JPH0534109Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a chuck device, and particularly to a chuck device having a rotation mechanism.

[Prior Art] Conventionally, this type of chuck device has a third and a fourth
As shown in the figure, there is a chuck support 2 with a circular recess in the center, a circular chuck 1 that is loosely inserted into the recess of the chuck support 2, and placed on the bottom of the chuck support 2, and a chuck that can be inserted from the outside. A DC motor 4 is provided to rotate the chuck by penetrating the bottom of the recess of the support base 2, and a ball bearing 3 is installed in the gap between the side wall of the recess of the chuck support base 2 and the outer peripheral surface of the circular chuck 1. Alternatively, the rotation of the chuck 1 can be adjusted by providing a roll bearing 5 between the bottom of the recess of the chuck support 2 and the lower surface of the chuck 1.

However, when using ball bearings and roll bearings, there is a problem of dust generation due to the frictional drive of the bearings.

For this reason, in recent years, air bearings have been used instead of ball and roll bearings.

[Problems to be Solved by the Invention] However, the above-mentioned air bearing has the disadvantage that, because of its low rigidity, it is likely to vibrate when the chuck device moves, and it takes time to come to rest.

In view of the above drawbacks, the technical problem of the present invention relates to a chuck device that does not generate dust and has a highly rigid rotation mechanism.

[Means for solving the problem] According to the present invention, first and second
A chuck having a cylindrical chuck member having an end face and fixing a wafer on the first end face, and a chuck supporting member rotatably supporting the chuck member on which the second face is placed and received. In the apparatus, an ultrasonic motor having a vibrating body and a movable body rotated by the vibration of the vibrating body is provided between the second surface and the chuck support member, and the ultrasonic motor is provided between the second surface and the chuck support member, and the second surface is mounted on the movable body. are in surface contact with each other to rotatably support the chuck member, and on the other hand, an air piping section for vacuum suction that faces the movable body and opens on the second surface,
A chuck device characterized in that it is provided on the chuck member is obtained.

Further, according to the present invention, the chuck supporting member is provided with a side wall portion that surrounds the outer circumferential surface of the columnar chuck member at a distance, and the gap between the side wall portion and the outer circumferential portion is filled with a magnetic fluid. A chuck device is obtained which is characterized in that it is sealed.

Note that it is preferable that the second surface is provided with an electromagnetic member.

[Example] Next, an example of the present invention will be described with reference to the drawings.

As shown in FIG. 1, 1 is a cylindrical chuck on which a wafer is mounted. Reference numeral 2 denotes a chuck support base, which is provided with a recess into which the chuck 1 is loosely inserted. At the bottom of the recess, an ultrasonic motor 6 consisting of a vibrating body and a movable body rotated by the vibration of the vibrating body is installed, and is arranged so that the movable body and the lower surface of the chuck 1 are in surface contact with each other. has been done. Further, the gap between the side wall of the recess and the outer periphery of the chuck 1 is sealed using a magnetic fluid 10 in order to prevent dust from dispersing to the outside. Permanent magnets 9 are provided on the side walls of the recess and the outer periphery of the chuck 1, thereby holding the magnetic fluid 10.

As shown in FIGS. 2a and 2b, the bottom surface of the chuck 1 is provided with the
An air piping section 8 for vacuum suction that opens on the bottom surface of the
They are arranged concentrically and connected to an externally provided vacuum pump (not shown), thereby forming a vacuum mechanism. Using such a vacuum mechanism,
By degassing, the chuck 1 and the chuck support base 2 are vacuum-adsorbed via the ultrasonic motor 6. Also, in parallel with the air piping section 8, an electromagnet group 7
is provided on the bottom surface of the chuck 1.

As a result, the rotation adjustment can be performed with the bottom surface of the chuck 1 in surface contact with the ultrasonic motor 6, so that after the rotation adjustment, electromagnetic force or vacuum suction through the air piping section 8 can be applied. Therefore, even if the chuck 1 and the chuck support base 2 are suctioned and fixed, the rotation adjustment will not be erroneously adjusted. Therefore, it is possible to integrate the chuck 1 and the chuck support base 2 by vacuum suction and electromagnetic force, and to achieve high rigidity that prevents errors in rotation adjustment even when the chuck device is moved. Note that when the chuck device is used vertically, by using the electromagnetic force of the electromagnet group 7, it is possible to effectively prevent the chuck 1 from deviating during rotation adjustment.

Next, a specific procedure for rotation adjustment will be explained.

First, the electromagnet 7 is energized, and while the chuck 1 and the chuck support base 2 are held together by the electromagnetic force so as not to be separated, the ultrasonic motor 6 is driven to perform rotation adjustment.

After the rotation is completed, the vacuum mechanism is operated, and the chuck 1 and the chuck support base 2 are fixed with high rigidity by the cooperation of the vacuum suction force and the electromagnetic force.

Finally, move the chuck device.

In addition, in such work, dust generated by the frictional drive of the ultrasonic motor is shielded by the magnetic fluid, and therefore does not spread to the outside.

[Effects of the invention] As explained above, according to the invention, the moving body of the ultrasonic motor provided on the chuck support base is brought into surface contact with the lower surface of the chuck, and air for vacuum suction is provided on the lower surface of the chuck. Since the piping section is opened or an electromagnet is provided, the chuck and the chuck support base can be fixed together with high rigidity. In addition, since a side wall surrounding the chuck's outer circumferential surface is provided on the chuck support base, and the gap between the side wall and the chuck's outer circumferential surface is sealed with magnetic fluid, dust generated by the frictional drive of the ultrasonic motor is prevented from going outside. Divergence can be prevented.

[Brief explanation of the drawing]

FIG. 1 is a schematic sectional view showing an embodiment of the present invention;
2a and 2b are a bottom view and a schematic sectional view of the chuck shown in FIG. 1, and FIGS. 3 and 4 are schematic sectional views of the conventional chuck device. 1...chuck, 2...chuck support base, 6...
...Ultrasonic motor, 7...Electromagnet, 8...Air piping, 9...Permanent magnet, 10...Magnetic fluid.

Claims (1)

[Claims for Utility Model Registration] 1. Having first and second end surfaces facing each other,
A chuck device having a cylindrical chuck member for fixing a wafer on the first end surface, and a chuck support member for resting and receiving the second surface and rotatably supporting the chuck member, comprising: a vibrating body; an ultrasonic motor having a movable body that rotates due to vibrations of the vibrating body is provided between the second surface and the chuck support member, and the second surface is in surface contact with the movable body, What is claimed is: 1. A chuck device, characterized in that the chuck member is rotatably supported, and the chuck member is provided with an air piping portion for vacuum suction that faces the movable body and opens on the second surface. 2. The chuck device according to claim 1, wherein the chuck supporting member is provided with a side wall portion that surrounds the outer peripheral surface of the columnar chuck member at a distance, and a gap between the side wall portion and the outer peripheral portion is provided. A chuck device characterized by being sealed with magnetic fluid. 3. A chuck device according to any one of claims 1 and 2, characterized in that the second surface is provided with an electromagnetic member.