JP3287058B2 - Exposure equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a projection exposure apparatus used for manufacturing semiconductor elements and liquid crystal display substrates, and more particularly to a transfer apparatus for transferring a mask having a pattern to be exposed from a storage place to an exposure position. It is about.

[0002]

2. Description of the Related Art A conventional apparatus of this kind has a configuration as shown in FIG. That is, a reticle (not shown) mounted on the reticle stage 5 is illuminated by a light beam from an illumination optical system (not shown), and an image of a pattern on the reticle is projected onto the plate stage 7 via the projection optical system PL. It is projected on the plate P. This exposure apparatus is configured to detect the position of a reticle by an alignment optical system (not shown). In order to position the reticle with respect to the optical axis of the projection optical system PL, the reticle stage 5 is positioned based on the detection result of the alignment optical system.

On the other hand, a plurality of reticles (not shown) used for exposure are stored in the reticle library 1 in individual cases. The fork 2 arranged so as to be able to enter the reticle library 1 takes out a required reticle from the case of the reticle library 1 and
Alternatively, unnecessary reticle is stored in reticle library 1. In the transport path from the reticle library 1 to the reticle stage 5, a pre-alignment mechanism 3 for roughly aligning the reticle is provided. Others
The load arm 4A for loading the reticle onto the reticle stage 5, and the load arm 4A moves independently of the load arm 4A in the Y direction in the figure and integrally with the load arm 4A in the Z direction in the figure. And an unload arm 4B for unloading.

The fork 2 is responsible for transporting the reticle from the reticle library 1 to the pre-alignment mechanism 3. The transport (loading) from the pre-alignment mechanism 3 to the reticle stage 5 is performed by the load arm 4A and the reticle stage. The unload arm 4B and the fork 2 are responsible for carrying (unloading) from the reticle library 5 to the reticle library 1, respectively.

First, the reticle in the reticle library 1 is taken out of the reticle library 1 with a fork 2,
It is transported to the pre-alignment mechanism 3. The pre-alignment mechanism 3 roughly aligns the reticle on the fork 2 with a predetermined position, and
Receive 1 Next, the load arm 4A receives the reticle from the pre-alignment mechanism 3, and transfers the reticle to the reticle stage 5. When the reticle is mounted on the reticle stage 5, alignment is performed based on an alignment optical system (not shown), and the plate P is exposed.

When the exposure is completed, the unload arm 4B
Receives the reticle from the reticle stage 5 and stores it in the reticle library 1 via the fork 2. Then, a new reticle is unloaded from the reticle library 1 and placed on the reticle stage 5 in the same manner as described above.
The exposure is repeated.

[0007]

In the prior art as described above, except for the reticle mounted on the reticle stage, only one reticle can exist in the transport path. In the exposure process, exposure is often performed while frequently changing reticle, and reticle exchange in the conventional apparatus is inefficient. In order to shorten the reticle replacement time, it is conceivable to increase the moving speed of each of the fork, the load arm, and the like, but there is a limit to the reduction of the replacement time that can be performed by that method.

SUMMARY OF THE INVENTION An object of the present invention is to provide an exposure apparatus having a high throughput by efficiently exchanging the reticle of the exposure apparatus.

[0009]

In order to solve the above-mentioned problems, an exposure apparatus according to an embodiment of the present invention will be described with reference to the accompanying drawings. ), A substrate stage (5) for holding the substrate at a predetermined position, a substrate storage means (1), and a substrate stage (5).
Board transfer means (2, 4A, 4) for transferring a board between
B) and a preliminary positioning means (3) provided in a transport path by the substrate transport means (2, 4A, 4B) and roughly positioning the substrate at a predetermined position, A substrate stage (5) which holds a plurality of substrates integrally and moves to a predetermined position.
And a temporary storage unit (8) for temporarily storing the substrate positioned by the preliminary positioning unit (3). The exposure apparatus according to claim 2, wherein during the exposure by the first set of the plurality of substrates held by the substrate exchange means (3), the second set of the other plurality of substrates is stored in the substrate storage means (1). ) And carry out pre-positioning means (3)
Transport control means for storing the data in the temporary storage unit (8) via the first storage means and exchanging the first set and the second set by the substrate transfer means (2, 4A, 4B) when the exposure by the first set is completed. (CNT). According to a third aspect of the present invention, there is provided the exposure apparatus, wherein the substrate exchange means (6, 9) includes a precise positioning means for precisely positioning each of the plurality of substrates individually at a predetermined position. The exposure apparatus according to claim 4, wherein the plurality of reticles stored in the reticle storage means (1) are sequentially conveyed to a reticle stage (5), and a pattern is exposed on a substrate using the plurality of reticles. A temporary storage means (8) provided between the reticle storage means (1) and the reticle stage (5) for temporarily storing a predetermined reticle among the plurality of reticles; and a temporary storage means (8). )
And a holding means (6) provided between the reticle stage (5) and the reticle stage (5). In the exposure apparatus according to the fifth aspect, the holding means (6) includes transport means (6A, 6B, 6C) for transporting the reticle to and from the reticle stage (5). 7. An exposure apparatus according to claim 6, wherein the pattern is exposed on the substrate by using a plurality of reticles stored in the reticle storage means, and a pattern to be exposed among the plurality of reticles. Reticle stage (9) for holding a plurality of reticles each having a reticle, and temporary storage provided between reticle storage means (1) and reticle stage (9) for temporarily storing a predetermined reticle among the plurality of reticles. Means (8). An exposure apparatus according to claim 7, wherein the reticle stage holds a plurality of reticles.
And a control device (CNT) for controlling the driving of the motor.

[0010]

According to the present invention, there is provided a reticle transport system of an exposure apparatus having a reticle changer for exchangeably holding a plurality of reticles required for exposure on a reticle stage.
Because a storage is provided to prepare and temporarily store a new reticle during exposure by the reticle held by the reticle changer, the transport path required for reticle replacement is only between the reticle changer and the storage. Since reticle exchange preparation can be efficiently performed, comprehensive reticle exchange can be promptly performed.

[0011]

FIG. 1 is a diagram showing a schematic configuration of a projection exposure apparatus according to a first embodiment of the present invention. A reticle (not shown) mounted on the reticle stage 5 is illuminated by a light beam from an illumination optical system (not shown), and an image of a pattern on the reticle is transmitted to the plate stage 7 via the projection optical system PL.
It is projected on the upper plate P. This exposure apparatus is configured to detect the position of a reticle by an alignment optical system (not shown). Further, in order to position the reticle with respect to projection optical system PL, reticle stage 5 is positioned based on the detection result of the alignment optical system.

On the other hand, a plurality of reticles (not shown) R1, R2, R3,... Used for exposure are stored in the reticle library 1 in individual cases. The fork 2 arranged so as to be able to enter the reticle library 1 takes out a necessary reticle from the case of the reticle library 1 or stores an unnecessary reticle in the reticle library 1. A pre-alignment mechanism 3 for roughly aligning the reticle in a transport path from the reticle library 1 to the reticle stage 5;
A storage 8 for temporarily storing a plurality of reticles is provided. In addition, a load arm 4A for loading a reticle onto the reticle stage 5, a load arm 4A in the Y direction in the drawing, and a load arm 4A in the Z direction in the drawing.
And a unload arm 4B for unloading the reticle from the reticle stage 5.

The fork 2 is in charge of transporting the reticle between the reticle library 1 and the pre-alignment mechanism 3 and transporting the reticle from the storage 8 to the reticle library 1.
Alternatively, the transfer to the storage 8 and the transfer from the storage 8 to the reticle stage 5 are performed by the load arm 4A, and the transfer from the reticle stage 5 to the storage 8 is performed by the unload arm 4B. Also, these forks 2,
The operations of the load arm 4A, the unload arm 4B, and the reticle changer 6 are controlled by the controller CNT. Further, the controller CNT
It is connected to an exposure control device (not shown) that controls a shutter and a stage 7 of the illumination optical system, and is configured to control the reticle changer 6 and the like according to an exposure command output from the exposure control device.

After the reticle mounted on the reticle stage 5 is positioned, it is transferred to the reticle holding portions 6A to 6C of the reticle changer 6 while maintaining this position, and is mounted on the reticle stage 5 again as necessary. Is placed. In the example of the exposure apparatus shown in FIG. 1, three reticles are placed on the reticle changer 6.
Consider three reticles as one set.

The reticle transport operation in the above-described apparatus will be described with reference to FIG. First, the reticle R1 in the reticle library 1 is taken out of the reticle library 1 with the fork 2 and transported to the pre-alignment mechanism 3 (step 101). The pre-alignment mechanism 3
The reticle R1 on the fork 2 is roughly aligned with a predetermined position, and the reticle R1 is received from the fork 2 (step 102).

Next, the load arm 4A receives the reticle R1 from the pre-alignment mechanism 3, and transfers the reticle R1 to the reticle stage 5 (step 103). Once the reticle R1 is mounted on the reticle stage 5, once it is determined whether the reticle is mounted on all the reticle holders of the reticle changer, a predetermined value is determined based on an alignment optical system (not shown). The reticle R1 on the stage 5 is aligned with a position (a position that should be positioned with respect to the projection optical system PL at the time of exposure) (step 104). At this time, the fork 6 of the reticle changer that can move within a predetermined stroke in the X direction and the Z direction in the drawing is at the lower end of the stroke in the Z direction, and the reticle holding unit 6A is at the access position (reticle position) with the reticle stage 5. Delivery position).

Here, it is determined whether the reticle R1 currently mounted on the stage 5 is the last reticle for the reticle changer (step 105). In this case, since the reticle is still the first reticle, the process proceeds to step 106 and the reticle is placed on the holding portion on the reticle changer. That is, when the fork 6 moves up in the Z direction, the reticle R1 is received from the reticle stage 5 onto the reticle holding section 6A, and stops at the upper end of the stroke. Next, the fork 6 moves in the X direction and stops at the position where the reticle holding unit 6B comes to the access position with the reticle stage 5. Then, descend to the lower end of the stroke in the Z direction,
Preparation for receiving the next reticle R2 is completed.

As described above, the reticle is mounted on the reticle changer in the same manner as described above until the last reticle for the reticle changer is mounted on the stage.
That is, the second reticle R2 is stored in the reticle holding unit 6B in the same procedure as the first reticle R1. However, it is more efficient to perform the operations from Step 101 to Step 102 in parallel with the operations from Step 103 onward. Then, after the result of the determination in step 105 is negative, the operation of step 103 can be performed immediately.

On the other hand, if it is determined in step 105 that the reticle is the last reticle, the process proceeds to step 107 to perform exposure. At the time of exposure, a necessary reticle is
Exposure to the plate P is performed by transferring from A to 6C to the reticle stage 5. In the above case, since the reticle R3 is mounted on the stage 5, it is efficient to perform exposure from this reticle R3. .

While the exposure is being performed using the reticles R1 to R3, it is determined whether or not there is a reticle to be used (to be prepared) for the subsequent exposure (step 10).
8) If present, the reticle (in this case, reticle R4
R6) is prepared in the storage 8. That is, reticle R4
Is taken out of the reticle library 1 by the fork 2 (step 109) and transported to the pre-alignment mechanism 3. The pre-alignment mechanism 3 aligns the reticle R4 on the fork 2 with a predetermined position (step 110) and receives the reticle R4 from the fork 2.

Next, the load arm 4A receives the reticle R4 from the pre-alignment mechanism 3, and determines whether the reticle R4 currently mounted on the load arm 4A is the last reticle to be prepared (step 11).
1). In this case, since the reticle is still the first reticle, the process proceeds to step 112 to store the reticle R4 in the first storage location 8A in the storage 8. In the same operation, R
5 is stored in the second storage space 8B. On the other hand, if it is determined in step 111 that the reticle is the last reticle, the apparatus waits while holding the reticle on the load arm 4A (step 113). That is, after the reticle R6, which is the remaining when the three reticles are formed as one set, is aligned by the pre-alignment mechanism 3 as described above, the exposure of the reticles R1 to R3 is completed while being received by the load arm 4A. Wait until.

When it is determined in the next step 114 that the exposure is completed, the reticle (for example, reticle R1) mounted on the reticle stage 5 at that time is taken out by the unload arm 4B and moved in the Y direction, and the reticle is moved. It stops at the reference position (the position shown by the broken line in the figure) on the library 1 side (step 115). After the reticle R1 is carried out of the reticle stage 5, the load arm 4A holding the reticle R6 moves in the Y direction to the reticle stage 5, transfers the reticle R6 to the reticle stage 5, and returns to the reference position (step 116). . After that, the unload arm 4B moves in the Z direction together with the load arm 4A, stops at the transfer height to the third storage area of the storage 8, and enters the storage 8 to store the third storage area. The reticle R1 is stored in 8C.

Load arm 4 not holding reticle
A moves in the Z direction to the reticle transfer height with respect to the second-stage storage location 8B, enters the storage 8, and receives the reticle R5. Here, the unload arm 4B rises in the Z direction together with the load arm 4A, and stops at the transfer height with respect to the reticle stage 5. At this time, the reticle R2 already held on the reticle holding section 6B is placed on the reticle stage 5. Thereafter, the reticles R2 and R3 are stored in the storage locations 8B and 8A, respectively, in the same manner as described above.
B, reticles R5 and R4 stored in storage area 8A
To the reticle holding units 6B and 6C. With the above operation, the exchange of the reticles R1 to R3 for which exposure has been completed and the reticles R4 to R6 to be used for the next exposure is completed.

After it is determined in step 117 that the reticle exchange has been completed, exposure is performed with reticles R4 to R6, and during that time, reticles R1 to R3 are stored in reticle library 1 (step 118). If there is a reticle to be further prepared (step 119), the reticle may be prepared in the same manner as described above during exposure of reticles R4 to R6. The reticles to be prepared in the storage 8 during exposure by the reticles R1 to R3 are R4 to R6. However, if there is sufficient time, the next reticle may be further prepared in the storage. .

FIG. 2 is a diagram showing a schematic configuration of an exposure apparatus according to a second embodiment of the present invention. In this configuration, the reticle changer and the reticle stage are integrally formed, and the reticle stage 9 is moved in the X direction in the drawing while the reticle is mounted on each of the reticle holding units 10A to 10C on the reticle changer 9. Moving. That is, there is no need to transfer the reticle between the reticle changer and the reticle stage as in the apparatus shown in FIG. The reticle is a reticle holding unit 10A to 10C.
And is transferred between the load arm 4A and the unload arm 4B. Otherwise, the configuration is the same as that of the apparatus shown in FIG. In the second embodiment, since the delivery between the reticle changer 6 and the reticle stage 5 in the first embodiment can be omitted, the time required for reticle exchange is further reduced.

[0026]

As described above, the exposure apparatus according to any one of the first to third aspects is provided with the substrate exchange means and the temporary storage unit, so that the substrate transfer path at the time of substrate exchange is shortened, and the substrate exchange time is reduced. Can be shortened. Further, since a substrate required for the next exposure can be prepared during the exposure, the substrate can be transported efficiently. Since the exposure apparatus according to the fourth and fifth aspects includes the temporary storage unit and the holding unit, the transport path at the time of reticle exchange is shortened, and the reticle exchange time can be shortened. Since the exposure apparatus according to the sixth and seventh aspects includes the reticle stage and the temporary storage means, the transport path at the time of reticle exchange is shortened, and the reticle exchange time can be shortened.

[Brief description of the drawings]

FIG. 1 is a diagram showing a schematic configuration of an exposure apparatus according to a first embodiment of the present invention.

FIG. 2 is a diagram showing a schematic configuration of an exposure apparatus according to a second embodiment of the present invention.

FIG. 3 is a flowchart showing an operation of the exposure apparatus according to the first embodiment of the present invention.

FIG. 4 is a diagram showing a schematic configuration of an exposure apparatus according to a conventional technique.

[Explanation of symbols]

 Reference Signs List 1 reticle library 2 fork 3 pre-alignment mechanism 4A load arm 4B unload arm 5 reticle stage 6,9 reticle changer 8 storage CNT controller

Claims (7)

(57) [Claims] 1. A substrate storage means for storing a plurality of substrates,
A substrate stage for holding the substrate at a predetermined position, a substrate transport unit for transporting the substrate between the substrate storage unit and the substrate stage, and a substrate provided in a transport path by the substrate transport unit; An exposure apparatus including preliminary positioning means for roughly positioning the substrate with respect to the predetermined position, wherein the plurality of substrates are integrally held, and the substrate is moved with respect to the predetermined position to move the substrate relative to the substrate stage. An exposure apparatus comprising: a substrate exchange unit for transferring a substrate; and a temporary storage unit for temporarily storing the substrate positioned by the preliminary positioning unit, in the transport path. 2. An exposure apparatus according to claim 1, wherein, during exposure by said first set of said plurality of substrates held by said substrate exchange means, said second set of other plurality of substrates is transferred from said substrate storage means. Carrying out, storing in the temporary storage unit via the preliminary positioning means, and exchanging the first set and the second set by the substrate transfer means when the exposure by the first set is completed. An exposure apparatus further comprising a control unit. 3. The apparatus according to claim 1, wherein said board exchange means includes precision positioning means for precisely positioning each of said plurality of substrates with respect to said predetermined position. Exposure equipment. 4. An exposure apparatus for sequentially transporting a plurality of reticles stored in a reticle storage means to a reticle stage and exposing a pattern on a substrate using the plurality of reticles, wherein the reticle storage means and the reticle. A temporary storage means provided between the temporary storage means and the reticle stage, and a reticle provided between the temporary storage means and the reticle stage and transported to the reticle stage; An exposure apparatus, comprising: holding means capable of holding a plurality of images. 5. An exposure apparatus according to claim 4, wherein said holding means includes a transport means for transporting said reticle to and from said reticle stage. 6. An exposure apparatus for exposing a pattern on a substrate using a plurality of reticles stored in a reticle storage means, wherein a plurality of reticles having the pattern to be exposed among the plurality of reticles are held. An exposure apparatus provided between the reticle storage means and the reticle stage, and a temporary storage means for temporarily storing a predetermined reticle among the plurality of reticles. 7. An exposure apparatus according to claim 6, further comprising a control device for driving and controlling a reticle stage holding said plurality of reticles.