JP2003345030A - Exposure device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an exposure device capable of high-speed, unevenness-free exposure. <P>SOLUTION: On the light incidence side of the DMD (Digital Micromirror Device) 50 of an exposure head, a fiber array light source 66, a lens system 67 which corrects and converges the laser light emitted by the fiber array light source 66 on the DMD, and a mirror 69 which reflects the laser light transmitted through the lens system 67 toward the DMD 50 are arranged in this order. The lens system 67 includes a pair of combined lenses 73 (light quantity distribution correction system) which make corrections so that the light quantity distribution of collimated laser light becomes uniform. Hence the DMD 50 is illuminated with the laser light whose light quantity distribution is nearly uniform in a luminous flux cross section. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exposure apparatus,
In particular, it relates to an exposure device that exposes a photosensitive material with a light beam modulated by a spatial light modulator according to image data.

[0002]

2. Description of the Related Art Heretofore, various exposure apparatuses have been proposed which use a spatial light modulator such as a digital micromirror device (DMD) to perform image exposure with a light beam modulated according to image data. . For example, a DMD is a mirror device in which a large number of micromirrors whose reflecting surface angles change according to a control signal are two-dimensionally arranged on a semiconductor substrate such as silicon. An exposure apparatus using this DMD is As shown in FIG. 15A, a light source 1 for irradiating laser light, a lens system 2 for collimating the laser light emitted from the light source 1, and a DM arranged at a substantially focal position of the lens system 2.
It is composed of lens systems 4 and 6 for focusing the laser light reflected by D3 and DMD3 on the scanning surface 5. In this exposure apparatus, a control signal generated according to image data or the like controls on / off of each of the micromirrors of the DMD 3 by a control device (not shown) to modulate laser light, and image exposure is performed with the modulated laser light. There is.

In an exposure apparatus using a spatial light modulation element, surface exposure for simultaneously exposing a region of a predetermined area and line exposure for simultaneously exposing a predetermined line segment are performed, so that high-speed exposure is possible and Exposure in any pattern is possible.

The light source 1 used in the above-mentioned exposure apparatus is, for example, as shown in FIG. 29, a single semiconductor laser 7, a single multimode optical fiber 8 and laser light emitted from the semiconductor laser 7. A plurality of structural units each having a pair of collimating lenses 9 for collimating and coupling to the end face of the multimode optical fiber 8 are arranged, and a plurality of the multimode optical fibers 8 are bundled (bundled) It is composed of.

A laser having an output of about 30 mW (milliwatt) is usually used as the semiconductor laser 7, and a multimode optical fiber 8 having a core diameter of 50 μm, a cladding diameter of 125 μm, and an NA (numerical aperture) of 0.2. Optical fiber is used. Therefore, in order to obtain an output of about 1 W (watt), it is necessary to bundle a total of 48 multi-mode optical fibers 8 of the above-mentioned constitutional unit of 8 × 6, and the diameter of the light emitting point is about 1 mm. Becomes

[0006]

However, in the above-described exposure apparatus, the light source emits laser light whose light amount distribution in the cross section decreases from the central portion to the peripheral portion, and the laser light has an uneven light amount distribution. Since the spatial light modulation element is irradiated with, there is a problem in that exposure unevenness occurs in the areas that are simultaneously exposed. In particular, when exposure is performed at high resolution, image quality is significantly impaired due to uneven exposure. Further, since the light amount distribution is reduced in the peripheral portion, there is a problem that the joint portion is not exposed when the exposure head is made multi.

On the other hand, it is possible to make the light amount distribution uniform by using an optical filter having a low transmittance in the central portion and a high transmittance in the peripheral portion, but in this case, the light amount is lost in the central portion. Become.

The present invention has been made to solve the above problems, and an object of the present invention is to provide an exposure apparatus capable of high-speed and uniform exposure.

[0009]

In order to achieve the above-mentioned object, an exposure apparatus of the present invention comprises a laser device for irradiating a laser beam, and a large number of pixel portions whose light modulation state changes according to a control signal on a substrate. A spatial light modulator which is arranged in a one-dimensional or two-dimensional manner and which modulates the laser light emitted from the laser device, and the laser light which is modulated by each pixel portion of the spatial light modulator is coupled onto the exposure surface. An exposure apparatus comprising: an exposure head including an optical system for forming an image; and a moving means for relatively moving the exposure head with respect to an exposure surface, wherein the exposure apparatus is provided between the laser device and the spatial light modulator. The collimator lens that makes the laser light from the laser device parallel light and the ratio of the light flux width of the peripheral portion to the light flux width of the central portion near the optical axis are smaller on the emission side than on the incident side. Change the luminous flux width at the exit position And a light quantity distribution correction optical system that corrects the light quantity distribution of the laser light collimated by the collimator lens so as to be substantially uniform on the illuminated surface of the spatial modulation element. To do.

In the exposure apparatus of the present invention, the laser light emitted from the laser device of the exposure head to the spatial light modulation element has a large number of pixel portions whose light modulation state changes in accordance with a control signal, one-dimensionally on the substrate. Alternatively, it is modulated by each pixel portion of the spatial light modulator arranged two-dimensionally. The laser light modulated in each pixel portion is imaged on the exposure surface by the optical system. Then, by moving this exposure head relative to the exposure surface by the moving means, the exposure area of a predetermined size moves on the exposure surface, and the exposure surface is exposed at high speed.

In the exposure apparatus of the present invention, a collimator lens and a light quantity distribution correction optical system are arranged between the laser device of the exposure head and the spatial light modulation element. The light beams having the same light flux width in (1) are corrected so that the light flux width in the central portion becomes larger than that in the peripheral portion on the emission side, and conversely, the light flux width in the peripheral portion becomes smaller than that in the central portion. In this way, since the light flux in the central portion can be utilized to the peripheral portion, it is possible to illuminate the spatial modulation element with light having a substantially uniform light amount distribution without lowering the light utilization efficiency as a whole. As a result, exposure unevenness does not occur on the surface to be exposed and high-quality exposure is possible.

In the above-mentioned exposure apparatus, it is preferable that the spatial modulator is arranged so that its longitudinal direction is inclined at a predetermined angle with respect to the direction orthogonal to the moving direction of the exposure head. The interval between the pixel portions of the spatial light modulator becomes narrower, and high-definition exposure becomes possible.

Further, the above-mentioned exposure apparatus may be a multi-head exposure apparatus having a plurality of exposure heads.
As described above, the occurrence of exposure unevenness in the exposure area of a predetermined area is prevented, so that even in the case of using multiple heads, an unexposed area does not occur at the joint.

As the laser device, a device provided with a fiber light source for emitting the laser light incident from the incident end of the optical fiber from its emission end can be used. As this optical fiber, it is preferable to use an optical fiber having a uniform core diameter and a cladding diameter at the exit end smaller than the cladding diameter at the entrance end. The diameter of the light emitting portion of the light source can be reduced, and high brightness can be achieved.

The above-mentioned fiber light source may be, for example, a fiber light source having a structure in which a single semiconductor laser is coupled to the incident end of one optical fiber. However, a plurality of laser lights are combined to form an optical fiber. It is preferable to use a combined laser light source for incidence. High output can be obtained by using a combined laser light source. Also, it is possible to arrange each of the light emitting points at the emission ends of the optical fibers of the plurality of fiber light sources in an array to form a fiber array light source, or to arrange each of the light emitting points in a bundle to form a fiber bundle light source. , When bundled or arrayed in this way,
The number of optical fibers bundled or arrayed to obtain the same light output is small, and the cost is low. Furthermore, since the number of optical fibers is small, the light emitting area when bundled or arrayed is further reduced. That is, the brightness is increased.

The combined laser light source, for example, (1) condenses laser light emitted from each of the plurality of semiconductor lasers, one optical fiber, and each of the plurality of semiconductor lasers, and produces a condensed beam. A configuration including a condensing optical system coupled to an incident end of an optical fiber, (2) a multi-cavity laser having a plurality of light emitting points, one optical fiber, and light emitted from each of the plurality of light emitting points. And a condensing optical system for condensing the condensed laser beam and coupling the condensed beam to the incident end of the optical fiber, or (3) a plurality of multi-cavity lasers, one optical fiber, and A condensing optical system that condenses laser light emitted from each of the plurality of light emitting points of the plurality of multi-cavity lasers and couples the condensing beam to an incident end of the optical fiber. You can

The cladding diameter at the exit end of the optical fiber is preferably smaller than 125 μm, more preferably 80 μm or less, and particularly preferably 60 μm or less, from the viewpoint of reducing the diameter of the light emitting point. An optical fiber with a uniform core diameter and a cladding diameter at the exit end smaller than the cladding diameter at the entrance end is, for example,
It can be configured by coupling a plurality of optical fibers having the same core diameter but different clad diameters. Further, by configuring the plurality of optical fibers to be detachably connected with the connector, replacement becomes easy when the light source module is partially damaged.

As the spatial modulation element, a large number of micromirrors whose reflection surface angles can be changed according to control signals are two-dimensionally arranged on a substrate (for example, a silicon substrate). A device (DMD; Digital Micromirror Device) can be used. Further, the spatial modulation element is configured by arranging a plurality of movable gratings having a ribbon-shaped reflecting surface and movable according to a control signal and fixed gratings having a ribbon-shaped reflecting surface alternately in parallel. One-dimensional grating light valve (GL
V). Further, the spatial modulation element can be configured by a two-dimensional light valve array in which GLVs are arrayed. In addition, a large number of liquid crystal cells capable of blocking transmitted light according to control signals are provided on the substrate.
A liquid crystal shutter array arranged in a dimension may be used.

On the emission side of these spatial modulators, a microlens array provided corresponding to each pixel portion of the spatial modulator and having a microlens for condensing laser light for each pixel is arranged. preferable. When the microlens array is arranged, the laser light modulated by each pixel portion of the spatial modulation element is condensed by each microlens of the microlens array corresponding to each pixel, so that the exposure on the surface to be exposed is performed. Even if the area is enlarged, the size of each beam spot can be reduced, and high-definition exposure can be performed.

Further, in the exposure apparatus of the present invention, in the spatial light modulator, a control is performed in which each of a plurality of pixel units of which the number is smaller than the total number of pixel units arranged on the substrate is generated according to the exposure information. In the case where the control signal is transferred at a control signal transfer rate by controlling by a signal, that is, by controlling a part of the pixel parts without controlling all of the pixel parts arranged on the substrate. It becomes shorter, and the modulation speed of the laser light can be increased. This allows exposure at a higher speed.

Conventionally, a gas laser such as an argon laser or a solid laser by THG (third harmonic) is used as an exposure device (ultraviolet exposure device) for exposing a photosensitive material with laser light in the ultraviolet region. Although it was common, there was a problem that the apparatus was large and maintenance was troublesome, and the exposure speed was slow. The exposure apparatus of the present invention has a laser device with a wavelength of 3
An ultraviolet exposure apparatus can be obtained by using a GaN (gallium nitride) based semiconductor laser of 50 to 450 nm. According to this ultraviolet exposure apparatus, the size and cost of the apparatus can be reduced as compared with the conventional ultraviolet exposure apparatus, and high-speed and high-definition exposure can be performed.

The exposure apparatus of the present invention is an optical modeling apparatus that exposes a photo-curable resin with a light beam to model a three-dimensional model, and a powder is sintered with the light beam to form a sintered layer to form a sintered layer. The present invention can be appropriately applied to a layered modeling apparatus or the like that stacks a bonding layer to model a three-dimensional model made of a powder sintered body.

For example, a modeling tank containing a photo-curable resin, a support table for supporting a modeled object provided in the modeling tank so as to be able to move up and down, a laser device for irradiating laser light,
A large number of pixel portions, each of which has a light modulation state that changes in response to a control signal, are two-dimensionally arranged on a substrate, and a spatial light modulator for modulating the laser light emitted from the laser device and a modulation by each pixel portion. An exposure head including an optical system that forms an image of the generated laser light on the liquid surface of the photocurable resin housed in the modeling tank, and the exposure head moves relative to the liquid surface of the photocurable resin. In a stereolithography apparatus provided with a moving means for moving, between the laser device and the spatial light modulator,
A collimator lens that collimates the laser light from the laser device, and the ratio of the luminous flux width of the peripheral portion to the luminous flux width of the central portion close to the optical axis is smaller on the emission side than on the incident side, A light amount distribution correction optical system that changes the luminous flux width at each emission position, and corrects the light amount distribution of the laser light that is collimated by the collimator lens so that it is substantially uniform on the illuminated surface of the spatial modulation element. By arranging, it becomes possible to perform high-speed and uniform modeling. The specific device configuration is described in Japanese Patent Application No. 2001-274360.

Further, a modeling tank for containing powder that is sintered by light irradiation, a support stand for supporting a modeled object that is vertically movable in the modeling tank, and a laser device for irradiating laser light, respectively. A large number of pixel portions whose light modulation state changes according to a control signal are two-dimensionally arranged on a substrate, and are modulated in each pixel portion and a spatial light modulation element that modulates laser light emitted from the laser device. A stack including an exposure head including an optical system for forming an image of the laser beam on the surface of the powder contained in the modeling tank, and a moving unit that moves the exposure head relative to the surface of the powder. In the modeling device,
Between the laser device and the spatial light modulator, a collimator lens that collimates the laser light from the laser device and a ratio of the light flux width of the peripheral portion to the light flux width of the central portion near the optical axis is incident. The light flux width at each emission position is changed so that the emission side becomes smaller than the emission side, and the light amount distribution of the laser light collimated by the collimator lens is substantially equal on the irradiated surface of the spatial modulation element. By arranging the light amount distribution correction optical system for performing correction so as to be uniform, high-speed and uniform modeling is possible. A specific device configuration is described in Japanese Patent Application No. 2001-274351.

[0025]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. (First Embodiment) [Structure of Exposure Apparatus] As shown in FIG. 1, an exposure apparatus according to an embodiment of the present invention has a flat plate shape for adsorbing and holding a sheet-shaped photosensitive material 150 on its surface. The stage 152 is provided. On the upper surface of the thick plate-shaped installation base 156 supported by the four leg portions 154, 2 extending along the stage moving direction is provided.
A book guide 158 is installed. Stage 152
Is arranged such that its longitudinal direction faces the stage moving direction, and is supported by a guide 158 so as to be capable of reciprocating. In addition, this exposure apparatus includes a stage 15
A drive device (not shown) for driving the guide 2 along the guide 158 is provided.

The stage 15 is provided at the center of the installation table 156.
A U-shaped gate 160 is provided so as to straddle the two movement paths. Each of the ends of the U-shaped gate 160 is fixed to both side surfaces of the installation table 156. This gate 16
A scanner 162 is provided on one side across 0, and a plurality of (for example, two) detection sensors 164 for detecting the leading end and the trailing end of the photosensitive material 150 are provided on the other side. The scanner 162 and the detection sensor 164 have the gate 16
0, and is fixedly arranged above the moving path of the stage 152. The scanner 162 and the detection sensor 164 are connected to a controller (not shown) that controls them.

As shown in FIGS. 2 and 3B, the scanner 162 includes a plurality of (eg, 14) exposure heads arranged in a matrix of m rows and n columns (eg, 3 rows and 5 columns). 166 is provided. In this example, the photosensitive material 150
The four exposure heads 166 are arranged in the third row in relation to the width of the. When the individual exposure heads arranged in the m-th row and the n-th column are shown, they are referred to as exposure heads 166 _mn .

Exposure area 168 by exposure head 166
Is a rectangular shape having a short side in the sub-scanning direction. Therefore, as the stage 152 moves, a belt-shaped exposed region 170 is formed on the photosensitive material 150 for each exposure head 166. In the case of indicating the exposure area by the individual exposure heads arranged in the m-th row and the n-th column, the exposure area 168 _mn
It is written as.

As shown in FIGS. 3A and 3B,
In addition, the strip-shaped exposed area 170 is orthogonal to the sub-scanning direction.
Each row arranged in a line so that they are lined up with no gap in the direction
Each of the exposure heads of the
A natural number times the long side of A, twice in this embodiment)
It is arranged. Therefore, the exposure area 168 of the first row
₁₁And exposure area 168₁₂The part that cannot be exposed between
Second row exposure area 168_{twenty one}And exposure area 16 on the 3rd row
8₃₁It can be exposed by.

Each of the exposure heads 166 _{11 to} 166 _mn , as shown in FIGS. 4, 5A and 5B, is a spatial light modulator that modulates an incident light beam for each pixel in accordance with image data. A digital micromirror device (DMD) 50 is provided as an element. The DMD 50 is connected to a controller (not shown) including a data processing unit and a mirror drive control unit. The data processing unit of this controller generates a control signal for driving and controlling each micromirror in the region to be controlled by the DMD 50 for each exposure head 166 based on the input image data. The area to be controlled will be described later. The mirror drive control unit controls the angle of the reflecting surface of each micro mirror of the DMD 50 for each exposure head 166 based on the control signal generated by the image data processing unit. The control of the angle of the reflecting surface will be described later.

On the light incident side of the DMD 50, there is provided a fiber array light source having a laser emitting portion in which the emitting ends (light emitting points) of the optical fibers are arranged in a line along the direction corresponding to the long side direction of the exposure area 168. 66, fiber array light source 66
The lens system 67 that corrects the laser light emitted from the lens and focuses it on the DMD, and the laser light that has passed through the lens system 67 is D
A mirror 69 that reflects toward the MD 50 is arranged in this order.

The lens system 67 is a fiber array light source 66.
A pair of combination lenses 71 for collimating the laser light emitted from the laser beam, a pair of combination lenses 73 for correcting the light amount distribution of the collimated laser light to be uniform, and a light amount distribution are corrected. It is composed of a condenser lens 75 for condensing the laser light on the DMD. With respect to the arrangement direction of the laser emission ends, the combined lens 73 expands the light beam in a portion near the optical axis of the lens and contracts the light beam in a portion away from the optical axis.
Further, it has a function of allowing light to pass as it is in the direction orthogonal to the arrangement direction, and corrects the laser light so that the light amount distribution becomes uniform.

This light quantity distribution correction optical system adjusts the light beam width at each emission position such that the ratio of the light beam width at the peripheral portion to the light beam width at the central portion near the optical axis is smaller on the emission side than on the incident side. When the parallel light flux from the light source is changed to irradiate the DMD, the light amount distribution on the irradiated surface is corrected to be substantially uniform. The operation of this light quantity distribution correction optical system will be described below.

First, as shown in FIG. 25A, the entire luminous flux width (total luminous flux width) H of the incident luminous flux and the outgoing luminous flux.
A case where 0 and H1 are the same will be described. Note that, in FIG. 25A, the portions indicated by reference numerals 51 and 52 are
2 is a view virtually showing an entrance surface and an exit surface in a light quantity distribution correction optical system.

In the light quantity distribution correcting optical system, it is assumed that the luminous fluxes incident on the central portion near the optical axis Z1 and the luminous flux incident on the peripheral portions have the same luminous flux widths h0 and h1 (h0 = hl). ). The light amount distribution correction optical system expands the luminous flux width h0 of the central incident light flux with respect to the light having the same luminous flux width h0 and h1 on the incident side, and conversely with respect to the peripheral incident light flux. As a result, the light beam width h1 is reduced. That is, regarding the width h10 of the emitted light flux at the central portion and the width h11 of the emitted light flux at the peripheral portion,
Make sure that h11 <h10. Expressed by the ratio of the luminous flux width, the ratio “h11 / h10” of the luminous flux width of the peripheral portion to the luminous flux width of the central portion on the emission side is the ratio (h11 / h10) on the incident side.
It is smaller than (1 / h0 = 1) ((h11 /
h10) <1).

By changing the luminous flux width in this manner, the luminous flux in the central portion where the light amount distribution is normally large can be utilized to the peripheral portion where the light amount is insufficient,
As a whole, the light amount distribution on the irradiated surface is made substantially uniform without lowering the light use efficiency. The degree of homogenization is, for example,
The light amount unevenness in the effective area is set to be within 30%, preferably within 20%.

The operation and effect of such a light quantity distribution correcting optical system is the same when the entire luminous flux width is changed between the incident side and the outgoing side (FIGS. 25B and 25C).

FIG. 25B shows the total luminous flux width H on the incident side.
When 0 is “reduced” to the width H2 and emitted (H0> H
2) is shown. Even in such a case, the light amount distribution correction optical system has the same light flux widths h0 and h on the incident side.
The light having a value of 1 is changed to a luminous flux width h1 at the central portion on the emission side.
0 is made larger than that in the peripheral portion, and conversely, the luminous flux width h11 in the peripheral portion is made smaller than that in the central portion. Considering the reduction ratio of the luminous flux, the reduction ratio of the incident light flux at the central portion is made smaller than that of the peripheral portion, and the reduction ratio of the incident light flux at the peripheral portion is made larger than that of the central portion. Also in this case, the ratio “H11 / H10” of the luminous flux width of the peripheral portion to the luminous flux width of the central portion is
It is smaller than (1 / h0 = 1) ((h11 / h1
0) <1).

FIG. 25C shows the entire luminous flux width H on the incident side.
When 0 is “expanded” to the width Η3 and emitted (H0 <H
3) is shown. Even in such a case, the light amount distribution correction optical system has the same light flux widths h0 and h on the incident side.
The light having a value of 1 is changed to a luminous flux width h1 at the central portion on the emission side.
0 is made larger than that in the peripheral portion, and conversely, the luminous flux width h11 in the peripheral portion is made smaller than that in the central portion. Considering the expansion ratio of the light flux, the expansion ratio for the incident light flux at the central portion is made larger than that at the peripheral portion, and the expansion ratio for the incident light flux at the peripheral portion is made smaller than at the central portion. Also in this case, the ratio “h11 / h10” of the luminous flux width of the peripheral portion to the luminous flux width of the central portion is equal to the ratio (h11 / h10) on the incident side.
It is smaller than (1 / h0 = 1) ((h11 / h1
0) <1).

In this way, the light quantity distribution correcting optical system changes the luminous flux width at each emission position, and the ratio of the luminous flux width of the peripheral portion to the luminous flux width of the central portion near the optical axis Z1 is compared with that on the incident side. Since the light flux with the same luminous flux width on the incident side has a larger luminous flux width on the exit side, the luminous flux width at the central portion is larger than that at the peripheral portion, and the luminous flux width at the peripheral portion is smaller than that at the central portion. Will be smaller than. This makes it possible to utilize the light flux in the central portion to the peripheral portion, and to form a light flux cross section with a substantially uniform light amount distribution without reducing the light utilization efficiency of the optical system as a whole.

Next, an example of specific lens data of a pair of combination lenses used as a light amount distribution correcting optical system will be shown. This example shows lens data when the light amount distribution in the cross section of the emitted light flux is a Gaussian distribution, as in the case where the light source is a laser array light source. When one semiconductor laser is connected to the incident end of the single mode optical fiber, the light quantity distribution of the light flux emitted from the optical fiber becomes a Gaussian distribution. The present embodiment can be applied to such a case. Further, the present invention is also applicable to the case where the amount of light in the central portion close to the optical axis is larger than the amount of light in the peripheral portion by reducing the core diameter of the multimode optical fiber to approach the configuration of the single mode optical fiber.

Table 1 below shows basic lens data.

[0043]

[Table 1]

As can be seen from Table 1, the pair of compound lenses is composed of two rotationally symmetric aspherical lenses. When the surface on the light incident side of the first lens arranged on the light incident side is the first surface and the surface on the light emitting side is the second surface, the first surface has an aspherical shape. When the surface on the light incident side of the second lens arranged on the light emitting side is the third surface and the surface on the light emitting side is the fourth surface, the fourth surface has an aspherical shape.

In Table 1, the surface number Si is the i-th (i =
1 to 4), the radius of curvature ri represents the radius of curvature of the i-th surface, and the surface distance di represents the surface distance between the i-th surface and the (i + 1) th surface on the optical axis. The unit of the surface distance di value is millimeter (mm). The refractive index Ni represents the value of the refractive index for the wavelength 405 nm of the optical element having the i-th surface.

Table 2 below shows aspherical surface data of the first and fourth surfaces.

[0047]

[Table 2]

The above-mentioned aspherical surface data is represented by the coefficient in the following expression (A) representing the aspherical surface shape.

[0049]

[Equation 1]

In the above equation (A), each coefficient is defined as follows. Z: The length (mm) of a perpendicular line drawn from a point on the aspherical surface located at a height ρ from the optical axis to the tangent plane (the plane perpendicular to the optical axis) at the apex of the aspherical surface ρ: From the optical axis Distance (mm) K: Cone coefficient C: Paraxial curvature (1 / r, r: Paraxial radius of curvature) ai: Aspheric coefficient of the i-th order (i = 3 to 10) Symbol in the values shown in Table 2 "E" indicates that the number following it is a "base index" with a base of 10. The number represented by an exponential function with a base of 10 is multiplied by the number before "E". Indicates that For example,
If "1.0E-02", it means "1.0 × 10 ^-2 ".

FIG. 27 shows the light quantity distribution of the illumination light obtained by the pair of combination lenses shown in Tables 1 and 2. The horizontal axis shows the coordinates from the optical axis, and the vertical axis shows the light amount ratio (%). For comparison, FIG. 26 shows a light amount distribution (Gaussian distribution) of illumination light when no correction is performed. As can be seen from FIGS. 26 and 27, by performing the correction with the light amount distribution correction optical system, a substantially uniform light amount distribution is obtained as compared with the case where the correction is not performed. As a result, it is possible to perform uniform exposure with a uniform laser beam without reducing the light utilization efficiency of the exposure head. The laser light from the light quantity distribution correction optical system 73 is a light flux with good parallelism, and a long focal depth can be realized by irradiating this light on the DMD to form an image.

On the light reflecting side of the DMD 50, the DMD 50
Lens systems 54 and 58 for arranging the laser light reflected by 50 on the scanning surface (exposed surface) 56 of the photosensitive material 150 are arranged. The lens systems 54 and 58 are arranged so that the DMD 50 and the exposed surface 56 have a conjugate relationship.

The DMD 50, as shown in FIG.
A micro mirror (micro mirror) 62 is disposed on an M cell (memory cell) 60 while being supported by a support, and a large number (for example, 6
(00 × 800) micromirrors arranged in a grid pattern. Each pixel is provided with a micro mirror 62 supported by a column at the top, and a material having a high reflectance such as aluminum is vapor-deposited on the surface of the micro mirror 62. The reflectance of the micro mirror 62 is 90% or more. Immediately below the micro mirror 62, a silicon gate CMOS SRAM cell 60 manufactured in a normal semiconductor memory manufacturing line is arranged via a pillar including a hinge and a yoke, and the whole is monolithic (integrated type). ) Is configured.

When a digital signal is written in the SRAM cell 60 of the DMD 50, the micromirror 62 supported by the supporting column is ± α degrees (for example, ± 10 degrees) with respect to the substrate side on which the DMD 50 is arranged with the diagonal line as the center. Tilt in range. FIG. 7A shows a state in which the micro mirror 62 is in the ON state and is inclined to + α degrees, and FIG. 7B shows a state in which the micro mirror 62 is in the OFF state and is inclined to −α degrees. Therefore, by controlling the inclination of the micro mirror 62 in each pixel of the DMD 50 according to the image signal as shown in FIG. 6, the light incident on the DMD 50 is reflected in the inclination direction of each micro mirror 62. .

FIG. 6 shows an example of a state in which a part of the DMD 50 is enlarged and the micromirror 62 is controlled to + α degree or −α degree. Each micro mirror 6
The on / off control of No. 2 is performed by a controller (not shown) connected to the DMD 50. A light absorber (not shown) is arranged in the direction in which the light beam is reflected by the micro mirror 62 in the off state.

Further, it is preferable that the DMD 50 is disposed so as to be slightly inclined such that its short side makes a predetermined angle θ (for example, 1 ° to 5 °) with the sub-scanning direction. 8 (A) is D
8 shows scanning trajectories of the reflected light image (exposure beam) 53 by each micromirror when the MD 50 is not tilted, and FIG.
(B) is the exposure beam 53 when the DMD 50 is tilted
The scanning locus of is shown.

In the DMD 50, a large number (for example, 600 sets) of micromirror rows, in which a large number (for example, 800) of micromirrors are arranged in the longitudinal direction, are arranged in the lateral direction. As shown in B), by tilting the DMD 50, the pitch P ₁ of the scanning locus (scanning line) of the exposure beam 53 by each micromirror is set to the DMD.
The pitch is narrower than the scanning line pitch P ₂ when 50 is not tilted, and the resolution can be greatly improved. on the other hand,
Since the tilt angle of the DMD 50 is small, the scan width W ₂ when the DMD 50 is tilted and the scan width W ₁ when the DMD 50 is not tilted are substantially the same.

Further, the same scanning line is overlaid and exposed (multiple exposure) by different micromirror rows.
By performing multiple exposure in this way, it is possible to control a very small amount of the exposure position and realize high-definition exposure. Further, the joint between the plurality of exposure heads arranged in the main scanning direction can be connected without a step by controlling the exposure position with a very small amount.

Instead of tilting the DMD 50,
The same effect can be obtained by arranging the micromirror rows in a zigzag pattern with a predetermined gap in the direction orthogonal to the sub-scanning direction.

As shown in FIG. 9A, the fiber array light source 66 includes a plurality (for example, six) of laser modules 64, and each laser module 64 has one end of the multimode optical fiber 30. Are combined. At the other end of the multimode optical fiber 30, an optical fiber 31 having the same core diameter as the multimode optical fiber 30 and a cladding diameter smaller than the multimode optical fiber 30 is coupled, and as shown in FIG. The laser emitting portion 68 is configured by arranging the emitting ends (light emitting points) of the optical fibers 31 in one line along the main scanning direction orthogonal to the sub scanning direction. As shown in FIG. 9D, the light emitting points can be arranged in two rows along the main scanning direction.

The exit end of the optical fiber 31 is shown in FIG.
As shown in FIG. 7, the support plate 65 is sandwiched and fixed by two support plates 65 having flat surfaces. A transparent protective plate 63 such as glass is arranged on the light emitting side of the optical fiber 31 to protect the end face of the optical fiber 31. Protection plate 63
May be arranged in close contact with the end face of the optical fiber 31, or may be arranged so that the end face of the optical fiber 31 is sealed. Although the emission end of the optical fiber 31 has a high light density and easily collects dust and easily deteriorates, by disposing the protective plate 63, it is possible to prevent dust from adhering to the end face and delay the deterioration.

In this example, since the emitting ends of the optical fibers 31 having a small clad diameter are arranged in a row without a gap, the multimode optical fibers 30 are adjacent to each other in the portion having a large clad diameter. The fibers 30 are stacked, and the output end of the optical fiber 31 coupled to the stacked multi-mode optical fibers 30 is two of the optical fibers 31 coupled to two multi-mode optical fibers 30 adjacent to each other in a portion having a large cladding diameter. It is arranged so as to be sandwiched between two emission ends.

Such an optical fiber is shown in FIG.
As shown in FIG. 3, the length of the multimode optical fiber 30 having a large cladding diameter is
It can be obtained by coaxially coupling optical fibers 31 having a small clad diameter of cm. The two optical fibers are fused and coupled so that the incident end face of the optical fiber 31 is connected to the emitting end face of the multimode optical fiber 30 so that the central axes of the both optical fibers coincide with each other. As described above, the diameter of the core 31a of the optical fiber 31 is the same as the diameter of the core 30a of the multimode optical fiber 30.

Further, a short optical fiber obtained by fusing an optical fiber having a small clad diameter with an optical fiber having a short clad diameter is coupled to the emitting end of the multimode optical fiber 30 via a ferrule or an optical connector. You may.
By detachably coupling with a connector or the like, the tip portion can be easily replaced when the optical fiber having a small clad diameter is damaged, and the cost required for maintenance of the exposure head can be reduced. In the following, the optical fiber 31
May be referred to as the exit end of the multimode optical fiber 30.

As the multimode optical fiber 30 and the optical fiber 31, a step index type optical fiber,
Either a graded index type optical fiber or a composite type optical fiber may be used. For example, a step index type optical fiber manufactured by Mitsubishi Cable Industries, Ltd. can be used. In the present embodiment, the multimode optical fiber 30 and the optical fiber 31 are step index type optical fibers, and the multimode optical fiber 30 has a cladding diameter = 125 μm, a core diameter = 25 μm, and NA = 0.
2, the transmittance of the incident end face coat = 99.5% or more,
The optical fiber 31 has a clad diameter of 60 μm and a core diameter of 2
5 μm, NA = 0.2.

In general, with laser light in the infrared region, the propagation loss increases when the cladding diameter of the optical fiber is reduced.
Therefore, a suitable cladding diameter is determined according to the wavelength band of laser light. However, the shorter the wavelength is, the smaller the propagation loss becomes, and in the laser light having a wavelength of 405 nm emitted from the GaN-based semiconductor laser, the cladding thickness {(clad diameter-core diameter) / 2} is the infrared light in the wavelength band of 800 nm. Of about 1/2 when propagating infrared light, and about 1 when propagating infrared light in the wavelength band of 1.5 μm for communication.
Even at / 4, the propagation loss hardly increases. Therefore, the cladding diameter can be reduced to 60 μm.

However, the cladding diameter of the optical fiber 31 is 60
It is not limited to μm. The clad diameter of the optical fiber used in the conventional fiber light source is 125 μm,
Since the depth of focus becomes deeper as the cladding diameter becomes smaller, the cladding diameter of the multimode optical fiber is preferably 80 μm or less, more preferably 60 μm or less, and 40 μm.
The following are more preferable. On the other hand, the core diameter is at least 3-4
Since the μm is required, the cladding diameter of the optical fiber 31 is preferably 10 μm or more.

The laser module 64 is composed of a combined laser light source (fiber light source) shown in FIG. This combined laser light source is a plurality (eg, 7) of chip-shaped lateral multimode or single mode GaN-based semiconductor lasers L arranged and fixed on the heat block 10.
D1, LD2, LD3, LD4, LD5, LD6 and LD7, and collimator lenses 11, 12 and 1 provided corresponding to each of the GaN-based semiconductor lasers LD1 to LD7.
It comprises 3, 14, 15, 16, and 17, one condenser lens 20, and one multimode optical fiber 30. The number of semiconductor lasers is not limited to seven. Cladding diameter = 60μm, Core diameter = 50μ
20 for a multimode optical fiber with m and NA = 0.2
As many semiconductor laser beams as possible can be incident, the required amount of light of the exposure head can be realized, and the number of optical fibers can be further reduced.

The GaN semiconductor lasers LD1 to LD7 are
The oscillation wavelengths are all common (for example, 405 nm), and the maximum outputs are also all common (for example, 1 for a multimode laser).
00 mW, and 30 mW for a single mode laser). The GaN-based semiconductor lasers LD1 to LD7 have a wavelength range of 350 nm to 450 nm and the above 40
A laser having an oscillation wavelength other than 5 nm may be used.

The above combined laser light source is shown in FIGS.
As shown in FIG. 3, it is housed together with other optical elements in a box-shaped package 40 having an upper opening. The package 40 includes a package lid 41 formed so as to close the opening thereof, and introduces a sealing gas after the degassing process,
By closing the opening of the package 40 with the package lid 41, the combined laser light source is hermetically sealed in the closed space (sealing space) formed by the package 40 and the package lid 41.

A base plate 42 is fixed to the bottom surface of the package 40, and the heat block 10, the condenser lens holder 45 for holding the condenser lens 20, and the multimode light are provided on the upper surface of the base plate 42. A fiber holder 46 that holds the entrance end of the fiber 30 is attached. The exit end of the multimode optical fiber 30 is
It is pulled out from the package through an opening formed in the wall surface of the package 40.

A collimator lens holder 44 is attached to the side surface of the heat block 10 and holds the collimator lenses 11 to 17. An opening is formed on the lateral wall surface of the package 40 and G
A wiring 47 for supplying a drive current to the aN semiconductor lasers LD1 to LD7 is drawn out of the package.

In FIG. 13, in order to avoid complication of the drawing, GaN among a plurality of GaN-based semiconductor lasers is used.
Only the system semiconductor laser LD7 is numbered, and only the collimator lens 17 of the plurality of collimator lenses is numbered.

FIG. 14 shows the collimator lenses 11-1.
7 is a front view of a mounting portion of No. 7. Each of the collimator lenses 11 to 17 is formed in a shape in which a region including the optical axis of a circular lens having an aspherical surface is elongated and cut out in parallel planes. The elongated collimator lens can be formed by molding resin or optical glass, for example. The length direction of the collimator lenses 11 to 17 is a GaN-based semiconductor laser LD1.
~ LD7 is closely arranged in the arrangement direction of the light emitting points so as to be orthogonal to the arrangement direction of the light emitting points (the horizontal direction in FIG. 14).

On the other hand, GaN semiconductor lasers LD1 to LD
7 includes an active layer having an emission width of 2 μm, and the divergence angle in the direction parallel to the active layer and the divergence angle in the direction perpendicular to the active layer are, for example, 10
Lasers which emit laser beams B1 to B7 in the respective states of 30 ° and 30 ° are used. These GaN-based semiconductor lasers LD1 to LD7 have an emission point of 1 in the direction parallel to the active layer.
It is arranged so as to line up in a row.

Therefore, the laser beams B1 to B7 emitted from the respective light emitting points diverge with respect to the elongated collimator lenses 11 to 17 as described above, in which the direction with a large divergence angle coincides with the length direction. The light enters in a state in which the direction with a small angle coincides with the width direction (direction orthogonal to the length direction). That is, each collimator lens 11 to 17 has a width of 1.1 mm and a length of 4.6 mm, and the laser beams B1 to B7 incident on them have horizontal and vertical beam diameters of 0.9 mm and 2. It is 6 mm. Also,
Each of the collimator lenses 11 to 17 has a focal length f ₁ =
3 mm, NA = 0.6, lens arrangement pitch = 1.25 m
m.

The condenser lens 20 is formed by cutting a region including the optical axis of a circular lens having an aspherical surface into long and thin parallel planes and arranging the collimator lenses 11 to 17 in the arrangement direction, that is, in the horizontal direction and in a direction perpendicular to it. It has a short shape. This condenser lens 20 has a focal length f ₂ = 23 m
m, NA = 0.2. The condenser lens 20 is also formed by molding resin or optical glass, for example.

[Operation of Exposure Apparatus] Next, the operation of the exposure apparatus will be described.

In each exposure head 166 of the scanner 162, the laser beams B1, B2, B3, B emitted in a diverging state from each of the GaN semiconductor lasers LD1 to LD7 constituting the combined laser light source of the fiber array light source 66.
4, B5, B6, and B7 are collimated by the corresponding collimator lenses 11 to 17, respectively. The collimated laser beams B1 to B7 are condensed by the condenser lens 20, and the core 30 of the multimode optical fiber 30 is collected.
It converges on the incident end face of a.

In this example, the collimator lenses 11 to 17 and the condenser lens 20 constitute a condenser optical system, and the condenser optical system and the multimode optical fiber 30 constitute a multiplexing optical system. That is, the laser beams B1 to B7 condensed by the condenser lens 20 as described above.
From the optical fiber 31 which is incident on the core 30a of the multimode optical fiber 30, propagates in the optical fiber, is combined with one laser beam B, and is coupled to the emission end of the multimode optical fiber 30. Emit.

In each laser module, the coupling efficiency of the laser beams B1 to B7 to the multimode optical fiber 30 is 0.85, and the GaN semiconductor lasers LD1 to LD7 are used.
Output of 30 mW, the output of each of the optical fibers 31 arranged in an array is 180 mW (= 3
A combined laser beam B of 0 mW × 0.85 × 7) can be obtained. Therefore, the output of the laser emitting section 68 in which the six optical fibers 31 are arranged in an array is about 1 W (= 1
80 mW x 6).

Laser emitting section 6 of fiber array light source 66
As shown in FIG. 8, high-luminance light emitting points are arranged in a line in the main scanning direction. Since the conventional fiber light source that combines the laser light from a single semiconductor laser into one optical fiber has a low output, a desired output could not be obtained without arranging in multiple rows. Since the combined laser light source used in the mode has a high output, a desired output can be obtained even with a small number of rows, for example, one row.

For example, in a conventional fiber light source in which a semiconductor laser and an optical fiber are coupled one-to-one, a laser having an output of about 30 mW (milliwatt) is usually used as the semiconductor laser and a core diameter of 50 μm is used as the optical fiber. Since a multimode optical fiber with a cladding diameter of 125 μm and an NA (numerical aperture) of 0.2 is used, 48 multimode optical fibers (8 × 6) are required to obtain an output of about 1 W (watt). The area of the light emitting area is 0.62 mm ² (0.675 mm × 0.925 m)
m), the brightness at the laser emitting portion 68 is 1.6 ×
10 ⁶ (W / m ² ), the brightness per optical fiber is 3.2
It is × 10 ⁶ (W / m ² ).

On the other hand, in the present embodiment, as described above, an output of about 1 W can be obtained with the six multimode optical fibers, and the area of the light emitting region at the laser emitting portion 68 is 0.0081 mm ² ( 0.325 mm x 0.025 m
m), the brightness at the laser emitting portion 68 is 123 ×
Since it is 10 ⁶ (W / m ² ), it is possible to increase the brightness by about 80 times as compared with the conventional one. The brightness per optical fiber is 90 × 10 ⁶ (W / m ² ), which is about 28
The brightness can be doubled.

Now, with reference to FIGS. 15A and 15B, the difference in depth of focus between the conventional exposure head and the exposure head of the present embodiment will be described. The diameter of the light emitting region of the bundle-shaped fiber light source of the conventional exposure head in the sub scanning direction is 0.675 mm, and the diameter of the light emitting region of the fiber array light source of the exposure head of the present embodiment in the sub scanning direction is 0.075 mm.
It is 25 mm. As shown in FIG. 15A, in the conventional exposure head, since the light emitting area of the light source (bundle-shaped fiber light source) 1 is large, the angle of the light beam incident on the DMD 3 is large, and as a result, it is incident on the scanning surface 5. The angle of the luminous flux becomes large. For this reason, the beam diameter tends to be thicker in the focusing direction (shift in the focusing direction).

On the other hand, as shown in FIG. 15B, in the exposure head of this embodiment, since the diameter of the light emitting area of the fiber array light source 66 in the sub-scanning direction is small, it passes through the lens system 67 to the DMD 50. The angle of the incident light beam becomes smaller, and as a result, the angle of the light beam incident on the scanning surface 56 becomes smaller. That is, the depth of focus becomes deep. In this example, the diameter of the light emitting area in the sub-scanning direction is about 30 times that of the conventional one.
It is possible to obtain a depth of focus corresponding to the diffraction limit. Therefore, it is suitable for exposure of a minute spot. The effect on the depth of focus is more remarkable and effective as the required light amount of the exposure head is larger. In this example, 1 projected on the exposure surface
The pixel size is 10 μm × 10 μm. DMD
Is a reflection type spatial modulation element, but FIGS. 15A and 15B are developed views for explaining the optical relationship.

The image data corresponding to the exposure pattern is DM
It is input to a controller (not shown) connected to D50 and is temporarily stored in a frame memory in the controller. This image data is data in which the density of each pixel forming the image is represented by a binary value (whether or not dots are recorded).

The stage 152 having the photosensitive material 150 adsorbed on its surface is moved at a constant speed from the upstream side of the gate 160 to the downstream side along the guide 158 by a driving device (not shown). When the stage 152 passes under the gate 160, the detection sensor 164 attached to the gate 160
When the leading edge of the photosensitive material 150 is detected by, the image data stored in the frame memory is sequentially read out for each of a plurality of lines, and each exposure head 166 is controlled based on the image data read by the data processing unit. A signal is generated. Then, the mirror drive controller controls on / off of each of the micromirrors of the DMD 50 for each exposure head 166 based on the generated control signal.

The laser light emitted from the fiber array light source 66 is collimated by the combination lens 71 and corrected by the combination lens 73 so that the light amount distribution on the illuminated surface of the DMD 50 becomes substantially uniform. It is condensed on the DMD 50 by 75. When the DMD 50 is irradiated with laser light, the laser light reflected when the micromirror of the DMD 50 is in the on state is imaged on the exposed surface 56 of the photosensitive material 150 by the lens systems 54 and 58. In this way, the laser light emitted from the fiber array light source 66 is turned on and off for each pixel, and the photosensitive material 150 is D
Exposure is performed in pixel units (exposure area 168) that are substantially the same as the number of pixels used in MD50. Further, by moving the photosensitive material 150 together with the stage 152 at a constant speed, the photosensitive material 150 is sub-scanned by the scanner 162 in the direction opposite to the stage moving direction, and the strip-shaped exposed area 170 is formed for each exposure head 166. It is formed.

As shown in FIGS. 16A and 16B, in this embodiment, the DMD 50 has 600 micromirror rows in which 800 micromirrors are arrayed in the main scanning direction, in the subscanning direction. Although arranged, some micromirror rows (for example, 800 × 10
It can be controlled so that only the 0th column) is driven.

As shown in FIG. 16 (A), a micromirror array arranged at the center of the DMD 50 may be used, or as shown in FIG. 16 (B), a micromirror array arranged at the end of the DMD 50. Mirror rows may be used. Further, when a defect occurs in some of the micromirrors, the micromirror array used may be appropriately changed depending on the situation, such as using a micromirror array in which no defect has occurred.

The data processing speed of the DMD 50 is limited, and the modulation speed per line is determined in proportion to the number of pixels used. Therefore, by using only a part of micromirror rows, The modulation speed becomes faster. on the other hand,
In the case of the exposure method in which the exposure head is continuously moved relative to the exposure surface, it is not necessary to use all the pixels in the sub-scanning direction.

For example, in the case of using only 300 of the 600 sets of micromirror arrays, the modulation can be performed twice as fast per line as compared with the case of using all of the 600 sets. Also, of the 600 pairs of micromirrors,
When only 200 sets are used, modulation can be performed three times faster per line than when all 600 sets are used. That is, an area of 500 mm in the sub-scanning direction can be exposed in 17 seconds. Furthermore, when using only 100 pairs,
Modulation can be performed 6 times faster per line. That is, an area of 500 mm in the sub scanning direction can be exposed in 9 seconds.

The number of micromirror rows used, that is, the number of micromirrors arranged in the sub-scanning direction is preferably 10 or more and 200 or less, and 10 or more and 100 or more.
The following is more preferable. Since the area per micromirror corresponding to one pixel is 15 μm × 15 μm, DM
Converted to the usage area of D50, 12 mm x 150 μm
It is preferable that the area is not less than 12 mm × 3 mm and not less than 1
A region of 2 mm × 150 μm or more and 12 mm × 1.5 mm or less is more preferable.

If the number of micromirror rows used is within the above range, as shown in FIGS. 17A and 17B, the laser light emitted from the fiber array light source 66 is converted into substantially parallel light by the lens system 67. Then, the DMD 50 can be irradiated. It is preferable that the irradiation area where the DMD 50 irradiates the laser light coincides with the usage area of the DMD 50.
If the irradiation area is wider than the usage area, the utilization efficiency of the laser light is reduced.

On the other hand, the diameter of the light beam focused on the DMD 50 in the sub-scanning direction needs to be reduced in accordance with the number of micro mirrors arranged in the sub-scanning direction by the lens system 67. If the number of rows is less than 10, the angle of the light beam incident on the DMD 50 becomes large and the depth of focus of the light beam on the scanning surface 56 becomes shallow, which is not preferable. Further, it is preferable that the number of micromirror rows used is 200 or less from the viewpoint of modulation speed. In addition,
The DMD is a reflective spatial light modulator, which is shown in FIG.
(B) is a developed view for explaining the optical relationship.

When the sub-scanning of the photosensitive material 150 by the scanner 162 is completed and the rear end of the photosensitive material 150 is detected by the detection sensor 164, the stage 152 moves the gate 160 along the guide 158 by a driving device (not shown). After returning to the origin on the most upstream side, the gate 160 is again moved along the guide 158 from the upstream side to the downstream side at a constant speed.

As described above, since the exposure apparatus of this embodiment uses the spatial modulation element, high speed exposure with an arbitrary pattern is possible. Further, since the spatial modulation element is illuminated with light having a substantially uniform light amount distribution using the light amount distribution correction optical system, it is possible to perform exposure without unevenness on the exposed surface.

The exposure apparatus of the present embodiment is equipped with an exposure head that illuminates the spatial light modulator with a fiber array light source in which the emission ends (light emitting points) of the optical fibers of the combined laser light source are arranged in an array. ing. In this fiber array light source, the clad diameter at the emitting end of the optical fiber is made smaller than the clad diameter at the incident end, so that the diameter of the light emitting portion becomes smaller and the brightness of the fiber array light source can be increased. Thereby, it is possible to realize an exposure head and an exposure apparatus having a deep depth of focus.

For example, a beam diameter of 1 μm or less and a resolution of 0.
Even in the case of ultra-high resolution exposure of 1 μm or less, a deep depth of focus can be obtained, and high-speed and high-definition exposure becomes possible. Therefore, the exposure apparatus of the present embodiment can be used also in the exposure process of a thin film transistor (TFT) which requires high resolution.

Further, since the combined laser light source for combining a plurality of laser lights and making them enter the optical fiber is used, the output at the exit end of the optical fiber becomes large, and exposure at a high output is possible. Become. Furthermore, since the output of each fiber light source increases, the number of fiber light sources required to obtain a desired output decreases, and the cost of the exposure apparatus can be reduced.

Further, the exposure apparatus of the present embodiment is provided with a DMD in which 600 sets of micro mirror rows in which 800 micro mirrors are arranged in the main scanning direction and 600 sets in the sub scanning direction are arranged. Since control is performed so that only some of the micromirror rows are driven, the modulation speed per line is faster than when all the micromirror rows are driven. This enables high-speed exposure.

(Second Embodiment) An exposure apparatus according to the second embodiment is a grating light valve (GLV) as a spatial light modulator used in each exposure head.
Is used. GLV is described, for example, in US Pat.
311 and 360, as disclosed in
It is a type of (Micro Electro Mechanical Systems) type spatial light modulator (SLM; Spacial Light Modulator), and is a reflective diffraction grating type spatial light modulator. Since the other points are the same as those of the exposure apparatus according to the first embodiment, description thereof will be omitted.

Each of the exposure heads 166 _{11 to} 166 _mn , as shown in FIGS. 30, 31 (A) and 31 (B), is a spatial light modulator that modulates an incident light beam for each pixel according to image data. As an element, a shape that is long in a predetermined direction (line shape)
The GLV 300 having the above structure is provided, and the fiber array light source 66, the lens system 67, and the mirror 69 are arranged in this order on the light incident side of the GLV 300, as in the first embodiment.

The longitudinal direction of the line-shaped GLV 300 is parallel to the arrangement direction of the optical fibers of the fiber array light source 66, and the reflection surface of the ribbon-shaped microbridge of the GLV 300 is substantially parallel to the reflection surface of the mirror 69. And is connected to a controller (not shown) that controls this.

As shown in FIG. 32, in the GLV 300, a large number of microbridges 209 (for example, 6480) having ribbon-shaped reflecting surfaces are arranged in parallel on a long substrate 203 made of silicon or the like. A plurality of slits 211 are provided between adjacent microbridges 209.
Are formed. Usually, one pixel has a plurality of pixels (for example, 6 pixels).
209 rows of micro bridges, 1
Assuming that the pixel is composed of a row of 6 microbridges, an exposure of 1080 pixels is possible with 6480 microbridges.

Each microbridge 209 is shown in FIG.
As shown in (A) and (B), silicon nitride (SiN
The reflective electrode film 209b made of a single-layer metal film of aluminum (or gold, silver, copper, etc.) is formed on the surface of the flexible beam 209a made of x) or the like. Reflective electrode film 209
Each of b is connected to a power source via a switch (not shown) by a wire (not shown).

Here, the operating principle of the GLV 300 will be briefly described. The microbridge 209 is separated from the substrate 203 by a predetermined distance when no voltage is applied. However, when a voltage is applied between the microbridge 209 and the substrate 203, the microbridge 209 is separated from the microbridge 209 by electrostatically induced charges. An electrostatic attraction force is generated between the substrate 203 and the substrate 203, and the microbridge 209 bends toward the substrate 203 side. Then, when the application of the voltage is stopped, the bending is eliminated, and the microbridge 209 is separated from the substrate 203 by the elastic return. Therefore, by alternately arranging the microbridges to which the voltage is applied and the microbridges to which the voltage is not applied, it is possible to form the diffraction grating by applying the voltage.

FIG. 33A shows a case where no voltage is applied to the microbridge array in pixel units and the microbridge array is in an off state. In the off state, the micro bridge 209
The heights of the reflecting surfaces are uniform and the reflected light is specularly reflected without any optical path difference. That is, only the 0th order diffracted light can be obtained. On the other hand, FIG. 33B shows a case where a voltage is applied to the pixel-based microbridge array and the microbridge array is in the ON state. The voltage is applied to every other microbridge 209. In the ON state, the central portion of the microbridge 209 bends according to the above-described principle, and reflective surfaces having steps are formed alternately. That is, a diffraction grating is formed. When laser light is incident on this reflecting surface, an optical path difference is generated between the light reflected by the flexible microbridge 209 and the light reflected by the non-flexible microbridge 209.
The ± first-order diffracted light is emitted in a predetermined direction.

Therefore, the controller (not shown)
By controlling the driving of the microbridge array in each pixel of the GLV 300 by turning on / off the applied voltage according to the control signal, the laser light incident on the GLV 300 is modulated for each pixel and diffracted in a predetermined direction. It

On the light reflection side of the GLV 300, that is, on the side where the diffracted light (0th order diffracted light and ± 1st order diffracted light) is emitted, a lens for focusing the diffracted light on the scanning surface (exposed surface) 56. The systems 54 and 58 are arranged so that the GLV 300 and the exposed surface 56 have a conjugate relationship. Further, in order that the diffracted light enters the lens system 54, the GLV 300 is arranged with its ribbon-shaped reflecting surface preliminarily inclined with respect to the optical axis of the lens system 54 by a predetermined angle (for example, 45 °).

In FIGS. 31A and 31B, the 0th-order diffracted light is shown by a dotted line and the ± 1st-order diffracted light is shown by a solid line. It is focused only in the longitudinal direction. Therefore, between the lens system 54 and the lens system 58, the elongated shield plate 5 for excluding the 0th-order diffracted light from the optical path to the scanning surface 56.
7 are arranged so that the longitudinal direction thereof is orthogonal to the longitudinal direction of the GLV 300.

The lens system 54 makes the incident diffracted light GL
The light is condensed in the longitudinal direction of V300 and is made parallel light in the sub-scanning direction. At the focus position of the 0th-order diffracted light between the lens system 54 and the lens system 58, a long shield plate 55 for excluding the 0th-order diffracted light from the optical path to the scanning surface 56 has a longitudinal direction of G.
It is arranged so as to be orthogonal to the longitudinal direction of the LV. As a result, only the 0th order diffracted light is selectively excluded.

In this exposure head, when image data according to the exposure pattern is input to a controller (not shown) connected to the GLV 300, a control signal is generated based on this image data, and based on the generated control signal. Thus, each of the microbridges of the GLV 300 is ON / OFF-controlled for each pixel for each exposure head. As a result, the photosensitive material 150 is exposed in pixel units of substantially the same number as the number of pixels of the GLV 300, and a band-shaped exposed region is formed for each exposure head by sub-scanning by the movement of the stage 152.

In the exposure apparatus of this embodiment, the GLV30
Since 0 is a long spatial light modulator having a narrow width in the short side direction, it is difficult to illuminate efficiently, but as described in the first embodiment, the light source for illuminating the GLV is combined. Since a high-brightness fiber array light source in which the emitting ends of the optical fibers of the laser light source are arranged in an array is used and the cladding diameter at the emitting end of the optical fiber is made smaller than the cladding diameter at the incident end, the laser emitting portion The diameter of the beam emitted from 68 in the sub-scanning direction becomes smaller, and the angle of the light beam that passes through the lens system 67 and the like and enters the GLV 300 becomes smaller. This makes it possible to efficiently illuminate the GLV 300 and obtain a deep depth of focus. Further, since the combined laser light source is used, it is possible to perform exposure with high output, and the cost of the exposure apparatus can be reduced.

Next, a modified example of the above-described exposure apparatus will be described. [Application of exposure apparatus] The above-described exposure apparatus is used, for example, for a dry film resist (DFR; Dry) in a manufacturing process of a printed wiring board (PWB).
Suitable for exposure of film resist, formation of color filter in liquid crystal display (LCD) manufacturing process, exposure of DFR in manufacturing process of TFT, exposure of DFR in manufacturing process of plasma display panel (PDP), etc. Can be used for.

Further, the above-mentioned exposure apparatus can be used for various laser processing such as laser ablation, sintering, and lithography for removing a part of a material by vaporizing, scattering, etc. by laser irradiation. The above-described exposure apparatus has a high output and can perform exposure at a high speed and a long focal depth, and thus can be used for fine processing such as laser ablation. For example, the exposure apparatus described above may be used to form a PWB by removing a resist according to a pattern by ablation instead of performing a development process, or to form a PWB pattern by direct ablation without using a resist. it can. In addition, a groove width of several tens of μm in a lab-on-chip in which mixing, reaction, separation, detection, etc. of many solutions are integrated on glass or plastic chips.
It can also be used for the formation of microchannels.

In particular, the above-mentioned exposure apparatus uses the GaN-based semiconductor laser for the fiber array light source, and therefore can be suitably used for the above-mentioned laser processing. That is, Ga
The N-based semiconductor laser can be driven by a short pulse, and can obtain sufficient power for laser ablation and the like. Further, since it is a semiconductor laser, it can be driven at high speed at a repetition frequency of about 10 MHz, and can perform high-speed exposure, unlike a solid-state laser having a low driving speed. Furthermore,
Since metal has a large light absorptance of laser light near a wavelength of 400 nm and is easily converted into heat energy, laser ablation or the like can be performed at high speed.

When exposing a liquid resist used for patterning a TFT or a liquid resist used for patterning a color filter, in order to eliminate sensitivity deterioration (desensitization) due to oxygen inhibition, a nitrogen atmosphere is used. It is preferable to expose the material to be exposed below. By exposing in a nitrogen atmosphere, oxygen inhibition of the photopolymerization reaction is suppressed, the resist has high sensitivity, and high-speed exposure is possible.

Further, in the above-mentioned exposure apparatus, both a photon mode photosensitive material in which information is directly recorded by exposure and a heat mode photosensitive material in which information is recorded by heat generated by exposure can be used. When using a photon mode photosensitive material, a GaN-based semiconductor laser, a wavelength conversion solid-state laser, or the like is used for the laser device, and when using a heat mode photosensitive material, the laser device is an AlGaAs-based semiconductor laser (infrared laser), A solid state laser is used.

[Other Spatial Modulator] In the above-described first embodiment, an example in which the DMD micromirror is partially driven has been described, but the length in the direction corresponding to the predetermined direction is the same as the predetermined direction. A long and narrow DM in which a large number of micromirrors whose reflection surfaces can be changed according to control signals are two-dimensionally arranged on a substrate longer than the length in the intersecting direction.
Even if D is used, the number of micromirrors that control the angle of the reflecting surface is reduced, so that the modulation speed can be similarly increased.

In the above-described first and second embodiments, the exposure head provided with the DMD or GLV as the spatial modulation element has been described.
Mechanical Systems) type spatial modulator (SLM;
Spacial Light Modulator), an optical element (PLZT element) that modulates transmitted light by an electro-optical effect, a liquid crystal light shutter (FLC), and other spatial modulation elements other than the MEMS type are also used. By using a part of the pixel parts for all the pixel parts, it is possible to increase the modulation speed per pixel and one main scanning line.
The same effect can be obtained.

Incidentally, the MEMS is a general term for a micro system in which micro size sensors, actuators, and control circuits are integrated by the micro machining technology based on the IC manufacturing process, and the MEMS type spatial modulator is It means a spatial modulation element driven by electromechanical operation using electrostatic force.

[Other Exposure Methods] As shown in FIG. 18, the entire surface of the photosensitive material 150 may be exposed by one scan in the X direction by the scanner 162 as in the above-described embodiment. 19 (A) and (B), the scanner 1
After the photosensitive material 150 is scanned in the X direction by 62, the scanner 162 is moved in the Y direction by one step and the scanning is performed in the X direction. The entire surface may be exposed. In this example, the scanner 162 has 18 exposure heads 166.

[Other Laser Device (Light Source)] In the above embodiment, an example of using a fiber array light source provided with a plurality of combined laser light sources has been described, but the laser device is an array of combined laser light sources. It is not limited to the fiber array light source. For example, it is possible to use a fiber array light source that is an array of fiber light sources provided with one optical fiber that emits laser light incident from a single semiconductor laser having one light emitting point.

Further, in the above embodiment, as shown in FIG. 20, a plurality of (for example,
Although an example of using a combined laser light source provided with a laser array in which seven (7) chip-shaped semiconductor lasers LD1 to LD7 are arranged has been described, the combined laser light source is a laser emitted from a plurality of chip-shaped semiconductor lasers. It is not limited to those that combine lights.

A plurality (for example, 5) shown in FIG.
There is known a chip-shaped multi-cavity laser 110 in which individual light emitting points 110a are arranged in a predetermined direction. For example, as shown in FIG. 22, a combined laser light source including this multi-cavity laser 110 can be used.
This combined laser light source is a multi-cavity laser 110.
And a single multimode optical fiber 130 and a condenser lens 120. The multi-cavity laser 110 has, for example, a G having an oscillation wavelength of 405 nm.
It can be composed of an aN laser diode.

In the multi-cavity laser 110, the light emitting points can be arranged with high positional accuracy as compared with the case where chip-shaped semiconductor lasers are arranged, and therefore the laser beams emitted from the respective light emitting points are easily combined. However, as the number of light emitting points increases, the multi-cavity laser 110 is likely to bend during laser manufacturing. Therefore, the number of light emitting points 110a is preferably 5 or less.

In the above structure, each of the laser beams B emitted from each of the plurality of light emitting points 110a of the multi-cavity laser 110 is condensed by the condenser lens 120 and is incident on the core 130a of the multimode optical fiber 130. . The laser light incident on the core 130a propagates in the optical fiber, is combined into one, and is emitted.

A plurality of light emitting points 110a of the multi-cavity laser 110 are arranged side by side within a width substantially equal to the core diameter of the multi-mode optical fiber 130, and the condenser lens 1 is provided.
As 20, a convex lens having a focal length substantially equal to the core diameter of the multimode optical fiber 130, or a rod lens for collimating the emitted beam from the multicavity laser 110 only in a plane perpendicular to its active layer is used.
The coupling efficiency of the laser beam B to the multimode optical fiber 130 can be increased.

Further, as shown in FIG. 21B, a plurality of multicavity lasers 1 are provided on the heat block 100.
Using a multi-cavity laser array in which 10 are arranged in the same direction as the light emitting points 110a of each chip, as shown in FIG. 23, a plurality of (for example, nine) multi-cavity lasers 110 are arranged on the heat block 111. A combined laser light source including the laser arrays 140 arranged at equal intervals can be configured. The plurality of multi-cavity lasers 110 are arranged and fixed in the same direction as the light emitting points 110a of each chip.

This combined laser light source comprises a laser array 14
0, a plurality of lens arrays 114 arranged corresponding to each multi-capability laser 110, and a laser array 14
It is configured to include one rod lens 113 arranged between 0 and a plurality of lens arrays 114, one multimode optical fiber 130, and a condenser lens 120. The lens array 114 includes a plurality of microlenses corresponding to the light emitting points of the multicapability laser 110.

In the above configuration, each of the laser beams B emitted from each of the plurality of light emitting points 10a of the plurality of multi-cavity lasers 110 is condensed in a predetermined direction by the rod lens 113, and then the laser beam of the lens array 114 is collected. The light is collimated by each microlens. The collimated laser beam L is condensed by the condenser lens 120 and is incident on the core 130 a of the multimode optical fiber 130.
The laser light that has entered the core 130a propagates in the optical fiber, is combined into one, and is emitted.

An example of still another combined laser light source will be shown. In this combined laser light source, as shown in FIGS. 24A and 24B, a heat block 182 having an L-shaped cross section in the optical axis direction is mounted on a heat block 180 having a substantially rectangular shape, and two heats are provided. A storage space is formed between the blocks. On the upper surface of the L-shaped heat block 182, a plurality of (for example, 2) light emitting points (for example, 5) are arranged in an array.
The individual multi-cavity lasers 110 are arranged and fixed at equal intervals in the same direction as the arrangement direction of the light emitting points 110a of each chip.

A concave portion is formed in the substantially rectangular heat block 180, and a plurality of light emitting points (for example, five) are arranged in an array on the space-side upper surface of the heat block 180 (for example, five). The (two) multi-cavity lasers 110 are arranged such that their light emitting points are located on the same vertical plane as the light emitting points of the laser chips arranged on the upper surface of the heat block 182.

On the laser beam emitting side of the multi-cavity laser 110, a collimating lens array 18 in which collimating lenses are arranged corresponding to the light emitting points 110a of each chip.
4 are arranged. Collimating lens array 184
Is so that the length direction of each collimator lens and the direction where the divergence angle of the laser beam is large (fast axis direction) match, and the width direction of each collimator lens matches the direction where the divergence angle is small (slow axis direction). It is arranged. As described above, by integrating the collimator lenses in an array, the space utilization efficiency of laser light is improved, the output of the combined laser light source is increased, and the number of parts is reduced and the cost can be reduced. .

On the laser beam emitting side of the collimator lens array 184, one multimode optical fiber 13 is provided.
0 and a condenser lens 120 that condenses and combines the laser beam at the incident end of the multimode optical fiber 130.

With the above arrangement, the laser block 180,
Multiple multi-cavity lasers 1 arranged on 182
Each of the laser beams B emitted from each of the ten emission points 10a is collimated by the collimator lens array 184 and condensed by the condenser lens 120,
The light enters the core 130a of the multimode optical fiber 130. The laser light that has entered the core 130a propagates in the optical fiber, is combined into one, and is emitted.

As described above, this combined laser light source can achieve a particularly high output by arranging multi-cavity lasers in multiple stages and forming an array of collimator lenses. By using this combined laser light source, a fiber array light source or a bundle fiber light source with higher brightness can be formed, and thus it is particularly suitable as a fiber light source forming the laser light source of the exposure apparatus of the present invention.

Incidentally, it is possible to construct a laser module in which each of the above-mentioned combined laser light sources is housed in a casing and the emission end of the multimode optical fiber 130 is pulled out from the casing.

Further, in the above embodiment, another optical fiber having the same core diameter as the multimode optical fiber and a cladding diameter smaller than the multimode optical fiber is provided at the exit end of the multimode optical fiber of the combined laser light source. Although an example in which the fiber diameter of the fiber array light source is increased by combining the above has been described, for example, the cladding diameter is 125 μm, 80 μm, 6
A multimode optical fiber such as 0 μm may be used without coupling another optical fiber to the output end.

[Other Imaging Optical System] In the first embodiment described above, two sets of lenses are arranged as an imaging optical system on the light reflecting side of the DMD used in the exposure head, but laser light is used. An image forming optical system for forming an enlarged image may be arranged. DMD
By enlarging the cross-sectional area of the light flux line reflected by, the exposure area area (image area) on the exposed surface can be enlarged to a desired size.

For example, as shown in FIG. 28A, the exposure head DMD 50, the illumination device 144 for irradiating the DMD 50 with the laser light, and the lens system 454 for enlarging the laser light reflected by the DMD 50 to form an image. 458, DMD50
, A microlens array 472 in which a large number of microlenses 474 are arranged corresponding to the respective pixels, an aperture array 476 in which a large number of apertures 478 are provided corresponding to the respective microlenses of the microlens array 472, and a laser which has passed through the apertures. It can be configured with lens systems 480 and 482 that image light on the exposed surface 56.

In this exposure head, when laser light is emitted from the illumination device 144, the cross-sectional areas of the light flux lines reflected in the ON direction by the DMD 50 are changed to the lens systems 454 and 458.
Is enlarged several times (for example, twice). The magnified laser light is condensed by each microlens of the microlens array 472 corresponding to each pixel of the DMD 50,
It passes through the corresponding apertures in aperture array 476. The laser light that has passed through the aperture is reflected by the lens system 48.
An image is formed on the exposed surface 56 by 0 and 482.

In this imaging optical system, the laser light reflected by the DMD 50 is magnified several times by the magnifying lenses 454 and 458 and projected onto the exposed surface 56, so that the entire image area is widened. At this time, if the microlens array 472 and the aperture array 476 are not arranged, as shown in FIG. 28B, one pixel size (spot size) of each beam spot BS projected on the exposed surface 56 is exposed. The MTF becomes larger according to the size of the area 468 and represents the sharpness of the exposure area 468.
(Modulation Transfer Function) characteristics deteriorate.

On the other hand, when the microlens array 472 and the aperture array 476 are arranged, the DMD 50
The laser light reflected by the microlens array 4
The microlenses 72 collect light corresponding to the pixels of the DMD 50. As a result, as shown in FIG. 28C, even if the exposure area is enlarged, the spot size of each beam spot BS is set to a desired size (for example, 1).
It is possible to reduce the size to 0 μm × 10 μm), prevent deterioration of MTF characteristics, and perform high-definition exposure. The exposure area 468 is tilted because the DMD 50 is tilted in order to eliminate a gap between pixels.

Further, even if the beam is thickened by the aberration of the microlens, the beam can be shaped by the aperture so that the spot size on the exposed surface 56 becomes a constant size, and at the same time, each pixel can be shaped. Crosstalk between adjacent pixels can be prevented by passing through the aperture provided correspondingly.

Further, by using a high-intensity light source for the illumination device 144 as in the above embodiment, the lens 458 can be obtained.
Since the angle of the light flux incident on each microlens of the microlens array 472 becomes small, it is possible to prevent a part of the light flux of the adjacent pixel from entering. That is, a high extinction ratio can be realized.

[Application Example] The exposure apparatus of the present invention is an optical modeling apparatus that exposes a photocurable resin with a light beam to model a three-dimensional model, and a powder is sintered with the light beam to form a sintered layer. The present invention can be appropriately applied to a layered modeling apparatus or the like that stacks the sintered layers to model a three-dimensional model made of a powder sintered body.

For example, FIG. 34 shows the structure of an optical modeling apparatus to which the present invention is applied. This stereolithography apparatus includes a container 556 that opens upward, and a liquid photo-curable resin 550 is stored in the container 556. Further, in the container 556, a flat plate-shaped lifting stage 552 is arranged,
The lift stage 552 is supported by a support portion 554 arranged outside the container 556. The support portion 554 is provided with a male screw portion 554A.
A lead screw 555, which is rotatable by a drive motor (not shown), is screwed into A. As the lead screw 555 rotates, the elevating stage 552 moves up and down.

Photocurable resin 5 contained in container 556
A box-shaped scanner 562 is arranged above the liquid surface of 52 with its longitudinal direction oriented in the lateral direction of the container 556.
The scanner 562 is supported by two support arms 560 attached to both side surfaces in the lateral direction. In addition,
The scanner 562 has the same configuration as the scanner of the above-described embodiment, includes a plurality of exposure heads, and is connected to a controller (not shown) that controls the exposure heads.

Guides 558 extending in the sub-scanning direction are provided on both side surfaces in the longitudinal direction of the container 556. The lower ends of the two support arms 560 are attached to the guide 558 so as to be capable of reciprocating along the sub-scanning direction. In addition, the support arm 56 is included in this stereolithography apparatus.
A drive device (not shown) is provided for driving the scanner 562 along with the guide 558 together with the zero.

In this optical modeling apparatus, the scanner 562 is
A driving device (not shown) moves the guide 558 from the upstream side to the downstream side in the sub-scanning direction at a constant speed. By moving the scanner 562 at a constant speed, the liquid surface of the photocurable resin 550 is scanned, and a strip-shaped cured region is formed for each exposure head. When one layer of curing is completed by one sub-scanning by the scanner 562, the scanner 5
62 is returned to the origin located on the most upstream side along the guide 558 by a driving device (not shown). Next, the lead screw 555 is rotated by a drive motor (not shown) to lower the elevating stage 552 by a predetermined amount, and the photocurable resin 5
The cured portion of 50 is submerged below the liquid surface, and the upper portion of the cured portion is filled with a liquid photocurable resin 550. Then, the sub-scanning by the scanner 562 is performed again. In this way, exposure (curing) by sub-scanning and stage lowering are repeated,
The three-dimensional model is formed by stacking the cured parts. By using the high-intensity laser device of the present invention for the exposure head of the scanner 562, a deep depth of focus can be obtained and high-speed and high-definition modeling can be performed.

[0154]

According to the exposure apparatus of the present invention, it is possible to perform exposure at high speed without unevenness.

[Brief description of drawings]

FIG. 1 is a perspective view showing an appearance of an exposure apparatus according to a first embodiment.

FIG. 2 is a perspective view showing a configuration of a scanner of the exposure apparatus according to the first embodiment.

FIG. 3A is a plan view showing an exposed area formed on a photosensitive material, and FIG. 3B is a view showing an arrangement of exposure areas by each exposure head.

FIG. 4 is a perspective view showing a schematic configuration of an exposure head of the exposure apparatus according to the first embodiment.

5A is a cross-sectional view taken along the optical axis in the sub-scanning direction, showing the configuration of the exposure head shown in FIG. 4, and FIG.
FIG.

FIG. 6 is a partially enlarged view showing the configuration of a digital micromirror device (DMD).

FIGS. 7A and 7B are explanatory diagrams for explaining the operation of the DMD.

FIGS. 8A and 8B are plan views showing the arrangement of the exposure beam and the scanning line in comparison between the case where the DMD is not tilted and the case where the DMD is tilted.

9A is a perspective view showing a configuration of a fiber array light source, FIG. 9B is a partially enlarged view of FIG. 9A, and FIGS. 9C and 9D show an array of light emitting points in a laser emitting portion. It is a top view shown.

FIG. 10 is a diagram showing a configuration of a multimode optical fiber.

FIG. 11 is a plan view showing a configuration of a combined laser light source.

FIG. 12 is a plan view showing the configuration of a laser module.

13 is a side view showing the configuration of the laser module shown in FIG.

FIG. 14 is a partial side view showing the configuration of the laser module shown in FIG.

15A and 15B are cross-sectional views along the optical axis showing the difference between the depth of focus in the conventional exposure apparatus and the depth of focus in the exposure apparatus according to the first embodiment.

16A and 16B are diagrams showing an example of a DMD usage area;

FIG. 17A is a side view when the DMD usage area is appropriate, and FIG. 17B is a cross-sectional view in the sub-scanning direction along the optical axis of FIG.

FIG. 18 is a plan view for explaining an exposure method in which a photosensitive material is exposed by one scanning with a scanner.

19A and 19B are plan views for explaining an exposure system in which a photosensitive material is exposed by scanning a scanner a plurality of times.

FIG. 20 is a perspective view showing a configuration of a laser array.

21A is a perspective view showing a configuration of a multi-cavity laser, and FIG. 21B is a perspective view of a multi-cavity laser array in which the multi-cavity lasers shown in FIG.

FIG. 22 is a plan view showing another configuration of the combined laser light source.

FIG. 23 is a plan view showing another configuration of the combined laser light source.

24A is a plan view showing another configuration of the combined laser light source, and FIG. 24B is a sectional view taken along the optical axis of FIG.

FIG. 25 is an explanatory diagram of a concept of correction by a light amount distribution correction optical system.

FIG. 26 is a graph showing a light amount distribution when the light source has a Gaussian distribution and the light amount distribution is not corrected.

FIG. 27 is a graph showing a light quantity distribution after correction by a light quantity distribution correction optical system.

FIG. 28A is a sectional view taken along the optical axis showing the configuration of another exposure head having a different coupling optical system, and FIG. 28B is projected onto the exposed surface when a microlens array or the like is not used. FIG. 6C is a plan view showing a light image that is projected, and FIG. 6C is a plan view showing a light image that is projected onto the exposed surface when a microlens array or the like is used.

FIG. 29 is a sectional view taken along the optical axis showing the configuration of a conventional fiber light source.

FIG. 30 is a perspective view showing a schematic configuration of an exposure head of the exposure apparatus according to the second embodiment.

31A is a sectional view taken along the optical axis showing the configuration of the exposure head shown in FIG. 30, and FIG. 31B is a side view of FIG.

Figure 32: Grating light valve (GLV)
3 is a partially enlarged view showing the configuration of FIG.

33A and 33B are explanatory diagrams for explaining the operation of the GLV.

FIG. 34 is a perspective view showing an example in which the present invention is applied to a stereolithography apparatus.

[Explanation of symbols]

LD1 to LD7 GaN semiconductor laser 10 heat block 11-17 Collimator lens 20 Condensing lens 30 multimode optical fiber 50 Digital Micromirror Device (DMD) 53 Reflected light image (exposure beam) 54, 58 lens system 56 Scanning surface (exposed surface) 64 laser module 66 Fiber array light source 68 Laser emission part 73 Combination lens 150 photosensitive materials 152 stages 162 scanner 166 exposure head 168 exposure area 170 Exposed area

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Yoji Okazaki             798 Miyadai, Kaisei-cho, Ashigarakami-gun, Kanagawa Prefecture             Shishi Film Co., Ltd. (72) Inventor Kazuhiko Nagano             798 Miyadai, Kaisei-cho, Ashigarakami-gun, Kanagawa Prefecture             Shishi Film Co., Ltd. (72) Inventor Takeshi Fujii             798 Miyadai, Kaisei-cho, Ashigarakami-gun, Kanagawa Prefecture             Shishi Film Co., Ltd. (72) Inventor Hiromitsu Yamakawa             1-324 Uetakecho, Saitama City, Saitama Prefecture             Fuji Photo Optical Co., Ltd. F-term (reference) 2H052 BA02 BA09 BA12                 2H097 AA03 CA17 LA09 LA10                 5F046 BA07 CA03 CB14 CB18 CB27

Claims (5)

[Claims] 1. A laser device for irradiating laser light, and a large number of pixel portions each of which has a light modulation state that changes in response to a control signal are arranged in a one-dimensional or two-dimensional manner on a substrate, and are irradiated from the laser device. An exposure head including a spatial light modulator that modulates laser light, and an optical system that forms an image of the laser light modulated by each pixel portion of the spatial light modulator on the exposure surface, and the exposure head with respect to the exposure surface. A moving means for relatively moving the laser device, and a collimator lens for collimating laser light from the laser device into parallel light between the laser device and the spatial light modulator, and an optical axis The light flux width at each exit position was changed so that the ratio of the light flux width at the peripheral portion to the light flux width at the closer central portion was smaller on the exit side than on the incident side, and collimated by the collimator lens. Laser light The amount distribution, exposure apparatus characterized by a light intensity distribution correcting optical system for correcting to become substantially uniform, are located in the illuminated surface of the spatial modulator. 2. The exposure apparatus according to claim 1, wherein the spatial modulator is arranged so that its longitudinal direction is inclined at a predetermined angle with respect to a direction orthogonal to the moving direction of the exposure head. 3. The spatial modulation element is composed of a micromirror device in which a large number of micromirrors whose reflecting surface angles can be changed according to control signals are two-dimensionally arranged on a substrate. The exposure apparatus according to Item 1 or 2. 4. A large number of the spatial modulation elements, which are arranged alternately in parallel, each including a movable grating having a ribbon-shaped reflecting surface and movable according to a control signal, and a fixed grating having a ribbon-shaped reflecting surface. The exposure apparatus according to claim 1 or 2, wherein the exposure apparatus is configured by a grating light valve configured as described above. 5. The exposure apparatus according to claim 1, further comprising a plurality of the exposure heads.