JP2007328008A - Exposure device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an exposure device for correcting a deflection of a substrate while suppressing a fluctuation of a distance between a mask and the substrate. <P>SOLUTION: Since a movable part 126B to a fixed part 126A is driven by first screws 133 and second screws 134 in a direction (horizontal direction) parallel to the face of the mask M, the fluctuation of the movable part 126B to the fixed part 126A in a vertical direction is suppressed. Thereby, since the deflection of the mask M is corrected while the fluctuation of the distance between the mask M and the substrate W is suppressed, readjustment of a camera observing an alignment mark of the mask and an aperture hiding a pattern is facilitated or is not needed. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an exposure apparatus suitable for proximity exposure transfer of a mask pattern of a mask onto a substrate of a large flat panel display such as a liquid crystal display or a plasma display by a divided sequential exposure method.

  Large flat panel displays such as liquid crystal displays and plasma displays used in large thin televisions and the like are manufactured by proximity exposure transfer of a mask pattern onto a substrate by a divided sequential exposure method. As a conventional sequential sequential exposure apparatus of this type, for example, a mask smaller than the substrate as the material to be exposed is used, the mask is held on the mask stage and the substrate is held on the work stage, and both are placed close to each other. In this state, the work stage is moved stepwise with respect to the mask, and the substrate is exposed to light for pattern exposure from the mask side at each step, thereby exposing a plurality of mask patterns drawn on the mask onto the substrate. There is known one in which a plurality of displays and the like are created on a single substrate by transfer.

  By the way, one problem in the case of proximity exposure transfer is how to accurately transfer the mask pattern. In other words, it is difficult to irradiate the mask with the light flux from the light source in a completely parallel state. Therefore, if there is a distance between the mask and the substrate at the time of exposure, the resolution decreases and the pattern is formed by obliquely incident light. Cannot be transferred with high accuracy. Therefore, there is a demand to make the mask and the substrate as close as possible without contacting each other. However, since the mask is full-scale, it has a length of, for example, 1 m or more, and its thickness is usually 15 mm or less, and is characterized by being easily deflected by its own weight when holding the periphery of the mask. Therefore, it can be said that the deflection of the mask needs to be corrected in order to bring the mask and the substrate close to each other at a certain distance.

On the other hand, in the exposure apparatuses shown in Patent Documents 1 and 2, a sealed space is defined above the mask, and the deflection of the mask is corrected by decompressing the inside.
JP 2004-61577 A JP 2003-131388 A

  However, Patent Documents 1 and 2 have no description about correction when the substrate itself is distorted. Specifically, when distortion occurs in the substrate holding portion that holds the substrate, the substrate itself is deformed accordingly. Regardless of this, only correcting the deflection of the mask causes the mask and the substrate to be at a certain distance. Cannot be close. In particular, in recent years, the size of the substrate holding portion has increased, and it is difficult to form a completely flat holding portion.

  In contrast, in the Japanese Patent Application No. 2004-373608, the present applicant supports the mask at the front end portion of the mask holder, arranges an angle setting portion at the rear end portion of the mask, and further includes a front end portion and a rear end portion. A support portion supported in a tiltable manner by using a roller and a V block is provided between the front end portion of the mask holder by utilizing the fact that the mask holder is tilted around the support point by pressing the mask holder with the angle setting portion. A mechanism has been proposed in which the mask held in is inclined to thereby correct the deflection of the mask.

  However, according to the mechanism of the prior application, the front end portion of the mask holder is displaced at the same time as being angled by pressing the mask holder with the angle setting portion, so that the distance between the mask and the substrate is relatively large. As a result, there is a problem that it is necessary to readjust the camera for observing the alignment mark of the mask and the aperture for hiding the pattern.

  Accordingly, an object of the present invention is to provide an exposure apparatus capable of correcting the deflection of the substrate while suppressing the variation in the distance between the mask and the substrate.

In order to achieve the above object, an exposure apparatus of the present invention has a mask holding unit that holds a mask on which a pattern is formed and a substrate holding unit that holds a substrate, and irradiates the mask with light from a light source. In an exposure apparatus that exposes the substrate to the pattern,
The mask holding part includes a movable part attached to the mask, a fixed part fixed to a frame, a hinge part that connects the movable part and the fixed part to be tiltable, and the movable part with respect to the fixed part. And driving means for driving in a direction parallel to the surface of the mask.

  According to the present invention, the mask holding part includes a movable part attached to the mask, a fixed part fixed to the frame, a hinge part that connects the movable part and the fixed part so as to be tiltable, and the fixed part. Drive means for driving the movable part in a direction parallel to the surface of the mask, so that the drive means drives the movable part in a direction parallel to the surface of the mask by the drive means. In this case, the displacement of the movable part relative to the fixed part in the direction intersecting the driving direction is suppressed, thereby correcting the deflection of the mask while suppressing the variation in the distance between the mask and the substrate. be able to.

  The hinge part is preferably a leaf spring.

  The driving means preferably includes a screw.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a side view of the exposure apparatus according to the present embodiment. In FIG. 1, the exposure apparatus 100 according to this embodiment includes a base 112, a substrate stage 114, and a mask stage 122. The substrate stage (substrate holding unit) 114 is provided above the base 112. Between the base 112 and the substrate stage 114, a substrate stage elevating mechanism 116 that moves the substrate stage 114 up and down, and the substrate stage elevating and lowering. A substrate stage tilt mechanism 118 that swings and drives the substrate stage 114 via the mechanism 116, a substrate stage tilt mechanism 118, and a substrate stage lifting mechanism 116 are used to move the substrate stage 114 in the X-axis direction and Y-axis direction (with respect to the paper surface). A substrate stage feed mechanism 120 that feeds and drives in a vertical direction) is provided.

  The mask stage 122 is supported above the substrate stage 114 by a plurality of columns 124 erected on the upper surface of the base 112, and a plate-like mask holder (mask holding portion) 126 is provided on the lower surface of the mask stage 122. It is attached via support portions 128 and 130 for adjusting the horizontal level. The mask stage 122 has a rectangular opening window 122a at the center, and the exposure light emitted from the light source device (not shown) is attracted and held by the mask holder 126 to the opening window 122a. It comes to be irradiated through.

  The mask holder 126 has an opening window 126 a for applying light that has passed through the opening window 122 a of the mask stage 122 to the mask M. The opening window 126 a is formed at the center of the mask holder 126, and a plurality of suction nozzles (not shown) for mask suction are opened on the lower surface of the mask holder 126.

  FIG. 2 is an enlarged view of a portion indicated by an arrow II in the configuration of FIG. In FIG. 2, a thin plate-like mask holder 126 is composed of an outer peripheral fixed portion 126A and an inner peripheral movable portion 126B. By screwing the tips of the bolts 129 and 129 penetrating through the fixed portion 126A and the cylindrical support portions 128 and 130 into the mask stage 122, the fixed portion 126A is connected to the mask stage via the cylindrical support portions 128 and 130. It is attached to 122 (also referred to as a frame).

  The movable portion 126B holds the periphery of the mask M by suction on its lower surface. One end of the spring plate 127 constituting the hinge portion is screwed to the upper surface of the fixed portion 126A, and the other end is screwed to the upper surface of the movable portion 126B, thereby connecting the fixed portion 126A and the movable portion 126B. It is connected.

  A first protrusion 131 is formed on the lower surface of the fixing portion 126A. A first screw hole 131a having an axis in the horizontal direction (direction parallel to the surface of the mask M in an ideal holding state) is formed in the first protrusion 131. On the other hand, a second protrusion 132 is formed on the lower surface of the movable portion 126B adjacent to the first protrusion 131. A second screw hole 132a is formed in the second protrusion 132 in the same direction as the first screw hole 131a.

  A hollow cylindrical first screw 133 is screwed into the first screw hole 131 a, and the tip of the first screw hole 131 a faces the end surface of the second protrusion 132. On the other hand, the tip of the second screw 134 penetrating through the first screw 133 is engaged with the second screw hole 132a. The second screw 134 is connected to the first screw 133 so that it can only rotate and cannot move in the axial direction. The first screw 133 and the second screw 134 constitute drive means.

  Next, a comparative example will be described. FIG. 3 is a view similar to FIG. 2 in the comparative example. Here, on the peripheral side of the mask holder 126 ′, which is a single plate, an external force applying mechanism 130 ′ for applying a downward external force to the mask stage 122 is provided on the upper surface of the mask holder 126 ′. As shown in the drawing, the external force applying mechanism 130 ′ includes a fixed taper block 132 ′ having an inclined surface 132a ′ inclined from the outside to the inside of the mask holder 126 ′, and a fixed taper block 132 ′. A movable side taper block 134 ′ having an inclined surface 134a ′ that slidably contacts the inclined surface 132a ′, and a movable side taper block that moves the movable side taper block 134 ′ toward and away from the support portion 130 ′. The fixed side taper block 132 ′ is configured to include a feed screw 136 ′ as a feed means. It is fixed to the upper surface of 126 '. The feed screw 136 'is held by a bracket 138' provided on the fixed taper block 132 '. The external force applying mechanism 130 'is provided at the four corners of the mask holder 126'.

  Further, a support portion 128 ′ is provided on the mask M side with respect to the external force applying mechanism 130 ′. The support portion 128 ′ includes a V block 128a ′ attached to the lower surface of the mask stage 122, a V block 128b ′ attached to the upper surface of the mask holder 126 ′ opposite thereto, and a cylindrical member disposed therebetween. 128c ′.

  In the configuration of the comparative example, when the feed screw 136 ′ of the external force applying mechanism 130 ′ is operated to move the movable side taper block 134 ′ to the right side in the figure, the external force applied downward from the external force applying mechanism 130 ′ to the mask holder 126 ′. F is given. When the external force F is applied from the external force applying mechanism 130 ′ to the mask holder 126 ′, the mask holder 126 ′ is inclined with the support portion 128 ′ as a fulcrum. As a result, as indicated by a two-dot chain line, the end of the mask M attracted and held by the mask holder 126 ′ rises and tilts, so that the deflection due to the weight of the mask M can be corrected. However, in the case of the comparative example, since the mask holder 126 ′ is tilted with the support portion 128 ′ as a fulcrum, the rising amount of the end portion of the mask M increases in proportion to the distance between the support portion 128 ′ and the end portion of the mask M. Therefore, the distance between the mask M and the substrate W (FIG. 1) may change greatly.

  The operation of this embodiment will be described. In FIG. 2, the first screw 133 is for determining the inclination of the movable portion 126 </ b> B. When the first screw 133 is a right-hand screw, the end surface of the second protrusion 132 is rotated to the right and tightened. To increase the distance L between the first protrusion 131 and the second protrusion 132, and the spring plate 127 bends, so that the movable portion 126B moves upward with respect to the fixed portion 126A as shown by a two-dot chain line. It becomes inclined. As a result, the end portion of the mask M attracted and held by the movable portion 126B is also tilted, so that the deflection of the mask M due to its own weight can be corrected.

  On the other hand, if the first screw 133 is rotated counterclockwise and loosened, the movable portion 126B is lowered. Here, the second screw 134 is a lock screw for preventing the rotation of the first screw 133. If the second screw 134 does not rotate, the angle of the movable portion 126B does not change. .

  It should be noted that the first screw 133 and the second screw 134 can be automatically rotated by an actuator rather than manually by the operator. This will be described more specifically. For example, in FIG. 4, the substrate W is held on the substrate stage 114, and the mask M is held on the mask stage 122 via the mask holder 126. However, it is difficult to support the substrate W in a completely flat state. Therefore, the substrate W is locally subject to minute waviness and the like, and may vary with respect to the reference thickness Δ. Such variation hinders highly accurate exposure.

  On the other hand, according to the present embodiment, the first screw 133 and the second screw 134 as driving means for deforming the mask M according to the distortion of the substrate W can be driven by the actuator ACT. Referring to FIG. 5, for example, when sensor S detects a distortion (such as a variation in the height of the upper surface) of substrate W, control device CPU receives the signal and transmits a drive signal corresponding to the signal to actuator ACT. Thereby, according to the distortion of the substrate W, the actuator ACT rotates the first screw 133 or the second screw 134 to deform the mask M in the above-described manner, so that the mask M and the substrate W Since the mask M is irradiated with light from the light source, the pattern formed thereon can be exposed to the substrate W with high accuracy. For example, the distortion of the substrate W may be measured for each position of the mask M, and the mask M may be deformed into a stored shape when moved to that position.

  According to the present embodiment, the first screw 133 and the second screw 134 drive the movable portion 126B with respect to the fixed portion 126A in a direction (horizontal direction) parallel to the surface of the mask M. Since the displacement of the movable portion 126B with respect to the fixed portion 126A at this time is suppressed, thereby suppressing the variation in the distance between the mask M and the substrate W, the deflection of the mask M can be corrected, so that the alignment mark on the mask is observed. Re-adjustment of the camera and the aperture that hides the pattern becomes easy or unnecessary.

  The present invention has been described above with reference to the embodiments. However, the present invention should not be construed as being limited to the above-described embodiments, and can be modified or improved as appropriate.

It is a side view of the exposure apparatus concerning this Embodiment. It is a figure which expands and shows the site | part shown by the arrow II of the structure of FIG. It is a figure similar to FIG. 2 concerning a comparative example. 6 is a diagram for explaining a method of correcting the deflection of the mask M in accordance with the deflection of the substrate W. FIG. 6 is a diagram for explaining a method of correcting the deflection of the mask M in accordance with the deflection of the substrate W. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Exposure apparatus 112 Base 114 Substrate stage 116 Substrate stage raising / lowering mechanism 118 Substrate stage tilt mechanism 120 Substrate stage feed mechanism 122 Mask stage 122a Open window 124 Post 126 Mask holder 126A Fixed part 126B Movable part 126a Open window 127 Spring plates 128 and 130 Support Parts 129, 129 Bolt 131 First protrusion 131a First screw hole 132 Second protrusion 132a Second screw hole ACT Actuator CPU Controller M Mask S Sensor W Substrate

Claims (3)

In an exposure apparatus that has a mask holding unit that holds a mask on which a pattern is formed, and a substrate holding unit that holds a substrate, and irradiates the mask with light from a light source, thereby exposing the pattern to the substrate.
The mask holding part includes a movable part attached to the mask, a fixed part fixed to a frame, a hinge part that connects the movable part and the fixed part to be tiltable, and the movable part with respect to the fixed part. An exposure apparatus comprising: a driving unit that drives the lens in a direction parallel to the surface of the mask.   The exposure apparatus according to claim 1, wherein the hinge portion is a leaf spring. The exposure apparatus according to claim 1, wherein the driving unit includes a screw.

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