JP4888859B2 - Proximity exposure equipment - Google Patents

Description

The present invention relates to a proximity exposure apparatus used in the manufacturing process of a semiconductor or a liquid crystal display device, and more specifically, an air current is generated in a gap between an exposure photomask and an exposure surface of an object to be exposed, and is generated during exposure. The present invention relates to an exposure apparatus that does not cause exposure failure due to adhesion of a product or the like to an exposure photomask.

A color filter or the like of a liquid crystal display device is a photomask in which a photomask is brought close to a glass substrate (hereinafter simply referred to as “substrate”) coated with a resist, and exposure light is irradiated to the substrate through the photomask. The pattern is transferred onto the substrate, but a product due to a chemical reaction generated at that time adheres to the photomask, and the photomask is contaminated.
The contamination of the photomask may reduce the light transmittance of exposure light at the contaminated portion and may not be optimally exposed. Therefore, the photomask is periodically cleaned (Patent Document 1), A method (Patent Document 2) such as supplying an inert gas between the substrate and the substrate is performed.

However, in the above correction method (the former), since the photomask is periodically removed from the exposure apparatus and cleaned, it is necessary to repeat the work of setting the photomask, and the alignment work at the time of mask setting is complicated. was there.
Further, in the method of supplying an inert gas between the photomask and the substrate in the correction method (the latter), the gap between the photomask and the substrate is not fixed from the fixed end side in a state where the photomask and the substrate are fixed. Since the active gas is supplied, there is a problem that the photomask cannot be continuously exposed while moving relative to the object to be exposed.

In particular, in the proximity exposure method, since the distance between the substrate and the photomask is generally about 100 μm, it is difficult to supply a sufficient inert gas between the photomask and the substrate, which increases the size of the substrate. There are problems that cannot be addressed.

Furthermore, when an inert gas is supplied between the photomask and the substrate, the air around the photomask is sucked between the mask and the substrate due to the airflow generated between the photomask and the substrate. There has been a problem that dust or the like on the surface of the object to be exposed is sucked between the photomask and the substrate to cause exposure failure.
JP 2004-342826 A Japanese Patent Laid-Open No. 2003-122019

The present invention has been made in view of the above circumstances, and provides a proximity exposure apparatus that has a simple structure, prevents contamination of a photomask during step exposure and continuous exposure, and can perform appropriate exposure. is there.

The present invention is characterized by the following points in order to solve the above problems.
That is, the proximity exposure apparatus according to claim 1 is a proximity exposure apparatus that performs exposure continuously while the exposure photomask moves relative to the object to be exposed, and is directed toward the exposure surface of the object to be exposed. The gas is supplied from the end in the direction in which the exposure photomask advances relative to the object to be exposed, and the direction opposite to the direction in which the exposure photomask advances relative to the object to be exposed A first airflow passing between the lower surface of the exposure photomask and the object to be exposed, and from the end side toward the outside of the exposure photomask, the direction of the first airflow It is characterized by generating a second airflow and a vortex in the opposite direction.

The proximity exposure apparatus according to claim 2 is a proximity exposure apparatus in which exposure is continuously performed while a photomask for exposure moves relative to the object to be exposed , and the exposure photomask faces the exposure surface of the object to be exposed. Gas is supplied from an end side in a direction in which the exposure photomask advances relative to the object to be exposed, and exposure is performed in a direction opposite to the direction in which the exposure photomask advances relative to the object to be exposed. A first airflow passing between the lower surface of the photomask for exposure and the object to be exposed is generated, and the direction of the first airflow is opposite from the end side toward the outside of the exposure photomask. A second airflow and a vortex flow are generated in the direction, and the gas of the first airflow is sucked from the other end side.

The present invention has the following excellent effects.
According to the first aspect of the present invention, since the first air flow is generated in the direction opposite to the moving direction of the photomask, the gas between the photomask and the exposed surface of the object to be exposed is moved by the movement of the photomask. While being ventilated more quickly, the product due to the chemical reaction does not stay between the lower surface of the exposure photomask (hereinafter simply referred to as “photomask”) and the exposed surface of the object to be exposed. Therefore, contamination of the photomask by this product can be prevented.
The eddy current of the second airflow generated in the photomask traveling direction makes it easy for the dust on the exposed surface of the exposed object in the photomask moving direction to be peeled off from the exposed surface, and the dust is more accurately removed. Therefore, it is possible to prevent the dust from adhering to the photomask and the resulting exposure failure.

According to the second aspect of the present invention, the suction device is connected from the downstream side of the first air stream, and the gas between the lower surface of the photomask and the exposed surface of the object to be exposed is easily discharged. Reaction products and the like due to exposure between the lower surface of the photomask and the exposed surface of the object to be exposed are easily discharged, and the photomask can be more easily prevented from being stained.

Hereinafter, a proximity exposure apparatus according to an embodiment of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a conceptual diagram showing a proximity exposure apparatus 1 according to an embodiment of the present invention.

The exposure apparatus 1 includes an object to be exposed (hereinafter simply referred to as “work”) 2, a table 3 on which the work 2 is placed, a photomask 4 for exposing the work 2 to a predetermined pattern, and a photomask 4. A mask holder 5 that holds the substrate in proximity to the panel substrate 2, an exposure light source 6 for irradiating the workpiece 2 with exposure light via the photomask 4, and an inert gas such as nitrogen gas on the mask holder 5. A gas supply device 7 for supplying gas, a vacuum pump 8 for sucking and discharging the inert gas from a part of the mask holder 5, a table driving device 9 for driving the table 3, a light source 6, a vacuum pump 8, and a driving device And a control device 10 for controlling 9. The exposure apparatus 1 is provided with various means such as a position detection means for measuring the positions of the photomask 4 and the work 2. However, since it is not the gist of the present invention, description thereof is omitted.

For example, as shown in FIG. 2, the work 2 includes a glass substrate 2 a and an exposure surface (hereinafter simply referred to as “resist layer”) 2 b applied to the surface of the glass substrate 2 a. Then, an exposure pattern of a photomask 4 described later is transferred to the resist layer 2b by the light emitted from the light source 6, and the resist layer 2b is exposed to a predetermined level.
Then, the alignment of the exposure position of the workpiece 2 and the photomask 4 can be performed by the table driving device 9 connected to the control device 10. After the positioning is completed, the workpiece 2 is moved by the table driving device 9. It is movable at a constant speed in the direction of the arrow α (X direction) and the Y direction (direction perpendicular to the paper surface of FIG. 1).

As shown in FIG. 3, the photomask 4 includes a transparent substrate 4a and a light shielding film 4b formed on the surface of the transparent substrate 4a. The light shielding film 4b includes a light shielding film 4b as shown in FIG. An exposure pattern is provided in which a plurality of openings 4c through which exposure light is transmitted are arranged in parallel.
Then, the light from the exposure light source 6 is irradiated onto the exposure pattern, and the exposure pattern is transferred to the resist layer 2b of the workpiece 2.

As shown in FIG. 4B, the mask holder 5 has a symmetrical structure. The mask holder 5 has an opening 5A for fitting and holding the photomask 4 with the light-shielding film 4b on the lower side, and an inert gas as a work piece. 2 has an air supply port 5a sprayed toward the resist layer 2b, and an exhaust port 5b for exhausting gas between the work 2 and the photomask 4.
The air supply port 5a is a square hole in cross section formed by the wall surfaces 5a1, 5a2, 5a3, 5a4, and the exhaust port 5b is a square hole in cross section formed by the wall surfaces 5b1, 5b2, 5b3, 5b4. The Y-direction lengths of the air supply port 5a and the exhaust port 5b are the same as the Y-direction length W of the mask 4, respectively.

Further, a curved surface 5B1 connected to be substantially flush with the lower surface of the photomask 4 from the lower end of the wall surface 5a1 of the air supply port 5a and a lower surface of the photomask 4 connected to the lower end of the wall surface 5a2 of the air supply port 5a. In addition to the parallel flat surface 5C1, the curved surface 5B2 connected from the lower end of the wall surface 5b1 of the exhaust port 5b so as to be substantially flush with the lower surface of the photomask 4, and the lower end of the wall surface 5b2 of the exhaust port 5b. Further, it has a plane 5C2 parallel to the lower surface of the photomask 4.

Furthermore, the planes 5C1 and 5C2 are positioned above the lower surface of the photomask 4 (the surface facing the workpiece 2) in the vertical direction (Z direction) of the workpiece 2, and the side surfaces 5D1, 5E1 and 5D2 are respectively provided. Air gaps 5F1 and 5F2 (FIGS. 5A and 5B) are formed together with 5E2.

With the above configuration, as shown in FIG. 6, the inert gas supplied from the inert gas supply device 7 to the supply port 5a through the supply tube 7a, the distribution pipe 7b, and the gas supply port 5d. Flows toward the work 2 and the spread in the Y-axis direction is restricted by the side surfaces 5D1 and 5E1 of the gap 5F1, and a part flows toward the curved surface 5B1 and the rest flows toward the flat surface 5C1.
The gas flowing toward the curved surface 5B1 flows between the lower surface of the photomask 4 and the surface of the resist layer 2b of the work 2, and flows toward the exhaust port 5b together with the reaction products and the like due to exposure.
The gas flowed to the exhaust port 5b side, the reaction product, and the like are discharged to the gap 5F2 (FIG. 5B) side and exhausted from the distribution pipe 8b connected to the gas suction port connected to the exhaust port 5b. The suction device 8 sucks and discharges through the tube 8a.

In addition, the airflow flowing to the flat surface 5C1 side is separated at the connection portion between the wall surface 5a2 of the air supply port 5a and the flat surface 5C1 to generate an overcurrent (the center of the vortex is substantially parallel to the wall surface 5a2). Due to the overflow, dust or the like placed on the surface of the resist layer 2 is wound up from the surface of the resist layer 2, so that dust or the like can be easily removed.
Then, since the gas of the overflow b circulates to form a so-called dead water region, the flow path of the gas flowing to the flat surface 5C1 side is narrowed, the amount of gas flowing to the curved surface 5B1 side increases, and the photomask 4 Reaction products and the like due to exposure can be better eliminated from between the lower surface and the resist layer 2b of the workpiece 2.

The exposure light source 6 incorporates a shutter (not shown), and the light source and the shutter are connected to the controller 10 so that the controller 10 can control the light amount, the irradiation time, and the like according to the exposure conditions of the workpiece 2. .

The exposure light source 6 and the mask holder 5 can be moved close to and away from the workpiece 2 in the Z direction integrally by lifting means (not shown) connected to the controller 10. It can be located at a position in the Z direction.
In the present embodiment, the gap between the surface of the resist layer 2b of the work 2 and the lower surface of the photomask 4 is maintained at about 100 μm.

The control device 10 is connected to the exposure light source 6 and the built-in shutter (not shown), and the gas supply device 7, the suction device 8, and the table drive device 9. The device can be controlled.

Next, regarding the operation of the exposure apparatus 1 configured as described above, first, the case of exposure of the color filter of the liquid crystal display substrate will be described based on the operation flowchart shown in FIG.
First, before operating the exposure apparatus 1, the work 2 is placed at a predetermined position on the table 3.
Next, in step 1 (S1), the table driving means 9 is operated to place the photomask 4 above the work 2 exposure start position obtained by the position detection means (not shown), and then the elevation movement (not shown) is performed. By means of this, the photomask 4 is positioned in the Z direction so that the gap between the lower surface of the photomask 4 and the surface of the resist layer 2b is predetermined.

Next, in step 2 (S2), the inert gas supply device 7 and the suction device 8 are operated to form a first air current C between the lower surface of the photomask 4 and the resist layer 2b, and photo The mask 4 generates a second air flow b and an overflow b along the work 2 in the forward direction.

Next, in step 3 (S3), the exposure light source 6 is actuated to start exposure of the resist layer 2b of the work 2 and get on the surface of the resist layer 2b of the work 2 ahead of the photomask 4 in the traveling direction. The table driving device 9 is operated while the dust that has been removed is removed by the second air flow b and the overflow b, and the work 2 is moved relatively continuously at a constant speed in the α direction with respect to the photomask 4. .
At that time, the shutter built in the exposure light source 6 is opened and closed by the control device 10 as necessary.

In step 4 (S4), after the exposure of the resist layer 2b in the predetermined exposure region of the work 2 is completed, the suction device 8 is stopped, and then the inert gas supply device 7 is stopped. , The photomask 4, the mask holder 5, and the exposure light source 6 are integrally separated from the work 2 in the Z direction, and then the table driving device 3 is operated to return to the initial position of the step 1. The table is returned to finish the work 2 exposure operation.

In step 4 (S4), after the exposure of the resist layer 2b in the predetermined exposure region of the work 2 is completed, the suction device 8 is stopped and then the inert gas supply device 7 is stopped. This is to prevent dust or the like around the mask holder 5 from being sucked into the surface of the resist layer 2b of the workpiece 2 later.

The reason why the lifting / lowering device is operated after the inert gas supply device 7 is stopped is that an appropriate suction force acts between the photomask 4 and the work 2 by the first airflow C. When the photomask 4, mask holder 5, and exposure light source 6 are integrally moved away from the work 2 in the Z direction by operating the lifting device (not shown), a force for lifting the work 2 from the table 3 is applied. This is because an unnecessary force is applied to the work 2 so that the unnecessary force is not applied to the work 2.

In the above embodiment, the inert gas is used, but air may be used instead of the inert gas. That is, when the length L in the traveling direction of the photomask 4 is shorter than the length W in the direction perpendicular to the traveling direction, the reaction product or the like due to the exposure is promptly generated from the lower surface of the photomask 4 by the first air current c. Since it is easily excluded, the lower surface of the photomask 4 is not easily soiled even when air is used.
When the photomask 4 having a length L in the traveling direction shorter than the length W in the direction perpendicular to the traveling direction is used, the gas between the lower surface of the photomask 4 and the surface of the resist layer 2b of the workpiece 2 is removed. Since ventilation is easy, it is not necessary to suck the gas between the lower surface of the photomask 4 and the surface of the resist layer 2b of the workpiece 2 by the suction device 8.

Furthermore, in the above embodiment, the Z-direction position of the plane 5C1 of the mask holder 5 is set to be higher than the lower surface of the photomask 4. However, the Z-direction position between the plane 5C1 and the lower surface of the photomask 4 is substantially the same. Even if it is the same, it goes without saying that the first airflow and the second airflow as in the above-described embodiment are generated except for the overflow b.

As described above, according to the proximity exposure apparatus according to the present invention, since the inert gas supply port 5a is provided on the mask holder 5 outside the photomask 4, the relative exposure to the workpiece 2 outside the photomask 4 is achieved. The dust in the traveling direction of the mask 4 caused by the first airflow can be prevented from being drawn into the lower surface of the mask 4 by the second airflow generated forward in the direction of movement.
Further, since the inert gas supply port or the like is not directly provided in the photomask itself as in Patent Document 2, the exposure pattern of the photomask is not restricted by the inert gas supply port, and various photomasks are used. it can.

It is a conceptual diagram which shows the proximity exposure apparatus which concerns on one embodiment of this invention. It is a conceptual diagram which shows the cross section of a workpiece | work. It is explanatory drawing explaining the structure of a photomask. BRIEF DESCRIPTION OF THE DRAWINGS It is a conceptual diagram which shows the photomask and mask holder of the proximity exposure apparatus which concern on one embodiment of this invention, Comprising: (a) is the plane schematic diagram of the state which mounted | wore the mask holder, (b) is ( It is the schematic which shows the A'-A 'cross section of a). 4A and 4B are schematic views of β and γ arrows, FIG. 4A is a schematic diagram of β arrows, and FIG. 4B is a schematic diagram of γ arrows. It is explanatory drawing for demonstrating the relationship of the airflow between a workpiece | work, a photomask, and a mask holder. It is a flowchart explaining operation | movement of a proximity exposure apparatus in one embodiment of this invention.

1: proximity exposure apparatus 2 according to one embodiment: work 3: table 4: photomask 5: mask holder 6: exposure light source 7: inert gas supply device 8: suction device 9: table driving device 10: control device

Claims (2)

A proximity exposure apparatus that continuously exposes an exposure photomask while moving relative to the object to be exposed, wherein the exposure photomask faces the exposure surface of the object to be exposed. A gas is supplied from an end side in a relatively advancing direction, and the lower surface of the exposure photomask and the object to be exposed are opposite to the direction in which the exposure photomask advances relatively to the object to be exposed. And a second air current and a vortex in a direction opposite to the direction of the first air current from the end side toward the outside of the exposure photomask. Proximity exposure apparatus characterized in that A proximity exposure apparatus that continuously exposes an exposure photomask while moving relative to the object to be exposed, wherein the exposure photomask faces the exposure surface of the object to be exposed. A gas is supplied from an end side in a relatively advancing direction, and the lower surface of the exposure photomask and the object to be exposed are opposite to the direction in which the exposure photomask advances relatively to the object to be exposed. And a second air current and a vortex in a direction opposite to the direction of the first air current from the end side toward the outside of the exposure photomask. And a proximity exposure apparatus that sucks the gas of the first air stream from the other end side.