Laser processing device and laser processing method

Abstract

To provide a laser processing device and a laser processing method which can process a work-piece while accurately emitting laser light other than visible light to a target position.SOLUTION: A laser processing device 100 performs processing of a wiring pattern 2 using laser light while adjusting an emission position for laser light L so that the laser light L is emitted to a processing position P for the wiring pattern 2, on the basis of a laser light image 80, photographed with a common wide-area camera 20, which is a photographed image of the laser light L constituted of non-visible light other than visible light and a work-piece image 70 that is a photographed image of the wiring pattern 2 by imaging visible light.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[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 by image processing. [Background technology]

[0002] BACKGROUND ART Conventionally, a laser processing apparatus and a laser processing method are known that adjust the irradiation position of laser light by image processing (see, for example, Patent Document 1).

[0003] The above-mentioned Patent Document 1 discloses a laser processing device that forms processing grooves on a wafer by irradiating the wafer with laser light along streets that divide multiple devices into a grid pattern, which are target positions for processing. In the above-mentioned Patent Document 1, UV (ultraviolet light) with a wavelength of 400 nm or less, outside the visible light range, is used as the laser light used for processing. Furthermore, the laser processing device of the above-mentioned Patent Document 1 performs alignment detection by capturing an image of the wafer with a digital camera and detecting the position of the street, which is the target position, based on the captured visible light image, which is an observation image. Then, the laser processing device of the above-mentioned Patent Document 1 uses the alignment detection result obtained based on the observation image, which is a visible light image, to align the processing position to be irradiated with the laser light and perform laser processing. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2022-17863 Summary of the Invention [Problem to be solved by the invention]

[0005] The laser beam irradiation position may change over time and due to influences on the laser beam transmission optical system, such as changes in ambient temperature. However, the laser processing device described in Patent Document 1 cannot detect changes in the irradiation position of non-visible laser beams that are not captured in the visible light image. Therefore, processing may be performed while the target processing position and the actual laser beam irradiation position are misaligned. In the laser processing device described in Patent Document 1, to align the target processing position and the actual laser beam irradiation position, it is necessary to adjust the laser beam irradiation position by comparing an image of the laser beam captured by an imaging device capable of capturing non-visible laser beams, unlike the digital camera, with a visible light image captured by the digital camera. However, because different imaging devices have different fields of view, it may be difficult to accurately adjust the irradiation position of the laser beam actually irradiated on the target processing position. Therefore, a laser processing device and a laser processing method are desired that can accurately irradiate non-visible laser beams on the target position to process a 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 a workpiece by precisely irradiating a laser beam other than visible light onto a target position. [Means for solving the problem]

[0007] In order to achieve the above object, a laser processing apparatus according to a first aspect of the present invention is a laser processing apparatus that performs laser processing by irradiating a workpiece with laser light, and includes a laser light irradiation unit that irradiates laser light composed of invisible light other than visible light, a common imaging unit that images the laser light irradiated from the laser light irradiation unit and images the workpiece by focusing the visible light, and a control unit that controls laser processing of the workpiece by adjusting the irradiation position of the laser light so that the laser light is irradiated at the processing position on the workpiece based on the image of the laser light and workpiece imaged by the common imaging unit.

[0008] In the laser processing apparatus according to the first aspect, as described above, the laser processing of the workpiece is performed by adjusting the irradiation position of the laser light so that the laser light is irradiated at the processing position on the workpiece based on the captured image of the laser light composed of invisible light other than visible light captured by the common imaging unit and the captured image of the workpiece captured by imaging visible light. This makes the fields of view of the imaging unit that captures the laser light other than visible light and the imaging unit that images the workpiece by imaging visible light the same, so the irradiation position of the laser light can be adjusted with high precision. As a result, the laser light other than visible light can be accurately irradiated at the target position to process the workpiece.

[0009] In the laser processing apparatus according to the first aspect, the imaging unit is preferably configured to capture an image of the laser light while irradiating the laser light near the processing position on the workpiece. With this configuration, the processing position on the workpiece and the irradiation position of the laser light can be directly compared to adjust the irradiation position of the laser light, so that the irradiation position of the laser light can be adjusted with higher accuracy. Note that the vicinity of the processing position on the workpiece is a broad concept that includes not only the processing position on the workpiece itself but also the periphery of the processing position on the workpiece.

[0010] In this case, preferably, the control unit controls the laser light irradiating unit so that, when the imaging unit images the laser light irradiated near the processing position on the workpiece, the laser light irradiating unit irradiates the laser light at a lower output than the output of the laser light irradiated during laser processing. With this configuration, it is possible to prevent the workpiece from being processed by the laser light irradiated when the laser light is imaged.

[0011] In the laser processing device that irradiates the laser light at low power when imaging the laser light, preferably, the control unit controls the laser light irradiating unit to irradiate the laser light at low power and as a continuous wave when the imaging unit images the laser light irradiated near the processing position on the workpiece. With this configuration, unlike when imaging pulsed laser light that is intermittently irradiated, the imaging unit can image the laser light even with laser light that is so low power that it does not process the workpiece.

[0012] In the laser processing apparatus according to the first aspect, the control unit is preferably configured to acquire an amount of deviation between the position of the laser beam shown in the image captured by the common imaging unit and the position of the workpiece, and to adjust the irradiation position of the laser beam based on the acquired amount of deviation so that the laser beam is irradiated onto the processing position on the workpiece. With this configuration, the irradiation position of the laser beam and the position of the workpiece can be easily adjusted and matched based on the amount of deviation, so that the irradiation position of the laser beam can be easily adjusted.

[0013] In the laser processing device that images the laser light while irradiating the laser light near the processing position, preferably, the imaging unit is configured to image a positioning mark that is positioned a predetermined distance away from the workpiece, and the control unit is configured to adjust the imaging position of the imaging unit by moving the imaging unit and the workpiece relatively to each other so that the processing position relative to the workpiece is imaged based on the position of the positioning mark imaged by the imaging unit, and to cause the imaging unit to image the laser light and the workpiece. With this configuration, the imaging position of the imaging unit can be easily adjusted compared to when the imaging position of the imaging unit is adjusted so that the processing position relative to the workpiece can be imaged without being based on the position of the positioning mark.

[0014] A laser processing method according to a second aspect of the present invention is a laser processing method for performing laser processing by irradiating a workpiece with laser light, and includes an imaging step in which a common imaging unit images laser light composed of invisible light other than visible light irradiated from the laser light irradiating unit and images the workpiece by focusing the visible light, an adjustment step in which, based on the image of the laser light and workpiece captured in the imaging step, adjusts the irradiation position of the laser light so that the laser light is irradiated at the processing position on the workpiece, and a processing step in which the workpiece is processed by irradiating the laser light.

[0015] In the laser processing method according to the second aspect, as described above, the irradiation position of the laser light is adjusted so that the laser light is irradiated at the processing position on the workpiece based on the captured image of the laser light composed of invisible light other than visible light captured by the common imaging unit and the captured image of the workpiece captured by imaging visible light, thereby performing laser processing of the workpiece. This makes the fields of view of the imaging unit that captures the laser light other than visible light and the imaging unit that images the workpiece by imaging visible light the same, so the irradiation position of the laser light can be adjusted with high precision. As a result, it is possible to provide a laser processing method that can accurately irradiate the laser light other than visible light at the target position to process the workpiece. [Effects of the Invention]

[0016] As described above, the laser processing apparatus and laser processing method of the present invention can process a workpiece by irradiating a target position with laser light other than visible light with high precision. [Brief explanation of the drawings]

[0017] [Figure 1] 1 is a schematic diagram showing the overall configuration of a laser processing apparatus according to an embodiment of the present invention; [Figure 2] FIG. 2 is a top view of a workpiece on a wafer according to one embodiment of the present invention. [Figure 3] 3 is a flowchart illustrating a process of a laser processing method according to an embodiment of the present invention. [Figure 4] FIG. 2 is a plan view showing alignment marks on a wafer according to one embodiment of the present invention. [Figure 5] FIG. 10 is a diagram showing a captured image of an alignment mark according to an embodiment of the present invention. [Figure 6] FIG. 2 is a diagram showing a captured image of a workpiece according to an embodiment of the present invention. [Figure 7] FIG. 10 is a diagram showing a captured image of laser light according to an embodiment of the present invention. [Figure 8] FIG. 10 is a diagram showing a captured image of a workpiece and laser light simultaneously captured according to a modified example of an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0018] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, specific embodiments of the present invention will be described with reference to the accompanying drawings.

[0019] [Embodiment] (Configuration of laser processing equipment) The configuration of a laser processing apparatus 100 according to one embodiment of the present invention will be described with reference to FIGS. 1, 2 and 4. FIG.

[0020] As shown in FIGS. 1 and 2, the laser processing apparatus 100 is an apparatus for irradiating a workpiece on a wafer with laser light to perform processing. For example, the laser processing apparatus 100 is an apparatus for irradiating a processing position P of a wiring pattern 2 on a wafer 1 with laser light L to perform processing. The wiring pattern 2 is, for example, a fuse having a width of 1 μm and a length of 10 μm. Processing may be, for example, blowing the fuse. Processing position P may be, for example, the center of gravity of the wiring pattern 2. The wiring pattern 2 is an example of a "workpiece" in the claims.

[0021] As shown in FIG. 1, the laser processing apparatus 100 includes a laser beam irradiation unit 10, a mirror 11, a wide-area camera 20, a mirror 21, a visible light illuminator 30, a mirror 31, a stage 40, a moving mechanism 41, and a control unit 50. In FIG. 1, 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 and Z directions of the laser processing apparatus 100 (the other direction in a horizontal plane) is defined as the Y direction. In the following description, one side of the X direction is defined as the X1 direction, and the other side is defined as the X2 direction. The back side of the Y direction in FIG. 1 is defined as the Y2 direction, and the front side is defined as the Y1 direction. In the Z direction, the direction of increasing height is defined as the Z1 direction, and the direction of decreasing height is defined as the Z2 direction. The wide-area camera 20 is an example of an "imaging unit" in the claims.

[0022] 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. When processing the wiring pattern 2, the laser light irradiation unit 10 is controlled by the control unit 50 and configured to irradiate the wiring pattern 2 on the wafer 1 with pulsed laser light L. The spot diameter of the laser light L irradiated by the laser light irradiation unit 10 on the wiring pattern 2 is, for example, 3 μm.

[0023] The wide area camera 20 has an internal imaging element (not shown) that is sensitive to at least visible light and the wavelength of the laser light L. The wide area camera 20 is also configured to capture images of the laser light L, the wiring pattern 2, and an alignment mark R (see FIG. 4) described below. The wide area camera 20 is configured to output the captured images to the control unit 50. The wide area camera 20 is, for example, a camera that has an internal SWIR image sensor manufactured by Sony Corporation.

[0024] The visible light illuminator 30 is a lighting device that irradiates visible light. The visible light illuminator 30 is controlled by the control unit 50 and is configured to be able to continuously irradiate visible light.

[0025] The mirror 11 is configured to reflect a portion of the incident laser light L and transmit the remainder. The mirror 11 is also configured to transmit most of the incident visible light. In this embodiment, the mirror 11 reflects a portion of the laser light L irradiated from the laser light irradiation unit 10 toward the wafer 1 side (Z2 direction), and transmits a portion of the laser light L coming from the wafer 1 side toward the mirror 21 side (Z1 direction). The mirror 11 also transmits most of the visible light coming from the wafer 1 side and transmitted through the mirror 31 toward the mirror 21 side (Z1 direction). The mirror 11 is a so-called dichroic mirror.

[0026] The mirror 21 is configured to reflect most of the incident laser light L. The mirror 21 is also configured to reflect most of the incident visible light. In this embodiment, the mirror 21 reflects most of the laser light L that comes from the wafer 1 side and has passed through the mirrors 31 and 11 toward the wide area camera 20 (X1 direction). In this embodiment, the mirror 21 reflects most of the visible light that comes from the wafer 1 side and has passed through the mirrors 31 and 11 toward the wide area camera 20 (X1 direction).

[0027] The mirror 31 is configured to transmit most of the incident laser light L. The mirror 31 is also configured to reflect a portion of the incident visible light and transmit the remainder. In this embodiment, the mirror 31 is configured to transmit most of the laser light L reflected by the mirror 31 toward the wafer 1 side (Z2 direction). In this embodiment, the mirror 31 reflects a portion of the visible light irradiated from the visible light illumination 30 toward the wafer 1 side (Z2 direction), and transmits a portion of the visible light coming from the wafer 1 side toward the mirror 11 side (Z1 direction). The mirror 31 is a so-called dichroic mirror.

[0028] In this embodiment, the positions and angles of the laser light emitting unit 10, wide-area camera 20, visible light illuminator 30, mirror 11, mirror 21, and mirror 31 are fixed in an appropriately adjusted state. In addition, the various light rays incident on the wide-area camera 20 and the laser light L irradiated from the laser light emitting unit 10 are coaxial with the arrangement of the mirrors 11, 21, and 31.

[0029] The stage 40 is capable of placing the wafer 1 on a flat top plate (the surface on the Z1 side). The stage 40 includes a moving mechanism 41. The moving mechanism 41 is configured to be able to move the stage 40 at least in the X and Y directions by being controlled by the control unit 50. As a result, the moving mechanism 41 controlled by the control unit 50 moves the relative position between the laser light L irradiated by the laser light irradiator 10 and the stage 40. The moving mechanism 41 controlled by the control unit 50 also moves the relative position between the visible light irradiated by the visible light illuminator 30 and the stage 40.

[0030] The control unit 50 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 50 is configured to execute a program (software) to perform various controls of the laser light irradiation unit 10, the wide-area camera 20, the visible light illuminator 30, and the moving mechanism 41 in accordance with a laser processing process flow (see FIG. 3) described below. Details of the control performed by the control unit 50 will be described later.

[0031] (Laser processing method) Next, the laser processing method according to the present embodiment will be described with reference to FIGS.

[0032] As shown in FIGS. 3 and 4, in step S1, the control unit 50 (see FIG. 1) moves the stage 40 to a position where the wide-area camera 20 can capture an image of the alignment mark R. Specifically, as shown in FIG. 4, the control unit 50 controls the movement mechanism 41 (see FIG. 1) to move the stage 40 to a position where the wide-area camera 20 can capture an image of the alignment mark R formed on the wafer 1. Here, the control unit 50 stores in advance the approximate position of the alignment mark R. The alignment mark R is composed of, for example, two rectangular marks extending in the left-right direction (X direction) of the drawing and another rectangular mark extending in the up-down direction (Y direction) of the drawing. The alignment mark R is formed on the wafer 1 by, for example, photolithography. The alignment mark R is formed at a position spaced a predetermined distance from the processing position P of the wiring pattern 2 (see FIG. 2), and the control unit 50 stores in advance the positional relationship between the alignment mark R and the processing position P of the wiring pattern 2. The alignment mark R is an example of a "positioning mark" in the claims.

[0033] Returning to FIG. 3, in step S2, the control unit 50 (see FIG. 1) acquires an image and coordinates of the alignment mark R. Specifically, as shown in FIG. 5, the control unit 50 causes the visible light illuminator 30 (see FIG. 1) to emit visible light, and then acquires an alignment mark image 60 captured by the wide-area camera 20 and the coordinates (xa, ya) of the alignment mark R that appear in the alignment mark image 60. Here, the coordinates represent the amount of deviation in the left-right direction (X direction) and the up-down direction (Y direction) in the captured image, based on the coordinates (0, 0) of the center point C1 of the captured image. Note that in the case of deviation in the left-right direction, a positive value is obtained when the image is deviated to the right from the coordinates (0, 0) of the center point C1, and a negative value is obtained when the image is deviated to the left. In addition, in the case of deviation in the up-down direction, a positive value is obtained when the image is deviated upward from the coordinates (0, 0) of the center point C1, and a negative value is obtained when the image is deviated downward from the coordinates (0, 0) of the center point C1. The coordinates of the alignment mark R are obtained with respect to the center RC of the alignment mark R.

[0034] 3, in step S3, the control unit 50 (see FIG. 1) moves the stage 40 to a position where the workpiece can be imaged. Specifically, the control unit 50 controls the movement mechanism 41 (see FIG. 1) to move the stage 40 to a position where the wide-area camera 20 can image the processing position P of the wiring pattern 2, based on the coordinates (xa, ya) of the alignment mark R acquired in step S2 and the positional relationship between the alignment mark R and the processing position P of the wiring pattern 2 (see FIG. 2), which has been stored in advance.

[0035] In step S4, the control unit 50 (see FIG. 1) acquires an image and coordinates of the workpiece. Note that step S4 is started after the completion of step S3. Specifically, as shown in FIG. 6, the control unit 50 causes the visible light illuminator 30 (see FIG. 1) to emit visible light, and then acquires a workpiece image 70 captured by the wide-angle camera 20 while the visible light is being emitted, and the coordinates (xb, yb) of the processing position P of the wiring pattern 2 that appear in the workpiece image 70. Here, in step S3, the processing position P of the wiring pattern 2 is adjusted to coincide with the center point C1 of the captured image. However, due to various errors associated with the movement of the stage 40, the processing position P of the wiring pattern 2 may not coincide with the center point C1 of the captured image, as shown in FIG. 6. Note that in order to accurately acquire the coordinates of the processing position P of the wiring pattern 2, it is preferable that the laser light emitting unit 10 does not irradiate the laser light L during step S4.

[0036] Returning to FIG. 3, in step S5, the control unit 50 (see FIG. 1) starts emitting the laser light L. Note that step S5 starts after the completion of step S3. Specifically, as shown in FIG. 1, the control unit 50 controls the laser light emitting unit 10 to start emitting the laser light L. Here, as described above, the various light beams incident on the wide-area camera 20 and the laser light L irradiated from the laser light emitting unit 10 are coaxial, so that the laser light L irradiated in step S5 is irradiated near the processing position P of the wiring pattern 2. Note that in this embodiment, in order to prevent the wiring pattern 2 (see FIG. 2) from being processed by the laser light L irradiated in step S5, the laser light L irradiated in step S5 is a continuous wave, unlike the pulsed laser light L irradiated when processing the wiring pattern 2. The laser light irradiated unit 10 is configured to be able to switch between irradiating the continuous wave laser light L and the pulsed laser light L.

[0037] Returning to FIG. 3, in step S6, the control unit 50 (see FIG. 1) acquires an image and coordinates of the laser light L. Note that step S6 is started after step S5 is completed. Specifically, as shown in FIG. 7, the control unit 50 acquires a laser light image 80 captured by the wide-area camera 20 while the laser light L is being emitted, and the coordinates (xc, yc) of the laser light L shown in the laser light image 80. Then, after acquiring the laser light image 80 and the coordinates (xc, yc) of the laser light L shown in the laser light image 80, the control unit 50 stops the emission of the laser light L started in step S5. The coordinates of the laser light L are acquired with respect to the irradiation position LC of the laser light L located at the center of the laser light L shown in the laser light image 80. Note that in order to accurately acquire the coordinates of the laser light L, it is preferable that the visible light illuminator 30 not emit visible light during step S6.

[0038] Returning to FIG. 3 , in step S7, the control unit 50 (see FIG. 1 ) adjusts the irradiation position of the laser light L based on the positional relationship between the workpiece and the laser light L. Note that step S7 is started after both steps S4 and S6 are completed. Specifically, as shown in FIGS. 6 and 7 , the control unit 50 calculates the amount of misalignment between the coordinates (xb, yb) of the processing position P of the wiring pattern 2 shown in the workpiece image 70 and the coordinates (xc, yc) of the laser light L shown in the laser light image 80. The amount of misalignment represents the amount of misalignment of the laser light irradiation position with respect to the processing position P of the wiring pattern 2. In this embodiment, the amount of misalignment is calculated as (xc-xb, yc-yb). Then, the control unit 50 controls the moving mechanism 41 to move the stage 40 by the calculated amount of misalignment (xc-xb, yc-yb) to adjust the irradiation position of the laser light L to coincide with the processing position P of the wiring pattern 2.

[0039] Returning to FIG. 3, in step S8, the control unit 50 (see FIG. 1) processes the workpiece. Specifically, the control unit 50 controls the laser light irradiation unit 10 to irradiate the processing position P of the wiring pattern 2 with pulsed laser light L, thereby processing the wiring pattern 2. After step S8 is completed, the procedure of the laser processing method is completed. Note that steps S1 to S8 are performed for each predetermined area in the wafer 1, and more preferably, for each processing position P.

[0040] (Effects of the embodiment) Next, the effects of this embodiment will be described.

[0041] In this embodiment, as described above, based on the laser light image 80, which is an image of the laser light L composed of invisible light other than visible light captured by the common wide-area camera 20, and the workpiece image 70, which is an image of the wiring pattern 2 captured by focusing visible light, the irradiation position of the laser light L is adjusted so that the laser light L is irradiated at the processing position P on the wiring pattern 2, thereby performing laser processing of the wiring pattern 2. This makes the fields of view of the wide-area camera 20 that captures the laser light L other than visible light and the wide-area camera 20 that captures the wiring pattern 2 by focusing visible light the same, so that the irradiation position of the laser light L can be adjusted with high precision. As a result, the laser light L other than visible light can be accurately irradiated at the target position to process the wiring pattern 2.

[0042] Furthermore, in this embodiment, as described above, the wide-area camera 20 is configured to capture an image of the laser light L while the laser light L is irradiated near the processing position P on the wiring pattern 2. This makes it possible to directly compare the processing position P on the wiring pattern 2 with the irradiation position of the laser light L and adjust the irradiation position of the laser light L, thereby making it possible to adjust the irradiation position of the laser light L with higher precision.

[0043] Furthermore, in this embodiment, as described above, the control unit 50 controls the laser light irradiating unit 10 to irradiate the laser light L at a lower output than the output of the laser light L irradiated during laser processing when the wide-area camera 20 captures an image of the laser light L irradiated near the processing position P on the wiring pattern 2. This makes it possible to prevent the wiring pattern 2 from being processed by the laser light L irradiated when the laser light L is captured.

[0044] Furthermore, in this embodiment, as described above, when the wide-area camera 20 captures the laser light L irradiated near the processing position P on the wiring pattern 2, the control unit 50 controls the laser light irradiating unit 10 to irradiate the laser light L at low output and as a continuous wave. This allows the wide-area camera 20 to capture the laser light L even with laser light L of such low output that the wiring pattern 2 is not processed, unlike when capturing an image of pulsed laser light L that is irradiated intermittently.

[0045] Furthermore, in this embodiment, as described above, the control unit 50 is configured to acquire the amount of deviation between the position of the laser light L shown in the image captured by the common wide-area camera 20 and the position of the wiring pattern 2, and adjust the irradiation position of the laser light L based on the acquired amount of deviation so that the laser light L is irradiated onto the processing position P on the wiring pattern 2. This allows the irradiation position of the laser light L to be easily adjusted and matched with the position of the wiring pattern 2 based on the amount of deviation, so that the irradiation position of the laser light L can be easily adjusted.

[0046] Furthermore, in this embodiment, as described above, the wide area camera 20 is configured to capture an image of the alignment mark R located at a predetermined distance from the wiring pattern 2, and the control unit 50 is configured to adjust the imaging position of the wide area camera 20 by relatively moving the wide area camera 20 and the wiring pattern 2 so that the processing position P for the wiring pattern 2 is imaged based on the position of the alignment mark R imaged by the wide area camera 20, and to cause the wide area camera 20 to image the laser light L and the wiring pattern 2. This makes it easier to adjust the imaging position of the wide area camera 20 compared to when the imaging position of the wide area camera 20 is adjusted so that the processing position P for the wiring pattern 2 can be imaged without being based on the position of the alignment mark R.

[0047] [Variations] The embodiments disclosed herein should be considered to be illustrative and not restrictive in all respects. The scope of the present invention is defined by the claims rather than the above description of the embodiments, and further includes all modifications (variations) within the meaning and scope of the claims.

[0048] For example, in this embodiment, an example in which the workpiece is a wiring pattern on a wafer has been shown, but the present invention is not limited to this. For example, the workpiece may be a wiring that is not formed on a wafer, or may be an object made of resin or the like that can be processed by laser light. Furthermore, the wiring pattern may be a simple wiring pattern other than a fuse.

[0049] In addition, in this embodiment, the laser light L is a near-infrared ray, but the present invention is not limited to this. For example, the laser light L may be an ultraviolet ray.

[0050] In addition, in the present embodiment, an example has been shown in which the wide-area camera 20 captures an image of the laser light L while the laser light L is irradiated near the processing position P of the wiring pattern 2, but the present invention is not limited to this. For example, the wide-area camera 20 may capture an image of the laser light L while the laser light L is irradiated to a position other than the vicinity of the processing position P of the wiring pattern 2.

[0051] In addition, in the present embodiment, an example has been shown in which the laser light L irradiated in step S5 has an output smaller than the output of the laser light L irradiated when processing the wiring pattern 2, but the present invention is not limited to this. For example, the laser light L irradiated in step S5 may have an output equal to or greater than the output of the laser light L irradiated when processing the wiring pattern 2.

[0052] In addition, in the present embodiment, the laser light L irradiated in step S5 is a continuous wave, but the present invention is not limited to this. For example, the laser light L irradiated in step S5 may be an intermittent wave such as a pulsed wave.

[0053] Furthermore, in the present embodiment, an example has been shown in which the irradiation position of the laser light L is adjusted based on the amount of positional deviation between the coordinates (xb, yb) of the processing position P of the wiring pattern 2 shown in the workpiece image 70 and the coordinates (xc, yc) of the laser light L shown in the laser light image 80, but the present invention is not limited to this. For example, the irradiation position of the laser light L may be adjusted based on the luminance value of the laser light L in the captured image. In this case, for example, the irradiation position of the laser light L is adjusted based on the difference between the luminance value of the laser light L irradiated onto the workpiece and the luminance value of the laser light L irradiated onto areas other than the workpiece when the stage 40 is scanned within a predetermined range.

[0054] Furthermore, in the present embodiment, an example has been shown in which the stage 40 is moved to a position where the wide area camera 20 can capture an image of the processing position P of the wiring pattern 2 based on the coordinates (xa, ya) of the alignment mark R and the pre-stored positional relationship between the alignment mark R and the processing position P of the wiring pattern 2, but the present invention is not limited to this. For example, the stage 40 may be moved to a position where the wide area camera 20 can capture an image of the processing position P of the wiring pattern 2 without capturing an image of the alignment mark R.

[0055] Furthermore, in this embodiment, an example has been shown in which the alignment mark R is formed on the wafer 1, but the present invention is not limited to this. For example, the alignment mark R may be formed on the stage 40. Furthermore, the alignment mark R may be formed anywhere as long as it is separated from the workpiece by a predetermined distance.

[0056] In addition, in this embodiment, an example has been shown in which the alignment mark R is formed by photolithography, but the present invention is not limited to this. For example, the alignment mark R may be formed by metal vapor deposition or by applying paint or the like.

[0057] In addition, in the present embodiment, an example has been shown in which visible light is irradiated from the visible light illuminator 30 each time in step S2 and step S4, but the present invention is not limited to this. For example, visible light may be irradiated from the visible light illuminator 30 all the time during the processing of the laser processing method.

[0058] Furthermore, in the present embodiment, an example has been shown in which the workpiece image 70 and the laser light image 80 are acquired separately, but the present invention is not limited to this. For example, as in the captured image 90 according to a modified example shown in Fig. 8, the laser light L and the processing position P of the wiring pattern 2 may be captured simultaneously. In this case, the control unit 50 acquires an image captured by the wide-area camera 20 in a state in which the laser light L and visible light are irradiated simultaneously. [Explanation of symbols]

[0059] 2. Wiring pattern (workpiece) 10 Laser light irradiation unit 20 Wide-area camera (imaging unit) 50 control section 70 Workpiece image (captured image) 80 Laser light image (captured image) 100 Laser processing equipment L laser light P Machining position R Alignment mark (positioning mark) LC laser light irradiation position

Claims

1. A laser processing device that performs laser processing by irradiating a workpiece with laser light, a laser light irradiation unit that irradiates the laser light composed of invisible light other than visible light; a common imaging unit that images the laser light irradiated from the laser light irradiation unit and images the workpiece by forming an image of visible light; and a control unit that controls laser processing of the workpiece by adjusting the irradiation position of the laser light so that the laser light is irradiated at the processing position on the workpiece based on an image of the laser light and the workpiece captured by the common imaging unit.

2. The laser processing device according to claim 1 , wherein the image capturing unit is configured to capture an image of the laser light while the laser light is irradiated near a processing position on the workpiece.

3. 3. The laser processing apparatus according to claim 2, wherein the control unit controls the laser light irradiating unit so that, when the imaging unit images the laser light irradiated near the processing position on the workpiece, the laser light irradiating unit irradiates the laser light at a low output that is lower than an output of the laser light irradiated during the laser processing.

4. 4. The laser processing apparatus according to claim 3, wherein the control unit controls the laser light irradiating unit so that the laser light is irradiated at the low output and as a continuous wave when the imaging unit images the laser light irradiated near the processing position on the workpiece.

5. 2. The laser processing device according to claim 1, wherein the control unit is configured to acquire a deviation amount between the position of the laser light shown in an image captured by the common imaging unit and the position of the workpiece, and to adjust the irradiation position of the laser light based on the acquired deviation amount so that the laser light is irradiated onto a processing position on the workpiece.

6. the imaging unit is configured to capture an image of a positioning mark that is disposed at a position a predetermined distance away from the workpiece, 3. The laser processing device according to claim 2, wherein the control unit adjusts the imaging position of the imaging unit by moving the imaging unit and the workpiece relative to each other so that the processing position for the workpiece is imaged based on the position of the positioning mark imaged by the imaging unit, and causes the imaging unit to image the laser light and the workpiece.

7. A laser processing method for performing laser processing by irradiating a workpiece with laser light, comprising: an imaging step in which a common imaging unit images the laser light, which is composed of invisible light other than visible light and is irradiated from the laser light irradiation unit, and images the workpiece by forming an image of the visible light; an adjusting step of adjusting an irradiation position of the laser light based on an image of the laser light and the workpiece captured in the imaging step so that the laser light is irradiated at a processing position on the workpiece; a processing step of processing the workpiece by irradiating the workpiece with the laser light.

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