KR20140123055A - Exposure optical system, exposure apparatus, and exposure method - Google Patents

Abstract

Provided are an exposure apparatus and exposure method for performing high-definition exposure by suppressing side lobes around a main beam in an aperture array by an aperture shape of a microlens. The shielding portion 66b is provided on the emission side of the microlens 64a to move the position of the side lobe Bb in the vicinity of the focus position of the microlens 64a. Before passing through the second aperture array 68, the main beam Ba is about 4 mu m and the side lobe Bb is in the range of about 7.2 mu m from the center of the main beam Ba, The relative strength is suppressed to about 1/10. The laser beam B having a light intensity distribution that can ignore the side lobe Bb around the main beam Ba can be obtained as a result of narrowing the laser beam B at the second aperture array 68. [

Description

TECHNICAL FIELD [0001] The present invention relates to an exposing optical system, an exposing apparatus and an exposing method,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exposure optical system, an exposure apparatus and an exposure method, and more particularly to an exposure optical system using a microlens array having a spatial light modulation element and an aperture array for regulating the aperture shape on the microlens emission side, .

There is known an image exposure apparatus having an exposure head and exposing a desired pattern onto a photosensitive material by the exposure head. The exposure head of this type of image exposure apparatus basically comprises a light source, a spatial light modulation element in which a plurality of pixel sections independently modulating the light irradiated from the light source independently in accordance with a control signal are arranged, And an imaging optical system for imaging an image formed by the light modulated by the light source on the photosensitive material.

As an example of the structure of the exposure head of the image exposure apparatus, there is a digital micro mirror device (hereinafter referred to as " DMD ") as a light modulation device having a light source and a plurality of micro mirrors, and a plurality of micro mirrors And a microlens array in which a plurality of microlenses for individually focusing light beams are arranged (see, for example, Japanese Patent Laid-Open No. 2004-1244).

According to this configuration using the microlens array, even if the size of the image exposed on the photosensitive material is enlarged, the light flux from each pixel portion of the spatial light modulation element is condensed by each microlens of the microlens array, The pixel size (= spot size of each light beam) of the exposed image in the exposure image is narrowed and kept small so that the sharpness of the image can be maintained at a high level.

The exposure head disclosed in Patent Document 1 further includes an aperture array on the emission side of the micro lens array, and the aperture array is provided with a plurality of apertures for individually limiting the plurality of light beams. By the action of the aperture array, each light beam is shaped so that the pixel size on the photosensitive material becomes a constant size, and crosstalk between adjacent pixels is prevented.

However, as another factor for lowering the sharpness of the exposed image in the image exposure apparatus, stray light originating from the spatial light modulation element or the ambient light is generated, and the stray light reaches the photosensitive material. As described in Patent Document 1, when one aperture array is provided for each microlens on the emission side of the microlens array, the stray light is removed and a high total extinction ratio (the entire pixel portion ON state and the entire pixel portion OFF state However, in order to achieve the object of removing the stray light only by the first aperture array disposed on the emission side of the microlens array, it is necessary to adjust the phase of each of the light beams converged by the microlens array The size of each opening and the position of the first opening array must be very strictly determined in accordance with the diameter of the first opening array, and it is difficult to adjust and maintain the alignment.

An object of the present invention is to provide an exposure optical system, an exposure apparatus, and an exposure method for performing high-definition exposure by suppressing side lobes around a main beam in an aperture array by an aperture shape of a microlens in consideration of the above facts.

According to a first aspect of the present invention, there is provided a spatial light modulator comprising a spatial light modulation element in which pixel portions for modulating light from a light source are arranged, a microlens array in which microlenses for condensing the light modulated in the spatial light modulation element are arranged, A first aperture array provided on the aperture of the first aperture array with respect to an optical axis of the microlens and having an aperture shape and an outer shape of the aperture, A first imaging optical system for imaging the light modulated by the spatial light modulation element into the microlens array; and a second imaging optical system for focusing the light condensed by the microlens array on the photosensitive material A second imaging optical system for imaging the microlens array at a converging position of the microlens array, To provide an exposure optical system comprising a second aperture array arranged an aperture to narrow the light emitted by each.

According to the present invention, unnecessary light (side lobe) of the beam narrowed in the second aperture array is diffused by the mask provided in the first aperture array larger than the aperture diameter of the second aperture array, whereby unnecessary light can be efficiently cut.

According to a second aspect of the present invention, there is provided an exposure optical system including a transmissive portion, which is in the shape of a rectangle and the mask, at the center of the mask with the optical axis of the microlens as a center.

According to the present invention, unnecessary light can be efficiently cut without reducing the light amount of the main beam by making the portion including the optical axis, which is the center of the mask, a transmissive portion.

According to a third aspect of the present invention, there is provided an exposure optical system in which the mask is a concentric annular lens about the optical axis of the microlens.

According to the above invention, when the shape of the microlenses is circular around the optical axis, it is possible to make an exposure optical system that exposes with a beam of a light amount distribution having a small deviation with respect to the circumferential direction.

A fourth aspect of the present invention provides the exposure optical system, wherein the mask is a concentric rectangle centered on the optical axis of the microlens.

According to the above invention, when the shape of the microlens is a rectangle centering on the optical axis, it is possible to make an exposure optical system that exposes with a beam of a light quantity distribution with a small deviation.

A fifth aspect of the present invention provides an exposure optical system in which the light-shielding portion and the transmissive portion are composed of an opaque portion and a transparent portion of a film attached to the emission side of the microlens.

According to the present invention, a mask is formed by making a part of the transparent film opaque, so that accurate mask processing can be performed with a small number of holes.

According to a sixth aspect of the present invention, there is provided an exposure optical system, wherein the mask is a chrome mask formed on the micro lens exit side.

According to the present invention, by forming a mask with a light-shielding film made of chrome, an exposure optical system can be obtained that has a mask which can provide a high optical density with few omissions.

A seventh aspect of the present invention provides an exposure optical system in which an outer peripheral portion of an opening portion of the first aperture array is an opaque portion.

According to the present invention, by making the outer peripheral portion of the opening portion an opaque light shielding portion, the shape of the transmissive portion of the microlens can be defined by the mask, and the number of parts and the number of air can be reduced.

An eighth aspect of the present invention provides an exposure optical system in which the light source is a semiconductor laser (LD).

According to the present invention, by using the monochromatic laser light, the light quantity distribution can be easily controlled, and an exposure optical system with high reliability and high image quality can be obtained.

A ninth aspect of the present invention is a light-emitting device comprising: a lens for condensing light from a light source; a first aperture having an aperture-like opening portion for regulating the transmission of light to the emission side of the lens; A mask provided in the opening of the first opening and shielding the light transmitted through the opening and having an opening shape and an outer shape that are similar to each other, a first imaging optical system for imaging the light onto the lens, There is provided an exposure optical system having a second imaging optical system for forming light on a photosensitive material and a second aperture for arranging an aperture for narrowing the light emitted from the lens at a light condensing position of the lens.

According to the present invention, unnecessary light (side lobe) of the beam narrowed at the second aperture by the mask provided in the first aperture is diffused larger than the diameter of the second aperture, whereby unnecessary light can be efficiently cut.

A tenth aspect of the present invention provides an exposure apparatus for exposing a predetermined pattern to a photosensitive material using the exposure optical system provided in any one of the first to ninth aspects.

According to the present invention, unnecessary light (side lobe) of the beam narrowed in the second aperture array or the aperture by the mask is diffused larger than the second aperture diameter, whereby unnecessary light can be efficiently cut without reducing the light quantity of the main beam .

An eleventh aspect of the present invention provides an exposure method for exposing a predetermined pattern to a photosensitive material using an exposure apparatus provided by the tenth form.

According to the present invention, unnecessary light (side lobe) of the beam narrowed in the second aperture array or the aperture by the mask is diffused larger than the second aperture diameter, whereby unnecessary light can be efficiently cut without reducing the light quantity of the main beam .

(Effects of the Invention)

According to the present invention, since the aperture shape of the microlens can suppress the side lobe around the main beam in the aperture array, high-definition exposure can be performed.

1 is a conceptual diagram showing an essential part of an exposure apparatus according to an embodiment of the present invention.
2 is a perspective view showing a main part of an exposure head according to an embodiment of the present invention.
3 is a perspective view showing an example of a DMD according to an embodiment of the present invention.
4 is a perspective view showing the ON-OFF state of the DMD according to the embodiment of the present invention.
5 is a conceptual diagram showing the arrangement of optical systems after the DMD according to the embodiment of the present invention.
6 is a conceptual diagram showing a light amount distribution at a conventional microlens converging position.
7 is a conceptual diagram showing a cause of non-uniformity of the optical system according to the embodiment of the present invention.
8 is a conceptual diagram showing the relationship between the conventional first aperture array and the light amount distribution.
9 is a conceptual diagram showing the relationship between the first aperture array and the light amount distribution according to the embodiment of the present invention.
10 is a conceptual diagram showing the relationship between the first aperture array and the light amount distribution, and the relationship between the second aperture array and the light amount distribution according to the embodiment of the present invention.
11 is a conceptual diagram showing the influence of the first aperture array on the light amount distribution according to the embodiment of the present invention.
12 is a conceptual diagram showing an opening shape of a first opening array according to another embodiment of the present invention.
13 is a conceptual diagram and a formula showing the relationship between the aperture shape of the first aperture array and the light intensity on the focal plane of the microlens according to the embodiment of the present invention.
Fig. 14 is a conceptual diagram and formula showing the relationship between the aperture shape of the first aperture array and the light intensity on the focal plane of the microlens according to the embodiment of the present invention.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

<Overall configuration>

As shown in Figs. 1 and 2, the exposure apparatus 10 according to the present embodiment is provided with a flat plate-like moving stage 14 for holding and holding a sheet-shaped photosensitive material P on its surface. Two guides 20 extending along the stage moving direction are provided on the upper surface of the thick plate-like mounting table 18 supported by a plurality of (for example, four) leg portions 16. The movable stage 14 is arranged such that its longitudinal direction is directed to the stage moving direction and is supported so as to be reciprocally movable along the guide 20. [ The exposure apparatus 10 is also provided with a stage driving device (not shown) for driving the moving stage 14 as the sub scanning means along the guide 20.

At the center of the mounting table 18, a gate 22 in the form of a crisscross bridge is provided so as to extend over the moving path of the moving stage 14. [ Each of the ends of the gate 22 is fixed to both sides of the mount 18. A scanner 24 is provided on one side of the gate 22 and a plurality of sensors 26 are provided on the other side to detect the leading edge and trailing edge of the photosensitive material P have. The scanner 24 and the sensor 26 are respectively attached to the gate 22 and fixedly disposed upstream of the movement path of the moving stage 14. [ Further, the scanner 24 and the sensor 26 are connected to a controller (not shown) for controlling them.

The scanner 24 includes a plurality (14 in the figure) of exposure heads 28 arranged in a substantially matrix shape of m rows and n columns, for example. The exposure area 30 by each exposure head 28 is a rectangular shape with the short side in the sub scanning direction. Thus, in accordance with the movement of the movable stage 14, a strip-shaped exposed area 31 is formed in the photosensitive material P for each of the exposure heads 28. [

The plurality of exposure heads 28 are formed by a light source (for example, a semiconductor laser (LD) or the like) not shown in the figure for emitting a laser beam having a wavelength of, for example, 400 nm and a laser beam emitted from the light source, For example, a DMD 34 shown in Fig. 3 as a spatial light modulation device modulating every pixel portion. The DMD 34 is connected to a controller (not shown) having a data processing section and a mirror drive control section. The data processing section of the controller generates a control signal for driving and controlling each micromirror 74 (described later) in the use area on the DMD 34 for each exposure head 28 on the basis of the inputted image data. The mirror drive control unit controls the angle of the reflecting surface of each micromirror 74 of the DMD 34 for each exposure head 28 based on the control signal generated by the image data processing unit.

5 shows the optical system after the DMD 34 in a conceptual view. A main optical system for imaging the laser beam B reflected by the DMD 34 onto the photosensitive material P is disposed on the light reflecting side (emitting side and irradiation side) of the DMD 34. [ The main optical system includes a first imaging optical system 52 for magnifying a beam modulated by the DMD 34, a second imaging optical system 58 for imaging a beam on the photosensitive material P, A first aperture array 66 disposed closest to the emission side of the microlens array 64 and a second aperture array 68 disposed at the focal position of the microlens array 64 ).

The first imaging optical system 52 includes, for example, an incident-side lens 52A and an emergence-side lens 52B, and the DMD 34 is disposed on the focal plane of the lens 52A. The lens 52A and the lens 52B have the same focal plane and the microlens array 64 is disposed on the focal plane on the emission side of the lens 52B. The second imaging optical system 58 also includes, for example, a lens 58A on the incident side and a lens 58B on the exit side. The lens 58A and the lens 58B have the same focal plane, The focal position of the microlens array 64 in which the aperture array 68 is disposed is the focal plane of the lens 58A. And the photosensitive material P is disposed on the focal plane on the exit side of the lens 58B.

The first imaging optical system 52 expands the image by the DMD 34 and forms an image on the microlens array 64. Further, the second imaging optical system 58 images and projects an image passing through the microlens array 64 onto the photosensitive material P. The first imaging optical system 52 and the second imaging optical system 58 all emit a plurality of light beams from the DMD 34 as light beams substantially parallel to each other.

3, the DMD 34 used in the present embodiment is formed by stacking a plurality (for example, 1024 x 768) very small Mirror (micro-mirror 74) are arranged in a lattice shape. For each pixel, a rectangular micromirror 74 supported by a support is provided at the uppermost portion. A material having a high reflectance such as aluminum is deposited on the surface of the micromirror 74, for example.

When a digital signal is recorded in the SRAM cell 72 of the DMD 34, each micromirror 74 supported on the support is tilted at any one of 占 degrees with respect to the substrate side on which the DMD 34 is disposed, Loses. 4A shows a state in which the micromirror 74 is inclined at + alpha ° in which the micromirror 74 is in an ON state and FIG. 4B shows a state in which the micromirror 74 is inclined at-alpha DEG in which the micromirror 74 is in an OFF state . Therefore, by controlling the inclination of the micromirror 74 in each pixel of the DMD 34 in accordance with the image signal as shown in Fig. 4, the laser beam B incident on the DMD 34 is incident on each micromirror 74, (74).

4 shows an example of a state in which a part (one micromirror portion) of the DMD 34 is enlarged and the micromirror 74 is controlled to + alpha DEG or-alpha DEG. ON OFF control of each of the micromirrors 74 is performed by a controller not shown in the drawing connected to the DMD 34. [

<Micro Lens Array>

The microlens array 64 has a plurality of microlenses 64a corresponding to the respective micromirrors 74 on the DMD 34 arranged in a two-dimensional shape of, for example, about 1024 x 768. In this embodiment, as one example, each microlens 64a is a flat convex lens having a plane of incidence and a convex surface of emission, and a flat convex lens formed of quartz glass having a focal length of 100 mu m is used. Also, a biconvex lens or the like may be used instead of the above example. The microlenses 64a and the connection portions connecting them in an array form may be integrally formed by the same material to form a microlens array 64 or a plurality of openings corresponding to each of the micromirrors 74 And each microlens 64a may be inserted into each of the formed base openings.

The first aperture array 66 and the second aperture array 68 are formed with a plurality of apertures corresponding to the respective microlenses 64a and the first aperture array 66 is formed on the exit side of the microlens array 64 And the second aperture array 68 are disposed spaced apart from the microlens array 64. The microlens array 64 is disposed at a position spaced apart from the microlens array 64 by a predetermined distance.

In the present embodiment, the first aperture array 66 is formed by providing a chrome mask (light-shielding film made of chrome) at portions other than the openings on the exit side of the microlens 64a, or by applying a permeable / semi- Alternatively, a light shielding film may be provided on a mask plate transparent to the vicinity of the exit surface without directly contacting the microlens 64a. The second aperture array 68 is formed by, for example, forming a light shielding film made of, for example, chromium on a transparent support member made of quartz glass, with a hole.

<Main beam and unnecessary light>

As described above, in the image exposure apparatus of the present embodiment, the side lobe generated around the main beam condensed by the microlens is one cause of degrading the sharpness of the exposed image. The side lobe is generated not only by the optical system aberration upstream of the microlens including the optical modulation element, but also by the presence of the microlens aperture itself. Hereinafter, a process of generating a side lobe due to the micro lens opening and a method for alleviating the side lobe will be described.

In the case where the opening shape of the first aperture array 66 is a simple shape (for example, a circular shape), the light intensity distribution near the focal position of the microlens 64a indicated by R in FIG. 6 (A) The opening shape of the first aperture array 66 as shown in FIG. 6 (B) is Fourier-transformed. At this time, unnecessary light (side lobe Bb) having a smaller intensity than the main beam Ba is generated around the main beam Ba (center) having a strong light intensity.

There are various cases such as the case where the opening shape of the first aperture array 66 is rectangular except for the example shown in Fig. 6, but in either case, the light intensity distribution near the focal position of the microlens 64a is the first The opening shape of the opening array 66 is Fourier transformed. The positional relationship and the intensity ratio between the main beam Ba and the side lobes Bb are normally set such that the aperture size of the first aperture array 66 and the focal length of the microlens 64a and the wavelength of the laser beam B When it is determined, it is determined unilaterally.

13 and 14, the relationship between the aperture shape of the first aperture array 66 and the light intensity on the focal plane of the microlenses 64a will be described.

V (ξ, η) = 1 (inside of aperture, no shielding) and V (ξ, η) as a function representing the shape of the first aperture array 66 as shown in FIG. 13, the intensity of light at the focal plane (x, y) of the microlens 64a is 0 (outside of the aperture, shielding) Fourier transform.

At this time, if the opening shape of the first opening array 66 is circular, the above Equation 1 can be simplified. (R) = 1 (| R | <Rmax) and V (R) = 0 (| Rmax) when the distance from the z axis (optical axis) of the opening surface of the microlens 64a is R and the radius of the opening is Rmax. R | > Rmax) and letting the light intensity be | U (r) | 2 at a distance r from the z axis in the focal plane of the microlens 64a (= the second aperture array 68) Is expressed by Equation (2).

Here, as shown in Fig. 14, a case will be considered in which n aperture shapes of the aperture shape Rmax and the top ring shape are provided on the opening surface of the microlens 64a as in the present embodiment. When the transmittance at Rm-1? R? Rm is Tm (constant), the light intensity of the focal plane is expressed by Equation 3.

By appropriately setting the values of {R1 ... Rn} (the radius of the diaphragm) and {T1 ... Tn} (transmittance) in this way, the side lobes Bb (unnecessary light) It is possible to move outward from the optical axis (z axis) on the focal plane of the lens 64a, that is, on the second aperture array 68, and unnecessary light can be removed from the second aperture array 68. [ If {T1 ... Tn} is a complex number, it is possible to improve not only the transmittance change but also the side lobe using the effect of changing the phase component of the light.

That is, when the focal distance f of the microlenses 64a is 100 mu m, T1 = 1 (transmission), T2 = 0 (shielding), T3 = 1 (R 2 / f) = 0.1277 (R 2 = 12.77 μm, φ 2 = 25.54 μm) and (R 3 / f) = 0.09535 (radius R1 = 9.535 μm, The sizes of the opening 66a, the light shielding portion 66b and the transmitting portion 66c of the first aperture array 66 are derived as shown in Fig. 5 (0.15 (R3 = 15 占 퐉,? 3 = 30 占 퐉). These numerical values are derived from the above equations and are different from purpose, conditions of establishment, and the like with an optical system having a toric iris existing in the past.

This embodiment is a side lobe relief example due to the micro lens opening. However, the side lobe generated by the axial aberration caused by the optical system upstream of the microlens, for example, the light modulation element such as the DMD, . Rn} (the radius of the diaphragm) and {T1 ... Tn}, it is possible to alleviate the influence of the opening and the influence thereof.

On the other hand, it is preferable to suppress the relative intensity ratio of the side lobe Bb portion to the main beam Ba as much as possible for the following reason. In other words, generally, when exposure is performed to a sensitive photosensitive material (photosensitive material), the photosensitive material is sensitized (blurred) by the side lobe light Bb, and there is a possibility that the effective drawing line width becomes thick (resolution is lowered). Further, at high-definition exposure by an exposure apparatus using a two-dimensional optical modulation element such as the DMD 34, the interval between adjacent drawing beams becomes close to each other, so that the light intensity distribution of the ON beam (at the time of drawing) The influence of the side lobe Bb, which is a factor affecting adjacent drawing lines, can not be ignored.

On the contrary, it is preferable that the opening of the second aperture array 68 provided in the vicinity of the focal position of the microlens array 64 be sufficiently small to leave only the main beam Ba and to remove only the side lobe Bb, It is difficult to remove only the side lobe (Bb) component well for the following reason.

That is, as shown in Fig. 7, there is a fear that the lens optical axis and the center of each opening of the second aperture array 68 are displaced due to manufacturing irregularity in the microlenses 64a. The position of the main beam Ba emitted from each microlens 64a by the manufacturing unevenness of the first imaging optical system 52 and the second imaging optical system 58 (telecentricity non-uniformity) (68). Therefore, the center of the opening of the aperture array 68 and the center of the main beam Ba may be shifted, and the main beam Ba may be narrowed, resulting in a shortage of light quantity.

The side lobes Bb are insufficiently removed by the second aperture array 68 and the aperture diameter of the second aperture array 68 is reduced and the entire laser beam B is excessively narrowed A part of the main beam Ba is also cut off by the second aperture array 68. This causes a problem that intensity deviations occur between the condensed beams of the respective microlenses 64a.

Therefore, in the present embodiment, by providing a mask having an opening shape and a top shape in the first aperture array 66 and narrowing the laser light B, the position of the side lobe Bb at the focal position of the microlens array 64 And the side lobes Bb while leaving the main beam Ba by moving the second aperture array 68 away from the main beam Ba (in the direction away from the optical axis) It is possible to effectively reduce cross-talk between adjoining beams while keeping the imaging line at the time of exposure fine, and to prevent a decrease in light quantity.

The following model description will be made using Figs. 8 to 11. Fig. In this case, the first aperture array 66 is a lens in which the light shielding portion 66b is provided on the lens surface of the microlens array 64 (microlens 64a) with a chrome mask or the like. However, It may be realized by imparting a permeable / semi-permeable coating to the microlenses 64a. Alternatively, the first aperture array 66 may be provided separately in the vicinity of the lens exit surface, instead of directly to the lens exit surface. The structure of the mask introduced here is a typical example, and the number of annular rings of the light-shielding portion 66b described later may be increased.

The relative intensity and positional relationship between the main beam Ba and the side lobe Bb in the vicinity of the focus position of the microlens 64a in the conventional structure as shown in Fig. do. That is, the side lobe Bb exists in a range of about 4 mu m from the center of the main beam Ba, which may cause various problems as described above.

In this embodiment shown in Fig. 9A, the position of the side lobe Bb near the focal point position of the microlens 64a is set to be smaller than that of the micro lens 64a by providing the light shielding portion 66b on the emission side of the microlens 64a .

The light shielding portion 66b is provided with an opening 66a and a top shielding portion 66b in the opening 66a of the first opening array 66. When the opening 66a is circular, In addition, the opening portion 66a and the top-shaped transmitting portion 66c may be further formed in the central portion as shown in Fig. 9 (A). The presence of this transmissive portion 66c is not essential, but it is preferable that the transmissive portion 66c exists in order to make effective use of the light quantity of the laser beam B (main beam Ba).

More specifically, the microlenses 64a are formed of a flat convex lens having a focal length of 100 占 퐉, an opening 66a of? 30 占 퐉, an outer diameter of the light shielding portion 66b of? 25.54 占 퐉, and a diameter of the transmitting portion 66c of? And a laser light having a wavelength (?) = 400 nm was used.

As shown in Figs. 9 to 11, in this model example, the diffraction of the main beam Ba of 4 mu m and the side lobe Bb of the main beam Ba from the center of the main beam Ba to & And the aperture diameter of the second aperture array 68 is made to be 5.6 mu m. With this configuration, even when the center of the main beam Ba and the center of the opening of the second aperture array 66 are shifted by, for example, +/- 0.8 占 퐉 due to the above-described manufacturing unevenness, only the side lobes Bb, It becomes possible to inhibit it in the array 68.

The light intensity distribution of the laser beam B in the arrangement of the microlens 64a, the first aperture array 66 (the opening 66a, and the shielding portion 66b) as shown in Fig. 10 (A) As shown in Fig. 10 (B), before passing through the second aperture array 68, the main beam Ba is about 4 mu m and the side lobe Bb is about 4 mu m, The relative strength is suppressed to about 1/10 as compared with the conventional example shown in Fig. 8 in the range of φ7.2 μm from the center (FIG. 11).

As a result of narrowing the laser beam B having such a light intensity distribution by the second aperture array 68 (? 5.6 m), as shown in Fig. 10 (C) and Fig. 11, The laser beam B having a light intensity distribution which can ignore the side lobe Bb can be obtained.

Since the opening diameter of the second aperture array 68 is? 5.6 占 퐉, while the range in which the intensity of the side lobe Bb is suppressed to about 1/10 of the relative intensity as compared with the conventional example is? 7.2 占 퐉, As described above, the light-converging position caused by the misalignment of the microlens 64a due to the unevenness of the axis, the misalignment of the axis of the second aperture array 68, and the unevenness of the telecentricity due to the manufacturing variation of the first imaging optical system 52 Only the side lobe Bb can be removed with high accuracy from the second aperture array 68 even if there is a deviation of +/- 0.8 mu m.

<Shape of light shield>

In the above embodiment, the case where the opening shape of the first opening array 66 is circular is exemplified. However, the present invention is not limited to this but can be applied to other shapes.

12, when the opening shape of the first aperture array 66 is rectangular, the light-shielding portion 66b also has a rectangular shape, and the light-shielding portion 66b of the side lobe Bb at the focal position of the microlens 64a The position can be moved to a position away from the main beam Ba. Also, when the transmissive portion 66c is provided at the center of the light-shielding portion 66b, the opening shape and topography are also used.

It is not necessary that the light shielding portion 66b completely shield the laser light B and the light shielding portion 66b having a rotationally symmetrical shape has a gradient of gradation (gradation) It may be done. In addition, an element having a predetermined optical density such as an ND filter may be used as the light-shielding portion 66b.

<Others>

Although the embodiments of the present invention have been described above, it is needless to say that the present invention is not limited to the above embodiments, but can be carried out in various forms within the scope not departing from the gist of the present invention.

For example, in the above embodiment, the configuration of the exposure apparatus for exposing with laser light is described as an example, but the present invention is not limited to this, and for example, ordinary visible light or ultraviolet light may be used. Or may be applied to various configurations using spot light, other than the exposure apparatus.

In this embodiment, the DMD 34, which is a reflection type spatial modulation element, is used. Alternatively, a transmissive spatial modulation element using liquid crystal may be used instead.

The disclosure of Japanese Patent Application No. 2012-011050 is hereby incorporated by reference in its entirety. All publications, patent applications, and technical specifications described in this specification are herein incorporated by reference to the same extent as if each individual publication, patent application, and technical specification were specifically and individually stated to be incorporated by reference.

10: Exposure device 14: Moving stage
16: leg 18:
20: Guide 22: Gate
24: scanner 26: sensor
28: exposure head 30: exposure area
34: DMD 52: first imaging optical system
58: Second imaging optical system 64a: Micro lens
64: microlens array 66: first aperture array
66a: opening 66b:
66c: transmissive portion 68: second aperture array
B: laser beam Ba: main beam
Bb: Side lobe P: Photosensitive material

Claims (10)

A microlens array in which microlenses for condensing light modulated by the spatial light modulation device are arrayed; and a plurality of microlenses arranged on the emission side of the microlenses, And a second aperture array provided in the aperture of the first aperture array with the optical axis of the microlens as a center, the aperture shape and the outer shape of the aperture are topical, A microlens array, a mask for shielding light, a transmissive portion which is generally similar to the mask provided at the center of the mask with the optical axis of the microlens as a center, An image-forming optical system, a device for imaging the light condensed by the microlens array on the photosensitive material And a second aperture array in which an aperture for narrowing the light emitted from each of the microlens arrays at the condensing position of the microlens array is arranged. The method according to claim 1,
Wherein the mask is a concentric annular shape centering on the optical axis of the microlens. The method according to claim 1,
Wherein the mask is a concentric rectangle centered on the optical axis of the microlens. 4. The method according to any one of claims 1 to 3,
Wherein the mask and the transmissive portion are composed of an opaque portion and a transparent portion of a film attached to an emission side of the microlens. 4. The method according to any one of claims 1 to 3,
Wherein the mask is a chrome mask formed on the microlens emission side. 6. The method according to any one of claims 1 to 5,
And an outer peripheral portion of the opening portion of the first opening array is an opaque portion. 7. The method according to any one of claims 1 to 6,
Wherein the light source is a semiconductor laser. A lens for condensing light from a light source; a first opening having an opening in the form of an opening for regulating the transmission of light to the emission side of the lens; and a second opening provided in the opening of the first opening around the optical axis of the lens A mask for shielding the light transmitted through the opening and having an opening shape and an outer shape of the opening; a transmissive portion that is generally parallel to the mask provided at the center of the mask with the optical axis of the burr as a center; A second imaging optical system for imaging the light condensed by the lens on the photosensitive material, and a second aperture for arranging an aperture for narrowing the light emitted from the lens at the condensing position of the lens, And an exposure optical system. An exposure apparatus which exposes a predetermined pattern to a photosensitive material using the exposure optical system according to any one of claims 1 to 8. A method for exposing a photosensitive material, which comprises exposing a predetermined pattern to a photosensitive material using the exposure apparatus according to claim 9.

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