JP6057072B2 - Light source device - Google Patents

Description

  The present invention relates to a light source device and an exposure apparatus provided with the same.

  Conventionally, an exposure apparatus has been used for fine processing using light. In recent years, exposure techniques have been developed in various fields, and are used for the production of relatively large patterns and three-dimensional microfabrication among microfabrication. More specifically, for example, an exposure technique is used for manufacturing an electrode pattern of an LED, a manufacturing process of MEMS (Micro Electro Mechanical Systems) represented by an acceleration sensor, and the like.

  In these exposure techniques, a discharge lamp with high brightness has been used as a light source for a long time. For example, Patent Document 1 below discloses a light irradiator that includes a lamp that emits ultraviolet rays as a light source and uses an aperture as a viewing angle adjustment mechanism. Conventionally, in order to control the viewing angle of the irradiation surface, an aperture is provided at the pupil position of the telecentric optical system and the diameter thereof is changed.

  Further, with the recent progress of solid-state light source technology, it has been studied to use a plurality of LEDs arranged in a matrix as a light source. For example, in Patent Document 2 below, a solid light source unit composed of a plurality of ultraviolet LED elements is used as a light source, and a fly-eye lens (a kind of lens array integrator) is disposed in an illumination optical system disposed between the light source and a mask. An exposure apparatus is disclosed.

JP 2008-164729 A JP 2004-335949 A

  When irradiating the irradiated object with the exposure apparatus, it is necessary to adjust the viewing angle of the light irradiated to the irradiated object as required. If the viewing angle is reduced, the depth of focus becomes deeper, so that accurate exposure is possible. However, the amount of light that can be captured at one time is reduced, and processing time is required. Conversely, if the viewing angle is increased, the depth of focus becomes shallow, which is not suitable for high-precision processing, but the amount of light that can be captured at a time increases, so processing in a short time is possible. As described above, in the exposure apparatus, the viewing angle of the light irradiated as the object to be irradiated is adjusted according to the balance between the required accuracy and the processing time.

  In the technique of Patent Document 1, an aperture is used for adjusting the viewing angle. By adjusting the aperture diameter or replacing it with another aperture of different diameter or shape, part of the light emitted from the lens array integrator is shielded according to the aperture diameter and the viewing angle is adjusted. Can do.

  However, according to this method, depending on the required viewing angle, it is necessary to adjust the diameter of the aperture each time, or to replace it with a suitable aperture, and there is a problem that processing takes time. Moreover, since it is necessary to prepare a plurality of types of apertures in advance for replacement, there is a problem that the management thereof becomes complicated.

  In view of the above problems, an object of the present invention is to provide a light source device capable of controlling a viewing angle on a light irradiation surface without using an aperture. Another object of the present invention is to provide an exposure apparatus using such a light source device.

The present invention is a light source device for irradiating light to an irradiated object,
A light source including a first light emitting unit and a second light emitting unit, a control unit capable of adjusting the amount of light separately for each of the first light emitting unit and the second light emitting unit,
A group of rod integrators comprising a plurality of rod integrators;
Having a lens array integrator on which light emitted from the rod integrator group is incident;
The rod integrator group includes a first rod integrator and a second rod integrator formed so as to surround an outer periphery of the first rod integrator,
The first rod integrator takes in the light emitted from the first light emitting unit and irradiates the first region of the lens array integrator with light,
The second rod integrator is configured to take light emitted from the second light emitting unit and irradiate light to a second region different from the first region of the lens array integrator. .

  According to the above configuration, the amount of light emitted from the emission surface of the first rod integrator and the amount of light emitted from the emission surface of the second rod integrator can be individually controlled by the control unit. The light emitted from the first rod integrator is applied to the first region of the lens array integrator with a uniform illuminance. Similarly, the light emitted from the second rod integrator is a uniform illuminance. The second region of the lens array integrator is irradiated.

  That is, the irradiation light amount can be adjusted for each different region on the entrance surface of the lens array integrator while keeping the illuminance within the same region uniform.

  Here, the second rod integrator is formed so as to surround the outer periphery of the first rod integrator. Thus, the second region on the lens array integrator that is irradiated with the light emitted from the second rod integrator is positioned outside the first region on the lens array integrator that is irradiated with the light emitted from the first rod integrator. The That is, the irradiation light quantity can be adjusted while keeping the illuminance in each region constant inside and outside the light incident surface of the lens array integrator.

  Therefore, for example, when the control unit is configured so that the amount of light from the second light source unit is substantially zero and the light is output only from the first light source unit, substantially only the first region on the lens array integrator is light. Is incident, and the light is not incident on the second region which is outside thereof. That is, the same function as the aperture that allows the inner light to pass and shields the outer light can be realized.

  As a result, when the light source device is used as an exposure device, the light intensity of each light source unit is adjusted by the control unit without adjusting the diameter of the aperture or replacing the aperture. The viewing angle of the irradiated light can be adjusted.

  Further, in the case of the configuration in which the viewing angle is adjusted using the aperture, there is a problem that the light use efficiency is low because the light emitted from the light source is partially blocked by the aperture. On the other hand, according to the configuration of the present invention, for example, the amount of light emitted from the second light emitting unit can be made zero in order to reduce the viewing angle, and thus there is an effect that the light use efficiency can be improved. .

  In the above configuration, the light emitted from the light source is once incident on the rod integrator before entering the lens array integrator. Thereby, the superposition of the incident light is performed.

  The light emitted from the light source has a certain divergence angle, and is reflected by the inner surface of the rod integrator for each angular component, and the light reaches a plurality of points on the light output surface of the rod integrator. When a light source in which a plurality of solid light source elements are arranged is used, the arrival position of the light emitted from each element varies depending on the position where each element is arranged, and they are made uniform by overlapping them. As a result, the light emitted from the rod integrator has a uniform light and dark pattern in the light source, and the arrangement pattern of each solid light source element is not reflected.

  Then, the light emitted from the rod integrator is incident on the light incident surface of the lens array integrator without reflecting the arrangement pattern of each solid light source element. Since the illuminance of the incident surface of each lens of the lens array integrator is uniform, the illuminance is uniform even on the irradiation surface of the irradiated object irradiated with the light emitted from the lens array integrator.

  Therefore, it is possible to irradiate the object from the lens array integrator with the light having a uniform illuminance distribution without reflecting the arrangement pattern of the plurality of solid light source elements constituting the light source.

  In particular, when the first light emitting unit and the second light emitting unit are composed of a plurality of LEDs, the above-described effect is remarkably exhibited.

  That is, when a plurality of LEDs are arranged, peripheral circuits such as a signal line and a switching element for supplying a current to each LED are required, so that the LEDs cannot be arranged without a gap. For this reason, the emitted light from the plurality of LEDs arranged with a separation shows an illuminance distribution reflecting the LED arrangement pattern on the irradiation surface.

  As described above, when light in a state where the LED arrangement pattern is reflected is directly incident on the light incident surface of the lens array integrator, the pattern is reflected in each lens of the lens array integrator. As a result, sufficient uniformity (uniformity) cannot be ensured on the work surface (light irradiation surface) that is the irradiation object.

  However, as described above, according to this configuration, since the light emitted from the light source is once incident on the rod integrator before entering the lens array integrator, the light emitted from the lens array integrator is irradiated. Even on the irradiation surface of the irradiated object, the illuminance is made uniform without reflecting the LED arrangement pattern.

  In the above configuration, the second rod integrator may be formed on the concentric axis of the first rod integrator.

Furthermore, the first rod integrator is formed in a cylindrical or elliptical column shape,
The second rod integrator may be formed in an annular column shape or an elliptic ring column shape.

  The rod integrator group may include a plurality of annular second rod integrators surrounding the first rod integrator. In this case, the 2nd light emission part for making light enter with respect to each 2nd rod integrator is provided corresponding to the number of 2nd rod integrators.

That is, the light source includes a plurality of the second light emitting units,
The control unit is configured to adjust the amount of light separately for each of the plurality of second light emitting units,
The rod integrator group includes a plurality of the second rod integrators formed so as to surround the outer periphery of the first rod integrator,
Each of the plurality of second rod integrators is configured to take in light emitted from different second light emitting units and irradiate the different second regions with light. .

  In this case, each of the second regions irradiated with the light emitted from each of the plurality of second rod integrators on the light incident surface of the lens array integrator has a second shape on the light incident surface of the lens array integrator. It is located outside the first region irradiated with light from one rod integrator. That is, one second region is formed outside the first region, and another second region is formed outside the first region. Hereinafter, another second region is formed outside the first region by the number corresponding to the number of second rod integrators. A region is formed. Thereby, the irradiation light quantity can be finely adjusted while maintaining the illuminance in each region on the inside and outside of the light incident surface of the lens array integrator.

  With this configuration, the light emitted from the plurality of second rod integrators is irradiated to different second regions of the lens array integrator with uniform illuminance. That is, it is possible to increase the number of regions in which the irradiation light amount can be adjusted. Thereby, the light quantity incident on the lens array integrator can be adjusted more finely. That is, substantially the same function as adjusting the aperture diameter in multiple steps can be realized, and thereby the viewing angle of the light applied to the irradiated object can be finely adjusted.

  Further, the light entrance surface of the lens array integrator may be connected to the light exit surface of the rod integrator group.

  The light emitted from the light exit surface of the rod integrator group maintains the spread angle of the light incident on the rod integrator. For example, when a solid light source element having a certain spread angle is used for the emitted light such as an LED as the first light emitting part and the second light emitting part, the emitted light from the rod integrator also has a spread angle. . Therefore, when the distance between the rod integrator group and the lens array integrator is wide, it may happen that a part of the light beam included in the light emitted from the rod integrator cannot be taken into the lens array integrator.

  Therefore, by configuring the light incident surface of the lens array integrator to be connected to the light output surface of the rod integrator group, almost all the light emitted from the rod integrator can be taken into the lens array integrator. Thereby, the utilization efficiency of light is improved.

  In addition, a configuration may be provided that includes a first optical member that images light emitted from the light source on the light incident surface of the rod integrator group. At this time, the 1st optical member can employ | adopt the structure which injects via optical members, such as a convex lens.

  With such a configuration, the light emitted from the light source can be condensed (imaged) on the light incident surface of the rod integrator group.

  Further, the light entrance surface of the rod integrator group may be connected to the light exit surface of the light source.

  In such a configuration, light emitted from the light source can be incident on the light incident surface of the rod integrator group with high efficiency.

  Moreover, it is good also as a structure provided with the 2nd optical member which images the light radiate | emitted from the rod integrator group on the incident surface of the light of a lens array integrator. At this time, the second optical member can adopt a configuration in which the light enters through an optical member such as a convex lens.

  Even in such a configuration, the emitted light from the rod integrator group can be condensed on the light incident surface of the lens array integrator, and almost all the emitted light from the rod integrator group is taken into the lens array integrator. It becomes possible.

  Further, the aperture is used by the light source device having the above characteristics and the exposure device having the projection optical system that projects the pattern image of the mask onto the photosensitive substrate by irradiating the light from the irradiation surface of the integrator onto the mask. Thus, an exposure apparatus that can adjust the viewing angle is realized.

  According to the light source device of the present invention, by adjusting the light amount of each light source unit by the control unit, it is possible to control the viewing angle on the light irradiation surface without using an aperture.

It is a schematic diagram which shows the structure of the optical system of a light source device. It is a schematic diagram which shows the structure of the optical system of a light source device. It is a schematic diagram which shows the structure of a light source. It is a schematic diagram which shows the light-incidence surface of a lens array integrator. It is the figure which showed typically the optical path from a light source to a to-be-irradiated object. It is the figure which showed typically the optical path from a light source to a to-be-irradiated object. It is a figure which shows the relationship between the visual angle of the light which injects into the arbitrary positions of the irradiation surface of a to-be-irradiated object, and intensity | strength. It is a schematic diagram which shows another structure of the optical system of a light source device. It is a schematic diagram which shows another structure of the optical system of a light source device. It is a schematic diagram which shows another structure of the optical system of a light source device. It is a schematic diagram which shows another structure of the optical system of a light source device. It is a schematic diagram which shows another structure of the optical system of a light source device. It is a schematic diagram which shows another structure of the optical system of a light source device. It is a schematic diagram which shows the structure of the optical system of exposure apparatus.

  The light source device of the present invention will be described with reference to the drawings. In each figure, the dimensional ratio in the drawing does not necessarily match the actual dimensional ratio.

  1 and 2 are schematic views showing the configuration of the optical system of the light source device. The light source device 1 includes a light source 11, a rod integrator group 13, and a lens array integrator 15. FIG. 2 shows the configuration of FIG. 1 in detail.

  The light emitted from the light source 11 enters the rod integrator group 13. The rod integrator group 13 irradiates the light incident surface 15s of the lens array integrator 15 with this light.

  Note that an object to be irradiated (not shown in FIG. 1) for irradiating light from the light source 11 is installed at the rear stage of the lens array integrator 15 (on the side opposite to the light source 11). An optical system such as a projection lens may be installed between the irradiation object and the lens array integrator 15 as necessary.

  The light source 11 includes a plurality of light emitting units (referred to as “LED elements” in the present embodiment). FIG. 3 is a schematic diagram showing the configuration of the light source 11. The light source 11 is configured by arranging a plurality of LED elements 21 on a substrate 10. The plurality of LED elements 21 constitute a light emitting unit 31, a light emitting unit 32a, a light emitting unit 32b, and a light emitting unit 32c for each region. The light emitting unit 31 corresponds to the “first light emitting unit”, and the light emitting unit 32 including the light emitting unit 32a, the light emitting unit 32b, and the light emitting unit 32c corresponds to the “second light emitting unit”.

  The control unit 17 adjusts the light amount of each light emitting unit (31, 32) constituting the light source 11. More specifically, the amount of light can be adjusted for each light emitting unit 31, 32 a, 32 b, 32 c for each light emitting unit. For example, the control unit 17 can increase only the light amount from the light emitting unit 31 or decrease only the light amount from the light emitting unit 32c. That is, common light quantity control may be performed for the plurality of LED elements 21 constituting the same light emitting unit.

  The rod integrator group 13 includes a plurality of rod integrators (2, 3a, 3b, 3c). The rod integrator 2 corresponds to the “first rod integrator”, and the rod integrator 3 including the rod integrator 3a, the rod integrator 3b, and the rod integrator 3c corresponds to the “second rod integrator”.

  Each rod integrator (2, 3a, 3b, 3c) is composed of a glass member or a cylindrical member having a mirror on the inner surface, and light incident on the incident surface is repeatedly reflected inside and the reflected light is superimposed. Thus, it has a function of uniforming the illuminance distribution of light on the exit surface while maintaining the orientation distribution of incident light.

  More specifically, the rod integrator 2 is composed of a cylindrical glass member, and the rod integrators 3a, 3b, 3c located on the outer periphery thereof are composed of an annular columnar glass member, so that the rod integrator group 13 can be formed.

  As another example, the rod integrator 2 is formed of a cylindrical member having a mirror on the inner surface, and each rod integrator 3a, 3b, 3c located on the outer periphery of the rod integrator 2 is also a ring with a mirror formed on the inner surface. The rod integrator group 13 can be formed by using a cylindrical member.

  In the present embodiment, the rod integrator 2 has a cylindrical shape, and each rod integrator 3 has an annular column shape concentric with the rod integrator 2 so as to surround the outer periphery of the rod integrator 2. More specifically, the rod integrator 3a is formed in an annular column shape surrounding the outer periphery of the rod integrator 2, and the rod integrator 3b is further configured in an annular column shape surrounding the outer periphery of the rod integrator 3a. 3c is comprised by the annular column shape which further surrounds the outer periphery of the rod integrator 3b.

  However, the rod integrator 2 may have a rectangular column shape, a polygonal column shape, or an elliptic column shape. In this case, each rod integrator 3 may have an annular column shape corresponding to the shape of the rod integrator 2.

  Each rod integrator (2, 3) has a function of making the illuminance uniform on the exit surface of the incident light. Each rod integrator (2, 3) has a different light source (31, 32) from which light is incident.

  That is, in the configuration of the present embodiment, the rod integrator 2 receives the light emitted from the light emitting unit 31, and the illuminance on the emission surface 2z is made uniform (see FIGS. 2 and 3). The rod integrator 3a receives the light emitted from the light emitting unit 32a, and the illuminance on the emission surface 3az is made uniform. The rod integrator 3b receives the light emitted from the light emitting unit 32b, and the illuminance on the emission surface 3bz is made uniform. The rod integrator 3c receives the light emitted from the light emitting unit 32c, and the illuminance on the emission surface 3cz is made uniform.

  Furthermore, each rod integrator (2, 3) irradiates light to a different region. FIG. 4 schematically shows the light incident surface 15 s of the lens array integrator 15. This will be described with reference to FIG.

  The light emitted from the rod integrator 2 is applied to the region 5 of the light incident surface 15 s of the lens array integrator 15. The light emitted from the rod integrator 3a is applied to the region 6a of the light incident surface 15s of the lens array integrator 15. The light emitted from the rod integrator 3b is applied to the region 6b of the light incident surface 15s of the lens array integrator 15. The light emitted from the rod integrator 3c is applied to the region 6c of the light incident surface 15s of the lens array integrator 15. The region 5 corresponds to the “first region”, and the region 6 including the region 6 a, the region 6 b, and the region 6 c corresponds to the “second region”.

  The lens array integrator 15 includes a plurality of lenses 22 and has a function of making the illuminance distribution uniform by superimposing the illuminance distributions of light incident on the incident surfaces of the respective lenses 22 on the irradiation surface. That is, the lens array integrator 15 receives the emitted light with uniform illuminance from each of the rod integrators (2, 3a, 3b, 3c), and distributes the illuminance distribution on the irradiation surface of the object to be irradiated after the lens array integrator 15. Irradiates with uniformized light.

  That is, according to the light source device 1, the light amount incident on each rod integrator (2, 3) can be adjusted separately by adjusting the light amount of each light emitting portion (31, 32) by the control unit 17. Thus, the amount of light incident on each of the regions (5, 6) for each light incident surface of the lens array integrator 15 can be adjusted.

  As shown in FIG. 4, the region 6 is located outside the region 5. Further, in the region 6, the region 6b is located outside the region 6a, and the region 6c is located outside the region 6b. In other words, the light amount of the light emitting unit corresponding to the rod integrator that enters light in the region located outside is reduced or substantially zero by reducing the light amount incident on the region located inside the light emitter. In particular, the amount of light emitted from the region located outside the lens array integrator 15 can be reduced or made zero.

  More specifically, a case where the control unit 17 significantly reduces the light amounts from the light emitting unit 32b and the light emitting unit 32c as compared with the light amounts from the light emitting unit 31 and the light emitting unit 32a will be described. Here, the light quantity from the light emission part 32b and the light emission part 32c is demonstrated as zero. In this case, light from the light source 11 is incident only on the rod integrators 2 and 3a, and light is not incident on the rod integrators 3b and 3c located outside the rod integrators 2 and 3a.

  For this reason, also on the light incident surface 15s of the lens array integrator 15, light is incident only on the regions 5 and 6a, and no light is incident on the regions 6b and 6c located outside thereof. As a result, the light taken in only the regions 5 and 6a located on the inner side of the lens array integrator 15 is irradiated to the irradiated object in the subsequent stage.

  That is, the diameter of the light beam incident on the lens array integrator 15 can be changed by adjusting the light emitting units (31, 32) that emit light by the control unit 17. This means that a function equivalent to an aperture that substantially shields the outside light and allows only the inside light to pass through can be realized.

  5 and 6 are schematic diagrams for explaining the above contents in more detail. Here, it is assumed that the light emitted from the lens array integrator 15 is projected onto the irradiation surface of the irradiation object 26 via the optical system 25.

  For simplicity of explanation, the light source 11 includes a light emitting unit 31, a light emitting unit 32a, and a light emitting unit 32b. That is, in FIG. 3, the light source 11 is not provided with the light emission part 32c, and the light emission part 32b is demonstrated as what is a light emission part located in the outermost part. Similarly, the rod integrator group 13 includes a rod integrator 2, a rod integrator 3a, and a rod integrator 3b. In the following description, it is assumed that the light incident surface 15s of the lens array integrator 15 is divided into a region 5, a region 6a, and a region 6b from the inside toward the outside.

  FIGS. 5A and 6A correspond to optical path diagrams in the case where the light emitting unit 31, the light emitting unit 32a, and the light emitting unit 32b are all turned on by the control unit 17. FIG. On the other hand, FIG. 5B and FIG. 6B correspond to optical path diagrams when the inner light emitting unit 31 and the light emitting unit 32a are turned on by the control unit 17 and the outer light emitting unit 32b is turned off. .

  5A and 5B show the optical path of the light incident on the central portion of the light incident surface of each lens 22 constituting the lens array integrator 15 in the subsequent stage of the lens array integrator 15. Show. On the other hand, FIG. 6A and FIG. 6B relate to the latter stage of the lens array integrator 15 in FIG. 5 and the light incident on the end of the light incident surface of each lens 22 constituting the lens array integrator 15. The optical path is shown.

  FIG. 5A and FIG. 6A will be described. Light emitted from the light emitting unit 31 is incident on the rod integrator 2 and light with uniform illuminance is emitted. The outgoing light from the rod integrator 2 is incident on the region 5 of the lens array integrator 15. More specifically, the light enters the lens in the region 5. The light 41 emitted from the light emission surface in the region 5 of the lens array integrator 15 forms an image on the irradiation surface of the irradiation object 26 via the optical system 25.

  In FIG. 5 (a), as described above, the optical path of the light incident on the center of the light incident surface of each lens constituting the lens array integrator 15 is shown. Of the 26 irradiation surfaces, the light is condensed at a condensing position 26p near the optical axis. Note that the light incident on the end of the light incident surface of each lens constituting the lens array integrator 15 is condensed at a condensing position 26q away from the optical axis, as shown in FIG.

  Similarly, the emitted light from the light emitting unit 32a is incident on the rod integrator 3a, and this emitted light is incident on the lens in the region 6a of the lens array integrator 15. The light 42 emitted from the light emission surface of the region 6 a of the lens array integrator 15 forms an image on the irradiation surface of the irradiation object 26 via the optical system 25.

  The emitted light from the light emitting unit 32b is incident on the rod integrator 3b, and this emitted light is incident on the lens in the region 6b of the lens array integrator 15. The light 43 emitted from the light emitting surface in the region 6 b of the lens array integrator 15 forms an image on the irradiation surface of the irradiation object 26 via the optical system 25.

  On the other hand, in the case of FIG. 5B and FIG. 6B, since the light emitting unit 32b is turned off by the control unit 17, there is no light incident on the rod integrator 3b. Therefore, there is no light incident on the lens in the region 6b of the lens array integrator 15, and no light 43 is emitted from the light emitting surface of the region 6b of the lens array integrator 15.

  Thereby, the comparison of FIG. 5 (a) and FIG. 5 (b) and the comparison of FIG. 6 (a) and FIG. 6 (b) show that the configuration of FIG. 5 (b) and FIG. It can be seen from FIG. 5A and FIG. 5B that the viewing angle of light on the irradiated surface of the irradiated object 26 can be narrowed.

  FIG. 7 is a diagram showing the relationship between the viewing angle and the intensity of light incident on an arbitrary position on the irradiation surface of the irradiation object 26 in FIG. FIG. 7A shows a case where all of the light emitting unit 31, the light emitting unit 32a, and the light emitting unit 32b are turned on (FIGS. 5A and 6A), and FIG. This corresponds to the case where the light emitting unit 31 and the light emitting unit 32a are turned on and the light emitting unit 32b outside thereof is turned off (FIG. 5B and FIG. 6B), respectively.

  7A and 7B are diagrams in which the light emitting unit 32b is turned off as compared with FIG. 7A in which all the light emitting unit 31, the light emitting unit 32a, and the light emitting unit 32b are turned on. 7 (b) shows that the viewing angle is limited.

  From the above, it can be seen that the viewing angle of the light incident on the irradiation surface of the irradiation object 26 can be adjusted by adjusting the light emitting units (31, 32) that emit light by the control unit 17.

[Another configuration example]
Another configuration of the light source device will be described with reference to the drawings. In addition, you may combine suitably each separate structural example shown below.

  (1) The light incident surface 15s of the lens array integrator 15 may be connected to the light emitting surface of the rod integrator group 13 as in the light source device 1a shown in FIG. The same applies to other configurations below.

  Since each rod integrator constituting the rod integrator group 13 maintains the angle component of the incident light, the emitted light from the rod integrator group 13 has a spreading angle. By adopting the configuration of the light source device 1a, almost all of the emitted light from the rod integrator group 13 can be taken into the lens array integrator 15. Thereby, the emitted light from the light source 11 can be efficiently incident on the lens array integrator 15.

  The term “joint” used here is a matter of course when the top of the lens on the light incident surface of the lens array integrator 15 and the light emitting surface of the rod integrator group 13 are completely in contact with each other. The light incident surface of the rod integrator group 13 may cover the 15 light incident surface. Further, the case where the maximum outer diameter of the rod integrator group 13 is smaller than the maximum outer diameter of the lens array integrator 15 includes the case where the distance between them is about the difference in diameter.

  (2) As in the light source device 1 b shown in FIG. 9, an optical member 51 is provided between the light source 11 and the rod integrator group 13, and light emitted from the light source 11 is transmitted through the optical member 51 to the rod integrator group 13. A configuration may be adopted in which an image is formed on the incident surface 13s. The optical member 51 corresponds to a “first optical member”.

  Thereby, the emitted light from the light source 11 can be condensed on the light incident surface 13 s of the rod integrator group 13.

  (3) A configuration may be adopted in which a convex lens 52 is further provided between the light source 11 and the optical member 51 as in the optical device 1c shown in FIG.

  The convex lens 52 is arranged at a position where the focal position on the optical member 51 side coincides with the focal position on the light source 11 side of the optical member 51. Further, the light incident surface 13 s of the rod integrator group 13 is disposed at a position where the optical member 51 projects the vicinity of the exit surface of the convex lens 52. Although not shown, an optical system that collimates light from the light source 11 may be added to the front stage of the convex lens 52.

  In this configuration, the light emitted from the light source 11 is once collected by the convex lens 52 at the focal position on the optical member 51 side of the convex lens 52 and then incident on the optical member 51. Light from the vicinity of the convex lens 52 is imaged on the light incident surface 13 s of the rod integrator group 13 by the optical member 51. Thereby, similarly to another structure (2), the emitted light from the light source 11 can be condensed on the light incident surface 13 s of the rod integrator group 13.

  Here, “coincidence of focal positions” is a concept including a case where there is some deviation as well as a case where focal positions completely coincide. The lens used here may be a spherical lens, and the spherical lens has spherical aberration. The focal position of the convex lens 52 is the waist position of the beam produced by the light passing through the periphery of the lens. The focal position of the optical member 51 on the convex lens 52 side is preferably in the range of a distance corresponding to ± 10% of the waist diameter in the optical axis direction.

  In FIG. 10, the light emitted from the light source 11 is incident on the optical member 51 via one convex lens 52, but may be incident on the optical member 51 via a plurality of lenses. .

  (4) As in the optical device 1 d shown in FIG. 11, the light incident surface 13 s of the rod integrator group 13 may be connected to the light emitting surface of the light source 11.

  When each light emission part (31, 32) which comprises the light source 11 is comprised by several LED element, since the emitted light from an LED element has a spreading angle, each light emission part (31, 32) and rod integrator If the distance of the light incident surface 13 s of the group 13 is more than a certain distance, a part of the emitted light cannot be taken into the rod integrator group 13. With the configuration shown in FIG. 11, the light emitted from the light source 11 can be incident on the light incident surface 13 s of the rod integrator group 13 with high efficiency.

  (5) As in the optical device 1 e shown in FIG. 12, an optical member 53 is provided between the rod integrator group 13 and the lens array integrator 15, and this optical member 53 uses the light emitted from the rod integrator group 13 as the lens array integrator 15. Alternatively, the light may be arranged so as to form an image on the light incident surface 15s. The optical member 53 corresponds to a “second optical member”.

  Thereby, the emitted light from the rod integrator group 13 can be condensed on the light incident surface 15 s of the lens array integrator 15, and almost all the emitted light from the rod integrator group 13 can be taken into the lens array integrator 15. It becomes possible.

  (6) A configuration in which a convex lens 54 is further provided between the rod integrator group 13 and the optical member 53, as in the optical device 1f shown in FIG.

  The convex lens 54 is arranged at a position where the focal position on the optical member 53 side coincides with the focal position on the light source 11 side of the optical member 53. The light incident surface 15 s of the lens array integrator 15 is disposed at a position where the optical member 53 projects the vicinity of the exit surface of the convex lens 54. Although not shown, an optical system for collimating the light from the light source 11 may be added to the front stage of the rod integrator group 13.

  In this configuration, the emitted light from the rod integrator group 13 is once condensed at the focal position on the optical member 53 side of the convex lens 54 by the convex lens 54 and then incident on the optical member 53. Light from the vicinity of the convex lens 54 is imaged on the light incident surface 15 s of the lens array integrator 15 by the optical member 53. In this case as well, almost all of the light emitted from the rod integrator group 13 can be taken into the lens array integrator 15.

  FIG. 13 shows a configuration in which light emitted from the rod integrator group 13 is incident on the optical member 53 via one convex lens 54, but may be incident on the optical member 53 via a plurality of lenses. I do not care.

[After the lens array integrator]
FIG. 14 is a schematic diagram showing the configuration of the optical system of the exposure apparatus 80 including the light source device 1. An irradiation lens 61 as a projection optical system 60 and a mask 62 are provided at the subsequent stage of the lens array integrator 15, and a projection lens 63 is provided as necessary. A mask 62 is set at the irradiation position of the irradiation lens 61, and a photosensitive substrate 64 to be a target for printing a pattern image of the mask 62 is set after the mask 62.

  In the exposure apparatus 80 shown in FIG. 14, when light is emitted from the light source 11, the illuminance distribution of light on the light exit surface of the rod integrator group 13 while maintaining the orientation distribution of the light via the rod integrator group 13. Is made uniform. Further, this light is condensed via the lens array integrator 15, and the light intensity difference corresponding to the incident angle is made uniform and emitted to the projection optical system 60.

  The projection optical system 60 projects the pattern image of the mask 62 onto the photosensitive substrate 64 directly or via the projection lens 63. In the case of an exposure apparatus without the projection lens 63, a type in which the mask 62 and the photosensitive substrate 64 are brought into contact (contact exposure), and a type in which the distance between the mask 62 and the photosensitive substrate 64 is set from several micrometers to several tens of micrometers (proxy). Mitty exposure).

  According to the exposure apparatus 80 provided with the light source device 1, in the light source device 1, by adjusting the light emitting units (31, 32) that are made to emit light by the control unit 17, The viewing angle can be adjusted. Therefore, the photosensitive substrate 64 can be irradiated with light having a viewing angle corresponding to a condition required in the exposure process without changing the aperture diameter or exchanging the aperture.

  Furthermore, according to the exposure apparatus 80 provided with the light source device 1, even when each light emitting part (31, 32) constituting the light source 11 is realized by a configuration in which a plurality of LED elements are arranged, the plurality of LED elements. Thus, the lens array integrator 15 can take in light in which the illuminance distribution is made uniform without reflecting the arrangement pattern. As a result, there is no difference in light intensity depending on the location on the photosensitive substrate 64 that is the object to be irradiated. Accordingly, even an LED element whose arrangement pattern is easily reflected in light can be used as the light source 11 of the exposure apparatus 80.

  14 shows the light source device 1 shown in FIGS. 1 and 2, the light source devices 1a, 1b, 1c, 1d, 1e, and 1f shown in other configuration examples may be adopted. .

[Another embodiment]
Hereinafter, another embodiment will be described.

  <1> In the above-described embodiment, the rod integrator group 13 has a configuration in which a plurality of rod integrators 3 (3a, 3b, 3c) are surrounded by the outer periphery of the rod integrator 2. However, any configuration may be used as long as at least one rod integrator 3 is provided on the outer periphery of the rod integrator 2. And the light source 11 should just be set as the structure provided with the light emission part according to the number of rod integrators. In this case, the light emission part 31 and the light emission part 32 which can adjust light quantity collectively for the light emission parts 32a, 32b, and 32c are provided. You should prepare.

  Also in this configuration, the viewing angle of the light incident on the irradiation surface of the irradiation object 26 can be adjusted by adjusting the light amount for the light emitting units 31 and 32 by the control unit 17.

  Conversely, by increasing the number of rod integrators 3 (second rod integrators) surrounding the outer periphery of the rod integrator 2, and increasing the number of light emitting units 32 (second light emitting units) according to the number of rod integrators 3, It becomes possible to finely adjust the viewing angle of light incident on the irradiation surface of the irradiated object 26.

  <2> In the above-described embodiment, the configuration in which the light source 11 is realized by the plurality of LED elements 21 has been described. However, as long as the light amount can be adjusted by the control unit 17 for each light emitting unit (31, 32), the element constituting the light source 11 is not limited to the LED element. For example, a lamp can be used.

  <3> In the above embodiment, the control unit 17 is provided outside the light source 11. However, the control unit 17 may be mounted on the same substrate as the substrate 10 on which the light source 11 is mounted.

  <4> In the above-described embodiment, a bilateral telecentric optical system may be configured by disposing a collimating lens and an optical aperture between the light source 11 and the rod integrator group 13. Similarly, an optical system may be arranged between the lens array integrator 15 and the irradiated object 26 to constitute a double-sided telecentric optical system.

  <5> The exposure apparatus 80 including the light source device 1 is used in a projection exposure system and a proximity exposure system in which the mask 62 and the photosensitive substrate 64 do not contact each other, and a contact exposure system in which the mask 62 and the photosensitive substrate 64 contact each other. Is possible.

1: Light source device 2: Rod integrator (first rod integrator)
2z: Light exit surface of rod integrator 2 3 (3a, 3b, 3c): Rod integrator (second rod integrator)
3az: Light exit surface of rod integrator 3a 3bz: Light exit surface of rod integrator 3b 3cz: Light exit surface of rod integrator 3c 5: First region 6 (6a, 6b, 6c) of lens array integrator: First lens array integrator 2 region 10: Substrate 11: Light source 13: Rod integrator group 13s: Light incident surface of rod integrator group 15: Lens array integrator 15s: Light incident surface of lens array integrator 17: Controller 21: LED element 22: Lens 25: Optical System 26: Object 26p, 26q: Condensing position 31: Light emitting part (first light emitting part)
32 (32a, 32b, 32c): light emitting part (second light emitting part)
41: Light emitted from the lens array integrator region 5 42: Light emitted from the lens array integrator region 6a 43: Light emitted from the lens array integrator region 6b 51: Optical member 52: Convex lens 53: Optical member 54: Convex lens 60: Projection optical system 61: Irradiation lens 62: Mask 63: Projection lens 64: Photosensitive substrate 80: Exposure apparatus

Claims (2)

A light source device for irradiating an object with light,
A light source including a first light emitting unit and a second light emitting unit, a control unit capable of adjusting the amount of light separately for each of the first light emitting unit and the second light emitting unit,
A group of rod integrators comprising a plurality of rod integrators;
Having a lens array integrator on which light emitted from the rod integrator group is incident;
The rod integrator group includes a first rod integrator and a second rod integrator formed so as to surround an outer periphery of the first rod integrator,
The first rod integrator takes in the light emitted from the first light emitting unit and irradiates the first region of the lens array integrator with light,
It said second rod integrator, Ri configuration der for irradiating light to the second area different from the first region of the lens array integrator captures light emitted from the second light emitting portion,
The second rod integrator is formed on a concentric axis of the first rod integrator;
The first rod integrator has a column shape,
The light source device , wherein the second rod integrator has an annular column shape . The first rod integrator has a cylindrical or elliptical column shape,
The light source device according to claim 1 , wherein the second rod integrator has an annular column shape or an elliptic column shape.

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