JPH06204321A - Positioning device - Google Patents

Abstract

PURPOSE:To provide a positioning device on which a positioning mechanism having necessary accuracy can be provided in a small space without returning a wafer stage to the original point in a wafer positioning device. CONSTITUTION:The positioning device is provided with spheres 1 to 4, which support a wafer 18 and provided at equal distance from the orthogonally intersecting biaxial intersection, pulleys 5 to 8 which are rotatory driven by motors 9 to 12, and sensors 13 to 16 which are covered by the circumference of the wafer and provided on two axes. Also, a control device, which controls the rotation of the motors 9 to 12 by the position of the wafer 18 detected by the covered part of the sensors 13 to 16 covered by the wafer, is provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wafer positioning device. In the process of manufacturing a semiconductor device, it is necessary to position the semiconductor device at a predetermined position before putting the wafer into the manufacturing device.

As for the positioning, the X-axis and Y-axis positioning for aligning the center of the stage of the apparatus with the center of the wafer and the orientation flat (hereinafter referred to as OF) of the wafer are positioned in a predetermined direction. There is θ axis positioning.

From the above situation, the center of the wafer is made to coincide with the center of the stage of the apparatus, and the O. F. There is a demand for a positioning device capable of positioning the direction of the arrow in a predetermined direction.

[0004]

2. Description of the Related Art A conventional positioning device will be described in detail with reference to FIG. FIG. 7 is a diagram showing a schematic structure of a conventional positioning device.

As shown in FIG. 7, the conventional positioning device has a center of a mounting table of a device for processing the wafer 18 and a wafer.
XY stage 21 for positioning the center of 18 and wafer
18 o. F. The rotation mechanism 22 for positioning the direction of the above in a predetermined direction and the wafer stage 23.

With such a positioning device, the wafer 18
In determining the position of the XY stage 21, first, the XY stage 21 moves in the X-axis and Y-axis directions and the wafer stage 23 located at a position deviated from the center of the XY stage 21 is moved to the center of the XY stage 21. Move 21 to perform home return.

The origin of the XY stage 21 is returned so that the center of the wafer 18 can be positioned at the center of the XY stage 21 even when the position of the wafer 18 mounted on the wafer stage 23 is extremely deviated. , X
This is to secure the amount of movement of the Y stage 21.

Next, the wafer stage returned to the origin
After mounting the wafer 18 on the 23, the XY stage 21 is moved so that the center of the wafer 18 is located at the center of the stage of the apparatus for processing the wafer 18.

In this way, after the center of the wafer 18 and the center of the stage of the apparatus for processing the wafer 18 are aligned with each other, the O. F. The rotation mechanism 22 is rotated so that the direction of is in a predetermined direction.

Since the detection of the origin return of the XY stage 21 is performed in the central portion of the positioning device, the sensor must be provided in the central portion of the positioning device, and the sensor for detecting the position of the wafer 18 is provided in the peripheral portion of the wafer 18. Must be provided.

[0011]

In the conventional positioning device described above, when a new wafer is mounted, the XY stage of the positioning device must be returned to the origin, and the origin return is detected. Since the sensor and the sensor for detecting the position of the wafer have to be separately provided, there is a problem that it is difficult to provide a positioning mechanism with desired accuracy in a small space.

In view of the above situation, the present invention has an object to provide a positioning device which can provide a positioning mechanism with a required accuracy in a small space without returning the wafer stage to the origin.

[0013]

A positioning device of the present invention supports a wafer, and equidistantly from an intersection point of two orthogonal axes, a sphere provided on each of the two axes and a sphere provided respectively on the sphere, and contacting the sphere. A pulley that is driven to rotate by a motor,
A positioning mechanism consisting of a sensor, which is covered by the periphery of this wafer and equidistant from the intersection of two orthogonal axes, and a sensor provided on each of these two axes, was detected by the covered portion of this sensor covered by this wafer. And a control unit for controlling the rotation of the motor according to the position of the wafer.

[0014]

That is, in the present invention, the wafer is supported by spheres provided on the two axes equidistant from the intersection of the two orthogonal axes, the position of the wafer is detected by the sensor, and the motor is controlled by the controller. By rotating the sphere with a pulley fixed to the motor shaft, the wafer is moved linearly in the X-axis or Y-axis direction,
By rotating this sphere in the reverse direction, the wafer is rotated about its center and the O.I. F. Can be matched with a predetermined direction.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to FIGS. 1 is a plan view of a positioning device according to an embodiment of the present invention, FIG. 2 is a sectional view taken along line XX in FIG.
FIG. 3 is a diagram showing the relative positional relationship between the wafer and the sensor before positioning, FIG. 4 is a diagram showing the relative positional relationship between the wafer and the sensor after positioning, and FIG. 5 is a perspective view showing the completed positioning of the wafer. 6 is a connection diagram showing the connection of the control system of the positioning device.

The wafer 18 is mounted equidistantly from the intersection of two orthogonal axes on four spheres 1, 2, 3, 4 respectively provided on the two axes. Actually the sphere 1,2,3,4 by wafer 18
Since it cannot be seen, it should be illustrated by a dotted line, but in FIG. 1, it is illustrated by a solid line as illustrated.

These spheres 1, 2, 3 and 4 are pulleys, respectively.
It is in contact with the perimeter of 5,6,7,8 and is adapted to be rotated by pulleys 5,6,7,8. Motor 9,10,11,12
The rotating shafts 9a, 10a, 11a, 12a of the above are fitted and fixed in the holes of the pulleys 5, 6, 7, 8 respectively.

Sensors 13, 14, 15, 16 capable of detecting the periphery of the wafer 18 are provided on the two axes at equal distances from the intersection of the two orthogonal axes. Since these sensors are composed of a photosensor array of 50 dpi or more, their resolution is about 0.5 mm, and the number of light receiving elements covered by the wafer 18 should be counted by the input selector 17e of the control device described later. You can do it.

FIG. 2 is a sectional view taken along the line X--X in FIG. 1. When the sphere 2 and the sphere 4 are rotated in the directions of the arrows, the wafer is
It is possible to move 18 in the direction of the arrow. In this case, the sphere 1 and the sphere 3 are also rotated in the direction of the arrow by the wafer 18, but as shown in FIG. 1, the sphere 1 and the sphere 3 slip at the contact portion with the pulley 5 and the pulley 7 which are in contact with the sphere 1 and the sphere 3. I am trying.

When the sphere 2 and the sphere 4 are rotated in opposite directions, the wafer 18 can be rotated about the center of the wafer 18. Also in this case, the sphere 1 and the sphere 3 are rotated in the opposite directions by the wafer 18, but slips at the contact portion with the pulley 5 and the pulley 7 which are in contact with the sphere 1 and the sphere 3.

Next, the relationship between the wafer 18 and the sensor will be described. The relationship between the wafer 18 and the sensors 13 and 15 when the center of the wafer 18 is displaced from the center of the positioning device is as shown in FIG. The numbers are different.

In such a case, if the wafer 18 is moved rightward in the drawing as described above, the number of light receiving elements covered by the wafer 18 of the sensor 13 and the sensor 15 is made equal as shown in FIG. Is possible,
Positioning in this direction is completed.

Next, regarding the relationship between the sensor 14 and the sensor 16 and the wafer 18, the same applies to the sensor 14 and the sensor 16.
If the number of light receiving elements covered by the wafer 18 is made equal, the positioning in this direction is completed, and the center of the wafer 18 can be aligned with the center of the positioning device.

FIG. 5 (a) is a perspective view showing the state where the centers are aligned as described above. Wafer 18 at the position of sensor 13
O. F. 5B, the number of light-receiving elements covered by the wafers 18 of the sensors 14, 15 and 16 is the same as shown in FIG. 5B, and the light-receiving elements covered by the wafer 18 of the sensor 13 are the same. The number of elements
The number of light receiving elements other than the number of light receiving elements covered by the wafer 18 is larger than that of the other sensors. F. If the number is reduced by the number corresponding to the height of the arc of 18a, the position of the sensor 13 will be 0.
F. It is possible to position 18a.

This O. F. When it is desired to improve the positioning accuracy of 18a, as shown in FIG. F. If the sensors 13a and 13b are provided within the length of 18a and the number of light receiving elements covered by the wafers 18 of the sensors 13, 13a and 13b is equal, the positioning of the wafer 18 with high accuracy can be achieved. It is possible to

When the sphere is rotated by a motor and a pulley, as shown in FIG.
Input selector 17e
To operate the pulse motor drivers 17a, 17b, 17c, 17d (hereinafter abbreviated as PM driver) using the controller 17, and rotate the motors 9, 10, 11, 12 to position the wafer 18. It is possible to do.

In this way, the relative position between the sensor and the wafer is detected by the sensor, the motor is rotated by the control device, and the sphere is rotated by the pulley, so that the wafer can be positioned. It becomes possible to provide the positioning device in a small space without providing the positioning mechanism.

[0028]

As is apparent from the above description, according to the present invention, the positioning device having an extremely simple structure has an advantage that a positioning mechanism having a required accuracy can be provided in a small space, which is extremely economical. It is possible to provide a positioning device that can be expected to have the effect of improving the reliability and reliability.

[Brief description of drawings]

FIG. 1 is a plan view of a positioning device according to an embodiment of the present invention,

FIG. 2 is a sectional view taken along the line XX in FIG.

FIG. 3 is a diagram showing a relative positional relationship between a wafer and a sensor before positioning,

FIG. 4 is a diagram showing a relative positional relationship between a wafer and a sensor after positioning,

FIG. 5 is a perspective view showing a state in which positioning of the wafer is completed,

FIG. 6 is a connection diagram showing the connection of the control system of the positioning device,

FIG. 7 is a diagram showing a schematic structure of a conventional positioning device,

[Explanation of symbols] 1,2,3,4 are spheres, 5,6,7,8 are pulleys, 9,10,11,12 are motors, 9a, 10a, 11a, 12a are rotating shafts, 13,13a, 13b, 14,15,1
6 is a sensor, 17 is a controller, 17a, 17b, 17c, 17d are PM
Driver, 17e is input selector, 18 is wafer,

Claims (2)

[Claims] 1. A sphere (1, 2, 3,) which supports a wafer (18) and is equidistant from the intersection of two orthogonal axes and is provided on each of the two axes.
4) and the sphere (1,2,3,4) respectively, and the motor (9,10,1
The pulleys (5,6,7,8) that are driven to rotate by 1,12) and the circumference of the wafer (18) are provided on the two axes equidistant from the intersection of the two axes that intersect at right angles. Sensor (1
3,14,15,16) and the sensor (13,1) covered by the wafer (18).
4,15,16) wafers (1
A positioning device comprising: a control device (17) for controlling the rotation of the motors (9, 10, 11, 12) according to the position of 8). 2. The positioning device according to claim 1, wherein sensors (13a, 13a) are provided on both sides of the sensor (13) for detecting a position of an orientation flat of the wafer (18).
A positioning device comprising b).