JP6315720B2 - Exposure illumination device - Google Patents

Description

The present invention relates to an exposure illumination apparatus, and more particularly to an exposure illumination apparatus that irradiates an exposure surface with light beams emitted from a plurality of LED elements that are discretely arranged at intervals.

  Conventionally, various exposure illumination apparatuses that expose a substrate are known. The exposure illumination apparatus irradiates an exposure surface with a light beam emitted from a light source via an optical device such as a lens system to expose the substrate. As a light source of such an exposure illumination apparatus, a light source having high luminance is selected, and as shown in Patent Document 1 and Patent Document 2, for example, a UV lamp or a halogen lamp has been conventionally used.

However, UV lamps and halogen lamps used in exposure illumination apparatuses generally have a short life although high luminance can be obtained. For this reason, the replacement frequency is increased and the cost is increased.

  For this reason, in recent years, it has been studied to use LED elements having a long lifetime. That is, LED elements having a large capacity capable of obtaining high luminance have been developed in recent years, and their use in exposure illumination apparatuses has been actively studied. For the exposure illumination apparatus using such an LED element, for example, the technique disclosed in Patent Document 3 is referred to.

That is, in the exposure illumination apparatus of the same document 3, a plurality of LED elements (chip LEDs) are used as a light source, and a light beam emitted from the plurality of LED elements is converted into a tapered rod lens (tapered light guide) or a rod lens. The exposure surface is irradiated via (light guide). The LED element is provided on the incident end face of the tapered rod lens, and the dimension of the LED element is set smaller than the dimension of the incident end face of the tapered rod lens.

JP 2007-017897 A JP 2012-238673 A JP 2003-330109 A

By the way, when an LED element is used as a light source as in the exposure illumination apparatus described above, a plurality of LED elements are discretely arranged at predetermined intervals due to problems of wiring and heat generation, as shown in FIG. .
However, when a plurality of LED elements are discretely arranged in this way and the size of the LED elements is set to be smaller than the size of the incident end face of the tapered rod lens as described above, Even at the exit end face, the luminous flux becomes discrete and a surface light source cannot be obtained, resulting in a decrease in energy density between the luminous fluxes emitted from adjacent LED elements. There is a risk that stable exposure of the substrate may be hindered.
For this reason, there has been a strong demand for the development of an exposure illumination apparatus that can ensure uniform brightness distribution of light fluxes and can stably expose a substrate at the maximum illuminance even when a plurality of LED elements are used.

The present invention has been made in view of such circumstances, and it is possible to ensure uniformity of a light beam emitted from a light source in which a plurality of LED elements are discretely arranged at intervals and a sufficient substrate to ensure sufficient illuminance. An object of the present invention is to provide an exposure illumination apparatus capable of performing exposure.

In order to achieve the above object, the invention of claim 1 relating to an exposure illumination apparatus is an exposure illumination for irradiating an exposure surface with a light beam emitted from a light source having a plurality of LED elements discretely arranged at intervals. The apparatus has a size that gradually increases along the optical axis direction of the light beam emitted from the LED element on each light emitting side of the plurality of LED elements, and the size of the output end surface is larger than the size of the incident end surface of the light beam. A plurality of set tapered first light guides are provided adjacent to each other, and the size of the light beam emitted from the LED element on the incident end face of the first light guide is determined by the incidence of the first light guide. While being set larger than the end face , the LED element is provided on the incident end face of the first light guide, and the size dimension of the light flux in the direction perpendicular to the optical axis direction emitted from the LED element on the incident end face is: Set larger than the dimension of the incident end face The plurality of first light guides have a rectangular exit end face, and the end portions of the exit end face are densely joined to each other in a direction orthogonal to the optical axis direction of the light flux, so that However, they are provided adjacent to each other in a direction orthogonal to each other .

According to the present invention, the dimension gradually increases along the optical axis direction of the luminous flux emitted from the LED element on the emission side of each of the plurality of LED elements, and the dimension of the emission end face is larger than the incident end face dimension of the luminous flux. A plurality of tapered first light guides which are set large are provided adjacent to each other, and the magnitude of the light beam emitted from the LED element on the incident end face of the first light guide is determined by the first light guide. The LED element is set to be larger than the incident end face , and the LED element is provided on the incident end face of the first light guide, and the size dimension of the light flux in the direction perpendicular to the optical axis direction emitted from the LED element on the incident end face is The plurality of first light guides are formed in a rectangular shape on the exit end face, and the ends of the exit end face are joined closely to each other in a direction perpendicular to the optical axis direction of the light beam. By adjusting the Since it was decided to be provided adjacent to be aligned in mutually direction, from the incident end face of the first light guide body, while a light beam of size comparable to the size of the incident end face, the tapered In one light guide, the light beam emitted from the LED element can be gradually increased in size while being repeatedly reflected, and even in a light source having a plurality of LED elements arranged at intervals, It is possible to prevent the light beam from being discrete at the exit end face of one light guide so that the light beam is emitted from one large surface light source, and so on, between the light beams emitted from adjacent LED elements. A reduction in energy density can be prevented. Thereby, the uniformity of the light beam emitted from the light source and sufficient illuminance can be ensured, and stable substrate exposure can be performed.

In addition, in the tapered first light guide, the light beam emitted from the LED element is repeatedly reflected while reducing the reflection angle, so that a nearly parallel light beam can be easily generated. The production efficiency can be improved.

Furthermore, the size of the light flux emitted from the LED element at the incident end face of the first light guide body, Ru can than the incident end face of the first light guide member reliably set large.

Furthermore, it is possible to further prevent the luminous flux from becoming discrete at the exit end face of the first light guide so that the luminous flux is emitted from one large surface light source. Ru can be further reliably prevented to cause deterioration in energy density between light beams.
The plurality of first light guides have parallel portions parallel to the optical axis direction on the light emission side, and the adjacent first light guides are joined to each other. Since surface bonding can be performed in between, a stable bonding state can be ensured (Claim 2 ).
The first light guide member may be a tapered rod (claim 3).

Provided on the exit side of the first light guide and extending in parallel along the optical axis direction of the light beam, the size of the incident end face on which the light beam emitted from the first light guide is incident and the incident light beam If the size of the exit end face to be emitted is set to be substantially equal and the second light guide is provided to uniformize the light flux emitted from the first light guide, the light flux is emitted at the exit end face of the light guide. The light beam emitted from the first light guide can be made more uniform, for example, by further preventing the light from becoming discrete and allowing the light beam to be emitted from one large surface light source. (Claim 4 ).

Second light guide member may be a being joined to the ends of the incident end face of the second light guide body on the end of the exit end face of the first light guide body (claim 5).
An optical member is provided between the first light guide and the second light guide, and the second light guide condenses the light beam emitted from the first light guide via the optical member. The second light guide can be made compact, for example, the second light guide can be made to have a size corresponding to the size of the condensed light beam. (Claim 6 ).
Second light guide member may be a rod integrator or fly's eye integrator (claim 7).

According to the present invention, it is possible to ensure the uniformity of the luminous flux emitted from a light source in which a plurality of LED elements are discretely arranged at intervals and sufficient illuminance to perform stable substrate exposure.

It is a block diagram which shows the whole structure of the exposure illumination apparatus which shows 1st Embodiment of this invention. It is a block diagram which shows the whole structure of the light source of the exposure illumination apparatus. It is a figure for demonstrating the technical effect in the said 1st Embodiment. It is another figure for demonstrating the technical effect in the said 1st Embodiment. It is a block diagram which shows the whole structure of the exposure illumination apparatus which shows 2nd Embodiment of this invention. It is a block diagram which shows the whole structure of the exposure illumination apparatus which shows 3rd Embodiment of this invention. It is a block diagram which shows the whole structure of the exposure illumination apparatus which shows 4th Embodiment of this invention. It is a figure for demonstrating the subject in the conventional exposure illumination apparatus which employ | adopted the LED element.

Hereinafter, first to fourth embodiments of the present invention will be described in detail with reference to the drawings.

[First embodiment]
A first embodiment of the present invention will be described in detail with reference to FIGS. FIG. 1 is a block diagram showing an outline of the overall configuration of an exposure illumination apparatus showing a first embodiment of the present invention, FIG. 2 is a front view showing the overall configuration of a light source in the exposure illumination apparatus, and FIG. The figure for demonstrating the technical effect in a form, FIG. 4 is another figure for demonstrating the technical effect in 1st Embodiment.

The outline of the exposure illumination apparatus of the present invention will be described with reference to FIG. 1. The exposure illumination apparatus 1 includes a light source 10, a first light guide 20, a second light guide 30, and an optical member 40. A configuration in which the dimension of the light beam emitted from the light source 10 in the direction orthogonal to the optical axis direction 70 is gradually increased along the optical axis direction 70, and the exposure surface 80 is exposed while uniforming the luminance distribution of the light beam. It has become. A substrate 81 to be exposed is provided on the exposure surface 80 via a mask 82. That is, the exposure of this embodiment is proximity exposure, and employs a non-contact exposure method in which the exposure is performed by setting the gap between the substrate 81 and the mask 82 to about several μm to several hundred μm.

The light source 10 has a plurality of LED elements 11, and the LED elements 11 have a rectangular shape and are discrete with predetermined intervals in the height direction and the depth direction on the substrate 12, as shown in FIG. Are arranged. The LED element 11 is a chip LED in the present invention. The LED element 11 is directly provided outside the incident end face 21 of the first light guide 20, and the size of the LED element 11 is set so that the incident end face 21 is covered so that the entire incident end face 21 is covered. Each size is set to be larger than the size in the vertical direction and the depth direction. That is, the size of the light flux in the direction orthogonal to the optical axis direction emitted from the LED element 11 at the incident end face 21 of the first light guide 20 is larger than the dimension of the incident end face 21 of the first light guide 20. Is also set larger.

The first light guide 20 is provided adjacent to each light emitting side of the plurality of LED elements 11 and is a rod. More specifically, the first light guide 20 is a tapered rod integrator composed of a columnar light guide (rod) or a tubular light guide (rod) whose inner surface is a reflection surface. Etc. are formed. In other words, the first light guide 20 has a tapered shape, and the incident end face 21 and the outgoing end face 22 have a rectangular shape. The first light guide 20 gradually increases in size along the optical axis direction 70 of the light beam emitted from the LED element 11, and the size of the emission end surface 22 is set larger than the size of the incident end surface 21 of the light beam. Has been. With the first light guide 20 having such a configuration, the dimension of the light flux emitted from the light source 10 in the direction orthogonal to the optical axis direction can be gradually increased.

Here, the plurality of first light guides 20 are closely joined to each other at the end portions of the emission end face 22 so as to be aligned with each other in a direction orthogonal to the optical axis direction 70 of the light beam. Provided. More specifically, the plurality of first light guides 20 have a parallel part 23 parallel to the optical axis direction 70 on the light emission side, and are densely joined to each other via the joint surface 24 of the parallel part 23. Has been.

The second light guide 30 is provided on the emission side of the first light guide 20, and the end of the incident end face 31 of the second light guide 30 is emitted from the first light guide 20. It is joined to the end of the end face 22. The second light guide 30 is a rod. More specifically, the first light guide 30 is a rod integrator composed of a columnar light guide (rod) or a tubular light guide (rod) whose inner surface is a reflective surface, such as synthetic quartz. It is formed with. That is, the second light guide 30 extends in parallel along the optical axis direction 70 of the light beam, and is incident with the size of the incident end face 31 on which the light beam emitted from the first light guide 20 is incident. The size of the exit end face 32 that emits the luminous flux is set equal or substantially equal, and has a function of making the luminance distribution of the luminous flux emitted from the first light guide 20 uniform. The incident end face 31 and the outgoing end face 32 of the second light guide 30 are rectangular.

The optical member 40 is provided on the emission side of the second light guide 30. In other words, the optical member 40 includes the first relay lens 50 and the second relay lens 60 that are configured by lenses having convex power, and refracts the light beam emitted from the second light guide 30. It has a function of irradiating the exposure surface 80 while making it.

As described above, according to the first embodiment, the first light guide 20 is provided adjacent to the emission side of each of the plurality of LED elements 11, and the first light guide 20 is a tapered rod. As shown, the dimension gradually increases along the optical axis direction 70 of the luminous flux emitted from the LED element 11, the dimension of the outgoing end face 22 is set larger than the dimension of the incident end face 21 of the luminous flux, and the first light guide. Since the size of the light beam emitted from the LED element 11 on the incident end surface 21 of the body 20 is set to be larger than that of the incident end surface 21 of the first light guide 20, As shown in FIG. 3, while the light beam having the same size as the size of the incident end surface 21 is incident from the incident end surface 21, the LED element 11 is separated from the LED element 11 in the tapered first light guide 20. The emitted light beam is repeatedly reflected and its dimensions It can be gradually increased. As a result, as shown in FIG. 4, even in the light source 10 having the plurality of LED elements 11 discretely arranged on the substrate 12 at a predetermined interval, the emission end face of the first light guide 20 In FIG. 22, it is possible to prevent the luminous flux from becoming discrete and to emit the luminous flux from one large surface light source. For example, the energy density decreases between the luminous fluxes emitted from the adjacent LED elements 11. This can be prevented. Thereby, the uniformity of the luminance distribution of the light beam emitted from the light source 10 and sufficient illuminance can be ensured, and stable substrate exposure can be performed.

Returning to FIG. 3, in the tapered first light guide 20, the light beam emitted from the LED element 11 is repeatedly reflected while reducing the reflection angle, so that a nearly parallel light beam can be easily generated. As a result, the manufacturing efficiency of the substrate 81 can be improved.

That is, in the present invention, the angle θ of the light beam that looks into the substrate 81 from the second relay lens 60 is reduced, and the numerical aperture (NA) is reduced. For this reason, “blur” on the exposure surface 80 can be appropriately prevented, and the gap between the substrate 81 and the mask 82 can be set relatively large. Exchange frequency can be reduced. Further, it is possible to appropriately prevent the exposure time of the substrate 81 from becoming longer by maximizing the density of energy projected onto the exposure surface 80. Thereby, the manufacturing efficiency of the substrate 81 can be improved.

Further, the plurality of first light guides 20 are provided adjacent to each other so that the ends of the emission end face 22 are closely joined to each other and aligned in a direction perpendicular to the optical axis direction 70 of the light beam. As a result, the adjacent LED elements can be configured such that the light beam can be further emitted from one large surface light source by further preventing the light beam from becoming discrete at the emission end face 22 of the first light guide 20. It is possible to more reliably prevent the energy density from being lowered between the light beams emitted from the light source 11.

Furthermore, since the plurality of first light guides 20 have parallel portions 23 parallel to the optical axis direction 70 on the light emission side, the parallel portions 23 are densely joined to each other. In addition, surface bonding can be performed between the adjacent first light guides 20, and a stable bonding state can be ensured.

Furthermore, it has the 2nd light guide 30 in the output side of the 1st light guide 20, and the 2nd light guide 30 is used as a rod integrator in detail from a rod, and is parallel along the optical axis direction 70. FIG. The size of the incident end face 31 that receives the light beam emitted from the first light guide 20 and the size of the outgoing end face 32 that emits the incident light are set equal or substantially equal. Since the function of uniforming the luminance distribution of the light beam emitted from the first light guide 20 is provided, it is possible to further prevent the light beam from becoming discrete on the light emission end face of the light guide. The luminance distribution of the light beam emitted from the first light guide 20 can be made more uniform, for example, by allowing the light beam to be emitted from a large surface light source. Note that, as described above, the first light guide 20 has the parallel portion 23 and the parallel portion 23 may cause a decrease in energy density. However, the first light guide 20 may be incident on the second light guide 30. Thus, it is possible to reliably prevent such a decrease in energy density and to make the luminance distribution of the light beam uniform.

[Second Embodiment]
Next, a second embodiment of the present invention will be described in detail with reference to FIG. In the description of the second embodiment, the same reference numerals as those in the first embodiment described above are used as the same configuration, and the description thereof may be omitted.

The exposure illumination apparatus 2 in the second embodiment shows an example in which the position of the second light guide is changed. That is, in the second embodiment, the optical member 400 is provided between the first light guide 20 and the second light guide 200, and the second light guide 200 is interposed via the optical member 400. The light beam emitted from the first light guide 20 is condensed while being refracted so that the light beam is reduced and incident.

The second light guide 200 is a rod, as in the first embodiment described above. More specifically, the second light guide 200 is a rod integrator composed of a columnar light guide or a tubular light guide whose inner surface is a reflective surface, and is made of synthetic quartz or the like. That is, the second light guide 200 extends in parallel along the optical axis direction 70 of the light beam, and emits the incident light beam with the size of the incident end surface 201 on which the light beam emitted from the optical member 400 is incident. The size of the outgoing end face 202 is set equal or substantially equal, and has a function of making the luminance distribution of the light beam emitted from the first light guide 20 uniform.

According to the second embodiment, by adopting such a configuration, the size of the second light guide 200 can be made to correspond to the size of the condensed light beam, and the second light guide The body 200 can be made compact.

Further, since the light beam emitted from the first light guide 20 is condensed and incident on the second light guide 200 through the optical member 400 while being refracted, the luminance distribution of the light beam is further uniformized. .

Also in the second embodiment, the optical member 400 is configured by a lens having a convex power, and includes a first relay lens 401 and a second relay lens 402. The second light guide 200 also has an optical member 500 on the exit side. The optical member 500 is a lens having a convex power, and the first relay lens 501 and the second relay lens. 502. The light beam emitted from the second light guide 200 is irradiated to the exposure surface 80 while being refracted.

[Third embodiment]
Next, a third embodiment of the present invention will be described in detail with reference to FIG. In the description of the third embodiment, the components denoted by the same reference numerals as those in the first embodiment and the second embodiment described above may be omitted because they are the same components. To do.

The exposure illumination apparatus 3 in the third embodiment shows an example in which the configuration of the second light guide in the second embodiment is changed. That is, in the third embodiment, the second light guide 300 is a fly eye, and is formed of synthetic quartz or the like. More specifically, in the second light guide 300, a first fly eye 301a including a large number of lenses 301b is provided on the incident end face 301 side, and a second fly eye including a large number of lenses 302b on the output end face 302 side. The fly eye integrator is provided with an eye 302a, and the light beam emitted from the first light guide 20 is condensed while being refracted through the optical member 400 to reduce the light beam and enter the fly eye integrator.

In the second light guide 300 according to the fly eye integrator, a large number of lenses 301b and 302b correspond one-to-one on the fly eyes 301a and 302a. For example, the lens 301b of the first fly eye 301a includes: , And has a focal position on the corresponding lens 302b of the second fly's eye 302a. Therefore, a light source image of a light beam incident on the first fly eye 301a can be formed on each lens 302b of the second fly eye 302a, and uniform illumination can be performed. Note that the second light guide 300 formed of a fly-eye integrator has a size of the incident end face 301 that receives the light beam emitted from the optical member 400 and a size of the outgoing end face 302 that emits the incident light beam. The dimension is set to be equal or substantially equal, and has a function of making the luminance distribution of the light beam emitted from the first light guide 20 uniform.

In the third embodiment, the optical member 400a is a single relay lens 401a having a convex power. Further, an optical member 500a is also provided on the emission side of the second light guide 300, and the optical member 500a is also a relay lens 501a having a convex power. The light beam emitted from the second light guide 300 is irradiated to the exposure surface 80 while being refracted through the optical member 500a.

[Fourth embodiment]
Next, a fourth embodiment of the present invention will be described in detail with reference to FIG. In the description of the fourth embodiment, the components denoted by the same reference numerals as those in the first to third embodiments described above may be omitted because they are the same components. To do.

The exposure illumination device 4 in the fourth embodiment shows an example in which the configuration around the light source 10 in the first to third embodiments is changed. That is, in the fourth embodiment, a configuration in which the light source 10 is spaced outward from the first light guide 20 is shown, and each of the plurality of LED elements 11 provided in the light source 10 and the first light guide. The size of the light beam emitted from the LED element 110 on the incident end face 21 of the first light guide 20 is provided by re-imaging the light emitting surface of the LED element 11 by providing the optical member 110 with the body 20. Is set to be larger than the incident end face 21 of the first light guide 20.

By adopting such a configuration of the fourth embodiment, even when the dimension of the LED element 11 is smaller than the incident end face 21 of the first light guide 20, the luminous flux emitted from the LED element 11 is reduced. The size can be easily made larger than the size of the incident end face 21 of the first light guide 20, and the degree of freedom in selecting the dimensions of the LED element 11 can be ensured.

The optical member 110 includes a lens having a convex power, and includes a first relay lens 111 and a second relay lens 112, and magnifies the light beam emitted from the LED element 11 while refracting it. The light is incident on the first light guide 20.

In the fourth embodiment, a position changing mechanism for changing the relative positions of the light source 10, the first relay lens 111, the second relay lens 112, and the first light guide 20 is provided. It is good also as a structure which adjusts the magnitude | size of the light beam which injects into the optical body 20 suitably.

The present invention is an exposure that can ensure stable uniformity of substrate exposure by ensuring uniformity of luminance distribution of a light beam emitted from a light source in which a plurality of LED elements are discretely arranged at predetermined intervals and sufficient illuminance. A lighting device is provided. As a result, the manufacturing cost can be reduced, which greatly contributes to the development of various manufacturing industries.

1: Exposure illumination device 2: Exposure illumination device 3: Exposure illumination device 4: Exposure illumination device 10: Light source 11: LED element (chip LED)
12: Substrate 20: First light guide 21: Incident end face 22: Outgoing end face 23: Parallel portion 24: Joint surface 30: Second light guide 31: Incident end face 32: Outgoing end face 40: Optical member 50: First 1 relay lens 60: second relay lens 70: optical axis direction 80: exposure surface 81: substrate 82: mask 110: optical member 111: first relay lens 112: second relay lens 200: second guide Optical body 201: incident end face 202: outgoing end face 300: second light guide 301: incident end face 301a: first fly eye 301b: lens 302: outgoing end face 302a: second fly eye 302b: lens 400: optical member 400a: optical member 401: first relay lens 401a: relay lens 402: second relay lens 500: optical member 500a: optical member 501: first relay lens 501 : Relay lens 502: second relay lens

Claims (7)

An exposure illumination apparatus that irradiates an exposure surface with a light beam emitted from a light source having a plurality of LED elements discretely arranged at intervals,
On the emission side of each of the plurality of LED elements, the size gradually increases along the optical axis direction of the light beam emitted from the LED element, and the size of the emission end surface is set larger than the size of the incident end surface of the light beam. A plurality of tapered first light guides adjacent to each other,
The size of the light beam emitted from the LED element at the incident end face of the first light guide is set larger than the incident end face of the first light guide ,
The LED element is provided on an incident end face of the first light guide, and a size dimension of a light flux in a direction orthogonal to an optical axis direction emitted from the LED element on the incident end face is larger than a dimension of the incident end face. Is also set larger,
The plurality of first light guides has a rectangular shape on the emission end face, and the end portions of the emission end face are densely joined to each other in a direction orthogonal to the optical axis direction of the light flux. An exposure illumination apparatus, which is provided adjacent to each other in a direction orthogonal to the optical axis direction . Wherein the plurality of first light guide body according to claim 1, wherein said has an optical axis parallel to the direction parallel portion, being joined between the flat Gyobu mutually on the emission side of the light beam Exposure lighting equipment. The exposure illumination apparatus according to claim 1, wherein the first light guide is a tapered rod. A size of an incident end surface on which the light beam emitted from the first light guide is incident along the optical axis direction of the light beam and the incident light beam are provided on the emission side of the first light guide. the size of the exit end face for emitting the set to be substantially equal, according to claim 1 to claim 3, characterized in that a second light guide for homogenizing the light beam emitted from the first light guide body The exposure illumination apparatus as described in any one of them. It said second light guide body, according to claim 4, characterized in that it is joining the ends of the incident end face of the second light guide body on the end of the exit end face of the first light guide body Exposure lighting equipment. An optical member is provided between the first light guide and the second light guide, and the light beam emitted from the first light guide via the optical member is condensed to the second light guide. The exposure illumination apparatus according to claim 5 , wherein the exposure illumination apparatus is made incident on a light guide body. The exposure illumination apparatus according to claim 6 , wherein the second light guide is a rod integrator or a fly eye integrator.

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