JP2012000640A - Laser processing device and laser processing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve processing quality while preventing the edge deletion processing time of a thin-film photovoltaic cell panel from increasing.SOLUTION: A process is repeated in which a light spot is made to scan a thin-film photovoltaic cell panel 102 in a main-scanning direction toward which an optical unit proceeds, is then moved to the next row, is then made to scan in the opposite direction to the main-scanning direction, and is then moved to the next row in the order of arrows 311a, 311b to 311k. After the light spot is made to scan in the direction of the arrow 311k, the light spot is made to scan in the direction of an arrow 311l and is made to scan in the same manner also in the next processing block. This scanning is repeated until peeling of the thin film in a linear region along a side 301a of the thin-film photovoltaic cell panel 102 is completed. For example, a laser processing device for performing an edge deletion can apply.

Description

  The present invention relates to a laser processing apparatus and a laser processing method, and more particularly, to a laser processing apparatus and a laser processing method suitable for use in peeling a thin film from a substrate using laser light.

  For example, a thin film solar cell panel is formed on a glass substrate of 1.1 m × 1.4 m, and after electrode processing, film protection of the film surface, etc., the periphery of the panel is held with an aluminum frame. It will be completed. Therefore, when the thin-film solar battery panel is used for a long time, there is a possibility that the protective film is penetrated and the aluminum frame and the film surface are short-circuited. Therefore, edge deletion is performed to peel the thin film around the edge portion of the thin film solar cell panel in order to enhance the electrical insulation.

  Conventional edge deletion has been performed using sandblasting or a grindstone. However, in these methods, the surface after processing becomes rough, the adhesion of the protective film is lowered, and problems such as rainwater entering between the protective film and the panel may occur. Therefore, in recent years, edge deletion processing using a laser that can peel only the film surface without scraping off the glass substrate has attracted attention.

  FIG. 1 shows an example of a laser beam scanning method when edge deletion of a thin-film solar battery panel is performed by laser processing. This scanning method is disclosed in, for example, Patent Document 1. In this scanning method, the laser beam is scanned in the main scanning direction (x-axis direction) as a whole while scanning the laser beam zigzag in the sub-scanning direction (y-axis direction) within the range 21, thereby thin film solar cell panel The thin film in the region 11B indicated by the oblique lines around the 11 sides 11A is removed.

  FIG. 2 shows an example of a position (hereinafter referred to as a light spot) where the thin film solar cell panel 11 is irradiated with the laser light when the laser light is scanned as shown in FIG. In FIG. 2, each light spot is indicated by a rectangular frame. As shown in this figure, the area where adjacent light spots overlap is increased, resulting in a longer processing time.

  Therefore, as shown in FIG. 3, it is conceivable to reduce the overlap of the light spots by scanning the light spots in a lattice pattern. In this case, the light spot is first scanned by one column in the direction of the arrow 51a (sub-scanning direction), advanced by one column in the direction of the arrow 51b (main scanning direction), and the direction of the arrow 51c in the next column, that is, 1 Scanning is performed in such a manner that scanning is performed in the direction opposite to that of the column and the column is advanced by one column in the direction of the arrow 51d (main scanning direction).

  Here, with reference to FIG. 4, the case where a light spot is scanned as shown in FIG. 3 using two galvanometer scanners that scan laser light in the x-axis direction and the y-axis direction will be described. Note that arrows 61a to 61d in FIG. 4 indicate directions in which laser light is scanned by the galvanometer scanner. Further, hereinafter, the position of the thin film solar cell panel 11 is fixed, and an optical system head (not shown) that emits laser light to the thin film solar cell panel 11 is set in the direction of the arrow 52 in FIG. In this direction, it is conveyed at a constant speed.

  First, in order to scan the light spot in the direction of the arrow 51a in FIG. 3, the laser light is scanned in the direction of the arrow 61a (the negative direction of the x axis and the positive direction of the y axis). In other words, in order to scan the light spot in the y-axis direction, the laser beam is scanned obliquely backward with respect to the conveyance direction of the optical system head. Note that the scanning distance Ly in the y-axis direction of the laser light at this time substantially matches the width in the y-axis direction of the range 21 in FIG. 3, and the scanning distance Lx in the x-axis direction scans the light spot for one column. In the meantime, the distance substantially coincides with the distance the optical system head moves in the x-axis direction.

  Next, in order to scan the light spot in the direction of the arrow 51b in FIG. 3, the laser light is scanned in the direction of the arrow 61b (the positive direction of the x axis). At this time, the scanning distance of the laser beam in the x-axis direction substantially coincides with the distance Lx.

  Next, in order to scan the light spot in the direction of the arrow 51c in FIG. 3, the laser light is scanned in the direction of the arrow 61c (the negative direction of the x axis and the negative direction of the y axis). That is, compared with the scanning direction of the arrow 61a, the scanning direction in the x-axis direction is the same, and the scanning direction in the y-axis direction is reversed.

  Next, in order to scan the light spot in the direction of the arrow 51d in FIG. 3, the laser light is scanned in the direction of the arrow 61d (the positive direction of the x axis). At this time, the scanning distance of the laser beam in the x-axis direction substantially coincides with the distance Lx.

  Thereafter, the laser beam is repeatedly scanned in the order of the arrow 61a, the arrow 61b, the arrow 61c, and the arrow 61d.

JP 2002-240669 A

  FIG. 5 is a diagram showing in more detail an example of the position of the light spot when the laser beam is scanned as described above with reference to FIG.

  When scanning laser light in the direction of the arrow 61a and the direction of the arrow 61c in FIG. 4, it is necessary to drive the galvanometer scanner in both the x-axis direction and the y-axis direction. Therefore, in both galvanometer scanners, a dynamic friction force is applied to the movable portion of the bearing that supports the scanning rotation shaft. In general, the coefficient of dynamic friction is smaller than the coefficient of static friction. Therefore, when the galvanometer scanner is driven and the rotating shaft is rotating, the rotating shaft is not rotating without driving the galvanometer scanner. Susceptible to disturbances such as vibration. Therefore, when the laser beam is scanned in the direction of the arrow 61a and the direction of the arrow 61c, the vibration of the laser beam is not settled due to disturbance such as vibration, and the laser beam is likely to meander. As a result, a region where the laser beam (light spot) is not irradiated and the thin film is not peeled off is generated as indicated by the hatched portions in the ranges 71a to 71d in FIG.

  Further, when the scanning direction of the laser beam is switched from the direction of the arrow 61a to the direction of the arrow 61c via the direction of the arrow 61b, the response of the galvanometer scanner is delayed due to the inertia. As a result, at the end of the range 21 in FIG. 3, as shown in the range 71 e in FIG. 5, the positions of the light spots are not aligned, and the portion that remains without peeling off the thin film has a comb shape. As a result, when the thin film solar cell panel 11 is used for a long period of time, the risk that the film surface deteriorates or peels off from the portion processed on the comb teeth increases.

  This invention is made | formed in view of such a condition, and it is made to improve processing quality, suppressing the increase in the processing time of the edge deletion of a thin film solar cell panel.

  A laser processing apparatus according to one aspect of the present invention is a laser processing apparatus that peels a thin film from a substrate using a laser beam, in a predetermined range in a first direction and in a second direction orthogonal to the first direction. A processing unit including a scanning unit that scans the laser beam on the substrate within a predetermined range; and at least one of the processing unit and the substrate is moved, and a relative position between the processing unit and the substrate is at least the A moving means for moving in a first direction, and when peeling a thin film in a linear first region that is wider than the beam diameter of the laser light and extends in the first direction from the substrate, While moving the relative position between the processing unit and the substrate in the first direction by the moving unit, the scanning unit scans the laser beam in the advancing direction of the processing unit with respect to the substrate, First The irradiation position of the laser beam scans in the traveling direction in the area.

  In the laser processing apparatus according to one aspect of the present invention, when the thin film in the linear first region that is wider than the beam diameter of the laser light and extends in the first direction is peeled from the substrate, the processing unit and the substrate The laser beam is scanned in the advancing direction in which the processed portion advances with respect to the substrate while the relative position between them is moved in the first direction, and the irradiation position of the laser beam is scanned in the advancing direction within the first region.

  Therefore, processing quality can be improved while suppressing an increase in processing time for edge deletion of the thin-film solar cell panel.

  This scanning means is constituted by, for example, a galvanometer scanner. This moving means is comprised by a linear motor, a lifter, an actuator, etc., for example.

  After the laser beam is scanned in the traveling direction, the scanning unit further shifts the laser beam in the second direction and scans the laser beam in a direction opposite to the traveling direction, thereby moving the traveling direction. The laser light irradiation position can be scanned in a direction opposite to the traveling direction at a position adjacent to the laser light irradiation position when the laser light is scanned in the second direction.

  Thereby, the processing time of the edge deletion of a thin film solar cell panel can be shortened more.

  While the irradiation position of the laser beam is shifted in the second direction for each predetermined range in the first direction of the first region by the scanning unit, the traveling direction or the direction opposite to the traveling direction The thin films in each range can be peeled in order of the traveling direction.

  Thereby, the processing time of the edge deletion of a thin film solar cell panel can be shortened more.

  When the thin film in the linear second region that is wider than the beam diameter of the laser light and extends in the second direction is peeled off from the substrate, the moving means causes the relative between the processed portion and the substrate. While moving the position in the second direction, the scanning unit scans the laser beam in the traveling direction in which the processing unit advances with respect to the substrate, and sets the irradiation position of the laser beam in the second region. It is possible to scan in the traveling direction.

  Thereby, processing in both the first and second directions becomes possible.

  The cross section of the laser light incident on the substrate can be rectangular.

  Thereby, the area which overlaps an adjacent light spot can be made small, and the processing time of the edge deletion of a thin film solar cell panel can be shortened more.

  The scanning unit may include a first galvanometer scanner that scans laser light in a first direction and a second galvanometer scanner that scans laser light in a second direction.

  Thereby, the scanning of the laser beam can be performed accurately and at high speed.

  Laser oscillation means for oscillating the laser beam can be further provided.

  According to another aspect of the present invention, there is provided a laser processing apparatus including a processing unit including a scanning unit that scans the laser light in a first direction and a second direction orthogonal to the first direction on a substrate. When the thin film in the linear region that is wider than the beam diameter of the laser beam and extends in the first direction is peeled from the substrate, the relative position between the processed portion and the substrate is set by the moving means. While moving in the first direction, the scanning unit scans the laser beam in the traveling direction in which the processing unit advances with respect to the substrate, and scans the irradiation position of the laser beam in the traveling direction in the region. To do.

  In the laser processing method according to one aspect of the present invention, when the thin film in the linear region that is wider than the beam diameter of the laser beam and extends in the first direction is peeled off from the substrate, the relative relationship between the processed portion and the substrate is reduced. While the position is moved in the first direction, the laser beam is scanned in the advancing direction in which the processing portion advances with respect to the substrate, and the irradiation position of the laser beam is scanned in the advancing direction within the region.

  Therefore, processing quality can be improved while suppressing an increase in processing time for edge deletion of the thin-film solar cell panel.

  This scanning means is constituted by, for example, a galvanometer scanner.

  According to one aspect of the present invention, edge deletion of a thin film solar cell panel can be performed. In particular, according to one aspect of the present invention, it is possible to improve processing quality while suppressing an increase in processing time for edge deletion of a thin-film solar cell panel.

It is a figure for demonstrating the 1st example of the scanning method of a laser beam. It is a figure for demonstrating the 1st example of the scanning method of a laser beam. It is a figure for demonstrating the 2nd example of the scanning method of a laser beam. It is a figure for demonstrating the 2nd example of the scanning method of a laser beam. It is a figure for demonstrating the problem which generate | occur | produces with the scanning method of a 2nd laser beam. It is a perspective view which shows the structural example of the external appearance of the laser processing apparatus to which this invention is applied. It is a block diagram which shows the structural example of the circuit of the laser processing apparatus to which this invention is applied. It is a figure which shows the end surface of a rectangular optical fiber. It is a figure which shows the example of distribution of the intensity | strength of the light of the cross section of the multimode laser pulse before it introduce | transduces into a square optical fiber, and after being introduced and radiate | emitted. It is a figure which shows the structural example of a galvanometer scanner. It is a figure which shows the structural example of a galvanometer. It is a block diagram which shows the structural example of the control part of a laser processing apparatus. It is a flowchart for demonstrating the laser processing performed by the laser processing apparatus. It is a flowchart for demonstrating the detail of an edge deletion process. It is a figure which shows the processing order of edge deletion. It is a figure which shows the position and scanning direction of a light spot. It is a figure which shows the scanning direction of a laser beam.

Hereinafter, modes for carrying out the present invention (hereinafter referred to as embodiments) will be described. The description will be given in the following order.
1. Embodiment 2. FIG. Modified example

<1. Embodiment>
A configuration example of the laser processing apparatus 101 as an embodiment of the present invention will be described with reference to FIGS. The laser processing apparatus 101 is an apparatus for performing edge deletion of the thin film solar cell panel 102.

[External configuration example of laser processing equipment]
FIG. 6 is a perspective view showing a configuration example of the external appearance of the laser processing apparatus 101. The laser processing apparatus 101 includes a laser oscillator 111, a rectangular optical fiber 112, an optical unit 113, a gantry crane 114, a stage 115, and a pedestal 116. The laser oscillator 111 and the optical unit 113 are connected via a rectangular optical fiber 112. The optical unit 113 is provided on the front surface of the gantry crane 114. The gantry crane 114 is provided on the upper surface of the stage 115. The pedestal 116 is provided approximately at the center of the upper surface of the stage 115.

  Hereinafter, the width direction of the stage 115 is defined as the x-axis direction, and the direction from left to right is defined as the positive direction. The depth direction of the stage 115 is the y-axis direction, and the direction from the back to the front is the positive direction. Furthermore, the height direction of the stage 115 is defined as the z-axis direction, and the direction from the bottom to the top is defined as the positive direction.

  Laser light emitted from the laser oscillator 111 enters the optical unit 113 through the rectangular optical fiber 112. The optical unit 113 irradiates the thin film solar cell panel 102 placed on the pedestal 116 with laser light and scans the laser light on the thin film solar cell panel 102.

  The optical unit 113 can be translated in the x-axis direction by a linear motor 121 provided on the front surface of the gantry crane 114. Furthermore, the gantry crane 114 can be translated in the y-axis direction by linear motors 122 a and 122 b provided along the left and right sides of the upper surface of the stage 115. Then, by moving the optical unit 113 and the gantry crane 114, the irradiation position of the laser light on the thin-film solar cell panel 102 can be moved in the x-axis direction and the y-axis direction.

  Further, on the upper surface of the stage 115, conveyor belts 123a and 123b extending in the y-axis direction are provided on the left and right sides of the base 116, and the thin film solar cell panel 102 is conveyed in the y-axis direction by the conveyor belts 123a and 123b. Is done.

[Example of circuit configuration of laser processing equipment]
FIG. 7 is a block diagram illustrating a configuration example of a circuit of the laser processing apparatus 101. The laser oscillator 111 of the laser processing apparatus 101 is configured to include a pulse generator 151, a laser oscillator 152, an attenuator (ATT) 153, a collimator lens 154, and a lens 155. The optical unit 113 of the laser processing apparatus 101 is configured to include a beam expander 171, galvanometer scanners 172 a and 172 b, and an fθ lens 173.

  The pulse generator 151 generates a pulse signal having a predetermined frequency (hereinafter referred to as an emission command signal), and supplies the generated emission command signal to the laser oscillator 152.

  The laser oscillator 152 is constituted by a multi-mode Q-SW laser oscillator using, for example, a laser diode (hereinafter referred to as LD) as an excitation light source and Nd: YAG as a laser medium. The laser oscillator 152 emits pulsed laser light whose transverse mode of the fundamental wave (wavelength is 1064 nm) is multimode in synchronization with the emission command signal supplied from the pulse generator 151. Laser light emitted from the laser oscillator 152 is attenuated by the attenuator 153, collimated by the collimator lens 154, and enters the lens 155. The lens 155 collects the laser light and introduces it into the rectangular optical fiber 112.

  Note that the attenuation amount of the attenuator 153 is variable and can be set to an arbitrary value.

  The rectangular optical fiber 112 is composed of a multimode optical fiber. FIG. 8 shows the end face (incident surface or exit surface) of the rectangular optical fiber 112. Thus, the cross section of the entrance or exit port 112A of the rectangular optical fiber 112 is rectangular. Accordingly, the laser light that has passed through the rectangular optical fiber 112 is emitted from the rectangular optical fiber 112 with its cross-section formed into a rectangular shape.

  Further, as described above, the laser light emitted from the laser oscillator 152 is a multimode laser pulse, and the light intensity distribution in the cross section of each laser pulse before being introduced into the rectangular optical fiber 112 is shown in FIG. As shown on the left side of, there are several peaks. And since the multimode laser pulse has low coherency, the intensity distribution of the light in the cross section of each laser pulse emitted after multiple reflection in the rectangular optical fiber 112 is shown on the right side of FIG. Thus, there is no interference fringe and the peak is almost flat. That is, the intensity of the light in the cross section of each laser pulse at the emission end face of the rectangular optical fiber 112 is substantially uniform regardless of the distance from the center. Note that a laser pulse with uniform light intensity in a cross section can reduce, for example, processing unevenness in a portion irradiated with the pulse, and is suitable for edge deletion.

  In this manner, the laser processing apparatus 101 has a simple configuration in which a multimode laser pulse is passed through the rectangular optical fiber 112 without using an expensive apparatus such as a homogenizer and a large loss of optical power. It is possible to efficiently obtain a laser pulse having a uniform light intensity in a cross section suitable for the operation.

  Returning to FIG. 7, the laser light emitted from the rectangular optical fiber 112 enters the optical unit 113. The laser light incident on the optical unit 113 is expanded into a rectangular beam by a beam expander 171 and becomes a parallel light beam. The laser light emitted from the beam expander 171 is reflected in the direction of the fθ lens 173 by the galvanometer scanners 172a and 172b, enters the thin film solar cell panel 102 through the fθ lens 173, and is processed on the thin film solar cell panel 102. The image is formed at.

[Example configuration of galvanometer scanner]
Here, a configuration example of the galvanometer scanners 172a and 172b will be described with reference to FIGS.

  As shown in FIG. 10, the galvanometer scanner 172a includes a galvanometer 181a, a rotation shaft 182a, and a mirror 183a. The laser light emitted from the beam expander 171 enters the mirror 183a and is reflected by the mirror 183a in the direction of the galvanometer scanner 172b. The mirror 183a can rotate about the rotation shaft 182a based on the control of the galvanometer 181a, and can change the incident angle of the laser beam. Then, the laser beam is scanned in the x-axis direction on the thin film solar cell panel 102 by changing the incident angle of the laser beam to the mirror 183a and changing the reflection direction of the laser beam.

  The galvanometer scanner 172b has the same configuration as the galvanometer scanner 172a, and includes a galvanometer 181b, a rotating shaft 182b, and a mirror 183b. The laser beam reflected by the mirror 183a of the galvanometer scanner 172a enters the mirror 183b and is reflected by the mirror 183b in the direction of the fθ lens 173. The mirror 183b rotates around the rotation shaft 182b based on the control of the galvanometer 181b, and can change the incident angle of the laser beam. Then, the laser light is scanned in the y-axis direction on the thin film solar cell panel 102 by changing the incident angle of the laser light to the mirror 183b and changing the reflection direction of the laser light.

  FIG. 11 shows a configuration example of the galvanometer 181a. The galvanometer 181a includes a movable coil 201, a helical spring 202, and permanent magnets 203N and 203S.

  The movable coil 201 is supported by the rotary shaft 182a and is placed in a magnetic field generated between the permanent magnet 203N and the permanent magnet 203S. The rotating shaft 182a is connected to the helical spring 202, and a mirror 183a (not shown) is attached to one end, and the other end is supported by a bearing (not shown).

  When a current is passed through the movable coil 201 in the magnetic field, the movable coil 201 rotates about the rotation shaft 182a in the direction opposite to the direction in which the helical spring 202 pulls the rotation shaft 182a. Then, when the force for rotating the movable coil 201 and the force for the helical spring 202 to pull the rotating shaft 182a become equal, the rotation of the rotating shaft 182a stops. In this manner, the angle of the mirror 183a can be set to an angle corresponding to the magnitude of the current flowing through the movable coil 201, and the reflection direction of the laser light by the mirror 183a can be changed. Therefore, by controlling the current flowing through the movable coil 201, the reflection direction of the laser beam by the mirror 183a can be controlled, and the laser beam can be scanned.

  By the way, when the electric current which flows into the movable coil 201 is constant, since the rotating shaft 182a does not rotate, a static friction force acts on the movable part of the bearing which supports the rotating shaft 182a. On the other hand, when the current flowing through the movable coil 201 is changed, the rotating shaft 182a rotates, and a dynamic friction force acts on the movable portion of the bearing that supports the rotating shaft 182a. As described above, since the dynamic friction coefficient is generally smaller than the static friction coefficient, the influence of disturbances such as vibration is more effective when the rotation shaft 182a is rotating than when the rotation shaft 182a is not rotating. Is easily received by the rotary shaft 182a. That is, when the mirror 183a is rotated around the rotation shaft 182a, the mirror 183a is more likely to be shaken due to disturbance than when the mirror 183a is fixed. This disturbance is generated by, for example, vibration when the gantry crane 114 is driven by the linear motors 122a and 122b.

  Note that the galvanometer 181b of the galvanometer scanner 172b has the same configuration as the galvanometer 181a, and a description thereof will be omitted because it will be repeated.

  As described above, the mirror 183a of the galvanometer scanner 172a rotates about the rotation axis 182a, and the mirror 183b of the galvanometer scanner 172b rotates about the rotation axis 182b, so that the incident position and incidence of the laser light on the fθ lens 173 are obtained. The angle changes. Then, the imaging position of the laser light on the processed surface of the thin-film solar battery panel 102 moves in the horizontal direction according to the change in the incident angle and the incident position on the fθ lens 173. That is, the irradiation position of the laser light on the thin-film solar battery panel 102 is scanned by the galvanometer scanners 172a and 172b.

  Returning to FIG. 7, the thin-film solar battery panel 102 is a single-type thin-film solar battery panel. From the top of the figure, a transparent electrode layer 102B made of TCO such as a glass transparent substrate 102A, ITO, SnO2, ZnO, a The semiconductor layer 102C made of -Si and the back electrode layer 102D made of an Ag electrode are laminated in this order. Then, the transparent electrode layer 102B to the back electrode layer 102D are removed by the laser light.

[Configuration Example of Control Unit of Laser Processing Apparatus 101]
FIG. 12 is a block diagram illustrating a configuration example of the control unit 251 that controls the operation of the laser processing apparatus 101. The control unit 251 is realized, for example, when a processor such as a CPU (Central Processing Unit) executes a predetermined control program. The control unit 251 is configured to include an output control unit 261, a drive control unit 262, and a scanning control unit 263.

  The output control unit 261 controls the laser oscillator 111 and controls the intensity of the laser light emitted from the laser oscillator 111, the emission timing, and the like.

  The drive control unit 262 drives the linear motor 121 to control the position of the optical unit 113 in the x-axis direction. The drive control unit 262 controls the position of the optical unit 113 in the y-axis direction by driving the linear motors 122a and 122b and controlling the position of the gantry crane 114 in the y-axis direction. Further, the drive control unit 262 drives the conveyor belts 123a and 123b to control the position of the thin film solar cell panel 102 in the y-axis direction.

  The scanning control unit 263 drives the galvanometer scanners 172a and 172b to control the scanning of the laser light.

  Note that the output control unit 261, the drive control unit 262, and the scanning control unit 263 share information such as the operation state of each other.

[Laser processing]
Next, the laser processing performed by the laser processing apparatus 101 will be described with reference to the flowchart of FIG.

  In step S1, the drive control unit 262 determines whether the thin-film solar battery panel 102 has been inserted. For example, the drive control unit 262 detects whether or not the thin-film solar battery panel 102 is installed on the conveyor belts 123a and 123b based on information from a sensor (not shown) provided on the stage 115. When the thin-film solar battery panel 102 is not installed on the conveyor belts 123a and 123b, the drive control unit 262 determines that the thin-film solar battery panel 102 is not inserted, and the thin-film solar panel is placed on the conveyor belts 123a and 123b. When the battery panel 102 is installed, it determines with the thin film solar cell panel 102 having been inserted. This determination process is repeated until it is determined that the thin-film solar battery panel 102 has been inserted. If it is determined that the thin-film solar battery panel 102 has been inserted, the process proceeds to step S2.

  In step S <b> 2, the laser processing apparatus 101 starts pulling in the thin film solar cell panel 102. That is, the drive control unit 262 starts the conveyance of the thin film solar battery panel 102 in the negative direction of the y-axis by driving the conveyance belts 123a and 123b.

  In step S <b> 3, the drive control unit 262 determines whether or not the thin-film solar battery panel 102 has been pulled to the position of the pedestal 116. For example, the drive control unit 262 determines whether the thin-film solar battery panel 102 has been pulled to the position of the pedestal 116 based on information from a sensor (not shown) provided on the stage 115. This determination process is repeated until it is determined that the thin-film solar battery panel 102 has been pulled to the position of the pedestal 116. If it is determined that the thin-film solar battery panel 102 has been pulled to the position of the pedestal 116, the process proceeds to step S4. move on.

  In step S <b> 4, the laser processing apparatus 101 installs the thin film solar cell panel 102 on the pedestal 116. That is, the drive control unit 262 stops the driving of the transport belts 123a and 123b, and controls the lifter (not shown), for example, to install the thin film solar cell panel 102 on the pedestal 116.

  In step S5, the laser processing apparatus 101 performs an edge deletion process. The details of the edge deletion process will be described later with reference to FIG.

  In step S <b> 6, the laser processing apparatus 101 starts pulling out the thin film solar cell panel 102. That is, the drive control unit 262 controls, for example, a lifter (not shown), installs the thin-film solar battery panel 102 on the transport belts 123a and 123b, and drives the transport belts 123a and 123b, thereby thin-film solar battery panels. The conveyance in the positive direction of the y-axis 102 is started.

  In step S <b> 7, the drive control unit 262 determines whether or not the drawing of the thin film solar cell panel 102 is completed. For example, the drive control unit 262 determines whether or not the drawing of the thin-film solar battery panel 102 has been completed based on information from a sensor (not shown) provided on the stage 115. This determination process is repeated until it is determined that the drawing of the thin-film solar battery panel 102 has been completed. When it is determined that the drawing of the thin-film solar battery panel 102 has been completed, the laser processing process ends.

[Details of edge deletion processing]
Next, the details of the edge deletion process in step S5 in FIG. 13 will be described with reference to the flowchart in FIG.

  In step S51, the drive control unit 262 moves the irradiation position of the laser beam to the start position of the side to be processed next.

  FIG. 15 shows an example of the processing order when edge deletion is performed on the thin-film solar battery panel 102. In this example, edge deletion is performed in the order of arrow 305a, arrow 305b, arrow 305c, and arrow 305d.

  That is, the region 302a around the side 301a of the thin-film solar cell panel 102 is irradiated with laser light, and the thin film in the linear region 303a having a width wider than the beam diameter of the laser light indicated by the oblique lines in the region 302a is peeled off. The Next, the region 302b around the side 301b of the thin-film solar battery panel 102 is irradiated with laser light, and the thin film in the linear region 303b having a width wider than the beam diameter of the laser light, which is indicated by oblique lines in the region 302b, is peeled off. Is done. Next, the region 302c around the side 301c of the thin-film solar battery panel 102 is irradiated with laser light, and the thin film in the linear region 303c having a width wider than the beam diameter of the laser light, which is indicated by oblique lines in the region 302c, is peeled off. Is done. Finally, the region 302d around the side 301d of the thin-film solar battery panel 102 is irradiated with laser light, and the thin film in the linear region 303d having a width wider than the beam diameter of the laser light, which is indicated by diagonal lines in the region 302d. Is peeled off.

  When performing edge deletion of the region 303a, laser light irradiation is started from the start position 304a at the lower left corner of the range 302a. In addition, when performing edge deletion of the region 303b, laser light irradiation is started from the start position 304b of the upper left corner of the range 302b. Furthermore, when performing edge deletion of the region 303c, laser beam irradiation is started from the start position 304c at the upper right corner of the range 302c. In addition, when performing edge deletion of the region 303d, laser beam irradiation is started from the start position 304d at the lower right corner of the range 302d.

  Therefore, in the present embodiment, since the side 301a is first processed, the drive control unit 262 drives the linear motor 121 and the linear motors 122a and 122b, and the laser light emitted from the optical unit 113 is emitted. The optical unit 113 and the gantry crane 114 are moved to a position where the start position 304a is irradiated.

  In step S52, the drive control unit 262 starts to move the optical unit 113 along the side to be processed. In this case, the drive control unit 262 drives the linear motor 121 to start the movement of the optical unit 113 in the positive direction of the x axis. Thereby, the movement of the optical unit 113 in the direction of the arrow 305a (the longitudinal direction of the region 303a) along the side 301a to be processed first is started.

  Hereinafter, a direction in which the optical unit 113 moves with respect to the thin film solar cell panel 102 is referred to as a main scanning direction. Hereinafter, a direction perpendicular to the main scanning direction on the thin film solar cell panel 102 is referred to as a sub-scanning direction. Therefore, when performing edge deletion of the region 303a, the main scanning direction is the positive direction of the x-axis, and the sub-scanning direction is the y-axis direction. Further, hereinafter, the main scanning direction is also referred to as a row direction, and the sub-scanning direction is also referred to as a column direction.

  In step S <b> 53, the laser oscillator 111 starts outputting laser light based on the control of the output control unit 261. Thereby, irradiation of the laser beam to the thin film solar cell panel 102 is started.

  In step S54, the scanning control unit 263 starts scanning with laser light.

  Here, with reference to FIG. 16 and FIG. 17, the detail of the scanning method of a laser beam is demonstrated. FIG. 16 shows the position of the light spot and the scanning direction within the range 302a. FIG. 17 shows the scanning direction of the laser beam when the light spot is scanned as shown in FIG.

  As described above, the laser beam irradiation is started from the start position 304a. Then, the scanning control unit 263 drives the galvanometer scanner 172a to scan the laser beam in the direction of the arrow 331a in FIG. 17 (the positive direction of the x axis), that is, the main scanning direction. The scanning distance at this time is set, for example, in the vicinity of the maximum distance at which the galvanometer scanner 172a can scan the laser beam in the x-axis direction. As a result, the light spot is scanned in the direction of the arrow 311a in FIG. 16, that is, in the main scanning direction. At this time, the laser beam is irradiated so that the ends of the light spots adjacent in the x-axis direction partially overlap.

  Next, the scanning control unit 263 drives the galvanometer scanner 172b and scans the laser beam in the direction of the arrow 311a in the direction of the arrow 331b (the negative direction of the y axis) in FIG. The laser beam is scanned up to the next row. Thereby, the position of the light spot is shifted by one line in the negative direction of the y-axis. At this time, since the optical unit 113 is moved in the positive direction of the x-axis, the light spot is oblique in the positive direction of the x-axis and in the negative direction of the y-axis, as indicated by the arrow 311b. Scanned. Also, the end of the light spot in the first row scanned in the direction of the arrow 311a and the end of the light spot in the second row scanned in the direction of the arrow 311c partially overlap each other. The position of the light spot is set.

  Next, the scanning control unit 263 drives the galvanometer scanner 172a to scan the laser beam in the direction of the arrow 331c in FIG. 17 (the negative direction of the x axis), that is, in the direction opposite to the main scanning direction. The scanning distance at this time is set to substantially the same distance as when the laser beam is scanned in the direction of the arrow 331a. As a result, the light spot is scanned in the direction of the arrow 311c in FIG. 16, that is, in the direction opposite to the main scanning direction, at a position adjacent to the position of the light spot in the first row. At this time, the laser beam is irradiated so that the ends of the light spots adjacent in the x-axis direction partially overlap.

  Next, the scanning control unit 263 drives the galvanometer scanner 172b and scans the laser beam in the direction of the arrow 311c in the direction of the arrow 331d (the negative direction of the y-axis) in FIG. The laser beam is scanned up to the next row. As a result, the light spot is scanned in the direction of the arrow 311d that is substantially the same as the arrow 311b in FIG. 16, and the position of the light spot is shifted by one line in the negative direction of the y-axis. Also, the end of the light spot in the second row scanned in the direction of the arrow 311c and the end of the light spot in the third row scanned in the direction of the arrow 311e partially overlap each other. The position of the light spot is set.

  Thereafter, the laser beam is scanned in the order of arrow 331e, arrow 331f,..., Arrow 331k in FIG. That is, after the laser beam is scanned in the main scanning direction, the process of shifting to the adjacent row in the sub-scanning direction, scanning in the direction opposite to the main scanning direction, and then shifting to the adjacent row in the sub-scanning direction is repeated. Accordingly, the light spot is scanned in the order of the arrow 311e, the arrow 311f,..., The arrow 311k in FIG. In other words, the light spot is alternately scanned line by line in the main scanning direction or in the direction opposite to the main scanning direction while being shifted line by line in the sub-scanning direction.

  Then, after the scanning of the laser beam in the direction of the arrow 331k is completed, the scanning control unit 263 drives the galvanometer scanner 172b to perform the laser in the direction of the arrow 331l (the positive direction of the y axis), that is, the sub-scanning direction. The light is scanned, and the position of the light spot in the y-axis direction is moved to the position of the first row. At this time, since the optical unit 113 is moved in the positive direction of the x-axis, the light spot is an oblique direction in the positive direction of the x-axis and in the positive direction of the y-axis as indicated by an arrow 311l. Scanned. Further, the scanning control unit 263 scans the laser beam so that the position of the light spot when the scanning in the direction of the arrow 311l is completed substantially coincides with the position of the end of the light spot scanned in the direction of the arrow 311a. Control the speed.

  Hereinafter, the region where the thin film is peeled by scanning the laser beam once in the order of arrows 331a, 331b,.

  Thereafter, similarly, laser beams are scanned in the order of arrows 331a, 331b,..., 331l in FIG. 17, and light spots are scanned in the order of arrows 312a, 312b,. Similar scanning is repeated until the thin film in the region 303a is completely peeled off. As a result, the light spot is alternately shifted every row in the main scanning direction or in the direction opposite to the main scanning direction in each processing block until the thin film of the region 303a is peeled off. The thin film in each processing block is peeled off in the order of the main scanning direction.

  By the way, when the laser beam is scanned in the main scanning direction and in the direction opposite to the main scanning direction, the galvanometer scanner 172a is driven, and the dynamic frictional force acts on the movable portion of the bearing of the galvanometer scanner 172a, while the galvanometer scanner 172b is stopped. The static frictional force is applied to the movable part of the bearing of the galvanometer scanner 172a. Accordingly, the rotating shaft 182b of the galvanometer scanner 172b is not easily affected by disturbances such as vibration, and the vibration of the laser beam in the y-axis direction is stabilized. As a result, the position of the light spot does not meander and is substantially straight in the x-axis direction. Accordingly, since the rectangular light spot is scanned in a straight line in the main scanning direction at the end of the region 303a (between the portion where the thin film is peeled off and the portion where the thin film is not peeled off), the end of the region 303a is not uneven. , Almost aligned. Further, in the region 303a, a region where the laser beam is not irradiated and the thin film is not peeled off can be eliminated.

  Further, the scanning direction of the laser light is changed from the main scanning direction (for example, the direction of arrow 331a in FIG. 17) to the reverse direction of the main scanning direction (for example, the direction of arrow 331c in FIG. 17), or the reverse direction of the main scanning direction. When reversing from the main scanning direction (for example, the direction of arrow 331e in FIG. 17) from the direction (for example, the direction of arrow 331c in FIG. 17), both the galvanometer scanner 172a and the galvanometer scanner 172b are driven in a short time. Therefore, due to the same cause as the phenomenon described above with reference to FIG. However, as shown in a range 313 in FIG. 16, by overlapping the ends of adjacent processing blocks, the thin film remaining on the comb teeth is peeled off, and this problem can be solved.

  Furthermore, as in the scanning method described above with reference to FIGS. 3 and 4, the area where adjacent light spots overlap can be reduced. Furthermore, by making the cross section (light spot) of the laser light rectangular, the area over which the adjacent light spots overlap can be further reduced as compared with the case of a circle or ellipse. As a result, the processing time can be shortened.

  Returning to FIG. 14, in step S55, the scanning control unit 263 determines whether or not the processing of the side being processed is completed. The determination process of step S55 is repeatedly executed until it is determined that the processing of the side being processed has been completed. If it is determined that the processing of the side being processed has been completed, the processing proceeds to step S56.

  In step S <b> 56, the laser oscillator 111 stops the output of the laser light based on the control of the output control unit 261. Thereby, irradiation of the laser beam to the thin film solar cell panel 102 is stopped.

  In step S57, the scanning control unit 263 determines whether or not all sides have been processed. If it is determined that all the sides have not been processed, the process returns to step S51.

  Thereafter, the processes in steps S51 to S57 are repeatedly executed until it is determined in step S57 that all the sides have been processed. Accordingly, the laser beam is irradiated in the order of the range 302b, the range 302c, and the range 302d by a method similar to the scanning method described above with reference to FIGS. 16 and 17, and the thin film is sequentially formed in the region 303b, the region 303c, and the region 303d. Is peeled off.

  The main scanning direction is the direction of the arrow 305b (the positive direction of the y axis) when processing the side 301b, and the direction of the arrow 305c (the negative direction of the x axis) when processing the side 301c. When processing the side 301d, the direction of the arrow 305d (the negative direction of the y-axis) changes. Accordingly, the order of driving the galvanometer scanners 172a and 172b and the scanning direction are adjusted according to the change in the main scanning direction, and the scanning direction of the laser light is adjusted.

  For example, when processing the side 301b, the scanning direction of the laser light is adjusted so that the direction of the arrow 331a in FIG. 17 is the positive direction of the y-axis and the direction of the arrow 331b is the positive direction of the x-axis. The Then, the light spot is scanned in the region 302b so that the direction of the arrow 311a in FIG. 16 is the positive direction of the y-axis and the direction of the arrow 311b is the positive direction of the x-axis. When processing the side 301c, the scanning direction of the laser light is adjusted so that the direction of the arrow 331a is the negative direction of the x axis and the direction of the arrow 331b is the positive direction of the y axis. Then, the light spot is scanned in the region 302c so that the direction of the arrow 311a in FIG. 16 is the negative direction of the x-axis and the direction of the arrow 311b is the positive direction of the y-axis. Further, when processing the side 301d, the scanning direction of the laser light is adjusted so that the direction of the arrow 331a is the negative direction of the y-axis and the direction of the arrow 331b is the negative direction of the x-axis. Then, the light spot is scanned in the region 302d so that the direction of the arrow 311a in FIG. 16 is the negative direction of the y-axis and the direction of the arrow 311b is the negative direction of the x-axis.

  On the other hand, if it is determined in step S57 that all the sides have been processed, the edge deletion process ends.

  As described above, the processing quality can be improved while suppressing an increase in the processing time of the edge deletion of the thin-film solar battery panel 102.

<2. Modification>
In the above description, the example in which the present invention is applied in the case of performing edge deletion of the thin film solar cell panel 102 has been described. In the case of peeling, in other words, the present invention can also be applied to the case of peeling a thin film in a rectangular region from a substrate using laser light.

  Moreover, in the above description, the example which moves the relative position between the thin film solar cell panel 102 and the optical part 113 is shown by moving the position of the optical part 113, with the position of the thin film solar cell panel 102 fixed. However, the relative position between the thin-film solar cell panel 102 and the optical unit 113 is changed by moving the position of the thin-film solar cell panel 102 or both of them while keeping the position of the optical unit 113 fixed. You may make it move.

  Furthermore, in the above description, the example in which the cross section of the laser light is rectangular has been shown, but a shape other than a rectangle, for example, a circle or an ellipse may be used.

  In the above description, the example in which the laser light is scanned by the galvanometer scanners 172a and 172b is shown, but the laser light may be scanned by using other scanning means.

  The embodiment of the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the gist of the present invention.

DESCRIPTION OF SYMBOLS 101 Laser processing apparatus 102 Thin film solar cell panel 111 Laser oscillator 112 Rectangular optical fiber 113 Optical part 114 Gantry crane 115 Stage 116 Base 121 Linear motor 122a, 122b Linear motor 123a, 123b Conveyor belt 171 Beam expander 172a, 172b Galvanometer scanner 173 fθ Lenses 181a, 181b Galvanometers 182a, 182b Rotating shafts 183a, 183b Mirror 251 Control unit 261 Output control unit 262 Drive control unit 263 Scan control unit

Claims (8)

In a laser processing apparatus that peels a thin film from a substrate using laser light,
A processing unit including a scanning unit that scans the laser beam on the substrate in a predetermined range in a first direction and in a predetermined range in a second direction orthogonal to the first direction;
Moving means for moving at least one of the processed part and the substrate and moving a relative position between the processed part and the substrate in at least the first direction;
When the thin film in the linear first region that is wider than the beam diameter of the laser light and extends in the first direction is peeled off from the substrate, the moving means may cause relative movement between the processed portion and the substrate. While moving the position in the first direction, the scanning unit scans the laser beam in the traveling direction in which the processing unit advances with respect to the substrate, and sets the irradiation position of the laser beam in the first region. Scanning in the traveling direction. A laser processing apparatus. After the laser beam is scanned in the traveling direction, the scanning unit further shifts the laser beam in the second direction and scans the laser beam in a direction opposite to the traveling direction, thereby moving the traveling direction. The laser light irradiation position is scanned in a direction opposite to the traveling direction at a position adjacent to the laser light irradiation position and the second direction when the laser light is scanned. The laser processing apparatus according to 1. While the irradiation position of the laser beam is shifted in the second direction for each predetermined range in the first direction of the first region by the scanning unit, the traveling direction or the direction opposite to the traveling direction The laser processing apparatus according to claim 2, wherein the thin film in each range is peeled in order of the traveling direction. When the thin film in the linear second region that is wider than the beam diameter of the laser light and extends in the second direction is peeled off from the substrate, the moving means causes the relative between the processed portion and the substrate. While moving the position in the second direction, the scanning unit scans the laser beam in the traveling direction in which the processing unit advances with respect to the substrate, and sets the irradiation position of the laser beam in the second region. The laser processing apparatus according to claim 1, wherein scanning is performed in the traveling direction. The laser processing apparatus according to claim 1, wherein a cross section of the laser light incident on the substrate is rectangular. The scanning means includes
A first galvanometer scanner that scans the laser light in the first direction;
The laser processing apparatus according to claim 1, further comprising: a second galvanometer scanner that scans the laser light in the second direction. The laser processing apparatus according to claim 1, further comprising laser oscillation means for oscillating the laser light. A laser processing apparatus comprising a processing unit including a scanning unit that scans the laser light in a first direction and a second direction orthogonal to the first direction on a substrate.
When the thin film in the linear region that is wider than the beam diameter of the laser light and extends in the first direction is peeled off from the substrate, the moving unit sets the relative position between the processed portion and the substrate. While moving in the first direction, the scanning means scans the laser beam in the advancing direction in which the processed portion advances with respect to the substrate, and scans the irradiation position of the laser beam in the advancing direction in the region. The laser processing method characterized by the above-mentioned.

Images