. In this state, when a current I6 in the clockwise direction when viewed from the right direction is further applied to the coil 125c, the moving stage 4 receives a force F in the right direction.
Receive c1. When a counterclockwise current I7 is passed through the coil 124c, the moving stage 4 receives a force Fc2 in a direction from the front side to the back side of the paper surface.

FIG. 13 shows the force applied to the moving stage 104. The permanent magnet 105e is the electromagnet 102 (not shown).
It faces e. Permanent magnets 105a, 105d, 10
5e is a force (repulsive force) Fa, Fd, Fe in the Z direction.
In response, the permanent magnets 105b and 105c receive Z-direction forces (attraction forces) Fb3 and Fc3. In addition, the permanent magnet 105
b is X due to the current of the coil 125b of the electromagnet 102b.
The force Fb1 in the direction and the force Fb2 in the Y direction are respectively received by the current of the coil 124b. The permanent magnet 105c applies a force Fc1 in the X direction by the current of the coil 125c of the electromagnet 102c and a force F in the Y direction by the current of the coil 124c.
Receive c2 respectively. Since the electromagnet 2 includes the coil 124 and the coil 125 as described above, it is possible to simultaneously apply forces in the X direction and the Y direction to one permanent magnet. Even if the moving stage 104 moves beyond the pitch of the electromagnets 2 and the electromagnets facing the permanent magnets 105b and 105c change, the permanent magnets 105b and 105c.
The direction of the force that can be applied to c is not limited.

In the third embodiment, the electromagnet 2 has three coils wound around axes in the X, Y and Z directions, respectively. Therefore, the magnetic attraction force, repulsive force, and Lorentz force 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 as compared with the first embodiment. 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 first aspect of the present invention, the moving stage is levitated by the repulsive force or the attractive force of the magnet, and the Z-direction moving amount and the α-direction and β-direction rotating amounts are controlled to flow in the magnetic flux. Since the amount of movement in the X and Y directions and the amount of rotation in the θ direction are controlled by the electric current, it is possible to accurately position the moving stage without generating dust. Further, since the moving stage can be driven without using air, it can be used even in a vacuum.
According to the third aspect of the invention, the electromagnet is provided with three coils wound around the X, Y, and Z axes, so that the attraction force, repulsion force, and Lorentz force between the magnets are moved. It can be effectively used regardless of the position, and the number of permanent magnets on the moving stage can be reduced. Therefore,
The moving stage becomes lightweight and high speed driving becomes possible. In the invention described in claim 4, since the magnet that contributes only to the attraction force is provided, for example, the electromagnets that control the coarse movement and the fine movement in the Z direction can be separated into different electromagnets, and the high speed control of the Z direction is possible. It is possible to achieve both high-precision positioning and. Further, when the magnet that contributes only to the attraction force is provided near the center of the moving stage, the control of the moving stage becomes more stable. According to the invention described in claims 5 to 10, since the measurement means for measuring the posture of the moving stage and the control means for controlling the electromagnet used by receiving the measurement value of the measurement means and the current supplied to the electromagnet are provided, The moving stage is smoothly controlled. According to the twelfth aspect of the present invention, since the moving stage is provided with the permanent magnets and the fixed stage is provided with the electromagnets, wiring to the moving stage is unnecessary, and the moving stage is lightened. Further, the electromagnet can be cooled easily.

[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.

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

FIG. 6 is a control block diagram of the moving stage of the first embodiment.

FIG. 7 is a bottom view of the moving stage according to the second embodiment.

8 is a bottom view of the moving stage showing the force received by the moving stage of FIG. 7. FIG.

FIG. 9 is a perspective view showing a third embodiment of the magnetic levitation type stage according to the present invention.

FIG. 10 is a perspective view showing an electromagnet of a third embodiment.

FIG. 11 is a bottom view showing the moving stage of the third embodiment.

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

13 is a bottom view of the moving stage showing a force received by the moving stage of FIG. 11. FIG.

[Explanation of symbols]

 1 Fixed Stage 2 Electromagnet 3 Hall Element 4 Moving Stage 5 Electromagnet 6 Gap Sensor 7 Laser Interferometer 23 Coil 24 Coil 30 Control Device 102 Electromagnet 123 Coil 124 Coil 125 Coil I5 Transverse Current I6 Transverse Current I7 Transverse Current

Claims (12)

[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. A magnetic levitation type stage having a movable stage driven to the position of 1), a first magnet group provided on one of the movable stage and the fixed stage, and a first electromagnet group provided on the other stage. A moving force in the Z direction and a rotating force in the α direction and the β direction by a repulsive force or a suction force between the second stage and the second stage. In the magnetic flux created between the second electromagnet group and the electric field provided in the other stage, a transverse current flowing in the electric wire provided in the other stage applies a moving force in the X and Y directions and a rotational force in the θ direction to the moving stage. Special to grant Magnetic levitation type stage to be. 2. Each electromagnet of the second electromagnet group includes a first coil wound around an axis in the Z direction and an X or Y coil.
The magnetic levitation type stage according to claim 1, further comprising a second coil wound around an axis of the direction, wherein the transverse current is passed through the second coil. 3. Each electromagnet of the second electromagnet group includes a first coil wound around an axis in the Z direction and an X or Y coil.
A second coil wound around an axis of direction, and a third coil wound around an axis orthogonal to both the Z direction and the axial direction of the second coil, The magnetic levitation stage according to claim 1, wherein the transverse current is passed through the second coil and / or the third coil. 4. The moving stage is driven on the fixed stage, and the first magnet group includes magnets that generate only an attractive force. The magnetically levitated stage according to the item. 5. A first measuring unit which is attached to the movable stage or the fixed stage and outputs a measured value according to the amount of movement of the movable stage in the Z direction and the amount of rotation in the α direction and β direction, In response to the measured value from one measuring means, the first
The magnetic levitation stage according to any one of claims 1 to 4, further comprising: a first control unit that controls a current flowing through the electromagnet group. 6. A second measuring unit that outputs a measured value according to an amount of movement of the moving stage in the X and Y directions and a amount of rotation of the θ direction, and the measured value from the second measuring unit. Second control means for receiving and controlling the transverse current and / or the current of the second electromagnet group.
6. The magnetic levitation type stage according to any one of 5 to 10. 7. A second measuring unit that outputs a measured value according to an amount of movement of the moving stage in the X and Y directions and a amount of rotation of the θ direction, and the measured value from the second measuring unit. A second control means for receiving and selecting an electromagnet to be used as the first electromagnet group among the electromagnets attached to the fixed stage or the movable stage, and for setting a current direction of each of the selected electromagnets; Claim 1-5 characterized by the above-mentioned.
The magnetic levitation type stage according to any one of 1. 8. The magnetic levitation type stage according to claim 7, wherein the second measuring means is a Hall element attached to the fixed stage or the movable stage. 9. A second measuring unit that outputs a measured value according to an amount of movement of the moving stage in the X and Y directions and an amount of rotation of the θ direction, and the measured value from the second measuring unit. Second control means for receiving and selecting an electromagnet to be used as the second electromagnet group among the electromagnets attached to the fixed stage or the movable stage, and setting the direction of the current of each selected electromagnet. Claim 1 characterized by
5. The magnetic levitation stage according to any one of 5 above. 10. The magnetic levitation stage according to claim 9, wherein the second measuring unit is a Hall element attached to the fixed stage or the movable stage. 11. The first magnet group, the second magnet group, the first electromagnet group, or the second electromagnet group is made of a superconducting material. The magnetic levitation stage according to any one of 1 to 10. 12. 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.