JP2010243205A - Substrate state inspection method, laser beam machining device, and method for manufacturing solar panel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To inspect chip or bending (warpage) of a substrate to be carried into a laser beam machining spot. <P>SOLUTION: When carrying the substrate into a machining spot, images around four corners of the substrate or images of an outer peripheral edge of the substrate are acquired, to thereby detect bending (warpage) of the substrate or chip on the periphery of the four corners or on the outer peripheral edge of the substrate based on the images. Since a relative position relation of a camera means for acquiring the images around the four corners or the outer peripheral edge of the substrate has a known value set beforehand, when a position of each vertex is deviated in the image of each vertex of the four corners, the bending (warpage) of the substrate can be detected based on a deviation amount, and chip of the substrate can be also detected based on the images around the four corners. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a laser processing method and apparatus for processing a thin film or the like using a laser beam, and a solar panel manufacturing method, and more particularly to a substrate state inspection method and laser processing apparatus for inspecting the state of a substrate carried into a laser processing location, and The present invention relates to a solar panel manufacturing method.

  Conventionally, in a solar panel manufacturing process, a transparent electrode layer, a semiconductor layer, and a metal layer are sequentially formed on a translucent substrate (glass substrate), and each layer is processed into a strip shape with laser light in each step after the formation. A solar panel module has been completed. When forming a scribe line with a laser beam, the laser beam is usually irradiated onto a glass substrate that moves at a constant speed. Thereby, it is possible to form a scribe line having a stable depth and line width. In such a method of manufacturing a solar panel (photoelectric conversion device), a substrate that is a glass substrate must be accurately aligned in the laser processing apparatus. Further, it is necessary to inspect the glass substrate for any chipping or bending. As a method for aligning a glass substrate, a method as described in Patent Document 1 is known.

JP 2001-232486 A

  In the device described in Patent Document 1, the substrate is abutted and fixed at a predetermined position using a positioning pin that moves up and down in a state where the glass substrate is placed. However, when manufacturing a solar panel, scribe lines are formed on a thin film on a glass substrate at a pitch of 10 mm, for example, and the scribe lines have a line width of about 30 μm and a line-to-line spacing of about 30 μm. It is composed of lines. Therefore, in the positioning by abutment as in Patent Document 1, the lines overlap each other, and it is difficult to form a desired scribe line. Conventionally, alignment was performed, but the glass substrate was not inspected for chipping or bending (warping), so a solar panel module was formed on the glass substrate having chipping or bending (warping). It was.

  The present invention has been made in view of the above points, and a substrate state inspection method, a laser processing apparatus, and a solar panel manufacturing method capable of inspecting chipping or bending (warping) of a substrate carried into a laser processing location. Is to provide.

A first feature of the substrate state inspection method according to the present invention is that, when a substrate is carried into a processing position by a laser beam, images near the four corners of the substrate are acquired, and the substrate is bent (warped) based on the image. ) And the detection of chips near the four corners of the substrate.
Processing with laser light is performed by irradiating the processing surface of the substrate substantially perpendicularly with laser light emitted from a laser generator. Therefore, if the substrate is bent (warped) or the four corners of the substrate are missing, it is difficult to perform accurate processing, which may cause a problem in the quality of the solar panel module. Therefore, in the present invention, when the substrate is carried into the processing position, images near the four corners of the substrate are acquired, and bending (warping) of the substrate or chipping near the four corners of the substrate is detected based on the image. . Since the relative positional relationship of the camera means for acquiring images near the four corners of the board is a known value set in advance, if the position of each vertex is shifted in the image of each vertex at the four corners, the amount of shift It is possible to detect the bending (warping) of the substrate based on the above, and it is also possible to detect the chipping of the substrate based on the images near the four corners.

  According to a second aspect of the substrate state inspection method of the present invention, in the substrate state inspection method according to the first feature, acquisition of images near the four corners of the substrate is provided corresponding to the four corners of the substrate. This is done by using four image acquisition means. In this method, images near the four corners of the substrate are acquired using four image acquisition means (for example, camera means) provided on the upper or lower side of the substrate, respectively. By moving these four image acquisition means along the four sides of the substrate, it is possible to detect a chip in the outer peripheral edge of the substrate.

A third feature of the substrate state inspection method according to the present invention is that an image of the outer peripheral edge of the substrate is acquired when the substrate is carried into a processing position by laser light, and the substrate is bent (warped) based on the image. ) And detecting a chip in the outer peripheral edge of the substrate.
In this method, when the substrate is carried into the processing position, an image of the outer peripheral edge of the substrate is acquired, and bending (warping) of the substrate or chipping of the outer peripheral edge of the substrate is detected based on the image. . In order to acquire an image of the outer peripheral edge of the substrate, an image path acquisition unit that moves along the outer peripheral edge of the substrate may be provided. In this case, one or a plurality of image acquisition means may be moved along the outer peripheral edge of the substrate.

  According to a fourth aspect of the substrate state inspection method of the present invention, in the substrate state inspection method according to the third aspect, acquisition of an image of the outer peripheral edge of the substrate is performed at each diagonal of the outer peripheral edge of the substrate. There are two image acquisition means provided correspondingly. In this method, the image of the outer peripheral edge of the substrate is acquired using two image acquisition means (for example, camera means) provided on the upper or lower side of the substrate, respectively. The two image acquisition means acquire an image of a side (a part of the outer peripheral edge) parallel to the movement direction of the substrate by using the movement of the substrate, and move the substrate in a direction perpendicular to the movement direction of the substrate. An image of each side (part of the outer peripheral edge) parallel to the direction perpendicular to the moving direction is acquired, and the bending (warping) of the substrate and the chip of the outer peripheral edge of the substrate are detected based on the images. It is.

  The first feature of the laser processing apparatus according to the present invention is that a carry-in means for holding a substrate and carrying it into a machining position by laser light, a holding means for holding the substrate carried by the carry-in means, and the holding means Laser light irradiation means for irradiating the held substrate with laser light to perform predetermined processing, image acquisition means for acquiring images near the four corners of the substrate held by the carry-in means, and the image acquisition means And detecting means for detecting bending (warping) of the substrate and chipping near the four corners of the substrate based on the images near the four corners of the substrate acquired by the above. This is an invention of a laser processing apparatus using the one described in the first feature of the substrate state inspection method.

  A second feature of the laser processing apparatus according to the present invention is the laser processing apparatus according to the first feature, wherein the image acquisition means is configured by camera means for acquiring images near the four corners of the substrate. There is. This is an invention of a laser processing apparatus using the one described in the second feature of the substrate state inspection method.

  A third feature of the laser processing apparatus according to the present invention is that a carry-in means for holding a substrate and carrying it into a processing position by laser light, a holding means for holding the substrate carried by the carry-in means, and the holding means Laser light irradiation means for irradiating the held substrate with laser light to perform a predetermined processing, image acquisition means for acquiring an image of the outer periphery of the substrate held by the carry-in means, and the image acquisition means And detecting means for detecting bending (warping) of the substrate and chipping of the outer peripheral edge of the substrate on the basis of the image obtained by the above. This is an invention of a laser processing apparatus using the one described in the third feature of the substrate state inspection method.

  According to a fourth aspect of the laser processing apparatus of the present invention, in the laser processing apparatus according to the third aspect, the image acquisition unit is provided corresponding to each diagonal of the outer peripheral edge of the substrate. It consists of two camera means. This is an invention of a laser processing apparatus using the one described in the fourth feature of the substrate state inspection method.

  The feature of the solar panel manufacturing method according to the present invention is any one of the substrate state inspection method according to any one of the first feature to the fourth feature or the first feature to the fourth feature. A solar panel is manufactured using the laser processing apparatus described in 1). In this method, a solar panel is manufactured using any one of the substrate state inspection method and the laser processing apparatus.

  ADVANTAGE OF THE INVENTION According to this invention, there exists an effect that the chip | tip and bending (warp) of the board | substrate carried in to a laser processing location can be test | inspected.

It is a figure which shows schematic structure of the laser processing apparatus which concerns on one embodiment of this invention. It is a figure which shows the relationship between a board | substrate detection camera and a board | substrate. It is a figure which shows another relationship between a board | substrate detection camera and a board | substrate. It is a figure which shows the concept of the board | substrate alignment method which aligns a board | substrate on the XY table of FIG. 1, and is a figure which shows the Iran met process before the first scribe process. It is a figure which shows the concept of the substrate alignment method which aligns a board | substrate on the XY table of FIG. 1, and is a figure which shows the alignment process before the scribe process of the 2nd time or later. It is a figure which shows the detailed structure of the optical system member of FIG. It is a schematic diagram which shows the structure of the detection optical system member of FIG. It is a block diagram which shows the detail of a process of a control apparatus. It is a figure which shows an example of operation | movement of the pulse missing determination means of FIG. It is a figure which shows an example of the waveform output from the high-speed photodiode of FIG. It is the figure which looked at the optical system member of FIG. 1 from the lower side (board | substrate side). It is a figure which shows the relationship between the rotation amount of an optical system member, and the pitch width of a scribe line.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a diagram showing a schematic configuration of a laser processing apparatus equipped with a substrate state inspection apparatus according to an embodiment of the present invention. This laser processing apparatus performs a laser beam processing (laser scribing) process of a solar panel manufacturing apparatus.

  1 includes a pedestal 10, an XY table 20, a laser generator 40, an optical system member 50, an alignment camera device 60, substrate detection cameras 65 to 68, a linear encoder 70, a control device 80, and a first detection. It is comprised by the optical system member, the 2nd detection optical system member, etc. An XY table 20 that is driven and controlled along the X-axis direction and the Y-axis direction (XY plane) of the pedestal 10 is provided on the pedestal 10.

  The XY table 20 is controlled to move in the X direction and the Y direction. In addition, although a ball screw, a linear motor, etc. are used as a drive means of the XY table 20, these illustration is abbreviate | omitted. On the upper side of the XY table 20, a substrate 1 to be laser processed is held. A slide frame 30 that is slid in the Y-axis direction while holding the optical system member is provided on the base 10. The XY table 20 is configured to be rotatable in the θ direction about the Z axis. Note that when the amount of movement in the Y-axis direction can be sufficiently secured by the slide frame 30, the XY table 20 may be configured to only move in the X-axis direction. In this case, the XY table 20 may have an X-axis table configuration.

  The slide frame 30 is attached to a movable table provided at four corners on the base 10. The slide frame 30 is controlled to move in the Y direction by this moving table. A vibration isolation member (not shown) is provided between the base plate 31 and the moving table. A laser generator 40, an optical system member 50, and a control device 80 are installed on the base plate 31 of the slide frame 30.

  The alignment camera device 60 acquires images on the XY table 20 and in the vicinity of both ends (front and rear edges in the X-axis direction) of the substrate 1. An image acquired by the alignment camera device 60 is output to the control device 80. The control device 80 stores the image from the alignment camera device 60 in the database unit together with the ID data of the substrate 1 and uses it for the subsequent alignment processing of the substrate 1.

  2 is a diagram illustrating a relationship between the substrate detection camera and the substrate, and FIG. 2A is a side view illustrating a relationship between the substrate mounted on the moving table and the substrate detection camera, and FIG. (B) is a top view thereof. The substrate detection cameras 65 to 68 acquire images near the four corners of the substrate 1 from the upper side when the substrate 1 placed on the movable table 24 is put on the XY table 20. In FIG. 2, the substrate 1 is placed on the moving table 24, moved from the left side to the right side, and immediately before being put on the XY table 20. Images 65 a to 68 a shown in FIG. 2B are images near the four corners of the substrate 1 acquired by the substrate detection cameras 65 to 68. Since the relative positional relationship of the board detection cameras 65 to 68 is a known value set in advance, as shown in the images 65a to 68a, each vertex of the four corners of the board 1 without warping or bending is set to the board detection camera 65 to 65. It is set so as to be located near the center of the 68 imaging range. Therefore, when the positions of the vertices are deviated in the images 65a to 68a, the bending (warping) of the substrate 1 can be detected based on the deviation amount. Further, it is possible to detect a chip near the four corners of the substrate 1 based on the images 65a to 68a. Note that chipping of each side of the substrate 1 can be detected by moving the substrate detection cameras 65 to 68 along each side of the substrate 1.

  FIG. 3 is a diagram illustrating another relationship between the substrate detection camera and the substrate. In the above-described embodiment, the substrate detection cameras 65 to 68 are provided in the upper part near the four corners of the substrate 1. However, in this embodiment, the two substrate detection cameras 65 and 68 are near the diagonal of the substrate 1. It is located on the upper side. In FIG. 3A, in a state where the substrate 1 is placed on the moving table 24, the substrate 1 indicated by the dotted line moves to the right as indicated by the arrow from the position and the position of the substrate 1 indicated by the solid line (substrate 1). To a position where the substrate detection cameras 65 and 68 are located on the upper side of the diagonal. During the movement of the substrate 1, the substrate detection camera 68 acquires an image of the side 1 a of the moving substrate 1. Then, at the end of the substrate movement, the substrate detection cameras 65 and 68 acquire the images of the apexes near the diagonal of the substrate 1 (images 65a and 68a in FIG. 2). With the substrate 1 stopped, the substrate detection cameras 65 and 68 are now moved along the dotted arrows as shown in FIG. When the substrate detection cameras 65 and 68 are moved, the substrate detection camera 65 acquires an image of the side 1b of the substrate 1, and the substrate detection camera 68 acquires an image of the side 1c of the substrate 1. At the end of the movement of the substrate detection cameras 65 and 68, the substrate detection cameras 65 and 68 acquire images of vertices near another diagonal of the substrate 1 (images 66a and 67a in FIG. 2). With the substrate detection cameras 65 and 68 stopped, the substrate 1 this time, as shown in FIG. 3C, the substrate 1 indicated by the dotted line moves to the right as indicated by the arrow from the position, and the substrate 1 indicated by the solid line Move to the position. During the movement of the substrate 1, the substrate detection camera 65 acquires an image of the side 1 d of the moving substrate 1. Through the above-described series of operations, the images 65a to 68a and the image of each side of the substrate 1 can be acquired using the two substrate detection cameras 65 and 68 as in the case of FIG. Thereby, it is possible to detect the bending (warping) of the substrate 1 and the chipping of each side of the substrate 1 based on the shift amount of the position of each vertex of the images 65a to 68a. Note that the substrate detection cameras 65 and 68 may be returned to the initial positions shown in FIG. 3A after a series of detection operations, or the reverse operation may be performed without returning them.

  The linear encoder 70 includes a scale member and a detection unit provided on the side surface of the X-axis movement table of the XY table 20. The detection signal of the linear encoder 70 is output to the control device 80. The control device 80 detects the moving speed (moving frequency) in the X-axis direction of the XY table 20 based on the detection signal from the linear encoder 70, and controls the output (laser oscillation frequency) of the laser generator 40.

  The optical system member 50 is constituted by a combination of a mirror and a lens, and divides the laser beam generated by the laser generator 40 into four lines and guides it onto the substrate 1 on the XY table 20. In FIG. 1, the optical system member 50 is provided on the side surface side of the base plate 31 and is configured to move along the side surface of the base plate 31. A mirror 33 for guiding laser light emitted from the laser generator 40 to the optical system member 50 is provided on the base plate 31. The mirrors 34 and 35 are provided on the optical system member 50 and are interlocked with the slide movement of the optical system member 50. The laser beam emitted from the laser generator 40 is reflected by the mirror 33 toward the mirror 34, and the laser beam toward the mirror 34 is reflected by the mirror 34 toward the mirror 35. The mirror 35 guides the reflected laser light from the mirror 34 into the optical system member 50 through a through hole provided in the base plate 31. The laser light emitted from the laser light generating device 40 may have any configuration as long as the laser light is configured to be introduced from above into the optical system member 50 through a through hole provided in the base plate 31. It may be. For example, the laser generator 40 may be provided on the upper side of the through hole, and the laser beam may be directly guided to the optical system member 50 through the through hole. In this embodiment, the number of divisions of laser light is described as four series, but the number of divisions is not limited to this, and may be two or more.

  4 and 5 are views showing the concept of the substrate alignment method for aligning the substrate on the XY table of FIG. 1, FIG. 4 shows the island met process before the first scribe process, and FIG. 5 shows the second and subsequent times. It is a figure which shows an example of the alignment process before a scribe process, respectively. First, as shown in FIG. 4, with the substrate 1 placed, the lower edge of the left end of the substrate 1 is the positioning pin 21, the left edge of the lower end of the substrate 1 is the positioning pin 22, The right edge of the lower end of the substrate 1 is abutted against the positioning pins 23 to position the substrate 1 at a predetermined position on the XY table 20. In this state, the transparent electrode layer on the substrate 1 is irradiated with laser light to execute a scribing process. As a result of the initial scribing process, scribe lines are formed on the substrate 1 with a pitch of 10 mm.

  FIG. 4 shows one scribe line 25 near the center of the substrate among the plurality of scribe lines. Images 27a and 29a in the vicinity of both ends of the scribe line 25, that is, in the vicinity of locations 27 and 29 including both the scribe line 25 and the edge of the substrate 1, are acquired by the alignment camera device 60 described above. As can be seen from the images 27a and 29a, since both the image of the scribe line 25 and the image of the shape of the edge of the substrate 1 are included in the image, the image recognition process is facilitated. The acquired images 27a and 29a are sequentially stored in the database means 75 as ID data of the substrate 1 by the control device.

  As shown in FIG. 4, when the acquisition process of the images 27a and 29a is completed together with the scribing process by laser processing, the process of forming a semiconductor layer on the transparent electrode layer is performed next. After the completion of the semiconductor layer forming process, a scribing process using laser light similar to that described above is performed on the substrate 1. Prior to the second scribing process, an alignment process is performed as shown in FIG.

  In FIG. 5, the lower edge of the left end of the substrate 1 is positioned on the positioning pin 21 and the left edge of the lower end of the substrate 1 is positioned in the state where the substrate 1 is placed as in the first alignment process. The right edge of the lower end of the substrate 1 is brought into contact with the positioning pins 23 to the pins 22 to position the substrate 1 at a predetermined position on the XY table 20. In this state, the alignment camera device 60 acquires images 27b and 29b in the vicinity of both ends of the scribe line 25, that is, in the vicinity of locations 27 and 29 including both the scribe line 25 and the edge of the substrate 1. On the other hand, the control device reads the images 27a and 29a of the ID data of the substrate 1 from the database means 75. The read images 27a and 29a are compared with the images 27b and 29b acquired by the alignment camera device 60 by the control device, and the X-axis, Y-axis, and θ-axis of the XY table 20 are matched so that they match. Are controlled, and an accurate alignment process is performed.

  As shown in FIG. 5, when the alignment process by the comparison process of the images 27a and 29a and the images 27b and 29b is completed, the scribing process by the laser beam is executed at a position about 30 μm away from the previous scribe line 25. When this scribing process is completed, a process for forming a metal layer on the semiconductor layer is performed by another apparatus. Again, the substrate is carried into the laser processing apparatus, alignment processing similar to that shown in FIG. 5 is performed, and scribing processing using laser light is similarly performed on the substrate 1. As a result, three scribe lines are formed on the substrate 1.

  In the above-described embodiment, the case where an image including a scribe line formed on the substrate 1 is acquired as a result of the first scribe process has been described. However, the image formed on the substrate 1 as a result of the second scribe process. An image including two scribe lines may be acquired and used for alignment processing. In the above-described embodiment, the case where the alignment camera device 60 and the substrate detection cameras 65 to 68 are separately provided has been described. However, the alignment camera device 60 is provided with a moving mechanism as shown in FIG. You may make it share the function of 65-68.

  FIG. 6 is a diagram showing a detailed configuration of the optical system member 50. Although the actual configuration of the optical system member 50 is complicated, the illustration is simplified here for the sake of simplicity. 6 is a view of the inside of the optical system member 50 as viewed from the −X axis direction of FIG. As shown in FIG. 6, the base plate 31 has a through hole 37 for introducing the laser beam reflected by the mirror 35 into the optical system member 50. A phase type diffractive optical element (DOE) 500 that converts laser light having a Gaussian intensity distribution into laser light having a top hat intensity distribution is provided directly below the through hole 37.

  The laser light converted into laser light having a top hat intensity distribution (top hat beam) by the DOE 500 is branched into a reflected beam and a transmitted beam by the half mirror 511, and the reflected beam is transmitted to the right half mirror 512. Advances toward the reflective mirror 524 in the downward direction. The beam reflected by the half mirror 511 is further split into a reflected beam and a transmitted beam by the half mirror 512, and the reflected beam travels toward the lower reflecting mirror 522, and the transmitted beam travels toward the right reflecting mirror 521. The beam that has passed through the half mirror 512 is reflected by the reflection mirror 521, and is irradiated onto the substrate 1 through the condensing lens 541 in the downward direction. The beam reflected by the half mirror 512 is reflected by the reflection mirrors 522 and 523 and is irradiated onto the substrate 1 through the condensing lens 542 in the downward direction. The beam transmitted through the half mirror 511 is reflected by the reflection mirror 524 and travels in the left direction. The beam reflected by the reflection mirror 524 is branched into a reflection beam and a transmission beam by the half mirror 513, the reflection beam travels toward the reflection mirror 526 in the downward direction, and the transmission beam travels toward the reflection mirror 528 in the left direction. The beam reflected by the half mirror 513 is reflected by the reflection mirrors 526 and 527 and is irradiated onto the substrate 1 through the condensing lens 543 in the downward direction. The beam that has passed through the half mirror 513 is reflected by the reflection mirror 528, and is applied to the substrate 1 through the condensing lens 544 in the downward direction.

  The top hat beam converted by the DOE 500 is transmitted and reflected by the above-described half mirrors 511 to 513 and the reflection mirrors 521 to 528 and guided to the condenser lenses 541 to 544. At this time, the optical path lengths from the DOE 500 to the condenser lenses 541 to 544 are set to be equal. That is, the optical path length from when the beam reflected by the half mirror 511 passes through the half mirror 512 and is reflected by the reflection mirror 521 to reach the condenser lens 541, and the beam reflected by the half mirror 511 is the half mirror 512 and the reflection mirror 522. , 523, the optical path length until reaching the condenser lens 542, and the beam transmitted through the half mirror 511 are reflected by the reflection mirror 523, the half mirror 513, the reflection mirrors 526 and 527, respectively, and enter the condenser lens 543. The optical path length until the beam reaches the condensing lens 544 is reflected by the reflection mirror 523, reflected by the reflection mirror 523, reflected by the reflection mirror 528, and reaches the condenser lens 544, respectively. Are equal distances. Accordingly, even if the DOE 500 is arranged immediately before the beam is branched, the laser light having the top hat intensity distribution can be similarly guided to the condenser lenses 541 to 544.

  The shutter mechanisms 531 to 534 block the emission of laser light when the laser light emitted from the condenser lenses 541 to 544 of the optical system member 50 is detached from the substrate 1. The autofocus length measuring systems 52 and 54 include a detection light irradiation laser and an autofocus photodiode (not shown), and are reflected from the surface of the substrate 1 in the light irradiated from the detection light irradiation laser. The reflected light is received, and the condensing lenses 541 to 544 in the optical system member 50 are driven up and down in accordance with the amount of the reflected light to adjust the height relative to the substrate 1 (the focus of the condensing lenses 541 to 544). The focus adjustment drive mechanism is not shown.

  FIG. 7 is a schematic diagram showing the configuration of the first detection optical system member and the second detection optical system member. The first detection optical system member includes a condenser lens height measurement system 26 and a focus and optical axis adjustment CCD camera 28. In FIG. 7, since the condenser lens height measuring system 26 and the CCD camera 28 for focusing and optical axis adjustment are shown overlappingly, they are distinguished by reference numerals. When the height from the substrate 1 to the lower surfaces on both sides of the optical system member 50 is adjusted by the autofocus length measuring systems 52 and 54 shown in FIG. 6, the height of the lower surface of the optical system member 50 is the same. Even if it can, the height from the board | substrate 1 to each condensing lens 541-544 cannot necessarily be made the same. Therefore, in this embodiment, the condenser lens height measuring system 26 is attached to either one of the side surfaces in the X axis direction of the XY table 20 (the side surface in the −X axis direction of the XY table 20 in the figure), and the substrate 1 To the condensing lenses 541 to 544, respectively. A signal corresponding to the height of each of the condenser lenses 541 to 544 detected by the condenser lens height measuring system 26 is output to the control device 80. The control device 80 determines whether or not the height from the substrate 1 to each of the condenser lenses 541 to 544 is appropriate. The arrangement (height) of the condenser lenses 541 to 544 is adjusted according to the length measurement result of the condenser lens height measuring system 26. In this case, the arrangement (height) of the condenser lenses 541 to 544 can be adjusted manually or automatically.

  The focus and optical axis adjusting CCD camera 28 is one of the side surfaces in the X-axis direction of the XY table 20 (the side surface in the −X-axis direction of the XY table 20 in the figure), and is a condensing lens height measuring system. 26 adjacent positions (neighboring). The CCD camera 28 for focus and optical axis adjustment associates the positions of the XY table 20 and the respective condensing lenses 541 to 544 of the optical system member 50 and is installed so that the sky side of the XY table 20 can be seen. . The image captured by the focus and optical axis adjusting CCD camera 28 is output to the control device 80. The control device 80 determines whether or not the optical axis of the laser light emitted from each of the condenser lenses 541 to 544 is appropriate. In other words, the focus and optical axis adjusting CCD camera 28 can directly observe the laser light emitted from the respective condensing lenses 541 to 544 of the optical system member 50. By imaging this, the control device 80 Can determine whether the focus and the optical axis of each of the condenser lenses 541 to 544 are appropriate. Further, when each optical system related to the laser beam such as the laser generator 40 and the optical system member 50 is replaced, the images before and after the replacement are acquired and digitized so that the focus and the optical axis after the replacement are obtained. Adjustment can be performed easily. Further, in the case of a plurality of heads, variation can be appropriately adjusted by acquiring and digitalizing images of the respective laser beams.

  As shown in FIG. 1, the second detection optical system member includes beam samplers 92 and 93, a high-speed photodiode 94, and an optical axis inspection CCD camera 96. The beam samplers 92 and 93 are provided in the optical path of laser light introduced into the optical system member 50. In this embodiment, it is provided between the laser generator 40 and the reflection mirror 33. The beam samplers 92 and 93 are elements that sample a part of the laser beam (for example, about 10% of the laser beam or less) and branch and output it to the outside. The high-speed photodiode 94 is disposed so as to receive a part (sampling beam) of the laser beam branched and output by the beam sampler 92 near the center of the light receiving surface. An output signal corresponding to the intensity of the laser light detected by the high speed photodiode 94 is output to the control device 80. The optical axis inspection CCD camera 96 is arranged so as to receive a part (sampling beam) of the laser beam branched and output by the beam sampler 93 near the center of the light receiving surface. The image captured by the optical axis inspection CCD camera 96 is output to the control device 80. The optical axis inspection CCD camera 96 may capture an image indicating the position of the laser light applied to the high-speed photodiode 94 and output the image to the control device 80.

  The control device 80 detects the moving speed (moving frequency) in the X-axis direction of the XY table 20 based on the detection signal from the linear encoder 70, controls the output (laser frequency) of the laser generator 40, and the condenser lens. Based on the signals output from the height measurement system 26, the focus and optical axis adjustment CCD camera 28, the high-speed photodiode 94, and the optical axis inspection CCD camera 96, from the substrate 1 to the condenser lenses 541 to 544. Of the laser beam emitted from the laser generator 40, whether the focus and the optical axis of each of the condenser lenses 541 to 544 are appropriate, Detection of pulse omission, control of the emission conditions of the laser generator 40 based on the substrate processing state such as the amount of optical axis deviation of the laser beam, and laser in the optical system member 50 Or feedback control of the arrangement of the reflecting mirrors 33 to 35 for the introduction of, or adjust the arrangement of the condenser lens 541 to 544.

  FIG. 8 is a block diagram showing details of processing of the control device 80. The control device 80 includes a branching unit 81, a missing pulse determining unit 82, an alarm generating unit 83, a reference CCD image storage unit 84, an optical axis deviation measuring unit 85, a laser controller 86, a lens displacement measuring unit 87, and a lens height adjustment. It comprises means 88, irradiation laser state inspection means 89, and irradiation laser adjustment means 8A.

  The branching unit 81 branches the detection signal (clock pulse) of the linear encoder 70 and outputs it to the laser controller 86 at the subsequent stage. The pulse missing determination means 82 receives an output signal (diode output) corresponding to the laser light intensity from the high-speed photodiode 94 and a detection signal (clock pulse) output from the branching means 81, and based on this, the laser light Determine missing pulses. FIG. 9 is a diagram illustrating an example of the operation of the missing pulse determination unit 82. 9A is an example of a detection signal (clock pulse) output from the branching means 81, and FIG. 9B is an output signal corresponding to the laser light intensity output from the high-speed photodiode 94 (diode). FIG. 9C shows an example of an alarm signal output by the missing pulse determination means 82 when a missing pulse is detected.

  As shown in FIG. 9, the pulse missing determining means 82 determines whether or not the diode output value is equal to or greater than a predetermined threshold value Th by using the falling edge of the clock pulse from the branching means 81 as a trigger signal. When the diode output value is smaller than the threshold value Th, a high level signal is output to the alarm generating means 83. The alarm generating unit 83 notifies the outside of the alarm indicating that a pulse missing has occurred when the signal from the pulse missing judging unit 82 changes from a low level to a high level. The alarm is notified by various methods such as image display and pronunciation. The occurrence of an alarm allows the operator to recognize that a pulse drop has occurred. If this alarm occurs frequently, it means that the performance of the laser generator has deteriorated or has reached the end of its life.

  The reference CCD image storage means 84 stores a reference CCD image 84a as shown in FIG. The reference CCD image 84a shows an image in a state where the laser beam is received at the center of the light receiving surface of the CCD camera 96 for optical axis inspection. The optical axis inspection CCD camera 96 outputs an inspection image 85a as shown in FIG. The optical axis deviation amount measuring means 85 captures the inspected image 85a from the optical axis inspection CCD camera 96, compares it with the reference CCD image 84a, measures the optical axis deviation amount, and calculates the deviation amount by the laser. Output to the controller 86. For example, when an image such as the inspected image 85a shown in FIG. 8 is output from the optical axis inspection CCD camera 96, the optical axis deviation measuring means 85 compares the X axis and the Y axis. The amount of direction deviation is measured and output to the laser controller 86. The laser controller 86 introduces the laser beam into a device related to the optical axis of the laser beam, that is, the emission condition of the laser generator 40 and the optical system member 50 so that the inspected image 85a and the reference CCD image 84a coincide. The arrangement and the like of the reflecting mirrors 33 to 35 are adjusted by feedback.

  The lens displacement amount measuring means 87 inputs a signal corresponding to the height of each of the condenser lenses 541 to 544 detected by the condenser lens height measuring system 26, and the height of each of the condenser lenses 541 to 544 is determined. It is determined whether it is within the allowable range or greatly deviated from this allowable range, and a control signal indicating how much the height of the condensing lenses 541 to 544 that are largely deviated should be adjusted is the lens height adjustment It outputs to the means 88. The lens height adjusting unit 88 adjusts the arrangement of the condenser lenses 541 to 544 in accordance with a control signal from the lens displacement amount measuring unit 87. When there is no height adjustment mechanism for the condensing lenses 541 to 544, the lens height adjusting unit 88 selects any of the condensing lenses 541 to 544 based on a control signal from the lens displacement amount measuring unit 87. The adjustment information may be transmitted to the operator (visual display, voice pronunciation, etc.).

  The irradiation laser state inspection unit 89 captures the image 89a from the CCD camera 28 for focus and optical axis adjustment, measures the shift amount of the focus and the optical axis based on this, and outputs the shift amount to the irradiation laser adjustment unit 8A. To do. For example, when an image 89a as shown in FIG. 8 is output from the CCD camera for focus and optical axis adjustment, the irradiation laser state inspection unit 89 uses the circular outline 89b (the condensing lens 541 in the image 89a). The line of the focus circle 89c (small circle in the image 89a) is detected on the basis of (a line corresponding to the outer edge of .about.544), and light is detected based on whether or not the focus circle 89c is located substantially at the center of the contour line 89b. The amount of deviation of the axis in the X-axis and Y-axis directions is measured and output to the irradiation laser adjusting means 8A. The irradiation laser state inspection unit 89 measures the size (area) of the focus circle 89c, and outputs the focus position based on the size (area) to the irradiation laser adjustment unit 8A. The irradiation laser adjusting unit 8A is configured to detect the half mirrors 511 to 513 and the reflection mirrors 521 to 528 in the optical system member 50 based on the signal corresponding to the optical axis shift amount and the focus position from the irradiation laser state inspection unit 89. Feed back and adjust the placement. The lens height adjusting unit 88 and the irradiation laser adjusting unit 8A may be omitted, and the laser controller 86 may have these functions.

  In the above-described embodiment, the case where the optical axis misalignment measuring unit 85 inspects the optical axis misalignment of the laser beam and the missing pulse determining unit 82 inspects the missing pulse during laser processing (scribe processing) has been described. As shown in FIG. 4, the pulse state of the laser beam may be inspected based on the output waveform from the high-speed photodiode 94. For example, in FIG. 10, the pulse width and pulse height of the laser beam may be measured, and an alarm may be generated when an abnormality occurs in these. The pulse width of the laser light is normal when the period during which the output waveform from the high-speed photodiode 94 is equal to or greater than a predetermined value is within a predetermined range, and when it is larger or smaller than this range, the pulse width is abnormal. And outputs an alarm. The pulse height of the laser beam is normal when the maximum value of the output waveform from the high-speed photodiode 94 is within the allowable range, and when it is larger or smaller than this allowable range, the pulse height is abnormal. Judge and output an alarm. As described above, since the laser light is always sampled, the quality of the laser light such as the pulse width and the pulse height (power) can be managed in real time. If the above-described pulse omission occurs frequently, it can be determined that the laser generator 40 is deteriorated or has a lifetime.

  FIG. 11 is a view of the optical system member of FIG. 1 as viewed from the lower side (substrate side). FIG. 11 shows a part of the optical system member 50 and the base plate 31. FIG. 11A is a diagram showing the positional relationship between the optical system member 50 and the base plate 31 shown in FIG. 1, and as shown in the figure, the end surface (upper end portion in the figure) of the optical system member 50 and the base The end surface (upper end portion in the figure) of the plate 31 coincides. FIG. 11B is a diagram showing a state in which the optical system member 50 is rotated about 30 degrees counterclockwise with respect to the base plate 31 with the center of the through hole 37 as the rotation axis. FIG. 11C is a diagram showing a state in which the optical system member 50 is rotated about 45 degrees counterclockwise with respect to the base plate 31 with the center of the through hole 37 as the rotation axis.

  In the solar panel manufacturing apparatus according to this embodiment, the optical system member 50 is configured to be freely rotatable with the center of the through hole 37, which is a laser light introduction hole, as the rotation axis. That is, the rotation of the optical system member 50 that is a branching unit is controlled with the traveling direction of the vertical laser light traveling from the reflection mirror 35 of FIG. 6 through the DOE 500 toward the half mirror 511 as the central axis. This makes it possible to variably control the angle θ between the laser beam branching direction and the relative movement direction of the laser beam with respect to the substrate (vertical direction in FIG. 11). In addition, although the existing techniques, such as a ball screw and a linear motor, are used as a rotational drive means of the optical system member 50, these illustration is abbreviate | omitted.

  As shown in FIG. 11, even when the angle between the laser beam branching direction and the laser beam scanning direction (vertical direction in FIG. 11) is variably controlled, the DOE 500 rotates relative to the relative movement direction of the laser beam. It is configured not to. That is, by using the DOE 500, the irradiation shape of the laser light shows an irradiation shape like a dotted square as shown in the condensing lenses 541 to 544 in FIG. Therefore, when the DOE 500 is rotated together with the rotation control of the optical system member 50, the dotted squares in the condenser lenses 541 to 544 also rotate according to the rotation amount. When the laser beam is scanned and irradiated in this state, square corners are positioned on both side ridge lines of the scribe line, and the ridge line shows a wavy shape. Therefore, as shown in FIGS. 11B and 11C, the DOE 500 is not rotated even if the rotation of the optical system member 50 is controlled as in this embodiment. The direction (vertical direction in FIG. 11) coincides with the left and right sides of the dotted square in the condenser lenses 541 to 544, and both sides of the scribe line can be formed very smoothly, and the optical system member 50 is rotated. Thus, even when the pitch of the scribe lines is appropriately controlled, it is possible to form a scribe line having a smooth ridge line. In the above-described embodiment, the case where only one DOE is provided in the optical path of the laser beam has been described. However, the DOE may be provided immediately before each condensing lens after branching. Even in this case, each DOE needs to be configured not to rotate even if the rotation of the optical system member 50 is controlled. The DOE 500 can be made independent of the rotation of the optical system member 50 by being directly connected to the base plate 31 in a form separated from the optical system member 50.

  FIG. 12 is a diagram illustrating the relationship between the rotation amount of the optical system member and the pitch width of the scribe line. 12A shows a state where the optical system member 50 is not rotated as shown in FIG. 11A, and FIG. 12B shows a state where the optical system member 50 is rotated about 30 degrees as shown in FIG. 11B. FIG. 12C shows the state of the scribe line when the laser scribing process is performed with the optical system member 50 rotated about 45 degrees as shown in FIG. 11C. If the pitch of the scribe lines in the case of FIG. 12A is P0, the pitch P30 in the case of FIG. 12B is P0 × cos 30 °, and the pitch P45 in the case of FIG. 12C is P0 × cos 45 °. Become. As described above, the solar panel manufacturing apparatus according to this embodiment can appropriately adjust the pitch width of the scribe line to a desired value by appropriately adjusting the rotation angle of the optical system member 50.

In the above-described embodiment, only the occurrence of missing pulses is observed, but by acquiring and storing the coordinate data (position data) of the location where the missing pulses have occurred, it is possible to perform scribe line repair processing. It becomes.
In the above-described embodiment, a part of the laser beam (sampling beam) branched and output by the beam sampler 93 is directly received using the CCD camera 96 for optical axis inspection, and the optical beam is processed by image processing. The case where the deviation is inspected has been described. An image showing a state where the laser beam is received at the center of the light receiving surface of the high-speed photodiode 94 is acquired as an inspection image by the CCD camera 96 for optical axis inspection or the split type photodiode. Thus, the optical axis deviation may be inspected.
In the above-described embodiment, the case of inspecting the optical axis deviation and the missing pulse of the laser beam has been described. However, the state of the laser beam is inspected by appropriately combining the optical axis deviation, the missing pulse, the pulse width, and the pulse height. You may make it do.
In the above-described embodiment, the case where the laser beam is irradiated from the surface of the substrate 1 on which the thin film is formed to form scribe lines (grooves) in the thin film is described. However, the laser beam is irradiated from the back surface of the substrate 1. A scribe line may be formed on the thin film on the substrate surface.
In the above-described embodiment, the solar panel manufacturing apparatus has been described as an example. However, the present invention can also be applied to an apparatus that performs laser processing, such as an EL panel manufacturing apparatus, an EL panel correction apparatus, and an FPD correction apparatus.

DESCRIPTION OF SYMBOLS 1 ... Board | substrate 10 ... Base 20 ... XY table 21, ... 23 ... Positioning pin 27a, 29a, 27b, 29b ... Image 26 ... Condensing lens height measuring system 28 ... CCD camera 30 for focus and optical axis adjustment ... Slide frame 31 ... Base plates 33 to 35 ... Reflecting mirror 37 ... Through hole 40 ... Laser generator 50 ... Optical system member 500 ... Phase type diffractive optical element (DOE)
511 to 513, half mirrors 521 to 528, reflection mirrors 531 to 534, shutter mechanisms 541 to 544, condensing lenses 52, 54, length measuring system 60 for autofocus, alignment camera devices 65 to 68, and substrate detection cameras 65a to 68a ... Image 70 ... Linear encoder 75 ... Database means 80 ... Control device 81 ... Branch means 82 ... Pulse drop determining means 83 ... Alarm generating means 84 ... Reference CCD image storage means 85 ... Optical axis deviation amount measuring means 86 ... Laser controller 87 ... Lens displacement measuring means 88 ... Lens height adjusting means 89 ... Irradiation laser state inspection means 8A ... Irradiation laser adjustment means 92, 93 ... Beam sampler 94 ... High-speed photodiode 96 ... CCD camera for optical axis inspection

Claims (9)

  When carrying a substrate into a processing position by a laser beam, an image near the four corners of the substrate is acquired, and bending (warping) of the substrate or chipping near the four corners of the substrate is detected based on the image. Substrate state inspection method.   2. The substrate state inspection method according to claim 1, wherein acquisition of images near the four corners of the substrate is performed using four image acquisition means provided corresponding to the four corners of the substrate. Inspection method.   When the substrate is carried into the processing position by the laser beam, an image of the outer peripheral edge of the substrate is acquired, and bending (warping) of the substrate and chipping of the outer peripheral edge of the substrate are detected based on the image. A substrate state inspection method.   4. The substrate state inspection method according to claim 3, wherein acquisition of an image of the outer peripheral edge of the substrate is performed using two image acquisition means provided corresponding to respective diagonals of the outer peripheral edge of the substrate. A substrate state inspection method. Carrying-in means for holding the substrate and carrying it into a processing position by laser light;
Holding means for holding the substrate carried in by the carry-in means;
Laser light irradiation means for applying a predetermined processing by irradiating the substrate held by the holding means with laser light;
Image acquisition means for acquiring images near the four corners of the substrate held by the carry-in means;
A laser processing apparatus comprising: detecting means for detecting bending (warping) of the substrate or chipping near the four corners of the substrate based on images near the four corners of the substrate acquired by the image acquisition means   6. The laser processing apparatus according to claim 5, wherein the image acquisition unit includes camera units that respectively acquire images near the four corners of the substrate. Carrying-in means for holding the substrate and carrying it into a processing position by laser light;
Holding means for holding the substrate carried in by the carry-in means;
Laser light irradiation means for applying a predetermined processing by irradiating the substrate held by the holding means with laser light;
Image acquisition means for acquiring an image of the outer periphery of the substrate held by the carry-in means;
A laser processing apparatus comprising: detecting means for detecting bending (warping) of the substrate and chipping of the outer peripheral edge of the substrate based on an image acquired by the image acquiring means.   8. The laser processing apparatus according to claim 7, wherein the image acquisition means is composed of two camera means provided corresponding to respective diagonals of the outer peripheral edge of the substrate. apparatus.   A solar panel manufactured by using the substrate state inspection method according to any one of claims 1 to 4 or the laser processing apparatus according to any one of claims 5 to 8. Production method.

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