JP2011161492A - Apparatus and method for inspecting laser beam-machined condition and apparatus and method for laser beam machining, and method of manufacturing solar panel - Google Patents

Abstract

A processing state by laser light can be detected during processing.
A part of laser light irradiation optical system 5 is shared in laser processing for performing predetermined processing on workpiece 1 by irradiating laser beam while moving relative to workpiece 1. An image of the laser processing location is acquired and the processing state is inspected based on the image. When the laser beam irradiation optical system 5 is configured to divide the laser beam into a plurality of beams and irradiate the workpiece 1 by a branching unit including the half mirrors 511 to 513 and the reflection mirrors 521 to 528, the laser beam branched into a plurality of beams. Laser light for illumination is provided on the work 1 via the condenser lens means so as to substantially coincide with the optical axes of the plurality of condenser lens means 541 to 544 provided to collect the light on the work 1 respectively. The processing state of the workpiece 1 is observed by acquiring images of the processing portions irradiated by the illumination laser beam with the imaging means 591 to 594.
[Selection] Figure 3

Description

  The present invention relates to a laser processing state inspection method and apparatus for inspecting a processing state when processing a thin film or the like using laser light, and more particularly to a laser processing method and apparatus, and a solar panel manufacturing method, and in particular, laser scribe performed at the time of solar panel creation. The present invention relates to a laser processing state inspection method and apparatus for inspecting a processing state during processing, a laser processing method and apparatus, and 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 manufacturing a solar panel module in this manner, scribe lines are formed on a thin film on a glass substrate with laser light at a pitch of about 10 mm, for example. The scribe line has a line width of about 30 μm, and is composed of three lines such that the distance between the lines is about 30 μm. 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. As a result, it was possible to form a scribe line having a stable depth and line width. As a method for manufacturing such a solar panel (photoelectric conversion device), the one described in Patent Document 1 is known.

JP 2006-054254 A JP 2008-066437 A

  In the solar panel manufacturing process, after the solar panel module is processed by processing with laser light, the generated solar panel module is inspected for power generation as described in Patent Document 2. That is, all processing is performed while the suitability / unsuitability of the processing by the laser beam is unknown, and the presence or absence of a defect such as a welding defect (reattachment) by the laser beam processing is detected in a subsequent process. Accordingly, since the defect detection time is delayed, the removal air flow rate cannot be controlled in real time, and the probability of occurrence of a defect due to the control delay tends to increase, which is a problem.

Therefore, the applicant of the present application proposes a laser processing state inspection method that can detect the state of laser beam processing early, feed back the conditions at the time of laser beam processing early, and reduce the defect occurrence rate. did. This is because the detection light irradiation laser, inspection CCD array sensor, and autofocus photodiode are provided on the upper surface of the workpiece, and the reflected light reflected from the surface of the workpiece among the light emitted from the detection light irradiation laser is reflected. Light is received by an autofocus photodiode, the height (focus) of the inspection CCD array sensor with respect to the work 1 is adjusted according to the amount of reflected light, and the surface of the work 1 in the light emitted from the detection light irradiation laser. The reflected light reflected from the light is received by the inspection CCD array sensor, and the reflected light detection signal corresponding to the reflected light quantity is analyzed by the control device.
On the other hand, since the laser beam is branched into four or eight by the optical system unit, it is necessary to detect the processing state by each laser beam after branching.

  The present invention has been made in view of the above points, and provides a laser processing state inspection method and apparatus, a laser processing method and apparatus, and a solar panel manufacturing method capable of detecting a processing state by laser light during processing. For the purpose.

The first feature of the laser processing state inspection method according to the present invention is that a laser beam irradiation optical system is used during laser processing in which predetermined processing is performed on a workpiece by irradiating the laser beam while moving it relative to the workpiece. It is to share the part, acquire an image of the laser processing portion, and inspect the processing state based on the image.
Processing with laser light is performed by irradiating the surface of the glass substrate with laser light emitted from a laser generator substantially perpendicularly to process a thin film on the glass substrate. In this invention, when the processing state of the laser beam is inspected at the time of processing, a part of the laser light irradiation optical system for processing is shared to inspect the processing state by the laser beam. As a result, it is possible to detect the processing state immediately after processing with laser light, and to feed back conditions and the like at the time of laser light processing based on that, thereby reducing the defect occurrence rate. .

A second feature of the laser processing state inspection method according to the present invention is the laser processing state inspection method according to the first feature, wherein the laser light irradiation optical system is formed by a branching unit including a half mirror and a reflection mirror. When configured to irradiate the workpiece with a plurality of laser beams branched, a plurality of condensing lens means provided to condense the laser beams branched into the plurality onto the workpiece, respectively. Irradiation laser light is irradiated onto the workpiece through the condenser lens means so as to substantially coincide with each optical axis, and an image of a processing portion irradiated with the illumination laser light is acquired by the imaging means. This is to observe the machining state of the workpiece.
When the laser beam is branched into four or eight by the optical system unit, a condensing lens is provided for each of the branched laser beams. In the present invention, this condensing lens means is shared, and a laser beam for illumination is irradiated onto the work through the condensing lens means so as to substantially coincide with the optical axis. Since the irradiated part is a processing part by a laser beam, an image of this processing part is acquired by an imaging means, and the processing state is observed. Thereby, the structure of the observation optical system can be simplified, and the processing state by the laser light can be easily detected.

The first feature of the laser processing state inspection apparatus according to the present invention is that a holding means for holding a workpiece, a laser beam irradiation unit for irradiating the workpiece with a laser beam, and a laser beam irradiation optical device constituting the laser beam irradiation unit. It is provided with inspection means for acquiring an image of the laser processing portion by sharing a part of the system and inspecting the processing state based on the image. This is an invention of a laser processing state inspection apparatus corresponding to the first feature of the laser processing state inspection method.

  A second feature of the laser processing state inspection apparatus according to the present invention is that the laser beam irradiation optical system is configured to divide the laser beam into a plurality of beams using a half mirror and a reflection mirror and irradiate the workpiece. Branching means and a plurality of condensing lens means for condensing the laser light branched into the plurality on the workpiece, respectively, and the inspection means substantially coincides with each optical axis of the condensing lens means As described above, the illumination laser light irradiation means for irradiating the workpiece with the illumination laser light via the condenser lens means, and the imaging means for acquiring the image of the processing spot irradiated by the illumination laser light irradiation means And a processing state inspection means for inspecting the processing state of the workpiece based on the image of the processing portion. This is an invention of a laser processing state inspection apparatus corresponding to the second feature of the laser processing state inspection method.

  A first feature of the laser processing method according to the present invention is a laser processing method for performing predetermined processing on a workpiece by irradiating the laser beam while moving the laser beam relative to the workpiece, and the laser processing method performs laser processing during the laser processing. A part of the light irradiation optical system is shared to acquire an image of the laser processing portion and inspect the processing state based on the image. This is an invention of a laser processing method using the first feature of the laser processing state inspection method.

  A second feature of the laser processing method according to the present invention is that the laser beam irradiation optical system is configured to divide the laser beam into a plurality of beams and irradiate the workpiece by a branching unit including a half mirror and a reflection mirror. The laser light for illumination is condensed so as to substantially coincide with the optical axes of a plurality of condensing lens means provided so as to condense the plurality of branched laser lights on the workpiece, respectively. The object is to observe the machining state of the workpiece by irradiating the workpiece through the lens means and acquiring an image of the machining portion irradiated by the illumination laser beam with the imaging means. This is an invention of a laser processing method using the second feature of the laser processing state inspection method.

  A first feature of the laser processing apparatus according to the present invention is that a holding unit that holds a workpiece, a laser beam irradiation unit that irradiates the workpiece with a laser beam, and a laser beam irradiation optical system that constitutes the laser beam irradiation unit. The image processing apparatus includes an inspection unit that acquires an image of the laser processing portion by sharing a part and inspects a processing state based on the image. This is an invention of a laser processing apparatus corresponding to the first feature of the laser processing method.

  A second feature of the laser processing apparatus according to the present invention is that the laser beam irradiation optical system is configured to divide the laser beam into a plurality of beams using a half mirror and a reflection mirror and irradiate the workpiece. Means and a plurality of condensing lens means for condensing the plurality of branched laser beams on the workpiece, respectively, and the inspection means substantially coincides with each optical axis of the condensing lens means Illumination laser light irradiation means for irradiating the workpiece with illumination laser light via the condenser lens means, imaging means for acquiring an image of a processing spot irradiated by the illumination laser light irradiation means, And a machining state inspection means for inspecting the machining state of the workpiece based on the image of the machining portion. This is an invention of a laser processing apparatus corresponding to the second feature of the laser processing method.

  The solar panel manufacturing method according to the present invention is characterized by the laser processing state inspection method according to the first or second feature, the laser processing state inspection device according to the first or second feature, the first or second feature. A solar panel is manufactured by using the laser processing method described in the second feature or the laser processing apparatus described in the first or second feature. In this method, a solar panel is manufactured by using any one of the laser processing state inspection method, the laser processing state inspection device, the laser processing method, or the laser processing device.

  According to the present invention, there is an effect that the characteristics of the laser beam can be measured at each processing position for each of the branched laser beams.

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 detailed structure of the process area part of FIG. 1 which performs the process of a scribe line. It is a figure which shows the detailed structure of the optical system member of FIG. It is a figure which shows the modification of the detailed structure of the optical system member of FIG. It is a schematic diagram which shows the structure of a 1st detection optical system member and a 2nd detection optical system member. It is a block diagram which shows the detail of a process of the control apparatus 80 of FIG. It is a figure which shows an example of operation | movement of the pulse missing determination means 82 of FIG. It is a figure which shows an example of the waveform output from the high-speed photodiode of FIG.

  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 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. The laser processing apparatus according to the present invention is configured so that alignment sections for performing alignment processing are provided at two positions on both sides of the laser processing station, and the alignment processing can be performed simultaneously during the laser processing to shorten the waiting time. is there.

  FIG. 1 is a diagram showing a schematic configuration of a solar panel (photoelectric conversion device) manufacturing apparatus using a laser processing apparatus according to an embodiment of the present invention, and shows an example of a return method. This manufacturing apparatus includes a carry-in / out robot station 141 and a laser processing station 10. The roller conveyor 121 sequentially conveys the glass substrates 1x to 1z between a film forming apparatus (not shown) and a manufacturing apparatus that performs laser scribing processing. The carry-in / out robot station 141 carries in and temporarily holds the glass substrate 1x formed by the previous film forming apparatus (not shown) conveyed on the roller conveyor 121 as a glass substrate 1m, and the glass substrate. A front / back reversing mechanism 143 that reverses the front and back of 1 m is provided so that the contents of laser processing (scribe line P1 processing, P2 processing or P3 processing) and the glass substrate 1m bend downward (warp). The glass substrate 1m is turned upside down and conveyed to the laser processing station 10. At this time, the loading / unloading robot station 141 transports the glass substrate 1m that has been turned upside down or not turned upside down to the laser processing station 10 as it is, and the glass substrate 1m that has been turned upside down or not turned upside down. The roller is conveyed to the right end position of 10 and then conveyed to the laser processing station 10. The carry-in / out robot station 141 directly receives the glass substrate processed by the laser processing station 10 by the front / back reversing mechanism unit 143 or receives the glass substrate 1r received at the right end position of the laser processing station 10 up to the front / back reversing mechanism unit 143. The glass substrate after the roller processing or air levitation conveyance and laser processing by the front / back reversing mechanism unit 143 is carried out to the roller conveyor 121 with the front / back reversed or the front / back reversed.

  The laser processing station 10 forms scribe lines on the thin film on the glass substrate carried in from the carry-in / out robot station 141, and includes alignment units 102 and 104, gripper units 106 to 109, gripper support driving units 110 and 111, A processing area 112 is provided. The alignment unit 102 receives the glass substrate 1m on the front / back reversing mechanism unit 143 of the carry-in / out robot station 141, aligns the received glass substrate 1n to a predetermined position, and performs a scribing process in the processing area unit 112. The glass substrate 1n is carried out to the front / back reversing mechanism unit 143 of the carry-in / out robot station 141. On the other hand, the alignment unit 104 receives a glass substrate 1r that is a glass substrate that has been turned upside down or not turned upside down by the front / back reversing mechanism unit 143 of the carry-in / out robot station 141 and that has been conveyed by roller or air floating up to the right end. The received glass substrate is aligned at a predetermined position, and the glass substrate 1 q that has been subjected to the scribing process in the processing area unit 112 is carried out to the right end position of the loading / unloading robot station 141.

  The gripper unit 106 holds one side (the lower side of the glass substrate 1o in FIG. 1) along the conveyance direction of the glass substrate 1o aligned by the alignment unit 102, and the gripper unit 107 holds the same glass substrate 1o. The other side of the side along the transport direction (the upper side of the glass substrate 1o in FIG. 1) is held. The gripper unit 108 holds one side (the lower side of the glass substrate 1q in FIG. 1) along the conveyance direction of the glass substrate 1q aligned by the alignment unit 104, and the gripper unit 107 has the same glass substrate 1q. The other side of the side along the conveyance direction (the upper side of the glass substrate 1q in FIG. 1) is held. The gripper support driving units 110 and 111 synchronize the glass substrates 1o and 1q held by the gripper units 106 and 107 or the gripper units 108 and 109 with the laser light of the processing area unit 112, and It is moved between the dotted glass substrate 1p. In synchronism with this movement, the processing area portion 112 irradiates the glass substrates 1o and 1q held by the gripper portions 106 and 107 or the gripper portions 108 and 109 and air-carrying and irradiating them with laser light to process predetermined scribe lines. I do. FIG. 1 shows a state in which predetermined scribe line processing is performed while moving the glass substrate 1o held by the grippers 106 and 107 in a state where the glass substrate 1o is floated to the position of the glass substrate 1q indicated by a dotted line.

  An example of the operation of the return type solar panel manufacturing apparatus of FIG. 1 will be described. First, the glass substrate 1x transported from the film forming apparatus of the previous stage via the roller conveyor 121 is temporarily held as a glass substrate 1m on the front / back reversing mechanism unit 143 by the carry-in / out robot station 141, where the front / back is reversed. Or reversed. The glass substrate 1m that has been turned upside down or not displayed is transferred to the alignment unit 102 of the laser processing station 10, where it is subjected to alignment processing. The alignment-treated glass substrate 1n is held by the gripper portions 106 and 107, and air-lifted to the processing area portion 112 as the glass substrates 1o and 1p, and processing of a predetermined scribe line is performed. On the other hand, at the time of alignment processing of the alignment unit 102 and processing of the processing area unit 112, the next glass substrate 1y conveyed through the roller conveyor 121 is transferred onto the front / back reversing mechanism unit 143 by the loading / unloading robot station 141. It is temporarily held as the substrate 1m, and is turned upside down or not turned upside down. The glass substrate 1m that has been turned upside down or not turned upside down is conveyed as a glass substrate 1r to a right end position corresponding to the alignment unit 104 of the laser processing station 10. The glass substrate 1r is transported to the alignment unit 104 of the laser processing station 10 where it is aligned. The glass substrate 1q that has been subjected to the alignment processing is held by the gripper portions 108 and 109, and waits until the processing of the glass substrate that is held by the gripper portions 106 and 107 and is air-lifted and conveyed is completed.

  When the laser processing for the glass substrates held by the grippers 106 and 107 is completed, the glass substrate 1o held by the grippers 106 and 107 is turned over from the position of the glass substrate 1n via the alignment unit 102. It is temporarily held as a glass substrate 1m on the section 143, and is transferred onto the roller conveyor 121 in order to be transferred to the next-stage film formation apparatus with the front and back reversed or without being reversed. On the other hand, when the glass substrate 1o held by the grippers 106 and 107 floats on the alignment unit 102 as the glass substrate 1n, the glass substrate 1q held by the grippers 108 and 109 becomes the glass substrate 1o, As 1p, the air is floated and moved to the processing area 112, and processing of a predetermined scribe line is performed. In the return-type solar panel manufacturing apparatus of FIG. 1, the waiting time and the like due to the alignment processing are greatly reduced by alternately repeating the above processing. Further, even if any one of the alignment units fails, the process can be continued by the other alignment unit.

  FIG. 2 is a diagram showing a detailed configuration of the processing area portion of FIG. 1 that performs the processing of the scribe line. The processing area portion is constituted by the laser processing station 10, the air floating stage 20, the gripper portions 106 and 107, the laser generator 40, the optical system member 50, the linear encoder 70, the control device 80, the detection optical system member, and the like.

  In FIG. 1, an air levitation stage 20 is provided in most of the laser processing station 10, but only a part thereof is shown in FIG. 2. On the upper side of the air levitation stage 20, the glass substrate 1 to be laser processed is held and controlled by the grippers 106 and 107 so as to be movable in the X-axis direction. A slide frame 30 that slides in the Y-axis direction while holding the optical system member 50 is provided on the laser processing station 10. The air levitation stage 20 is configured to be rotatable in the θ direction about the Z axis as a rotation axis. Note that when the amount of movement in the Y-axis direction can be sufficiently secured by the slide frame 30, the air levitation stage 20 may be configured to move only in the X-axis direction. In this case, the air levitation stage 20 may be configured as an X-axis table. In FIG. 2, the alignment units 102 and 104 are not shown.

  The slide frame 30 is attached to a moving table provided at four corners on the laser processing station 10. The slide frame 30 is controlled to move in the Y-axis 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 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 glass substrate 1 on the air levitation stage 20. Note that the number of divisions of the laser light is not limited to four, but may be two or more.

  The linear encoder 70 includes a scale member provided on the side surface of the X-axis moving table of the air levitation stage 20 and a detection unit attached to the gripper units 106 and 107. 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) of the gripper units 106 and 107 in the X-axis direction based on the detection signal from the linear encoder 70, and controls the output (laser frequency) of the laser generator 40.

  As illustrated, the optical system member 50 is provided on the side surface side of the base plate 31 and is configured to move in the Y-axis direction along the side surface of the base plate 31. The tip of the optical system member 50 is rotatable about the Z axis. A galvanometer 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 galvanometer mirror 33 uses two motors (rotary encoders) to scan the XZ two-dimensional area with laser light. The galvanometer mirror 33 is composed of a two-axis type (X, Z), and is composed of two motors and a mirror attached to the motor. The galvano control device 331 includes a driver and a power source for moving the motor, a microcomputer for controlling them, and the like.

  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 light emitted from the laser generator 40 is reflected toward the mirror 34 by the galvano mirror 33, and the laser light toward the mirror 34 is reflected toward the mirror 35 by the mirror 34. 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 beam emitted from the laser generator 40 may have any configuration as long as the laser beam is configured to be introduced into the optical system member 50 from the upper side through the through hole provided in the base plate 31. There 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.

  The beam sampler 332 is provided on the optical system member 50 between the galvanometer mirror 33 and the reflection mirror 34 so as to move along with the sliding movement of the optical system member 50. The beam sampler 332 is an element that samples a part of the laser beam (for example, about 10% of the laser beam or less) and branches and outputs it to the outside. The quadrant photodiode 333 is arranged so as to receive a part of the laser beam (sampling beam) branched by the beam sampler 332 in the vicinity of the center of the light receiving surface. Four types of output signals corresponding to the intensity of the laser light detected by the quadrant photodiode 333 are output to the galvano control device 331. The galvano control device 331 controls the two motors 33xy and 33yz of the galvano mirror 33 in real time according to the four types of output signals from the four-division photodiode 333. The motor 33xy controls the reflected laser beam of the galvanometer mirror 33 to rotate in a plane parallel to the upper surface (XY plane) of the base plate 31, and the motor 33zy controls the reflected laser beam of the galvanometer mirror 33 to the base plate 31. Is controlled in real time so as to rotate and move in a plane parallel to a plane (YZ plane) orthogonal to the upper surface of the.

  FIG. 3 is a diagram illustrating 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. FIG. 3 is a view of the inside of the optical system member 50 as viewed from the −X axis direction of FIG. 2. As shown in FIG. 3, 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 toward 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 branched 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 glass 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 glass 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 proceeds toward the reflection mirror 526 in the downward direction, and the transmission beam proceeds toward the reflection mirror 528 in the left direction. The beam reflected by the half mirror 513 is reflected by the reflecting mirrors 526 and 527 and is irradiated onto the glass 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 irradiated onto the glass 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 configured 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. As a result, even if the DOE 500 is disposed 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. In the embodiment of FIG. 3, the case where the optical path lengths are completely matched has been described. However, the optical path lengths can be slightly different as long as the top hat intensity distribution of the laser light can be maintained.

  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 glass substrate 1. The autofocus length measuring systems 52 and 54 are constituted by a detection light irradiation laser and an autofocus photodiode (not shown), and from the surface of the glass substrate 1 in the light irradiated from the detection light irradiation laser. The reflected 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 reflected light to adjust the height relative to the glass substrate 1 (the focus of the condensing lenses 541 to 544). To do. The focus adjustment drive mechanism is not shown.

  The optical system including the above-described half mirrors 511 to 513 and the reflection mirrors 521 to 528 transmits and reflects the processing laser beam having a wavelength of 1064 [nm] generated from the laser generator 40 to collect the condensing lens 541. To 544, that is, to each processing position. A processing state detection optical system for observing the processing state at each processing position is provided on the optical axis of each condensing lens 541 to 544 and above each reflecting mirror 521, 523, 527, 528. Yes. The processing state detection optical system includes illumination lasers 551 to 554, parallel light conversion lenses 561 to 564, optical components 571 to 574, condensing lenses 581 to 584, and monitor devices 591 to 594. The illumination lasers 551 to 554 generate inspection light for processing state observation with a wavelength of 685 [nm], and are applied to the optical components 571 to 574 from positions away from the optical axis of the condenser lenses 541 to 544. In contrast, laser light is emitted. The parallel light conversion lenses 561 to 564 convert the laser light emitted from the illumination lasers 551 to 554 into parallel rays and introduce the parallel light into the optical components 571 to 574. The optical components 571 to 574 are arranged on the extension of the optical axis of the condenser lenses 541 to 544, respectively, and the laser light emitted from the illumination lasers 551 to 554 is substantially matched with the optical axis of the processing laser light, And it reflects so that it may go to the condensing lenses 541-544. The optical components 571 to 574 have a transmittance of 50 percent and a reflectance of 50 percent for light with a wavelength of 685 [nm], and have a transmittance of 0 percent and a reflectance of 100 for light with a wavelength of 1064 [nm]. Percent (total reflection) part. On the other hand, the condensing lenses 581 to 584 condense the laser beams from the illumination lasers 551 to 554 reflected by the optical components 571 to 574 and irradiate the processed portions as illumination light. That is, the laser beams from the illumination lasers 551 to 554 reflected by the optical components 571 to 574 are respectively transmitted through the condenser lenses 581 to 584, the reflecting mirrors 521, 523, 527, and 528 and the condenser lenses 541 to 544. Irradiated to the processed part. Accordingly, the laser beams from the illumination lasers 551 to 554 reflected by the optical components 571 to 574 are condensed by the two lenses of the condenser lenses 541 to 544 and the condenser lenses 581 to 584. . The processing points irradiated by the laser beams from the illumination lasers 551 to 554 are imaged on the imaging surfaces of the monitor devices 591 to 594 by the condenser lenses 541 to 544 and the condenser lenses 581 to 584, and the imaging information thereof. Is output to the control device 80. The control device 80 detects the processing state of the workpiece 1 by the laser light generated by the laser generator 40 based on the imaging information from the monitor devices 591 to 594, analyzes problems such as processing defects and processing conditions, and performs laser processing. The machining state is controlled by feedback to the output conditions of the generator 40, the ambient temperature, and the like.

  FIG. 4 is a diagram illustrating a modification of the detailed configuration of the optical system member 50. 4, the same components as those in FIG. 3 are denoted by the same reference numerals, and the description thereof is omitted. The optical system member 50 in FIG. 3 is strictly configured so that the optical path lengths from the DOE 500 to the condenser lenses 541 to 544 are equal, but the range in which the top hat intensity distribution of the laser light can be maintained. Since the optical path lengths may be slightly different, the optical path lengths are slightly different for each optical axis in FIG. That is, in FIG. 4, the reflection mirrors 522, 523, 525, 526, and 527 for adjusting the optical path length, which are components of the optical system member 50 of FIG. 3, are omitted. The optical path length from the DOE 500 to the condenser lenses 542 and 543 is slightly shorter than the optical path length from the DOE 500 to the condenser lenses 541 and 544, but it is possible to maintain the top hat intensity distribution of the laser light. is there. Accordingly, there is an effect that the configuration of the optical system member 50 can be simplified.

  FIG. 5 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 condensing lens height measurement system 26 and a laser camera for inspecting the laser light state. 2 to 4, the condensing lens height measuring system 26 is shown as being provided at the end of the air levitation stage 20, but in practice, a gap formed in the air levitation stage 20. Projecting from the stage surface. The laser light state inspection CCD camera 28 receives laser light through the glass substrate 1 from a gap formed in the air levitation stage 20.

  When the height from the glass 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 FIGS. 3 and 4, the height of the lower surface of the optical system member 50 is the same. Even if it can be made, the height from the glass substrate 1 to each condensing lens 541-544 may not necessarily be the same. Therefore, in this embodiment, the condenser lens height measurement system 26 is attached to either one of the side surfaces in the X-axis direction of the air levitation stage 20 (the side surface in the −X-axis direction of the air levitation stage 20 in the figure) The height from the glass substrate 1 to each of the condensing lenses 541 to 544 of the optical system member 50a indicated by a dotted line is measured. 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 glass 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. If the height of the lower surface of the optical system member 50 is measured using the condensing lens height measuring system 26, the autofocus length measuring systems 52 and 54 can be omitted. .

  The laser light state inspection CCD camera 28 is provided so as to be located on the back side of the glass substrate 1 on the stage surface from the gap formed in the air floating stage 20. The laser light state inspection CCD camera 28 is installed so that the upper side of the air levitation stage 20 is visible. An image captured by the laser light state inspection CCD camera 28 is output to the control device 80. The control device 80 determines whether or not the spot diameter, shape, output, and the like of the laser light emitted from the condenser lenses 541 to 544 are appropriate. That is, the laser light state inspection 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 the laser light, the control device 80 For each of the branched laser beams, the characteristics of the laser beam at the processing location can be measured. Further, when each optical system related to the laser light 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 optical axis after the replacement are obtained. Adjustment and the like can be easily performed. Furthermore, by obtaining and digitizing the images of the laser beams output from the optical heads, it is possible to appropriately adjust the variations of the optical heads.

  As shown in FIG. 2, 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 galvanometer mirror 33. The beam samplers 92 and 93 are elements that sample a part of the laser beam (for example, about 0.4% or less of the laser beam) and branch out the output. 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 irradiated 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) of the gripper units 106 and 107 in the X-axis direction based on the detection signal from the linear encoder 70, controls the output (laser frequency) of the laser generator 40, and performs high speed operation. Based on the signals output from the photodiode 94 and the optical axis inspection CCD camera 96, the missing pulse of the laser light emitted from the laser generating device 40 is detected, or the laser generating device is determined based on the optical axis deviation amount of the laser light. The emission conditions of 40 are controlled, and the arrangement of the galvano mirror 33 and the reflection mirrors 34 and 35 for introducing the laser light in the optical system member 50 is feedback controlled.

  FIG. 6 is a block diagram showing details of processing of the control device 80 of FIG. 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, irradiation laser adjustment means 8A, processing state inspection means 8C and processing condition adjustment means 8E.

  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. 7 is a diagram showing an example of the operation of the pulse missing determining means 82 of FIG. 7A is an example of a detection signal (clock pulse) output from the branching unit 81, and FIG. 7B is an output signal (diode corresponding to the laser light intensity output from the high-speed photodiode 94. FIG. 7C 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. 7, 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. An inspection image 85a as shown in FIG. 6 is output from the CCD camera 96 for optical axis inspection. 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. 6 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 galvanometer mirror 33 and the reflection mirrors 34 and 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 means 89 captures the image 89a from the laser light state inspection CCD camera 28, measures the characteristics (spot diameter, shape, output, etc.) of the laser light based on the image 89a, and uses the measured value as the irradiation laser. Output to the adjusting means 8A. For example, when an image 89a as shown in FIG. 6 is output from the CCD camera for laser beam state inspection, the irradiation laser state inspection unit 89 has a circular outline 89b (the condensing lenses 541 to 541 in the image 89a). The position of the focus circle 89c (the small circle in the image 89a) is detected with reference to the outer edge of 544), and the optical axis is determined based on whether or not the focus circle 89c is located at the approximate center of the contour 89b. Is measured in the X-axis and Y-axis directions, and is output to the irradiation laser adjusting means 8A. The irradiation laser state inspection unit 89 measures the size (spot diameter / irradiation area) of the focus circle 89c and outputs the focus position based on the size to the irradiation laser adjustment unit 8A. Further, the irradiation laser state inspection unit 89 outputs a laser beam output based on the luminance level of the focus circle 89c to the irradiation laser adjustment unit 8A. The irradiation laser adjusting means 8A is based on the signals corresponding to the optical axis deviation, the focus position, and the light output from the irradiation laser state inspection means 89, and the half mirrors 511 to 513 and the reflection mirror 521 in the optical system member 50. The arrangement and the like of .about.528 are fed back and adjusted, and the emission conditions and the like of the laser generator 40 are controlled via the laser controller 86. The irradiation laser adjustment unit 8A may be omitted, and the laser controller 86 may have these functions.

  The machining state inspection means 8C takes in the imaging information from the monitor devices 591 to 594, and based on this, detects the machining state of the workpiece 1 by the laser beam, that is, whether or not a machining defect has occurred, and analyzes it. The result is output to the machining condition adjusting means 8E. Based on the analysis result from the processing state inspection unit 8C, the processing condition adjusting unit 8E feeds back the output conditions of the laser generator 40, which are laser processing conditions, the ambient temperature, and the like to the laser controller 86 so that the laser processing state is appropriately set. Control. The processing condition adjusting means 8E may be omitted and the laser controller 86 may have these functions.

  In the above-described embodiment, the optical axis misalignment measuring means 85 at the time of laser processing (scribing) detects the optical axis misalignment of the laser light, the pulse missing determining means 82 detects the pulse missing, and the machining state inspection means 8C indicates the machining state. Although the case of inspecting each has been described, the pulse state of the laser light may be inspected based on the output waveform from the high-speed photodiode 94 as shown in FIG. For example, in FIG. 8, the pulse width and the pulse height of the laser beam are measured, and if an abnormality occurs in these, an alarm may be generated, or the machining state detected by the machining state inspection means 8C An alarm may be generated based on the above. 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 missing pulses occur frequently or processing defects occur frequently, it can be determined that the laser generator 40 is deteriorated or has a life.

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 a scribe line repair process. 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 glass substrate 1 on which the thin film is formed and the scribe line (groove) is formed in the thin film is described. And you may make it form a scribe line in the thin film of 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 ... Glass substrate 1f, 1g, 1x-1z, 1m-1r ... Glass substrate 10 ... Laser processing station 10 ... Laser processing station 102, 104 ... Alignment part 106,107,108,109 ... Gripper part 110 ... Gripper support drive part DESCRIPTION OF SYMBOLS 112 ... Processing area part 121 ... Roller conveyor 141 ... Loading / unloading robot station 143 ... Front and back inversion mechanism part 20 ... Air floating stage 26 ... Length measuring system 28 ... CCD camera 30 for laser beam state inspection ... Slide frame 31 ... Base plate 33 ... Galvano mirror 331 ... Galvano control device 332 ... Beam sampler 333 ... Quadrant photodiode 33xy, 33yz ... Motor 34, 35 ... Reflection mirror 37 ... Through hole 40 ... Laser generators 41-44 ... Laser light 50, 50a ... Optical system members 500 ... Phase-type diffractive optics Child (DOE)
511 to 513... Half mirror 52. Autofocus length measuring systems 521 to 528. Reflecting mirrors 531 to 534. Shutter mechanisms 541 to 544... Condensing lens 551. Illumination lasers 561 to 564. ... optical components,
581-582 ... Condensing lens,
591 to 594... Monitor device,
DESCRIPTION OF SYMBOLS 70 ... Linear encoder 80 ... Control apparatus 81 ... Branch means 82 ... Pulse missing judgment means 83 ... Alarm generation means 84 ... Reference CCD image storage means 85 ... Optical axis deviation | shift amount measurement means 86 ... Laser controller 87 ... Lens displacement amount measurement means 88 ... Lens height adjustment means 89 ... Irradiation laser state inspection means 8A ... Irradiation laser adjustment means 8C ... Processing state inspection means 8E ... Processing condition adjustment means 92, 93 ... Beam sampler 94 ... High-speed photodiode 96 ... CCD camera for optical axis inspection

Claims (9)

  A part of the laser beam irradiation optical system is shared at the time of laser processing for performing predetermined processing on the workpiece by irradiating the workpiece while moving the laser beam relative to the workpiece, and an image of the laser processing portion is acquired. A laser processing state inspection method characterized by inspecting a processing state based on the image.   2. The laser processing state inspection method according to claim 1, wherein the laser beam irradiation optical system is configured to divide the laser beam into a plurality of beams and irradiate the workpiece by a branching unit including a half mirror and a reflection mirror. In this case, the laser beam for illumination is condensed so as to substantially coincide with the respective optical axes of a plurality of condensing lens means provided so as to condense the plurality of branched laser beams on the workpiece, respectively. A laser processing state characterized by observing a processing state of the workpiece by irradiating the workpiece through a lens unit and acquiring an image of a processing portion irradiated by the illumination laser beam with an imaging unit Inspection method. Holding means for holding the workpiece;
Laser light irradiation means for irradiating the workpiece with laser light;
Inspecting means for acquiring an image of the laser processing portion by sharing a part of a laser light irradiation optical system constituting the laser light irradiation means, and inspecting a processing state based on the image, Laser processing state inspection device. 4. The laser processing state inspection apparatus according to claim 3, wherein the laser beam irradiation optical system is configured to branch the laser beam into a plurality of beams using a half mirror and a reflection mirror and irradiate the workpiece. And a plurality of condensing lens means for condensing each of the plurality of branched laser beams on the workpiece,
The inspection means irradiates a laser beam for illumination onto the workpiece via the condenser lens means so as to substantially coincide with each optical axis of the condenser lens means; and The image processing apparatus includes an imaging unit that acquires an image of a processing portion irradiated by the laser beam irradiation unit for illumination, and a processing state inspection unit that inspects the processing state of the workpiece based on the image of the processing portion. Laser processing state inspection device. A laser processing method for performing predetermined processing on a workpiece by irradiating while moving the laser beam relative to the workpiece,
A laser processing method, wherein a part of a laser beam irradiation optical system is shared during the laser processing, an image of the laser processing portion is acquired, and a processing state is inspected based on the image.   The laser processing method according to claim 5, wherein the laser beam irradiation optical system is configured to divide the laser beam into a plurality of beams and irradiate the workpiece by a branching unit including a half mirror and a reflection mirror. The condensing lens means emits the laser light for illumination so as to substantially coincide with each optical axis of a plurality of condensing lens means provided so as to condense the laser light branched into a plurality on the workpiece. A laser processing method characterized by observing the processing state of the workpiece by irradiating the workpiece via a laser beam and acquiring an image of a processing portion irradiated by the illumination laser beam with an imaging means. Holding means for holding the workpiece;
Laser light irradiation means for irradiating the workpiece with laser light;
Inspecting means for acquiring an image of the laser processing portion by sharing a part of a laser light irradiation optical system constituting the laser light irradiation means, and inspecting a processing state based on the image, Laser processing equipment. In the laser processing apparatus of Claim 7,
The laser beam irradiation optical system includes a branching unit configured to divide the laser beam into a plurality of beams using a half mirror and a reflection mirror and irradiate the workpiece, and the laser beam branched into the plurality A plurality of condensing lens means for condensing on the workpiece,
The inspection means irradiates a laser beam for illumination onto the workpiece via the condenser lens means so as to substantially coincide with each optical axis of the condenser lens means; and The image processing apparatus includes an imaging unit that acquires an image of a processing portion irradiated by the laser beam irradiation unit for illumination, and a processing state inspection unit that inspects the processing state of the workpiece based on the image of the processing portion. Laser processing equipment.   The laser processing state inspection method according to claim 1 or 2, the laser processing state inspection device according to claim 3 or 4, the laser processing method according to claim 5 or 6, or the laser according to claim 7 or 8. A solar panel manufacturing method comprising manufacturing a solar panel using a processing apparatus.

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