KR20200000343A - Mark position detecting apparatus, writing apparatus and mark position detecting method - Google Patents

Abstract

The present invention relates to a drawing apparatus comprising a function as a mark position detection apparatus which detects the position of a mark on a substrate maintained at a stage. The drawing apparatus comprises: a first image (83a) representing a first area on the substrate including a design position of the mark while moving the stage; and two second images (83b) representing a second area in which only a part of the first area overlaps. In addition, a synthesized image (85) is generated by synthesizing the first image (83a) and the second image (83b). The drawing apparatus obtains the position of the mark based on the synthesized image (85). Therefore, the field of view can be easily enlarged without lowering the resolution of an imaging unit, and a detection error of the mark position on the substrate can be reduced.

Description

MARK POSITION DETECTING APPARATUS, WRITING APPARATUS AND MARK POSITION DETECTING METHOD}

This invention is used with respect to the technique which detects the position of the mark on a board | substrate, Preferably it is used for the drawing apparatus which draws a pattern on a board | substrate.

Background Art Conventionally, a drawing apparatus that irradiates light onto a substrate and draws a pattern directly on the substrate has been used in various scenes. Such a drawing method is also called direct imaging. Before drawing, the position of the mark called alignment mark formed on the board | substrate is read by the imaging part, and the deviation amount of the mark position from a design position is calculated | required. Further, the position, the amount of stretching, the amount of deformation, and the like of the substrate are determined based on the amount of misalignment, and drawing is performed while correcting the drawing data in real time with reference to these information. Thereby, drawing is performed with high precision according to the position shift and deformation | transformation of a board | substrate. As such drawing apparatus, the apparatus disclosed by Unexamined-Japanese-Patent No. 2015-64461 is mentioned, for example. Direct imaging is suitable for drawing on the board | substrate which has the flexibility with large positional shift and deformation | transformation of a board | substrate.

By the way, depending on the kind and quality of a board | substrate, the position of a mark may shift largely on the stage which supports a board | substrate. For example, in the case of the board | substrate which has flexibility, since the cutting precision at the time of board | substrate manufacture is low, and handling precision is also low, the position shift of the mark at the time of mounting a board | substrate to a stage becomes large. In the case of a flexible substrate, the deformation of the substrate, such as expansion and contraction, or distortion, is also a cause of the positional shift of the mark. As a result, when imaging a mark, the frequency with which a mark is located out of an imaging range becomes high. If detection of a mark position fails once, a manufacturing line stops and productivity falls largely.

In order to be able to image even if the position of the mark is greatly shifted from the desired position, for example, it is necessary to move the imaging unit away from the table or lower the magnification of the optical system to widen the imaging range. In this case, the resolution of the image is lowered and the detection accuracy of the mark position is lowered. In order to maintain the resolution, it is necessary to increase the number of pixels of the imaging sensor. In this case, the imaging section becomes expensive and the imaging section becomes physically large.

An object of the present invention is to reduce the detection error of the mark position by easily expanding the field of view without lowering the resolution of the imaging unit.

The present invention relates to a mark position detection device for detecting the position of a mark on a substrate held on a stage. A mark position detection device according to a preferred embodiment of the present invention includes a stage holding a substrate, an image pickup portion for acquiring an image of a mark formed on the substrate, and a direction parallel to the main surface of the substrate, with respect to the image pickup portion. A movement mechanism for relatively moving the stage, a first image representing a first region on the substrate including a design position of the mark by controlling the imaging unit and the movement mechanism, and only a portion of the first region An imaging control unit for acquiring a second image representing the overlapping second region, an image synthesizing unit for synthesizing the first image and the second image to generate a synthesized image, and the image for the stage based on the synthesized image. And a position acquiring unit for obtaining the position of the mark.

According to the present invention, the field of view can be easily enlarged without lowering the resolution of the imaging unit, and the detection error of the mark position on the substrate can be reduced.

Preferably, each of the first region and the second region has a long side and a short side perpendicular to each other, and the first region and the second region are arranged in a direction substantially parallel to the short side.

More preferably, the image synthesizing unit, when obtaining the relative position of the second image with respect to the first image, the short sides of the first region and the second region, the center of the first region and the second region; The angle formed by the straight line connecting the center of the area is used.

Preferably, the moving mechanism moves the stage relative to the imaging unit in a moving direction and in a straight line, and the imaging unit performs the first image and the operation during relative movement of the stage with respect to the imaging unit. Acquire a second image.

Preferably, the moving mechanism moves the stage relative to the imaging unit relative to the moving direction and in a straight line, and the imaging unit acquires images of an odd number of regions arranged in the moving direction, Each of the plurality of regions overlaps with an adjacent region only partially, the first region is a region in the center of the plurality of regions, and the second region is one region adjacent to the first region.

Preferably, the pixel value of the part where the said 1st image and other images overlap in the said composite image is a pixel value of the said 1st image.

In a preferable embodiment, the mark position detection device further includes another imaging unit for acquiring an image of another mark formed on the substrate, and the imaging control unit controls the other imaging unit and the moving mechanism, thereby providing the other mark. Obtains another first image representing another first region on the substrate including a design position of; and another second image representing another second region only partially overlapping with the other first region; The other first image and the other second image are synthesized to generate another synthesized image, and the size of the synthesized image and the size of the other synthesized image are the same.

Preferably the substrate is flexible.

The present invention also relates to a drawing apparatus for drawing a pattern on a substrate. The drawing device includes the above-described mark position detection device for detecting a plurality of mark positions formed on a substrate, a correction unit for correcting drawing data based on the plurality of mark positions, and light modulated by the substrate on the stage. And a drawing control unit which executes a drawing on the substrate based on the corrected drawing data by controlling the drawing head for irradiating the drawing and the moving mechanism and the drawing head.

The present invention also relates to a mark position detection method for detecting the position of a mark on a substrate held on a stage. The mark position detection method includes a) a process of acquiring a first image representing a first region including a design position of a mark on a substrate held on a stage, and b) a second region in which only a portion of the first region overlaps. Acquiring a second image to be shown; c) synthesizing the first image and the second image to generate a synthesized image; and d) obtaining a position of the mark relative to the stage based on the synthesized image. Process.

The above-mentioned object and other objectives, a characteristic, aspect, and an advantage are revealed by the detailed description of this invention performed below with reference to an accompanying drawing.

1 is a block diagram showing the configuration of a drawing system.
2 is a perspective view of the apparatus main body.
3 is a side view showing a part of the apparatus main body;
4 is a block diagram showing the functional configuration of the computer together with the peripheral configuration.
5 is a diagram illustrating a flow of an operation of the drawing apparatus.
6 is a plan view showing an example of mark arrangement on a substrate.
7 is a diagram illustrating an area on a substrate to be imaged.
8 is a diagram for explaining processing of an image combining unit.
9 is a diagram for explaining processing of the image combining unit.

1 is a block diagram showing the configuration of a drawing system 100 according to an embodiment of the present invention. The drawing system 100 is a system which irradiates light to photosensitive materials on board | substrates, such as a printed wiring board, and draws patterns, such as wiring, on the said photosensitive material. Preferably, the substrate is a printed wiring board having flexibility. As a board | substrate, various other things can be used and the board | substrate used other than the wiring of a rigid board | substrate and a circuit may be sufficient.

The writing system 100 includes a computer 101 and a drawing device 1. The drawing apparatus 1 includes the function as a mark position detection apparatus which detects the position of the mark on a board | substrate. The computer 101 is used for generation of design data indicating the entire pattern to be drawn on the substrate. The design data is vector data representing the entire pattern, for example. The drawing device 1 includes a computer 21 and an apparatus main body 10. The computer 21 is responsible for the overall control of the apparatus main body 10. The computer 21 also executes generation of drawing data used in the apparatus main body 10 from the design data. The computer 101, the computer 21, and the apparatus main body 10 are connected to be able to communicate with each other.

2 is a perspective view of the apparatus main body 10. In FIG. 2, three directions orthogonal to each other are indicated by arrows in the X direction, the Y direction, and the Z direction (the same as in other drawings). In the example of FIG. 2, the X direction and the Y direction are horizontal directions, and the Z direction is vertical direction. Depending on the design of the drawing device 1, the Z direction may be a direction inclined with respect to the vertical direction or a horizontal direction.

The apparatus main body 10 includes a plurality of drawing heads 31, a stage 41, a stage elevating mechanism 42, a stage moving mechanism 43, and an imaging unit 5. The stage 41 holds the substrate 9 below the drawing head 31 ((-Z) side). The plurality of drawing heads 31 are arranged in the X direction (hereinafter referred to as "width direction"). In each drawing head 31, a laser beam is emitted from a light source toward a light modulation unit, and the light is modulated by the light modulation unit. The modulated (spatial modulated) light is irradiated onto the main surface 91 in the (+ Z) direction in the substrate 9 on the stage 41. In this embodiment, a DMD (digital mirror device) in which a plurality of micromirrors are arranged two-dimensionally is used as the light modulating portion of each drawing head 31. The light modulating unit may be a modulator in which a plurality of light modulating elements are arranged in one dimension.

The stage elevating mechanism 42 moves the stage 41 in the Z direction. The stage moving mechanism 43 moves the stage 41 together with the stage elevating mechanism 42 in the Y direction (hereinafter, referred to as a "moving direction"). The stage moving mechanism 43 is a mechanism for moving the stage 41 linearly along the guide rail, for example, and a linear servo motor is used as a drive source, for example. As a result, the stage 41 moves with high precision. As a drive source of the stage movement mechanism 43, what attached the motor to the ball screw may be used. In the drawing apparatus 1, the stage elevating mechanism 42 may be omitted, and the rotating mechanism which rotates the stage 41 about the axis parallel to Z direction may be provided.

The imaging unit 5 is arrange | positioned at the (-Y) side of the some drawing head 31. FIG. The imaging unit 5 has a plurality of imaging units 51. The plurality of imaging sections 51 are arranged at intervals in the width direction. Each imaging unit 51 captures the substrate 9 on the stage 41 and acquires image data. The imaging part 51 acquires the image formed on the board | substrate 9, what is called an alignment mark. The imaging unit 51 is a so-called digital still camera that includes a two-dimensional image sensor and an imaging optical system.

On the stage 41, the contact part 411 which contacts the edge of the board | substrate 9 is formed. When the board | substrate 9 is mounted on the stage 41, the edge and the edge of the board | substrate 9 contact the contact part 411, and the position and direction on the stage 41 of the board | substrate 9 are determined. In this embodiment, the contact part 411 is three pins. The contact part 411 is not limited to a pin, For example, it may be a site | part which protrudes upward while extending | stretching to an X direction and a Y direction. The substrate 9 is fixed on the stage 41 by suction adsorption. The substrate 9 may be fixed to the stage 41 by another method.

In the drawing of the pattern by the drawing head 31, the stage moving mechanism 43 continuously moves the stage 41 in the movement direction, and the position on the substrate 9 to which the light from each drawing head 31 is irradiated. Then, the substrate 9 is scanned in the movement direction. In addition, in synchronization with the movement of the stage 41, the DMD of the drawing head 31 is controlled. Thereby, drawing of the pattern by each drawing head 31 is performed with respect to the strip | belt area | region extended on the main surface 91 in a movement direction.

In this embodiment, a pattern is drawn in the whole drawing area | region of the board | substrate 9 by one continuous movement of the stage 41 in a movement direction (so-called one-pass drawing). In the drawing apparatus 1, drawing of the pattern with respect to the whole drawing area may be performed by repeating the continuous movement of the stage 41 in a movement direction, and the intermittent movement in the width direction perpendicular | vertical to a movement direction multiple times. (So-called multi-pass drawing).

3 is a side view illustrating a part of the apparatus main body 10. 3 is a view of the apparatus main body 10 viewed in the (-X) direction. Each imaging unit 51 can move in the X direction by the imaging unit moving mechanism 52. The imaging unit moving mechanism 52 combines, for example, a mechanism for driving the ball screw with a motor and a mechanism for guiding in the X direction. A linear servo motor may be used as a drive source of the imaging unit moving mechanism 52. The imaging unit 51 has an illumination unit 53. The lighting unit 53 is a ring lighting device. As the illumination part 53, the apparatus which irradiates the illumination light to the board | substrate 9 through an imaging optical system may be employ | adopted. As the illumination part 53, the ring illuminating device and the apparatus which illuminates through the imaging optical system may be combined.

The scale 44 is attached to the edge part at the (+ Y) side of the stage 41. The scale 44 may be formed at another position as long as it is fixed to the stage 41. The scale 44 is long in the X direction and exists in the entire range which can be drawn in the X direction. The scale 44 is a transparent plate and has a plurality of cross patterns arranged in the X direction on the plate. Other shapes may be employed as the pattern that the scale 44 has.

Below the scale 44, the lower imaging part 61 is arrange | positioned. The lower image pickup section 61 can move in the X direction by the lower image pickup section moving mechanism 62. The lower imaging part movement mechanism 62 combines the mechanism which drives a ball screw with a motor, and the mechanism which guides to an X direction, for example. A linear servo motor may be used as a drive source of the lower imaging unit moving mechanism 62. In the state where light of a predetermined pattern is emitted toward the scale 44 from one drawing head 31, the lower imaging part 61 acquires the image of the scale 44, and arithmetic-processes the said image, and is drawing. The positional relationship between the head 31 and the scale 44 is obtained. Since the scale 44 is fixed to the stage 41, the positional relationship of the drawing head 31 and the stage 41 is also acquired.

Each drawing head 31 is movable in the X direction by the head moving mechanism 32. The head movement mechanism 32 combines the mechanism which drives a ball screw with a motor, for example, and the mechanism which guides to a X direction. A linear servo motor may be used as the drive source of the head moving mechanism 32. Acquisition of the positional relationship of each drawing head 31 and the stage 41 is performed whenever the drawing head 31 is rearranged according to the pattern to draw on the board | substrate 9. By moving the one lower image pickup section 61 in the X direction, the positional relationship between all the drawing heads 31 and the stage 41 may be acquired, and a plurality of lower image pickup sections 61 are formed to form one lower image pickup section. 61 may acquire the relationship of one part of the drawing head 31 and the stage 41.

Moreover, the positional relationship of the imaging part 51 and the stage 41 is also acquired by changing the position of the stage 41 and imaging the scale 44. The acquisition of the positional relationship between the image capturing unit 51 and the scale 44 may be performed only once before drawing, but may be performed every time the stage 41 moves during imaging of a mark to be described later.

4 is a block diagram showing the functional configuration of the computer 21 together with the peripheral configuration. The functional configuration of the computer 21 is realized by the computer 21 executing a program. That is, each functional configuration is realized by the CPU, ROM, RAM, fixed disk, interface, etc. of the computer 21 operating in accordance with the program. Each functional configuration may be realized by execution of a dedicated electrical circuit or a dedicated electrical circuit and a program. The computer 21 may be a plurality of computers or may be realized by a combination of a dedicated electric circuit and a plurality of computers.

The computer 21 includes an imaging control unit 211, an image synthesizing unit 212, a position obtaining unit 213, a correcting unit 214, a drawing control unit 215, and a storage unit 216. do. The storage unit 216 is mainly realized by a fixed disk device or a memory device of the computer 21. The imaging control unit 211 controls the stage moving mechanism 43, and controls the imaging by the imaging unit 51 in accordance with a signal from the stage moving mechanism 43. The image synthesizing unit 212 synthesizes a plurality of images acquired by the imaging unit 51. The position acquisition part 213 acquires the position of the mark with respect to the stage 41 based on the image (henceforth a "mark image") of the mark shown in a synthesized image. The storage unit 216 stores the drawing data 8. The correction unit 214 acquires the position or deformation of the substrate 9 based on the position of the mark, and corrects the drawing data 8. The drawing control unit 215 controls the stage moving mechanism 43 and the drawing head 31 and executes drawing on the substrate 9 based on the corrected drawing data 8.

Acquisition of an image in the following description is exactly acquisition of image data, and processing for an image is exactly processing for data of an image.

5 is a diagram illustrating an operation flow of the drawing device 1. As described above, in the drawing apparatus 1, after detection of the mark position on the board | substrate 9 is performed (steps S11-S15), drawing data according to the position or deformation of the board | substrate 9 based on the position of a mark. (8) is corrected (step S16), and a pattern is drawn on the board | substrate 9 according to the drawing data on which correction was completed (step S17). The "mark position" is exactly the position of the mark with respect to the reference position set based on the stage 41. "Position with respect to the stage 41" means a relative position with respect to the reference position set in the stage 41.

6 is a plan view illustrating an example of the arrangement of the marks 92 on the substrate 9. The mark 92 is, for example, a minute hole formed in the substrate 9 or a pattern of copper foil formed on the substrate 9. As a pattern of copper foil, various patterns, such as a cross and a circle, can be used. In the case of the example of FIG. 9, nine marks 92 are arranged in three rows and three columns in the X direction and the Y direction. The position of the mark 92 in the X direction corresponds to the position in the X direction of the imaging unit 51. Of course, the position and the number of the marks 92 may be variously changed.

The position with respect to the stage 41 of the imaging part 51 is acquired using the scale 44 beforehand. The position with respect to the stage 41 of the imaging part 51 contains the rotational position with respect to the stage 41 of the imaging part 51, ie, the rotation amount of the imaging part 51 centering on the axis | shaft toward a Z direction. This amount of rotation is a minute amount of the error degree at the time of attaching the imaging part 51 to an apparatus.

When the substrate 9 is disposed on the stage 41 so that the edge of the substrate 9 is in contact with the abutting portion 411 of the stage 41, each position of the mark 92 in the X direction is the imaging portion of which the portion is in the X direction. It almost coincides with the position in the X direction of (51). In this state, the movement of the stage 41 is started so that the board | substrate 9 may pass below the imaging part 51 (step S11). The moving direction of the stage 41 may be a (+ Y) direction or a (−Y) direction. When each mark 92 passes below any one imaging part 51, the imaging part 51 acquires several image by control of the imaging control part 211 (step S12). Thereafter, the movement of the stage 41 is stopped (step S13).

FIG. 7: is a figure which illustrates the area | regions 93a and 93b on the board | substrate 9 used as imaging object with respect to one mark 92 in step S12. When the area | regions 93a and 93b are named generically, it is called "the area | region 93." In the example of FIG. 7, three regions 93b, 93a and 93b are arranged in this order in the Y direction with respect to one mark 92. In FIG. 7, the position of the design mark 92 is shown, when there is no position shift in the board | substrate 9, and there is no deformation | transformation, such as expansion and contraction.

In the following description, the area 93a including the position of the design mark 92 is called a "first area", and the area 93b where only a part of the area overlaps the first area 93a is referred to as a "second area". do. In addition, the image which shows the 1st area | region 93a is called "1st image", and the image which shows the 2nd area | region 93b is called "2nd image". The position of the mark 92 on a design is the center of the 1st area | region 93a. The two second regions 93b are regions where only a part of the first region 93a overlaps before and after the first region 93a in the Y direction.

Each region 93 is a rectangle having long sides and short sides perpendicular to each other. The 1st area | region 93a and the 2nd area | region 93b are arranged in the direction substantially parallel to a short side. The short side is substantially parallel to the Y direction. The expression "almost parallel to the Y direction" includes the case parallel to the Y direction. The size of the region 93 is, for example, about 14 mm long and about 7 mm short. The distance between the centers of the adjacent regions 93 is about 4 mm. In FIG. 7, the region 93 is intentionally inclined with respect to the Y direction, but in reality, the tilt of the region 93, that is, the amount of rotation of the region 93, is as described above. This is the degree of error when attached to the.

By the imaging control unit 211 controlling the imaging unit 51 and the stage moving mechanism 43, imaging by the imaging unit 51 is performed without stopping the stage 41 during the movement of the stage 41. In order to realize the imaging during the movement of the stage 41, when the stage 41 passes the predetermined position, the lighting unit 53 emits light instantaneously, and the instant imaging is performed using this light. When the illumination part 53 emits light 3 times, the 2nd image, the 1st image, and the 2nd image are acquired in this order from the 2nd area | region 93b, the 1st area | region 93a, and the 2nd area | region 93b, respectively. By acquiring a plurality of images during the relative movement of the stage 41 with respect to the imaging unit 51, the plurality of images is quickly obtained.

8 is a diagram for explaining a processing state of the image synthesizing unit 212. The image synthesizing unit 212 synthesizes one first image 83a and two second images 83b to generate a synthesized image (step S14). In FIG. 8, the directions perpendicular to each other in the two-dimensional space for synthesizing the images are shown as the x direction and the y direction. The x and y directions are directions in which pixels are arranged. The x direction corresponds to the long side direction of the first image 83a and the second image 83b. The y direction corresponds to the short side directions of the first image 83a and the second image 83b.

When the 1st image 83a and the 2nd image 83b are arrange | positioned in the xy space, the Y direction of FIG. 7 corresponding to these images becomes a direction inclined by the inclination (theta) of the area | region 93. FIG. Here, as shown in FIG. 8, it is assumed that the Y direction is a direction in which the Y direction is rotated clockwise by (-θ). In addition, let d be the distance in the xy space corresponding to the distance D (see FIG. 7) between the center of the first region 93a and the center of the second region 93b. Moreover, in the XY space of FIG. 7, the y direction corresponds to the short side direction of the 1st area | region 93a and the 2nd area | region 93b, and the Y direction is a moving direction, ie, the center and the 1st direction of the 1st area | region 93a. A straight line connecting the centers of the two regions 93b corresponds. Therefore, when θ is expressed based on the region 93, θ is an angle formed by a straight line between the short side of the region 93 and the center of the region.

Since the image synthesizing unit 212 arranges the first image 83a and the second image 83b in the xy space while maintaining the relative positional relationship between the first region 93a and the second region 93b, The center of the second image 83b on the (+ y) side with respect to the center of the first image 83a is positioned on the (+ y) side by d · cosθ and on the (−x) side by d · sinθ. Similarly, the center of the second image 83b on the (−y) side with respect to the center of the first image 83a is positioned on the (−y) side by d · cosθ and on the (+ x) side by d · sinθ. Position it. Since the position of the stage 41 can be obtained accurately, the distance D and the distance d are obtained correctly. The image synthesizing unit 212 uses not only d but θ when determining the relative position of the second image 83b with respect to the first image 83a, so that the synthesis is performed with high accuracy.

As shown in FIG. 9, by design, the mark image 82 appears in the center of the first image 83a. Therefore, by overlapping the first image 83a and the second image 83b as described above, even if the mark image 82 is protruded from the first image 83a in the (± y) direction, for example, the second image The mark image 82 appears in the image 83b.

For example, as indicated by reference numeral 82a by a shift or inclination of the cutting position due to low cutting precision at the time of manufacturing the substrate 9, or by deformation such as expansion or contraction of the substrate 9, Even when all or part of the image is not shown in the first image 83a, if the mark image 82a appears in the second image 83b, the position acquiring unit 213 displays the mark image 82 in the synthesized image 85. The position of can be detected. In addition, after the synthesized image 85 is trimmed in the range shown by the broken line in FIG. 9, the mark detection processing is performed by the position acquisition unit 213. Since the position of the imaging unit 51 with respect to the stage 41 has been acquired in advance, the position acquisition unit 213 is the actual position with respect to the stage 41 based on the position of the mark image 82 in the composite image 85. The position of the mark 92 can be detected (step S15).

In this way, in the drawing device 1, by using the synthesized image 85, the field of view can be easily enlarged without lowering the resolution of the imaging unit 51, and the detection error at the position of the mark 92 can be reduced. . Moreover, since the imaging part 51 is arrange | positioned so that the short side of the area | region 93 may become substantially parallel to a Y direction, the width | variety of the x direction of the synthesize | combination image 85 is ensured, and the synthesize | combination image 85 is made close to a large square. easy. Thereby, it becomes easy to make the mark 92 fall into a visual field when the mark 92 shifts from a design position.

As shown in FIG. 9, the image synthesizing unit 212 preferentially synthesizes the first image 83a in a region where the first image 83a and the second image 83b overlap. That is, the pixel value of the site | part where the 1st image 83a and the 2nd image 83b overlap in the synthesized image 85 becomes the pixel value of the 1st image 83a. As a process of first synthesizing the first image 83a, the first image 83a may be overwritten after the second image 83b is written into the memory space, and the image to be written for each pixel of the memory space is sequentially. May be selected.

Since the mark image 82 appears in the center of the first image 83a by design, the probability that the mark image 82 actually appears is higher in the first image 83a than in the second image 83b. Therefore, by using the first image 83a preferentially over the second image 83b, the probability that the mark image 82 overlaps with the boundary of the synthesis in the synthesized image 85 can be lowered. As a result, the mark image 82 tends to appear neatly in the synthesized image 85, and a decrease in the detection accuracy at the position of the mark 92 can be suppressed.

In the example of FIGS. 7-9, although three images are acquired during the relative movement of the stage 41 with respect to the imaging part 51, the number of images is not limited to three. Preferably, the imaging part 51 acquires the image of the odd multiple area arrange | positioned in the movement direction, and each of the some area overlaps only an area and a part adjacent. At this time, the design position of the mark image 82 is set to the center of the center image corresponding to the above-mentioned first image 83a. In addition, similarly to the case of FIG. 8, in the synthesized image, the pixel value of the portion where the center image and another adjacent image overlap is the pixel value of the center image. Thereby, the possibility that the mark image 82 spreads over two images can be reduced. Even when a large number of images are acquired for one mark 92, since the images are acquired during the movement of the substrate 9, the time required for image acquisition is the same as when only one image is acquired. The area where the adjacent areas 93 overlap is preferably 1/10 or more and 1/3 or less of the area 93.

As shown in FIG. 2, when the drawing apparatus 1 has three imaging sections 51, and as shown in FIG. 6, nine marks 92 are arranged in three rows and three columns on the substrate 9. While the stage 41 moves in the Y direction once by the stage moving mechanism 43, each imaging unit 51 acquires the mark image 82 three times. In acquiring each mark image, multiple imaging is performed as mentioned above, and image synthesis | combination is performed. Thereby, nine mark images 82 are obtained at high speed.

At this time, by the imaging control part 211 and the stage movement mechanism 43 by the imaging control part 211, each imaging part 51 acquires an image similarly. For example, when one 1st image 83a and two 2nd image 83b shown in FIG. 8 are acquired by one imaging part 51, one imaging agent 51 similarly uses the 1st image. One image 83a and two second images 83b are obtained. After the synthesis by the image synthesizing unit 212, the synthesized image 85 is trimmed to the same size. Thereby, nine synthesized images 85 of the same size corresponding to nine marks 92 are obtained. Regardless of the kind or size of the mark 92, by making the plurality of composite images 85 the same size, most of the detection processing of the position of the mark 92 becomes common, and the creation and detection of the detection program becomes easy.

The drawing apparatus 1 can be variously modified.

One second image 83b may be provided. In this case, the number of images acquired with respect to one mark 92 is two. Preferably, the number of images acquired with respect to one mark 92 is three or more. Preferably, the number of images acquired is an odd number of 3 or more, but may be an even number.

When the image is acquired, the movement of the stage 41 may be stopped. That is, the process of acquiring the 1st image 83a and the process of acquiring the 2nd image 83b do not need to be performed continuously. When the stage 41 is stopped at the time of imaging, an inexpensive one can be employed as the imaging unit 51. The first region 93a and the second region 93b may be arranged in the X direction, that is, in a direction perpendicular to the moving direction of the stage 41. In this case, a moving mechanism for moving the imaging unit 51 or the stage 41 with high accuracy in the X direction is formed. Further, four second regions 93b may be set at the front, rear, left, and right positions with respect to the first region 93a, and eight second regions 93b are positioned at eight vicinity with respect to the first region 93a. It may be set.

When the pixels of the image sensor of the imaging unit 51 are exactly arranged in the XY direction, the angle θ formed by the Y direction and the y direction becomes 0 when synthesizing the images, and the angle θ need not be considered. At the time of image synthesis, the first image 83a is not given priority but may be synthesized by simply overwriting in accordance with the imaging order.

The mark 92 need not be a dedicated alignment mark. For example, via holes and characteristic patterns formed in the substrate 9 may be used as the marks 92 by the imaging unit 51.

The stage 41 does not need to determine the position of the substrate 9 by the abutting portion 411. For example, the stage 41 may hold the end of the substrate 9. The substrate 9 may be simply placed.

Instead of the stage moving mechanism 43, a moving mechanism for moving the imaging unit 51 in a straight line with respect to the stage 41 in a direction parallel to the main surface of the substrate 9 may be formed. The movement of the stage 41 with respect to the imaging part 51 should just be relative.

The arrangement of the marks 92 may be appropriately changed. Preferably, the imaging part 51 is arrange | positioned in each position of the mark 92 in the X direction. Of course, the number of the X direction positions of the mark 92 may be larger than the number of the imaging sections 51. In this case, after the movement and imaging of the Y-direction of the stage 41 are completed, the imaging is performed while the imaging unit 51 is moved to the X-direction and the stage 41 is moved again to the Y-direction.

The process of detecting the position of the mark image 82 from the synthesized image 85 may be performed sequentially for each mark 92, or a parallel process may be performed.

The light emitted from the drawing head 31 may be one light beam that is simply ON / OFF modulated.

In the drawing apparatus 1, the moving mechanism which moves the drawing head 31 to a moving direction may be formed. That is, in the drawing apparatus 1, the moving mechanism which moves the stage 41 continuously with respect to the drawing head 31, and in a moving direction is formed.

The board | substrate 9 in which a pattern is drawn may be a semiconductor substrate, a glass substrate, etc. other than a printed wiring board. The substrate 9 is preferably a substrate having flexibility, but is not limited to the printed wiring board.

The configurations in the above embodiments and each modification may be appropriately combined so long as they do not contradict each other.

While the invention has been described and described in detail, the foregoing description is illustrative only and not restrictive. Therefore, many variations and aspects are possible without departing from the scope of the present invention.

1: drawing device (mark position detection device)
8: writing data
9: substrate
31: drawing head
41: stage
43: stage moving mechanism
51: imaging unit
83a: first image
83b: second image
85: composite image
92: Mark
93a: first zone
93b: second area
211: imaging control unit
212: image synthesis unit
213: position acquisition unit
214: correction unit
215: drawing control unit
S11-S15: step

Claims (10)

A mark position detection device for detecting the position of a mark on a substrate held in a stage,
A stage holding the substrate,
An imaging unit for acquiring an image of a mark formed on the substrate;
A moving mechanism for relatively moving the stage with respect to the imaging unit in a direction parallel to a main surface of the substrate;
By controlling the said imaging part and the said moving mechanism, the 1st image which shows the 1st area | region on the said board | substrate containing the design position of the said mark, and the 2nd image which shows the 2nd area which only a part overlaps with the said 1st area | region An imaging control unit to acquire,
An image synthesizer which synthesizes the first image and the second image to generate a synthesized image;
And a position acquiring unit for obtaining a position of the mark with respect to the stage based on the synthesized image. The method of claim 1,
Each of the first region and the second region has a long side and a short side perpendicular to each other,
And the first region and the second region are arranged in a direction substantially parallel to the short side. The method of claim 2,
The image synthesizing unit is adapted to determine the relative position of the second image with respect to the first image, the short sides of the first region and the second region, the center of the first region, and the center of the second region. Mark position detection apparatus using the angle formed by the connecting straight line. The method of claim 1,
The moving mechanism moves the stage relative to the imaging unit in a direction of movement relative to the straight line,
And the imaging unit acquires the first image and the second image during relative movement of the stage with respect to the imaging unit. The method of claim 1,
The moving mechanism moves the stage relative to the imaging unit in a direction of movement relative to the straight line,
The imaging unit acquires images of an odd number of plural regions arranged in the moving direction, each of the plural regions overlaps only an area with an adjacent region,
The first area is an area in the center of the plurality of areas,
And said second area is one area adjacent to said first area. The method of claim 1,
The mark position detection apparatus according to claim 1, wherein the pixel value of a portion where the first image and other images in the composite image overlap is a pixel value of the first image. The method of claim 1,
Another imaging part which acquires the image of the other mark formed on the said board | substrate is further provided,
The imaging control section controls the other imaging section and the moving mechanism so that only another first image representing another first area on the substrate including a design position of the other mark, and the other first area and a part thereof. Acquire another second image representing another overlapping second region,
The image synthesizing unit synthesizes the other first image and the other second image to generate another synthesized image,
A mark position detection device, wherein the size of the synthesized image is the same as the size of the other synthesized image. The method of claim 1,
A mark position detection device, wherein the substrate is flexible. As a drawing device for drawing a pattern on a substrate,
The mark position detection apparatus in any one of Claims 1-8 which detects the several mark position formed on the board | substrate,
A correction unit that corrects drawing data based on the plurality of mark positions;
A writing head for irradiating the modulated light to the substrate on the stage;
And a drawing control unit that executes drawing on the substrate based on the corrected drawing data by controlling the moving mechanism and the drawing head. A mark position detection method for detecting the position of a mark on a substrate held on a stage,
a) a process of acquiring a first image representing a first area including a design position of a mark on a substrate held on a stage;
b) acquiring a second image representing a second region in which only a part of the first region overlaps;
c) synthesizing the first image and the second image to generate a composite image;
and d) obtaining a position of the mark relative to the stage based on the synthesized image.

Images