JP5234648B2 - Laser processing method, laser processing apparatus, and solar panel manufacturing method - Google Patents

Description

  The present invention relates to a laser processing method, a laser processing apparatus, and a solar panel manufacturing method for processing a thin film or the like using laser light, and in particular, a laser processing method, a laser processing apparatus, and a solar capable of optimizing the power of laser light. The present invention relates to a 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. In such a processing method using laser light, a method described in Patent Document 1 is known for performing processing by branching a laser beam into a plurality of parts.

JP 2004-141929 A

In the laser processing method described in Patent Document 1, a laser is branched into a plurality of laser beams using a phase grating, and the workpiece is irradiated with the plurality of branched laser beams. In general, in a solar panel manufacturing process, a Gaussian beam is used as it is as a laser beam, the beam diameter is reduced to a specified width, the substrate is moved, and scribing is performed. When a Gaussian beam is used as the laser light, the processed shape becomes a mortar shape, and the film in the center part jumps too much, thereby causing a problem that the glass substrate is damaged. Also, in solar panels, there is a problem that the metal film rusts due to the sodium component precipitated from the glass substrate over time, accelerating the deterioration of the solar panel, so a general solar cell glass substrate is a glass substrate. A thin silicon dioxide (SiO ₂ ) film is coated between the transparent electrode layer.

  FIG. 1 is a diagram showing a processed state when a transparent electrode layer is scribed on a work in which a thin silicon dioxide film is coated between a glass substrate and a transparent electrode layer. As shown in FIG. 1A, a silicon dioxide film 1a is coated on a glass substrate 1, and a transparent electrode layer 1b is formed on the silicon dioxide film 1a. The glass substrate 1 is scribed using a Gaussian beam. FIG. 1B is a view of the scribe line formed by the scribing process as viewed from above, and FIG. 1C is a three-dimensional view of the scribe line as viewed from obliquely above. As shown in FIG. 1, when a Gaussian beam is used as the laser beam during scribing the transparent electrode layer, if the power of the laser beam is too strong, the processed shape becomes a mortar shape as shown in FIG. The film of (A part) jumps too much, the silicon dioxide film 1a is cut and scraped off, sodium of the glass substrate is deposited from the cut portion of the silicon dioxide film 1a, and the deterioration of the solar panel is accelerated by the secular change. There was a problem to do.

  An object of the present invention has been made in view of the above-described points, and provides a laser processing method, a laser processing apparatus, and a solar panel manufacturing method capable of performing scribing while optimizing the power of laser light. is there.

A first feature of the laser processing method according to the present invention is a laser processing method for applying a predetermined processing to a workpiece by irradiating the laser beam while moving the laser beam relative to the workpiece. The processing means of the workpiece is irradiated with an electron beam using an analyzing means, the generated characteristic X-ray is detected to measure the sodium component value, and the power of the laser beam is adjusted based on the sodium component value is there.
A silicon dioxide film is coated on a glass substrate which is a workpiece. When this silicon dioxide film is scraped off by laser processing, sodium precipitates from the glass substrate. In the present invention, an energy dispersive X-ray analysis means is used to irradiate a processing portion of a workpiece with an electron beam, and the generated characteristic X-ray is detected to measure the sodium component value. If this sodium component value is larger than the predetermined value, it means that the power of the laser beam is large. Therefore, the power of the laser beam is appropriately adjusted so that the sodium component value is not detected.

A second feature of the laser processing method according to the present invention is that in the laser processing method according to the first feature, the laser beam is branched into a plurality of laser beams, and the phase in the optical path before the laser beam is branched. The type diffractive optical element means is arranged to convert the laser light into a top hat intensity distribution, and the respective optical path lengths until the converted laser lights are irradiated onto the workpiece are the same. is there.
In this invention, when the laser beam is split into a plurality of laser beams and irradiated while moving the plurality of branched laser beams relative to the workpiece, the phase-type diffraction is performed in the optical path before the splitting of the laser beams. Optical element means (DOE: Diffractive Optical Element) is arranged to convert the laser light into a top hat intensity distribution. The converted laser beam is branched into a plurality of laser beams by a half mirror, a reflection mirror, or the like. At this time, the laser light is guided to the workpiece and irradiated so that the respective optical path lengths until the converted laser beams are irradiated onto the workpiece are equal to each other. As described above, the phase-type diffractive optical element is disposed in the optical path of the laser beam, the Gaussian intensity distribution of the laser beam is converted into a flat top (top hat) intensity distribution, and the workpiece is irradiated with the laser beam. The irradiating shape can be substantially square, both sides of the scribe line can be smoothly formed and the silicon dioxide film can be prevented from being scraped off. Further, even if a phase type diffractive optical element (DOE) is not provided for each of a plurality of branched laser beams, the substrate can be irradiated with a plurality of laser beams converted into a top hat beam, thereby reducing costs. . Furthermore, since the light is branched from one (DOE) light source, the characteristics of the branched laser light can be made relatively easy.

  A first feature of the laser processing apparatus according to the present invention is that the laser processing apparatus performs predetermined processing on the workpiece by irradiating the workpiece while moving the laser beam relative to the workpiece held by the holding means. An energy dispersive X-ray analyzer that irradiates an electron beam to a processing part of a work, detects a characteristic X-ray generated, and measures a sodium component value, and the sodium component measured by the energy dispersive X-ray analyzer And a control means for adjusting the power of the laser beam based on the value. 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 the laser processing apparatus according to the first feature, wherein the laser beam is branched into a plurality of laser beams, and the plurality of laser beams after branching are the workpiece. A branching means for irradiating the workpiece so that the respective optical path lengths until the laser beam is irradiated, and a phase provided in the optical path before branching of the laser beam, and converting the laser beam into a top hat intensity distribution Diffractive optical element means. 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 in that a solar panel is manufactured using the laser processing method according to the first or second feature or the laser processing apparatus according to the first or second feature. There is to do. In this method, a solar panel is manufactured using either the laser processing method or the laser processing apparatus.

  According to the present invention, there is an effect that scribing can be performed by optimizing the power of laser light.

It is a figure which shows the processing state at the time of performing the scribe process of a transparent electrode layer with respect to the workpiece | work with which the thin silicon dioxide film is coated between the glass substrate and the transparent electrode layer. 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 figure which shows an example of the analysis result of the process location at the time of using the laser beam of a gauss beam at the time of the scribe process of a transparent electrode layer. It is a block diagram which shows the detail of a process of a control apparatus. It is a figure which shows an example of operation | movement of the pulse missing determination means of FIG. It is a figure which shows an example of the waveform output from the high-speed photodiode of FIG. It is the figure which looked at the optical system member of FIG. 2 from the lower side (working 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. For the workpiece coated with a thin silicon dioxide film between the glass substrate and the transparent electrode layer, the processing state when the transparent electrode layer is scribed using the laser beam having the top hat intensity distribution described above. FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 2 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.

  2 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, an energy dispersive X-ray analyzer 90, and a 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 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. 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 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, half mirror 513, 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. 4 is a schematic diagram showing the configuration of the detection optical system member. As shown in FIGS. 2 and 4, the 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 means 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 means 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 means 80.

  The control device 80 detects the moving speed (moving frequency) of the XY table 20 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 is a high-speed photodiode. 94 and the signal output from the optical axis inspection CCD camera 96 are used to detect missing pulses of the laser light emitted from the laser generator 40, or based on the amount of optical axis deviation of the laser light. The emission conditions are controlled, and the arrangement of the reflection mirrors 33 to 35 for introducing the laser light in the optical system member 50 is feedback-controlled.

  The energy dispersive X-ray analyzer 90 is an energy dispersive X-ray analyzer that irradiates a sample with an electron beam, detects generated characteristic X-rays, and measures the elements constituting the sample and the amount thereof. . FIG. 5 is a diagram illustrating an example of an analysis result of a processing portion when a Gaussian laser beam is used at the time of scribing the transparent electrode layer. FIG. 5A is a diagram illustrating an analysis result of a substantially central portion (A portion in FIG. 1A) of a mortar-shaped processed shape. FIG. 5B is a view of a scribe line formed by scribe processing as viewed from above, and is the same as FIG. 1B. FIG. 5C is a diagram illustrating an analysis result of a portion where the silicon dioxide film 1a is present (B portion in FIG. 1A) in a mortar-shaped processed shape.

  As shown in FIG. 5, the analysis result of the portion A (the portion where the silicon dioxide film 1a was cut and scraped), that is, the base of the glass substrate, was 9.8% sodium, 3.4% magnesium, 1.3% aluminum. Silicon, 57.3%, calcium, 8.9%, and tin, 19.3%. On the other hand, the analysis results of part B (where the silicon dioxide film 1a is present) are: sodium 4.8%, magnesium 3.2%, aluminum 1.3%, silicon 55.4%, calcium 8.6%, titanium 2.0, tin 24.7%. When the analysis results of the A part and the B part are compared, the value of the sodium component without the silicon dioxide film 1a is greatly reduced to about one half of the value with the silicon dioxide film 1a. Therefore, in this embodiment, paying attention to the difference in the sodium component value, it is detected whether or not the silicon dioxide film 1a has been scraped off by scribing with laser light, and the power of the laser light is adjusted appropriately. .

  FIG. 6 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, irradiation laser adjustment means 8A, and silicon dioxide film presence / absence determination means 8C.

  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 illustrating an example of the operation of the missing pulse determination unit 82. 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 reflecting mirrors 33 to 35 are adjusted by feedback.

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

  The irradiation laser state inspection unit 89 captures the image 89a from the CCD camera 28 for focus and optical axis adjustment, measures the shift amount of the focus and the optical axis based on this, and outputs the shift amount to the irradiation laser adjustment unit 8A. To do. For example, when an image 89a as shown in FIG. 6 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.544), and light is detected based on whether or not the focus circle 89c is located substantially at the center of the contour line 89b. The amount of deviation of the axis in the X-axis and Y-axis directions is measured and output to the irradiation laser adjusting means 8A. The irradiation laser state inspection unit 89 measures the size (area) of the focus circle 89c, and outputs the focus position based on the size (area) to the irradiation laser adjustment unit 8A. The irradiation laser adjusting unit 8A is configured to detect the half mirrors 511 to 513 and the reflection mirrors 521 to 528 in the optical system member 50 based on the signal corresponding to the optical axis shift amount and the focus position from the irradiation laser state inspection unit 89. Feed back and adjust the placement. The lens height adjusting unit 88 and the irradiation laser adjusting unit 8A may be omitted, and the laser controller 86 may have these functions.

  The silicon dioxide film presence / absence determining means 8C receives the sodium component value (mass concentration value) output from the energy dispersive X-ray analyzer 90, and is greater than or equal to a predetermined threshold value Na (for example, 8.0%). A determination is made as to whether or not there is, and if the sodium component value is smaller than the threshold value Na, a high level signal is output to the laser controller 86. The laser controller 86 to which the high level signal is input adjusts the sodium component value to be smaller than the threshold value Na by reducing the emission condition (laser light power) of the laser generator 40. In this embodiment, the case where the laser controller 86 is controlled using the silicon dioxide film presence / absence determining means 8C has been described. However, the sodium component value (mass concentration value) output from the energy dispersive X-ray analyzer 90 is described. ) May be directly captured by the laser controller 86, and the power of the laser beam may be feedback controlled based on the sodium component value.

  In the above-described embodiment, the case where the optical axis misalignment measuring unit 85 inspects the optical axis misalignment of the laser beam and the missing pulse determining unit 82 inspects the missing pulse during laser processing (scribe processing) has been described. As shown in FIG. 4, the pulse state of the laser beam may be inspected based on the output waveform from the high-speed photodiode 94. For example, in FIG. 8, the pulse width and pulse height of the laser beam may be measured, and an alarm may be generated when an abnormality occurs in these. The pulse width of the laser light is normal when the period during which the output waveform from the high-speed photodiode 94 is equal to or greater than a predetermined value is within a predetermined range, and when it is larger or smaller than this range, the pulse width is abnormal. And outputs an alarm. The pulse height of the laser beam is normal when the maximum value of the output waveform from the high-speed photodiode 94 is within the allowable range, and when it is larger or smaller than this allowable range, the pulse height is abnormal. Judge and output an alarm. As described above, since the laser light is always sampled, the quality of the laser light such as the pulse width and the pulse height (power) can be managed in real time. If the above-described pulse omission occurs frequently, it can be determined that the laser generator 40 is deteriorated or has a lifetime.

  FIG. 9 is a view of the optical system member of FIG. 1 as viewed from the lower side (substrate side). FIG. 9 shows a part of the optical system member 50 and the base plate 31. FIG. 9A 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. 9B is a view 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. 9C 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. 6 through the DOE 500 toward the half mirror 511 as the central axis. Accordingly, the angle θ formed by the laser beam branching direction and the relative movement direction of the laser beam with respect to the substrate (vertical direction in FIG. 9) can be variably controlled. 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. 9, even when the angle formed between the laser beam branching direction and the laser beam scanning direction (vertical direction in FIG. 9) is variably controlled, the DOE 500 rotates with respect to the relative movement direction of the laser beam. It is configured not to. That is, by using the DOE 500, the irradiation shape of the laser light shows an irradiation shape like a dotted square as shown in the condensing lenses 541 to 544 in FIG. Therefore, when the DOE 500 is rotated together with the rotation control of the optical system member 50, the dotted squares in the condenser lenses 541 to 544 also rotate according to the rotation amount. When the laser beam is scanned and irradiated in this state, square corners are positioned on both side ridge lines of the scribe line, and the ridge line shows a wavy shape. Therefore, as shown in FIGS. 9B and 9C, 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. 9) 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. 10 is a diagram illustrating the relationship between the rotation amount of the optical system member and the pitch width of the scribe line. 10A shows a state where the optical system member 50 is not rotating as shown in FIG. 9A, and FIG. 10B shows a state where the optical system member 50 is rotated about 30 degrees as shown in FIG. 9B. FIG. 10C 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. 9C. When the pitch of the scribe line in the case of FIG. 10A is P0, the pitch P30 in the case of FIG. 10B is P0 × cos 30 °, and the pitch P45 in the case of FIG. 10C 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. FIG. 11 shows a case where the transparent electrode layer is scribed using a laser beam having the above-mentioned top hat intensity distribution on a work in which a thin silicon dioxide film is coated between the glass substrate and the transparent electrode layer. It is a figure which shows the processing state of. As shown in FIG. 11, a silicon dioxide film 1a is coated on a glass substrate 1, and a transparent electrode layer 1b is formed on the silicon dioxide film 1a. The glass substrate 1 is scribed using a laser beam having a top hat intensity distribution as shown in FIGS. As shown in FIG. 11, when laser light having a top hat intensity distribution is used as the laser light during scribing of the transparent electrode layer, the power of the laser light becomes uniform in the irradiated region. The shape becomes flat, and only the transparent electrode layer 1b can be scraped off from the silicon dioxide film 1a. Even if the sodium component value in the scribe line having the processed shape as shown in FIG. 11 is detected using the energy dispersive X-ray analyzer 90, the sodium component value is sufficiently smaller than the threshold value Na, There is no risk of sodium precipitation on the glass substrate.

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 embodiment, the case of inspecting the optical axis deviation and the missing pulse of the laser beam has been described. However, the laser beam state is inspected by appropriately combining the optical axis deviation, the missing pulse, the pulse width, and the pulse height. You may make it do.
In the above-described embodiment, the case where the laser beam is irradiated from the surface of the substrate 1 on which the thin film is formed and the scribe line (groove) is formed in the thin film is described. A scribe line may be formed on the thin film on the substrate surface.
In the above-described embodiment, the solar panel manufacturing apparatus has been described as an example. However, the present invention can also be applied to an apparatus that performs laser processing, such as an EL panel manufacturing apparatus, an EL panel correction apparatus, and an FPD correction apparatus.

DESCRIPTION OF SYMBOLS 1 ... Work 1a ... Silicon dioxide film 1b ... Transparent electrode layer 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 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 8C ... Silicon dioxide film presence / absence judgment means 90 ... Energy dispersive X-ray analyzer 92 , 93 ... Beam sampler 94 ... High-speed photodiode 96 ... CCD camera for optical axis inspection

Claims (5)

A laser processing method for performing predetermined processing on a workpiece by irradiating while moving the laser beam relative to the workpiece,
The processing part of the workpiece is irradiated with an electron beam using an energy dispersive X-ray analysis means, the characteristic X-ray generated is detected to measure the sodium component value, and the power of the laser beam based on the sodium component value The laser processing method characterized by adjusting.   2. The laser processing method according to claim 1, wherein the laser beam is branched into a plurality of laser beams, phase type diffractive optical element means is disposed in an optical path before the laser beam is branched, and the laser beam is split into a top hat intensity. A laser processing method, wherein the optical path lengths are converted to distributions and the lengths of the converted laser beams until the workpieces are irradiated with the plurality of converted laser beams are the same. In a laser processing apparatus that performs predetermined processing on a workpiece by irradiating the workpiece while moving the laser beam relative to the workpiece held by the holding means,
An energy dispersive X-ray analysis means for irradiating a processing portion of the workpiece with an electron beam, detecting a generated characteristic X-ray and measuring a sodium component value;
And a control means for adjusting the power of the laser beam based on the sodium component value measured by the energy dispersive X-ray analysis means. The laser processing apparatus according to claim 3, wherein the laser light is branched into a plurality of laser lights, and the respective optical path lengths until the branched laser lights are irradiated onto the workpiece are the same. A laser processing apparatus comprising: a branching unit that irradiates the workpiece; and a phase type diffractive optical element unit that is provided in an optical path before branching of the laser beam and converts the laser beam into a top hat intensity distribution. .   A solar panel manufacturing method, wherein a solar panel is manufactured using the laser processing method according to claim 1 or 2, or the laser processing apparatus according to claim 3 or 4.

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