JPH01303044A - Linear motor driving mechanism by means of superconducting coil - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Summary] The present invention relates to a linear motor drive mechanism using a linear motor, particularly a linear motor drive mechanism useful for precision movement stages used in positioning wafers etc. with high precision in semiconductor manufacturing equipment. The purpose of the present invention is to provide a linear motor drive mechanism that uses a superconducting coil element instead of a permanent magnet element to bring a driving force acting point and a guiding engagement point closer to each other, and includes a guide rod member made of a magnetic material and a guide rod member made of a magnetic material. , comprising a movable member slidably attached to the guide rod member, and a plurality of superconducting coil elements provided along the guide rod member at predetermined intervals, the superconducting coil element being a guide loft member. They are arranged so as to generate magnetic flux on opposing surfaces, and are energized so that the magnetic flux becomes a reversed flux along the axis of the guiding rotor.
and a conductor coil element incorporated in a movable member, and the conductor coil element is arranged so as to constitute a linear motor together with the superconducting coil element.

[Industrial application field]

The present invention relates to a linear motor drive mechanism using a linear motor, and more particularly to a linear motor drive mechanism useful for precision movement stages used in positioning wafers and the like with high precision in semiconductor manufacturing equipment.

[Prior Art] As an example of a linear motor drive mechanism that utilizes a linear motor, one that is incorporated into a wafer movement stage used in the semiconductor manufacturing field is known. Such a wafer movement stage is used to position the wafer at a predetermined exposure position when exposing a mask pattern to a POI resist layer on the wafer. This type of wafer movement stage is equipped with a wafer holding carrier that can be positioned at any position on the xy plane, and the wafer holding carrier is moved in the X and Y directions on the XY plane to a predetermined position. It will be positioned at the exposure position.

Referring to FIG. 3, an example of such a wafer movement stage is shown, which wafer movement stage comprises a wafer holding carrier 1. In order to be able to move the wafer holding carrier 1 in the X and Y directions respectively in XY planes, a first support loft member 2 and a second support rod part 3 are attached to the wafer holding carrier. They are slidably inserted into A-1 so as to be perpendicular to each other. A pair of first guide rail members 4 are laid on both end sides of the first support loft member 2, and the pair of first guide rail members 4 extend parallel to the second support loft member 3. be made to exist. Guide engaging stands are provided on both end sides of the first support rod member 2, and the guide engagements on both end sides are slidably maintained with corresponding ones of the pair of first guide rail members 4. and thereby the first support loft member 3
becomes movable along the pair of first guide rail members 4. Similarly, a pair of second guide rail members 5 are laid at both ends of the second support loft member 3, and the pair of second guide rail members 5 are connected to the first support loft member 2. Extended in parallel. Furthermore, guide engaging stands are provided on both end sides of the second support loft member 3, and the guide engagements on both end sides are slidable with corresponding ones of the pair of second guide rail members 5. Similarly, the second supporting rail member 3 can be moved along the pair of second guide rail members 5.

In short, the wafer holding carrier 1 slidably receives both support rod members at orthogonal positions to the first support loft member 2 and the second support loft member 3. When the wafer holding carrier A-1 is moved on the pair of first guide rail members 4, the wafer holding carrier A-1 moves along the second support loft member 3 (in the X direction on the XY plane in FIG. 3).
When the second loft member 3 is moved on the pair of second guide rail members 5, the wafer holding carrier 1 moves along the first loft member 2 (in the Y direction). The wafer holding carrier 1 is moved by x
It is positioned at an arbitrary position on the y-plane, for example, at a predetermined exposure position.

As suggested in the foregoing description, a first support loft member 2 and a second support loft member 3 are provided on the pair of first guide rail portion sides 4 and the pair of second guide rail members 5, respectively. If a linear motor is used for driving along the line, such a linear motor may be installed at both ends of the first side 1 and the bottom side 2 and the second mouth/bottom side 3. It happens every time I get it. Since the configurations of these linear motors are substantially the same, only the linear motor provided at one end of the first Ron 1 member 2 will be explained.

As shown in FIG. 4, the linear motor includes a conductor coil element 6 supported at one end of the first loft member 2, and a pair of first guide rail members 4 inserted through the conductor coil element 6. The core member 7 is made of a suitable magnetic material such as iron and extends parallel to the core member 7, and a plurality of permanent magnet elements 8 are disposed adjacent to the core member 7 along one or both sides of the core member 7. Ru. Similar to the configuration of known linear motors, a portion of the conductive coil element 6 can pass between the core member 7 and a plurality of permanent magnet elements 8 disposed along one or both sides thereof. The plurality of permanent magnet elements are arranged so as to alternately have different polarities on opposing surfaces facing the core member. Needless to say,
In the linear motor configured as described above, by appropriately switching the direction of energization to the conductor coil element 6, the conductor coil element 6 receives a driving force in the direction along the central axis of the core member 7, and thereby the first support The rod member 2 will be moved along the pair of first guide rail members 4.

[Problem to be solved by the invention]

Now, in the above-mentioned linear motor drive mechanism, for example, when the first support rod member is moved on a pair of guide rail members that are slidably engaged with the guide retaining portion thereof, the driving force is applied to the guide rail member. The problem is that it acts on a location away from the engagement, that is, on the conductor coil element. That is, while the driving force acts on the conductor coil elements attached to the extreme ends of the pair of rod support members, the part that receives the driving force and moves is the guide support inside the conductor coil element. The problem is that it is a joint.

This is because the conductor coil element on which the driving force acts and the retaining guide part that moves in response to the driving force are separated, so when the conductor coil element is driven with sudden acceleration, the guide engagement part This is because the rapid movement of the conductor coil element may involve rotational movement such as yawing. Specifically, since the same driving force is applied to the two conductor coil elements at both ends of the first support rod member, the wafer holding carrier is placed at the center of the first support rod member. When the two conductor coil elements are driven, the loads applied to them are the same, so that when the two conductor coil elements are driven, the two inner guide joints are compared. Since the conductor coil elements can be moved with good followability, it is possible to drive the conductor coil elements with relatively large accelerations. However, on the other hand, when the wafer holding carrier is biased towards one end of the first support rod member, the conductor coil element on the side closer to the wafer holding carrier A. The applied load is larger than that of the conductor coil element on the opposite side, so when the side conductor coil element is driven with a sudden acceleration, the movement of the former conductor coil element will lag behind the movement of the latter conductor coil element. As a result, yawing will occur during movement of the first support rod member.

Therefore, in the conventional linear motor drive mechanism incorporated in the wafer movement stage as described above,
Since the conductor coil element on which the driving force acts and the retaining guide part that moves in response to the driving force are separated, the movement speed of the first support loft member is limited, and this reduces semiconductor manufacturing costs. This is considered to be one of the hindering factors.

In the above description, the problems of the conventional linear motor drive mechanism have been described in relation to the wafer movement stage, but there are also problems with the linear motor drive mechanism itself, such as the location where the driving force acts and the location where the driving force is received. It has been pointed out that the moving parts are separated. For example, a linear motor having the above-described configuration is incorporated into a guide engagement member that is slidably engaged with a single guide rod portion, and the guide stand member is moved along the single guide rod member. In this case, problems with followability of the guide engagement member may occur.

This is because the driving force acts on a location away from the guide engagement member, so a rotational action acts on the guide engagement member. This is because the member may not be able to follow it.

In short, the causes of the various problems associated with the conventional linear motor drive mechanism and various devices incorporating it, such as wafer movement stages, as described above, are the locations where the driving force acts and how the drive force moves in response to the driving force. This comes down to the fact that it is separated from the guide station. The only way to solve this problem is to incorporate a thin conductor coil element in the guide engagement point to match the driving force application point and the guide engagement point, but permanent magnets are used as one of the components of the linear motor. Conventional linear motor drive mechanisms using elements do not solve the problem. This is because in order to obtain a large driving force, a large magnetic flux density is required, and for this purpose it is necessary to place the iron core member, conductive coil element, and permanent magnet element very close together, or in fact In this case, a hair ring mechanism or the like is incorporated in the guide engagement portion to achieve low friction engagement with the guide rod member, and for this reason, it is impossible to arrange the conductor coil element and the permanent magnet element close to each other. It is. On the other hand, by using a large and powerful permanent magnet element and a corresponding conductor coil element, a large driving force can be obtained even when the permanent magnet element and the conductor coil element are relatively separated, but in this case, the linear motor Not only would the weight of the drive mechanism be enormous, but also its power consumption would be considerable, making such a solution impractical.

Accordingly, an object of the present invention is to provide a linear motor drive mechanism that uses superconducting coil elements in place of permanent magnet elements so that the driving force application area and the guiding engagement area can be brought closer to each other.

[Means to solve problems]

The linear motor drive mechanism according to the present invention includes a guide port Y1 member made of magnetic API, and a guide rod portion +4 which is guided and moved along the axial direction of the guide rod member +4. and a plurality of superconducting coil elements installed along the axis of the guide rod part H at predetermined intervals from the guide rod part (A). The coil element is guided 1
11 It is arranged so as to generate magnetic flux on the opposite surface side facing the nodobe shrine, and the magnetic flux is a part of the guide day 1]
Electricity is applied so that the bundle is reversed along the axis of A. The linear motor drive mechanism according to the present invention further includes a conductor coil element incorporated in the movable part +J, and this conductor coil element is arranged so as to constitute a linear motor together with a plurality of superconducting coil elements.

[For production]

As is clear from the above configuration, in the linear motor drive mechanism according to the present invention, one of the components of the linear motor is
As a superconducting coil element that is relatively lightweight and can generate a very large magnetic field, it is necessary to incorporate the conductor coil element into the movable part restraint, that is, the guide engagement part, which is slidably attached to the guide rod member. becomes possible.

〔Example〕

Next, an embodiment of the linear motor drive mechanism according to the present invention will be described with reference to FIG. 1, and with reference to FIG. 2, when the linear motor drive mechanism according to the present invention is applied to a wafer movement stage. An application example will be explained.

FIG. 1 shows a perspective view of a linear motor drive mechanism constructed in accordance with the present invention, which includes a guide rod member 1 made of a magnetic material, for example pure iron.
0, and a movable part +J] 2 that is slidably attached to the guide rod member 10 so as to be guided and moved along the axial direction of the guide rod member 10.

As shown, in this embodiment the guide rod member 10 has a rectangular cross-section and is secured to a pair of suitable support block members 14 disposed on the underside of each end thereof.

Further, the movable member 12 has a cubic shape, and a through hole with a rectangular cross section is formed in the side of the movable member 12 so that the guide solar 1 member 10 can be slidably inserted therethrough.

An air hair ring is formed between the movable member 12 and the support rod member 10 to provide low friction sliding therebetween. That is, a large number of small air jetting holes (not shown) are formed in the four inner wall surfaces of the through hole having a rectangular cross section formed in the movable member 12, and these small air jetting holes are formed in the movable member 12. air passage (
A movable air supply pipe (not shown) is connected to the air passage.

In short, by supplying compressed air to the air passage through the air supply pipe and ejecting it from the air jet small hole,
An air layer is formed between the four inner walls (]4) of the through hole of the movable member 12 and the retaining surface of the support loft side 10, and this acts as an air hair ring. Although an air hair ring was used in this example,
It goes without saying that other bearings can be used, such as roller hair rings.

Further, a conductor coil element 16 is incorporated in the movable member 12, and this conductor coil element is formed by winding a copper wire into a coil in a rectangular shape.
embedded in the manner shown in the figure.

As shown in FIG. 1, side yoke members 18 are provided along the guide rod member 10, and the side yoke members 18 are spaced parallel to the central axis of the guide rod member 10 and at predetermined intervals. be done. On one side of the side yoke member 18, that is, on the side facing the guide rod member 10, a superconducting coil element 2 made of a superconducting material is provided.
0a to 20d are arranged along the central axis of the guide rod member 10. These superconducting coil elements 20a to 20d, the conductor coil element 16, and the guide rod member 10
and constitute a linear motor. However, as is clear from FIG. 1, the superconducting coil element 20
The superconducting coil elements 20a to 20d are arranged so as to generate magnetic flux on the side facing the guide rod member 10, and the superconducting coil elements 20a to 20d are energized so that the magnetic flux generated by them is aligned along the axis of the guide rod part side 10. It is done so that it is reversed. In short, the guide rod member 1
On the 0 side, the superconducting coil element 20a has the N pole, the superconducting coil element 20b has the S pole, and the superconducting coil element 20c has the N pole.
The superconducting coil element 20d generates a north pole, and the superconducting coil element 20d generates a south pole.

At this time, a magnetic field as shown by arrow 22 is generated in superconducting coil elements 20a and 20b, and a similar magnetic field is also generated in superconducting coil elements 20C and 20d.

Next, the operation of the above-mentioned linear motor drive mechanism will be explained.

The movable member 12 is a superconducting coil element 2 as shown in FIG.
When the conductor coil element 16 is energized while facing 0b, the movable member 12 moves in the direction of the arrow 24a or 24 depending on the direction of energization, according to Fleming's left hand rule.
The driving force will be applied in either direction b. For example, when the conductor coil element 16 is energized so that a current flows downward through the copper wire portion group on one side of the conductor coil element 16, that is, the side facing the superconducting coil element 20b, the movable member 12 moves toward the arrow 24b. When the movable member 12 receives a driving force in the direction of arrow 24b and moves toward the superconducting coil element 2OC side, and the direction of energization to the conductor coil element 16 is reversed at the point where the magnetic flux is reversed, the movable member 12 continues to receive a driving force in the direction of arrow 24b. The superconducting coil element 20d receives the superconducting coil element 20d. By sequentially switching the current direction in this way, the movable member 12
is continuously driven in the direction of arrow 24b.

On the other hand, if the initial energization direction is reversed, the movable member 12 is driven in the direction of the arrow 24a, and by sequentially reversing the energization direction, the movable member 12 is continuously driven in the direction of the arrow 24a. become.

In the above-mentioned operation example, the movable member 12 was driven in the direction of the arrow 24a or 24b by switching the amount of power applied to the conductor coil element 16, but the direction of the current applied to the conductor coil element 16 was always changed to constant. It will be obvious that the current direction to the superconducting coil elements 20a to 20d may be switched at the same time.

In the embodiment shown in FIG. 1, the movable member 12 can function as a wafer carrier base, and various articles such as workpieces, tools, or print heads can be mounted thereon. be. In short, a predetermined article is mounted on the movable member 12 depending on the linear motor drive mechanism shown in FIG. 1 or the equipment used.

Referring to FIG. 2, there is shown a wafer movement stage utilizing a linear motor drive mechanism as described above. A pair of guide rod members 26 are disposed in parallel to each other on this wafer moving stage, and each guide rod member 26 is arranged in parallel with each other.
6 is secured on a pair of suitable support block members 28 in a manner similar to the guide rod members 10 described above. Movable member 2
0 is in the form of a rectangular parallelepiped with a medium wide shape, and a pair of guide loft members 26 are slidably inserted into both sides of the rectangular parallelepiped. To provide low friction movement of the movable member 30 relative to the pair of guide rod members 26, air bearings as described above may be provided, or roller hair rings may be provided.

Conductor coil elements as shown in FIG. 1 are incorporated into each of the opposite end portions of the movable member 30, and side yoke members 32 are disposed along each of the outer side surfaces of the pair of guide rod members 26. A plurality of superconducting coil elements 34 having the same configuration as the superconducting coil elements described above are arranged in the superconducting coil element 34 . Therefore, the conductor coil elements incorporated at each end of the movable member 30 together with the corresponding arrangement of the plurality of superconducting coil elements 34 constitute a linear motor.

As shown in FIG. 2, an elongated support plate member 36 is provided on the second surface of the movable member 30, and the longitudinal axis of this support plate portion tA'36 is the center axis of the pair of guide rod members 26. It is arranged in such a manner that it is perpendicular to. The support plate element 36'2 is provided with a single guide rod member 38, which single guide rod member 38 is similar to the above-mentioned guide rod member 38'.
A pair of suitable support flock members 4 in a similar manner to A10.
Fixed on 0. The movable member 42 is constructed as in FIG. 1 and has a single guide rod member 38 slidably inserted therein and a conductor coil element as in FIG. 3 incorporated therein. . In the case of FIG. 3, movable member 42 functions as a wafer holding carrier.

A plurality of superconducting coil elements 44 having a configuration similar to that shown in FIG. Configure.

With such a configuration, the movable member, that is, the wafer holding carrier 42, can be moved in both the X direction and the Y direction on the XY plane by operating the above-mentioned linear motor. Wafer holding carrier 4
2 can be properly positioned at a predetermined exposure position.

[Effects of the Invention] As is clear from the above description, the linear motor drive mechanism according to the present embodiment uses a plurality of lightweight superconducting coil elements that can generate a strong magnetic field. It becomes possible to incorporate the conductor coil elements constituting the motor into a movable member that can move along the guide rod member, and as a result, the movable member and the driving force generation point can be brought close to each other. Even if the movable member is driven with a sudden acceleration, yawing can be small. Therefore, the working efficiency of the equipment using the linear motor drive mechanism according to this embodiment is improved.

[Brief explanation of the drawing]

FIG. 1 is a schematic perspective view showing an embodiment of a linear motor drive mechanism according to the present invention, and FIG. 2 is a schematic perspective view of a wafer movement stage to which the linear motor drive mechanism according to the present invention is applied.
FIG. 3 is a schematic perspective view of a wafer movement stage to which a conventional linear motor drive mechanism is applied, and FIG. 4 is a perspective view showing details of the linear motor drive mechanism of the wafer movement stage shown in FIG. 10... Guide Rondo part shrine, 12... Movable member,
16... Conductor coil element, 202-20d... Superconducting coil element.

Claims (1)

[Claims] 1. A guide rod member made of a magnetic material, a movable member slidably attached to the guide rod member so as to be guided and moved along the axial direction of the guide rod member, and the guide rod. a plurality of superconducting coil elements provided along the axis of the guide rod member at predetermined intervals from the member, and these superconducting coil elements are arranged so as to generate magnetic flux on the opposing surface side facing the guide rod member. energized so that the magnetic fluxes are reversed along the axis of the guide rod member, and
A linear motor drive mechanism comprising: a conductor coil element incorporated in the movable member, the conductor coil element being arranged so as to constitute a linear motor together with the plurality of superconducting coil elements.