JP2000277588A - Rotary stage - Google Patents

Abstract

(57) [Problem] To provide a rotary stage capable of maintaining the direction of a wafer in a fixed direction. SOLUTION: A rotatable rotary stage (first type) is provided.
Rotating stage 5), a plurality of wafer stages 13 (second rotating stage) which are rotatably provided at positions eccentric from the rotation axis of the rotating stage 5 and on which the wafer 11 is mounted, and the rotation of the rotating stage 5 A transmission means T for transmitting the rotation of the rotation stage 5 in the direction opposite to the rotation direction of the rotation stage 5 to the rotation shaft 15 of the wafer stage 13 while keeping the rotation amount of the shaft 7 as it is.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary stage provided on an exposure apparatus such as an inspection apparatus or a stepper and on which a wafer is mounted.

[0002]

2. Description of the Related Art When a large number of wafers are to be processed in a short time in an inspection apparatus or an exposure apparatus, there are a continuous type in which the processing is continuously performed like a flow operation, and a batch type in which a large number of wafers are processed at a time. There is.

In the case of a continuous type, a continuous traveling stage is used as a stage on which a wafer is mounted. on the other hand,
In the case of the batch type, a rotating stage is used in which a large number of wafers are placed and rotated to move a desired wafer to a predetermined position.

[0004]

However, since the continuous traveling stage performs inspection and exposure while the wafer is moving, it is difficult to perform advanced inspection and exposure.

In addition, when inspecting and exposing at high speed,
Intense reciprocating motion of the stage is required, and vibration and the like become a problem, and accuracy is reduced. On the other hand, with a rotary stage, high-speed inspection is possible by rotating the rotary stage, but since the direction of the wafer changes, it is difficult to correct defect coordinates due to poor alignment by parallel movement or the like.

Further, Die To Die (die-to-die) comparison is not easy because high-speed coordinate conversion is required. For this reason, it is difficult to detect a defect on a patterned wafer. The present invention has been made in view of the above problems, and its purpose is to:
It is an object of the present invention to provide a rotary stage that can keep the direction of a wafer constant.

[0007]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a first rotatable table rotatably provided, and a rotatably provided rotatable position eccentric from a rotation axis of the first rotatable table. ,
A plurality of second turntables on which wafers are mounted, the rotation amount of the rotation shaft of the first turntable as it is, and rotation of the first turntable in a direction opposite to the rotation direction of the second turntable is the second turntable. And a transmission means for transmitting power to the rotation shaft of the turntable.

A transmission means for transmitting the rotation amount of the rotation shaft of the first turntable as it is and transmitting the rotation in the direction opposite to the rotation direction of the first turntable to the rotation shaft of the second turntable. With this arrangement, the direction of the second turntable is maintained in a constant direction even when the first turntable rotates.

Therefore, the direction of the wafer can be kept constant. Here, as an example of the transmission means, as described in claim 2, a first pulley provided on a rotation shaft of the first turntable and a first pulley provided on a rotation shaft of the second turntable are provided. There is a transmission means including a second pulley having the same diameter as the diameter of the first pulley, and a belt wound around the first pulley and the second pulley.

In order to perform accurate transmission, a first sprocket is provided on the rotation shaft of the first turntable, and a second sprocket having the same number of teeth as the first sprocket is provided on the rotation shaft of the second turntable. A sprocket may be provided, and a chain or a timing belt may be wound around the first and second sprockets.

A gear train for transmitting the rotation in the direction opposite to the rotation direction of the first turntable to the rotation axis of the second turntable while maintaining the rotation amount of the rotation shaft of the first turntable as it is. It may be.

Further, the first turntable and the second turntable may be driven synchronously by independent motors.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of the present invention will be described with reference to the drawings. First, a description will be given with reference to FIG. 1 which is a top view of the rotary stage according to the embodiment, and FIG. 2 which is a partial front sectional view of FIG.

In these figures, a driving means (not shown) places an arrow A on the fixed base 1 in FIG.
In FIG. 2, a moving base 3 is provided which is moved in a direction perpendicular to the plane of the drawing. In the moving base 3,
A rotary stage 5, which is a first rotary table, is rotatably provided.

The rotary shaft 7 of the rotary stage 5 is connected to a DD (direct drive) motor 9 provided in the moving base 3. The rotation stage 5 has a position eccentric from the rotation center of the rotation stage 5, and in this embodiment, on a circumference centered on the rotation center of the rotation stage 5,
Three wafer stages 13, which are second rotating tables on which the wafers 11 are placed, are rotatably provided.

Between the rotation axis 7 of the rotation stage 5 and the rotation axis 15 of each wafer stage 13, the rotation amount of the rotation axis 7 of the rotation stage 5 is kept as it is, and the rotation amount of the rotation axis 7 of the rotation stage 5 is changed. Transmission means T for transmitting rotation in the opposite direction to the rotation shaft 15 of each wafer stage 13 is provided.

In this embodiment, this transmission means T is
First pulley 2 provided on rotating shaft 7 of rotating stage 5
1, provided on a rotation shaft 15 of each wafer stage 13;
A second pulley 23 having the same diameter as the first pulley 21;
And a belt 25 wound around a second pulley 23.

The wafer 1 is located above the rotary stage 5.
1 is provided with a lens barrel 31 that emits a charged particle beam. The operation of the above configuration will be described.

The driving means (not shown) drives the charged particle beam EB emitted from the lens barrel 31 to irradiate one of the wafers 11 placed on the three wafer stages 13. The rotating stage 5 moves in a direction indicated by an arrow A in FIG. 1 and in a direction perpendicular to the plane of FIG.

Then, for example, as shown in FIG.
The charged particle beam EB emitted from the lens barrel 31 is
While irradiating the position B, the DD motor 9 is driven to rotate the rotary stage 5 in the positive direction (the direction of arrow E) or in the negative direction (the direction of the opposite arrow E). Perform

At this time, the transmission means T causes each wafer stage 13 to rotate by the same rotation amount as the rotation amount of the rotation shaft 7 of the rotation stage 5 and in the direction opposite to the rotation direction of the rotation shaft 7 of the rotation stage 5. Do.

Similarly, the rotary stage 5 is moved with respect to the fixed base 1 in the direction of arrow A, and while the charged particle beam EB emitted from the lens barrel 31 is irradiated onto the positions C and D of the wafer 11, the DD motor 9 is rotated. When the rotary stage 5 is rotated in the positive direction and the negative direction (the direction of arrow E) to perform a predetermined inspection and exposure on the wafer 11, the trajectory of the charged particle beam EB on the wafer 11 is shown in FIG.
(b). In FIG. 3 (b), the trajectories are displayed discretely, but they are actually drawn continuously.

When the DD motor 9 is driven and the rotary stage 5 is rotated to perform inspection and exposure on another wafer 11, the direction of the wafer 11 on the wafer stage 13 is shown in FIG. It does not change.

According to the rotary stage having the above configuration, the following effects can be obtained. (1) High-speed inspection and high-speed exposure equal to or higher than the conventional rotary stage are possible.

(2) Even if the rotary stage 5 rotates, the direction of the wafer 11 on each wafer stage 13 does not change, so that it is easy to correct the defect coordinates due to the alignment failure by parallel movement or the like.

(3) Even if the rotary stage 5 rotates, the direction of the wafer 11 on each wafer stage 13 does not change, so that the captured image does not rotate. Therefore, there is no need to perform rotation in image processing with a pattern.

(4) Even if the rotary stage 5 rotates, the direction of the wafer 11 on each wafer stage 13 does not change, so that Die-to-Die comparison is possible, and defect inspection of a wafer with a random pattern is possible. .

(5) Since the Die-to-Die comparison function can be realized, defect inspection can be performed even if the absolute position accuracy of the stage is poor. Note that the present invention is not limited to the above embodiment. In the above embodiment, the transmission means T is composed of a pulley and a belt. Alternatively, a first sprocket is provided on the rotating shaft 7 of the rotating stage 5, and the rotating shaft 15 of the rotating stage 5 is A second sprocket having the same number of teeth as the first sprocket may be provided, and a chain or a timing belt may be wound around the first and second sprockets.

In this case, there is no slip in the transmission.
Accurate transmission can be obtained. Furthermore, the rotary stage 5
The rotation amount of the rotation shaft 7 is not changed and the rotation stage 5
The gear train may transmit the rotation in the direction opposite to the rotation direction to the rotation shaft 15 of each wafer stage 13. Also in this case, since there is no slip in the transmission, accurate transmission can be obtained.

Similarly, the present invention can be realized by using a motor that rotates in the opposite direction at the same rotation angle as the rotation axis of the rotation stage 5 instead of the rotation axis of the wafer stage 13.

[0031]

As described above, according to the present invention, the first
The rotation amount of the rotation shaft of the turntable is kept as it is, and the transmission means for transmitting the rotation in the direction opposite to the rotation direction of the first turntable to the rotation shaft of the second turntable is provided. Even if the turntable rotates, the direction of the second turntable is maintained in a fixed direction.

Therefore, the direction of the wafer can be maintained in a fixed direction.

[Brief description of the drawings]

FIG. 1 is a top view of a rotary stage according to an embodiment.

FIG. 2 is a partial front sectional view of FIG. 1;

FIG. 3 is a view for explaining the operation of the rotary stage shown in FIG. 1;

FIG. 4 is a view for explaining the operation of the rotary stage shown in FIG. 1;

[Explanation of symbols]

 5 Rotary stage (first rotary table) 11 Wafer 13 Wafer stage (second rotary table) 15 Rotary axis T Transmission means

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 5C001 AA06 CC04 CC06 5C034 BB06 BB07 5F031 CA02 KA08 KA12 LA13 MA27 MA33

Claims (2)

[Claims] A first rotary table rotatably provided; and a plurality of second rotary tables rotatably provided at a position eccentric from a rotation axis of the first rotary table and on which a wafer is mounted. Table, the rotation amount of the rotation axis of the first turntable as it is, and
A transmission means for transmitting a rotation in a direction opposite to a rotation direction of the first turntable to a rotation shaft of the second turntable. 2. The power transmission means, comprising: a first pulley provided on a rotation shaft of the first turntable; and a transmission shaft provided on a rotation shaft of the second turntable, and having a diameter of the first pulley. 2. The rotary stage according to claim 1, comprising: a second pulley having the same diameter; a belt wound around the first pulley; and the second pulley.