WO2006090575A1

WO2006090575A1 - Exposing method and aligner

Info

Publication number: WO2006090575A1
Application number: PCT/JP2006/302028
Authority: WO
Inventors: Norihisa Takada; Tomoya Kitagawa
Original assignee: Fujifilm Corporation
Priority date: 2005-02-22
Filing date: 2006-02-07
Publication date: 2006-08-31
Also published as: JP2006234960A

Abstract

The center (C56) of a variation range (D56) of a surface (56) to be exposed is brought close to the central value (C166) of the focal point adjusting range of an exposure head (166) by driving an elevator (157) provided on an installation base (156) to move a stage (152) in the Z direction, i.e. the direction of optical axis. Consequently, the center (C56) of the variation range (D56) of the surface (56) to be exposed due to meandering of a photosensitive material (150) or error in thickness dimension approaches the value (C166) and a focal point is adjusted by an autofocus mechanism in each exposure head (166). The value (C166) is the central position of a focal point adjusting range of each exposure head (166), and when the center (C56) of variation range (D56) on the surface of the photosensitive material (150), i.e. the surface (56) to be exposed, is brought close to the value (C166), the variation range (D56) of the surface (56) to be exposed due to meandering of the photosensitive material (150) or error in thickness dimension error can be confined easily within a range (D166), i.e. the focal point adjusting range of each exposure head (166). As a result, occurrence of error and lowering of yield can be prevented.

Description

Specification

Exposure method and exposure apparatus

Technical field

The present invention relates to an exposure method and an exposure apparatus, and more particularly to an exposure method and an exposure apparatus that expose a photosensitive material with a light beam modulated by a spatial modulation element or the like according to image information.

Background art

Conventionally, an exposure apparatus that uses a spatial light modulator (SLM) such as a digital micromirror device (DMD) to perform image exposure with a light beam modulated in accordance with image data (image information) Various proposals have been made!

[0003] For example, the DMD is a mirror device that is two-dimensionally arranged on a semiconductor substrate such as a silicon substrate such as silicon that has a large number of micromirrors whose reflection surface changes according to a control signal. In the exposure apparatus 300 of the conventional digital scanning exposure method (maskless exposure method) shown in FIG. 10, a light source for irradiating laser light, a lens system for collimating the irradiated laser light, and a substantially focal position of the lens system. DMD micromirrors using control signals generated in accordance with image data, etc., by an exposure head (scanner) 302 having a DMD arranged in the lens and a lens system that forms an image of the laser light reflected by the DMD on the scanning surface Each of these is controlled on and off to modulate laser light, and image exposure is performed on the photosensitive material 306 set on the stage 304 and moved along the scanning direction with the modulated laser light.

In addition, the exposure apparatus 300 follows the alignment function that corrects the exposure position deviation (X and Y directions) with respect to the photosensitive material 306, and the waviness and thickness (Z direction) variations of the photosensitive material 306. The photo-sensitive material 306 is equipped with an auto-focus function that focuses the laser beam on the surface to be exposed. The photo-sensitive material 306 is used as a reference for alignment for measuring the position (X, Y direction) of the photo-sensitive material 306. An alignment CCD camera 308 for detecting the alignment mark and the reference hole is disposed, and an automatic measuring device for measuring the distance (Z direction) from the exposed surface of the photosensitive material 306 on the upstream side of the exposure head 302. A focus displacement sensor 310 is provided.

[0005] In the exposure operation, the position of the photosensitive material 306 is measured by the CCD camera 308 before exposure ( The alignment reference part is detected), and the exposure misalignment correction control by the laser beam is performed based on the acquired measurement information. After the alignment measurement is completed, the displacement sensor 310 and the exposed surface of the photosensitive material 306 are detected. Perform distance measurement (focus measurement) and control the controller 390 based on the acquired measurement information to drive the focus mechanism provided on the laser beam emission side of the exposure head 302 or move the exposure head 302 in the optical axis direction. By adjusting and performing exposure while performing autofocus control so that the focus of the laser beam is aligned with the surface to be exposed, the accuracy of the exposure position and focus position by the laser beam is improved.

[0006] When a photosensitive material with large waviness and variation in thickness is used, the focus adjustment range in autofocus control, such as that used in the exposure apparatus 300 of the conventional digital scanning exposure method described above, is increased. If this is taken, high-precision exposure, which is difficult to maintain optical characteristics, becomes impossible, resulting in degradation of image quality.

For this reason, it is necessary to limit the focus adjustment range to a range where high-definition exposure is possible. On the other hand, when the focus adjustment range is limited in this way, when an exposure target with large waviness and thickness fluctuation is exposed, focus measurement is performed by the displacement sensor 310, and the distance between the photosensitive material 306 and the exposure head 302 is measured. When, for example, the fluctuation width D of the exposure object 30 6 exceeds the maximum focus range D of the exposure head 302, an error occurs due to the focus range being over, and as a result, the ratio at which exposure is impossible is detected. There is a problem if the yield increases and the yield decreases.

Patent Document 1: Japanese Patent No. 3305448

Disclosure of the invention

Problems to be solved by the invention

In view of the above facts, the present invention provides an exposure method and an exposure apparatus capable of preventing the occurrence of an error due to focus range over and ensuring the yield even when using a photosensitive material with large fluctuations in waviness and thickness. To do.

Means for solving the problem

[0009] An exposure method according to a first aspect of the present invention includes a plurality of exposure units that scan and expose a photosensitive material with a light beam modulated according to image information; A moving unit that relatively moves the photosensitive material in a direction along a scanning direction, a focus detection unit that detects a focal position of a light beam emitted from the plurality of exposure units, the plurality of exposure units, and the A distance measuring unit that measures a distance from the exposed surface of the photosensitive material, and a focal position of the light beam emitted from the plurality of exposure unit forces based on the distance information measured by the distance measuring unit on the exposed surface A focus control unit to be matched, and an exposure surface adjustment unit that moves the moving unit in a focus direction of the exposure unit, and the focus detection unit sets the center value of the focus position adjustment range in the focus control unit by the focus detection unit. The exposure surface adjustment unit calculates the plurality of exposure units, and the median of the maximum and minimum values of the distance information measured by the distance measurement unit approaches the median of the focus position adjustment range. Thus, after the moving unit is moved in the focus direction, an exposure operation is performed.

[0010] In the invention having the above-described configuration, it is possible to suppress a decrease in yield by moving the exposure stage so that the surface of the photosensitive material, that is, the exposed surface, approaches the center of the focus adjustment range, and reducing the error occurrence rate due to the range over. it can.

[0011] In the exposure method according to the second aspect of the present invention, when the maximum value and the minimum value of the distance information are within the focus position adjustment range, the exposure surface adjustment unit is not operated, and the distance information When the maximum value or the minimum value deviates from the focus position adjustment range, the median value of the distance information measured by the distance measuring unit approaches the median value of the focus position adjustment range. An exposure operation is performed again after the moving unit is moved in the focus direction by the exposure surface adjusting unit.

In the invention with the above configuration, when the maximum value or the minimum value of the distance information is out of the focus adjustment range force and an error occurs due to the range over, even the photosensitive material in which an error has occurred by moving the exposure stage and performing a retry is performed. Since exposure may be possible, waste of photosensitive material can be reduced and yield reduction can be suppressed.

The exposure method according to the third aspect of the present invention does not move the moving unit when the maximum value and the minimum value of the distance information are within a range including a predetermined margin from the focus position adjustment range. If the focus position adjustment range force is not within a range including a predetermined margin, the median value of the maximum and minimum values of the distance information measured by the distance measurement unit approaches the median value of the focus position adjustment range. How to focus the moving part by the exposure surface adjustment part In this case, the exposure operation is performed after moving in the direction.

In the invention with the above configuration, if the maximum value and the minimum value of the distance information are not within the range including the allowance for the focus adjustment range force, the exposure stage is moved, and the error occurrence rate due to the range over is increased. Lowering the yield can reduce the yield.

[0015] The exposure method according to the fourth aspect of the present invention is characterized in that the photosensitive material is not exposed when the difference between the maximum value and the minimum value of the distance information is out of the focal position adjustment range. And

In the invention with the above-described configuration, when the difference between the maximum value and the minimum value of the distance information is out of the focus adjustment range, it is possible to prevent the processing capacity from being lowered by not exposing the photosensitive material.

[0017] In the exposure method of the fifth aspect of the present invention, the plurality of light beams are relative to a photosensitive material placed on a moving part movable at least in the emission direction of the plurality of light beams. An exposure method in which exposure is performed while scanning, wherein a step of modulating the plurality of light beams according to image information, a step of adjusting a focal position of the plurality of light beams, and an exposure of the photosensitive material A step of measuring a surface position, a step of comparing a variation width of the exposed surface position along an emission direction of the plurality of light beams and a width capable of adjusting the focal position, and the variation And determining whether or not the photosensitive material can be exposed based on whether or not the width is smaller than the width at which the focus position can be adjusted.

In the invention having the above-described configuration, it is determined whether or not the photosensitive material can be exposed based on whether or not the fluctuation range of the exposed surface position is smaller than the adjustable range of the focal position. Therefore, it is possible to suppress a decrease in yield by lowering the error occurrence rate due to over-range.

[0019] In the exposure method of the sixth aspect of the present invention, the step of determining whether or not the position of the exposed surface is within a width that allows the adjustment of the focal position; And a step of moving the moving unit with respect to the emission direction when the variation range is smaller than a width within which the focal position can be adjusted and the fluctuation range is smaller than the width through which the focal position can be adjusted. To do. [0020] In the invention with the above configuration, it is possible to suppress a decrease in yield by reducing the error occurrence rate due to the range over by moving the moving unit with respect to the beam emission direction.

[0021] An exposure apparatus according to a seventh aspect of the present invention includes a plurality of exposure units that scan and expose a photosensitive material with a light beam modulated according to image information, and the exposure unit and the exposure unit that are mounted with the photosensitive material. A moving unit that relatively moves the photosensitive material in a direction along a scanning direction, a focus detection unit that detects a focal position of a light beam emitted from the plurality of exposure units, the plurality of exposure units, and the A distance measuring unit that measures a distance from the exposed surface of the photosensitive material, and a focal position of the light beam emitted from the plurality of exposure unit forces based on the distance information measured by the distance measuring unit on the exposed surface A focus control unit for matching, and an exposure surface adjustment unit for moving the moving unit in a focus direction of the exposure unit, and the focus detection unit sets the central value of the focus position adjustment range in the focus control unit to the focus control unit. Multiple exposures The exposure surface adjustment unit focuses the moving unit so that the median of the maximum and minimum values of the distance information measured by the distance measurement unit approaches the median of the focus position adjustment range. An exposure operation is performed after moving in the direction.

[0022] In the invention with the above configuration, the variation in thickness is great! Even when a photosensitive material is used, an error due to over focus range can be prevented, and a yield can be secured.

In the exposure apparatus according to the eighth aspect of the present invention, when the maximum value and the minimum value of the distance information are within the focus position adjustment range, the exposure surface adjustment unit is not operated, and the distance information When the maximum value or the minimum value deviates from the focus position adjustment range, the median value of the distance information measured by the distance measuring unit approaches the median value of the focus position adjustment range. An exposure operation is performed again after the moving unit is moved in the focus direction by the exposure surface adjusting unit.

The exposure apparatus according to the ninth aspect of the present invention does not move the moving unit when the maximum value and the minimum value of the distance information are within a range including a predetermined margin from the focus position adjustment range. If the focus position adjustment range force is not within a range including a predetermined margin, the median value of the maximum and minimum values of the distance information measured by the distance measurement unit approaches the median value of the focus position adjustment range. As described above, after the moving unit is moved in the focus direction by the exposure surface adjustment unit, an exposure operation is performed. [0025] The exposure apparatus according to the tenth aspect of the present invention is characterized in that the photosensitive material is not exposed when the difference between the maximum value and the minimum value of the distance information is out of the focal position adjustment range. And

The invention's effect

[0026] Since the present invention has the above-described configuration, an exposure method and an exposure apparatus capable of preventing an error due to overfocus range and ensuring a yield even when using a photosensitive material with large fluctuations in waviness and thickness. Can be provided.

Brief Description of Drawings

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

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

FIG. 3A is a view showing an arrangement of exposure areas by the exposure head according to the first embodiment of the present invention.

FIG. 3B is a view showing an arrangement of exposure areas by the exposure head according to the first embodiment of the present invention.

FIG. 4 is a perspective view showing the arrangement of an exposure head according to the first embodiment of the present invention.

FIG. 5A is a perspective view showing the arrangement of an exposure head according to the first embodiment of the present invention.

FIG. 5B is a perspective view showing the configuration of the exposure head according to the first embodiment of the present invention.

FIG. 6A is a diagram showing an exposure operation by the exposure apparatus according to the first embodiment of the present invention.

FIG. 6B is a diagram showing an exposure operation by the exposure apparatus according to the first embodiment of the present invention.

FIG. 7 is a view showing an exposure operation by the exposure apparatus according to the first embodiment of the present invention.

FIG. 8 is a view showing a photosensitive material positioning operation of the exposure apparatus according to the first embodiment of the present invention.

FIG. 9 is a view showing a photosensitive material positioning operation of the exposure apparatus according to the first embodiment of the present invention.

FIG. 10 is a diagram showing an exposure operation by a conventional exposure apparatus.

BEST MODE FOR CARRYING OUT THE INVENTION

FIG. 1 shows an exposure apparatus according to the first embodiment of the present invention.

As shown in FIG. 1, the exposure apparatus 100 includes a rectangular thick plate-like mounting table 156 supported by four legs 154. Two guides 158 are extended along the longitudinal direction on the upper surface of the installation table 156, and a rectangular flat plate-like stage 152 is provided on the two guides 158. The stage 152 is arranged such that the longitudinal direction thereof faces the extending direction of the guide 158, and is supported by the guide 158 so as to be able to reciprocate on the installation table 156. It is driven by the device and reciprocates along the guide 158. The photosensitive material 150 is attracted and held on the upper surface of the stage 152 in a state where the mounting position is determined by a positioning unit (not shown).

[0030] Gates 160 and 161 are arranged at predetermined intervals on the upstream side and the downstream side in the moving direction of the stage 152 with respect to the center of the installation table 156. The gates 160 and 161 are formed in a U shape so as to straddle the movement path of the stage 152, and both ends are fixed to both side surfaces of the installation table 156.

[0031] The gate 160 arranged on the upstream side in the moving direction of the stage 152 has three detection units 180 force S at the upper part of the front face (above the moving path of the stage 152) toward the upstream side. They are fixedly arranged at predetermined intervals along a direction orthogonal to the moving direction of the stage 152. In the detection unit 180, the CCD camera 182 arranged on the upstream side and the displacement sensor 184 arranged on the downstream side are integrated into a substantially box shape, and the lens unit 186 and the displacement sensor 184 of the CCD camera 182 are integrated. Both sensor parts 188 are directed downward.

[0032] In the gate 161 arranged on the downstream side in the moving direction of the stage 152, a scanner 162 is fixedly arranged on the upper part of the rear surface facing the downstream side (above the moving path of the stage 152). . The distance between the scanner 162 and the detection unit 180 is determined based on the exposure start position by an exposure head 166 provided later in the scanner 162 and the photographing position by the CCD camera 182 of the detection unit 180 (the optical axis center of the lens unit 186). The distance force of the photosensitive material 150 is set to be slightly longer than the longitudinal dimension.

In addition, the driving device of the stage 152, the scanner 162, and the detection unit 180 are connected to a controller 190 that controls them. The controller 190 controls the stage 152 to move at a predetermined speed during the exposure operation of the exposure apparatus 100 described later, the detection unit 180 is controlled to detect the photosensitive material 150 at a predetermined timing, and the exposure head 166 The photosensitive material 150 is controlled to be exposed at a predetermined timing.

FIG. 2 and FIGS. 3A and B show an exposure head according to the first embodiment of the present invention.

As shown in FIGS. 2 and 3B, the scanner 162 includes a plurality of (for example, eight) exposure heads 166 arranged in a substantially matrix of m rows and n columns (eg, 2 rows and 4 columns). I have. As shown in FIG. 2, an exposure area 168 that is an area exposed by the exposure head 166 has a rectangular shape with a short side along the scanning direction, and is inclined at a predetermined inclination angle Θ with respect to the scanning direction. is doing. As the stage 152 moves, a strip-shaped exposed area 170 is formed on the photosensitive material 150 for each exposure head 166. As shown in FIGS. 1 and 2, the scanning direction is opposite to the stage moving direction.

[0037] As shown in FIGS. 3A and 3B, the exposure heads 166 are arranged in a line, and the strip-shaped exposed areas 170 partially overlap the adjacent exposed areas 170. The arrangement direction is shifted by a predetermined interval (a natural number multiple of the long side of the exposure area, which is 1 in this embodiment). For this reason, for example, an unexposed portion between the image area 168A located on the leftmost side of the first line and the image area 168C located right next to the image area 168A is located on the leftmost side of the second line. It is exposed by the located image area 168B. Similarly, the non-exposure portion between the image area 168B and the image area 168D located on the right side of the image area 168B is exposed by the image area 168C.

4, FIG. 5A and B show an optical system of the exposure head according to the first embodiment of the present invention.

Each of the exposure heads 166A to 166H, as shown in FIG. 4, FIG. 5A and B, is a digital light source as a spatial light modulation element that modulates an incident light beam for each pixel according to image data. It is equipped with a micromirror device (DMD) 50. The DMD 50 is connected to the controller 190 having a scanner control unit including a data processing unit and a mirror drive control unit. The data processing unit of the controller 190 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.

In addition, the mirror drive control unit controls the angle of the reflection surface of each micromirror of the DMD 50 for each exposure head 166 based on the control signal generated by the data processing unit. The control of the angle of the reflecting surface will be described later.

[0041] On the light incident side of the DMD 50, a fiber array light source including a laser emitting portion in which the emitting end portion (light emitting point) of the optical fiber is arranged in a line along the direction corresponding to the long side direction of the exposure area 168 66, Correcting the laser beam emitted from the fiber array light source 66 on the DMD50 A lens system 67 for condensing light and a reflecting mirror 69 for reflecting the laser light transmitted through the lens system 67 toward the DMD 50 are arranged in this order.

[0042] The lens system 67 is a pair of combination lenses 71 that collimate the laser light emitted from the fiber array light source 66, and corrects the light quantity distribution of the collimated laser light to be uniform 1 A pair of combination lenses 73 and a condensing lens 75 that condenses the laser light whose light intensity distribution is corrected on the DMD 50 are configured. The combination lens 73 is close to the optical axis of the lens with respect to the arrangement direction of the laser emitting ends, the part spreads the light flux, the part away from the optical axis shrinks the light flux, and is orthogonal to the arrangement direction. On the other hand, it has a function of allowing light to pass through as it is, and corrects the laser light so that the light quantity distribution is uniform.

Further, on the light reflection side of the DMD 50, as shown in FIG. 5, lens systems 54 and 58 for forming an image of the laser light reflected by the DMD 50 on the scanning surface (exposed surface) 56 of the photosensitive material 150, lenses A focus mechanism 59 for adjusting the focal length of the laser light transmitted through the systems 54 and 58 is arranged in this order.

The lens systems 54 and 58 are arranged so that the DMD 50 and the exposed surface 56 are in a conjugate relationship. In this embodiment, the laser light emitted from the fiber array light source 66 is made uniform, After entering the DMD 50, each pixel is enlarged by about 5 times by these lens systems 54 and 58, and is set to be condensed.

Next, the exposure operation for the photosensitive material 150 by the exposure apparatus 100 configured as described above will be described with reference to FIGS. 6A, 6 B, and 7.

First, when image data corresponding to an exposure pattern is input to the controller 190, it is stored in a frame memory in the controller. This image data is data in which the density of each pixel constituting the image is represented by binary values (whether or not dots are recorded).

Next, the photosensitive material 150 is set on the stage 152, and the operator performs an input operation for starting exposure from the operation unit of the controller 190. The photosensitive material 150 for performing image exposure with the exposure apparatus 100 is a photosensitive epoxy on the surface of a substrate or glass plate as a material for forming a pattern (image exposure) such as a printed wiring board or a liquid crystal display device. For example, coated with a photoresist such as grease or laminated film in the case of dry film.

When the exposure operation of the exposure apparatus 100 is started by the above input operation, the controller 190 1 controls the driving device, and the stage 152 starts to move at a constant speed along the guide 158 on the origin position force shown in FIG. Each detection unit 180 is controlled and operated by the controller 190 in synchronization with the start of the movement of the stage or at a timing just before the leading edge of the photosensitive material 150 reaches just below the CCD camera 182 of the detection unit 180.

As the stage 152 moves, when the photosensitive material 150 passes below the detection unit 180, the alignment measurement by the CCD camera 182 and the focus measurement by the displacement sensor 184 are simultaneously performed.

[0050] First, as shown in FIGS. 6A, 6B and 7, when the photosensitive material 150 passes under the three CCD cameras 182, each CCD camera 182 takes an image of the photosensitive material 150, and the image is taken. The obtained image data (photographing data) is output to the data processor of the controller 190.

[0051] The data processing unit detects an alignment mark or a reference hole provided in the photosensitive material 150 as a reference portion for alignment, or an edge portion or a corner portion of the photosensitive material 150, etc., from the input photographing data. Thus, grasp the position of the photosensitive material 150 and the appropriate exposure position with respect to the exposed surface 56. At the time of image exposure by the scanner 162, correction control (alignment) is performed in which a control signal generated based on the image data of the exposure pattern stored in the frame memory is adjusted to the appropriate exposure position to perform image exposure.

[0052] When the photosensitive material 150 passes below the displacement sensor 184, each displacement sensor 184 is connected to the exposed surface 56 including detection (edge detection processing) of the front and rear ends of the photosensitive material 150. The distance is measured (FIG. 7A), and the measured distance data (focus measurement data) is output to the scanner control unit of the controller 190.

The scanner control unit of the controller 190 recognizes the leading end and the trailing end of the photosensitive material 150 based on the input focus measurement data, and calculates the waviness and thickness dimension error of the photosensitive material 150. Execute. Further, based on this processing result, a control signal for driving and controlling the focus mechanism 59 of each exposure head 166 is generated and output to the scanner 162, and the focal position of the light beam emitted from each exposure head 166 is determined as a photosensitive material. Focus control is performed to match the exposed surface 56 of 150. In this scanning exposure, the focus of the laser light is adjusted on the exposed surface 56 so as to follow the shape of the exposed surface 56 and follow the shape of the exposed surface 56 in synchronism with the scanning by focus control. [0054] At this time, the scanner control unit of the normal controller 190 sets the difference between the maximum value and the minimum value of the mapping data iso-force Z coordinate value (optical axis direction) created based on the focus measurement data V in advance. If the difference between the maximum value and the minimum value exceeds the threshold value, the waviness or thickness dimension error of the photosensitive material 150 is large and the accuracy is poor. Then, the controller 190 performs error control. In the error control, when it is determined that the photosensitive material 150 is inaccurate, the image exposure by the scanner 162 is not shifted to, but the exposure operation is immediately stopped and the stage 152 is returned to the most upstream position. Then, information (error information) for notifying that the exposure operation is stopped is displayed on the monitor of the controller 190. That is, the photosensitive material 150 is not exposed.

[0055] This is because the focus of the photosensitive material 150 can be adjusted so that the focus of the laser beam can be adjusted on the exposed surface 56 so as to follow the shape of the exposed surface 56 in a synchronized manner with the scanning. Or, this is because the fluctuation range of the exposed surface 56 caused by the thickness dimension error needs to be within the focus adjustment range of the laser beam.

[0056] Even if the waviness or thickness error of the photosensitive material 150 is large as described above, the difference between the maximum value and the minimum value of the Z coordinate value (in the optical axis direction). If it is within the maximum width of the point adjustment range, exposure is actually possible and there is no need to treat it as an error.

That is, even when the waviness or thickness dimension error of the photosensitive material 150 is large as described above, depending on the position in the focus direction of the stage 152 on which the photosensitive material 150 is placed, the variation range of the exposed surface 56 may be the focal point of the laser beam. Since it is within the adjustment range, errors can be prevented and yield can be prevented from decreasing.

FIG. 8 shows the relationship between the exposure apparatus and the exposed surface according to the first embodiment of the present invention.

[0059] The focus adjustment range of the exposure head 166, that is, the shortest focus position N166 and the farthest force position F166 is C166, and the focus adjustment range is D166. On the surface of the photosensitive material 150 placed on the stage 152, If the fluctuation range of an exposed surface 56 is within D166, as described above, the focus of the laser beam follows the shape of the exposed surface 56, and the exposure head 166 is driven to focus on the exposed surface 56 so that it smoothly follows. The exposure can be performed. [0060] Here, the stage 152 is moved in the Z direction, that is, in the direction of the optical axis so that the surface C56 of the photosensitive material 150 on the stage 152, that is, the center C56 of the fluctuation range of the exposed surface 56 approaches C166 which is the center of the D166. Move.

Specifically, as shown in FIG. 8, the moving device 157 provided on the installation table 156 is driven, and the stage 152 is moved in the Z direction, that is, in the optical axis direction. The center C56 of (the difference between the closest point N56 to the exposure head 166 and the farthest point F56 = D56) is brought close to the median value C166 of the focus adjustment range of the exposure head 166.

[0062] As a result, the center C56 of D56, which is the fluctuation range of the exposed surface 56 due to the waviness or thickness dimension error of the photosensitive material 150, approaches C166, and each exposure head 166 performs focus adjustment by the auto force mechanism. Will be. C166 is the center position of the focus adjustment range of each exposure head 166. By bringing the surface of the photosensitive material 150, that is, the variation range D56 of the exposed surface 56, C56 closer to this C166, the swell or thickness of the photosensitive material 150 is obtained. Fluctuation range of exposed surface 56 due to dimensional error It becomes easy to fit D56 into D166, which is the focus adjustment range of each exposure head 166. As a result, the above error (range over error) is prevented and yield is also prevented. be able to.

[0063] Further, as described above, one of the point N56 closest to the exposure head 166 and the point F56 farthest from the exposed surface 56 due to the waviness or thickness dimension error of the photosensitive material 150 is out of the focus adjustment range D166. As a result, a range over error may occur and exposure may not be possible.

[0064] At this time, the above-described operation, that is, the operation of bringing the center C56 of D56, which is the fluctuation range of the exposed surface 56, close to the center value C166 of the focus adjustment range of the exposure head 166, is performed, and a retry is performed. Therefore, even a photosensitive material 150 that is determined to be unusable may be exposed.

In other words, even if D56 itself, which is the fluctuation range of the exposure surface 56, is within the focus adjustment range D166 of the exposure head 166, a range error will occur if either N56 or F56 is out of D166. If the above operation allows both N56 and F56 to fit in D166, the range over error will be eliminated, and even light sensitive material 150 determined to be unusable can be exposed. This increases the usable photosensitive material 150. As a result, the processing speed can be reduced by the time required for retrying, and the yield can be improved and the cost can be reduced.

[0066] Further, here, the lifting device 157 is a force that is provided on the installation base 156 and serves as a mechanism for adjusting the height of the guide 158. However, the present invention is not limited to this. For example, the lifting device 157 may be provided between the guide 158 and the stage 152. Good.

[0067] In the conventional exposure apparatus, the measurement data force of the distance from the exposed surface 56 of the photosensitive material 150 measured by the displacement sensor 184. The concave and convex shape of the exposed surface 56 due to the waviness and warpage of the photosensitive material 150, etc. If the preset threshold value is exceeded due to a large error or a large thickness dimensional error of the photosensitive material 150, the scanner control unit of the controller 190 does not perform exposure to the photosensitive material 150. I was controlling 162.

[0068] Therefore, the photosensitive material 150 that is determined to be incapable of being exposed cannot be used, resulting in a loss of photosensitive material and a decrease in yield, resulting in an increase in cost.

[0069] However, in the present invention, by preventing the occurrence of an error itself, it is possible to prevent a decrease in yield and suppress an increase in cost.

FIG. 9 shows the relationship between the exposure apparatus and the exposed surface according to the second embodiment of the present invention.

[0071] The focus adjustment range of the exposure head 166, that is, the shortest focus position N166 and the farthest force position F166 is the median of C166, the focus adjustment range is D166, and is closest to the exposure head 166 in the fluctuation range of the exposure surface 56 Point N56, point F56 farthest from exposure head 166, fluctuation range of exposed surface 56 (N56-F56) is D56, middle of D56, C56, difference between shortest focus position N16 6 and N56 is H1, maximum If the difference between the far focus positions F166 and F56 is H2, if HI and H2 are larger than the preset tolerance Δ

Η1≥ Δ かつ and Η2≥ Δ Η

If it is, it can expose as it is. In this case, by determining whether exposure is possible or not by a value that has a margin of ΔΗ from the shortest focus position N166 and the farthest focus position F166, the fluctuation range D56 of the exposed surface 56 is Δ Δ more than the focus adjustment range D166. Because it fits in / out with only a margin, the optical performance does not become the limit of the focus position, and exposure can be carried out with a margin even if you go to Ν56 or F56. Also, exposure of photosensitive material 150 for some reason Even if the optical surface 56 is shifted in the focus direction, focusing is possible within the range of ΔH, so that the risk of wasting the photosensitive material 150 can be reduced.

[0072] When the fluctuation range D56 of the exposed surface 56 is larger than the focus adjustment range D166, naturally, N

Since at least one of 56 and F56 is out of the focus adjustment range, focusing cannot be performed, and a part of the light-sensitive material 150 cannot be imaged.

Therefore, in the above case, if exposure is impossible when it is determined that the fluctuation range D56 of the surface to be exposed 56 is larger than the focus adjustment range D166, it is possible to prevent a reduction in processing capability.

Industrial applicability

[0074] It is possible to provide an exposure method and an exposure apparatus capable of preventing the occurrence of errors due to overfocus range and ensuring the yield even when using a photosensitive material with large fluctuations in waviness and thickness.

Explanation of symbols

[0075] 56 Surface to be exposed

59 Focus mechanism (Focus 咅

100 exposure equipment

150 photosensitive material

152 stage (moving part)

157 Lifting device

162 Scanner (exposure section)

166 Exposure head (Exposure part Z exposure head)

180 detection unit

182 CCD camera (reference part detection part)

184 Displacement sensor (distance measuring unit)

190 Controller (Control unit)

Claims

The scope of the claims

[1] a plurality of exposure units that scan and expose a photosensitive material with a light beam modulated according to image information;

A moving unit for placing the photosensitive material and relatively moving the exposure unit and the photosensitive material in a direction along a scanning direction;

A plurality of exposure unit forces; a focus detection unit that detects a focal position of the emitted light beam; a distance measurement unit that measures a distance between the plurality of exposure units and an exposed surface of the photosensitive material; and the distance measurement unit. A focus control unit that matches the focal position of the light beam on which the plurality of exposure unit forces are also projected based on the distance information measured by the step, and the moving unit is moved in the focus direction of the exposure unit An exposure surface adjustment unit, and the focus detection unit calculates a center value of the focus position adjustment range in the focus control unit for the plurality of exposure units,

The exposure unit is moved in the focus direction by the exposure surface adjustment unit so that the median of the maximum and minimum values of the distance information measured by the distance measurement unit approaches the median of the focus position adjustment range. An exposure method comprising performing an exposure operation later.

[2] When the maximum value and the minimum value of the distance information are within the focus position adjustment range, the exposure surface adjustment unit is not operated,

When either the maximum value or the minimum value of the distance information is out of the focus position adjustment range, the median value of the maximum value and the minimum value of the distance information measured by the distance measurement unit is the focus position. 2. The exposure method according to claim 1, wherein the exposure operation is performed again after moving the moving unit in the focus direction by the exposure surface adjusting unit so as to approach the median value of the adjustment range.

[3] When the maximum value and the minimum value of the distance information are within a range including a predetermined margin from the focus position adjustment range, the moving unit is not moved,

When it is not within the range including the predetermined margin from the focal position adjustment range, the median of the maximum and minimum values of the distance information measured by the distance measurement unit becomes the median of the focal position adjustment range. 2. The exposure method according to claim 1, wherein an exposure operation is performed after the moving unit is moved in the focus direction by the exposure surface adjustment unit so as to approach.

[4] The exposure material according to any one of claims 1 to 3, wherein the photosensitive material is not exposed when a difference between a maximum value and a minimum value of the distance information is out of the focus position adjustment range. The exposure method as described.

[5] An exposure method in which exposure is performed while relatively scanning the plurality of light beams with respect to a photosensitive material placed on a moving portion that is movable in at least the emission direction of the plurality of light beams. And

Modulating the plurality of light beams according to image information;

Adjusting the focal position of the plurality of light beams;

Measuring the exposed surface position of the photosensitive material;

Comparing a variation width of the exposed surface position along an emission direction of the plurality of light beams with a width capable of adjusting the focus position;

Determining whether or not the photosensitive material can be exposed based on whether or not the fluctuation width is smaller than a width allowing adjustment of the focal position;

An exposure method comprising:

[6] A step of determining whether or not the position of the exposed surface is within a range in which the focus position can be adjusted;

When the exposed surface position falls within a range in which the focus position can be adjusted and the variation width is smaller than a width in which the focus position can be adjusted, the moving unit is moved with respect to the exit direction. 6. The exposure method according to claim 5, further comprising a moving step.

[7] A plurality of exposure units that scan and expose the photosensitive material with a light beam modulated according to image information;

A plurality of exposure unit forces; a focus detection unit that detects a focal position of the emitted light beam; a distance measurement unit that measures a distance between the plurality of exposure units and an exposed surface of the photosensitive material; and the distance measurement unit. A focus control unit that matches the focal position of the light beam on which the plurality of exposure unit forces are also projected based on the distance information measured by the step, and the moving unit is moved in the focus direction of the exposure unit An exposure surface adjustment unit, The focus detection unit calculates a central value of the focus position adjustment range in the focus control unit for the plurality of exposure units,

The exposure unit is moved in the focus direction by the exposure surface adjustment unit so that the median of the maximum and minimum values of the distance information measured by the distance measurement unit approaches the median of the focus position adjustment range. Then, an exposure apparatus that performs an exposure operation.

[8] When the maximum value and the minimum value of the distance information are within the focus position adjustment range, the exposure surface adjustment unit is not operated.

When either the maximum value or the minimum value of the distance information is out of the focus position adjustment range, the median value of the maximum value and the minimum value of the distance information measured by the distance measurement unit is the focus position. 8. The exposure apparatus according to claim 7, wherein the exposure operation is performed again after moving the moving unit in the focus direction by the exposure surface adjusting unit so as to approach the median value of the adjustment range.

[9] When the maximum value and the minimum value of the distance information are within a range including a predetermined margin from the focus position adjustment range, the moving unit is not moved,

When it is not within the range including the predetermined margin from the focal position adjustment range, the median of the maximum and minimum values of the distance information measured by the distance measurement unit becomes the median of the focal position adjustment range. 8. The exposure apparatus according to claim 7, wherein an exposure operation is performed after moving the moving unit in a focusing direction by the exposure surface adjustment unit so as to approach the exposure unit.

[10] The exposure material according to any one of claims 7 to 9, wherein the photosensitive material is not exposed when a difference between a maximum value and a minimum value of the distance information is out of the focus position adjustment range. The exposure apparatus described.