JP2011031248A - Laser beam machining apparatus and laser beam machining method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a laser beam machining apparatus and a laser beam machining method, by which high-quality working is carried out. <P>SOLUTION: This laser beam machining apparatus includes: a laser beam source 10 from which a laser beam is emitted; a moving device 30 for moving an object to be machined inside and outside a machining region; an optical system including a light deflector for scanning a laser beam 50 emitted from the laser beam source so that the incident position is moved on the object to be machined which is moved inside the machining region with the moving device; a first imaging device 18 for picking up the image of the object to be machined which is moved by the moving device; and a controller for controlling the motion of the light deflector so that the laser beam emitted from the laser beam source is made incident on a target incident position by deriving the target incident position indicating a position where the laser beam emitted from the laser beam source should be made incident onto the object to be machined which is moved in side the machining region on the basis of the relative positional relationship between a machined mark of the object to be machined, which is picked up with the first image device and a pattern which is formed before irradiation of the laser beam. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a laser processing apparatus and a laser processing method for performing processing by irradiating a workpiece with a laser beam.

  With reference to FIGS. 3A and 3B, a conventional technique of patterning performed by irradiating a laser beam will be described.

  FIG. 3A is a schematic diagram of a laser processing apparatus used for patterning. A pulsed laser beam 50 is emitted from the laser light source 10. The light intensity of the pulse laser beam 50 is attenuated by the attenuator 11, the cross-sectional shape is shaped by the mask 12, the light passes through the focus lens 13 and the dichroic mirror 14, and enters the galvano scanner 15. Scanned up.

  The workpiece 40 is, for example, a film substrate. The workpiece conveyance device 30 can move the work area of the workpiece 40 in the y direction in the figure by unwinding and winding the workpiece 40. Irradiation of the workpiece 40 with the pulse laser beam 50 is performed in a state where the processing table 20 attracts the workpiece 40. By displacing the focus lens 13 in the optical axis direction of the pulse laser beam 50 by the lens moving mechanism 13a, the pulse laser beam 50 is incident on the work 40 with a focus regardless of the incident position.

  Light traveling on a path opposite to the pulse laser beam 50 incident on the workpiece 40 is reflected by the dichroic mirror 14 via the galvano scanner 15 and received by the CCD camera 16. As a result, an image near the incident position of the pulse laser beam 50 can be obtained. The workpiece 40 is moved in the z direction in the figure by the processing table 20 and the CCD camera 16 is focused. The optical axis of the laser beam emitted from the laser light source 10 coincides with the optical axis of the light incident on the CCD camera 16. Moreover, both coordinate systems are matched by calibration. By using the galvano scanner 15, the pulse laser beam 50 can be incident on an arbitrary position of the workpiece 40. Similarly, the CCD camera 16 can image an arbitrary position on the workpiece 40 via the galvano scanner 15. Data of an image photographed by the CCD camera 16 is transmitted to the control device 17 and used for control of laser patterning processing.

  FIG. 3B is a schematic plan view showing a part of the workpiece 40. The workpiece 40 is a workpiece in which an Ag film having a thickness of 100 nm to 300 nm is formed on a polyimide film, and is prepared as a roll body wound in a roll shape. The workpiece 40 is wound up in the y direction by the workpiece conveyance device 30. It is done. A plurality of patterning areas 40 a are defined in the length direction (winding direction) of the workpiece 40. In each patterning area 40a, a plurality of primary patterning lines 40b are formed in a straight line in the length direction of the workpiece 40 (direction parallel to the y direction) and in the direction perpendicular to the workpiece 40 (direction parallel to the x direction). Has been. The number of primary patterning lines 40b formed along the length direction of the workpiece 40 is, for example, 50, and the number of primary patterning lines 40b formed along the direction orthogonal to the length direction is, for example, five. The coordinates of these primary patterning lines 40b are given by, for example, CAD data. The pulse laser beam 50 emitted from the laser light source 10 is irradiated onto the primary patterning line 40b, and Ag film removal processing (patterning processing) is performed so as to trace the primary patterning line 40b.

  In the patterning process, first, coordinates of end points of the primary patterning line 40b from the CAD data, and a plurality of intersection points of the primary patterning line 40b extending in the x direction and the primary patterning line 40b extending in the y direction are used. Find the coordinates. Next, the galvano scanner 15 is operated, the CCD camera 16 picks up the end points and intersections and performs image processing to perform measurement, obtains a deviation, and obtains the coordinates of the actual intersection. Then, the position coordinates (processing target line) connecting the actual intersections obtained by measurement are calculated, and the laser beam is irradiated toward the position coordinates (processing target line).

  However, there is a difference between the laser coordinate system and the CCD camera coordinate system due to changes over time. In this laser patterning method, there is a gap between the laser beam incident target position (processing target line) and the actual incident position. Errors occur, and it is difficult to perform patterning with high accuracy.

  An invention of a laser processing method and a laser processing apparatus for processing a secondary patterning line at high speed by accurately irradiating a laser beam based on a primary patterning line formed on a substrate is disclosed (for example, Patent Document 1).

  Also, a laser processing method and a laser processing apparatus that perform processing while monitoring a position different from the irradiation position of the laser beam during laser patterning and correcting a target incident position of the laser beam defined before the processing. (For example, refer to Patent Document 2).

JP 2005-81392 A JP 2009-6339 A

  An object of the present invention is to provide a laser processing apparatus capable of performing high-quality processing.

  Moreover, it is providing the laser processing method which can perform a high quality process.

  According to one aspect of the present invention, a laser light source that emits a laser beam, a moving device that moves an object to be processed into and out of a processing region, and a laser beam emitted from the laser light source, the incident position of which moves An optical system including an optical deflector that scans so as to move on the processing object moved into the processing region by the apparatus, a first image sensor that images the processing object moved by the moving device, and Based on the relative positional relationship between the processing trace of the processing object photographed by the first image sensor and the pattern formed before the laser beam irradiation, the laser beam emitted from the laser light source is converted into the processing region. Deriving a target incident position representing the position to be incident on the workpiece moved inward, and controlling the operation of the optical deflector so that the laser beam is incident on the target incident position The laser processing apparatus is provided with a that controller.

  According to another aspect of the present invention, (a) a step of causing a laser beam to be incident on a first processing region where a pattern is formed and processing the first processing region; ) A step of imaging the first processed region processed in the step (a); and (c) a processing trace of the first processed region imaged in the step (b) and the pattern. A step of deriving a target incident position representing a position at which the laser beam is to be incident on a second region to be processed different from the first region to be processed based on the relative positional relationship; and (d) the step (c) And a step of scanning the laser beam so as to be incident on the target incident position derived in step (2) and causing the laser beam to enter the second region to be processed.

  ADVANTAGE OF THE INVENTION According to this invention, the laser processing apparatus which can perform a high quality process can be provided.

  In addition, a laser processing method capable of performing high-quality processing can be provided.

It is the schematic which shows the laser processing apparatus by an Example. (A)-(C) are the figures for demonstrating the laser processing method by an Example. (A) is a schematic view of a laser processing apparatus used for patterning, and (B) is a schematic plan view showing a part of the workpiece 40.

  FIG. 1 is a schematic diagram illustrating a laser processing apparatus according to an embodiment. The laser processing apparatus according to the embodiment includes a laser light source 10, an attenuator 11, a mask 12, a focus lens 13, a lens moving mechanism 13a, a dichroic mirror 14, a galvano scanner 15, a CCD camera 16, 18, a control device 17, a processing table 20, and A work conveying device 30 is included.

  The laser light source 10 receives a trigger signal sent from the control device 17 and emits a pulsed laser beam 50. The laser light source 10 includes, for example, an Nd: YAG laser oscillator and a nonlinear optical crystal. The pulse laser beam 50 is, for example, a second harmonic of an Nd: YAG laser.

  The pulse laser beam 50 is incident on the mask 12 after the light intensity is attenuated by the attenuator 11. The mask 12 has a light transmitting region and a light shielding region, and shapes the cross-sectional shape of the pulse laser beam 50. The pulse laser beam 50 whose cross-sectional shape is shaped by the mask 12 is collected by the focus lens 13, passes through the dichroic mirror 14, and enters the galvano scanner 15.

  The galvano scanner 15 is configured to include two oscillating mirrors, and can receive a control signal from the control device 17 and scan and emit a pulsed laser beam 50 in a two-dimensional direction. The emission direction of the pulse laser beam 50 is changed by the galvano scanner 15 and is incident on the workpiece 40 on the processing table 20. By using the galvano scanner 15, the pulse laser beam 50 can be incident on an arbitrary position of the workpiece 40.

  The workpiece 40 is a film-like substrate in which an Ag film having a thickness of 100 nm to 300 nm is formed on a polyimide film as shown in FIG. 3B, for example, and is prepared as a roll body wound in a roll shape. The pulse laser beam 50 is applied to the Ag film of the workpiece 40, and laser patterning is performed to remove the Ag film.

  The workpiece conveyance apparatus 30 can move the to-be-processed area | region (patterning area) of the workpiece | work 40 along ay direction by unwinding and winding-up the workpiece | work 40 of a roll body.

  The processing table 20 can adsorb and fix the workpiece 40. Irradiation of the workpiece 40 with the pulse laser beam 50 is performed in a state where the workpiece 40 is attracted and fixed to the processing table 20. Further, the machining table 20 can move the workpiece 40 along the z direction (the normal direction of the workpiece 40).

  The lens moving mechanism 13a displaces the focus lens 13 along the optical axis direction of the pulse laser beam 50, and allows the pulse laser beam 50 to be incident on the work 40 with a focus regardless of the incident position. It is.

  Light traveling on a path opposite to the pulse laser beam 50 incident on the workpiece 40 is reflected by the dichroic mirror 14 via the galvano scanner 15 and received by the CCD camera 16. Thereby, an image near the incident position of the pulse laser beam 50 can be obtained. Further, the CCD camera 16 can image an arbitrary position on the workpiece 40 via the galvano scanner 15. Data of an image photographed by the CCD camera 16 is transmitted to the control device 17 and used for control of, for example, laser patterning. The focusing of the CCD camera 16 is performed by moving the workpiece 40 in the z direction by the processing table 20. The optical axis of the laser beam emitted from the laser light source 10 coincides with the optical axis of the light incident on the CCD camera 16. Moreover, both coordinate systems are matched by calibration.

  For example, the CCD camera 18 is arranged above the workpiece 40 conveyed by the workpiece conveyance device 30 so that the incident surface of the pulse laser beam 50 of the workpiece 40 can be directly imaged. For example, a processing area (patterning area) of the workpiece 40 is imaged by the CCD camera 18. Data of an image photographed by the CCD camera 18 is transmitted to the control device 17.

  The control device 17 controls the emission of the pulse laser beam 50 by transmitting a trigger signal to the laser light source 10. Further, the lens moving mechanism 13a is displaced to move the focus lens 13 in the optical axis direction of the pulse laser beam 50, thereby adjusting the focal position of the pulse laser beam 50 on the workpiece 40. Further, the focusing of the CCD camera 16 by the suction and release of the work 40 by the processing table 20 and the movement of the processing table 20 along the z direction is controlled. Further, the conveyance of the workpiece 40 by the workpiece conveyance device 30 is controlled. Further, the galvano scanner 15 is operated to scan the pulse laser beam 50 and adjust the image acquisition position of the CCD camera 16. Further, it receives data of images taken by the CCD cameras 16 and 18 and controls laser patterning. Further, for example, the operation of the CCD cameras 16 and 18 can be controlled by transmitting imaging start and end commands to the CCD cameras 16 and 18.

  With reference to FIGS. 2A to 2C, the laser processing method according to the embodiment will be described.

  FIG. 2A is a schematic plan view showing a part of the workpiece 40. The workpiece 40 is taken up and moved in the y direction by the workpiece conveying device 30. A plurality of work areas (patterning areas) are defined in the length direction (winding direction) of the workpiece 40. In this figure, patterning areas adjacent in the y direction are shown as a patterning area 40a1 and a patterning area 40a2.

In each of the patterning areas 40a1 and 40a2, a plurality of primary patterning lines 40b are linear in the length direction of the workpiece 40 (direction parallel to the y direction) and in the direction perpendicular to the direction (direction parallel to the x direction). Is formed. The number of primary patterning lines 40b formed along the length direction of the workpiece 40 is, for example, 50, and the number of primary patterning lines 40b formed along the direction orthogonal to the length direction is, for example, five. The coordinates of these primary patterning lines 40b are given by, for example, CAD data. Note that the points S _{1 to} S ₅ shown in the drawing are examples of intersections of the primary patterning line 40b extending in the x direction and the primary patterning line 40b extending in the y direction in the patterning area 40a1. Points T _{1 to} T ₅ show examples in the patterning area 40a2.

  The pulse laser beam 50 emitted from the laser light source 10 is irradiated onto the primary patterning line 40b, and Ag film removal processing (patterning processing) is performed so as to trace the primary patterning line 40b.

  The patterning process is performed by transporting the patterning area 40a1 to the suction position of the processing table 20 by the work transporting device 30, attracting and fixing the patterning area 40a1 on the processing table 20, and then making the pulse laser beam 50 enter the patterning area 40a1. When the patterning process of the patterning area 40a1 is completed, the suction of the processing table 20 is released, and the pattern transport area 30 moves the patterning area 40a2 to the suction position of the processing table 20. Thereafter, the patterning area 40a2 is sucked and fixed on the processing table 20, and the pulsed laser beam 50 is incident on the patterning area 40a2 to perform laser patterning. For example, the suction position of the processing table 20 is a region where the pulse laser beam 50 can be incident.

  In the laser processing method according to the embodiment, after the processing of the patterning area 40a1 is completed, the position of the processing mark in the patterning area 40a1 is photographed by the CCD camera 18 while the patterning area 40a2 is moved to the processing position. The photographed image information of the patterning area 40a1 is transmitted to the control device 17. The control device 17 controls the processing of the patterning area 40a2 in consideration of the position of the processing trace of the imaged patterning area 40a1.

FIG. 2B shows an image of the patterning area 40a1 photographed by the CCD camera 18. In the patterning area 40a1, the patterning process for irradiating the pulsed laser beam 50 onto the primary patterning line 40b to form a linear secondary patterning line (processing trace) 40c is completed. The controller 17 analyzes the image transmitted from the CCD camera 18, obtains the center position _{x 1} in the x direction, for example, first primary patterning lines 40b. Next, also secondary patterning lines (processing marks) 40c, obtains the center position _{x 2} in the x direction. Then, the difference Δx = x ₂ −x ₁ between them is calculated. The positional deviation Δx is caused by, for example, a deviation between the laser coordinate system and the CCD camera coordinate system. The absolute value of the positional deviation Δx is preferably small and most preferably zero. In processing the patterning area 40a2, the target incidence of the pulsed laser beam 50 is taken into account by taking into account the positional deviation Δx in the patterning area 40a1, that is, the relative positional relationship between the primary patterning line 40b and the secondary patterning line (processing trace) 40c. Calculate the position.

  Reference is made to FIG. In the processing of the patterning area 40a2, first, from the CAD data, the coordinates of the end points of the primary patterning line 40b in the patterning area 40a2, the primary patterning line 40b extending in the x direction, and the primary patterning line extending in the y direction. The coordinates of a plurality of intersections with 40b are obtained. Next, the galvano scanner 15 is operated, the CCD camera 16 picks up the end points and intersections and performs image processing to perform measurement, finds the deviation, and obtains the actual end points and intersection coordinates. In this case, since the primary patterning line 40b has a width, for example, the representative point of the intersecting area is adopted as the coordinate of the intersection, and the coordinate of the center point is adopted as an example. Then, the position coordinates of the line segment connecting the actual end points and intersections obtained by measurement are calculated, and the target incident position (processing target line) is calculated by adding the positional deviation Δx in the patterning area 40a1 to this.

For example, the processing of the captured image of the operation and the CCD camera 16 of the galvano scanner 15, the coordinates of the intersection point _{T 1} is (50, 100), if the coordinate intersection _{T 2} has been determined to be (50, 90), first The position coordinates of the line segment T ₁ T ₂ are calculated as x = 50 (90 ≦ y ≦ 100). Here, assuming that the positional deviation Δx is +5, for example, the processing target line of the pulse laser beam 50 between the line segments T ₁ T ₂ is corrected to x = 45 (90 ≦ y ≦ 100). The point on this processing target line is set as the target incident position. Then, the galvano scanner 15 is controlled to irradiate the pulse laser beam 50 toward the target incident position (processing target line) to form the secondary patterning line 40c on the primary patterning line 40b in the patterning area 40a2. Processing. Laser patterning between the intersections T ₂ T _{3 and the} like is performed in the same manner.

  According to the laser processing method according to the embodiment, since the processing of the patterning area 40a2 is performed in consideration of the processing trace of the patterning area 40a1 that has already been processed, the processing position accuracy of the patterning area 40a2 is reduced. Can be increased. Therefore, high quality laser processing can be realized.

  In the embodiment, when the patterning area 40a2 is processed, the target incident position information is corrected based on the image information indicating the position of the processing mark of the patterning area 40a1 processed immediately before. There is no need to be based on image information of the processed patterning area. It may be based on the image information of the area processed twice or three times before, or may be corrected by taking the average of the positional deviations based on the image information of the processing area three times before immediately before, for example. Good. Acquisition of image information may or may not be performed every time the patterning area is moved.

Further, positional deviation of working mark in the patterning area 40a1, for example to acquire images of the intersection S ₁ to S _5, obtain the position deviation Δx at each intersection can be calculated by taking the average.

The CCD camera 18 that directly images the workpiece 40 without using the galvano scanner 15 can be installed at one or a plurality of positions along the x direction above the workpiece 40. For example, when only one CCD camera 18 is installed, a positional deviation is calculated for one patterning line extending in the y direction in the patterning area 40a1, and the positional deviation amount is calculated in the y direction of the patterning area 40a2. Can be taken into account for all patterning lines extending to. Further, for example, a CCD camera 18 is prepared for each patterning line extending in the y direction, and the positional deviation can be measured for each patterning line. In this case, for example, the positional deviation calculated with respect to the patterning line where the intersection points S _{1 to} S ₅ exist is reflected in the processing of the patterning line where the intersection points T _{1 to} T ₅ exist corresponding to the pattern line.

  Further, the positional deviation is measured for a plurality of patterning lines thinned out in the x direction, the value is used for the corresponding patterning line, and the patterning line corresponding to the thinned patterning line that is not measured is measured on both sides thereof. Patterning can be performed by using a value obtained by interpolating the position deviation measurement value for the line.

    Although the present invention has been described with reference to the embodiments, the present invention is not limited thereto.

  For example, in the examples, an Ag film having a thickness of 100 nm to 300 nm is formed on a polyimide film and a workpiece prepared as a roll body is a processing target, but the processing target is not limited thereto. It may not be a roll body, and a transparent conductive thin film, for example, an ITO (Indium Tin Oxide) film and an amorphous silicon film may be formed in this order in a thickness of 100 nm to 300 nm on a polyimide film. In this case, a laser beam is incident on the primary patterning line to remove the amorphous silicon film.

  In the embodiment, the patterning area 40a2 is processed in consideration of the positional deviation amount in the patterning area 40a1. However, when the positional deviation amount in the patterning area 40a1 exceeds a predetermined reference value, patterning is performed. It is also possible to adopt a configuration in which an alarm is issued that the calibration of the laser coordinate system and the camera 16 coordinate system should be performed again without processing the area 40a2.

    It will be apparent to those skilled in the art that other various modifications, improvements, combinations, and the like can be made.

  It can be suitably used for laser processing in general, particularly laser patterning processing.

DESCRIPTION OF SYMBOLS 10 Laser light source 11 Attenuator 12 Mask 13 Focus lens 13a Lens moving mechanism 14 Dichroic mirror 15 Galvano scanner 16 Camera 17 Control device 18 Camera 20 Processing table 30 Work conveyance device 40 Work 40a, 40a1, 40a2 Patterning area 40b Primary patterning line 40c 2 Next patterning line (processing marks)
50 laser beam

Claims (6)

A laser light source for emitting a laser beam;
A moving device for moving the workpiece into and out of the machining area;
An optical system including an optical deflector that scans the laser beam emitted from the laser light source so that the incident position of the laser beam moves on the processing object moved into the processing region by the moving device;
A first image sensor that images a workpiece to be moved by the moving device;
Based on the relative positional relationship between the processing trace of the processing object photographed by the first image sensor and the pattern formed before the laser beam irradiation, the laser beam emitted from the laser light source is converted into the processing region. A control device for deriving a target incident position representing a position to be incident on the workpiece moved inward and controlling the operation of the optical deflector so that the laser beam is incident on the target incident position. Laser processing equipment.   2. The laser processing apparatus according to claim 1, wherein the first image sensor images a processing object that is moved from the inside of the processing area to the outside by the moving device.   3. The laser processing apparatus according to claim 1, further comprising a second image sensor that captures an image of the processing object moved into the processing area by the moving device via the optical deflector. 4.   The laser processing apparatus according to any one of claims 1 to 3, wherein the moving device moves the unit region of the processing object of the roll body, in which a plurality of unit regions are defined, into and out of the processing region. (A) a step of causing a laser beam to enter the first region to be processed on which a pattern is formed, and processing the first region to be processed;
(B) imaging the first region to be processed processed in the step (a);
(C) Based on the relative positional relationship between the processing trace of the first processing region imaged in the step (b) and the pattern, a second laser beam different from the first processing region is used. Deriving a target incident position that represents a position to be incident on the workpiece region;
(D) a laser processing method including a step of scanning a laser beam so as to be incident on the target incident position derived in the step (c) and causing the laser beam to enter the second processing region.   6. The laser processing method according to claim 5, wherein, in the step (b), the first processing area is imaged and the second processing area is moved to a laser beam incident area.

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