JPH09251203A - Exposing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent blurring from partially occurring in the projection of a photomask pattern with respect to a photoresist film. SOLUTION: This device is at least provided with a placing plate 3 and the photomask 1, and the plate 3 is arranged, so that a substrate coated with the photoresist film 5 abuts on a placing surface. And also as to the photomask 1, the peripheral part of the photomask 1 is supported so that the photomask 1 is arranged to face oppositely to the surface coated with the film 5. In this case, deflection is formed on the placing surf ace of the plate 3 in accordance with the amount of the deflection due to the gravity of the photomask 1.

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 example, an exposure apparatus used in manufacturing a liquid crystal display substrate.

[0002]

2. Description of the Related Art For example, in a liquid crystal display device, wirings, electrodes, semiconductor elements, etc. which are finely etched by a so-called photolithography technique are formed on the liquid crystal side surface of each transparent substrate which is arranged to face each other with a liquid crystal interposed therebetween. There is.

That is, when a conductive layer having a predetermined pattern is formed on the main surface of a transparent substrate, a metal layer is formed on the entire main surface of the transparent substrate, and a photoresist film is further formed on the entire surface of the metal layer. Form.

On the other hand, there is a photomask on which the pattern of the conductive layer is drawn, and the photomask is arranged so as to face the surface of the transparent substrate on which the photoresist film is formed.

Then, the photoresist of the transparent substrate is selectively exposed through the photomask to expose the photoresist film according to the pattern.

After that, the exposed portion of the photoresist film is removed by a developing solution, for example. Then, using the remaining photoresist film as a mask, the metal layer exposed from the photoresist film is etched by using an appropriate etching solution.

Then, by removing all of the photoresist film, a conductive layer having a predetermined pattern can be obtained.

Here, when selective exposure is performed on the photoresist film through the photomask, a transparent substrate is set on a mounting table having a flat surface, and one of the mounting table and the photomask is moved. By doing so, the photoresist film on the transparent substrate surface and the photomask are made to face each other with a very small gap.

By thus bringing the photomask close to the photoresist film on the transparent substrate surface, the fine pattern on the photomask is clearly projected on the photoresist film surface without so-called "blur". .

[0010]

However, when selective exposure is performed on the photoresist film using such an exposure apparatus, the photomask pattern is partially but partially referred to as "blur". It was confirmed that the image was projected onto the surface of the photoresist film, and as a result, the cut as a mask was not good at the part where the blur occurred (the boundary between the part where the photoresist film was present and the part where the photoresist film was not present was dull). It means that) is pointed out.

As a result of pursuing this cause, when a photomask having a relatively large area is arranged in a supported state around the photomask, the center portion of the photomask is largely bent by its own weight. It was discovered that the gaps in the area would not be uniform.

The present invention has been made under these circumstances, and an object thereof is to provide an exposure apparatus which prevents partial blurring in the projection of a pattern of a photomask onto a photoresist film. Especially.

[0013]

SUMMARY OF THE INVENTION Among the inventions disclosed in the present application, the outline of a representative one will be briefly described.
It is as follows.

Means 1. At least a mounting table and a photomask are provided, and the mounting table is arranged such that a substrate having a photoresist film coated on the mounting surface is placed in contact with the mounting table, and the photomask has its periphery. Is supported and is arranged to face the surface of the substrate coated with the photoresist film, the mounting surface of the mounting table is formed with a recess corresponding to the amount of deflection of the photomask due to gravity. It is characterized by that.

Means 2. In the configuration of the means 1, the mounting surface of the mounting table is formed by the surfaces of the tops of the plurality of scattered vertically movable protrusions, and the mounting surface of the protrusions is embedded in the tops of the protrusions. A sensor for detecting a gap amount, and a control mechanism for performing fine vertical movement of the protrusion based on a detection output of the photomask of the sensor to make a gap between the protrusion and the photomask uniform. It is characterized by.

Means 3. At least a mounting table and a photomask are provided, and the mounting table is arranged such that a substrate having a photoresist film coated on the mounting surface is placed in contact with the mounting table, and the photomask has its periphery. In the exposure apparatus which is arranged to face the surface of the substrate on which the photoresist film is coated, the mounting surface of the mounting table is a surface of the tops of a plurality of scattered vertically movable fine projections. And a sensor that is embedded in the top of each of the protrusions or is disposed near each of the protrusions to detect a gap amount with the photomask, and a detection output of the photomask of the sensor. And a control mechanism for performing fine vertical movements of the protrusions based on the surface of the tops of the protrusions to form a recess corresponding to the amount of deflection of the photomask due to gravity. Than it is.

According to the exposure apparatus configured as the means 1, the gap between the photoresist film on the substrate mounted on the mounting surface of the mounting table and the photomask is made uniform on the opposing surfaces thereof. be able to.

Therefore, the projection of the pattern of the photomask onto the photoresist film can be made clear in all parts.

Therefore, it is possible to prevent partial blurring in the projection of the pattern of the photomask on the photoresist film.

According to the exposure apparatus configured as the means 2, when the recess formed according to the bending of the photomask on the mounting surface of the mounting table is not always accurately formed due to the limitation of the processing accuracy. Will be able to adjust.

According to the exposure apparatus configured as the means 3, the deflection corresponding to each of the transparent substrates is detected for each substrate to be mounted separately, and the mounting surface of the mounting surface is detected according to the detection result. The surface shape of the depression is changed.

Therefore, it can be applied to all substrates having slightly different flexural rigidity, and it is possible to prevent partial blurring in the projection of the pattern of the photomask onto the photoresist film.

[0023]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiment 1. FIG. 1 is a block diagram showing an embodiment of an exposure apparatus according to the present invention, and particularly shows an exposure apparatus used in manufacturing a liquid crystal display substrate.

In the figure, first, there is a photomask 1, and this photomask 1 has a fine mask pattern 1B made of chromium formed on one surface of a transparent substrate 1A. The photomask 1 is fixed to a base (not shown) by being attached to the mask holder 2.

The photomask 1 has a rectangular shape which is slightly larger than the glass substrate constituting the liquid crystal display substrate to be processed, and the mask holder 2 excludes the central portion of the photomask 1 where the mask pattern 1B is formed. It has an annular shape that attaches only the peripheral part.

Here, the photomask 1 is attached to the mask holder 2 by adopting a method of fixing almost the entire periphery of the photomask 1 to the mask holder 2 in the figure, but the method is not limited to this. Instead, a method of simply supporting it may be adopted.

In this case, the photomask 1 has a relatively large shape. This is because it is formed so as to correspond to the size of the glass substrate in the liquid crystal display substrate.

From this, the photomask 1 cannot avoid the occurrence of bending due to its own weight, as shown in FIG.

The upper portion of the photomask 1 supported by the mask holder 2 is irradiated with uniform parallel light from, for example, an ultrahigh pressure mercury lamp (not shown), and this light is emitted from the photomask 1. Among them, the light is transmitted through the light transmitting portion where the mask pattern 1B is not formed, and the lower portion of the photomask 1 is irradiated with the light.

A mounting table 3 is arranged below the photomask 1, and one glass substrate 4 of a liquid crystal display substrate to be processed is mounted on the mounting table 3. The glass substrate 4 has a photoresist film 5 formed on its entire surface by, for example, rod coater coating.

Here, as shown in the figure, the mounting surface of the mounting table 3 is formed with a recess corresponding to the bending of the photomask 1. The so-called bending curved surface in the bending of the photomask 1 has a property that is uniquely determined by the material and thickness of the photomask 1, the attachment method (fixing or supporting) to the mask holder 2, and the like. FIG. 3 is a graph showing the deflection amount of the center (vertical axis) with respect to the thickness (horizontal axis) of the arbitrarily selected photomask according to the attachment to the mask holder 2, and also from this graph. As is apparent, it turns out that the curved curved surface can be specified.

Therefore, the recess of the mounting table 3 can be accurately formed in accordance with the above purpose.

The mounting surface of the mounting table 3 is provided with a decompression hole 6 for exhausting the atmosphere between it and the glass substrate 4 mounted thereon. The substrate 4 is adapted to be closely fixed (vacuum chuck) to the mounting table 3.

Therefore, the glass substrate 4 is recessed in accordance with the recess of the mounting table 3, and the recess corresponds to the bending of the photomask 1.

Here, the mounting table 3 is positioned below the mask holder 2 with a relatively large distance in the figure, but this is because the glass substrate 4 is not obstructed by the mask holder 2. This is because it can be mounted on the mounting table 3.

Therefore, the mounting table 3 can be lifted by driving a mechanism (not shown).
As shown in FIG. 2, the mounting table 3 is positioned in the mask holder 2 so that the glass substrate 4 mounted on the mounting table 3 is brought close to the photomask 1.

At this stage, the mask pattern 1B of the photomask 1 is formed on the photoresist film 5 on the surface of the glass substrate 4 by irradiation of uniform parallel light from the ultra-high pressure mercury lamp.
Selective exposure is performed according to.

In this case, since the gap between the photoresist film 5 on the surface of the glass substrate 4 and the photomask 1 is uniform over the entire area, the projection of the mask pattern 1B of the photomask 1 onto the photoresist film 5 is partial. There is no blur and the result is extremely clear.

FIG. 4 is an explanatory view showing details of the selective exposure of the photoresist film 4. As shown in the figure,
It is undeniable that the light transmitted through the light transmitting portion of the photomask 1 may include light that is slightly deviated from the parallel light even if the ultra-high pressure mercury lamp that is the exposure source is parallel light. Due to the light, the projection onto the photoresist film 4 does not match the mask pattern of the perfect photomask 1.

In order to reduce this effect as much as possible, it is needless to say that the profit gap is made as small as possible, and the profit gap is made uniform so that the part where the gap is partially small or many is large. To lose.

According to the embodiment described above, the gaps between the photoresist film 5 on the glass substrate 4 mounted on the mounting surface of the mounting table 3 and the photomask 1 are all uniform on their opposing surfaces. Therefore, the projection of the pattern of the photomask 4 onto the photoresist film 5 can be made clear in all parts.

Therefore, it is possible to prevent partial blurring in the projection of the pattern of the photomask 1 on the photoresist film 5.

In the above-mentioned embodiment, the entire mounting surface of the mounting table 3 is provided with a recess corresponding to the bending surface of the photomask 1. However, the present invention is not limited to this, and as shown in FIG. 5, on the mounting surface side of the mounting table 3,
Providing a plurality of scattered protrusions 3A, each protrusion 3
It is needless to say that a recess corresponding to the bending surface of the photomask 1 may be formed at the top of A.

Further, as shown in the figure, when each projection 3A is formed separately and these projections 3A are fixed to the mounting table 3, there is an effect that the manufacture thereof is simplified. Like

Example 2. FIG. 6 is a configuration diagram showing another embodiment of the exposure apparatus according to the present invention.

This drawing shows a further improved construction of the exposure apparatus shown in FIG. 5 of the first embodiment.

First, each projection 3A of the mounting table 3 is constructed so that its base is embedded in the mounting table 3 and that it can be slightly moved in the vertical direction by the drive mechanism 3C via the rod 3B. ing.

As the drive mechanism 3C in this case, for example, a part of the rod 3B may be a worm, and a gear meshing with the worm may be rotated by a pulse motor or the like.

On the other hand, a sensor 3d is provided on the top of each projection 3A.
Is embedded, and the sensor 3d can detect the distance from the position of the sensor 3d to the photomask 1 that is arranged to face it.

As the sensor 3d in this case, for example, an ultrasonic sensor that oscillates and receives ultrasonic waves can be selected.

The outputs from the respective sensors 3d are input to the control device 7. In this control device 7, each sensor 3d determines whether or not the distance from that position to the photomask 1 is uniform, and if there is a non-uniform portion, the height of the protrusion 3A at that portion is increased. The height can be adjusted by the drive mechanism 3C.

According to such an embodiment, it is possible to make an adjustment when the recess formed on the mounting surface of the mounting table 3 in accordance with the bending of the photomask is not always accurately formed due to the limitation of the processing accuracy. The effect of becoming like this comes to be exhibited.

Embodiment 3 FIG . The exposure apparatus shown in the second embodiment is
It is configured to accurately adjust the recess of the mounting table 3 formed in advance according to the bending of the photomask 1.

However, in the same configuration, when the photomask is used by substituting it with another photomask 1 having a different material, thickness, or a mounting method for the mask holder 1, the output from each sensor 3d is used. The deflection pole surface of the photomask 1 may be calculated by the control device 7, and then each drive device 3c may be driven according to the calculated value.

As a result, the height of each projection 3A changes, and it becomes possible to form a recess corresponding to the bending surface of the photomask 1 at each top thereof.

According to the exposure apparatus constructed as in the above-described embodiment, the flexure corresponding to each substrate is detected for each substrate to be mounted separately, and the mounting surface is detected according to the detection result. It is possible to change the surface shape of the dent.

In order to obtain such an effect, the sensor 3d does not have to be provided on the top of the projection 3A, and may be formed on the mounting table 3 on which the projection 3A is not arranged. If the distance from each sensor 3d provided on such a reference surface to the photomask 1 is known, the bending surface of the photomask 1 is calculated, and the protrusion 3A is calculated accordingly.
This is because the control device 7 can determine how high the height should be.

Further, although the sensor 3d is provided in the above-described embodiment, data corresponding to the type of the photomask 1 to be replaced is stored in the control device 7 in advance,
Even if the control device 7 sets the height of the projection 3A according to this data, the same effect can be obtained.

[0059]

As is apparent from the above description,
With the exposure apparatus according to the present invention, it is possible to prevent partial blurring in the projection of the pattern of the photomask onto the photoresist film.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of an exposure apparatus according to the present invention, showing one mode of its operation.

FIG. 2 is a block diagram showing an embodiment of an exposure apparatus according to the present invention, showing another mode of its operation.

FIG. 3 is an explanatory diagram for explaining that the deflection of a photomask used in the exposure apparatus according to the present invention can be specified.

FIG. 4 is an explanatory diagram for explaining effects of the exposure apparatus according to the present invention.

FIG. 5 is a configuration diagram showing another embodiment of the exposure apparatus according to the present invention.

FIG. 6 is a configuration diagram showing another embodiment of the exposure apparatus according to the present invention.

[Explanation of symbols]

1 ... Photomask, 1B ... Mask pattern, 2 ...
Mask holder, 3 ... Mounting table, 3A ... Projection, 3d ...
... Sensor, 4 ... Glass substrate, 5 ... Photoresist film.

Claims (5)

[Claims] 1. A mounting table and a photomask are provided at least, and the mounting table is arranged such that a substrate coated with a photoresist film is brought into contact with the mounting surface of the mounting table. In the exposure apparatus in which the periphery of the mask is supported and is arranged to face the surface of the substrate coated with the photoresist film, the mounting surface of the mounting table depends on the deflection amount of the photomask due to gravity. An exposure apparatus having a recess formed therein. 2. The mounting surface of the mounting table is formed by the surfaces of the tops of a plurality of scattered vertically movable fine projections, and is embedded in the tops of the respective projections or the projections. A sensor that is disposed in the vicinity of each of the photomasks and detects the amount of the gap with the photomask, and performs fine vertical movement of the protrusion based on the detection output of the photomask of the sensor, and the gap between the photomask and the protrusion 2. The exposure apparatus according to claim 1, further comprising a control mechanism for making the above uniform. 3. A mounting table and a photomask are provided at least, and the mounting table is arranged such that a substrate coated with a photoresist film is brought into contact with the mounting surface of the mounting table, and In an exposure apparatus in which the periphery of the mask is supported and faces the surface of the substrate coated with the photoresist film, the mounting surface of the mounting table has a plurality of scattered vertically movable fine projections. A sensor that is formed by the surface of the top of the body, is embedded in the top of each protrusion, or is arranged in the vicinity of each protrusion to detect the gap amount with the photomask; and a sensor of this sensor. And a control mechanism for performing fine vertical movements of the protrusions based on the detection output of the mask to form a recess corresponding to the amount of deflection of the photomask due to gravity on each surface of the top of each protrusion. And an exposure apparatus. 4. A depressurizing hole for exhausting the atmosphere between the mounting table and the substrate mounted on the mounting table is provided in the mounting surface. The exposure apparatus according to any one of 1. 5. The transparent substrate in the manufacture of a liquid crystal display substrate having a transparent substrate which is arranged to face each other with a liquid crystal interposed therebetween as an envelope, wherein the transparent substrate is the transparent substrate.
The exposure apparatus according to any one of 2, 3, and 4.