JP2006235019A - Exposure device, exposure method, and manufacturing method of panel substrate for display - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce the weight of a chuck and to improve the flatness of the chuck. <P>SOLUTION: A plurality of spokes 13 are mounted on the base plate 12 of a chuck supporting stand 11 radially from the center of the base plate 12. Rims 14 are mounted on the tips of the respective spokes 13 and the adjacent rims 14 are connected to each other to form frames of a polygonal shape. A number of ball pins 15 are disposed atop the spokes 12 and the rims 14. Balls are rotatably mounted on the tips of the respective ball pins 15. A chuck 10 is mounted on the balls of the ball pins 15 and the chuck supporting stand 11 supports the chuck 10 at a number of points. The bottom ends of the ball pins 15 are fastened to the spokes 13 or the rims 14 by screwing. By turning the screws, the ball pins 15 are moved up and down and the heights of the respective points at which the balls of the ball pins 15 support the chuck 10 are adjusted. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an exposure apparatus that performs exposure of a substrate, an exposure method, and a method of manufacturing a display panel substrate using the same in manufacturing a display panel substrate such as a liquid crystal display device.

  The manufacture of TFT (Thin Film Transistor) substrates, color filter substrates, plasma display panel substrates, organic EL (Electroluminescence) display panel substrates, etc. for liquid crystal display devices used as display panels is performed using an exposure apparatus, photolithography. This is performed by forming a pattern on the substrate by a technique.

  As an exposure apparatus, a projection system that projects a photomask (hereinafter referred to as “mask”) pattern onto a substrate using a lens or a mirror, and a small gap (proximity gap) between the mask and the substrate. There is a proximity method in which a mask pattern is provided and transferred. The proximity exposure apparatus is inferior in pattern resolution performance to the projection system, but has a simple configuration of the irradiation optical system and high processing capability, and is suitable for mass production.

  The proximity exposure apparatus includes a chuck that holds the substrate by vacuum suction, and the chuck is mounted on a stage that moves and positions the substrate. The substrate is normally attached to and detached from the chuck by a handling arm such as a robot. However, in order to avoid contact between the mask and the substrate, it is performed at a delivery position away from the exposure position under the mask. After fixing the substrate on the chuck at the delivery position, the stage moves to the exposure position under the mask, and the substrate is positioned at the exposure position.

  Conventionally, the stage is composed of a three-axis stage of X, Y, and θ and a Z-tilt mechanism. The triaxial stage moves and positions the substrate by moving the chuck in the X and Y directions or rotating in the θ direction. The Z-tilt mechanism controls the gap between the mask and the substrate by supporting the chuck at three points, moving each point up and down, and moving and tilting the chuck in the Z direction.

  In recent years, a relatively large substrate has been prepared in order to cope with an increase in screen size and a variety of sizes of display panels. Depending on the size of the display panel, one or more display panels can be formed from one substrate. Manufactures substrates. In this case, in the proximity method, if the entire surface of the substrate is to be exposed at once, a mask having the same size as the substrate is required, which further increases the cost of the expensive mask. In view of this, the mainstream method uses a mask that is relatively smaller than the substrate and exposes the entire surface of the substrate in a plurality of shots while stepping the substrate in the XY directions by a stage.

As a proximity exposure apparatus that performs exposure on a substrate larger than the mask in this way, for example, there are those described in Patent Document 1 and Patent Document 2.
Japanese Patent Laid-Open No. 11-52583 JP 2000-241995 A

  In order to improve exposure accuracy with a proximity exposure apparatus, the substrate must be held flatter during exposure. For this reason, the chuck for holding the substrate is required to have high flatness. In particular, as the substrate becomes larger, the demand for flatness of the chuck becomes stronger.

  On the other hand, in order to reduce the tact time in the proximity exposure apparatus, there is a demand for moving the substrate at high speed between the transfer position for transferring the substrate and the exposure position for exposing the substrate. In order to move the substrate at high speed, it is necessary to reduce the weight of the chuck that holds the substrate. In particular, as the size of the substrate increases or the movement of the substrate increases, the weight reduction of the chuck is strongly desired. It is.

  Since the conventional proximity exposure apparatus supports the chuck at three points by the Z-tilt mechanism, in order to maintain the flatness of the chuck, it is necessary to increase the thickness of the chuck so that the chuck has a certain degree of rigidity. There was a problem that the chuck became heavy.

  Further, in order to improve the exposure accuracy with the proximity exposure apparatus, it is necessary to accurately control the gap between the mask and the substrate. In the conventional proximity exposure apparatus, the gap control is performed by the Z-tilt mechanism of the stage, and the centers of the three points of the Z-tilt mechanism, which is the center position of the gap control, are aligned with the center of the substrate. For this reason, when exposing the entire surface of the substrate in a plurality of shots, there is a problem that the center position of the gap control (the center of the substrate) is shifted from the center of the gap (the center of the mask) and the accuracy of the gap control decreases. It was. In particular, as the substrate size increases and the difference from the mask size increases, the gap between the gap center (mask center) and the gap control center position (substrate center) increases, and the accuracy of the gap control decreases. It becomes remarkable.

  An object of the present invention is to reduce the weight of the chuck and improve the flatness of the chuck. Another object of the present invention is to prevent the accuracy of gap control from being lowered when the entire surface of a substrate is exposed in a plurality of shots. Furthermore, the subject of this invention is manufacturing a high quality display panel board | substrate.

  An exposure apparatus according to the present invention includes a chuck for holding a substrate, a mask holder for holding a mask, chuck support means for supporting the chuck at a number of points, and movement of the substrate held on the chuck. And a stage for positioning, and gap control means for controlling the gap between the substrate held by the chuck and the mask held by the mask holder.

  The exposure method of the present invention also supports movement and positioning of the substrate held by the chuck while supporting the chuck holding the substrate at a number of points, as well as the substrate held by the chuck and the mask held by the mask holder. The gap control is performed.

  Since the chuck is supported at a number of points, it is not necessary to provide the chuck with greater rigidity than when the conventional chuck is supported at three points. Therefore, the thickness of the chuck can be reduced to reduce the weight of the chuck. In addition, the height of each point supporting the chuck can be adjusted to correct the deflection of the chuck and improve the flatness of the chuck.

  Further, in the exposure apparatus of the present invention, the gap control means has a Z-tilt mechanism for moving and tilting the mask holder up and down. In the exposure method of the present invention, the gap between the substrate and the mask is controlled by moving and tilting the mask holder up and down by a Z-tilt mechanism.

  Since the gap between the substrate and the mask is controlled by moving and tilting the mask holder up and down, the center position of the gap control always coincides with the center of the gap (mask center). Therefore, even when the entire surface of the substrate is exposed in a plurality of shots, the accuracy of gap control does not decrease.

  Furthermore, in the exposure apparatus of the present invention, the gap control means has a load support mechanism that supports the load of the mask holder. The exposure method of the present invention supports the load of the mask holder with a load support mechanism provided separately from the Z-tilt mechanism.

  Since the load of the mask holder is supported by a load support mechanism provided separately from the Z-tilt mechanism, the Z-tilt mechanism can move and tilt the mask holder up and down with a small force, and the accuracy of gap control is improved.

  The method for producing a display panel substrate of the present invention is to transfer a mask pattern onto the substrate using any one of the above exposure apparatuses or exposure methods. By using the above exposure apparatus or exposure method, the exposure accuracy is improved when the mask pattern is transferred onto the substrate.

  According to the exposure apparatus and the exposure method of the present invention, the chuck can be reduced in weight and the flatness of the chuck can be improved by supporting the chuck at a number of points.

  Further, by performing the gap control between the substrate and the mask by moving and tilting the mask holder up and down, it is possible to prevent the accuracy of the gap control from being lowered when the entire surface of the substrate is exposed in a plurality of shots.

  Furthermore, by supporting the load of the mask holder with a load support mechanism provided separately from the Z-tilt mechanism, the Z-tilt mechanism can move and tilt the mask holder up and down with a small force, and the accuracy of gap control can be increased. Can be improved.

  According to the method for manufacturing a display panel substrate of the present invention, exposure accuracy can be improved when a mask pattern is transferred onto the substrate. Therefore, a high-quality display panel substrate can be manufactured.

  FIG. 1 is a view showing the arrangement of an exposure apparatus according to an embodiment of the present invention. The exposure apparatus includes a base 3, an X guide 4, an X stage 5, a Y guide 6, a Y stage 7, a θ stage 8, a chuck 10, a chuck support 11, and a mask holder 20. In addition to the above, the exposure apparatus includes an exposure light source, a supply unit that supplies the substrate 1 to the chuck 10, a recovery unit that recovers the substrate 1 from the chuck 10, a temperature control unit that manages the temperature in the apparatus, and the like. However, in this embodiment, portions not directly related to the invention are omitted.

  In FIG. 1, the chuck 10 is in a delivery position for delivering the substrate 1. At the delivery position, the substrate 1 is supplied to the chuck 10 by a supply unit (not shown), and the substrate 1 is recovered from the chuck 10 by a recovery unit (not shown). A mask 2 is held by a mask holder 20 above the exposure position where the substrate 1 is exposed.

  The chuck 10 is mounted on the θ stage 8 via the chuck support 11, and a Y stage 7 and an X stage 5 are provided below the θ stage 8. The X stage 5 moves in the X direction (the horizontal direction in the drawing) along the X guide 4 provided on the base 3. As the X stage 5 moves in the X direction, the substrate 1 held by the chuck 10 moves between the delivery position and the exposure position. In addition, although a linear motor etc. are used as a drive means, illustration is abbreviate | omitted. The Y stage 7 moves in the Y direction (the drawing depth direction) along the Y guide 6 provided on the X stage 5, and the θ stage 8 rotates in the θ direction.

  At the exposure position, the substrate 1 is positioned during exposure by moving the X stage 5 in the X direction, moving the Y stage 7 in the Y direction, and rotating the θ stage 8 in the θ direction. Further, the gap control between the substrate 1 and the mask 2 is performed by the movement and tilting of a Z-tilt mechanism to be described later in the Z direction (vertical direction in the drawing).

  2A is a top view of the chuck support of the exposure apparatus according to the embodiment of the present invention, and FIG. 2B is a side view thereof. The chuck support base 11 includes a base plate 12, spokes 13, a rim 14, and ball pins 15.

  The base plate 12 is mounted on the θ stage 8 indicated by a broken line in FIG. On the base plate 12, a plurality of spokes 13 are attached radially from the center of the base plate 12. A rim 14 is attached to the tip of each spoke 13, and adjacent rims 14 are connected to form a polygonal frame. A large number of ball pins 15 are provided on the upper surfaces of the spokes 13 and the rim 14.

  In the present embodiment, 21 ball pins 15 are provided, but the number and arrangement of the ball pins 15 are appropriately determined according to the size and shape of the chuck 10.

  A ball is rotatably attached to the upper end of each ball pin 15. A chuck 10 indicated by a broken line in FIG. 2B is mounted on the ball pin 15, and the chuck support 11 supports the chuck 10 at a number of points. The lower end of each ball pin 15 is screwed to the spoke 13 or the rim 14, and the ball pin 15 moves up and down by turning the screw, and the ball pin 15 has a height at each point where the ball 10 supports the chuck 10. Is adjusted.

  According to the present embodiment, since the chuck 10 is supported at a number of points, it is not necessary to give the chuck 10 greater rigidity than when the conventional chuck is supported at three points. Therefore, the thickness of the chuck 10 can be reduced and the chuck 10 can be reduced in weight. Further, the height of each point supporting the chuck 10 can be adjusted to correct the deflection of the chuck, and the flatness of the chuck 10 can be improved.

  In addition, according to the present embodiment, the chuck support base 11 is configured by the base plate 12, the spokes 13, and the rim 14, so that the chuck support base 11 can be lightened while ensuring the strength of the chuck support base 11. it can. However, the configuration of the chuck support base 11 is not limited to this.

  The chuck 10 includes a suction mechanism (not shown) for vacuum suction of the substrate, and is made of aluminum. In several places on the back surface of the chuck 10, V-shaped grooves that abut the balls of the ball pins 15 are provided. When the balls of the ball pins 15 fit into these grooves, the chuck mounted on the chuck support 11 is mounted. 10 positioning is performed.

  By using aluminum as the material of the chuck 10, it is possible to contribute to weight reduction of the chuck 10 and to obtain a sufficient heat dissipation effect during exposure. Furthermore, the reflectance can be lowered by covering the surface of the chuck 10 with an aluminum oxide film.

  FIG. 3 is a top view of the mask holder of the exposure apparatus according to the embodiment of the present invention. FIG. 4 is a side view of the mask holder of the exposure apparatus according to the embodiment of the present invention. 4 shows a state in which the mask holder support member 30b is removed as viewed in the direction of the arrow in FIG.

  As shown in FIG. 3, an opening for transmitting exposure light is provided at the center of the mask holder 20. As shown in FIG. 4, the mask 2 is attached to the lower surface of the mask holder 20 so as to cover the opening. The mask holder 20 holds the outer peripheral portion of the mask 2 by vacuum suction.

  As shown in FIG. 3, a plurality of support arms 21 are attached to the four sides of the mask holder 20. Around the four sides of the mask holder 20, mask holder support members 30a, 30b, 30c, and 30d are provided. Support plates 31 are attached to the mask holder support members 30a, 30b, 30c, and 30d at positions that overlap the support arms 21 when viewed from above, while changing the height of the support arms 21.

  As shown in FIG. 4, a load support mechanism 41 is provided between the support arm 21 and the support plate 31. The load support mechanism 41 is composed of an air cushion, for example, and supports the load of the mask holder 20 by air pressure.

  In the present embodiment, eight load support mechanisms 41 are provided, but the number and arrangement of the load support mechanisms 41 are appropriately determined according to the weight and shape of the mask holder 20.

  As shown in FIG. 3, tilt arms 22 are attached to three locations on the four sides of the mask holder 20. A Z-tilt mechanism 42 is attached to the mask holder support members 30a and 30b at a position overlapping the tilt arm 22 when viewed from above.

  As shown in FIG. 4, the Z-tilt mechanism 42 is connected to the tilt arm 22. Each Z-tilt mechanism 42 includes, for example, a motor and a ball screw driven by the motor, and moves and tilts the mask holder 20 up and down by moving each tilting arm 22 up and down with the ball screw. Gap control between the substrate held by the chuck and the mask 2 held by the mask holder 20 is performed.

  According to the present embodiment, by moving and tilting the mask holder 20 up and down to control the gap between the substrate and the mask 2, the center position of the gap control always coincides with the center of the gap (the center of the mask 2). To do. Therefore, when the entire surface of the substrate is exposed by being divided into a plurality of shots, it is possible to prevent the accuracy of gap control from being lowered.

  Furthermore, according to the present embodiment, by supporting the load of the mask holder 20 with the load support mechanism 41 provided separately from the Z-tilt mechanism 42, the Z-tilt mechanism 42 moves the mask holder 20 up and down with a small force. It can be moved and tilted, and the accuracy of gap control can be improved.

  By using the exposure apparatus or exposure method of the present invention to transfer the mask pattern onto the substrate, the exposure accuracy can be improved. Therefore, a high-quality display panel substrate can be manufactured.

It is a figure which shows the structure of the exposure apparatus by one embodiment of this invention. 2A is a top view of the chuck support of the exposure apparatus according to the embodiment of the present invention, and FIG. 2B is a side view thereof. It is a top view of the mask holder of the exposure apparatus by one Embodiment of this invention. It is a side view of the mask holder of the exposure apparatus by one Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Substrate 2 Mask 3 Base 4 X guide 5 X stage 6 Y guide 7 Y stage 8 θ stage 10 Chuck 11 Chuck support base 12 Base plate 13 Spoke 14 Rim 15 Ball pin 20 Mask holder 21 Support arm 22 Tilt arm 30a, 30b, 30c, 30d Mask holder support member 31 Support plate 41 Load support mechanism 42 Z-tilt mechanism

Claims (8)

A chuck for holding a substrate;
A mask holder for holding a photomask;
Chuck support means for supporting the chuck at a number of points;
A stage on which the chuck support means is mounted and which moves and positions the substrate held by the chuck;
An exposure apparatus comprising: a gap control unit that controls a gap between the substrate held by the chuck and the photomask held by the mask holder.   The exposure apparatus according to claim 1, wherein the gap control unit has a Z-tilt mechanism that moves and tilts the mask holder up and down.   The exposure apparatus according to claim 2, wherein the gap control unit includes a load support mechanism that supports a load of the mask holder.   While supporting the chuck holding the substrate at many points, the movement and positioning of the substrate held by the chuck and the gap control between the substrate held by the chuck and the photomask held by the mask holder are performed. Exposure method.   5. The exposure method according to claim 4, wherein the gap between the substrate and the photomask is controlled by moving and tilting the mask holder up and down by a Z-tilt mechanism.   6. The exposure method according to claim 5, wherein the load of the mask holder is supported by a load support mechanism provided separately from the Z-tilt mechanism.   A method for manufacturing a display panel substrate, comprising: transferring a photomask pattern onto a substrate using the exposure apparatus according to claim 1.   A method for manufacturing a display panel substrate, wherein a photomask pattern is transferred onto a substrate using the exposure method according to claim 4.

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