JP2013171088A - Proximity exposure apparatus, method for forming exposure light of proximity exposure apparatus, and method for manufacturing display panel substrate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form high luminance exposure light by achieving easy installation of semiconductor light-emitting elements and efficiently utilizing light of the semiconductor light-emitting element.SOLUTION: A proximity exposure apparatus has a base substrate 41 and a fly-eye lens 45. The base substrate 41 and the fly-eye lens 45 are arranged so that a distance from a center of a semiconductor light-emitting element group mounted on the base substrate 41 to a center of a concave mirror 50 and a distance from the center of the concave mirror 50 to a center of an incidence plane of the fly-eye lens 45 are equal to a focal distance of the concave mirror 50, and so that a center location of the semiconductor light-emitting element group mounted on the base substrate 41 and a center location of the incidence plane of the fly-eye lens 45 are symmetrical about a normal line passing through a focal point of the concave mirror 50. A plurality of semiconductor light-emitting elements 42 and a plurality of magnifying lenses 43 are arranged so that an optical axis of light that is generated by each semiconductor light-emitting element 42, magnified by the corresponding magnifying lens 43 and reflected on the concave mirror 50 is made incident to the fly-eye lens 45 at an angle equal to or less than a predetermined value that does not deviate from the irradiation surface of the fly-eye lens 45.

Description

  The present invention relates to a proximity exposure apparatus and a proximity exposure apparatus using a plurality of semiconductor light emitting elements as a light source for generating exposure light and using a fly-eye lens as an optical integrator in manufacturing a display panel substrate such as a liquid crystal display device. The present invention relates to a method for forming exposure light and a method for manufacturing a display panel substrate using them.

  Manufacturing of TFT (Thin Film Transistor) substrates, color filter substrates, plasma display panel substrates, organic EL (Electroluminescence) display panel substrates, and the like of liquid crystal display devices used as display panels is performed using photolithography using an exposure apparatus. This is performed by forming a pattern on the substrate by a technique. As an exposure apparatus, a projection method in which a mask pattern is projected onto a substrate using a lens or a mirror, and a minute gap (proximity gap) is provided between the mask and the substrate to transfer the mask pattern to the substrate. There is a proximity method. The proximity method is inferior in pattern resolution performance to the projection method, but the configuration of the irradiation optical system is simple, the processing capability is high, and it is suitable for mass production.

  Conventionally, a lamp in which high pressure gas is enclosed in a bulb, such as a mercury lamp, a halogen lamp, or a xenon lamp, has been used as a light source for generating exposure light of a proximity exposure apparatus. These lamps have a short life and must be replaced after a predetermined usage time. For example, if the lamp has a lifetime of 750 hours and it is lit continuously, it needs to be replaced about once a month. When the lamp is replaced, the exposure process is interrupted, resulting in a decrease in productivity.

  On the other hand, Patent Document 1 discloses a technique using a semiconductor light emitting element such as a light emitting diode or a laser diode as a light source of exposure light in a proximity exposure apparatus. Semiconductor light-emitting elements such as light-emitting diodes and laser diodes have a lifetime of several thousand hours, which is longer than that of lamps, and exposure processing is rarely interrupted.

  When a plurality of semiconductor light emitting elements are used as a light source for generating exposure light, a fly-eye lens is used as an optical integrator as described in Patent Document 1. The fly-eye lens is a lens array in which a plurality of single lenses are arranged vertically and horizontally. FIG. 12 is a diagram for explaining the operation of the fly-eye lens. The light generated from the plurality of semiconductor light emitting elements 42 is magnified by the magnifying lens 43 and irradiated to the fly-eye lens 45. The fly-eye lens 45 projects and superimposes the light expanded by the plurality of magnifying lenses 43 on the same irradiation surface, and uniformizes the illuminance distribution. At this time, the light incident on the fly-eye lens 45 deviates from the irradiation surface of the fly-eye lens 45 when the incident angle β is larger than a predetermined angle.

  In recent years, as the size of the substrate is increased with the increase in the screen size of the display panel, a light source with higher illuminance has been required for the exposure light source. In proximity exposure equipment mainly used for exposure of large substrates, when using multiple semiconductor light emitting elements as a light source that generates exposure light, the output of the semiconductor light emitting elements is much smaller than conventional lamps, Several hundred to several thousand semiconductor light emitting elements must be used side by side. In that case, a part of the light generated from the outer semiconductor light emitting element and magnified by the magnifying lens has a larger incident angle to the fly-eye lens, and deviates from the irradiation surface of the fly-eye lens to form exposure light. There was a problem that it was not used.

  In the technique described in Patent Document 1, a reflection member is provided so as to surround an optical path from a plurality of magnifying lenses to a fly-eye lens, and light that is not directly irradiated to the fly-eye lens of light generated from a semiconductor light emitting element is reflected by the reflection member. Reflecting and entering the fly-eye lens within a predetermined angle that does not deviate from the irradiation surface of the fly-eye lens, the light from each semiconductor light-emitting element is efficiently used to form exposure light with high illuminance. .

JP 2011-17770 A

  When multiple semiconductor light emitting elements are used as the light source for generating exposure light and a fly-eye lens is used as an optical integrator, most of the light generated from each semiconductor light-emitting element does not deviate from the irradiation surface of the fly-eye lens. In order to use the light generated from each semiconductor light emitting element efficiently, the optical axis of the light generated from each semiconductor light emitting element is directed to the center of the incident surface of the fly eye lens. There is a need. Therefore, conventionally, the surface of the base substrate on which each semiconductor light emitting element is mounted is formed into a spherical surface, and each semiconductor light emitting element is arranged on the spherical surface. However, adjusting the mounting angle of each semiconductor light emitting element arranged on the spherical surface and accurately aligning the optical axis of the light generated from each semiconductor light emitting element with the center of the entrance surface of the fly-eye lens takes time and effort. Adjustment of the mounting angle of hundreds to thousands of semiconductor light emitting elements requires a great deal of labor and time.

  On the other hand, as described in Patent Document 1, when a base substrate is configured by combining a plurality of flat substrates having different mounting angles, each semiconductor light emitting element can be easily mounted on the base substrate, but is mounted on each substrate. It is necessary to adjust the mounting angle of each substrate so that the optical axis of the light generated from each semiconductor light emitting element is accurately directed to the center of the entrance surface of the fly-eye lens. Moreover, when using the reflecting member as in Patent Document 1, the length of the reflecting member reaches several meters, and it is difficult to install such a large reflecting member without distortion and to adjust the mounting angle.

  It is an object of the present invention to facilitate installation of each semiconductor light emitting element and to efficiently use light from each semiconductor light emitting element when forming exposure light by superimposing light generated from a plurality of semiconductor light emitting elements with a fly-eye lens. It is used to form exposure light with high illuminance. Another object of the present invention is to improve the productivity of a display panel substrate.

  The proximity exposure apparatus of the present invention is provided corresponding to each semiconductor light emitting element, a plurality of semiconductor light emitting elements that generate light forming exposure light, a base substrate on which the plurality of semiconductor light emitting elements are mounted, and each semiconductor light emitting element. A proximity exposure apparatus that includes a plurality of magnifying lenses that magnify light generated from a light emitting element and a fly-eye lens, and that forms exposure light by superimposing light magnified by a plurality of magnifying lenses with a fly-eye lens. A concave mirror that is provided in the optical path from the plurality of magnifying lenses to the fly-eye lens, has a parabolic mirror surface, reflects the light magnified by the plurality of magnifying lenses and irradiates the fly-eye lens, The base substrate is configured to be flat, and a plurality of semiconductor light emitting elements are mounted on the same plane, and the base substrate and the fly-eye lens are semiconductors mounted on the base substrate. The distance from the center of the optical element group to the center of the concave mirror and the distance from the center of the concave mirror to the center of the entrance surface of the fly-eye lens are equal to the focal length of the concave mirror, and the semiconductor light emitting element group mounted on the base substrate The center position and the center position of the entrance surface of the fly-eye lens are arranged so as to be symmetric with respect to the normal passing through the focal point of the concave mirror, and the plurality of semiconductor light emitting elements and the plurality of magnifying lenses are separated from each semiconductor light emitting element. The optical axis of the light generated and magnified by the corresponding magnifying lens and reflected by the concave mirror is arranged so that it enters the fly-eye lens within a predetermined angle that does not deviate from the irradiation surface of the fly-eye lens. .

  Further, the exposure light forming method of the proximity exposure apparatus of the present invention mounts a plurality of semiconductor light emitting elements on a base substrate, generates light for forming exposure light from each semiconductor light emitting element, and corresponds to each semiconductor light emitting element. Proximity exposure in which a plurality of magnifying lenses are provided, the light generated from each semiconductor light emitting element is magnified by the corresponding magnifying lens, and the light magnified by the plurality of magnifying lenses is superimposed on the fly-eye lens to form exposure light An exposure light forming method for an apparatus having a paraboloidal mirror surface in an optical path from a plurality of magnifying lenses to a fly-eye lens, and reflecting light magnified by the plurality of magnifying lenses to a fly-eye lens Provide a concave mirror to irradiate, make the base substrate flat, mount multiple semiconductor light emitting devices on the same plane, and mount the base substrate and fly-eye lens on the base substrate Semiconductor light emitting element group mounted on the base substrate, and the distance from the center of the semiconductor light emitting element group to the center of the concave mirror and the distance from the center of the concave mirror to the center of the entrance surface of the fly-eye lens are equal to the focal length of the concave mirror The center position of the fly-eye lens and the center position of the entrance surface of the fly-eye lens are arranged symmetrically with respect to the normal passing through the focal point of the concave mirror, and a plurality of semiconductor light-emitting elements and a plurality of magnifying lenses are arranged in each semiconductor light-emitting element. The optical axis of the light generated from the lens and magnified by the corresponding magnifying lens and reflected by the concave mirror is arranged so as to be incident on the fly-eye lens within a predetermined angle that does not deviate from the irradiation surface of the fly-eye lens. Light generated from the semiconductor light emitting element and enlarged by a plurality of magnifying lenses is reflected by a concave mirror and applied to a fly-eye lens.

  A concave mirror is provided in the optical path from the plurality of magnifying lenses to the fly-eye lens, which has a parabolic mirror surface and reflects the light magnified by the plurality of magnifying lenses to irradiate the fly-eye lens. When the mirror surface of the concave mirror is a paraboloid, all the light generated from the focal point of the concave mirror becomes parallel when reflected by the mirror surface of the concave mirror. Further, light incident in parallel with the normal passing through the focal point of the concave mirror is all collected at the focal point when reflected by the mirror surface of the concave mirror. When light incident obliquely at the same angle with respect to the normal passing through the focal point of the concave mirror is reflected by the mirror surface of the concave mirror, it gathers at one point that differs depending on the incident angle, and the distance from the center of the concave mirror at each point is the focal point. Same as distance.

  Since the base substrate is configured to be flat and the plurality of semiconductor light emitting elements are mounted on the same plane, the plurality of semiconductor light emitting elements can be easily installed on the same plane at the same mounting angle. The distance from the center of the semiconductor light-emitting element group mounted on the base substrate to the center of the concave mirror and the distance from the center of the concave mirror to the center of the entrance surface of the fly-eye lens are the focal length of the concave mirror. Each semiconductor is arranged so that the center position of the semiconductor light emitting element group mounted on the base substrate and the center position of the incident surface of the fly-eye lens are symmetrical with respect to the normal passing through the focal point of the concave mirror. The point where the optical axes of the incident light from the light emitting element to the concave mirror gather is located at the center of the incident surface of the fly-eye lens. Therefore, the optical axis of light generated from each semiconductor light emitting element installed at the same mounting angle on the same plane of the base substrate and incident on the concave mirror obliquely at the same angle with respect to the normal passing through the focal point of the concave mirror is It reflects off the paraboloid of the concave mirror and goes all the way to the center of the entrance surface of the fly-eye lens. The incident angle of each optical axis is within a predetermined angle that does not deviate from the irradiation surface of the fly-eye lens due to the arrangement of a plurality of semiconductor light emitting elements and a plurality of magnifying lenses. Most of the light that is magnified by the magnifying lens and reflected by the concave mirror enters the fly-eye lens within a predetermined angle that does not deviate from the irradiation surface of the fly-eye lens, and is used to form exposure light. Therefore, when the exposure light is formed by superimposing the light generated from a plurality of semiconductor light emitting elements with a fly-eye lens, it is easy to install each semiconductor light emitting element, and the light of each semiconductor light emitting element is used efficiently. The exposure light with high illuminance is formed.

  Further, in the proximity exposure apparatus of the present invention, each magnifying lens expands the light generated from each semiconductor light emitting element and irradiates the concave mirror so that the light reflected by the concave mirror becomes a substantially parallel light beam. It is. In addition, the exposure light forming method of the proximity exposure apparatus of the present invention enlarges the light generated from each semiconductor light emitting element by each magnifying lens so that the light reflected by the concave mirror becomes a substantially parallel light bundle. Irradiates the concave mirror. By appropriately setting the magnification of the magnifying lens, the light reflected by the concave mirror becomes a nearly parallel light bundle, so almost all of the light reflected by the concave mirror is within a predetermined angle that does not deviate from the irradiation surface of the fly-eye lens. Then, the light enters the fly-eye lens and is used to form exposure light. Therefore, the light of each semiconductor light emitting element is used more efficiently, and exposure light with higher illuminance is formed.

  Furthermore, in the proximity exposure apparatus of the present invention, the base substrate is configured by combining a plurality of flat substrates, and a plurality of magnifying lenses are configured for each of the substrates. In the exposure light forming method of the proximity exposure apparatus of the present invention, a plurality of flat substrates are combined to form a base substrate, and a plurality of magnifying lenses are formed for each substrate. Depending on the optical characteristics of the fly-eye lens and concave mirror, the base substrate can be sized appropriately to achieve the required arrangement of semiconductor light emitting elements, and the optical axis of each magnifying lens can be set for each substrate. It can be adjusted easily.

  Furthermore, in the proximity exposure apparatus of the present invention, each semiconductor light emitting element is arranged at the position of each vertex of a plurality of equilateral triangles arranged adjacent to each other without a gap, and each magnifying lens has a cross section perpendicular to the optical axis. They are square and are arranged adjacent to each other with no gaps. Also, in the exposure light forming method of the proximity exposure apparatus of the present invention, each semiconductor light emitting element is arranged at each vertex position of a plurality of equilateral triangles arranged adjacent to each other without a gap, and perpendicular to the optical axis of each magnifying lens. The cross section is a regular hexagon, and the magnifying lenses are arranged adjacent to each other without a gap. A plurality of semiconductor light emitting elements and a plurality of magnifying lenses are evenly arranged with high density, and the entire light source becomes small.

  The method for producing a display panel substrate of the present invention exposes the substrate using any one of the above-described proximity exposure apparatuses, or forms using the exposure light forming method of any one of the above-described proximity exposure apparatuses. The substrate is exposed by irradiating the substrate with the exposed exposure light through a mask. By using the above-described proximity exposure apparatus or the exposure light forming method of the proximity exposure apparatus, the illuminance of the exposure light is increased, the exposure time is shortened, and the life of the exposure light source is increased. Substrate productivity is improved.

  According to the proximity exposure apparatus and the exposure light forming method of the proximity exposure apparatus of the present invention, when forming exposure light by superimposing light generated from a plurality of semiconductor light emitting elements with a fly-eye lens, It is easy to install, and the light from each semiconductor light-emitting element can be used efficiently to form exposure light with high illuminance.

  Furthermore, according to the proximity exposure apparatus and the exposure light forming method of the proximity exposure apparatus of the present invention, each of the semiconductor light-emitting elements is configured so that the light reflected by the concave mirror becomes a substantially parallel light beam by each magnifying lens. By expanding the generated light and irradiating the concave mirror, it is possible to use the light of each semiconductor light emitting element more efficiently and form exposure light with higher illuminance.

  Furthermore, according to the proximity exposure apparatus and the exposure light forming method of the proximity exposure apparatus of the present invention, a plurality of flat substrates are combined to form a base substrate, and a plurality of magnifying lenses are configured for each substrate. According to the optical characteristics of the fly-eye lens and the concave mirror, the size of the base substrate can be appropriately sized to realize the arrangement of the necessary semiconductor light emitting element groups, and the optical axis of each magnifying lens can be set for each substrate. Can be adjusted easily.

  Further, according to the proximity exposure apparatus and the exposure light forming method of the proximity exposure apparatus of the present invention, each semiconductor light emitting element is arranged at the position of each vertex of a plurality of equilateral triangles arranged adjacent to each other without gaps, By making the cross section perpendicular to the optical axis of the magnifying lens a regular hexagon and arranging each magnifying lens adjacent to each other without a gap, a plurality of semiconductor light emitting elements and a plurality of magnifying lenses are arranged uniformly at high density, The entire light source can be reduced in size.

  According to the method for manufacturing a display panel substrate of the present invention, the illuminance of the exposure light is increased, the exposure time is shortened, and the life of the light source of the exposure light is increased, thereby improving the productivity of the display panel substrate. be able to.

It is a figure which shows schematic structure of the proximity exposure apparatus by one embodiment of this invention. It is a figure which shows the light source unit of the proximity exposure apparatus by one embodiment of this invention. It is a figure explaining arrangement | positioning of a concave mirror, a semiconductor light-emitting device, and a fly eye lens. It is a figure explaining operation | movement of a light source unit. It is a figure explaining the relationship between the distance between semiconductor light emitting elements, and the distance from the center of a concave mirror to the center of the entrance plane of a fly-eye lens. It is a figure which shows an example of a base substrate. It is a figure which shows an example of a board | substrate. FIG. 8A is a front view of an example of a magnifying lens, and FIG. 8B is a side view thereof. It is a front view of a base substrate and a magnifying lens. It is a flowchart which shows an example of the manufacturing process of the TFT substrate of a liquid crystal display device. It is a flowchart which shows an example of the manufacturing process of the color filter board | substrate of a liquid crystal display device. It is a figure explaining operation | movement of a fly eye lens.

  FIG. 1 is a diagram showing a schematic configuration of a proximity exposure apparatus according to an embodiment of the present invention. The proximity 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 support 9, a chuck 10, a mask holder 20, and an exposure light irradiation device 30. It is configured. In addition to these, the proximity exposure apparatus includes a substrate transfer robot that loads the substrate 1 into the chuck 10 and unloads the substrate 1 from the chuck 10, a temperature control unit that performs temperature management in the apparatus, and the like.

  Note that the XY directions in the embodiments described below are examples, and the X direction and the Y direction may be interchanged.

  In FIG. 1, the chuck 10 is at an exposure position where the substrate 1 is exposed. A mask holder 20 for holding the mask 2 is installed above the exposure position. The mask holder 20 holds the periphery of the mask 2 by vacuum suction. An exposure light irradiation device 30 is disposed above the mask 2 held by the mask holder 20. At the time of exposure, exposure light from the exposure light irradiation device 30 passes through the mask 2 and is irradiated onto the substrate 1, whereby the pattern of the mask 2 is transferred to the surface of the substrate 1 and a pattern is formed on the substrate 1. .

  The chuck 10 is moved to a load / unload position away from the exposure position by the X stage 5. At the load / unload position, the substrate 1 is carried into the chuck 10 and the substrate 1 is carried out of the chuck 10 by a substrate transfer robot (not shown). The loading of the substrate 1 onto the chuck 10 and the unloading of the substrate 1 from the chuck 10 are performed using a plurality of push-up pins provided on the chuck 10. The push-up pin is housed inside the chuck 10 and is lifted from the inside of the chuck 10 to receive the substrate 1 from the substrate transfer robot and unload the substrate 1 from the chuck 10 when loading the substrate 1 onto the chuck 10. In doing so, the substrate 1 is delivered to the substrate transfer robot.

  The chuck 10 is mounted on the θ stage 8 via the chuck support 9, and a Y stage 7 and an X stage 5 are provided below the θ stage 8. The X stage 5 is mounted on an X guide 4 provided on the base 3 and moves along the X guide 4 in the X direction (the horizontal direction in FIG. 1). The Y stage 7 is mounted on a Y guide 6 provided on the X stage 5 and moves along the Y guide 6 in the Y direction (the depth direction in FIG. 1). The θ stage 8 is mounted on the Y stage 7 and rotates in the θ direction. The chuck support 9 is mounted on the θ stage 8 and supports the chuck 10 at a plurality of locations.

  The chuck 10 is moved between the load / unload position and the exposure position by the movement of the X stage 5 in the X direction and the movement of the Y stage 7 in the Y direction. At the load / unload position, the substrate 1 mounted on the chuck 10 is pre-aligned 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. Is done. At the exposure position, the X stage 5 is moved in the X direction and the Y stage 7 is moved in the Y direction, whereby the substrate 1 mounted on the chuck 10 is stepped in the XY direction. Further, the gap between the mask 2 and the substrate 1 is adjusted by moving and tilting the mask holder 20 in the Z direction (the vertical direction in FIG. 1) by a Z-tilt mechanism (not shown). Then, the substrate 1 is aligned by the movement of the X stage 5 in the X direction, the movement of the Y stage 7 in the Y direction, and the rotation of the θ stage 8 in the θ direction.

  In the present embodiment, the gap between the mask 2 and the substrate 1 is adjusted by moving and tilting the mask holder 20 in the Z direction. However, the chuck support base 9 is provided with a Z-tilt mechanism, The gap between the mask 2 and the substrate 1 may be adjusted by moving and tilting the chuck 10 in the Z direction.

  The exposure light irradiation device 30 includes a collimation lens group 32, a plane mirror 33, an illuminance sensor 35, and a light source unit 40. The light source unit 40 described later generates exposure light when the substrate 1 is exposed, and does not generate exposure light when the substrate 1 is not exposed. The exposure light generated from the light source unit 40 passes through the collimation lens group 32 to become a parallel light beam, is reflected by the plane mirror 33, and is applied to the mask 2. The pattern of the mask 2 is transferred to the substrate 1 by the exposure light applied to the mask 2, and the substrate 1 is exposed.

  An illuminance sensor 35 is disposed in the vicinity of the back side of the plane mirror 33. The plane mirror 33 is provided with a small opening that allows a part of the exposure light to pass therethrough. The illuminance sensor 35 receives the light that has passed through the opening of the plane mirror 33 and measures the illuminance of the exposure light. The measurement result of the illuminance sensor 35 is input to the light source unit 40.

  FIG. 2 is a view showing a light source unit of the proximity exposure apparatus according to the embodiment of the present invention. The light source unit 40 includes a base substrate 41, a semiconductor light emitting element 42, a magnifying lens 43, a fly eye lens 45, a control circuit 46, a cooling member 47, a cooling device 48, and a concave mirror 50. A plurality of semiconductor light emitting elements 42 are mounted on the base substrate 41. The base substrate 41 drives each semiconductor light emitting element 42 under the control of the control circuit 46. Each semiconductor light emitting element 42 is formed of a light emitting diode, a laser diode, or the like, and generates light that forms exposure light. The control circuit 46 controls driving of each semiconductor light emitting element 42 based on the measurement result of the illuminance sensor 35.

  In FIG. 2, nine semiconductor light emitting elements 42 are shown, but several hundred to several thousand semiconductor light emitting elements are used in an actual light source unit.

  The base substrate 41 is configured to be flat, and a plurality of semiconductor light emitting elements 42 are mounted on the same plane. Since the base substrate 41 is configured to be flat and the plurality of semiconductor light emitting elements 42 are mounted on the same plane, the plurality of semiconductor light emitting elements 42 can be easily installed on the same plane at the same mounting angle.

  A cooling member 47 is attached to the back surface of the base substrate 41. The cooling member 47 has a cooling water passage through which the cooling water flows, and cools each semiconductor light emitting element 42 by the cooling water supplied from the cooling device 48 to the cooling water passage. The cooling member 47 and the cooling device 48 are not limited to this, and may be an air cooling type including a heat radiating plate and a cooling fan.

  A magnifying lens 43 is provided corresponding to each semiconductor light emitting element 42 mounted on the base substrate 41, and each magnifying lens 43 expands the light generated from each semiconductor light emitting element 42. A concave mirror 50 having a parabolic mirror surface is provided in the optical path from the plurality of magnifying lenses 43 to the fly-eye lens 45, and the concave mirror 50 reflects the light magnified by the plurality of magnifying lenses 43. Irradiate the fly-eye lens 45. The fly-eye lens 45 forms exposure light having a uniform illuminance distribution by superimposing the light enlarged by the plurality of magnifying lenses 43 and reflected by the concave mirror. At this time, the light incident from the concave mirror 50 to the fly-eye lens 45 at an incident angle larger than the predetermined angle α deviates from the irradiation surface of the fly-eye lens 45 and is not used for forming exposure light.

  FIG. 3 is a diagram illustrating the arrangement of the concave mirror, the semiconductor light emitting element, and the fly-eye lens. In FIG. 3A, since the mirror surface of the concave mirror 50 is a paraboloid, all the light generated from the focal point F of the concave mirror 50 becomes parallel when reflected by the mirror surface of the concave mirror 50. Further, all the light incident in parallel with the normal MF passing through the focal point F of the concave mirror 50 is reflected at the mirror surface of the concave mirror 50 and is collected at the focal point F. In FIG. 3B, light incident obliquely at the same angle with respect to the normal MF passing through the focal point F of the concave mirror 50 is reflected at the mirror surface of the concave mirror 50 and gathers at a single point P having a different position depending on the incident angle. The distance of the point P from the center M of the concave mirror 50 is the same as the focal length f. Therefore, the point where the parallel incident light is reflected and collected by the mirror surface of the paraboloid of the concave mirror 50 is located on the circumference of the radius f from the center M of the concave mirror 50 indicated by a broken line in FIG.

  In the present invention, the distance between the base substrate 41 and the fly-eye lens 45 from the center of the semiconductor light-emitting element group mounted on the base substrate 41 to the center M of the concave mirror 50 and the incident surface of the fly-eye lens 45 from the center M of the concave mirror 50. Is arranged so that the distance to the center of the concave mirror 50 becomes equal to the focal length f of the concave mirror 50. Therefore, as shown in FIG. 3C, the center of the semiconductor light emitting element group mounted on the base substrate 41 and the center of the incident surface of the fly-eye lens 45 are set to a radius f from the center M of the concave mirror 50 indicated by a broken line. Located on the circumference of. Furthermore, in the present invention, the center position of the semiconductor light emitting element group on which the base substrate 41 and the fly-eye lens 45 are mounted on the base substrate 41 and the center position of the incident surface of the fly-eye lens 45 form the focal point F of the concave mirror 50. It arrange | positions so that it may become symmetrical across the normal line MF which passes. When the base substrate 41 and the fly-eye lens 45 are arranged in this way, as shown in FIG. 3C, the point P where the optical axes of the incident light from the respective semiconductor light emitting elements 42 to the concave mirror 50 are gathered. It is located at the center of the 45 incident surface.

  FIG. 4 is a diagram for explaining the operation of the light source unit. The point P where the optical axes of incident light from the respective semiconductor light emitting elements 42 to the concave mirror 50 gather is located at the center of the incident surface of the fly-eye lens 45, so that it is installed on the same plane of the base substrate 41 at the same mounting angle. The optical axis of the light generated from each semiconductor light emitting element 42 and obliquely incident on the concave mirror 50 at the same angle with respect to the normal MF passing through the focal point F of the concave mirror 50 is the emission of the concave mirror 50 as shown in FIG. Reflected by the mirror surface of the object surface, all goes toward the center of the entrance surface of the fly-eye lens 45. Therefore, in the present invention, the plurality of semiconductor light emitting elements 42 and the plurality of magnifying lenses 43 are expanded by the corresponding magnifying lenses 43 generated from each semiconductor light emitting element 42, and the optical axis of the light reflected by the concave mirror 50 is They are arranged so that they enter the center of the entrance surface of the fly-eye lens 45 within a predetermined angle α that does not deviate from the irradiation surface of the fly-eye lens 45.

At this time, there are two requirements necessary for the arrangement of the plurality of semiconductor light emitting elements 42 and the plurality of magnifying lenses 43, one of which is that the optical axis of each of the semiconductor light emitting elements 42 and the corresponding optical axis of the magnifying lens 43. It is in agreement. 4, the incident light of the fly-eye lens 45 from the center M of the concave mirror 50 to the incident surface of the fly-eye lens 45 with respect to a predetermined angle α where the incident light of the fly-eye lens 45 does not deviate from the irradiation surface of the fly-eye lens 45. The distance L to the center (in the present invention, equal to the focal length f of the concave mirror 50) and the distance h from the center to the end of the semiconductor light emitting element group are:
L = h / tan α
To satisfy the relationship.

  FIG. 5 is a diagram for explaining the relationship between the distance between the semiconductor light emitting elements and the distance from the center of the concave mirror to the center of the entrance surface of the fly-eye lens. The action of the concave mirror 50 can be considered by replacing it with a convex lens. Therefore, if the concave mirror 50 shown by a broken line in FIG. 5 is replaced with a convex lens 50 ′ having the same magnification, each of the semiconductors when L and h satisfy the above equation The optical axis of the light generated from the light emitting element 42 and enlarged by the corresponding magnifying lens 43 and reflected by the concave mirror 50 is incident on the fly eye lens 45 within a predetermined angle α that does not deviate from the irradiation surface of the fly eye lens 45. To be understood.

  In the above equation, α is a value determined according to the optical characteristics of the fly-eye lens 45, and varies depending on the type of fly-eye lens used. In the present invention, L is equal to the focal length f of the concave mirror 50, and is a value determined according to the optical characteristics of the concave mirror 50. Accordingly, in the present invention, the value of the focal length f of the concave mirror 50 and the value of the distance 2h from end to end of the semiconductor light emitting element group are set so as to satisfy the above formula according to the optical characteristics of the fly-eye lens to be used. decide. From the relationship of the above equation, the distance from the center M of the concave mirror 50 to the center of the entrance surface of the fly-eye lens 45 is reduced as the distance h from the center to the end of the semiconductor light-emitting element group is reduced. The light source unit 40 can be reduced in size by shortening.

  In FIG. 4, the incident angle of each optical axis from the concave mirror 50 to the fly-eye lens 45 depends on the arrangement of the plurality of semiconductor light emitting elements 42 and the plurality of magnifying lenses 43 that satisfy the two requirements described above. It is within a predetermined angle α that does not deviate from the surface. Therefore, in FIG. 2, a predetermined angle α where most of the light generated from each semiconductor light emitting element 42 and enlarged by the corresponding magnifying lens 43 and reflected by the concave mirror 50 does not deviate from the irradiation surface of the fly-eye lens 45. Is incident on the fly-eye lens 45 and used for forming exposure light. Therefore, when the exposure light is formed by superimposing the light generated from the plurality of semiconductor light emitting elements 42 by the fly-eye lens 45, the installation of each semiconductor light emitting element 42 is facilitated, and the light of each semiconductor light emitting element 42 is efficient. Often used, exposure light with high illuminance is formed.

  Further, in the present embodiment, in FIG. 2, each magnifying lens 43 magnifies the light generated from each semiconductor light emitting element 42 so that the light reflected by the concave mirror 50 becomes a substantially parallel light bundle. 50 is irradiated. By appropriately setting the magnification of the magnifying lens 43, the light reflected by the concave mirror 50 becomes a substantially parallel light bundle, so that almost all of the light reflected by the concave mirror 50 does not deviate from the irradiation surface of the fly-eye lens 45. The light enters the fly-eye lens 45 within a predetermined angle and is used to form exposure light. Therefore, the light of each semiconductor light emitting element 42 is used more efficiently, and exposure light with higher illuminance is formed.

  FIG. 6 is a diagram illustrating an example of the base substrate. In this example, the base substrate 41 is configured by combining a plurality of flat substrates 41a. Although nine substrates 41a are shown in FIG. 6, the actual base substrate 41 is configured by combining several tens to several hundreds of substrates 41a.

  When the base substrate 41 is configured by combining a plurality of flat substrates 41a, the required size of the base substrate 41 is set to an appropriate size according to the optical characteristics of the fly-eye lens 45 and the concave mirror 50, and the necessary semiconductor light emitting element described above is used. Group placement can be realized. That is, the value of the distance h from the center to the end of the semiconductor light emitting element group determined according to the optical characteristics of the fly-eye lens 45 and the concave mirror 50 can be realized.

FIG. 7 is a diagram illustrating an example of a substrate. In this example, each board | substrate 41a becomes a shape with the unevenness | corrugation which fits like the piece of a jigsaw puzzle in one direction. However, in the mounted state, it is not necessary that the substrates 41a are in contact with each other without any gap, and there may be an appropriate gap of about several mm between the substrates 41a. Each semiconductor light emitting element 42 mounted on each substrate 41a is arranged at the position of each vertex of a plurality of equilateral triangles arranged adjacent to each other with a gap as indicated by a broken line. When the vertical interval between the semiconductor light emitting elements 42 is d, the horizontal interval between the semiconductor light emitting elements 42 is:
√3 × d / 2
It becomes.

  In the example shown in FIG. 7, nine semiconductor light emitting elements 42 are mounted on one substrate 41a. However, the present invention is not limited to this, and the number of semiconductor light emitting devices is eight or less or ten on one substrate 41a. The above semiconductor light emitting element 42 may be mounted.

  FIG. 8A is a front view of an example of a magnifying lens, and FIG. 8B is a side view thereof. In this example, a plurality of magnifying lenses 43 are configured for each substrate 41 a corresponding to each substrate 41 a constituting the base substrate 41. Since the base substrate 41 is configured by combining a plurality of flat substrates 41a, and the plurality of magnifying lenses 43 are configured for each substrate 41a, the optical axis of each magnifying lens 43 can be easily adjusted for each substrate 41a. .

  In FIG. 8A, each magnifying lens 43 has a regular hexagonal cross section perpendicular to the optical axis, and is arranged adjacent to each other without a gap. FIG. 9 is a front view of the base substrate and the magnifying lens. The respective semiconductor light emitting elements 42 are arranged at the positions of the respective apexes of a plurality of equilateral triangles arranged adjacently without gaps, and the cross section perpendicular to the optical axis of each magnifying lens 43 is a regular hexagon so that each magnifying lens 43 is mutually connected. Since they are arranged adjacent to each other without a gap, the plurality of semiconductor light emitting elements 42 and the plurality of magnifying lenses 43 are uniformly arranged with high density, and the entire light source becomes small.

  In addition, when each semiconductor light emitting element 42 is arranged at the position of each vertex of a plurality of equilateral triangles arranged adjacent to each other with no gap, each substrate 41a is placed in a jigsaw puzzle piece in one direction as in the example shown in FIG. As shown in FIG. 6, when the substrates 41a are alternately combined in the reverse direction for each row, the substrates 41a are combined in the same direction in each row, and the positions of the substrates 41a are aligned in a row. The vertical dimension of the entire base substrate 41 can be made smaller than shifting each time.

  According to the embodiment described above, when the exposure light is formed by superimposing the light generated from the plurality of semiconductor light emitting elements 42 by the fly-eye lens 45, each semiconductor light emitting element 42 can be easily installed, The light from the semiconductor light emitting element 42 can be used efficiently to form exposure light with high illuminance.

  Further, each magnifying lens 43 irradiates the concave mirror 50 with the light generated from each semiconductor light emitting element 42 so that the light reflected by the concave mirror 50 becomes a substantially parallel light bundle. By using the light from the element 42 more efficiently, exposure light with higher illuminance can be formed.

  Further, the base substrate 41 is configured by combining a plurality of flat substrates 41a, and the plurality of magnifying lenses 43 are configured for each of the substrates 41a, so that the base substrate can be selected according to the optical characteristics of the fly-eye lens 45 and the concave mirror 50. It is possible to realize the necessary arrangement of the semiconductor light emitting element group by making the size of 41 appropriate, and to easily adjust the optical axis of each magnifying lens 43 for each substrate 41a.

  Further, the respective semiconductor light emitting elements 42 are arranged at the positions of the apexes of a plurality of equilateral triangles arranged adjacently without gaps, and the cross section perpendicular to the optical axis of each magnifying lens 43 is a regular hexagon so that each magnifying lens 43 Are arranged adjacent to each other without a gap, so that the plurality of semiconductor light emitting elements 42 and the plurality of magnifying lenses 43 can be uniformly arranged with high density, and the entire light source can be reduced in size.

  The exposure is performed using the proximity exposure apparatus of the present invention, or the substrate is exposed by irradiating the substrate with exposure light formed using the exposure light forming method of the proximity exposure apparatus of the present invention through a mask. As a result, the illuminance of the exposure light is increased, the exposure time is shortened, and the life of the light source of the exposure light is increased, so that the productivity of the display panel substrate can be improved.

  For example, FIG. 10 is a flowchart showing an example of the manufacturing process of the TFT substrate of the liquid crystal display device. In the thin film formation step (step 101), a thin film such as a conductor film or an insulator film, which becomes a transparent electrode for driving liquid crystal, is formed on the substrate by sputtering, plasma chemical vapor deposition (CVD), or the like. In the resist coating process (step 102), a photosensitive resin material (photoresist) is applied by a roll coating method or the like to form a photoresist film on the thin film formed in the thin film forming process (step 101). In the exposure step (step 103), the mask pattern is transferred to the photoresist film using a proximity exposure apparatus, a projection exposure apparatus, or the like. In the development step (step 104), a developer is supplied onto the photoresist film by a shower development method or the like to remove unnecessary portions of the photoresist film. In the etching process (step 105), a portion of the thin film formed in the thin film formation process (step 101) that is not masked by the photoresist film is removed by wet etching. In the peeling step (step 106), the photoresist film that has finished the role of the mask in the etching step (step 105) is peeled off with a peeling solution. Before or after each of these steps, a substrate cleaning / drying step is performed as necessary. These steps are repeated several times to form a TFT array on the substrate.

  FIG. 11 is a flowchart showing an example of the manufacturing process of the color filter substrate of the liquid crystal display device. In the black matrix forming step (step 201), a black matrix is formed on the substrate by processing such as resist coating, exposure, development, etching, and peeling. In the colored pattern forming step (step 202), a colored pattern is formed on the substrate by a dyeing method, a pigment dispersion method, a printing method, an electrodeposition method, or the like. This process is repeated for the R, G, and B coloring patterns. In the protective film forming step (step 203), a protective film is formed on the colored pattern, and in the transparent electrode film forming step (step 204), a transparent electrode film is formed on the protective film. Before, during or after each of these steps, a substrate cleaning / drying step is performed as necessary.

  In the TFT substrate manufacturing process shown in FIG. 10, in the exposure process (step 103), in the color filter substrate manufacturing process shown in FIG. 11, in the black matrix forming process (step 201) and the colored pattern forming process (step 202). In this exposure process, the proximity exposure apparatus or the exposure light forming method of the proximity exposure apparatus of the present invention can be applied.

DESCRIPTION OF SYMBOLS 1 Substrate 2 Mask 3 Base 4 X guide 5 X stage 6 Y guide 7 Y stage 8 θ stage 9 Chuck support 10 Chuck 20 Mask holder 30 Exposure light irradiation device 32 Collimation lens group 33 Plane mirror 35 Illuminance sensor 40 Light source unit 41 Base substrate 41a Substrate 42 Semiconductor light emitting element 43 Magnifying lens 45 Fly eye lens 46 Control circuit 47 Cooling member 48 Cooling device 50 Concave mirror

Claims (10)

A plurality of semiconductor light emitting elements that generate light that forms exposure light; and
A base substrate on which the plurality of semiconductor light emitting elements are mounted;
A plurality of magnifying lenses that are provided corresponding to each semiconductor light emitting element and that magnify light generated from each semiconductor light emitting element,
With a fly-eye lens,
A proximity exposure apparatus that forms exposure light by superimposing light expanded by the plurality of magnifying lenses on the fly-eye lens,
A concave mirror that is provided in an optical path from the plurality of magnifying lenses to the fly-eye lens, has a parabolic mirror surface, and reflects the light magnified by the plurality of magnifying lenses to irradiate the fly-eye lens; Prepared,
The base substrate is configured to be flat, and the plurality of semiconductor light emitting elements are mounted on the same plane,
The base substrate and the fly-eye lens are a distance from the center of the semiconductor light emitting element group mounted on the base substrate to the center of the concave mirror and a distance from the center of the concave mirror to the center of the entrance surface of the fly-eye lens. Is equal to the focal length of the concave mirror, and the center position of the semiconductor light emitting element group mounted on the base substrate and the center position of the entrance surface of the fly-eye lens sandwich a normal passing through the focal point of the concave mirror. Arranged so as to be symmetrical,
The plurality of semiconductor light emitting elements and the plurality of magnifying lenses are generated from each semiconductor light emitting element and enlarged by a corresponding magnifying lens, and an optical axis of light reflected by the concave mirror is from an irradiation surface of the fly-eye lens. A proximity exposure apparatus arranged so as to be incident on the fly-eye lens within a predetermined angle that does not deviate.   2. Each magnifying lens magnifies the light generated from each semiconductor light emitting element and irradiates the concave mirror so that the light reflected by the concave mirror becomes a substantially parallel light bundle. The proximity exposure apparatus described.   The proximity exposure apparatus according to claim 1, wherein the base substrate is configured by combining a plurality of flat substrates, and the plurality of magnifying lenses are configured for each of the substrates. Each semiconductor light emitting element is arranged at the position of each vertex of a plurality of equilateral triangles arranged adjacent to each other without a gap,
4. The proximity exposure apparatus according to claim 1, wherein each of the magnifying lenses has a regular hexagonal cross section perpendicular to the optical axis and is disposed adjacent to each other without a gap. 5. A plurality of semiconductor light emitting elements are mounted on a base substrate, and light forming exposure light is generated from each semiconductor light emitting element,
A plurality of magnifying lenses are provided corresponding to each semiconductor light emitting element, and the light generated from each semiconductor light emitting element is magnified by the corresponding magnifying lens,
An exposure light forming method of a proximity exposure apparatus that forms exposure light by overlapping light expanded by a plurality of magnifying lenses with a fly-eye lens,
In the optical path from the plurality of magnifying lenses to the fly-eye lens, a concave mirror that has a paraboloidal mirror surface, reflects the light magnified by the plurality of magnifying lenses and irradiates the fly-eye lens,
A base substrate is configured flat, and a plurality of semiconductor light emitting elements are mounted on the same plane,
The distance from the center of the semiconductor light-emitting element group mounted on the base substrate to the center of the concave mirror and the distance from the center of the concave mirror to the center of the entrance surface of the fly-eye lens are the focal length of the concave mirror. Equally, the center position of the semiconductor light emitting element group mounted on the base substrate and the center position of the incident surface of the fly-eye lens are arranged so as to be symmetric with respect to the normal passing through the focal point of the concave mirror,
A plurality of semiconductor light emitting elements and a plurality of magnifying lenses are generated from each semiconductor light emitting element and magnified by a corresponding magnifying lens, and the optical axis of the light reflected by the concave mirror does not deviate from the irradiation surface of the fly-eye lens. Arranged to enter the fly-eye lens within an angle,
An exposure light forming method for a proximity exposure apparatus, wherein light generated from a plurality of semiconductor light emitting elements and magnified by a plurality of magnifying lenses is reflected by a concave mirror and irradiated to a fly-eye lens.   6. The proxy according to claim 5, wherein each magnifying lens irradiates the concave mirror with the light generated from each semiconductor light emitting element so that the light reflected by the concave mirror becomes a substantially parallel light bundle. An exposure light forming method of a Mitty exposure apparatus.   7. The exposure light forming method for a proximity exposure apparatus according to claim 5, wherein a plurality of flat substrates are combined to form a base substrate, and a plurality of magnifying lenses are formed for each of the substrates. Each semiconductor light emitting element is arranged at the position of each vertex of a plurality of equilateral triangles arranged adjacent to each other without gaps,
The proximity according to any one of claims 5 to 7, wherein a cross section perpendicular to the optical axis of each magnifying lens is a regular hexagon, and each magnifying lens is arranged adjacent to each other without a gap. Exposure light forming method of exposure apparatus.   A method for manufacturing a display panel substrate, wherein the substrate is exposed using the proximity exposure apparatus according to any one of claims 1 to 4.   The substrate is exposed by irradiating the substrate with exposure light formed by using the exposure light forming method of the proximity exposure apparatus according to claim 5 through a mask. A manufacturing method of a display panel substrate.

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