JP2009134005A - Proximity exposure device and proximity exposure method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a proximity exposure device and a proximity exposure method, capable of improving exposure accuracy by surely preventing distortion of a mask through a relatively simple structure. <P>SOLUTION: In the proximity exposure device PE, an elastically deformable seal member 23 is provided on a work stage 1 so as to surround the circumference of a substrate W held thereon. The seal member 23 can contact with a held mask M held on a mask stage 2 when either one of the work stage 1 and the mask stage 2 is moved closer to each other so that the clearance between the mask M and the substrate W becomes an exposure gap g, and closely seals the clearance space between the mask M and the substrate W to raise the pressure in the clearance space higher than the pressure on the upper side of the mask M. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a proximity exposure apparatus and a proximity exposure method for performing proximity exposure of a mask pattern of a mask on a substrate of a flat panel display such as a liquid crystal display or a plasma display.

  Conventional proximity exposure apparatuses that manufacture color filters and the like for flat panel display devices such as liquid crystal display devices and plasma display devices hold the mask on the mask stage and hold the substrate on the work stage, and face each other close to each other. After the arrangement, the substrate is irradiated with light for pattern exposure from the mask side, whereby a plurality of mask patterns drawn on the mask are exposed and transferred onto the substrate. Here, since the thickness of the mask is very small with respect to the area, the bending due to the weight of the mask and the bending due to the change in inertia and the atmospheric pressure during the movement of the mask are likely to occur. For this reason, various ideas have been made as a technique for preventing the mask from bending (see, for example, Patent Documents 1 and 2).

  In the exposure apparatus described in Patent Document 1, in order to prevent bending due to the weight of the mask, in order to control the lower space of the mask to a positive pressure, the entire work stage including the substrate is sealed to be a positive pressure space, In order to control the space above the mask to a negative pressure, a method is shown in which the entire work stage including the substrate is sealed to be a negative pressure space, or the space above the mask is sealed to be a negative pressure space.

In addition, in the exposure apparatus described in Patent Document 2, a non-contact type seal member is arranged around the mask to control the lower space of the mask to a positive pressure, and the positive pressure generated by the movement of the substrate is used as the seal member. There is known a method of maintaining by an air curtain effect in which gas is discharged from.
Japanese Patent No. 2672535 JP 2007-41269 A

  By the way, in the exposure apparatus described in Patent Document 1, since it is necessary to make the entire work stage and the upper space of the mask a sealed space, it is difficult to adjust the pressure distribution formed in the space, and the sealed space is configured. There is a problem that good maintainability cannot be obtained due to the covers.

  In addition, in the exposure apparatus described in Patent Document 2, there is a possibility that the substrate and the mask come into contact with each other due to variations in pressure due to the gas discharged from the seal member, and the seal member may also come into contact with the substrate.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a proximity exposure apparatus and a proximity exposure method capable of reliably preventing the bending of the mask and improving the exposure accuracy with a relatively simple configuration. Is to provide.

The above object of the present invention is achieved by the following configurations.
(1) A work stage capable of holding a substrate as a material to be exposed, a mask stage arranged to face the substrate and capable of holding a mask, and irradiating the substrate with light for pattern exposure via the mask A proximity exposure apparatus comprising:
On the work stage, a seal member that is elastically deformable so as to surround the periphery of the held substrate is provided,
The seal member is capable of contacting the held mask when moving one of the work stage and the mask stage so that a gap between the mask and the substrate becomes an exposure gap, A proximity exposure apparatus, wherein a gap space between the mask and the substrate is sealed so that a pressure in the gap space is higher than a pressure above the mask.
(2) The height of the seal member is set based on an increase in pressure obtained by moving from the position where the mask and the seal member start to closely contact each other to the exposure position (1). ) Proximity exposure apparatus.
(3) It has a tube which communicates with the gap space via the seal member, and further has a pressure adjusting means capable of adjusting the pressure in the gap space via the tube (1) or The proximity exposure apparatus according to (2).
(4) The proximity exposure apparatus according to any one of (1) to (3), wherein the mask is larger than the substrate so as to face the seal member.
(5) A work stage capable of holding a substrate as a material to be exposed, a mask stage arranged to face the substrate and capable of holding a mask, and irradiating the substrate with light for pattern exposure via the mask. A proximity exposure method using a proximity exposure apparatus comprising: an irradiating means that is provided; and an elastically deformable seal member provided on the work stage so as to surround the periphery of the held substrate,
By moving one of the work stage and the mask stage so that the gap between the mask and the substrate is a predetermined distance, the seal member is brought into contact with the held mask, and the mask Sealing the gap space between the substrate and the substrate so that the pressure in the gap space is higher than the pressure above the mask;
A step of exposing and transferring the pattern of the mask onto the substrate by the irradiation means in a state where the gap between the mask and the substrate becomes the exposure gap;
A proximity exposure method comprising:

  According to the proximity exposure apparatus and the proximity exposure method of the present invention, a seal member that can be elastically deformed is provided on the work stage so as to surround the periphery of the substrate, and the seal member exposes a gap between the mask and the substrate. When one of the work stage and the mask stage is moved close to the gap, the mask can be brought into contact with the mask, and the gap space between the mask and the substrate is sealed, and the pressure in the gap space is adjusted to the upper side of the mask. Set higher than pressure. Thus, with a relatively simple configuration, the mask can be reliably prevented from bending and the exposure accuracy can be improved.

  Hereinafter, the proximity exposure apparatus and the proximity exposure method of the present invention will be described in detail with reference to the accompanying drawings.

  As shown in FIGS. 1 and 3, the proximity exposure apparatus PE of this embodiment includes a work stage 1 that holds a glass substrate (material to be exposed) W, a mask stage 2 that holds a mask M, and a pattern exposure tool. An illumination optical system 3 as an irradiating means and an apparatus base 4 that supports the work stage 1 and the mask stage 2 are provided.

  A glass substrate W (hereinafter simply referred to as “substrate W”) is placed on the mask M so as to be exposed to the surface (opposite surface of the mask M) so that the mask pattern P drawn on the mask M is exposed and transferred. An agent is applied to make it translucent.

  The work stage 1 includes a pair of guide rails 10 extending in the X-axis direction on the apparatus base 4, and a ball screw 12 extending in parallel with the guide rails 10 between the pair of guide rails 10 and driven by a motor 11. .

  A plurality of sliders 13 are movably provided on each guide rail 10, and a nut 14 is attached to the ball screw 12, and the plurality of sliders 13 and nuts 14 are attached to an X-axis stage 15. . Thereby, the X-axis stage 15 can be driven in the X-axis direction with respect to the apparatus base 4. As the drive mechanism, a linear motor may be provided instead of the ball screw mechanism.

  Further, between the X-axis stage 15 and the Z-axis stage 16, a Z-axis fine movement mechanism 17 composed of a movable wedge mechanism formed by combining a motor, a ball screw, and a wedge is disposed at one center in the Y direction and on both sides in the other end in the Y direction. It is provided at three places. Each Z-axis fine movement mechanism 17 rotationally drives a ball screw screw shaft 19 (see FIG. 3) by a motor 18, and a wedge 21 in which a slope of a nut 20 formed in a wedge shape projects from the lower surface of the Z-axis stage 16. Engage with the slope.

  Then, when the screw shaft 19 of the ball screw is driven to rotate, the wedge-shaped nut 20 is finely moved horizontally in the Y-axis direction, and this horizontal fine movement is converted into a highly accurate vertical fine movement by the slope action of both wedges 20 and 21. Is done. Each Z-axis fine movement mechanism 17 has a tilt function by being controlled independently, and is adjusted so that the mask M and the substrate W face each other in parallel.

  Further, the Z-axis stage 16 drives the work holder 22 in the Z-axis direction by a built-in actuator (not shown). The work holder 22 can place the substrate W on the upper surface and detachably hold the substrate W by vacuum suction or the like. Further, a seal member 23 that is elastically deformable so as to surround the periphery of the held substrate W is provided on the work holder 22.

  The mask stage 2 includes a mask stage base 30, and the mask stage base 30 is disposed above the work stage 1 while being supported by a column 31 protruding from the apparatus base 4.

  The mask stage base 30 has a substantially rectangular shape and has an opening 30a at the center, and a mask holding frame 32 is placed on the upper surface in the vicinity of the opening 30a. As a result, the mask holding frame 32 is inserted through the opening 30a of the mask stage base 30 via a predetermined gap, and can be moved in the X, Y axis directions and θ directions by a drive mechanism (not shown).

  A chuck portion 33 is fixed to the lower part of the mask holding frame 32, and the mask M is sucked and held on the lower surface of the chuck portion 33 by vacuum suction or the like. The mask M having a size larger than that of the substrate W is used so as to face the seal member 23 on the work holder 22. Although not shown, the mask holding frame 32 is provided with a gap sensor for detecting a gap between the opposing surfaces of the mask and the substrate, an alignment camera for adjusting the alignment between the mask and the substrate, and the like.

  Further, an illumination optical system 3 is provided above the mask stage 2, and the illumination optical system 3 includes a high-pressure mercury lamp that is a light source for ultraviolet irradiation, a concave mirror that collects light emitted from the high-pressure mercury lamp, There are provided two types of optical integrators, a plane mirror, a spherical mirror, and an exposure control shutter that is arranged between the plane mirror and the optical integrator and controls the opening and closing of the irradiation light path.

  At the time of exposure, the mask M is sucked and held on the mask stage 2, the substrate W is sucked and held on the work stage 1, and the work holder 22 located below the mask holding frame 32 is raised, so that the substrate W and the mask M are lifted. The substrate W is moved closer to the mask M until the gap between the opposing surfaces becomes the exposure gap g (see FIG. 2B). When the exposure control shutter is controlled to open, the light irradiated from the high-pressure mercury lamp passes through the optical path L to the surface of the mask M held on the mask stage 2 and eventually the substrate W held on the work stage 1. On the other hand, it is irradiated as parallel light for pattern exposure perpendicularly. Thereby, the mask pattern P of the mask M is exposed and transferred onto the substrate W.

  Here, when the work holder 22 is moved closer, the seal member 23 arranged on the work holder 22 starts to come into close contact with the mask M as shown in FIG. By bringing the gap between them close to the exposure gap g, as shown in FIG.

  As a result, when the work holder 22 is moved closer, the pressure of the gas between the mask M and the substrate W increases and a positive pressure is formed, and the center of the mask M is deformed so that it rises upward. Suppresses bending. Then, the pressure in the gap space between the mask M and the substrate W that is further sealed is increased by moving from the position where the mask M and the seal member start to contact to the exposure position. As a result, the pressure p1 in the gap space becomes higher than the pressure p2 on the upper side of the mask M, and the gap between the mask M and the substrate W is maintained uniformly and stably in a state where the bending of the mask M is cancelled.

  Accordingly, the height of the seal member 23 is set based on the pressure increase in the gap space obtained by moving from the position where the mask M and the seal member 23 start to closely contact each other to the exposure position. For this reason, the space design between the board | substrate W and the sealing member 23 is performed so that the clearance gap compressed by the deformation | transformation of the sealing member 23 may not become higher than a desired pressure.

  In this embodiment, an O-ring is used as the seal member 23, but it may be a lip seal that can be deformed to give a degree of freedom in the gap direction and the horizontal direction, or a hollow O-ring. -It may be a ring. In any of the seal members 23, it is necessary to shape the four corners so as to be rectangular when viewed from above.

  Here, when the first layer (such as a black matrix of a color filter) is exposed on the substrate W, it is not necessary to position the mask M with respect to the movement axis of the work stage as in step exposure, and simple alignment adjustment is performed. Only need.

  In addition, when exposing the second layer and subsequent layers (R, G, B layers of the color filter) on the substrate W, the mask M is set higher than the first layer of the substrate W by image recognition using an alignment camera. Position with precision.

  That is, as shown in FIG. 4, the seal member 23 needs to be arranged in parallel to the mask M aligned with the first layer BM of the substrate W. For this reason, in the case of the proximity exposure apparatus PE that exposes the second and subsequent layers, the seal member 23 is configured to allow horizontal movement with respect to the work holder 22. Of course, it is possible to expose the first layer BM using the proximity exposure apparatus PE shown in FIG.

  Therefore, according to the proximity exposure apparatus and the proximity exposure method of the present embodiment, the seal member 23 that is elastically deformable so as to surround the periphery of the substrate W is provided on the work stage 1. When the work stage 1 is moved closer so that the gap between the substrate W becomes the exposure gap, the mask M can be contacted, and the gap space between the mask M and the substrate W is sealed, and the gap space is sealed. Is made higher than the pressure above the mask M. Thereby, with a comparatively simple structure, the bending of the mask M can be reliably prevented and the exposure accuracy can be improved.

(Second Embodiment)
Next, a proximity exposure apparatus according to a second embodiment of the present invention will be described with reference to FIG. FIG. 5 shows only the main part of the proximity exposure apparatus of the present embodiment, and the same parts as those of the first embodiment are denoted by the same reference numerals, and description thereof is omitted or simplified.

  As shown in FIG. 5, in the proximity exposure apparatus of this embodiment, the work stage 1 has a tube 51 that communicates with the gap space via the seal member 23, and adjusts the pressure in the gap space via the tube 51. A pressure vessel 52 is provided as a possible pressure regulating means. Thereby, for example, when the substrate W moves up and down, deformation of the mask M can be suppressed and vibration of the mask M can be controlled. Further, the gas may be increased or decreased by the pressure vessel 52 in the gap space so that the gap space at the time of exposure becomes a desired pressure.

  Other configurations and operations are the same as those in the first embodiment. The pressure adjusting means may be constituted by a control valve, or may be constituted by an auxiliary tank.

In addition, this invention is not limited to each embodiment mentioned above at all, In the range which does not deviate from the summary, it can implement with a various form.
For example, in this embodiment, the mask M is sucked and held on the lower surface of the chuck portion 33 of the mask holding frame 32, but the mask M is disposed above the chuck portion 33 to prevent the mask M from falling. May be.
In the proximity exposure apparatus of the present invention, a laser length measurement system may be provided as necessary.

It is a side view which shows the proximity exposure apparatus which exposes the 1st layer of a color filter based on 1st Embodiment of this invention. (A) is a principal part enlarged view which shows the state which driven the work stage and the sealing member began to adhere | attach on a mask, (b) is an exposure clearance gap between a board | substrate and a mask, when a sealing member deform | transforms. It is a principal part enlarged view which shows the state which became. It is a side view which shows the proximity exposure apparatus which exposes the 2nd layer and subsequent layers of a color filter based on 1st Embodiment. It is a figure for demonstrating the horizontal movement of the sealing member at the time of aligning with high precision. It is a side view which shows the principal part of the proximity exposure apparatus which concerns on 2nd Embodiment of this invention.

Explanation of symbols

1 Work stage 2 Mask stage 3 Illumination optical system (irradiation means)
23 Seal member g Exposure gap M Mask P Mask pattern PE Proximity exposure apparatus W Glass substrate (material to be exposed)

Claims (5)

A work stage capable of holding a substrate as a material to be exposed, a mask stage disposed opposite to the substrate and capable of holding a mask, and irradiation means for irradiating the substrate with light for pattern exposure via the mask A proximity exposure apparatus comprising:
On the work stage, a seal member that is elastically deformable so as to surround the periphery of the held substrate is provided,
The seal member is capable of contacting the held mask when moving one of the work stage and the mask stage so that a gap between the mask and the substrate becomes an exposure gap, A proximity exposure apparatus, wherein a gap space between the mask and the substrate is sealed so that a pressure in the gap space is higher than a pressure above the mask.   The height of the seal member is set based on a pressure increase obtained by moving from a position where the mask and the seal member start to closely contact each other to the exposure position. Proximity exposure equipment.   3. The apparatus according to claim 1, further comprising a tube that communicates with the gap space through the seal member, and further includes a pressure adjusting unit that can adjust the pressure in the gap space through the tube. Proximity exposure equipment.   The proximity exposure apparatus according to claim 1, wherein the mask is larger than the substrate so as to face the seal member. A work stage capable of holding a substrate as a material to be exposed, a mask stage disposed opposite to the substrate and capable of holding a mask, and irradiation means for irradiating the substrate with light for pattern exposure via the mask And a proximity exposure method using a proximity exposure apparatus comprising an elastically deformable seal member provided on the work stage so as to surround the periphery of the held substrate,
The seal member is brought into contact with the held mask by moving one of the work stage and the mask stage so that a gap between the mask and the substrate becomes an exposure gap. Sealing the space between the substrate and making the pressure in the space higher than the pressure above the mask;
A step of exposing and transferring the pattern of the mask onto the substrate by the irradiation means in a state where the gap between the mask and the substrate becomes the exposure gap;
A proximity exposure method comprising:

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