JP2010109224A - Stage device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a stage device having an own-weight support device with a simple structure, obviating the need to supply energy thereto, and without causing component deterioration. <P>SOLUTION: This stage device includes: a table 1; a drive part 6 moving the table 1; and the own-weight support device supporting the own weight of the table against the gravity. The own-weight support device comprises: first permanent magnets 7 each magnetized in the axial direction and each having a columnar shape having magnetic poles at both tips; and second permanent magnets 8 each having a through-hole 9 and each magnetized so that a nearly-uniform magnetic field in parallel with the axial direction of the through-hole 9 is generated in a certain range in the through-hole 9. One-side tip of the first permanent magnet 7 is inserted in the through-hole 9 formed on the second permanent magnet 8 without contacting it. The other-side tip of the first permanent magnet 7 is arranged to be located outside the through-hole 9 formed on the second permanent magnet 8. Magnetic force generated between the first permanent magnet 7 and the second permanent magnet 8 is used as supporting force. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  An aspect of the present invention generally relates to a stage apparatus that holds a substrate on a table and performs vertical positioning thereof, and particularly relates to a stage apparatus suitable for a semiconductor manufacturing apparatus, a semiconductor inspection apparatus, a liquid crystal manufacturing apparatus, or the like.

In a semiconductor manufacturing apparatus, a semiconductor inspection apparatus, a liquid crystal manufacturing apparatus, etc., a stage apparatus is required for holding a substrate such as a semiconductor wafer or a glass substrate inside the apparatus and accurately positioning the substrate.
As such a stage device, for example, a scanning operation and a step operation in a wafer inspection apparatus that perform a horizontal operation and positioning, as well as a vertical operation, that is, a Z-direction operation and positioning for purposes such as focusing There is something to do. There is also an apparatus in which both are integrated.
As a driving method for realizing the vertical operation of the stage device, various methods such as a method using an electromagnetic motor are employed. (For example, refer to Patent Document 1.)
Normally, gravity is applied vertically downward to a table, a mounting board, etc., and therefore the vertical drive unit must always generate a force against this gravity regardless of the operating state of the table. . This means that it is necessary to keep a constant current flowing even when the electromagnetic motor is a vertical drive unit, even when it is stationary. It has been pointed out that there are problems such as adverse effects (Patent Document 3).
As a countermeasure against such a problem, for example, as seen in Patent Document 2, in addition to a drive unit composed of an electromagnetic motor or the like, a self-weight support device using an air cylinder or the like is separately provided. However, in order to provide a constant weight support force regardless of the vertical table position change, it is necessary to provide a control mechanism for the internal pressure of the air cylinder, which causes problems that the mechanism is complicated and the cost is increased.
In the same document, an example using a permanent magnet in addition to an air cylinder is introduced. However, since the attractive force and repulsive force of the permanent magnet change according to the distance between the permanent magnets, the table in the vertical direction is used. In order to keep the supporting force constant even if the position changes, it is necessary to provide a separate control mechanism.

As another countermeasure, for example, as shown in Patent Document 3, a support device that can obtain a substantially constant support force regardless of the table position in the vertical direction by combining a permanent magnet and a leaf spring is introduced. ing. In this case, a control mechanism for keeping the supporting force constant is unnecessary, but the force between the permanent magnets is inversely proportional to the square of the distance, whereas the force of the leaf spring is proportional to the displacement of the table. It is impossible to make the force obtained by combining the two completely constant, and it is inevitable that the force slightly varies according to the change in the table position in the vertical direction. Further, since the deformation of the leaf spring is used, if the leaf spring is deteriorated due to long-term use, the support force may greatly fluctuate.
JP 2007-123860 A (FIG. 2) JP 2006-140399 A (FIG. 3) JP-A-10-521 Japanese Examined Patent Publication No. 60-34248 (Fig. 2) Japanese Patent No. 2799948 (FIG. 2)

  An aspect of the present invention has been made to solve the above-described problem. A substantially constant support force is applied to the table regardless of a change in the position of the table, the structure is simple, and deterioration of the component parts is caused. To provide a stage device having a self-weight support device that does not occur.

In order to achieve the above object, according to an embodiment of the present invention,
A table for holding the substrate;
A drive unit for moving the table;
A self-weight support device that applies a force of substantially constant magnitude to the table and supports the weight of the table against gravity;
A stage device comprising:
The self-weight support device is
A first permanent magnet which is magnetized in the axial direction and has a column shape having magnetic poles at both ends;
A second permanent magnet having a through hole and magnetized so that a substantially uniform magnetic field parallel to the axial direction of the through hole is generated in a certain range inside the through hole;
One end of the first permanent magnet is inserted in a non-contact manner into the through hole formed in the second permanent magnet, and is disposed so as to be positioned within the range of the substantially uniform magnetic field. ,
The other tip of the first permanent magnet is disposed outside the through hole formed in the second permanent magnet,
By being a self-weight support device that uses the magnetic force generated between the first permanent magnet and the second permanent magnet as a support force,
Although it has a simple structure in which permanent magnets are combined, it is possible to give a substantially constant support force to the table regardless of the position of the table in the vertical direction without supplying any energy from the outside.

According to a preferred embodiment of the present invention,
By using the first permanent magnet as a combination of a plurality of permanent magnets, the self-weight support device can have an appropriate shape according to the structure of the stage device.

According to a preferred embodiment of the present invention,
By using the second permanent magnet as a combination of a plurality of permanent magnets, the self-weight support device can have an appropriate shape according to the structure of the stage device.
Furthermore, by appropriately adjusting the shapes of the plurality of permanent magnets and their magnetization directions, it is possible to improve the utilization efficiency of the generated magnetic field and to reduce the overall shape of the second permanent magnet. .

According to another embodiment of the present invention,
A table for holding the substrate;
A drive unit for moving the table;
A self-weight support device that applies a force of substantially constant magnitude to the table and supports the weight of the table against gravity;
A stage device comprising:
The self-weight support device is
First, second, and third permanent magnets that are magnetized in the axial direction and have a column shape having magnetic poles at both ends;
The fourth and fifth permanent magnets have a through hole and are magnetized so that a substantially uniform magnetic field parallel to the axial direction of the through hole is generated in a certain range inside the through hole. ,
The first and second permanent magnets are arranged so that they are parallel to each other and their magnetization directions are opposite to each other,
The fourth and fifth permanent magnets are arranged so that substantially uniform magnetic fields generated in the respective through holes are parallel and opposite to each other.
One end of the first permanent magnet is inserted in a non-contact manner into the through hole formed in the fourth permanent magnet, and is disposed so as to be positioned within the range of the substantially uniform magnetic field. ,
The other tip of the first permanent magnet is arranged to be located outside the through hole formed in the fourth permanent magnet,
One end of the second permanent magnet is inserted in a non-contact manner into the through hole formed in the fifth permanent magnet, and is disposed so as to be positioned within the range of the substantially uniform magnetic field. ,
The other end of the second permanent magnet is arranged to be located outside the through hole formed in the fifth permanent magnet,
Among the first permanent magnets, a tip located outside the through hole formed in the fourth permanent magnet;
Of the second permanent magnet, a tip located outside the through hole formed in the fifth permanent magnet,
Connected via the third permanent magnet,
Self-weight that uses the magnetic force generated between the first permanent magnet and the fourth permanent magnet and the magnetic force generated between the second permanent magnet and the fifth permanent magnet as a supporting force. By using a support device,
It is possible to further improve the uniformity of the support force received by the table without increasing the size of the self-weight support device.

  According to a preferred aspect of the present invention, at least one of the fourth and fifth permanent magnets is a stage device formed by combining a plurality of permanent magnets.

  According to a preferred aspect of the present invention, at least one of the first and second permanent magnets is a stage device formed by combining a plurality of permanent magnets.

  According to a preferred aspect of the present invention, the third permanent magnet is a stage device formed by combining a plurality of permanent magnets.

According to the aspect of the present invention, there is an effect that a substantially constant self-weight support force independent of the table position in the vertical direction can be given to the table without providing a separate control mechanism.
Further, since the supporting force is based on a permanent magnet and does not require any energy supply or control from the outside, the structure of the self-weight supporting device can be simplified.
Furthermore, the self-weight support device constituting the present invention does not involve physical deformation such as a leaf spring, but uses non-contact force acting between the permanent magnets, so that deterioration of components occurs. And can be used for a long time.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a perspective view showing an example of a stage apparatus according to an embodiment of the present invention. FIG. 2 is a sectional view showing the internal structure of the stage apparatus shown in FIG.
The stage apparatus shown in both figures has a circular table 1 for mounting a substrate. A table base 2 is disposed below the table 1, and the table 1 and the table base 2 are fixed by a vacuum suction means (not shown), and both are integrated.
An air movable element 3 having a hollow rectangular cross section is fixed to the lower part of the table base 2.

An air stator 4 having a hollow rectangular cross section is disposed so as to surround the air mover 3, and the air stator 4 is fixed to the base plate 5.
Each of the air movable element 3 and the air stator 4 is made of alumina ceramics, and these are opposed to each other through a gap of about 5 μm. Since a static pressure gas bearing (not shown) is formed on each of the opposing surfaces, the air mover 3 and the air stator 4 are smoothly fitted in a non-contact state.

With such a structure, the table 1, the table base 2, and the air movable element 3 can be moved up and down with respect to the air stator 4 and the base plate 5.

The reason why both the air mover 3 and the air stator 4 have a rectangular cross section is to limit the degree of freedom in the rotation direction of the air mover 3. When it is necessary to drive the table 1 also in the rotation direction, a mechanism for rotating the base plate 5 itself may be provided.
A driving unit that applies a driving force to the table 1 is a linear motor 6 including a coil 6a and a motor permanent magnet 6b. The coil 6 a is fixed to the center of the upper surface of the base plate 5, and the motor permanent magnet 6 b is fixed to the inner wall of the air mover 3. A driving force is generated between the coil 6a and the motor permanent magnet 6b by supplying current to the coil 6a from outside via a cable (not shown).

Next, a self-weight support device using a permanent magnet, which is a component in one embodiment of the present invention, will be described.
At four locations near the outer periphery of the lower surface of the table base 2, N extremes of the rod-shaped permanent magnet 7 having a cylindrical shape are fixed by the tip fixture 10, and each S extreme protrudes vertically downward with respect to the table base 2. ing.

Further, ring-shaped permanent magnets 8 having a through hole 9 at the center are fixed at four locations on the base plate 5. The ring-type permanent magnets 8 are magnetized in the direction parallel to the through-holes 9 and are all arranged with their north poles facing upward and the center axes of the respective rod-type permanent magnets 7 disposed above each. ing.

Further, the lower end (S pole) of each bar-type permanent magnet 7 is inserted into the through hole 9 of each ring-type permanent magnet 8, and each bar-type when the table 1 is at the center of the stroke in the vertical direction. The lower end of the permanent magnet 7 is designed to be positioned at the center of the ring-type permanent magnet 8 in the height direction.

Here, as described in Patent Document 4, at least near the center of the through hole 9 formed along the magnetization direction of the ring-type permanent magnet 8, it is substantially uniform along the magnetization direction. There is a magnetic field.

In this embodiment, a ring-type permanent magnet 8 made of a neodymium magnet having a height of 40 mm, a diameter of 50 mm, a diameter of the through hole 9 of 16 mm, and a residual magnetic flux density of about 1200 mT is used. In this ring-type permanent magnet 8, the magnetic flux density along the central axis inside the through hole 9 is plotted along the height direction position as shown in FIG. 3. According to the figure, it can be seen that a magnetic field that can be regarded as being substantially uniform is formed within a range of about ± 10 mm around the position of the height of 20 mm, which is the center of the ring-type permanent magnet 8.

When one end of the rod-shaped permanent magnet 7 is arranged near the center of the through hole 9, the rod-shaped permanent magnet 7 receives a force from the magnetic field, but the magnitude of the force is proportional to the magnitude of the magnetic field. Therefore, as long as the tip of the rod-shaped permanent magnet 7 is within the range in which the magnetic field is substantially uniform in the through hole 9 of the ring-shaped permanent magnet 8, the force received by the rod-shaped permanent magnet 7 is the position in the height direction. Regardless, it is almost constant.
When the residual magnetic flux density of the rod-shaped permanent magnet 7 is 1200 mT and the diameter is 10 mm, the force received by one rod-shaped permanent magnet 7 is about 23N. Since this force is proportional to the cross-sectional area of the rod-shaped permanent magnet 7, in the actual design, the cross-sectional area is determined according to the required support force.

In the present embodiment, the supporting force that requires the sum of the gravitational forces received by the substrate such as a wafer, the table 1, the table base 2, the air mover 3, the tip fixture 10, the rod permanent magnet 7, and the motor permanent magnet 6b. It is. Needless to say, if there is another component supported by the drive unit, the gravity applied to the component should be added to the necessary supporting force.

In the present embodiment, four sets of rod-type permanent magnets 7 and ring-type permanent magnets 8 are arranged, so that the magnitude of the force received by each bar-type permanent magnet 7 is the required support force. The cross-sectional area of the rod-shaped permanent magnet 7 is determined so as to be 1/4.

With the above configuration, at least in the stationary state, the driving unit hardly receives the gravitational force applied to the table 1 and the like, so that the current supplied to the coil 6a by the table 1 in the stationary state can be made substantially zero.

In the stage apparatus shown in FIGS. 1 and 2, FIG. 4 shows the result of calculating the relationship between the magnitude of the force received by each bar permanent magnet 7 and the position of the bar permanent magnet 7.
The horizontal axis indicates the position of the lower end of the rod-shaped permanent magnet 7, where 0 is the case where the lower end of the rod-shaped permanent magnet 7 is at the lower end of the ring-shaped permanent magnet 8, and the upward direction is the + direction.

In the same figure, it is shown that the force received when the lower end of the rod-shaped permanent magnet 7 is near the center of the ring-shaped permanent magnet 8 is substantially constant, but as a whole, it tends to be slightly downward. ing. For this reason, the support force slightly varies depending on the height of the table 1 in the vertical direction.

The cause of this problem and effective countermeasures are shown below.
It should be noted that even if there is such a downward-sloping tendency, as shown in FIG. 4, the tendency is slight, and the current supplied to the coil 6a is reduced by applying a substantially uniform force as a supporting force. The effect of the present invention is sufficiently obtained.

The ring-type permanent magnet 8 magnetized in the direction parallel to the through hole 9 forms a magnetic field not only inside the through hole 9 but also outside, and this external magnetic field is different from that inside the through hole 9. It is different and generally not uniform.

The rod-shaped permanent magnet 7 receives a force from the magnetic field formed by the ring-shaped permanent magnet 8, and this force is a resultant force of each force applied to both ends of the rod-shaped permanent magnet 7. The force received by the end of the ring-type permanent magnet 8 disposed inside the through hole 9 is substantially constant regardless of the position of the table 1 as described above, but the force received by the other end is Since the mold permanent magnet 8 is caused by a magnetic field (not uniform) formed outside, in the case of this embodiment, the upward force increases as the bar permanent magnet 7 is located downward.

The upper end of the rod-shaped permanent magnet 7 is small compared to the force received by the lower end of the rod-shaped permanent magnet 7 because the distance from the ring-shaped permanent magnet 8 is large, but it is not negligible. The result is as shown.

As a countermeasure, firstly, the length of the rod-shaped permanent magnet 7 is lengthened, and the upper end of the rod-shaped permanent magnet 7 is moved away from the ring-shaped permanent magnet 8. In order to investigate the influence of the force applied to the upper end of the rod-shaped permanent magnet 7, the magnitude of the force received by the entire rod-shaped permanent magnet 7 when the lower end of the rod-shaped permanent magnet 7 is arranged at the center of the ring-shaped permanent magnet 8, The relationship with the length of the rod-shaped permanent magnet 7 is shown in FIG. According to the figure, as the length of the rod-shaped permanent magnet 7 is shorter, the upper end of the rod-shaped permanent magnet 7 gets closer to the ring-shaped permanent magnet 8 and the force received by the upper end increases, so the upward force increases. ing. On the contrary, if the length of the rod-shaped permanent magnet 7 is increased, the force decreases as the upper end of the rod-shaped permanent magnet 7 moves away from the ring-shaped permanent magnet 8, and further decreases when the length is about 150 mm or more. do not do. This indicates that the force received by the upper end of the rod-shaped permanent magnet 7 is so small that it can be ignored.
That is, in this embodiment, by making the length of the bar-shaped permanent magnet 7 150 mm or more, the phenomenon of the lowering of the right shoulder in FIG. 4 is eliminated, and the force received by the bar-shaped permanent magnet 7 can be made constant. .
However, there are many cases where such measures cannot be taken due to restrictions on the space in which the stage device is arranged.

An example of a stage apparatus according to another embodiment of the present invention is shown in FIG. 6 as another measure for making the force received by each bar-type permanent magnet 7, that is, the supporting force more uniform.

6 is the same as the stage apparatus shown in FIGS. 1 and 2 in that four ring-type permanent magnets 8 are arranged on the base plate 5. However, in the stage apparatus shown in FIGS. 1 and 2, all the four ring-type permanent magnets 8 are arranged with the north pole facing upward, whereas in the stage apparatus of FIG. The permanent magnets 8 (8a, 8b) are arranged with the north pole facing upward, and the other two ring-type permanent magnets 8 (8c, 8d) are different in that they are arranged with the south pole facing upward. .

Further, the point that the rod-type permanent magnets 7 are inserted into the respective ring-type permanent magnets 8 is the same, but in the stage apparatus of FIG. 6, the ring-type permanent magnets 8 (8a, 8a, 8b), the rod-shaped permanent magnets 7 (7a, 7b) are arranged with the south pole facing downward, and the other rod-shaped permanent magnets 7 (7c, 7d) are arranged with the north pole facing downward. is doing.

As described above, the direction of the magnetic pole of each permanent magnet is partially different from that of the stage apparatus shown in FIGS. 1 and 2, but each bar-type permanent magnet 7 has a magnetic field of each ring-type permanent magnet 8. As in the case of the stage apparatus shown in FIG.

Further, in the stage apparatus of FIG. 6, one upper end of the rod-shaped permanent magnet 7 (7a, 7b) arranged with the south pole facing downward and the rod-shaped permanent magnet 7 (7c) arranged with the north pole facing downward. 7d) is connected to one upper end of the permanent magnet 11 through a horizontal bar permanent magnet 11.

The horizontal bar permanent magnet 11 is magnetized in the axial direction, and the cross-sectional shape thereof is the same as that of the bar permanent magnet 7. One upper end (N pole) of the rod-shaped permanent magnet 7 (7a, 7b) arranged with the S pole facing downward is connected in an adsorbed state with the S extreme of the horizontal rod-shaped permanent magnet 11, One upper end (S pole) of the bar permanent magnet 7 (7c, 7d) arranged with the N pole facing downward is connected to the N extreme of the horizontal bar permanent magnet 11 in an adsorbed state. In this arrangement, the two horizontal bar permanent magnets 11 are fixed to the table base 2 by horizontal fixing tools 12 respectively.

By arranging the horizontal bar permanent magnets 11, the total amount of so-called magnetic charges near the upper end of each bar permanent magnet 7 approaches zero. As a result, the force applied to the vicinity of the upper end of the rod-type permanent magnet 7 by the magnetic field formed outside the ring-type permanent magnet 8 can be made substantially zero.
That is, even if the length of the rod-shaped permanent magnet 7 is short, the tendency of downward sloping as shown in FIG. 4 does not appear, and a substantially constant support force can be obtained for the table 1.

The horizontal bar permanent magnet 11 does not have to be a single permanent magnet, and a plurality of permanent magnets may be connected with different polarities. In this case, the entire shape of the horizontal bar-type permanent magnet 11 does not have to be linear, and may be various shapes such as a V shape and a U shape depending on the relationship with other parts. .

An example of a stage apparatus according to another embodiment of the present invention is shown in FIGS. 7, 8, and 9. FIG.
FIG. 7 is a perspective view showing the entire stage apparatus according to this embodiment.
8 and 9 are cross-sectional views of the stage apparatus shown in FIG.

In the present embodiment, the circular table 1 is fixed to the table base 2, and the air movable element 3 is fixed to the lower part of the table base 2, and the static pressure gas bearing between the air movable element 4 and the surrounding air stator 4. 1 is the same as that of the stage apparatus shown in FIG. 1 in that it is smoothly fitted through the base plate 5 and the air stator 4 is fixed to the base plate 5.

On the other hand, the stage shown in FIG. 1 is such that the air mover 3 and the air stator 4 have a circular cross section and have a degree of freedom not only in the vertical direction but also in the rotational direction with respect to their relative movement. It is different from the device.

With this structure, the stage apparatus according to this embodiment can move in the vertical direction (Z direction) relative to the base plate 5 and can also operate in the rotational direction (θ direction). In order to realize the rotational movement of the table 1 in the embodiment shown in FIGS. 1 and 2, it is necessary to provide a mechanism for rotating the base plate 5 as described above. Therefore, a bearing for guiding the rotational movement of the base plate 5 is separately provided. It was necessary to install. On the other hand, this embodiment is advantageous in that it can be constituted by a single bearing comprising the air movable element 3 and the air stator 4.

On the lower surface of the table base 2, an N extreme of a rod-shaped permanent magnet 7 having a cylindrical shape is fixed by a tip fixture 10, and the S extreme protrudes vertically downward with respect to the table base 2.
A ring-type permanent magnet 8 having a through hole 9 at the center is fixed to the upper surface of the base plate 5. The ring-type permanent magnet 8 is magnetized in a direction parallel to the through hole 9 and is arranged with the north pole facing upward.

The lower end (S pole) of the rod-shaped permanent magnet 7 is inserted into the through hole 9 of the ring-shaped permanent magnet 8, and the lower end of the rod-shaped permanent magnet 7 when the table 1 is at the center of the stroke in the vertical direction. (S pole) is designed to be positioned at the center of the ring-shaped permanent magnet 8 in the height direction.
The central axis of the rod-type permanent magnet 7 and the central axis of the through hole 9 of the ring-type permanent magnet 8 coincide with the rotation axis of the table 1. For this reason, even if the table 1 rotates, the positional relationship between the rod-type permanent magnet 7 and the ring-type permanent magnet 8 does not change, and a constant support force can be applied to the table 1.

The driving unit that applies the driving force of the table 1 includes a Z driving unit 13 that applies a driving force in the vertical direction and a θ driving unit 14 that applies a driving force in the rotational direction.
The Z drive unit 13 is a linear motor including a Z coil 13 </ b> A fixed on the lower surface of the stage base and a Z permanent magnet 13 </ b> B fixed on the base plate 5.
The θ drive unit 14 is a linear motor including a θ coil 14 a fixed to the lower surface of the stage base and a θ permanent magnet 14 b fixed on the base plate 5.
Since any of the linear motors is not different from a conventionally used method, a detailed description of the arrangement of permanent magnets, the direction of coils, and the like is omitted.

In this embodiment, a substantially constant support force can be applied to the table 1 regardless of the vertical displacement of the table 1 by the self-weight support device constituted by the rod-type permanent magnet 7 and the ring-type permanent magnet 8. Therefore, when the table 1 is at least stationary, the current supplied to the Z coil 13A can be made substantially zero. This effect can be obtained regardless of the position of the table 1 in the rotational direction.

In each of the embodiments described above, the substrate mounting surface 1a of the table 1 is vertically upward, so that the supporting force that should be obtained in opposition to gravity is generated in the direction from the base plate 5 to the table 1. . The present invention is not limited to this, and can also be applied to a stage apparatus in which the substrate mounting surface 1a of the table 1 is vertically downward. In this case, for example, by setting the direction of the magnetic poles of all the ring-type permanent magnets 8 to be opposite to those of the respective embodiments, the supporting force can be set in the direction from the table 1 to the base plate 5, that is, vertically upward. . Such a configuration also belongs to the technical scope of the present invention.

In each of the embodiments described above, as described above, when the table 1 is at the stroke center position in the vertical direction, one tip of each bar-type permanent magnet 7 is at the height of each ring-type permanent magnet 8. Must be located in the center of direction.
In order to satisfy such a positional relationship, the length of each bar-type permanent magnet 7 needs to be appropriate, but the bar-type permanent magnet 7 does not need to be composed of a single permanent magnet. . It is also possible to adjust the overall length by connecting a plurality of rod-shaped permanent magnets 7 in series. In this case, as a method of connecting and fixing the rod-shaped permanent magnets 7, for example, a method of covering the entire rod-shaped permanent magnet 7 with a tube made of a nonmagnetic material such as aluminum is effective.

In each Example shown above, the single ring type permanent magnet 8 was employ | adopted as a permanent magnet which has the through-hole 9, However, You may comprise each ring type permanent magnet 8 as a combination of a some permanent magnet. . For example, in Patent Document 5, a plurality of permanent magnets are arranged, and the outer shape of each permanent magnet and the direction of magnetization are adjusted as appropriate so that a uniform magnetic field is generated inside the through hole 9 formed at the center. A cylindrical permanent magnet magnetic field generator that can be formed is introduced.
If such a cylindrical permanent magnet magnetic field generator is used in place of the ring permanent magnet 8 in each of the embodiments described above, the magnetic field formed by these permanent magnets can be reduced.

Further, when such a cylindrical permanent magnet magnetic field generator is used, the use efficiency of the generated magnetic field is improved, so that the permanent magnet can be reduced in size.

In each of the embodiments described above, the cross-sectional shape of the through hole 9 formed in the permanent magnet is a cylindrical shape having a constant diameter, but the present invention is not limited to this.

It is a perspective view which shows an example of the stage apparatus which concerns on embodiment of this invention. It is sectional drawing which shows the internal structure of the stage apparatus shown in FIG. 3 is a graph in which the magnetic flux density along the central axis inside the through hole is plotted along the position in the height direction in the ring-type permanent magnet of the stage apparatus shown in FIGS. 1 and 2. 3 is a graph showing a result of calculating the relationship between the magnitude of force received by each bar-type permanent magnet and the position of the bar-type permanent magnet in the stage apparatus shown in FIGS. 1 and 2. In the stage apparatus shown in FIGS. 1 and 2, the magnitude of the force received by the entire bar permanent magnet when the lower end of the bar permanent magnet is arranged at the center of the ring permanent magnet, and the length of the bar permanent magnet It is the graph which showed this relationship. It is a perspective view which shows an example of the stage apparatus which concerns on another embodiment of this invention. It is a perspective view which shows an example of the stage apparatus which concerns on another embodiment of this invention. It is sectional drawing which shows the internal structure of the stage apparatus shown in FIG. It is sectional drawing which shows the internal structure of the stage apparatus shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Table 1a ... Board | substrate mounting surface 2 ... Table base 3 ... Air mover 4 ... Air stator 5 ... Base plate 6 ... Linear motor (drive part)
6a ... Coil 6b ... Permanent magnet for motor 7 (7a, 7b, 7c, 7d) ... Bar-shaped permanent magnet 8 (8a, 8b, 8c, 8d) ... Ring-type permanent magnet 9 ... Through hole 10 ... Tip fixture 11 ... Horizontal bar type permanent magnet 12 ... Horizontal fixture 13 ... Z drive part 13a ... Z coil 13b ... Z permanent magnet 14 ... θ drive part 14a ... θ coil 14b ... θ permanent magnet

Claims (7)

A table for holding the substrate;
A drive unit for moving the table;
A self-weight support device that applies a force of substantially constant magnitude to the table and supports the weight of the table against gravity;
A stage device comprising:
The self-weight support device is
A first permanent magnet which is magnetized in the axial direction and has a column shape having magnetic poles at both ends;
A second permanent magnet having a through hole and magnetized so that a substantially uniform magnetic field parallel to the axial direction of the through hole is generated in a certain range inside the through hole;
One end of the first permanent magnet is inserted in a non-contact manner into the through hole formed in the second permanent magnet, and is disposed so as to be positioned within the range of the substantially uniform magnetic field. ,
The other tip of the first permanent magnet is disposed outside the through hole formed in the second permanent magnet,
A stage device, characterized in that it is a self-weight support device that uses a magnetic force generated between the first permanent magnet and the second permanent magnet as a support force. The stage device according to claim 1, wherein the first permanent magnet is a combination of a plurality of permanent magnets. The stage apparatus according to claim 1, wherein the second permanent magnet is a combination of a plurality of permanent magnets. A table for holding the substrate;
A drive unit for moving the table;
A self-weight support device that applies a force of substantially constant magnitude to the table and supports the weight of the table against gravity;
A stage device comprising:
The self-weight support device is
First, second, and third permanent magnets that are magnetized in the axial direction and have a column shape having magnetic poles at both ends;
The fourth and fifth permanent magnets have a through hole and are magnetized so that a substantially uniform magnetic field parallel to the axial direction of the through hole is generated in a certain range inside the through hole. ,
The first and second permanent magnets are arranged so that they are parallel to each other and their magnetization directions are opposite to each other,
The fourth and fifth permanent magnets are arranged so that substantially uniform magnetic fields generated in the respective through holes are parallel and opposite to each other.
One end of the first permanent magnet is inserted in a non-contact manner into the through hole formed in the fourth permanent magnet, and is disposed so as to be positioned within the range of the substantially uniform magnetic field. ,
The other tip of the first permanent magnet is arranged to be located outside the through hole formed in the fourth permanent magnet,
One end of the second permanent magnet is inserted in a non-contact manner into the through hole formed in the fifth permanent magnet, and is disposed so as to be positioned within the range of the substantially uniform magnetic field. ,
The other end of the second permanent magnet is arranged to be located outside the through hole formed in the fifth permanent magnet,
Among the first permanent magnets, a tip located outside the through hole formed in the fourth permanent magnet;
Of the second permanent magnet, a tip located outside the through hole formed in the fifth permanent magnet,
Connected via the third permanent magnet,
Self-weight that uses the magnetic force generated between the first permanent magnet and the fourth permanent magnet and the magnetic force generated between the second permanent magnet and the fifth permanent magnet as a supporting force. A stage device characterized by being a support device. The stage apparatus according to claim 4, wherein at least one of the fourth and fifth permanent magnets is a combination of a plurality of permanent magnets. 6. The stage apparatus according to claim 4, wherein at least one of the first and second permanent magnets is a combination of a plurality of permanent magnets. The stage device according to any one of claims 4 to 6, wherein the third permanent magnet is a combination of a plurality of permanent magnets.

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