JPS6378092A - Rotary table - Google Patents

Abstract

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

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a stage that rotates in θ, and is particularly used as a stage for semiconductor inspection equipment, processing equipment, and exposure equipment.

[Conventional technology]

Conventionally, this type of rotary table was manufactured by Utility Model Publication No. 56-4794.
As described in publications such as No. 8 or Japanese Patent Application Laid-Open No. 60-185729, the rotation of the motor is transmitted to a feed screw and one end of the rotary table is moved via a nut as a means for rotating a one-turn table. I used the same method. Also, for minute rotation, the voltage of the piezoelectric element is controlled at one end of the one-turn table. It was trembling slightly. Such means requires elemental parts necessary for driving the one-turn table, such as a motor, a feed screw, a nut, a bearing, etc., resulting in a large-sized rotary table system. These rotary tables are usually equipped with a moving table (x
y stage, etc.) and is used to align the running direction of the moving table and the inclination of the pattern of the wafer, mask, etc.
When the rotary table becomes larger, the moving table also becomes larger and the inertial load during movement increases, resulting in problems such as high-speed movement and longer time required for positioning. Additionally, positioning errors may occur due to the influence of heat generated by the motor.

For minute positioning, it is necessary to use a piezoelectric element in addition to the driving source described above, and the structure may become complicated and expensive.

[Problem that the invention seeks to solve]

The above-mentioned conventional technology does not give consideration to making the rotary table including the drive system small, lightweight, and simple in structure, resulting in a large single rotary table.

There was a problem with the complicated mechanism.

An object of the present invention is to make a single-turn table small and lightweight, and to achieve high rotation accuracy with a simple mechanism.

In addition, by having the function of holding wafers, masks, etc. on the rotary table, one of the objectives is to eliminate the need for chucks for wafers and masks, which were previously required, and to make the entire moving stage system lightweight and simple. It is.

[Means for solving problems]

The above purpose is to hold a rotatable table on a moving platform,
This is achieved by rotating the rotary table by bringing a member held by an object that is fixed relative to the movable base into contact with a part of the rotary table while moving the movable base.

Also, by adding a mechanism to attract or hold wafers and masks on one surface of the rotary table.

It is also possible to eliminate the need for a chuck.

[Function] The rotary table performs one rotation by moving the moving table and contacting the end face of the rotary table.

When a piezoelectric element, an electromagnet, a fluid action, etc. are used as a contact action means, it is necessary to perform a rotation action of a one-turn table. Elemental parts such as motors, feed screws, and nuts are no longer required on the movable table, resulting in a small, light, and simple rotary table. The rotational resolution of this rotary table can be made high by minimizing the amount of movement of the moving table, and one rotation stroke is small.

It can be arbitrarily varied by lengthening the stroke of the moving table. This eliminates the need for a dedicated drive system for fine rotation, and provides long stroke and high-resolution rotational performance. In addition, if the rotary table itself can attract or hold wafers and masks, there will be no need to chuck wafers or masks.
A stage system using this table has the advantage of being simple in structure, lightweight, and inexpensive.

〔Example〕

Embodiments of the present invention will be described below with reference to FIGS. 1 and 2. FIG. 2 is a sectional view taken along the line AA in FIG. 1. base 1
The X stage 2 provided above can be moved in the direction of arrow BB' by a motor 3 and screws 4.

A θ stage 5 is guided by a rotation pin 6 on the X stage 2 . A holding part α21 for vacuum suctioning the θ stage 5 is formed on the X-mount 2, and a holding part A5+ for vacuum suctioning the wafer 7 is formed on the θ stage, each of which is connected to a vacuum source (not shown). A piezoelectric element 9 is fixed to a holder 8 fixed to the base 1, and the other end of the piezoelectric element has one end fixed to the base 1 and a θ stage 5.
It is fixed to a contact plate 10 arranged so as to be in contact with the side surface of. When a voltage is applied to the piezoelectric element 9, the piezoelectric element 9
is deformed, and the contact plate 10 comes into contact with the side surface 52 of the θ stage 5, and when no voltage is applied, the contact plate 10 and the side surface 52 of the θ stage 5 are in contact. This embodiment consists of the above-mentioned devices, and when rotating the θ stage 5, a voltage is applied to the piezoelectric element 9, and the vacuum in the holding part a21 is opened to the atmosphere.

Next, when the motor 5 is driven to move the X stage 2 in the B direction, the side surface 52 of the θ stage 5 is in contact with the contact plate 10, so a tangential force acts on the outer periphery of the θ stage 5, and the five The rotation pin serves as a rotation guide, and the θ stage 5
rotates in the C direction. In the above method, as an example, if the diameter of the θ stage 5 is 200 mm, the rotation angle stroke 5
In order to obtain the desired accuracy, the feed amount of the X-stage 2 should be within 2 seconds, and the feed resolution of the X-stage should be within 1 μm. If the above method is used, it is quite possible to obtain a resolution of 2 seconds. If you want to invert, do the same and press
When the moving direction of the stage 2 is set in the B' direction, the θ stage 5 rotates in the C' force direction. If the contact plate 10 has a structure that can be elastically deformed (for example, a plate spring), the θ stage 5 will rotate somewhat eccentrically with respect to the guide 6, and the contact position between the contact plate 10 and the side surface 52 of the θ stage 5 will change. Since the side surface 52 is pressed with a constant force even when rotating, the side surface 52 will not be deformed due to excessive pressure during rotation and the rotation accuracy will not deteriorate. After completing the rotation adjustment.

Since the rotary stage 5 is structured to be fixed by vacuum suction, no force in the rotational direction is applied during fixation, and high resolution can be maintained. Furthermore, if the piezoelectric element 9 is used as a moving actuator for the contact plate 10, a high-speed response is possible, and even if the moving speed of the x, x, 7-ji 2 is high, a minute rotation can be obtained. A third actuator for movement of the contact plate 10
As shown in the figure.

The electromagnet 12 may be fixed to the fixed plate 11. In the case of the piezoelectric element 9, this is a small stroke number of about 10 to τ00 μm, so it is also necessary to provide an enlargement mechanism.

For this reason, using the electromagnet 12 is also an effective means.

If the side surface of the θ stage 5 cannot be contacted, the upper surface of the θ stage 5 may be contacted as shown in FIGS. 4 and 5. In this case, a lever 13 for contact is provided, one end of the lever is driven by an actuator such as the piezoelectric element 9 (or electromagnet 12), the other end is brought into contact with the top surface of the θ stage 5, and the lever is operated in the same manner as described above. That's fine. By making the contact plate 10 and the lever 13 contacting the θ stage 5 equal to the stroke of the X stage 20, the rotation can be matched no matter where the X stage 2 is located.

The θ stage 5 has a holding portion b that attracts the wafer 7.
51, it can also be used as a wafer chuck, which has the advantage of eliminating the need for a dedicated wafer chuck.

〔Effect of the invention〕

As explained above, according to the present invention, element parts necessary for driving the rotary table, such as a motor, a feed screw, a nut, a bearing, etc., are not required, and the rotary table has a small size and simple configuration. Therefore, the movable table on which the rotary table is placed is also small and lightweight, the penetrating load on the movable table is reduced, and the time required for high-speed movement and positioning is shortened.

Furthermore, since the rotary table can be used as a chuck for wafers and masks, a dedicated chuck is not required.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing the configuration of an embodiment of the rotary table of the present invention, FIG. 2 is a sectional view taken along the line A-A in FIG.
4 is a sectional view of an embodiment of the present invention, FIG. 4 is a configuration diagram of an embodiment to which the present invention is applied, and FIG. 5 is a sectional view taken along the line D--D in FIG. 4. 2・・・・・・・・・・・・X stage. 5・・・・・・・・・・・・θ stage. 6・・・・・・・・・・・・Rotating bottle. 9...Piezoelectric element. 10・・・・・・・・・Contact plate. 21......Holding part α. 51......Holding section. 52・・・・・・・・・Side. Agent Patent Attorney Katsutoshi Ogawa'- Figure 1 Figure 2 2 Contact plate 6 times @ bottle

Claims (1)

[Claims] 1. A rotary table that is installed on a movable base and is rotated by the movement of the movable base and by means of contacting the rotary table from a member other than the movable base.