JP5371514B2 - Laser light state inspection method and apparatus, and solar panel manufacturing method - Google Patents

Description

  The present invention relates to a laser light state inspection method and apparatus for inspecting the state of laser light when processing a thin film or the like using laser light, and a solar panel manufacturing method, and more particularly to the optical axis of the laser light at the time of solar panel creation. The present invention relates to a laser light state inspection method and apparatus for inspecting a state and an output state of laser light, 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. Thus, when manufacturing a solar panel module, the scribe line is formed in the thin film on a glass substrate with a laser beam with a pitch of 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

  Conventionally, laser light focusing and optical axis adjustment are performed by actually irradiating a substrate with laser light and visually observing the processing state (scribe line) with an optical microscope to finely adjust the optical system. Therefore, there is a problem that adjustment takes too much time.

  The present invention has been made in view of the above points, and provides a laser light state inspection method and apparatus and a solar panel manufacturing method capable of inspecting the state of the optical axis of laser light and the output state of laser light. That is.

A first feature of the laser beam state inspection method according to the present invention is a laser beam state inspection method for performing predetermined processing on a workpiece by irradiating the laser beam while moving the laser beam relative to the workpiece. The object is to receive a laser beam directed toward the processing surface of the workpiece using a light receiving unit that moves together with the workpiece, and to inspect the state of the laser beam based on a signal from the light receiving unit.
The laser beam emitted from the laser generator is finally irradiated substantially perpendicularly to the work surface of the workpiece. In this invention, the light receiving means that moves together with the work is provided on the side surface of the work holding means, for example, and the laser light applied to the work is received using the light receiving means, and the optical axis of the laser light is based on the received light signal. In this configuration, the shift state and the focus state can be inspected. That is, at the time of the laser beam state inspection, the output intensity of the laser beam is made relatively weak, and the same laser beam as that irradiated on the workpiece is used using a light receiving means such as a CCD camera provided at substantially the same position as the workpiece. By directly receiving light, the position and focus (diameter and shape) of the optical axis are grasped as an image, and based on this, the optical axis shift and the focus position can be inspected.

  A second feature of the laser beam state inspection method according to the present invention is that, in the laser beam state inspection method according to the first feature, the light receiving unit is provided in a holding unit that holds and moves the workpiece. It is in. In this case, the light receiving means is provided in the work holding means so as to receive the laser light actually irradiated onto the work surface of the work.

  A third feature of the laser light state inspection method according to the present invention is the laser light state inspection method according to the first or second feature, wherein the optical axis shift of the laser light is based on a signal from the light receiving means. It is to inspect at least one of the state and the focus state. The light receiving means is composed of a CCD camera, and by directly receiving the laser light, the position of the optical axis and the size (diameter and shape) of the focus are grasped as an image, and the optical axis deviation state and the focus state of the laser light are determined. Can be easily inspected.

  According to a fourth aspect of the laser light state inspection method of the present invention, in the laser light state inspection method according to the first, second, or third feature, the laser light is branched from a half mirror and a reflection mirror. The means is branched into a plurality of laser beams, and the workpiece is irradiated with the plurality of branched laser beams. In this method, a laser beam is split into a plurality of beams by using a branching unit including a half mirror and a reflection mirror, and the workpiece is irradiated with the laser beam.

  A fifth feature of the laser beam state inspection method according to the present invention is the laser beam state inspection method according to the fourth feature, wherein a plurality of condensing lenses corresponding to each laser beam branched by the branching unit. The height measuring means for measuring the height is provided in the holding means for holding and moving the workpiece. In this configuration, a length measuring system for measuring the height of the condenser lens provided for each of the laser beams branched into a plurality by the branching means is provided in the work holding means in the same manner as the light receiving means.

  A first feature of the laser beam state inspection 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 to perform a predetermined machining process, and a machining surface of the workpiece. A light receiving means for receiving the laser beam directed to, and an inspection means for inspecting the state of the laser light based on a signal from the light receiving means. This is an invention of a laser beam state inspection apparatus corresponding to the first feature of the laser beam state inspection method.

  According to a second aspect of the laser beam state inspection apparatus of the present invention, in the laser beam state inspection apparatus according to the first feature, the light receiving unit is provided in a holding unit that holds and moves the workpiece. It is in. This is an invention of a laser beam state inspection apparatus corresponding to the second feature of the laser beam state inspection method.

  According to a third aspect of the laser light state inspection apparatus of the present invention, in the laser light state inspection apparatus according to the first or second feature, the inspection unit is configured to transmit the laser based on a signal from the light receiving unit. It is to inspect at least one of the optical axis deviation state and the focus state of light. This is an invention of a laser beam state inspection apparatus corresponding to the third feature of the laser beam state inspection method.

  According to a fourth aspect of the laser light state inspection apparatus of the present invention, in the laser light state inspection apparatus according to the first, second, or third feature, the laser light is branched by a half mirror and a reflection mirror. Branching means for branching into a plurality of laser beams and irradiating the workpiece with the branched laser beams. This is an invention of a laser beam state inspection apparatus corresponding to the fourth feature of the laser beam state inspection method.

  According to a fifth aspect of the laser light state inspection apparatus of the present invention, in the laser light state inspection apparatus according to the fourth aspect, a plurality of condensing lenses corresponding to each laser light branched by the branching unit. The height measuring means for measuring the height is provided in the holding means for holding and moving the workpiece. This is an invention of a laser beam state inspection apparatus corresponding to the fifth feature of the laser beam state inspection method.

  A feature of the solar panel manufacturing method according to the present invention is any one of the laser light state inspection method according to any one of the first feature to the fifth feature or the first feature to the fifth feature. A solar panel is manufactured by using the laser beam state inspection apparatus according to 1. In this method, a solar panel is manufactured using any one of the laser beam state inspection method and the laser beam state inspection apparatus.

  According to the present invention, there is an effect that the state of the optical axis of the laser beam and the output state of the laser beam can be inspected before processing.

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 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 Drawing 1 from the lower side (work 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 laser beam 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, a linear encoder 70, a control device 80, a first detection optical system member, and a second detection. It is comprised by the 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 workpiece 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 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 work 1 on the XY table 20. Note that the number of divisions of the laser light is not limited to four, but may be two or more.

  The alignment camera device 60 acquires images near the both end portions (front and rear edge portions in the X-axis direction) of the work 1 on the XY table 20. 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 workpiece 1 and uses it for the subsequent alignment processing of the workpiece 1. 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 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 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 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.

  FIG. 2 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. FIG. 2 is a view of the inside of the optical system member 50 as viewed from the −X axis direction of FIG. 1. As shown in FIG. 2, 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 reflecting mirror 521, and is irradiated onto the work 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 workpiece 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 reflection mirrors 526 and 527 and is irradiated onto the work 1 through the condensing lens 543 in the downward direction. The beam that has passed through the half mirror 513 is reflected by the reflecting mirror 528, and is irradiated onto the work 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. 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.

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

  FIG. 3 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 25 and a focus and optical axis adjustment CCD camera 27. In FIG. 3, the condensing lens height measuring system 25 and the focus and optical axis adjusting CCD camera 27 are shown in an overlapping manner, so that they are distinguished by reference numerals. When the height from the workpiece 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. 2, the height of the lower surface of the optical system member 50 is the same. Even if it can, the height from the workpiece | work 1 to each condensing lens 541-544 cannot necessarily be made the same. Therefore, in this embodiment, the condenser lens height measuring system 25 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 drawing). 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 25 is output to the control device 80. The control device 80 determines whether or not the height from the workpiece 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 25. 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 27 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. It is provided at 25 adjacent positions (neighborhoods). The focus and optical axis adjusting CCD camera 27 associates the positions of the XY table 20 and the condenser 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 27 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 27 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. In addition, when replacing each optical system related to laser light, such as the laser generator 40 and the optical system member 50, before and after replacement, images are acquired and digitized to adjust the focus and optical axis after replacement. Can be easily performed. Furthermore, in the case of a plurality of heads, the variation in assembly of each head can be adjusted appropriately by acquiring and digitizing each laser beam image.

  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 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) 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 25, the CCD camera 27 for focus and optical axis adjustment, the high-speed photodiode 94, and the CCD camera 96 for optical axis inspection, from the work 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, In order to detect missing pulses, control the emission conditions of the laser generator 40 based on the amount of optical axis deviation of the laser light, and introduce the laser light into the optical system member 50 Or feedback control of the arrangement of the reflecting mirrors 33 to 35, or to adjust the arrangement of the condenser lens 541 to 544.

  FIG. 4 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. 5 is a diagram showing an example of the operation of the missing pulse determination means 82. 5A is an example of a detection signal (clock pulse) output from the branching means 81, and FIG. 5B is an output signal (diode corresponding to the laser light intensity output from the high-speed photodiode 94. FIG. 5C 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. 5, the pulse missing determining means 82 determines whether or not the diode output value is equal to or greater than a predetermined threshold Th 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. 4 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 25, 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 27 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. 4 is output from the focus and optical axis adjusting CCD camera, 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. 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 (scribing) 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. 6, 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 light 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. 7 is a view of the optical system member of FIG. 1 viewed from the lower side (workpiece side). FIG. 7 shows a part of the optical system member 50 and the base plate 31. FIG. 7A 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 drawing, the end surface (upper end portion in the figure) of the optical system member 50 and the base are shown. The end surface (upper end portion in the figure) of the plate 31 coincides. FIG. 7B 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. 7C is a view 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. 2 through the DOE 500 toward the half mirror 511 as the central axis. This makes it possible to variably control the angle θ formed by the laser beam branching direction and the relative movement direction of the laser beam with respect to the workpiece (vertical direction in FIG. 7). 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. 7, even when the angle between the laser beam branching direction and the laser beam scanning direction (vertical direction in FIG. 7) 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 such as 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. 7B and 7C, scanning is performed as shown in FIGS. 7B and 7C by adopting a configuration in which 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. 7) 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. 8 is a diagram showing the relationship between the rotation amount of the optical system member and the pitch width of the scribe line. 8A shows a state where the optical system member 50 is not rotated as shown in FIG. 7A, and FIG. 8B shows a state where the optical system member 50 is rotated about 30 degrees as shown in FIG. 7B. FIG. 8C 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. 7C. If the pitch of the scribe lines in FIG. 8A is P0, the pitch P30 in FIG. 8B is P0 × cos 30 °, and the pitch P45 in FIG. 8C 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 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 workpiece 1 on which the thin film is formed to form the scribe line (groove) on the thin film is described. However, the laser beam is irradiated from the back surface of the workpiece 1. A scribe line may be formed on the thin film on the workpiece 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 ... Work 10 ... Base 20 ... XY table 30 ... Slide frame 31 ... Base plate 33-35 ... Reflection 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 and 54 ... length measurement system 60 for autofocus ... alignment camera device 70 ... linear encoder 80 ... control device 81 ... Branch means 82 ... Pulse missing judgment means 83 ... Alarm generation means 84 ... Reference CCD image storage means 85 ... Optical axis deviation 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 92, 93 ... Beam sampler 94 ... High speed photodiode 96 ... Optical axis inspection CCD camera

Claims (6)

A laser beam state inspection method for performing predetermined processing on a workpiece by irradiating while moving the laser beam relative to the workpiece,
A laser beam traveling toward the machining surface of the workpiece is received using a light receiving unit that moves with the workpiece, and the state of the laser beam is inspected based on a signal from the light receiving unit, and the laser beam is reflected by a half mirror and a reflection. Branching into a plurality of laser beams by a branching means comprising a mirror, irradiating the workpiece with a plurality of branched laser beams,
Measuring the height of each of a plurality of condensing lenses corresponding to each laser beam branched by the branching unit using a height measuring unit provided in a holding unit that holds and moves the workpiece. A laser beam state inspection method characterized by the above.   2. The laser beam state inspection method according to claim 1, wherein the light receiving unit is provided in a holding unit that holds and moves the workpiece.   3. The laser beam state inspection method according to claim 1, wherein at least one of an optical axis deviation state and a focus state of the laser beam is inspected based on a signal from the light receiving means. Inspection method. Holding means for holding the workpiece;
Laser light irradiation means for irradiating the workpiece with laser light to perform a predetermined processing;
A light receiving means for receiving a laser beam directed to the processing surface of the workpiece;
Inspection means for inspecting the state of the laser beam based on a signal from the light receiving means ;
Branching irradiation means for branching the laser light into a plurality of laser lights by a branching means comprising a half mirror and a reflection mirror, and for irradiating the workpiece with the plurality of branched laser lights;
A height measuring unit that is provided in a holding unit that holds and moves the workpiece and measures the heights of a plurality of condensing lenses corresponding to the laser beams branched by the branching unit; A laser light state inspection apparatus characterized by the above. 5. The laser beam state inspection apparatus according to claim 4 , wherein the light receiving unit is provided in a holding unit that holds and moves the workpiece. In the laser light condition inspection apparatus according to claim 4 or 5, wherein the test means, characterized by inspecting at least one of optical axis shift state and the focus state of the laser light based on a signal from said light receiving means A laser beam state inspection device.

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