Laser processing device and laser processing method

Abstract

Provided are a laser processing device and a laser processing method that are capable of accurately emitting laser light to a target position so as to perform processing on an object. Specifically, the present invention comprises: a laser light emission unit 10 that emits laser light L toward a wiring pattern 2; a visible light camera 30 that acquires a visible light image 60v by imaging a glass substrate 60 which is used to adjust the laser light L irradiation position; an IR camera 20 that acquires a laser light image 70i by imaging the laser light L which is emitted from the laser light emission unit 10 and that acquires an infrared light image 60i by imaging infrared light with which the glass substrate 60 is irradiated; and a control unit 80 that adjusts the relative positions of the laser light L irradiation position and the wiring pattern 2 on the basis of the visible light image 60v, the infrared light image 60i, and the laser light image 70i so that the wiring pattern 2 is irradiated with the laser light L, and that controls laser processing on the wiring pattern 2.

Description

Laser processing device and laser processing method

[0001] 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 that adjust the irradiation position of laser light based on a visible light image.

[0002] 2. Description of the Related Art Conventionally, a laser processing apparatus and a laser processing method are known that adjust the irradiation position of laser light based on a visible light image (see, for example, Patent Document 1).

[0003] Patent Document 1 discloses a laser processing apparatus that forms a processed groove on a wafer by irradiating the wafer with laser light along a street, which is a target position for processing. Patent Document 1 uses UV (ultraviolet light) with a wavelength of 400 nm or less, outside the visible light range, as the laser used for processing. The laser processing apparatus of Patent Document 1 also performs alignment detection, in which an image of the wafer is captured with a digital camera and the position of the street, which is the target position, is detected based on the captured visible light observation image. The laser processing apparatus of Patent Document 1 then uses the alignment detection result obtained based on the visible light observation image to align the optical axis of a condenser lens with one end of the street to be processed, thereby aligning the processing position where the laser light is irradiated.

[0004] Japanese Patent Application Laid-Open No. 2022-17863

[0005] As described above, Patent Document 1 discloses a configuration for aligning a processing position where laser light is irradiated by aligning the optical axis of a condenser lens with one end of a street on a workpiece using alignment detection results obtained based on a visible light observation image. However, the irradiation position of the laser irradiation light may change over time and due to changes in ambient temperature, which may cause the actual irradiation position of the laser light to deviate from the target irradiation position. In this case, if a laser processing device aligns the processing position by laser light irradiation using alignment detection results obtained based on a visible light observation image, as in Patent Document 1, it is considered that it cannot detect changes in the irradiation position of laser light, such as infrared laser light, which is not visible in the visible light image. Therefore, if alignment is performed without taking into account changes in the irradiation position of the laser light, the laser light may not be irradiated at the target irradiation position, particularly when the workpiece is very small, resulting in insufficient processing of the workpiece. Therefore, a laser processing device and a laser processing method are desired that can accurately irradiate infrared laser light at the target position to process the workpiece.

[0006] The present invention has been made to solve the above-mentioned problems, and one object of the present invention is to provide a laser processing apparatus and a laser processing method that are capable of processing an object by irradiating an infrared laser beam onto a target position with high precision.

[0007] In order to achieve the above object, a laser processing apparatus according to a first aspect of the present invention comprises a laser light irradiation unit that irradiates an infrared laser light toward an object, a visible light imaging unit that images a position confirmation board for adjusting the irradiation position of the infrared laser light to obtain a visible light image, an infrared light imaging unit that obtains a laser light image by imaging the infrared laser light irradiated from the laser light irradiation unit and obtains an infrared light image by imaging the infrared light irradiated onto the position confirmation board, and a control unit that adjusts the relative position of the infrared laser light irradiation position and the object based on the visible light image, infrared light image, and laser light image so that the object is irradiated with infrared laser light, thereby controlling laser processing of the object.

[0008] As described above, the laser processing apparatus according to the first aspect of the present invention includes a control unit that controls laser processing of the object by adjusting the relative position of the infrared laser light irradiation position and the object based on the visible light image, the infrared light image, and the laser light image so that the object is irradiated with infrared laser light. This makes it possible to compare the positional relationships between the part that appears in the visible light image, the part that appears in the infrared light image, and the infrared laser light irradiation position that appears in the laser light image but not in the visible light image, and adjust the relative position of the infrared laser light irradiation position and the object so that the object is irradiated with infrared laser light. As a result, the infrared laser light can be accurately irradiated at the target position to process the object.

[0009] The laser processing apparatus according to the first aspect preferably further includes an infrared illuminator that irradiates the position confirmation board with infrared light when acquiring the infrared image. With this configuration, the infrared image can be easily generated by capturing an image of the infrared light reflected by or transmitted through the position confirmation board.

[0010] In the laser processing apparatus according to the first aspect, the control unit is preferably configured to acquire a first positional relationship between a target irradiation position of the infrared laser light and an actual irradiation position of the infrared laser light based on a reference position set in the laser light image and the infrared laser light shown in the laser light image, and to adjust the irradiation position of the infrared laser light based on the acquired first positional relationship so that the infrared laser light is irradiated onto the object. With this configuration, the infrared laser light can be appropriately irradiated onto the object at the target position using the first positional relationship between the target irradiation position of the infrared laser light and the actual irradiation position of the infrared laser light.

[0011] In this case, preferably, the position confirmation board includes a position confirmation mark, and the control unit is configured to acquire a second positional relationship between the imaging area of ​​the visible light imaging unit and the imaging area of ​​the infrared light imaging unit based on the mark appearing in the visible light image and the mark appearing in the infrared light image, and to adjust the irradiation position of the infrared laser light so that the infrared laser light is irradiated onto the object based on the acquired first positional relationship and second positional relationship. With this configuration, even when the position of the object to be laser processed is confirmed with the visible light imaging unit before laser irradiation, the positional relationship between the imaging area of ​​the visible light imaging unit and the imaging area of ​​the infrared light imaging unit is known, so that the relative position of the irradiation position of the infrared laser light and the object can be appropriately adjusted.

[0012] In the laser processing apparatus according to the first aspect, the control unit is preferably configured to acquire corrected processing position information obtained by correcting processing position information set for processing the object based on the first positional relationship and the second positional relationship, and to adjust the irradiation position of the infrared laser light so that the object is irradiated with the infrared laser light based on the acquired corrected processing position information. With this configuration, corrected processing position information can be acquired by correcting the processing position information set for processing the object based on the laser light irradiation position, the imaging area of ​​the infrared light imaging unit, and the imaging area of ​​the visible light imaging unit. As a result, even if the laser light irradiation unit fails to irradiate the laser light at the target position or if the images acquired by the infrared light imaging unit and the visible light imaging unit are misaligned with the set imaging areas, the infrared laser light can be appropriately irradiated onto the object at the target position based on the corrected processing position information.

[0013] The laser processing apparatus according to the first aspect preferably further includes a stage on which the object and the position confirmation board are placed and which moves the positions of the infrared light imaging unit and the position confirmation board relative to one another, and the control unit controls the stage to move so that the position confirmation board is positioned at a position where it can be imaged by the infrared light imaging unit when acquiring an infrared image, and to move the stage to move so that the position confirmation board is positioned at a position where it can be imaged by the visible light imaging unit when acquiring a visible light image. With this configuration, since the position confirmation board is also placed on the stage on which the object is placed, correction processing for position adjustment and laser processing of the object can be performed smoothly.

[0014] In this case, preferably, the stage further includes a reflecting mirror that reflects the infrared laser light, and when acquiring the laser light image, the control unit controls the movement of the stage so that the reflecting mirror is positioned at a position where it can be imaged by the infrared light imaging unit. With this configuration, in addition to the object, a reflecting mirror for checking the laser light irradiation position is also positioned on the stage on which the object is placed, so that the correction process for position adjustment using the laser light and the laser processing of the object can be performed more smoothly.

[0015] In the laser processing apparatus having the stage, preferably, the control unit controls the visible light imaging unit to capture an image of the position confirmation board without moving the stage to change the relative positions of the position confirmation board and the infrared imaging unit when acquiring the infrared image. With this configuration, the positions of the object imaged by the infrared imaging unit and the visible light imaging unit do not move, so the positional relationship between the imaging areas of the infrared image and the visible light image can be accurately acquired. As a result, the processing position information set for processing the object can be more accurately corrected.

[0016] In this case, the control unit preferably controls the laser light irradiating unit to irradiate the reflecting mirror with infrared laser light at a lower output than when irradiating the target with infrared laser light. With this configuration, it is possible to perform correction processing to adjust the relative position between the irradiation position of the infrared laser light and the target while suppressing deterioration of the reflecting mirror, compared to when correction processing is performed to adjust the irradiation position of the infrared laser light using infrared laser light with a high output.

[0017] The laser processing apparatus according to the first aspect preferably further includes an alignment camera that captures an image of the object to confirm the processing position on the object, and the alignment camera also serves as a visible light image capture unit. With this configuration, it is possible to obtain a visible light image for adjusting the relative position between the infrared laser light irradiation position and the object using the alignment camera for confirming the processing position, without providing a separate camera for adjusting the infrared laser light irradiation position. As a result, the apparatus can be made smaller.

[0018] In the laser processing device that adjusts the irradiation position of the infrared laser light based on the above-mentioned first positional relationship and second positional relationship, preferably, the position confirmation substrate is a glass substrate, and the mark includes a metal vapor deposition layer applied to the surface of the glass substrate. With this configuration, the mark on the metal vapor deposition layer applied to the surface of the glass substrate has a clearer boundary between the mark and the non-mark portion than a mark applied to the surface using, for example, an oil-based pen, so the positional relationship between the infrared light image and the visible light image can be obtained more accurately. As a result, the processing position information set for processing the target object can be more accurately corrected.

[0019] The laser processing method according to this second aspect includes a laser light image acquisition step of acquiring a laser light image by imaging the infrared laser light irradiated from the laser light irradiation unit, a visible light image acquisition step of acquiring a visible light image by imaging a position confirmation board used to adjust the irradiation position of the infrared laser light, an infrared light image acquisition step of acquiring an infrared light image by imaging the infrared light irradiated onto the position confirmation board, an adjustment step of adjusting the relative position of the irradiation position of the infrared laser light and the object based on the visible light image, the infrared light image, and the laser light image so that the object is irradiated with infrared laser light, and a processing step of processing the object by irradiating it with infrared laser light.

[0020] As described above, the laser processing method according to the second aspect includes an adjusting step of adjusting the relative position of the infrared laser light irradiation position and the object based on the visible light image, the infrared light image, and the laser light image so that the infrared laser light is irradiated onto the object, and a processing step of processing the object by irradiating the infrared laser light. This makes it possible to compare the positional relationships between a portion appearing in the visible light image, a portion appearing in the infrared light image, and the infrared laser light irradiation position that appears in the laser light image but not in the visible light image, and adjust the relative position of the infrared laser light irradiation position and the object so that the infrared laser light is irradiated onto the object. As a result, the laser light can be accurately irradiated onto the target position to process the object.

[0021] According to the present invention, as described above, it is possible to provide a laser processing apparatus and a laser processing method that are capable of processing an object by irradiating a laser beam onto a target position with high precision.

[0022] FIG. 1 is a diagram showing a configuration of a laser processing apparatus according to an embodiment; FIG. 2 is a diagram for explaining an object on a wafer according to an embodiment; FIG. 3 is a flowchart showing a process of a laser processing method according to an embodiment; FIG. 4 is a diagram for explaining an image of a reflecting mirror captured by an IR camera according to an embodiment; FIG. 5 is a diagram for explaining an image of a glass substrate captured by an alignment camera according to an embodiment; and FIG. 6 is a diagram for explaining an image of a glass substrate captured by an IR camera according to an embodiment.

[0023] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0024] The configuration of a laser processing apparatus 100 according to this embodiment will be described with reference to FIG.

[0025] (Configuration of Laser Processing Apparatus) As shown in Fig. 1, the laser processing apparatus 100 includes a laser light irradiation unit 10, a mirror 11, a visible light camera 30, a mirror 21, an IR camera 20, a mirror 31, a visible light illuminator 40, a mirror 41, an infrared light illuminator 42, a stage 50, a moving mechanism 51, a glass substrate 60, a reflecting mirror 70, and a control unit 80. In the drawing, the left-right direction of the laser processing apparatus 100 (one direction in a horizontal plane) is defined as the X direction. The up-down direction (vertical direction) of the laser processing apparatus 100 is defined as the Z direction. The direction perpendicular to the X direction and Z direction of the laser processing apparatus 100 (the other direction in a horizontal plane) is defined as the Y direction.

[0026] The laser light irradiation unit 10 is a light source that emits laser light L with a near-infrared wavelength, for example, a wavelength of 780 nm or more and less than 2500 nm, and is configured to irradiate the laser light L onto the wiring pattern 2 of the wafer 1, which is the processing target. Note that the laser light L cannot be captured by a visible light imaging system such as a visible light camera 30. The laser light irradiation unit 10 is controlled by the control unit 80 and configured to intermittently emit the laser light L so that the irradiation time intervals are uniform. The spot diameter of the laser light L emitted from the laser light irradiation unit 10 when irradiated onto the wiring pattern 2, which is the processing target, is, for example, 3 μm. The laser light L is an example of "infrared laser light" in the claims.

[0027] The mirror 11 is, for example, a half mirror capable of reflecting and transmitting light of infrared wavelengths, and has the function of reflecting part of the laser light L and transmitting part of it. The mirror 11 is also positioned so as to be able to reflect the laser light L so as to change the traveling direction of the laser light L by 90°. As a result, the laser light L emitted from the laser light emitting unit 10 in the X2 direction is reflected by the mirror 11 and irradiated in the Z2 direction. Furthermore, part of the laser light L reflected in the Z1 direction by the reflecting mirror 70 is transmitted through the mirror 11 in the Z1 direction. In this embodiment, the positional relationship and angle between the laser light emitting unit 10 and the mirror 11 are fixed.

[0028] The IR camera 20 is, for example, a digital camera, and includes an internal imaging element (not shown) that is sensitive to light of at least near-infrared wavelengths. This allows the IR camera 20 to capture a laser light image 70i (see FIG. 4) that captures the laser light L irradiating the reflecting mirror 70, and an infrared light image 60i (see FIG. 6) that captures the infrared illumination light irradiating the glass substrate 60. The IR camera 20 is an example of an "infrared light imaging unit" in the claims.

[0029] The mirror 21 is a mirror capable of totally reflecting light with wavelengths in the infrared region. The mirror 21 is positioned so that the infrared light emitted from the infrared light illuminator 42 and the laser light L reflected by the reflecting mirror 70 and the mirror 21 are incident on the IR camera 20. In this embodiment, the positional relationship and angle between the IR camera 20 and the mirror 21 are fixed.

[0030] The visible light camera 30 is, for example, a digital camera, and is capable of capturing magnified images of the wafer 1 and the wiring pattern 2. The visible light camera 30 includes an internal imaging element (not shown) that is sensitive to light of visible wavelengths. The visible light camera 30 is also provided with an infrared filter (not shown) to block laser light L from entering the lens. This allows the visible light camera 30 to capture images of the wafer 1 and the like reflected by the mirror 31, and obtain an image of the wafer 1 and the like, as well as a visible light image 60v (see FIG. 5 ) of the glass substrate 60. The visible light camera 30 is also used to perform alignment detection to confirm the processing position of the wiring pattern 2 to be processed. The visible light camera 30 is an example of a "visible light imaging unit" or "alignment camera" in the claims.

[0031] The mirror 31 is disposed so as to allow reflected light reflected from the wafer 1 or the like to be incident on the visible light camera 30. The mirror 31 is, for example, a dichroic mirror that transmits light in the infrared region and reflects light in the visible region. Therefore, the mirror 31 transmits the laser light L irradiated from the Z1 direction and can reflect the visible light reflected from the Z2 direction so as to change the traveling direction of the reflected light by 90° in the Y direction.

[0032] The visible light illuminator 40 is a lighting device that irradiates light of at least visible wavelengths. The visible light illuminator 40 is configured to continuously irradiate visible light. The mirror 41 is, for example, a dichroic mirror that transmits light with wavelengths in the infrared region and reflects light with wavelengths in the visible region. The mirror 41 is also a half mirror for visible light and has the function of reflecting and transmitting part of the visible light. Therefore, the mirror 41 transmits the laser light L irradiated from the Z1 direction in the Z2 direction, reflects the visible light irradiated from the X1 direction by the visible light illuminator 40 so as to change the traveling direction of the visible light to the Z2 direction, and transmits the reflected visible light reflected from the Z2 direction in the Z1 direction.

[0033] The infrared illuminator 42 is a lighting device that irradiates light of at least a near-infrared wavelength. The infrared illuminator 42 is configured to be able to continuously irradiate infrared light. In this embodiment, the infrared illuminator 42 is attached to the stage 50, for example, by a fastening member (not shown). The infrared illuminator 42 is disposed in the Z2 direction with respect to the glass substrate 60 so as to irradiate infrared light in the Z1 direction. The infrared illuminator 42 is controlled by the control unit 80 and is configured to irradiate infrared light when capturing the infrared light image 60i with the glass substrate 60 disposed in the Z1 direction.

[0034] The stage 50 is capable of placing the wafer 1 on its flat top plate. A glass substrate 60 and a reflecting mirror 70 are fixed to the side of the stage 50 by fastening members (not shown) or the like. The stage 50 also includes a movement mechanism 51, which is configured to be movable at least in the X and Y directions. This allows the movement mechanism 51, controlled by the control unit 80, to move the relative positions of the laser light L and the wafer 1 placed on the top plate of the stage 50.

[0035] The glass substrate 60 is a substrate formed of glass that transmits at least infrared light of near-infrared wavelengths, and is formed of, for example, quartz. The glass substrate 60 also includes a mark 61 centered at the center of gravity of the surface in the Z1 direction. In this embodiment, the mark 61 is formed by metal vapor deposition so that the boundary between the portion with the mark 61 and the portion without the mark 61 is clearly visible. For example, chromium is vapor-deposited as the mark 61. The glass substrate 60 is an example of a "position confirmation substrate" in the claims, and the mark 61 is an example of a "position confirmation mark" in the claims.

[0036] The reflecting mirror 70 is disposed so as to reflect the laser light L incident from the Z1 direction toward the Z2 direction. The reflecting mirror 70 is a replaceable member when deterioration such as burning of the surface occurs due to irradiation with the laser light L, and is replaced after a predetermined irradiation time, a predetermined number of irradiations, or periodically.

[0037] The control unit 80 includes, for example, a processor such as a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and a GPU (Graphics Processing Unit). The control unit 80 is configured to execute a program (software) to perform various controls of the laser light irradiation unit 10, the IR camera 20, the visible light camera 30, the visible light illuminator 40, the infrared light illuminator 42, and the moving mechanism 51 in accordance with a laser processing process flow (see FIG. 3 ) described below. Details of the control performed by the control unit 80 will be described later.

[0038] (Laser Processing Method) Next, a laser processing method in this embodiment for irradiating a target position with laser light L with high precision will be described with reference to Figures 1 to 6. The following description will be given in accordance with the process flow of the laser processing method shown in Figure 3, which is executed by the control unit 80. In this embodiment, the series of steps S1 to S8 described above is performed, for example, every time the wafer 1 to be processed is replaced.

[0039] In this embodiment, as shown in FIG. 2 , which is an enlarged view of the wafer 1 placed on the stage 50, the wafer 1 includes a wiring pattern 2 on its surface. The wiring pattern 2 is, for example, 10 μm wide in the X direction and 1 μm wide in the Y direction, and is an electrically connected pattern. Depending on the circuit configured on the surface of the wafer 1, it may be desirable to cut the wiring pattern 2. In this case, the control unit 80 stores the coordinates of a target point P, which is the center of gravity of the wiring pattern 2, acquired in advance as processing position information for irradiating the wiring pattern 2 with laser light L to perform laser processing to cut the wiring pattern 2. The wafer 1 includes a plurality of wiring patterns 2 (not shown), and the control unit 80 stores the coordinates of all of the plurality of target points P as laser processing position information.

[0040] The control unit 80 executes the following process when the operator inputs a command to start laser processing. First, in a first movement step of step S1, the control unit 80 controls the movement mechanism 51 to move the stage 50 so that the laser light L emitted from the laser light emitting unit 10 is irradiated onto the reflecting mirror 70. At this time, the reflecting mirror 70 is positioned so that the laser light L reflected by the mirror 11 and irradiated in the Z2 direction is irradiated onto the center position (reference position) of the reflecting mirror 70. At this point, the laser light emitting unit 10 is not emitting the laser light L. Then, the process proceeds to step S2.

[0041] Next, in step S2, a laser beam image acquisition process, the control unit 80 acquires a laser beam image 70i and acquires a first positional relationship. Specifically, the control unit 80 first starts irradiating the laser beam L using the laser beam irradiator 10. The irradiation power (output) of the laser beam L in step S2 is approximately 10% of the irradiation power used when actually processing the wiring pattern 2. At this time, the control unit 80 also causes the IR camera 20 to capture an image of the laser beam L reflected on the reflector 70 via the mirror 21, thereby acquiring a laser beam image 70i as shown in FIG. 4 . When the laser beam irradiator 10 irradiates the laser beam L onto the center position of the reflector 70 as set, an irradiation position Lc of the laser beam L is displayed at a center point c1, which indicates the center position of the reflector 70 and is located at the center of the laser beam image 70i captured by the IR camera 20. On the other hand, for example, if the laser light L emitted by the laser light irradiation unit 10 deviates due to ambient temperature or the passage of time, as shown in FIG. 4, the irradiation position Lc of the laser light L shown in the laser light image 70i is at coordinates (xa, ya) with the center point c1 as the reference (0, 0) coordinate. That is, the laser light L is irradiated with a deviation of xa in the X direction and ya in the Y direction from the center point c1, which is the target irradiation position. Note that xa is a negative value and ya is a positive value. At this time, the control unit 80 acquires the coordinates (xa, ya) as the first positional relationship. Thereafter, the process proceeds to step S3.

[0042] As a second movement step of step S3, the control unit 80 controls the movement mechanism 51 to move the stage 50 so that the glass substrate 60 is positioned so that it can be imaged by the visible light camera 30. At this time, the glass substrate 60 is positioned so that the center position as the reference position of the glass substrate 60 coincides with the set center position of the range captured by the image sensor of the visible light camera 30. At this point, the laser light irradiation unit 10 is not emitting laser light L. Then, the process proceeds to step S4.

[0043] In step S4, a visible light image acquisition step, the control unit 80 acquires a visible light image 60v and acquires the position of the mark 61v. Specifically, the control unit 80 first turns on the visible light illuminator 40 and controls the visible light camera 30 to capture an image of the glass substrate 60 and the mark 61 via the mirror 31, thereby acquiring a visible light image 60v in which the glass substrate 60 and the mark 61 are captured. When the visible light camera 30 captures an image at the preset position, the center position of the glass substrate 60 (the center position of the mark 61) is displayed at the center point c2, which is the center position of the visible light image 60v captured by the visible light camera 30. In this embodiment, as shown in FIG. 5 , the center position c3 of the mark 61v captured in the visible light image 60v is located at coordinates (xb, yb) where the center point c2, which is the center position of the visible light image 60v, is used as the reference coordinate (0, 0). That is, the visible light camera 30 captures an image of an area shifted by xb in the X direction and by yb in the Y direction from the set imaging area (imaging field of view). Note that xb and yb are positive values. At this time, the control unit 80 also acquires the coordinates (xb, yb) as visible light mark position information. Then, the process proceeds to step S5.

[0044] In step S5, which is an infrared image acquisition step, the control unit 80 acquires an infrared image 60i and acquires the position of the mark 61i. Specifically, the control unit 80 first controls the IR camera 20 to capture an image of the glass substrate 60 and the mark 61 via the mirror 21, thereby acquiring the infrared image 60i in which the glass substrate 60 and the mark 61 are captured. At this time, the infrared image 60i is acquired without moving the stage 50 from the position of the stage 50 in step S4. If the IR camera 20 captures the image as set, the center position of the glass substrate 60 (the center position of the mark 61) is displayed at the center point c4, which is the center position of the infrared image 60i captured by the IR camera 20. On the other hand, if the installation position of the IR camera 20 is shifted, as shown in FIG. 6 , the center position c5 of the mark 61i captured in the infrared image 60i is at a coordinate (xc, yc) based on the center point c4, which is the center position of the infrared image 60i. That is, the IR camera 20 captures an image of an area shifted by xc in the X direction and yc in the Y direction from the set imaging area. Note that xc is a positive value and yc is a negative value. At this time, the control unit 80 acquires the coordinates (xc, yc) as infrared mark position information. Then, the process proceeds to step S6.

[0045] In the second positional relationship acquisition step of step S6, the control unit 80 acquires a second positional relationship indicating the amount of deviation between the center of the imaging area captured by the visible light camera 30 and the center of the imaging area captured by the IR camera 20, based on the visible light mark position information and the infrared light mark position information. Specifically, based on the coordinates (xb, yb) as the visible light mark position information and the coordinates (xc, yc) as the infrared light mark position information, it is found that the imaging area of ​​the IR camera 20 is shifted by xc-xb in the X direction and by yc-yb in the Y direction relative to the imaging area of ​​the visible light camera 30. At this time, the control unit 80 acquires this amount of deviation as the second positional relationship. Thereafter, the process proceeds to step S7.

[0046] In the processing position information correcting step of step S7, the control unit 80 acquires corrected processing position information by correcting the coordinates of the multiple target points P stored as laser processing position information based on the first positional relationship and the second positional relationship. The control unit 80 acquires the amount of deviation (positional relationship) between the center of the image capture area of ​​the visible light camera 30 and the actual irradiation position Lc of the laser light L by combining the first positional relationship and the second positional relationship. Specifically, the control unit 80 acquires information that the amount of deviation between the center of the image capture area of ​​the visible light camera 30 and the actual irradiation position Lc of the laser light L is xa-(xc-xb) in the X direction and ya-(yc-yb) in the Y direction. As a result, when the coordinates of the target point P stored as laser processing position information are (Px, Py), the control unit 80 acquires the corrected coordinates (Px-(xa+xb-xc), Py-(ya+yb-yc)) as the corrected laser processing position information. If there are multiple pieces of stored laser processing position information, the above correction is performed for each coordinate. This processing position information correction step is an example of the "adjustment step" in the claims. Then, the process proceeds to step S8.

[0047] As the processing step of step S8, the control unit 80 controls the laser light irradiation unit 10 and the moving mechanism 51 to move the stage 50 so that the target point P of the wiring pattern 2 is located at the position of the corrected coordinates (Px-(xa+xb-xc), Py-(ya+yb-yc)) acquired as the corrected laser processing position information, and performs laser processing to cut the wiring pattern 2 by irradiating it with laser light L. This completes the laser processing process.

[0048] (Effects of the embodiment) Next, effects of the embodiment will be described.

[0049] The laser processing apparatus 100 of this embodiment includes a laser light irradiation unit 10 that irradiates laser light L toward the wiring pattern 2, a visible light camera 30 that images the glass substrate 60 to obtain a visible light image 60v in order to adjust the irradiation position Lc of the laser light L, an IR camera 20 that images the laser light L irradiated from the laser light irradiation unit 10 to obtain a laser light image 70i, and an IR camera 20 that images the infrared light irradiated onto the glass substrate 60 to obtain an infrared light image 60i, and a control unit 80 that adjusts the relative position of the irradiation position Lc of the laser light L and the wiring pattern 2 based on the visible light image 60v, the infrared light image 60i, and the laser light image 70i, so that the laser light L is irradiated onto the target point P on the wiring pattern 2, thereby controlling the laser processing of the wiring pattern 2. This makes it possible to compare the positional relationships between the part that appears in the visible light image 60v, the part that appears in the infrared light image 60i, and the irradiation position Lc of the laser light L that appears in the laser light image 70i but does not appear in the visible light image 60v, and to adjust the relative position of the irradiation position Lc of the laser light L and the wiring pattern 2 so that the laser light L is irradiated onto the target point P on the wiring pattern 2. As a result, the laser light L can be accurately irradiated onto the target point P to process the wiring pattern 2.

[0050] In the above embodiment, when acquiring the infrared light image 60i, an infrared light illuminator 42 is further provided which irradiates the glass substrate 60 with infrared light. This makes it possible to easily generate the infrared light image 60i by capturing an image of the infrared light reflected by or transmitted through the glass substrate 60.

[0051] Furthermore, in the above embodiment, the control unit 80 is configured to acquire a first positional relationship between the target irradiation position of the laser light L and the actual irradiation position Lc of the laser light L based on a reference position set in the laser light image 70i and the irradiation position Lc of the laser light L shown in the laser light image 70i, and to adjust the relative position of the irradiation position Lc of the laser light L and the wiring pattern 2 based on the acquired first positional relationship so that the laser light L is irradiated onto the wiring pattern 2. In this way, the laser light L can be appropriately irradiated onto the target point P set on the wiring pattern 2, which is the target position, using the first positional relationship between the target irradiation position of the laser light L and the actual irradiation position Lc of the laser light L.

[0052] Furthermore, in the above embodiment, the glass substrate 60 includes a mark 61, and the control unit 80 is configured to acquire a second positional relationship between the imaging area of ​​the visible light camera 30 and the imaging area of ​​the IR camera 20 based on the mark 61v shown in the visible light image 60v and the mark 61i shown in the infrared light image 60i, and to adjust the relative position of the irradiation position Lc of the laser light L and the wiring pattern 2 based on the acquired first positional relationship and second positional relationship so that the laser light L is irradiated onto the wiring pattern 2. As a result, even when the position of the wiring pattern 2 to be laser processed is confirmed with the visible light camera 30 before laser irradiation, the positional relationship between the imaging area of ​​the visible light camera 30 and the imaging area of ​​the IR camera 20 is known, so that the relative position of the irradiation position Lc of the laser light L and the wiring pattern 2 can be appropriately adjusted.

[0053] In the above embodiment, the control unit 80 is configured to acquire corrected processing position information obtained by correcting processing position information set for processing the wiring pattern 2 based on the first positional relationship and the second positional relationship, and to adjust the irradiation position Lc of the laser light L based on the acquired corrected processing position information so that the laser light L is irradiated onto the wiring pattern 2. This makes it possible to acquire corrected processing position information obtained by correcting the processing position information set for processing the wiring pattern 2 based on the irradiation position Lc of the laser light L, the imaging area of ​​the IR camera 20, and the imaging area of ​​the visible light camera 30. As a result, even when the laser light irradiation unit 10 cannot irradiate the laser light L onto the target position or when the images acquired by the IR camera 20 and the visible light camera 30 are deviated from the set imaging areas, the laser light L can be appropriately irradiated onto the target position, that is, the target point P of the wiring pattern 2, based on the corrected processing position information.

[0054] Furthermore, in the above embodiment, the stage 50 is further provided on which the wiring pattern 2 and the position confirmation substrate are arranged and which moves the positions of the IR camera 20 and the glass substrate 60 relatively, and the control unit 80 controls the stage 50 to move so that the glass substrate 60 is positioned so that it can be imaged by the IR camera 20 when acquiring the infrared light image 60i, and to move the stage 50 to move so that the glass substrate 60 is positioned so that it can be imaged by the visible light camera 30 when acquiring the visible light image 60v. As a result, the glass substrate 60 is also arranged on the stage 50 on which the wafer 1 provided with the wiring pattern 2 is placed, so that correction processing for position adjustment and laser processing of the wiring pattern 2 can be performed smoothly.

[0055] Furthermore, in the above embodiment, the stage 50 further includes a reflecting mirror 70 that reflects the laser light L, and when acquiring the laser light image 70i, the control unit 80 controls the movement of the stage 50 so that the reflecting mirror 70 is positioned so that it can be imaged by the IR camera 20. As a result, the stage 50 on which the wafer 1 provided with the wiring pattern 2 is placed is provided with not only the wafer 1 provided with the wiring pattern 2, but also the reflecting mirror 70 for checking the irradiation position Lc of the laser light L, so that the correction process for position adjustment using the laser light L and the laser processing of the wiring pattern 2 can be performed more smoothly.

[0056] Furthermore, in the above embodiment, the control unit 80 controls the visible light camera 30 to capture an image of the glass substrate 60 without moving the relative positions of the glass substrate 60 and the IR camera 20 using the stage 50 when capturing the infrared light image 60i. This prevents the positions of the wiring pattern 2 captured by the IR camera 20 and the visible light camera 30 from moving, making it possible to accurately capture the positional relationship between the imaging regions of the infrared light image 60i and the visible light image 60v. As a result, the processing position information set for processing the wiring pattern 2 can be corrected more accurately.

[0057] Furthermore, in the above embodiment, the control unit 80 controls the laser light irradiation unit 10 to irradiate the reflecting mirror 70 with laser light L at a lower output than when irradiating the wiring pattern 2 with laser light L. This makes it possible to perform correction processing to adjust the relative position between the irradiation position Lc of the laser light L and the wiring pattern 2 while suppressing deterioration of the reflecting mirror 70, compared to when performing correction processing to adjust the irradiation position Lc of the laser light L using laser light L with a high output.

[0058] Furthermore, in the above embodiment, an alignment camera that captures an image of the wiring pattern 2 to confirm the processing position of the wiring pattern 2 is further provided, and the alignment camera also serves as the visible light camera 30. As a result, without providing a separate alignment camera to adjust the irradiation position Lc of the laser light L, the alignment camera for confirming the processing position can be used to acquire a visible light image 60v for adjusting the relative position between the irradiation position Lc of the laser light L and the wiring pattern 2. As a result, the laser processing apparatus 100 can be made smaller.

[0059] In the above embodiment, the substrate for position confirmation is a glass substrate 60, and the mark 61 includes a metal vapor deposition layer applied to the surface of the glass substrate 60. As a result, the metal vapor deposition mark 61 applied to the surface of the glass substrate 60 has a clearer boundary between marked and unmarked portions than marks applied to the surface using, for example, an oil-based pen, and therefore the positional relationship between the infrared light image 60i and the visible light image 60v can be obtained more accurately. As a result, the processing position information set for processing the wiring pattern 2 can be corrected more accurately.

[0060] [Modifications] The embodiments disclosed herein should be considered to be illustrative in all respects and not restrictive. The scope of the present invention is defined by the claims, not by the description of the above-mentioned embodiments, and further includes all modifications (modifications) within the meaning and scope of the claims.

[0061] For example, in the above embodiment, the laser processing apparatus 100 further includes the infrared illuminator 42 that irradiates the glass substrate 60 with infrared light when acquiring the infrared light image 60i, but the present invention is not limited to this. In the present invention, for example, the infrared illuminator 42 may be attached to a device separate from the laser processing apparatus 100.

[0062] In the above embodiment, the control unit 80 acquires a first positional relationship between the target irradiation position of the laser light L and the actual irradiation position Lc of the laser light L based on the center point c1, which is a reference position set at the center of the laser light image 70i, and the irradiation position Lc of the laser light L shown in the laser light image 70i, and adjusts the relative position of the irradiation position Lc of the laser light L and the wiring pattern 2 based on the acquired first positional relationship so that the laser light L is irradiated onto the wiring pattern 2. However, the present invention is not limited to this. In the present invention, the reference position set in the laser light image 70i does not have to be the center point c1, and the reference position may be set anywhere as long as the coordinates can be identified.

[0063] In the above embodiment, the glass substrate 60 includes the mark 61, which is a mark for confirming position, and the control unit 80 acquires the second positional relationship between the imaging area of ​​the visible light camera 30 and the imaging area of ​​the IR camera 20 based on the mark appearing in the visible light image 60v and the mark 61 appearing in the infrared light image 60i, and adjusts the relative position between the irradiation position Lc of the laser light L and the wiring pattern 2 based on the acquired first positional relationship and second positional relationship so that the laser light L is irradiated onto the wiring pattern 2. However, the present invention is not limited to this. In the present invention, for example, the second positional relationship may be acquired using an edge portion of the glass substrate 60 that does not include the mark 61 as a substitute for the mark.

[0064] In the above embodiment, the control unit 80 acquires corrected processing position information obtained by correcting the processing position information set for processing the wiring pattern 2 based on the first positional relationship and the second positional relationship, and adjusts the relative position between the irradiation position Lc of the laser light L and the wiring pattern 2 based on the acquired corrected processing position information so that the laser light L is irradiated onto the wiring pattern 2. However, the present invention is not limited to this. In the present invention, for example, in a case where processing is performed at a position confirmed in the visible light image 60v without setting processing position information, such as when there are only a few processing locations, the corrected processing position information may not be acquired, and the laser light L may be irradiated at a position adjusted to correspond to the positional relationship acquired by confirming the visible light image 60v.

[0065] Furthermore, in the above embodiment, an example has been shown in which the stage 50 on which the wiring pattern 2 and the glass substrate 60 are arranged and which moves the positions of the IR camera 20 and the glass substrate 60 relative to each other is further provided, and the control unit 80 moves the stage 50 so that the glass substrate 60 is positioned so that it can be imaged by the IR camera 20 when acquiring the infrared light image 60i, and moves the stage 50 so that the glass substrate 60 is positioned so that it can be imaged by the visible light camera 30 when acquiring the visible light image 60v, but the present invention is not limited to this. In the present invention, for example, the glass substrate 60 may be provided separately from the stage 50 and may be positioned so that it can be imaged by the IR camera 20 or the visible light camera 30 when acquiring each of the infrared light image 60i and the visible light image 60v.

[0066] In the above embodiment, a reflecting mirror 70 that reflects the laser light L is further provided, and when acquiring the laser light image 70i, the control unit 80 controls the movement of the stage 50 so that the reflecting mirror 70 is positioned so that it can be imaged by the IR camera 20. However, the present invention is not limited to this. In the present invention, for example, the reflecting mirror 70 may be provided separately from the stage 50, and may be positioned so that it can be imaged by the IR camera 20 when acquiring the laser light image 70i.

[0067] Furthermore, in the above embodiment, an example has been shown in which the control unit 80 controls the visible light camera 30 to capture an image of the glass substrate 60 without moving the relative positions of the glass substrate 60 and the IR camera 20 by using the stage 50 when acquiring the infrared light image 60i, but the present invention is not limited to this. In the present invention, for example, in a case where the optical axes of the light captured by the visible light camera 30 and the IR camera 20 are significantly misaligned and the imaging areas do not overlap well, when acquiring the visible light image 60v, the relative positions of the glass substrate 60 and the IR camera 20 when acquiring the infrared light image 60i may be moved by using the stage 50.

[0068] In the above embodiment, the control unit 80 controls the laser light irradiation unit 10 to irradiate the reflecting mirror 70 with laser light L at a lower output than when irradiating the wiring pattern 2 with laser light L, but the present invention is not limited to this. In the present invention, for example, if the output of the laser light L for processing is originally low, it is not necessary to reduce the output of the laser light L when irradiating the reflecting mirror 70 with laser light L.

[0069] In the above embodiment, an alignment camera is further provided to capture an image of the wiring pattern 2 in order to check the processing position of the wiring pattern 2, and the alignment camera also serves as the visible light camera 30, but the present invention is not limited to this. In the present invention, an imaging device for performing alignment detection may be provided separately from the visible light camera 30.

[0070] In the above embodiment, the glass substrate 60 (position confirmation substrate) is made of a glass material, and the mark 61 includes a metal vapor deposition layer applied to the surface of the glass substrate 60. However, the present invention is not limited to this. In the present invention, the positioning substrate may be made of any material that transmits infrared light. The mark 61 may be made of any material and by any method, as long as the boundary between the portion with the mark 61 and the portion without the mark 61 is clearly visible. For example, a metal other than chromium may be used, or the mark 61 may be formed by sputtering. The size and shape of the glass substrate 60 and the mark 61 may be any size and shape that can be captured by the visible light camera 30 and the IR camera 20.

[0071] In the above embodiment, an example has been shown in which the processing position information for the wiring pattern 2 provided on the wafer 1 is corrected every time the wafer 1 is replaced, but the present invention is not limited to this. In the present invention, the processing position information may be corrected at any timing, for example, every predetermined time or every time the control unit 80 is started. In addition, the processing target is not limited to the wiring pattern 2 provided on the wafer 1, and may be any material that can be melted by the energy of the laser light L.

[0072] In the above embodiment, the position of the laser light emitting unit 10 is fixed, and the position of the stage 50 is changed by the moving mechanism 51 to change the irradiation position Lc of the laser light L. However, the present invention is not limited to this. For example, the present invention may be configured such that a galvanometer control system consisting of a galvanometer mirror and an fθ lens is provided on the optical axis of the laser light L emitted from the laser light emitting unit 10, and the irradiation position Lc of the laser light L is changed by changing the orientation (angle) of the galvanometer mirror.

[0073] In the above embodiment, the laser light L emitted from the laser light irradiating unit 10 and the infrared light emitted from the infrared light illuminator 42 are near-infrared light, but the present invention is not limited to this. In the present invention, the laser light L emitted from the laser light irradiating unit 10 and the infrared light emitted from the infrared light illuminator 42 may be mid-infrared light with a wavelength of 2500 nm or more and less than 4000 nm. In addition, the wavelength of the laser light L emitted from the laser light irradiating unit 10 and the wavelength of the infrared light emitted from the infrared light illuminator 42 may be different.

[0074] In the above embodiment, the infrared illuminator 42 is provided in the Z2 direction relative to the glass substrate 60 and is arranged to irradiate infrared light in the Z1 direction, but the present invention is not limited to this. In the present invention, the infrared illuminator 42 may be provided in the Z1 direction relative to the glass substrate 60 and is arranged to irradiate infrared light in the Z2 direction.

[0075] In the above embodiment, the infrared light illuminator 42, the glass substrate 60, and the reflecting mirror 70 are fixed to the stage 50, but the present invention is not limited to this. In the present invention, the infrared light illuminator 42, the glass substrate 60, and the reflecting mirror 70 may each be provided on a support member (not shown) or the like that is provided separately from the stage 50.

[0076] REFERENCE SIGNS LIST 1 Wafer 2 Wiring pattern (object) 10 Laser light irradiation unit 20 IR camera (infrared light imaging unit) 30 Visible light camera (visible light imaging unit, alignment camera) 42 Infrared light illumination 50 Stage 60 Glass substrate (substrate for position confirmation) 60i Infrared light image 60v Visible light image 61 Mark (mark for position confirmation) 61i Mark (mark shown in infrared light image) 61v Mark (mark shown in visible light image) 70 Reflecting mirror 70i Laser light image 80 Control unit L Laser light Lc Laser light irradiation position P Target point

Claims

1. A laser processing device comprising: a laser light irradiation unit that irradiates an infrared laser light toward an object; a visible light imaging unit that acquires a visible light image by imaging a position confirmation board for adjusting the irradiation position of the infrared laser light; an infrared light imaging unit that acquires a laser light image by imaging the infrared laser light irradiated from the laser light irradiation unit, and acquires an infrared light image by imaging the infrared light irradiated onto the position confirmation board; and a control unit that adjusts the relative position of the infrared laser light irradiation position and the object based on the visible light image, the infrared light image, and the laser light image, so that the infrared laser light is irradiated onto the object, thereby controlling laser processing of the object.

2. The laser processing device according to claim 1, further comprising an infrared light illuminator that irradiates the position confirmation board with the infrared light when acquiring the infrared light image.

3. The laser processing device of claim 1, wherein the control unit is configured to acquire a first positional relationship between the target irradiation position of the infrared laser light and the actual irradiation position of the infrared laser light based on a reference position set in the laser light image and the infrared laser light reflected in the laser light image, and to adjust the relative position of the irradiation position of the infrared laser light and the object based on the acquired first positional relationship so that the infrared laser light is irradiated onto the object.

4. The laser processing device of claim 3, wherein the position confirmation board includes a position confirmation mark, and the control unit is configured to acquire a second positional relationship between the imaging area of ​​the visible light imaging unit and the imaging area of ​​the infrared light imaging unit based on the mark that appears in the visible light image and the mark that appears in the infrared light image, and to adjust the relative position of the irradiation position of the infrared laser light and the object based on the acquired first positional relationship and second positional relationship so that the infrared laser light is irradiated onto the object.

5. The laser processing device of claim 4, wherein the control unit is configured to acquire corrected processing position information obtained by correcting processing position information set for processing the object based on the first positional relationship and the second positional relationship, and to adjust the relative position of the irradiation position of the infrared laser light and the object based on the acquired corrected processing position information so that the infrared laser light is irradiated onto the object.

6. A laser processing device as described in claim 1, further comprising a stage on which the object and the position confirmation board are placed and which moves the positions of the infrared light imaging unit and the position confirmation board relatively, wherein the control unit controls to move the stage so that the position confirmation board is positioned at a position where it can be imaged by the infrared light imaging unit when acquiring the infrared light image, and to move the stage so that the position confirmation board is positioned at a position where it can be imaged by the visible light imaging unit when acquiring the visible light image.

7. The laser processing device according to claim 6, wherein the stage further includes a reflecting mirror that reflects the infrared laser light, and the control unit controls the movement of the stage so that, when acquiring the laser light image, the reflecting mirror is positioned at a position where it can be imaged by the infrared light imaging unit.

8. A laser processing device as described in claim 6, wherein the control unit controls the visible light imaging unit to image the position confirmation board without moving the relative positions of the position confirmation board and the infrared light imaging unit using the stage when acquiring the infrared light image.

9. A laser processing device as described in claim 7, wherein the control unit controls the laser light irradiation unit so that when irradiating the infrared laser light onto the reflecting mirror, the output is smaller than when irradiating the infrared laser light onto the object.

10. The laser processing device according to claim 1, further comprising an alignment camera that takes an image of the object to confirm the processing position of the object, the alignment camera also serving as the visible light imaging unit.

11. The laser processing device according to claim 4, wherein the position confirmation substrate is a glass substrate, and the mark includes a metal deposition layer applied to the surface of the glass substrate.

12. A laser processing method comprising: a laser light image acquisition step of acquiring a laser light image by capturing an image of infrared laser light irradiated from a laser light irradiation unit; a visible light image acquisition step of acquiring a visible light image by capturing an image of a position confirmation board used to adjust the irradiation position of the infrared laser light; an infrared light image acquisition step of acquiring an infrared light image by capturing an image of infrared light irradiated onto the position confirmation board; an adjustment step of adjusting the relative position of the irradiation position of the infrared laser light and the object based on the visible light image, the infrared light image, and the laser light image so that the object is irradiated with the infrared laser light; and a processing step of processing the object by irradiating the infrared laser light.

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