JP2001044097A - Aligner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent air at the outside of the outer circumferential wall from flowing into the inside of the inner circumferential wall by constructing the sucking section of the inner circumferential wall and the outer circumferential wall surrounding the inner circumferential wall, forming the inner circumferential wall of a rigid material and forming the outer circumferential wall of a plastic member at least on the forward end side being bonded to a fixed plate. SOLUTION: A suction section 10 provided on a substrate holder has a double structure of one inner circumferential wall 11 providing a closed region, and one outer circumferential wall 12 surrounding the inner circumferential wall 11. The inner circumferential wall 11 is formed of a rigid material, e.g. stainless steel. The outer circumferential wall 12 has a two-layer structure, where the base part side 12a secured to the substrate holder 2 is formed of a rigid material, e.g. stainless steel, and the forward end side 12b being boded to a fixing plate 3 is made of a plastic material, e.g. silicon rubber, wherein the plastic material can be replaced as required. A pressure- reducing tube 5 for evacuating only the inside of the inner circumferential wall 11 is passed through the outer circumferential wall 12 and is connected with the inner circumferential wall 11.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exposure apparatus for printing a fine pattern on a substrate such as a liquid crystal display and a semiconductor device, and more particularly, to an exposure device provided on a substrate holder for holding a substrate, the suction unit being provided near the substrate holder. The present invention relates to an exposure apparatus which is vacuum-sucked on a fixed plate arranged in such a manner that a substrate and a photomask face each other in an accurate positional relationship.

[0002]

2. Description of the Related Art To form a fine pattern on a substrate such as a liquid crystal display or a semiconductor device, an exposure apparatus as shown in FIG. 2 is used. In this exposure apparatus, a frame-shaped suction portion 4 is provided on an upper surface of a substrate holder 2 for holding a substrate 1 coated with a photoresist on a surface thereof, which is vacuum-adsorbed to a fixing plate 3 arranged near the substrate holder 2. ing. The substrate holder 2 can move in the vertical direction and the horizontal direction. By moving upward, the upper surface of the suction unit 4 is joined to the lower surface of the fixed plate 3. The suction portion 4 is formed of a metal having almost rigidity in order to suppress the slight vibration of 1 μm or less and to be pressed against the fixing plate 3. Further, a vacuum tube 5 connected to a vacuum pump (not shown) is attached to the suction unit 4 to exhaust the inside of the suction unit 4 to a vacuum state.

Further, a photomask 6 having a pattern formed thereon is disposed above the substrate 1 held by the substrate holder 2. The fixing plate 3 includes a substrate 1 and a photomask 6.
A window portion 3a is formed so that the window 3a can face. In two places at each end of the substrate 1 and the photomask 6,
Marks 1a and 6a for alignment (alignment) with an accuracy of at most 1 to 2 μm in both the vertical and horizontal directions are provided.

In order to print a pattern on the substrate 1 by the exposure apparatus configured as described above, first, as shown in FIG. 3, the substrate holder 2 holding the substrate 1 moves in the horizontal direction, and the substrate 1 is moved. It is made to face the photomask 6. Then, as shown in FIG. 4, the substrate 1 and the marks 1a, 6a of the photomask 6 are viewed from above in a state where the substrate holder 2 moves upward and the upper surface of the suction unit 4 is joined to the lower surface of the fixing plate 3. The suction unit 4 is evacuated by the decompression tube 5 to reduce the pressure to a vacuum state. Then, the suction section 4 is vacuum-sucked to the fixed plate 3, and the substrate holder 2 is fixed to the fixed plate 3. Then, when the substrate 1 is exposed to the ultraviolet light transmitted through the photomask 6, a fine pattern is printed on the substrate 1. The substrate 1 on which the pattern is printed is sent to a post-process for manufacturing a liquid crystal display or a semiconductor device.

[0005]

The fixing plate 3 is formed of a metal having a substantially rigidity, and the suction portion 4 provided on the upper surface of the substrate holder 2 is also formed of a metal having a substantially rigidity. . When the surface where the suction part 4 is joined to the fixing plate 3 is scratched, and dust adheres,
Even if the adsorbing section 4 and the fixing plate 3 are joined, a gap is formed between the adsorbing section 4 and the fixing plate 3.
Even if the inside is evacuated, the air outside the suction section 4 flows into the suction section 4 from this gap, and the inside of the suction section 4 does not reach the required vacuum pressure.

[0006] Then, the suction part 4 is not vacuum-sucked to the fixed plate 3, the substrate holder 2 is not fixed to the fixed plate 3, and the alignment between the substrate 1 and the photomask 6 is not performed. As a result, the desired pattern cannot be printed on the substrate 1, and the quality of the liquid crystal display or the semiconductor device deteriorates.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an exposure apparatus in which a suction portion is pressed and a substrate and a photomask face each other in an accurate positional relationship.

[0008]

According to a first aspect of the present invention, there is provided a first exposure apparatus which holds a substrate having a surface coated with a photoresist, and moves the held substrate to face a photomask; In an exposure apparatus provided on a substrate holder and having a frame-shaped suction portion that is vacuum-sucked to a fixing plate disposed near the substrate holder, the suction portion is a closed region that is brought into a vacuum state. An inner peripheral wall provided, and an outer peripheral wall surrounding the inner peripheral wall, wherein the inner peripheral wall is formed of a rigid material, and the outer peripheral wall is formed of a plastic material at least on a distal end side to be joined to the fixed plate. Is what you do.

According to this exposure apparatus, a closed area is formed in the inner peripheral wall and between the inner peripheral wall and the outer peripheral wall in a state where the suction portion is joined to the fixed plate. The inside of the inner peripheral wall is exhausted in a state where the surface where the inner peripheral wall formed of the rigid material is joined to the fixing plate is scratched or dust adheres, and a gap is generated between the inner peripheral wall and the fixing plate. Thus, when the pressure is reduced, a limited amount of air in the closed region between the inner peripheral wall and the outer peripheral wall flows into the inner peripheral wall. Since the outer peripheral wall formed of the plastic material is also joined to the fixed plate, air outside the outer peripheral wall does not flow from the outer peripheral wall into the inner peripheral wall. Therefore, the inside of the reduced inner peripheral wall is in a vacuum state, and the inner peripheral wall formed of the rigid material is securely pressed against the fixed plate.

A second exposure apparatus according to the present invention is the first exposure apparatus, wherein the suction portion has a double structure including one inner peripheral wall and one outer peripheral wall. It is assumed that.

According to this exposure apparatus, the suction section has a double structure of the inner peripheral wall and the outer peripheral wall, so that one closed region is formed between the inner peripheral wall and the outer peripheral wall, and the inner peripheral wall is fixed to the inner peripheral wall. If a gap is formed between the plate and the plate, only air in the closed area flows into the inner peripheral wall.

A third exposure apparatus according to the present invention is the first or second exposure apparatus, wherein a decompression tube for exhausting only an inner peripheral wall of the suction section is connected to the inner peripheral wall. Is what you do.

According to this exposure apparatus, since the decompression tube is connected to the inner peripheral wall, the air in the region between the inner peripheral wall and the outer peripheral wall is exhausted, and the pressure in the region is not reduced. In addition, the inner peripheral wall made of the rigid material is securely pressed against the fixed plate without the outer peripheral wall formed of the plastic material being pressed against the fixed plate.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An exposure apparatus according to the present invention will be described with reference to FIG. However, the same parts as those in the related art are denoted by the same reference numerals, and description thereof will be omitted.

The exposure apparatus of the present invention comprises a suction portion 10 provided on a substrate 1 holder, which is constituted by one inner peripheral wall 11 providing a closed area and one outer peripheral wall 12 surrounding the inner peripheral wall 11. And a double structure. The inner peripheral wall 11
For example, it is formed of a rigid material such as stainless steel (SUS343). Further, the outer peripheral wall 12 has a base side 12a fixed to the substrate holder 2, for example, made of stainless steel (SUS34).
3) A two-layer structure of a rigid material as in 3) and a plastic material such as silicone rubber on the tip side 12b to be joined to the fixing plate 3 is provided so that the plastic material can be replaced as appropriate. A decompression tube 5 for exhausting only the inside of the inner peripheral wall 11 to make a vacuum state is connected to the inner peripheral wall 11 through the outer peripheral wall 12.

The exposure apparatus of the present invention is configured as described above, and the method of use will be described next. Also in the exposure apparatus of the present invention, when the substrate holder 2 holding the substrate 1 moves, the upper surface of the suction unit 10 and the lower surface of the fixed plate 3 are joined, and the inner wall 11 and the inner wall 11 and the outer wall 12 are joined. And a closed area is provided between them. Then, alignment is performed such that the marks 1a and 6a of the photomask 6 and the substrate 1 held by the substrate holder 2 overlap when viewed from above. Next, the suction unit 1 is moved by the pressure reducing tube 5.
The pressure is reduced by evacuating the inner peripheral wall 11 of zero.

When there is no flaw on the surface of the inner peripheral wall 11 joined to the fixing plate 3 and no dust is attached, no gap is formed between the inner peripheral wall 11 and the fixing plate 3. The inside of the peripheral wall 11 is brought into a vacuum state by being decompressed. Therefore, the upper surface of the inner peripheral wall 11 formed of a rigid material is securely pressed against the lower surface of the fixing plate 3, and the substrate holder 2 is fixed to the fixing plate 3, and the substrate 1 held by the substrate holder 2 And the photomask 6 are aligned with high accuracy.

On the other hand, if the upper surface of the inner peripheral wall 11 of the suction section 10 is scratched or dust is attached,
A gap is formed between the upper surface of the fixing plate 3 and the fixing plate 3. At this time,
A limited amount of air in a closed area between the inner peripheral wall 11 and the outer peripheral wall 12 flows into the inner peripheral wall 11 from this gap. However, since the upper surface of the distal end side 12b of the outer peripheral wall 12 made of a plastic material is joined to the fixed plate 3, the outer peripheral wall 1
The outside air does not flow into the inner peripheral wall 11 from the outer peripheral wall 12.

Therefore, the upper surface of the inner peripheral wall 11 of the suction section 10 is scratched or dust adheres, and
Even if a gap is formed between the upper surface of the inner peripheral wall 11 and the fixing plate 3, the inner peripheral wall 11 and the outer peripheral wall 1 are depressurized.
After a limited amount of air between the inner peripheral wall 11 and the inner peripheral wall 11 flows into the inner peripheral wall 11, the inner peripheral wall 11 is in a vacuum state. Then, the inner peripheral wall 11 formed of a rigid material is brought into pressure contact with the fixing plate 3, and the substrate 1 held by the substrate holder 2 and the photomask 6 are aligned with high accuracy.

Further, the decompression tube 5 only evacuates the inner peripheral wall 11 of the adsorbing section 10 to reduce the pressure, but does not exhaust the area between the inner peripheral wall 11 and the outer peripheral wall 12. Therefore, the pressure in the inner peripheral wall 11 is first reduced, and then the inner peripheral wall 11 and the outer peripheral wall 12 are depressurized.
Is depressurized, so that the upper surface of the inner peripheral wall 11 made of a rigid material is always secured to the lower surface of the fixed plate 3 regardless of whether or not the upper surface of the inner peripheral wall 11 is flawed. And the substrate holder 2 is fixed to the fixing plate 3. For reference, a vacuum tube is
In the case where the inner peripheral wall 11 and the inner peripheral wall 11 are connected to each other between the inner peripheral wall 11 and the outer peripheral wall 12 to perform decompression in parallel, if the gap between the upper surface of the inner peripheral wall 11 and the fixing plate 3 is large,
It is mainly in a state of being sucked and fixed by the outer peripheral wall 12. In such a case, since the tip of the outer peripheral wall 12 is made of a plastic material, the suction and fixation of the substrate holder 2 to the fixing plate 3 becomes uncertain, and a problem arises that high-precision alignment cannot be performed during exposure. In this regard, in the present invention, since the decompression tube 5 only exhausts the pressure in the inner peripheral wall 11 of the suction section 10 to reduce the pressure, the upper surface of the inner peripheral wall 11 formed of the rigid material as described above is The substrate holder 2 is firmly pressed on the lower surface of the substrate, and the substrate holder 2 is fixed to the fixing plate 3, so that highly accurate alignment can always be achieved.

Further, since the outer peripheral wall 12 is provided so as to surround the inner peripheral wall 11, dust around the outer peripheral wall 12 is sucked into the outer peripheral wall 12 by joining the outer peripheral wall 12 to the fixing plate 3. This makes it difficult for the upper surface of the inner peripheral wall 11 to be scratched or for dust to adhere.

The substrate 1 thus aligned is exposed to ultraviolet light transmitted through the photomask 6, and an intended fine pattern is printed.

The present invention is not limited to the above embodiments of the present invention, and various modifications can be made within the technical scope described in the claims of the present invention. For example, the inner peripheral wall and the outer peripheral wall may have a triple structure or more. The outer peripheral wall is made of a rigid material and a plastic material.
Instead of a layered structure, all may be made of a plastic material. Further, although the drawing shows a case where the suction portion is provided only at one place of the substrate holder, it may be provided at a plurality of places.

[0024]

According to the present invention, since the adsorbing portion is constituted by the inner peripheral wall of the rigid material and the outer peripheral wall of the plastic material, the surface where the inner peripheral wall is joined to the fixing plate has scratches or dust. Even if there is a gap between the inner peripheral wall and the fixed plate due to the adhesion, only the limited air between the inner peripheral wall and the outer peripheral wall flows into the inner peripheral wall, and the necessary vacuum pressure is generated in the inner peripheral wall. The secured, inner peripheral wall of the rigid material is pressed against the fixed plate. Therefore, a fine pattern is accurately printed on a substrate manufactured by the exposure apparatus of the present invention, and the quality of a liquid crystal display device or a semiconductor device including the substrate can be improved.
Further, the throughput is increased as compared with the related art.

Further, since the outer peripheral wall made of a plastic material is joined to the fixing plate, dust can be prevented from being sucked into the outer peripheral wall. Therefore, it is possible to prevent the inner peripheral wall of the suction portion from being easily scratched and to prevent dust from adhering.

[Brief description of the drawings]

FIG. 1 is a schematic perspective view of a main part of an exposure apparatus of the present invention.

FIG. 2 is a schematic perspective view of a conventional exposure apparatus.

FIG. 3 is a front sectional view of a stage before exposure by a conventional exposure apparatus.

FIG. 4 is a front sectional view of a stage when exposure is performed by a conventional exposure apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Substrate 2 ... Substrate holder 3 ... Fixing plate 5 ... Decompression tube 10 ... Adsorption part 11 ... Inner peripheral wall 12 ... Outer peripheral wall 12b ... Tip side

Claims (3)

[Claims] A substrate holder for holding a substrate having a surface coated with a photoresist and moving the held substrate so as to face a photomask; a substrate holder mounted on the substrate holder; and disposed near the substrate holder. An exposure apparatus having a frame-shaped suction portion that is vacuum-sucked to a fixed plate, wherein the suction portion includes an inner peripheral wall that provides a closed region that is brought into a vacuum state, and an outer peripheral wall that surrounds the inner peripheral wall. An exposure apparatus, wherein the inner peripheral wall is formed of a rigid material, and the outer peripheral wall is formed of a plastic material at least on a front end side joined to a fixed plate. 2. The exposure apparatus according to claim 1, wherein the suction section has a double structure including one inner peripheral wall and one outer peripheral wall. 3. The exposure apparatus according to claim 1, wherein a decompression tube for exhausting only an inner peripheral wall of the suction section is connected to the inner peripheral wall.