Laser processing device, laser processing method, laser processing program, recording medium, semiconductor chip manufacturing process and semiconductor chip

Abstract

The image of the portion of the semiconductor substrate W that overlaps the imaging area Ri is obtained by imaging the imaging area Ri, which moves relative to the semiconductor substrate W during the execution of the line processing (steps S1003 to S1004, S1103 to S1105) of the processing of the planned division line S by shining the laser beam B onto the laser irradiation position Lb while the laser irradiation position Lb is moved along the planned division line S (steps S1008, S1104). This means that the execution period of the line processing is effectively used to image the semiconductor substrate W. In this way, the semiconductor substrate W can be efficiently imaged in laser processing technology for processing the planned division line S by shining the laser beam B onto the planned division line S.

Description

TECHNICAL FIELD

[0001] This invention relates to a technique for machining a machining line by irradiating the machining line provided on a machining object with a laser beam. TECHNICAL BACKGROUND

[0002] Patent Literatures 1 to 3 describe a laser machining technique for machining a planned dividing line, in which a laser beam is moved relative to a semiconductor substrate while irradiating the laser beam onto the planned dividing line provided on the semiconductor substrate. For example, as shown in Patent Literature 1, in this laser machining technique, a plurality of planned dividing lines are machined sequentially by reciprocating a laser beam while changing the planned dividing line onto which the laser beam is irradiated in forward and backward paths.At this time, the laser beam can be precisely irradiated onto the planned dividing line by adjusting the position of the laser beam according to the result of alignment processing for detecting the position of the planned dividing line based on an image obtained by imaging a predetermined part of the semiconductor substrate (Patent Literature 2). As stated in Patent Literature 3, by machining the planned dividing line with the laser beam, a width of the planned dividing line can be expanded, and the position of the unmachined planned dividing line can be shifted in a feed direction orthogonal to a machining direction. To counteract such a position shift of the planned dividing line, it is appropriate to image the semiconductor substrate accordingly. LIST OF REFERENCES PATENT LITERATURE Patent Literature 1: Japanese Patent Publication No. 5804716 Patent Literature 2: Japanese Patent Publication No. 5554593 Patent Literature 3: Japanese Patent Publication No. 5037082 SUMMARY OF THE INVENTION TECHNICAL PROBLEM

[0003] In the laser processing technology described above, it is necessary to efficiently image a processing object (semiconductor substrate) in order to detect the influence of processing by irradiating a laser beam onto a processing line (planned parting line).

[0004] This invention has been developed in view of the problem mentioned above and aims to provide a technique that makes it possible to efficiently image a processing object in a laser processing technique for processing a processing line by irradiating the processing line with a laser beam. SOLUTION TO THE TASK

[0005] A laser processing apparatus according to the invention comprises: a support member that supports a processing object having a plurality of parallel processing lines such that the processing lines are parallel to a predetermined processing direction; a processing head that irradiates a laser beam to a predetermined laser irradiation position; a processing axis driver that moves the laser irradiation position in the processing direction relative to the processing object by driving the support member and / or the processing head in the processing direction;a control unit that performs line processing of the processing line by irradiating the laser beam from the processing head onto the laser irradiation position while moving the laser irradiation position along the processing line by the processing axis driver, and an imaging part that images a predetermined imaging region that moves relative to the processing object integrally with the laser irradiation position while the laser irradiation position moves relative to the processing object, the imaging part obtaining an image of a part of the processing object that overlaps the imaging region by imaging the imaging region that moves relative to the processing object while executing the line processing;

[0006] A laser machining method according to the invention comprises: supporting a machining object having a plurality of mutually parallel machining lines by a support member so that the machining lines are parallel to a predetermined machining direction; performing line machining of the machining line by irradiating a laser beam to a laser irradiation position by a machining head for irradiating the laser beam to a predetermined laser irradiation position, while the laser irradiation position is moved along the machining line by a machining axis driver to relatively move the laser irradiation position in the machining direction with respect to the machining object by driving the machining head and / or the support member in the machining direction;and obtaining an image of a part of the processing object overlapping an imaging region by an imaging part that images the imaging region moving relative to the processing object during execution of the line processing, the imaging part imaging a predetermined imaging region moving relative to the processing object integrally with the laser irradiation position while the laser irradiation position moves relative to the processing object;

[0007] In the invention (laser processing apparatus and laser processing method) configured in this way, the image of the part of the processing object that overlaps the imaging region is obtained by imaging the imaging region that moves relative to the processing object during the line processing of the processing line by irradiating the laser beam onto the laser irradiation position, while the laser irradiation position is moved along the processing line. This means that a line processing execution period is effectively utilized to image the processing object. In this way, the processing object can be efficiently imaged in a laser processing technique for processing the processing line by irradiating the laser beam onto the processing line.

[0008] The laser processing apparatus may be configured such that the imaging part images the imaging area provided on a downstream side of the processing line in a moving direction of the laser irradiation position during line processing. With such a configuration, an image of an unprocessed side of the position processed by the laser beam (i.e., the laser irradiation position) can be obtained. Therefore, based on this image, an influence of the processing by the laser beam on the unprocessed part of the processing object can be detected.

[0009] The laser processing device can be configured so that the imaging part images the imaging area multiple times during a single line processing execution period. In such a configuration, a plurality of images of the processing object can be obtained by effectively utilizing the line processing execution period.

[0010] The laser processing apparatus may further include a feed axis driver that moves the laser irradiation position in a feed direction orthogonal to the processing direction relative to the processing object by driving the support member and / or the processing head in the feed direction, wherein: among the plurality of processing lines, the processing line to be line-processed is changed by the feed axis driver that moves the laser irradiation position with respect to the processing object, the control unit sequentially performs a first line processing of processing a first processing line among the plurality of processing lines by the line processing of moving the laser irradiation position toward a first side in the processing direction and a second line processing of processing a second processing line different from the first processing line,from the plurality of processing lines by the line processing of moving the laser irradiation position toward a second side opposite the first side in the processing direction, the processing axis driver performs a reverse drive to bring the laser irradiation position to the second processing line by accelerating the laser irradiation position toward the second side after the laser irradiation position, which has passed through the first processing line toward the first side, is decelerated and stopped toward the first side in the processing direction, and the feed axis driver performs a continuous feed drive to move the laser irradiation position in the feed direction from a first imaginary straight line extending in the processing direction along the first processing line to the outside of the first processing line, to a second imaginary straight line,which extends in the machining direction along the second machining line to the outside of the second machining line, in a switching period from the end of the first line machining to the start of the second line machining, and the control unit causes the feed axis driver to move the laser irradiation position in the feed direction during the entire time before and after the time at which movement of the laser irradiation position in the machining direction is stopped due to the reverse drive, by controlling the machining axis driver and the feed axis driver such that the feed axis driver starts the continuous feed drive before the machining axis driver stops the laser irradiation position by the reverse drive, and the feed axis driver stops the continuous feed drive,after the machining axis driver stops the laser irradiation position by the reverse drive.

[0011] With such a configuration, the first line machining of the first machining line and the second line machining of the second machining line are performed using the machining axis driver to relatively move the laser irradiation position in the machining direction with respect to the machining object and the feed axis driver to relatively move the laser irradiation position in the feed direction with respect to the machining object. Furthermore, the machining axis driver and the feed axis driver perform the following operation to move the laser irradiation position that has passed through the first machining line toward the second machining line during the switching period between the first line machining and the second line machining.That is, the machining-axis driver performs reverse driving to move the laser irradiation position to the second machining line by accelerating the laser irradiation position toward the second side after the laser irradiation position, which has passed through the first machining line toward the first side, is decelerated and stopped toward the first side in the machining direction. Furthermore, the feed-axis driver moves the laser irradiation position in the feed direction from the first imaginary straight line extending outside the first machining line in the machining direction along the first machining line to the second imaginary straight line extending outside the second machining line in the machining direction along the second machining line.

[0012] In particular, the feed axis driver performs the continuous feed drive for continuously moving the laser irradiation position in the feed direction from the first imaginary straight line to the second imaginary straight line.The control unit causes the feed axis driver to move the laser irradiation position in the feed direction during the entire time before and after the time at which movement of the laser irradiation position in the machining direction is stopped due to the reverse drive, by controlling the machining axis driver and the feed axis driver such that the feed axis driver starts the continuous feed drive before the machining axis driver stops the laser irradiation position by the reverse drive, and the feed axis driver stops the continuous feed drive after the machining axis driver stops the laser irradiation position by the reverse drive.This means that, in the switching period, both a period of deceleration of the laser processing toward the first side in the processing direction and a period of acceleration of the laser irradiation position toward the second side in the processing direction are effectively utilized to move the laser irradiation position in the feed direction. As a result, it is possible to suppress the influence of the switching period for switching the movement direction of the laser beam on the time required to complete the processing of the processing object. Furthermore, since the execution period of the line processing is effectively utilized to image the processing object as described above, it is possible to suppress the time required to switch the processing line to line processing, efficiently image the processing object, and quickly complete the processing of the processing object.

[0013] The laser processing device can be configured such that, during line processing, the imaging part images the imaging area including at least the processing line. A part corresponding to the processing line appears to extend in the processing direction due to the contrast between both sides of the processing line and the processing line in the feed direction in the image obtained by such imaging. Therefore, the influence of laser processing on the position of the processing line in the feed direction can be precisely detected based on the position of this part in the feed direction.

[0014] The laser processing device can be configured such that a center of the imaging region of the imaging part and a focus of the laser beam to be irradiated to the laser irradiation position are arranged in the processing direction. With such a configuration, a state immediately before the laser beam is irradiated can be precisely captured through the image of the imaging region.

[0015] The laser processing device may be configured such that the imaging part acquires the image through full-space imaging to cause a camera to continue exposure during an overlap period during which an unprocessed part that has not been processed by irradiating the laser beam in a target line passes through the imaging area while performing line processing for the one target line among the plurality of processing lines. With such a configuration, information obtained by accumulating a luminance of the image of the imaging area in the processing direction can be obtained.

[0016] The laser processing device may be configured such that an exposure time Tc and an illuminance Tc in the full-time spatial image satisfy the following relationship for an exposure time T0 and an illuminance L0 when the camera images the processing object stationary with respect to the camera: Lc=T0×L0 / Tc.

[0017] With such a configuration, the luminance saturation of the image can be suppressed.

[0018] The laser processing device may be configured such that the control unit determines whether the laser irradiation position for the processing line is correct based on the image obtained by full-time space imaging. With such a configuration, it is possible to confirm whether the laser irradiation position is correct.

[0019] The laser processing device may be configured such that the control unit determines whether the laser irradiation position for the processing line is correct based on a central part of the image, excluding the two end parts in an orthogonal direction orthogonal to the processing direction. With such a configuration, it is possible to confirm whether the laser irradiation position is correct while excluding unnecessary information appearing in the two end parts in the orthogonal direction of the image.

[0020] The laser processing device may be configured such that, when line processing is performed along the one target line, the control unit acquires a positional deviation amount in the orthogonal direction of the laser irradiation position from the one target line and corrects the laser irradiation position based on the positional deviation in the orthogonal direction when confirming, based on the image, that there is a positional deviation of the laser irradiation position from the one target line in an orthogonal direction orthogonal to the processing direction. With such a configuration, line processing can be performed correctly by correcting the positional deviation of the laser irradiation position.

[0021] The laser processing device may be configured such that, when the inclination of a track of the laser irradiation position relative to the one target line is confirmed based on the image, the control unit performs alignment to correct the inclination. With such a configuration, line processing can be performed correctly by correcting the inclination of the laser irradiation position relative to the processing line.

[0022] A semiconductor chip manufacturing method according to the present invention includes: processing a semiconductor substrate having a plurality of semiconductor chips defined and lined up by processing lines by the above-described laser processing method; and separating each of the plurality of semiconductor chips by expanding a tape that holds the semiconductor substrate by an adhesive force, processed by the laser processing method.

[0023] A semiconductor chip according to the present invention is manufactured by: processing a semiconductor substrate having a plurality of semiconductor chips defined and arrayed by processing lines by the above-described laser processing method; and separating each of the plurality of semiconductor chips by expanding a tape that holds the semiconductor substrate by an adhesive force, processed by the laser processing method.

[0024] A laser processing program according to the invention causes a computer to carry out the laser processing method described above.

[0025] A recording medium according to the invention stores the laser processing program described above in a computer-readable manner. EFFECT OF THE INVENTION

[0026] According to the invention, a processing object can be efficiently imaged in a laser processing technique for processing a processing line by irradiating a laser beam onto the processing line. BRIEF DESCRIPTION OF THE DRAWINGS [ Fig. 1] Front view schematically showing an example of a laser processing apparatus according to the present invention. [ Fig. 2] Top view schematically showing the laser processing device of Fig. 1 shows. [ Fig. 3] Block diagram showing the electrical configuration of the laser processing device of Fig. 1 shows. [ Fig. 4] Flowchart showing an example of a method for manufacturing a laser-processed substrate in which laser processing has already been performed. [ Fig. 5] Flowchart showing an example of removing the ring frame. [ Fig. 6] Flowchart showing an example of ring frame transmission. [ Fig. 7A] Plan view schematically showing an example of a process carried out according to the flowcharts of Fig. 5 and Fig. 6 is carried out. [ Fig. 7B] Top view schematically showing an example of a process carried out according to the flowcharts of Fig. 5 and Fig. 6 is carried out. [ Fig. 7C] Top view schematically showing an example of a process carried out according to the flowcharts of Fig. 5 and Fig. 6 is carried out. [ Fig. 7D] Top view schematically showing an example of a process carried out according to the flowcharts of Fig. 5 and Fig. 6 is carried out. [ Fig. 7E] Top view schematically showing an example of a process carried out according to the flowcharts of Fig. 5 and Fig. 6 is carried out. [ Fig. 8] Flowchart showing an example of ring frame storage. [ Fig. 9] Flowchart showing an example of ring frame alignment. [ Fig. 10] Plan view schematically showing an example of an operation performed in ring frame alignment. [ Fig. 11] Flowchart showing an example of substrate processing. [ Fig. 12] Plan view schematically showing an example of a process carried out according to the flowchart of Fig. 11 is carried out. [ Fig. 13A] Flowchart showing an example of calibration. [ Fig. 13B] Flowchart showing an example of the stage level specification used in the calibration of Fig. 13A is carried out. [ Fig. 13C] Flowchart showing an example of the substrate level specification used in the calibration of Fig. 13A is carried out. [ Fig. 14] Flowchart showing the basic process of line editing for each planned dividing line. [ Fig. 15A] Diagram schematically showing a first example of a process carried out according to the flowchart of Fig. 14 is carried out. [ Fig. 15B] Diagram schematically showing a second example of the process according to the flowchart of Fig. 14 shows the process performed. [ Fig. 15C] Diagram schematically showing a third example of the process according to the flowchart of Fig. 14 shows the process performed. [ Fig. 15D] diagram schematically showing a fourth example of the process according to the flowchart of Fig. 14 shows the process performed [ Fig. 15E] Diagram schematically showing a fifth example of the process according to the flowchart of Fig. 14 shows the process performed [ Fig. 15F] Diagram schematically showing a sixth example of the process according to the flowchart of Fig. 14 shows the process performed. [ Fig. 15G] diagram schematically showing a seventh example of the process according to the flowchart of Fig. 14 shows the process performed. [ Fig. 16] Flowchart showing a first application example of line processing for each planned dividing line. [ Fig. 17] Diagram schematically showing an example of a process carried out according to the flowchart of Fig. 16 is carried out. [ Fig. 18] Flowchart showing a second application example of line processing for each planned dividing line. [ Fig. 19A] Diagram schematically showing a first example of a process carried out according to the flowchart of Fig. 18 is carried out. [ Fig. 19B] Diagram schematically showing a second example of the process according to the flowchart of Fig. 18 shows the process performed. [ Fig. 20] Diagram schematically showing an example of an image of the semiconductor substrate obtained in step S1008 of Fig. 16 or step S1104 of Fig. 18 was obtained. [ Fig. 21] Flowchart showing an example of a method for determining laser processing conditions in line processing. [ Fig. 22A] Diagram with parameters related to the determination of laser processing conditions. [ Fig. 22B] Diagram showing the temporal influence of laser processing conditions. [ Fig. 22C] Table with an example of a table to be used when determining the laser processing conditions from Fig. 21 must be referred to. [ Fig. 23] Plan view schematically showing a positional relationship of the laser irradiation position and the imaging regions in the detailed process of imaging the imaging regions. [ Fig. 24] Top view schematically showing an imaging object in the detailed process of imaging the imaging area. [ Fig. 25] Flowchart showing an example of camera exposure control. [ Fig. 26] Table schematically showing information obtained from panning images taken by the panning process. [ Fig. 27] Flowchart showing an example of image determination performed for the pan image. [ Fig. 28] Illustration showing schematically a method used in image determination Fig. 27 shows the mask used. DESCRIPTION OF THE EMBODIMENTS

[0027] Fig. 1 is a front view schematically showing an example of a laser processing apparatus according to the present invention, and Fig. 2 is a plan view schematically showing the laser processing apparatus of Fig. 1. In both and the subsequent figures, an X-direction, which is a horizontal direction, a Y-direction, which is a horizontal direction perpendicular to the X-direction, and a Z-direction, which is a vertical direction, are conveniently shown. Furthermore, a (+X) side in the X-direction (right side in Fig. 2) and a (-X) side (left side in Fig. 2) which is opposite to the (+X) side in the X direction, as appropriately shown, and a (+Y) side in the Y direction (upper side in Fig. 2) and a (-Y) side (lower side in Fig. 2) opposite the (+Y) side in the Y direction.

[0028] The laser processing apparatus 1 processes a semiconductor substrate W by irradiating a laser beam onto the semiconductor substrate W (processing object). This semiconductor substrate W is held by a ring frame Fr via a tape E. The tape E is a sawing foil or a bonding tape, and the front (top) surface of the tape E is adhesive. The ring frame Fr has an outer shape obtained by cutting parts of a regular octagon shape to provide slits Fs, and a circular opening Fo is provided at a center of the ring frame Fr. The front surface of the tape E faces the ring frame Fr from below to overlap the entire opening Fo, and the peripheral edge of the front surface of the tape E is bonded to the bottom surface of the ring frame Fr by an adhesive force. Further, the semiconductor substrate W is bonded to the front surface of the tape E by an adhesive force.The semiconductor substrate W is transported in the laser processing apparatus 1 while being held by the ring frame Fr via the belt E in this manner. Note that the semiconductor substrate W has a front surface and a back surface opposite to the front surface, and an electronic circuit is formed on the front surface of the semiconductor substrate W, while the back surface of the semiconductor substrate W is flat. The downward-facing front surface of the semiconductor substrate W is bonded to the front surface of the belt E, that is, the semiconductor substrate W is held with the back surface of the semiconductor substrate W facing upward.

[0029] The laser processing apparatus 1 is provided with a substrate storage part 2 for storing the semiconductor substrate W and a chuck 3 (support member) for holding the semiconductor substrate W taken out from the substrate storage part 2. The laser processing apparatus 1 is provided with a base plate 11 in the shape of a flat plate, and the substrate storage part 2 and the chuck 3 are supported by the base plate 11. The chuck 3 is arranged on the (+X) side of the substrate storage part 2 in the X direction and on the (-Y) side of the substrate storage part 2 in the Y direction. A space on the (-X) side of the chuck 3 in the X direction and on the (-Y) side of the substrate storage part 2 in the Y direction is a substrate transfer area Aw.

[0030] The substrate storage part 2 has a substrate storage cassette 21. The substrate storage cassette 21 includes a pair of side walls 22 provided on both sides in the X direction and an opening 23 provided between the side walls 22, and the opening 23 faces the (-Y) side (i.e., the substrate transfer area Aw). The pair of side walls 22 are flat plates perpendicular to the X direction and opposite to each other in the X direction. Further, support projections 24 are provided inside each of the pair of side walls 22. A pair of support projections 24 facing each other in the X direction are located at the same height. The ring frame Fr holding the semiconductor substrate W can be inserted from the (-Y) side via the opening 23 to a position above the pair of support projections 24.Both ends in the X direction of the ring frame Fr inserted in this way are supported from below by the pair of support projections 24. That is, a side above the pair of support projections 24 functions as a slot 25 for receiving the ring frame Fr, and the ring frame Fr inserted into the slot 25 from the (-Y) side via the opening 23 is supported by the pair of support projections 24 corresponding to this slot 25. Therefore, the semiconductor substrate W supported by the ring frame Fr can be stored in the substrate storage cassette 21 by inserting the ring frame Fr into the slot 25 of the substrate storage cassette 21, and the semiconductor substrate W can be removed from the substrate storage cassette 21 by pulling the ring frame Fr out of the slot 25 of the substrate storage cassette 21.

[0031] The substrate storage cassette 21 further includes a Z-axis slider 26 for supporting the substrate storage cassette 21 and a Z-axis drive mechanism 27 for driving the Z-axis slider 26 in the Z direction. The Z-axis drive mechanism 27 is a single-axis robot mounted on the base plate 11 and includes a Z-axis drive transducer 271 for supporting the Z-axis slider 26 movably in the Z direction and a Z-axis cassette motor 272 for driving the Z-axis slider 26 supported on the Z-axis drive transducer 271 in the Z direction. The Z-axis drive mechanism 271 includes a ball screw driven by the Z-axis cassette motor 272, and the Z-axis slider 26 is fixed to a ball screw nut. However, a specific configuration of the Z-axis drive mechanism 27 is not limited to this example and may be a linear motor.Such a Z-axis drive mechanism 27 moves the substrate storage cassette 21 mounted on the Z-axis slider 26 in the Z direction by driving the Z-axis slider 26 mounted on the Z-axis drive transformer 271 through the Z-axis cassette motor 272.

[0032] A substrate insertion height 211 is set for the substrate storage cassette 21, and the semiconductor substrate W can be inserted into and removed from the slot 25 located at the substrate insertion height 211. Therefore, the slot 25 into which the semiconductor substrate W is inserted and removed can be changed by moving the substrate storage cassette 21 in the Z direction by the Z-axis drive mechanism 27 to change the slot 25 located at the substrate insertion height 211 from a plurality of slots 25.

[0033] In contrast, the laser processing apparatus 1 is provided with a Y-axis conveying mechanism 4 for conveying the ring frame Fr in the Y direction between the slot 25 at the substrate insertion level 211 and the substrate transfer area Aw. The Y-axis conveying mechanism 4 includes a lifting hand 41, a Y-axis slider 43 for supporting the lifting hand 41, and a Y-axis driving mechanism 45 for driving the Y-axis slider 43 in the Y direction. The Y-axis drive mechanism 45 is a single-axis robot mounted on the base plate 11 by a frame not shown, and includes a Y-axis drive transformer 451 for supporting the Y-axis slider 43 movable in the Y direction, and a Y-axis lifting hand motor 452 for driving the Y-axis slider 43 supported on the Y-axis drive transformer 451 in the Y direction.The Y-axis drive transmission 451 includes a ball screw driven by the Y-axis lifting hand motor 452, and the Y-axis slider 43 is fixed to a ball screw nut. However, a specific configuration of the Y-axis drive mechanism 45 is not limited to this example and may be a linear motor. Such a Y-axis drive mechanism 45 moves the lifting hand 41 mounted on the Y-axis slider 43 in the Y direction by driving the Y-axis slider 43 mounted on the Y-axis drive transmission 451 through the Y-axis lifting hand motor 452.

[0034] The lifting hand 41 includes a base 411 supported on the Y-axis slider 43 and a fork 412 projecting from the base 411 toward the (+Y) side. The fork 412 is located at the substrate insertion height 211 and can hold the ring frame Fr from below. The Y-axis conveying mechanism 4 moves the ring frame Fr held by the fork 412 of the lifting hand 41 between the substrate storage cassette 21 and the substrate transfer area Aw by driving the lifting hand 41 in the Y direction through the Y-axis driving mechanism 45, as described later.

[0035] Further, the laser processing apparatus 1 is provided with an XZ-axis conveying mechanism 5 for conveying the ring frame Fr in the X direction between the lifting hand 41 located in the substrate transfer area Aw and the chuck 3. The XZ-axis conveying mechanism 5 includes a suction hand 51, an X-axis slider 53 for supporting the suction hand 51, and an X-axis driver 55 for driving the X-axis slider 53 in the X direction. The X-axis driver 55 is a single-axis robot mounted on the base plate 11 by a frame (not shown) and includes an X-axis drive transformer 551 for supporting the X-axis slider 53 movable in the X direction and an X-axis suction hand motor 552 for driving the X-axis slider 53 mounted on the X-axis drive transformer 551 in the X direction.The X-axis drive unit 551 includes a ball screw driven by the X-axis suction hand motor 552, and the X-axis slider 53 is fixed to a ball screw nut. However, a specific configuration of the X-axis driver 55 is not limited to this example and may be a linear motor. Such an X-axis driver 55 moves the suction hand 51 mounted on the X-axis slider 53 in the X direction by driving the X-axis slider 53 mounted on the X-axis drive unit 551 through the X-axis suction hand motor 552.

[0036] The XZ-axis conveying mechanism 5 further includes a Z-axis slider 56 attached to the suction hand 51, and a Z-axis driver 58 for driving the Z-axis slider 56 in the Z direction relative to the X-axis slider 53. That is, the suction hand 51 is supported by the Z-axis slider 56, and the Z-axis driver 58 is supported on the X-axis slider 53. The Z-axis driver 58 is a single-axis robot mounted on the X-axis slider 53 and includes a Z-axis drive linkage 581 for supporting the Z-axis slider 56 for movement in the Z direction, and a Z-axis suction hand motor 582 for driving the Z-axis slider 56 mounted on the Z-axis drive linkage 581 in the Z direction. The Z-axis drive linkage 581 includes a ball screw driven by the Z-axis suction motor 582, and the Z-axis slider 56 is fixed to a ball screw nut.However, a specific configuration of the Z-axis driver 58 is not limited to this example and may be a linear motor. The Z-axis slider 56 extends from the Z-axis driver 58 to a side below the X-axis drive transmitter 551, and the suction hand 51 is attached to the lower end of the Z-axis slider 56. Such a Z-axis driver 58 moves the suction hand 51 mounted on the Z-axis slider 56 in the Z direction by driving the Z-axis slider 56 mounted on the Z-axis drive transmitter 581 through the Z-axis suction hand motor 582.

[0037] The suction hand 51 includes a base 511 supported on the Z-axis slider 56 and an annular suction member 512 projecting toward the (+Y) side from the base 511. The annular suction member 512 has a circular ring shape, and a plurality of suction holes open into a bottom surface 513 of the annular suction member 512. The annular frame Fr can be held from above by the suction hand 51 by sucking the annular frame Fr by a negative pressure generated in each suction hole of the bottom surface 513, while bringing the bottom surface 513 of this annular suction member 512 into contact with the annular frame Fr from above.The XZ-axis conveying mechanism 5 moves the ring frame Fr held by the ring-shaped suction member 512 of the suction hand 51 between the substrate transfer area Aw and the chuck stage 3 by driving the suction hand 51 in the X direction by the X-axis driver 55 and the suction hand 51 in the Z direction by the Z-axis driver 58 as described later.

[0038] The clamping stage 3 includes a suction plate 31 on which the ring frame Fr, which supports the semiconductor substrate W via the belt E, is placed. The suction plate 31 has a circular shape, and a plurality of suction holes open into an upper surface 311 of the suction plate 31. The belt E can be attached to the suction plate 31 by sucking the belt E into contact with the upper surface 311 by a negative pressure generated in each suction hole of the upper surface 311 of the suction plate 31. Furthermore, the clamping stage 3 includes a plurality of clamps 32 provided on the peripheral edge of the suction plate 31. This clamping stage 3 fixes the ring frame Fr to the suction plate 31 by causing the clamps 32 to oppose the ring frame Fr placed on the suction plate 31 from above, and clamping the ring frame Fr between the clamps 32 and the suction plate 31.Furthermore, the clamping platform 3 releases the fastening of the ring frame Fr to the suction plate 31 by pulling the clamps 32 back laterally from the ring frame Fr.

[0039] As just described, the chuck 3 holds the semiconductor substrate W via the tape E on the ring frame Fr by sucking the tape E through the suction plate 31 and fixing the ring frame Fr through the clamps 32. By using the clamps 32 in combination in this way, the tape E can be sucked to the suction plate 31 with a weak suction force, and an influence of the suction force of the tape E on the semiconductor substrate W can be weakened compared to the case where the semiconductor substrate W is held only by sucking the tape E to the suction plate 31.

[0040] Furthermore, the laser processing device 1 is equipped with an XYΘ drive table 6 for supporting the clamping stage 3. The XYΘ drive table 6 is arranged on the base plate 11 and drives the clamping stage 3 in the X direction, the Y direction, and a Θ direction with respect to the base plate 11. The Θ direction is a rotational direction about a rotational axis parallel to the Z direction. This means that the XYΘ drive table 6 has a Y-axis guide 61 mounted on the base plate 11 parallel to the Y direction, a Y-axis slider 62 supported for movement in the Y direction by the Y-axis guide 61, and a Y-axis driver 63 for driving the Y-axis slider 62 in the Y direction.The Y-axis driver 63 is a single-axis robot mounted on the base plate 11 and includes a Y-axis drive unit 631 for supporting the Y-axis slider 62 for movement in the Y direction, and a Y-axis stage motor 632 for driving the Y-axis slider 62 supported on the Y-axis drive unit 631 in the Y direction. The Y-axis drive unit 631 includes a ball screw driven by the Y-axis stage motor 632, and the Y-axis slider 62 is fixed to a ball screw nut. However, the specific configuration of the Y-axis driver 63 is not limited to this example and may also be a linear motor.

[0041] The XYΘ drive table 6 further includes an X-axis slider 64 and an X-axis driver 65 for driving the X-axis slider 64 in the X direction relative to the Y-axis slider 62. The X-axis driver 65 is a single-axis robot mounted on the Y-axis slider 62 and includes an X-axis drive transformer 651 for supporting the X-axis slider 64 for movement in the X direction, and an X-axis table motor 652 for driving the X-axis slider 64 mounted on the X-axis drive transformer 651 in the X direction. The X-axis drive unit 651 includes a ball screw driven by the X-axis stage motor 652, and the X-axis slider 64 is fixed to a ball screw nut. However, the specific configuration of the X-axis driver 65 is not limited to this example and may also be a linear motor.

[0042] The XYΘ drive stage 6 further includes a Θ-axis stage motor 66 mounted on the X-axis slider 64. This Θ-axis stage motor 66 drives the clamping stage 3 in the Θ direction with respect to the X-axis slider 64.

[0043] Such an XYΘ drive table 6 can drive the clamping stage 3 in the Y direction by the Y-axis table motor 632, can drive the clamping stage 3 in the X direction by the X-axis table motor 652, and can drive the clamping stage 3 in the Θ direction by the Θ-axis table motor 66.

[0044] The laser processing apparatus 1 is further provided with a laser processing part 7 for performing laser processing on the semiconductor substrate W held on the chuck 3. The laser processing part 7 has a processing head 71 facing the semiconductor substrate W held on the chuck 3 from above. The processing head 71 includes a laser light source 72 for generating a laser beam B having a predetermined frequency and an optical system 73 (a lens, a diaphragm, and the like) for irradiating the laser beam B emitted from the laser light source 72 onto the semiconductor substrate W. This processing head 71 has a predetermined laser irradiation position Lb and faces the laser irradiation position Lb from above in the Z direction.The processing head 71 condenses the laser beam B emitted from the laser light source 72 onto the laser irradiation position Lb through the optical system 73, thereby forming a modified layer in a part of the semiconductor substrate W overlapping the laser irradiation position Lb.

[0045] The laser processing part 7 further includes a Z-axis slider 78 for supporting the processing head 71 and a Z-axis driver 79 for driving the Z-axis slider 78 in the Z direction. The Z-axis driver 79 is a single-axis robot mounted on the base plate and includes a Z-axis drive transformer 791 for supporting the Z-axis slider 78 for movement in the Z direction, and a Z-axis head motor 792 for driving the Z-axis slider 78 mounted on the Z-axis drive transformer 791 in the Z direction. The Z-axis drive transformer 791 includes a ball screw driven by the Z-axis head motor 792, and the Z-axis slider 78 is fixed to a ball screw nut. However, a specific configuration of the Z-axis driver 79 is not limited to this example and may be a linear motor.Such a Z-axis driver 79 moves the laser irradiation position Lb of an infrared camera 81 in the Z direction by driving the Z-axis slider 78 supported on the Z-axis drive transformer 791 through the Z-axis head motor 792 to move the machining head 71 supported on the Z-axis slider 78 in the Z direction.

[0046] The laser processing apparatus 1 is further provided with imaging parts 8 for imaging the semiconductor substrate W held on the chuck stage 3. More specifically, two imaging parts 8 are arranged across the laser processing part 7 in the X direction. To distinguish these two imaging parts 8, the imaging part 8 on the (+X) side of the laser processing part 7 is referred to as imaging part 8A, and the imaging part 8 on the (-X) side of the laser processing part 7 is referred to as imaging part 8B. In this way, the imaging part 8A, the laser processing part 7, and the imaging part 8B are lined up in the X direction. Note that each of the imaging parts 8A, 8B has a common basic configuration. Therefore, the components common to the imaging parts 8A, 8B will be described without distinction.

[0047] The imaging part 8 includes the infrared camera 81, which faces the semiconductor substrate W held on the chuck 3 from above. This infrared camera 81 has a predetermined imaging area Ri (in other words, a field of view) and faces this imaging area Ri from above in the Z direction. The infrared camera 81 images the imaging area Ri by detecting the infrared rays emitted from the imaging area Ri and obtaining an image of the imaging area Ri.

[0048] The imaging part 8 further includes a Z-axis slider 88 for supporting the infrared camera 81 and a Z-axis driver 89 for driving the Z-axis slider 88 in the Z direction. The Z-axis driver 89 is a single-axis robot mounted on the base plate and includes a Z-axis drive transformer 891 for supporting the Z-axis driver 88 for movement in the Z direction, and a Z-axis camera motor 892 for driving the Z-axis slider 88 mounted on the Z-axis drive transformer 891 in the Z direction. The Z-axis drive unit 891 includes a ball screw driven by the Z-axis camera motor 892, and the Z-axis slider 88 is fixed to a ball screw nut. However, the specific configuration of the Z-axis driver 89 is not limited to this example and may be a linear motor.Such a Z-axis driver 89 moves the imaging area Ri of the infrared camera 81 in the Z-direction by driving the Z-axis slider 88 supported by the Z-axis camera motor 892 on the Z-axis drive transformer 891 to move the infrared camera 81 supported on the Z-axis slider 88 in the Z-direction.

[0049] Note that the infrared camera 81 of the imaging part 8A and the infrared camera 81 of the imaging part 8B have different resolutions. Specifically, the infrared camera 81 of the imaging part 8A has a higher resolution, that is, a narrower field of view, than the infrared camera 81 of the imaging part 8B. However, the resolutions of the infrared cameras 81 do not need to be different between the imaging parts 8A and 8B, and these infrared cameras 81 may have the same resolution. Furthermore, in this example, the center points of the imaging area Ri of the imaging part 8A, the laser irradiation position Lb of the machining head 71, and the imaging area Ri of the imaging part 8B are arranged parallel to the X direction.However, these do not necessarily have to be parallel to the X direction, and the imaging area Ri of the imaging part 8A only needs to be on the (+X) side and the imaging area Ri of the imaging part 8B only needs to be on the (-X) side with respect to the laser irradiation position Lb of the processing head 71.

[0050] Fig. 3 is a block diagram showing the electrical configuration of the laser processing device of Fig. 1 shows. As in Fig. 3, the laser processing device 1 is provided with a control unit 100 for controlling the Fig. 1 and Fig. 2 are provided. The control unit 100 includes a handling control computer 110 responsible for controlling a substrate transport system (substrate storage part 2, Y-axis conveying mechanism 4, and XZ-axis conveying mechanism 5) related to the transport of the semiconductor substrate W in the laser processing apparatus 1, and a laser processing control computer 120 responsible for controlling a laser processing system (chuck stage 3, XYθ drive table 6, laser processing part 7, and imaging parts 8) related to the laser processing of the semiconductor substrate W.

[0051] The control unit 100 further includes a cassette controller 111 for controlling the insertion and removal of the semiconductor substrate W into and from the substrate storage cassette 21 in response to a command from the handling control computer 110. This cassette controller 111 adjusts the position in the Z direction of the substrate storage cassette 21 by controlling the Z-axis cassette motor 272 and adjusts the position in the Y direction of the lifting hand 41 by controlling the Y-axis lifting hand motor 452.

[0052] The control unit 100 further includes a hand controller 112 for controlling a conveying operation of the semiconductor substrate W by the suction hand 51 in response to a command from the handling control computer 110. The hand controller 112 adjusts the position in the X direction of the suction hand 51 by controlling the X-axis suction hand motor 552 and adjusts the position in the Z direction of the suction hand 51 by controlling the Z-axis suction hand motor 582. Furthermore, the hand controller 112 controls a suction pump 591 for sucking the suction holes in the bottom surface 513 of the annular suction member 512 of the suction hand 51. That is, the hand controller 112 sucks the annular frame Fr through the suction hand 51 by supplying negative pressure to the suction holes through the suction pump 591, and separates the annular frame Fr from the suction hand 51 by stopping the supply of negative pressure to the suction holes through the suction pump 591.

[0053] The control unit 100 further includes a stage controller 121 for controlling a substrate fixing operation by the chuck stage 3 and the drive of the chuck stage 3 in response to a command from the laser processing control computer 120. The stage controller 121 adjusts the positions in the X-direction, the Y-direction, and the Θ-direction of the chuck stage 3 by controlling the X-axis stage motor 652, the Y-axis stage motor 632, and the Θ-axis stage motor 66. Furthermore, the stage controller 121 controls the fixing of the ring frame Fr to the suction plate 31 and the release of the fixing by a clamp drive 691 by controlling the clamp drive 691 to drive the clamps 32. Furthermore, the stage controller 121 controls a suction pump 692 for sucking the suction holes in the top side 311 of the suction plate 31.That is, the stage controller 121 sucks the tape E through the suction plate 31 by supplying negative pressure to the suction holes through the suction pump 692, and releases the suction of the tape E through the suction plate 31 by stopping the supply of negative pressure to the suction holes through the suction pump 692.

[0054] The control unit 100 further includes a camera controller 122A for controlling the imaging part 8A and a camera controller 122B for controlling the imaging part 8B. These hand controllers 112A, 112B perform the following controls for the infrared cameras 81 and the Z-axis camera motors 892 of the imaging parts 8A, 8B, which are respectively these targets. That is, each of the camera controllers 122A, 122B causes the infrared camera 81 to image the semiconductor substrate W to acquire an image of the semiconductor substrate W, and drives the infrared camera 81 in the Z direction through the Z-axis camera motor 892 to adjust a distance in the Z direction from the infrared camera 81 to the semiconductor substrate W.

[0055] The control unit 100 further includes a machining head controller 123 for controlling the laser machining part 7. The machining head controller 123 drives the laser light source 72 to emit a laser beam B from the laser light source 72 and drives the machining head 71 in the Z direction through the Z-axis head motor 792 to adjust a distance in the Z direction from the machining head 71 to the semiconductor substrate W. The machining head 71 further includes a height detector 74 for detecting a height (distance in the Z direction) from the semiconductor substrate W. This height detector 74 is a so-called distance sensor. The optical system 73 of the machining head 71 further includes a focusing mechanism 75. The focusing mechanism 75 adjusts a position to which the laser beam B is focused by shifting a focus of the optical system 73 in the Z direction.Specifically, the machining head controller 123 focuses the laser beam B at a predetermined position within the semiconductor substrate W by controlling the focusing mechanism 75 based on the height of the machining head 71 from the semiconductor substrate W detected by the height detector 74.

[0056] It is noted that each function of the control unit 100 described above can be realized by a processor such as a CPU (Central Processing Unit), an FPGA (Field Programmable Gate Array), etc.

[0057] The control unit 100 further includes a memory 190, which is a storage device such as an HDD (Hard Disk Drive) or an SDD (Solid State Drive). A laser processing program 191 for specifying operations described later, which are performed in the laser processing apparatus 1 for laser processing the semiconductor substrate W, is stored in this memory 190. This means that the control unit 100 executes any control that is to be performed later based on the Fig. 4 to 22C, by implementing the laser processing program 191. Note that the laser processing program 191 is provided from a recording medium 192 external to the laser processing apparatus 1, and the control unit 100 (computer) reads the laser processing program 191 recorded on the recording medium 192 and stores the laser processing program 191 in the memory 190. Examples of such a recording medium 192 include a USB (Universal Serial Bus) memory, a storage device of an external computer, and the like.

[0058] Fig. 4 is a flowchart showing an example of a method for manufacturing a laser-processed substrate for which laser processing has already been performed. The flowchart of Fig. 4 is executed according to a control of the control unit 100 based on the laser processing program 191. In step S101, the lifting hand 41 removes the ring frame Fr from the substrate storage cassette 21 into the substrate transfer area Aw. In step S102, the suction hand 51 in the substrate transfer area Aw transfers the ring frame Fr from the lifting hand 41 to the clamping stage 3. In this way, the semiconductor substrate W held by the ring frame Fr is removed from the substrate storage cassette 21 into the substrate transfer area AW and then transferred from the substrate transfer area Aw to the clamping stage 3. Specifically, the removal of the ring frame from Fig. 5 in step S101 and the transfer of the ring frame from Fig. 6 in step S102.

[0059] Fig. 5 is a flowchart showing an example of removing the ring frame, Fig. 6 is a flowchart showing an example of the transfer of the ring frame, and Fig. 7A to 7E are plan views schematically showing an example of a process carried out according to the flowcharts of Fig. 5 and Fig. 6 is carried out.

[0060] In step S201 of the Fig. 5, the control unit 100 confirms whether the lifting hand 41 is empty or not, that is, whether the ring frame Fr is not placed on the lifting hand 41. Whether the lifting hand 41 is empty or not can be confirmed based on a history or the like of operations performed by the lifting hand 41. The flowchart of Fig. 5 is terminated if the lifting hand 41 is not empty ("NO" in step S201), whereas if the lifting hand 41 is empty ("YES" in step S201), it proceeds to step S201.

[0061] In step S202, the control unit 100 confirms whether or not at least a part of the lifting hand 41 is located inside the substrate storage cassette 21, that is, on the inside (ie, (+Y) side) of the substrate storage cassette 21 other than the opening 23 of the substrate storage cassette 21. Whether or not at least a part of the lifting hand 41 is located inside the substrate storage cassette 21 can be confirmed, for example, from the position of the lifting hand 41 indicated by an output of an encoder of the Y-axis lifting hand motor 452 for driving the lifting hand 41 in the Y direction. It proceeds to S204 without executing step S203 when the lifting hand 41 is retracted to the (-Y) side from the substrate storage cassette 21 ("NO" in step S202), while it proceeds to step S203 when a part of the lifting hand 41 is located in the substrate storage cassette 21 ("YES" in step S202).In step S203, the control unit 100 pulls out the lifting hand 41 from the substrate storage cassette 21 toward the (-Y) side and retracts the lifting hand 41 toward the (-Y) side of the substrate storage cassette 21 by driving the lifting hand 41 toward the (-Y) side by the Y-axis lifting hand motor 452.

[0062] In step S204, the control unit 100 positions the slot 25 in which the ring frame Fr is stored at a position higher than the substrate insertion height 211 by a predetermined height by driving the substrate storage cassette 21 in the Z direction by the Z-axis cassette motor 272. This predetermined height is shorter than a distance between the slots 25 adjacent in the Z direction. Thus, the bottom surface of the ring frame Fr to be removed is set to a position higher than the lifting hand 41 by the predetermined height.

[0063] In step S205, the control unit 100 sets as in Fig. 7A, the lifting hand 41 is inserted into the substrate storage cassette 21 by driving the lifting hand 41 toward the (+Y) side by the Y-axis lifting hand motor 452. Thus, the lifting hand 41 faces the ring frame Fr and can be removed from below via a gap.

[0064] In step S206, the control unit 100 lowers the substrate storage cassette 21 in the Z direction by means of the Z-axis cassette motor 272. Therefore, the ring frame Fr to be removed is placed on the lifting hand 41 and moved upward with respect to the slot 25 (ie, the pair of support projections 24 defining the slot 25).

[0065] In step S207, the control unit 100 retracts the lifting hand 41 into the substrate transfer area Aw provided outside the substrate storage cassette 21 by driving the lifting hand 41 toward the (-Y) side by the Y-axis lifting hand motor 452. In this way, as shown in Fig. 7B, the ring frame Fr placed on the lifting hand 41 in the substrate transfer area Aw.

[0066] In step S301 of the Fig. 6, the control unit 100 causes the suction hand 51 to face the ring frame Fr supported in the substrate transfer area Aw on the lifting hand 41 from above, as shown in Fig. As shown in Figure 7C, the position in the X direction of the suction hand 51 is adjusted by the X-axis suction hand motor 552. At this time, the control unit 100 adjusts the suction hand 51 to a position higher than the ring frame Fr by adjusting the height of the suction hand 51 by the Z-axis suction hand motor 582. Therefore, the suction hand 51 faces the ring frame Fr across a gap.

[0067] In step S302, the control unit 100 brings the bottom surface 513 of the suction hand 51 into contact with the upper surface of the ring frame Fr by lowering the suction hand 51 with respect to the ring frame Fr through the Z-axis drive transformer 581. In step S303, the control unit 100 causes the suction pump 591 to generate negative pressure in the suction holes provided in the bottom surface 513 of the suction hand 51, and the suction hand 51 sucks the ring frame Fr through this negative pressure. In this way, the ring frame Fr is held by the suction hand 51. In step S304, the control unit 100 lifts the suction hand 51 through the Z-axis suction hand motor 582. In this way, the suction hand 51 lifts the ring frame Fr from the lifting hand 41.

[0068] In step S305, the control unit 100 causes the suction hand 51 to point from above the clamping stage 3 as the transfer destination of the ring frame Fr by driving the suction hand 51 by the X-axis suction hand motor 552 toward the (+X) side, as shown in Fig. 7D. At this time, the control unit 100 sets the ring frame Fr held by the suction hand 51 to a position higher than the chuck stage 3 by adjusting the height of the suction hand 51 by the Z-axis suction hand motor 582. Therefore, the ring frame Fr held by the suction hand 51 faces the chuck stage 3 across a gap.

[0069] In step S306, the control unit 100 places the ring frame Fr (and the belt E) held by the suction hand 51 onto the suction plate 31 of the clamping stage 3 by lowering the suction hand 51 by the Z-axis suction hand motor 582. In step S307, the control unit 100 releases the suction of the ring frame Fr by the suction hand 51 by stopping the suction pump 591.

[0070] In step S308, the control unit 100 confirms whether or not the transfer destination of the ring frame Fr is the clamping stage 3. If the transfer destination of the ring frame Fr is, for example, the lifting hand 41 as in step S104, which will be described later, it is determined "NO" in step S308, and the flowchart of Fig. 6 is completed. Since the transfer destination of the ring frame Fr is the clamping stage 3, "YES" is determined in step S308, and the process proceeds to S309.

[0071] In step S309, the control unit 100 clamps the ring frame Fr placed on the suction plate 31 of the clamping stage 3 between the clamps 32 and the suction plate 31 to clamp the ring frame Fr by driving the clamps 32 by the clamp driver 691. Further, in step S310, the control unit 100 causes the suction pump 591 to generate negative pressure in the suction holes provided in the upper surface 311 of the suction plate 31, and the suction plate 31 sucks the tape E connected to the ring frame Fr by this negative pressure. In this way, the ring frame Fr is held by the clamping stage 3. In step S311, the control unit 100 lifts the suction hand 51 by the Z-axis suction hand motor 582. This causes the suction hand 51 to retract upwards from the ring frame Fr held on the clamping platform 3. In this way, as in Fig. 7E, the transfer of the ring frame Fr from the substrate storage cassette 21 to the clamping stage 3 is completed (steps S101, S102 of Fig. 4).

[0072] In step S103 of the Fig. 4, substrate processing is performed to process the semiconductor substrate W held on the chuck stage 3 by the laser beam B, and the laser beam B is irradiated onto the plurality of planned dividing lines provided on the semiconductor substrate W. This substrate processing will be described in detail later.

[0073] When the substrate processing is completed, steps S104, S105 are performed. In step S104, the suction hand 51 transfers the ring frame Fr from the chuck stage 3 to the lifting hand 41 in the substrate transfer area Aw. In step S105, the lifting hand 41 places the ring frame Fr from the substrate transfer area Aw into the substrate storage cassette 21. In this way, the semiconductor substrate W held on the ring frame Fr is stored in the substrate storage cassette 21 from the substrate transfer area Aw after being transferred from the chuck stage 3 to the substrate transfer area Aw. Specifically, the transfer of the ring frame from Fig. 6 in step S104, the storage of the ring frame of Fig. 8 is performed in step S105, and a process similar to that in Fig. The process opposite to that shown in Figures 7A to 7E is performed. Fig. Figure 8 is a flowchart showing an example of ring frame storage.

[0074] Since the process performed in step S104 of Fig. 6 the process performed in step S102 of Fig. 6, the description will focus on the differences from the above process, and the description of common process parts will be omitted where appropriate. In step S301 of Fig. 6, the control unit 100 causes the suction hand 51 to face the ring frame Fr placed on the clamping stage 3 from above by adjusting the position in the X direction of the suction hand 51 with the X-axis suction hand motor 552. Then, the control unit 100 lowers the suction hand 51 onto the ring frame Fr (step S302) and causes the suction hand 51 to suck the ring frame Fr (step S303). Subsequently, the control unit 100 lifts the suction hand 51 (step S304). In this way, the suction hand 51 lifts the ring frame Fr from the clamping stage 3.

[0075] In step S305, the control unit 100 drives the suction hand 51 toward the (-X) side by the X-axis suction hand motor 552. At this time, the lifting hand 41 is in a standby position in the substrate transfer area Aw. In this way, the suction hand 51 points from above the lifting hand 41 into the substrate transfer area Aw as the transfer destination of the ring frame Fr. Then, the control unit 100 places the ring frame Fr held by the suction hand 51 on the lifting hand 41 by lowering the suction hand 51 by the Z-axis suction hand motor 582 (step S306). Then, the control unit 100 releases the suction of the ring frame Fr by the suction hand 51 by stopping the suction pump 591 (step S307). In step S308, the control unit 100 confirms whether the transfer destination of the ring frame Fr is the clamping stage 3 or not.Since the transfer destination of the ring frame Fr here is not the clamping stage 3 but the lifting hand 41, “NO” is determined in step S308, and the flowchart of . Fig. 6 is finished.

[0076] In step S401 of Fig. 8, the control unit 100 confirms whether or not the ring frame Fr has been placed on the lifting hand 41. The placement of the ring frame Fr on the lifting hand 41 can be confirmed, for example, based on a history of operations of the suction hand 51 for placing the ring frame Fr. If the placement of the ring frame Fr on the lifting hand 41 is confirmed ("YES" in step S401), the control unit 100 confirms whether or not at least a part of the lifting hand 41 is located in the substrate storage cassette 21 (step S402), as described in step S202 above. It proceeds to step S404 without performing step S403 when the lifting hand 41 is retracted to the (-Y) side from the substrate storage cassette 21 ("NO" in step S402), while it proceeds to step S403 when a part of the lifting hand 41 is located in the substrate storage cassette 21 ("YES" in step S402).In step S403, the control unit 100 retracts the lifting hand 41 toward the (-Y) side of the substrate storage cassette 21 and retracts the lifting hand 41 toward the (-Y) side from the substrate storage cassette 21 by driving the lifting hand 41 toward the (-Y) side by the Y-axis lifting hand motor 452.

[0077] In step S404, the control unit 100 positions the slot 25 (in other words, the pair of support protrusions 24 specifying the slot 25) in which the ring frame Fr is to be stored, at a position lower than the substrate insertion height 211 by a predetermined height by driving the substrate storage cassette 21 in the Z direction by the Z-axis cassette motor 272. In this way, the storage slot 25 is set to a position lower than the bottom surface of the ring frame Fr supported by the lifting hand 41 by the predetermined height.

[0078] In step S405, the control unit 100 inserts the lifting hand 41 into the substrate storage cassette 21 by moving the lifting hand 41 toward the (+Y) side by the Y-axis lifting hand motor 452. Thus, the pair of support protrusions 24 defining the storage slot 25 faces the ring frame Fr from below across a gap, supported on the lifting hand.

[0079] In step S406, the control unit 100 lifts the substrate storage cassette 21 in the Z direction by the Z-axis cassette motor 272. Thus, the ring frame Fr is placed on the pair of support protrusions 24 defining the storage slot 25 and lifted relative to the lifting hand 41. In step S407, the control unit 100 retracts the lifting hand 41 outside the substrate storage cassette 21 by driving the lifting hand 41 toward the (-Y) side by the Y-axis lifting hand motor 452.

[0080] It is noted that when taking out or storing the ring frame Fr from or into the substrate storage cassette 21, ring frame alignment Fr may be performed with respect to the lifting hand 41. Fig. 9 is a flowchart showing an example of ring frame alignment, and Fig. Figure 10 shows plan views schematically showing an example of a process performed in ring frame alignment. It is noted that the flowchart in Fig. 9 is carried out by a control of the control unit 100.

[0081] In Fig. 10, elements (alignment protrusions 413 and the like) are shown below the suction hand 51 through the suction hand 51. This means that the lifting hand 41 in this example has a plurality of alignment protrusions 413 projecting upward from the base part 41. The plurality of these alignment protrusions 413 correspond to the plurality of slots Fs of the ring frame Fr. The ring frame alignment is performed using the alignment protrusions 413 and the slots Fs.

[0082] During this ring frame alignment, the ring frame Fr is sucked onto the lifting hand 41 by the suction hand 51 (step S501). Then, the suction hand 51 holding the ring frame Fr is lifted to separate the ring frame Fr upward from the lifting hand 41 (step S502). At this time, a separation height of the ring frame Fr from the lifting hand 41 is adjusted so that the ring frame Fr is located at a height between the lower and upper ends of the alignment protrusions 413 in the Z direction.

[0083] In step S503, an XYΘ floating mechanism 561 built into the Z-axis slider 56 is turned on. This XYΘ floating mechanism 561 selectively assumes a floating state for floatingly supporting the suction hand 51 and a locking state for fixedly supporting the suction hand 51. Here, floating support means supporting the suction hand 51 in a state where the suction hand 51 can move in the X direction, the Y direction, and the Θ direction with respect to the XYΘ floating mechanism 561, and fixed support means supporting the suction hand 51 in a state where the suction hand 51 is fixed to the XYΘ floating mechanism 561. When the XYΘ floating mechanism 561 is turned on in step S503, the XYΘ floating mechanism 561 floatingly supports the suction hand 51, and the suction hand 51 becomes movable in the X direction, the Y direction, and the Θ direction with respect to the XYΘ floating mechanism 561.

[0084] In step S504, the lifting hand 41 moves in the Y direction, and the alignment protrusions 413 of the lifting hand 41 are brought into contact with the peripheral edge of the ring frame Fr held by the suction hand 51. At this time, the suction hand 51 moves with respect to the XYΘ floating mechanism 561 so that the alignment protrusions 413 follow the peripheral edge of the ring frame Fr. As a result, as shown in the field of step S504 of Fig. 10, the respective alignment projections 413 of the lifting hand 41 are engaged with the respective slots Fs of the ring frame Fr, and the ring frame Fr is positioned with respect to the lifting hand 41.

[0085] In step S505, the XYΘ floating mechanism 561 is locked. Thus, the suction hand 51 is firmly held by the XYΘ floating mechanism 561. Then, in step S506, the suction of the ring frame Fr by the suction hand 51 is released, and the ring frame Fr is placed on the lifting hand 41. In step S507, the XYΘ floating mechanism 561 is turned off, and the suction hand 51 is supported by the Z-axis slider 56 while being fixed to the Z-axis slider 56. In this way, the ring frame Fr can be positioned with respect to the lifting hand 41 (ring frame alignment).

[0086] Next, substrate processing is described in detail. Fig. 11 is a flowchart showing an example of substrate processing, and Fig. 12 shows plan views schematically showing an example of a process carried out according to the flowchart of Fig. 11 is carried out. The flow chart of the Fig. 11 is carried out by a control of the control unit 100.

[0087] In step S601 of the substrate processing of Fig. 11, a calibration is performed to obtain a plane of the upper surface (back surface) of the semiconductor substrate W to be processed. Fig. 13A is a flowchart showing an example of calibration, Fig. Figure 13B is a flowchart showing an example of the stage level specification used in the calibration of Fig. 13A is carried out, and Fig. Figure 13C is a flowchart showing an example of the substrate level specification used in the calibration of Fig. 13A. It is noted that when calibrating Fig. 13A, the suction plate 31 or the semiconductor substrate W is imaged as needed. In this description, it is assumed that imaging is performed by the imaging part 8B. However, the following operation can be performed similarly even when imaging is performed by the imaging part 8A.

[0088] In step S701 of the calibration of Fig. 13A the stage level specification ( Fig. 13B). As in Fig. As shown in Fig. 13B, in the stage level specification, a count value I for distinguishing a plurality of (three) imaging points Ps(I) provided on the upper surface 311 of the suction plate 31 of the clamping stage 3 is reset to zero (step S801), and the count value I is incremented by 1 (step S802). The imaging point Ps(I) is, for example, a mark having a predetermined pattern.

[0089] In step S803, the control unit 100 causes the imaging point Ps(I) to face the infrared camera 81 from below by adjusting the position of the chuck 3 through the XYθ drive table 6. Thus, the imaging point Ps(I) falls within a field of view of the infrared camera 81. In step S803, the infrared camera 81 images this imaging point Ps(I) and acquires an image showing the imaging point Ps(I). In step S804, the control unit 100 confirms whether or not the predetermined pattern of the imaging point Ps(I) can be detected from the image by image processing such as pattern recognition.

[0090] If a focus of the infrared camera 81 deviates from the imaging point Ps(I) and the predetermined pattern cannot be detected from the image ("NO" in step S804), the control unit 100 changes a distance of the infrared camera 81 to the imaging point Ps(I) in the Z direction by driving the infrared camera 81 in the Z direction through the Z-axis camera motor 892 (step S805). In this way, the focus of the infrared camera 81 is changed in the Z direction. Steps S803 to S805 are repeated until the focus of the infrared camera 81 coincides with the imaging point Ps(I) and the predetermined pattern is detected ("YES" in step S804).

[0091] In step S806, the control unit 100 calculates the position (X, Y, Z) of the imaging point Ps(I) based on the predetermined pattern detected from the image obtained by imaging the imaging point Ps(I). The X and Y coordinates of the imaging point Ps(I) are calculated based on the position of the predetermined pattern contained in the image. A Z coordinate of the imaging point Ps(I) is calculated based on the position of the infrared camera 81 in the Z direction when the image from which the predetermined pattern could be detected was imaged.

[0092] In step S807, it is confirmed whether the count value I has reached 2, that is, the positions (X, Y, Z) of two pixels Ps(1), Ps(2) have been obtained. If the count value I is less than 2 ("NO" in step S807), the process returns to step S802 and performs steps S802 to S806. If the count value I is equal to 2 ("YES" in step S807), the process proceeds to step S808.

[0093] In step S808, a rotation angle Θa for rotating the clamping stage 3 in the Θ direction is calculated such that a straight line passing through the two imaging points Ps(1) and Ps(2) is horizontal. If a difference from the current rotation angle of the suction plane 31 (difference between a current rotation angle and the rotation angle Θa) is not zero ("NO" in step S809), the clamping stage 3 is rotated by the rotation angle Θa (step S810), and a return to step S801 occurs. In this way, steps S801 to S809 are performed.

[0094] If the difference from the current rotation angle of the suction plane 31 (difference between the current rotation angle and the rotation angle Θa) is zero ("YES" in step S809), the process proceeds to step S811. In step S811, the control unit 100 images the imaging point Ps(3) through the infrared camera 81 and acquires an image showing the imaging point Ps(3) in the same manner as in step S803. In step S812, the control unit 100 confirms whether or not a predetermined pattern included in the imaging point Ps(3) can be detected from this image by image processing such as pattern recognition.

[0095] If the predetermined pattern cannot be detected from the image ("NO" in step S812), the control unit 100 changes the distance of the infrared camera 81 to the imaging point Ps(3) in the Z direction by driving the infrared camera 81 in the Z direction with the Z-axis camera motor 892 (step S813). Steps S811 to S813 are repeated until the predetermined pattern is detected ("YES" in step S812).

[0096] If the predetermined pattern can be detected in step S812 (YES), the control unit 100 calculates the position (X, Y, Z) of the imaging point Ps(3) based on the predetermined pattern detected from the image obtained by imaging the imaging point Ps(3) (step S814). In this way, the position (X, Y, Z) of each of the three imaging points Ps(1), Ps(2), and Ps(3) is obtained. In step S815, a plane passing through these three positions (X, Y, Z) is set as a plane representing the plane of the chuck 3, specifically, the upper surface 311 of the suction plane 31.

[0097] In step S702 of the calibration of Fig. 13A, the substrate level specification ( Fig. 13C). As in Fig. As shown in Fig. 13C, in the substrate plane specification, a count value I for distinguishing a plurality of (three) imaging points Pw(I) of the semiconductor substrate W is reset to zero (step S901), and the count value I is incremented by 1 (step S902). The imaging points Pw(I) are, for example, an area having a predetermined pattern.

[0098] Specifically, the semiconductor substrate W, as shown in Fig. 12, in the form of a lattice by planned dividing lines S (Sa, Sb) orthogonal to each other. That is, the semiconductor substrate W is provided with a plurality of the planned dividing lines Sa parallel to each other and a plurality of the planned dividing lines Sb parallel to each other, and the planned dividing lines Sa and the planned dividing lines Sb are orthogonal to each other. In this way, a plurality of semiconductor chips C are lined up in a lattice via the planned dividing lines Sa, Sb. In contrast, an area including an intersection point of the planned dividing line Sa and the planned dividing line Sb (in other words, a point surrounded by the semiconductor chips C arranged at four corners) is set as an imaging point Pw(I).Since the back surface of the semiconductor substrate W faces upward as described above, the infrared camera 81 images the planned dividing lines Sa, Sb and the semiconductor chips C formed on the front surface of the semiconductor substrate W through the back surface of the semiconductor substrate W with infrared rays.

[0099] In step S903, the control unit 100 causes the imaging point Pw(I) to face the infrared camera 81 from below by adjusting the position of the chuck 3 through the XYθ drive table 6. In this way, the imaging point Pw(I) falls within the field of view of the infrared camera 81. In step S903, the infrared camera 81 images this imaging point Pw(I) and acquires an image showing the imaging point Pw(I). In step S904, the control unit 100 confirms whether or not a predetermined pattern (for example, a cutting pattern of the planned parting lines Sa, Sb) included in the imaging point Pw(I) can be detected from this image by image processing such as pattern recognition.

[0100] If the focus of the infrared camera 81 deviates from the imaging point Pw(I) and the predetermined pattern cannot be detected from the image ("NO" in step S904), the control unit 100 changes a distance of the infrared camera 81 to the imaging point Pw(I) in the Z direction by driving the infrared camera 81 in the Z direction through the Z-axis camera motor 892 (step S905). In this way, the focus of the infrared camera 81 is changed in the Z direction. Steps S903 to S905 are repeated until the focus of the infrared camera 81 coincides with the imaging point Pw(I) and the predetermined pattern is detected ("YES" in step S904).

[0101] It is noted that the plane (stage plane) representing the upper surface 311 of the suction plane 31 is determined by the previously performed stage plane specification ( Fig. 13B). Accordingly, a height range in which the imaging point Pw(I) of the semiconductor substrate W disposed on the suction plane 31 exists can be estimated based on this stage plane. Therefore, in step S805, the height of the infrared camera 81 is changed so that the focus of the infrared camera 81 falls within a range in which the imaging point Pw(I) estimated from the stage plane exists.

[0102] In step S906, the control unit 100 calculates the position (X, Y, Z) of the imaging point Pw(I) based on the predetermined pattern detected from the image obtained by imaging the imaging point Pw(I). The X and Y coordinates of the imaging point Pw(I) are calculated based on the position of the predetermined pattern contained in the image. A Z coordinate of the imaging point Pw(I) is calculated based on the position of the infrared camera 81 in the Z direction when the image from which the predetermined pattern could be detected was imaged.

[0103] In step S907, it is confirmed whether the count value I has reached 2, that is, the positions (X, Y, Z) of two pixels Ps(1), Ps(2) have been obtained. If the count value I is less than 2 ("NO" in step S907), the process returns to step S902 and performs steps S902 to S906. If the count value I is equal to 2 ("YES" in step S902), the process proceeds to step S908.

[0104] In step S908, based on the two mapping points Pw(1) and Pw(2), a rotation angle Ob for rotating the clamping platform 3 in the Θ direction is calculated so that the planned parting lines Sa run parallel to the X direction (machining direction). If a difference from the current rotation angle of the suction plane 31 (difference between a current rotation angle and the rotation angle Θb) is not zero ("NO" in step S909), the clamping platform 3 is rotated by the rotation angle Θb (step S910), and a return to step S901 occurs. In this way, steps S901 to S909 are executed.

[0105] If the difference from the current rotation angle of the suction plane 31 (difference between the current rotation angle and the rotation angle Ob) is zero ("YES" in step S909), the process proceeds to step S911. In step S911, the control unit 100 captures the imaging point Pw(3) with the infrared camera 81 and acquires an image showing the imaging point Pw(3) in the same manner as in step S903. In step S912, the control unit 100 confirms whether or not a predetermined pattern included in the imaging point Pw(3) can be detected from this image by image processing such as pattern recognition.

[0106] If the predetermined pattern cannot be detected from the image ("NO" in step S912), the control unit 100 changes the distance of the infrared camera 81 to the imaging point Pw(3) in the Z direction by driving the infrared camera 81 in the Z direction with the Z-axis camera motor 892 (step S913). Steps S911 to S913 are repeated until the predetermined pattern is detected ("YES" in step S912). At this time, a range for changing the height of the infrared camera 81 is set based on the stage level, as in the aforementioned case.

[0107] If the predetermined pattern can be detected in step S912 (YES), the control unit 100 calculates the position (X, Y, Z) of the imaging point Pw(3) based on the predetermined pattern detected from the image obtained by imaging the imaging point Pw(3) (step S914). In this way, the position (X, Y, Z) of each of the three imaging points Pw(1), Pw(2), and Pw(3) is obtained. In step S915, a plane passing through these three positions (X, Y, Z) is set as a plane representing the semiconductor substrate W.

[0108] With reference to Fig. 11, the description continues. When the semiconductor substrate W is positioned so that the planned dividing lines Sa are parallel to the X direction and the plane constituting the semiconductor substrate W is determined by performing the calibration described above (step S601), the line processing (step S602) is performed for each planned dividing line Sa. That is, each of the plurality of planned dividing lines Sa is processed by the laser beam B by performing the line processing for irradiating the laser beam B onto the laser irradiation position Lb while moving the laser irradiation position Lb in the X direction along the target planned dividing line Sa while changing the target planned dividing line Sa from the plurality of planned dividing lines Sa. Specifically, as described in the field of step S602 of Fig. 12, the line processing of moving the laser irradiation position Lb toward the (+X) side in the X direction and the line processing of moving the laser irradiation position Lb toward the (-X) side in the X direction are alternately performed.

[0109] At this time, by driving the chuck 3 holding the semiconductor substrate W toward the (-X) side by the X-axis driver 65, the laser beam B is moved toward the (+X) side with respect to the planned dividing line Sa, and by driving the chuck 3 holding the semiconductor substrate W toward the (+X) side by the X-axis driver 65, the laser beam B is moved toward the (-X) side with respect to the planned dividing line Sa. Furthermore, by driving the chuck 3 holding the semiconductor substrate W in the Y direction by the Y-axis driver 63, the planned dividing line Sa of the line processing is changed.The control unit 100 further performs control for adjusting the position in the Z direction of the infrared camera 81 by the Z-axis camera motor 892 based on the plane representing the semiconductor substrate W specified by the calibration of step S601. In this way, a converging position of the laser beam B is adjusted inside the semiconductor substrate W, and a modified layer is formed inside the semiconductor substrate W along the planned dividing lines Sa.

[0110] When the line machining for each of the plurality of scheduled dividing lines Sa is completed in this way (step S602), the chuck 3 holding the semiconductor substrate W is rotated by 90° in the Θ direction by the Θ-axis table motor 66. In this way, a change is made from a state in which the plurality of scheduled dividing lines Sa on which the line machining has been performed are positioned parallel to the X direction (field “S602_e” of Fig. 12), to a state in which the plurality of planned dividing lines Sb are positioned parallel to the X direction (field “S603” of the Fig. 12).

[0111] In step S604, calibration is performed as in step S601 described above. Furthermore, in step S605, line processing is performed for each of the plurality of planned dividing lines Sb as in step S602 described above.

[0112] Fig. 14 is a flowchart showing a basic process of line processing for each planned dividing line, and Fig. 15A shows diagrams schematically showing a first example of a process performed according to the flowchart of Fig. 14 is carried out. In Fig. In FIG. 15A, a track of the laser irradiation position Lb moving relative to the semiconductor substrate W is represented by a dotted line, and imaginary straight lines Sv1, Sv2, Sv3 extending parallel to the X direction along the planned dividing lines S1, S2, S3 between the two outer sides of the planned dividing lines S1, S2, S3 are represented by a single-dot chain line. Note that the dotted lines representing the track of the laser irradiation position Lb are preferably shown in the parts where the track of the laser irradiation position Lb and the imaginary straight lines Sv1, Sv2, Sv3 intersect.

[0113] In the Fig. 15A, the flowchart of Fig. 14 is started from a state in which the laser irradiation position Lb is stopped at a position Pb1 on the (-X) side of the semiconductor substrate W in the X direction. This position Pb1 is a position provided on the imaginary straight line Sv1 along the planned dividing line S1, in other words, facing the planned dividing line S1 from the X direction. The position of the laser irradiation position Lb at the start of the flowchart of Fig. However, paragraph 14 is not limited to this example and may be modified as appropriate.

[0114] In step S1001, the laser irradiation position Lb stopped at position Pb1 begins to accelerate in the X direction toward the (+X) side and moves parallel to the X direction. At this time, the laser irradiation position Lb moves along the imaginary straight line Sv1 toward the (+X) side. When a speed Vx of the laser irradiation position Lb increases to a processing speed Vxd until the laser irradiation position Lb reaches one end of the semiconductor substrate W on the (-X) side, the laser irradiation position Lb moves toward the (+X) side in the X direction at the constant processing speed Vxd (step S1002).

[0115] Further, the laser light source 72 is turned on, and irradiation of the laser beam B onto the laser irradiation position Lb from the machining head 71 is started according to a timing at which the laser irradiation position Lb reaches the end of the semiconductor substrate W on the (-X) side (step S1003). Further, the laser light source 72 is turned off, and irradiation of the laser beam B onto the laser irradiation position Lb from the machining head 71 is stopped according to a timing at which the laser irradiation position Lb reaches an end of the semiconductor substrate W on the (+X) side (step S1004). In this way, during a period from step S1003 to step S1004, laser machining for the planned dividing line S1 is performed by irradiating the laser beam B onto the laser irradiation position Lb while moving the laser irradiation position Lb toward the (+X) side along the planned dividing line S1 (line machining).

[0116] When the laser irradiation position Lb passes the planned dividing line S1 toward the (+X) side, the laser irradiation position Lb begins to decelerate toward the (+X) side in the X direction (step S1005) and stops at a position Pb2 on the (+X) side of the semiconductor substrate W in the X direction (step S1006). This position Pb2 is a position provided on the imaginary straight line Sv2 adjacent to the imaginary straight line Sv1 in the Y direction, in other words, facing the planned dividing line S2 from the X direction. This means that in steps S1005 to S1006, the laser irradiation position Lb moves in the Y direction from the imaginary straight line Sv1 to the imaginary straight line Sv2 parallel to the deceleration in the X direction.

[0117] A positional relationship between the imaging areas Ri ( Fig. 1) of the imaging parts 8A, 8B and the laser irradiation position Lb of the processing head 71 is fixed. Therefore, in steps S1001 to S1006, as the laser irradiation position Lb moves relative to the semiconductor substrate W, the imaging regions Ri also move relatively with respect to the semiconductor substrate W. When the laser irradiation position Lb is stopped at position Pb2, the imaging region Ri of the imaging part 8B stops at a position including at least one imaging point Pw(S2). This imaging point Pw(S2) is an intersection point where the planned dividing line S2 and the planned dividing line S orthogonal to the line S2 intersect in the semiconductor substrate W. Accordingly, in step S1006, the control unit 100 causes the imaging part 8B to image the imaging region Ri and acquire an image including the imaging point Pw(S2).Thereby, the control unit 100 can obtain an image showing the position of the unprocessed planned dividing line S2.

[0118] In step S1007, it is confirmed whether or not laser processing is completed for the plurality of planned dividing lines S parallel to the X direction. If there is any unprocessed planned dividing line S among these planned dividing lines S ("NO" in step S1007), the process returns to step S1001.

[0119] In the example of Fig. 15A, the laser irradiation position Lb stopped at position Pb2 begins to accelerate in the X direction toward the (-X) side in step S1001 and moves parallel to the X direction. At this time, the laser irradiation position Lb moves along the imaginary straight line Sv2 toward the (-X) side. When the speed Vx of the laser irradiation position Lb increases to the processing speed Vxd by the time the laser irradiation position Lb reaches the end of the semiconductor substrate W on the (+X) side, the laser irradiation position Lb moves toward the (-X) side in the X direction at the constant processing speed Vxd (step S1002).

[0120] At this time, a position at which the laser irradiation position Lb, which has passed the planned dividing line S1 toward the (+X) side, starts to decelerate (in other words, an X coordinate at which the movement at a constant speed toward the (+X) side is finished), and a position at which the laser irradiation position Lb, which accelerates toward the (-X) side toward the planned dividing line S, stops accelerating (in other words, an X coordinate at which the movement at a constant speed toward the (-X) side starts), coincide.That is, the X coordinate at which the constant speed movement of the laser irradiation position Lb, which has passed the planned dividing line Sn to which the line processing is to be performed in the nth revolution, is stopped and the deceleration is started, and the X direction at which the laser irradiation position Lb, which has moved to the planned dividing line Sn+1 to which the line processing is to be performed in the (n+1). ten rotation is to be performed, the acceleration stops and the movement starts at constant speed, coincide.

[0121] Further, the laser light source 72 is turned on, and the irradiation of the laser beam B onto the laser irradiation position Lb from the machining head 71 is started according to a timing at which the laser irradiation position Lb reaches the end of the semiconductor substrate W on the (+X) side (step S1003). Further, the laser light source 72 is turned off, and the irradiation of the laser beam B onto the laser irradiation position Lb from the machining head 71 is stopped according to a timing at which the laser irradiation position Lb reaches the end of the semiconductor substrate W on the (-X) side (step S1004). In this way, during a period from step S1003 to step S1004, laser machining for the planned dividing line S2 is performed by irradiating the laser beam B onto the laser irradiation position Lb while moving the laser irradiation position Lb toward the (-X) side along the planned dividing line S2 (line machining).

[0122] When the laser irradiation position Lb passes the planned dividing line S2 toward the (-X) side, the laser irradiation position Lb begins to decelerate toward the (-X) side in the X direction (step S1005) and stops at a position Pb3 on the (-X) side of the semiconductor substrate W in the X direction (step S1006). This position Pb3 is a position provided on the imaginary straight line Sv3 adjacent to the imaginary straight line Sv2 in the Y direction, in other words, opposite to the planned dividing line S3 from the X direction. This means that in steps S1005 to S1006, the laser irradiation position Lb moves in the Y direction from the imaginary straight line Sv2 to the imaginary straight line Sv3 parallel to the deceleration in the X direction.

[0123] When the laser irradiation position Lb is stopped at the position Pb3, the imaging area Ri of the imaging part 8A stops at a position including at least one imaging point Pw(S3). This imaging point Pw(S3) is an intersection point of the planned dividing line S3 and the planned dividing line S orthogonal to this line S3 in the semiconductor substrate W. Accordingly, in step S1006, the control unit 100 causes the imaging part 8A to image the imaging area Ri and acquire an image including the imaging point Pw(S3). In this way, the control unit 100 can acquire an image showing the position of the unprocessed planned dividing line S3.

[0124] Steps S1001 to S1007 are repeated until it is confirmed that the line machining for the plurality of planned division lines S (S1, S2, S3, ...) parallel to the X direction is completed ("YES" in step S1007).

[0125] Next, a speed change of the laser irradiation position Lb is expressed by referring to a “speed change in the X direction” and a “speed change in the Y direction” in Fig. 15A. Here, the speed Vx indicates a speed at which the laser irradiation position Lb is moved in the X direction with respect to the semiconductor substrate W, and the speed Vy indicates a speed at which the laser irradiation position Lb is moved in the Y direction with respect to the semiconductor substrate W. Further, the machining speed Vxd indicates a speed at which the laser irradiation position Lb is moved at a constant speed in the X direction along the planned parting line S (ie, the speed Vx), and is represented by an absolute value regardless of the movement to the (+X) side or the movement to the (-X) side.

[0126] In a line processing period Ts1 (steps S1002 to S1004) during which the line processing of moving the laser beam B toward the (+X) side along the planned dividing line S1 is performed, the laser irradiation position Lb does not move in the Y direction while moving in the X direction at the constant processing speed Vxd. Further, in a line processing period Ts2 (steps S1002 to S1004) during which the line processing of moving the laser beam B toward the (-X) side along the planned dividing line S2 is performed, the laser irradiation position Lb does not move in the Y direction while moving in the X direction at the constant processing speed Vxd.

[0127] In a switching period Tc (steps S1005, S1006, and S1001) in which the line processing period Ts1 is switched to the line processing period Ts2, the following operation is performed. That is, the X-axis driver 65 (processing axis driver) performs reverse driving to bring the laser irradiation position Lb to the intended dividing line S2 (second processing line) by accelerating the laser irradiation position Lb toward the (-X) side (step S1001) after decelerating and stopping the laser irradiation position Lb that has passed the intended dividing line S1 (first processing line) toward the (+X) side (first side) in the X direction (processing direction) (step S1005).In parallel with this reversing movement, the Y-axis driver 63 (feed axis driver) moves the laser irradiation position Lb in the Y direction (feed direction) from the imaginary straight line Sv1 (first imaginary straight line) extended outward in the X direction from the planned dividing line S1 along the planned dividing line S1 to the imaginary straight line Sv2 (second imaginary straight line) extended outward in the X direction from the planned dividing line S2 along the planned dividing line S2 (second machining line).

[0128] Specifically, the switching period Tc includes a deceleration period Td (step S1005) for decelerating the laser irradiation position Lb in the X direction and an acceleration period Ta (step S1001) for accelerating the laser irradiation position Lb in the X direction, and movement of the laser irradiation position Lb in the Y direction is performed during the deceleration period Td outside the deceleration period Td and the acceleration period Ta. Specifically, the movement of the laser irradiation position Lb in the Y direction is started after the start of the deceleration period Td, and the movement of the laser irradiation position Lb in the Y direction is completed before the end of the deceleration period Td. Furthermore, the laser irradiation position Lb does not move in the Y direction during the acceleration period Ta.

[0129] Here, a start point of the delay period Td indicates a time point at which the deceleration of the laser irradiation position Lb in the X direction is started (ie, a decrease in the absolute value of the speed Vx from the machining speed Vxd begins), and an end point of the delay period Td indicates a time point at which the speed of the laser irradiation position Lb in the X direction (ie, the speed Vx) becomes zero.A start point of the acceleration period Ta indicates a time point at which the acceleration of the laser irradiation position Lb in the X direction is started (in other words, an increase in the absolute value of the speed Vx from zero begins), and an end point of the acceleration period Ta indicates a time point at which the acceleration of the laser irradiation position Lb in the X direction is completed (in other words, a time point at which the absolute value of the speed Vx becomes the machining speed Vxd).

[0130] Further, in a stop period Tt provided en route during a transition from the acceleration period Ta to the deceleration period Td, both the speed Vx of the laser irradiation position Lb in the X direction and its speed Vy in the Y direction become zero, and the laser irradiation position Lb is stopped at the position Pb2 with respect to the semiconductor substrate W. In this stop period Tt, the imaging areas Ri of the imaging parts 8A, 8B are also stopped with respect to the semiconductor substrate W. Specifically, the imaging area Ri of the imaging part 8B is located on the (-X) side of the laser irradiation position Lb, which is located on the (+X) side of the semiconductor substrate W, and overlaps the semiconductor substrate W. Accordingly, the infrared camera 81 of the imaging part 8B images a part of the semiconductor substrate W that overlaps the imaging area Ri in the stop period Tt (step S1006).

[0131] Fig. 15B shows diagrams schematically showing a second example of the process according to the flowchart of Fig. 14. The notation in Fig. 15B is similar to the one in Fig. 15A. Also in Fig. 15B, the laser processing is carried out sequentially for the planned dividing lines S1, S2, S3 according to the flow chart of Fig. 14 as in Fig. 15A carried out. Fig. However, 15B differs from Fig. 15A is to be laser processed by the process in the switching period Tc to change the planned dividing line S. Accordingly, the following description focuses on the differences to Fig. 15A, and common operating parts are designated by corresponding reference numerals, and the description is omitted where appropriate.

[0132] When the laser irradiation position Lb passes the planned dividing line S1 toward the (+X) side, once the laser processing for the planned dividing line S1 is completed, the laser irradiation position Lb begins to decelerate toward the (+X) side in the X direction (step S1005) and stops at a position Pb2 on the (+X) side of the semiconductor substrate W in the X direction (step S1006). This position Pb2 is a position provided on the imaginary straight line Sv1. When the laser irradiation position Lb stops at the position Pb2, the imaging area Ri of the imaging part 8B stops at a position including at least one imaging point Pw(S2). Accordingly, in step S1006, the control unit 100 causes the imaging part 8B to image the imaging area Ri and acquire an image including the imaging point Pw(S2).In this way, the control unit 100 can obtain the image showing the position of the unprocessed planned dividing line S2.

[0133] Subsequently, the laser irradiation position Lb, which was stopped at the position Pb2, begins to accelerate in the X direction toward the (-X) side (step S1001). When the speed Vx of the laser irradiation position Lb increases to the machining speed Vxd by the time the laser irradiation position Lb reaches the end of the semiconductor substrate W on the (+X) side, the laser irradiation position Lb moves toward the (-X) side in the X direction at the constant machining speed Vxd (step S1002). Further, in a period between the start of the acceleration and the start of the constant movement, the laser irradiation position Lb moves from the imaginary straight line Sv1 to the imaginary straight line Sv2 in the Y direction at the machining speed Vxd.This means that in steps S1001 to S1002, the laser irradiation position Lb moves in the Y direction from the imaginary straight line Sv1 to the imaginary straight line Sv2 parallel to the acceleration in the X direction. Thus, the laser irradiation position Lb reaches the planned dividing line S2, and line processing for the planned dividing line S2 can be started.

[0134] When the laser irradiation position Lb passes the planned dividing line S2 toward the (-X) side, once the laser processing for the planned dividing line S2 is completed, the laser irradiation position Lb begins to decelerate toward the (-X) side in the X direction (step S1005) and stops at a position Pb3 on the (-X) side of the semiconductor substrate W in the X direction (step S1006). This position Pb3 is a position provided on the imaginary straight line Sv2. When the laser irradiation position Lb is stopped at the position Pb3, the imaging area Ri of the imaging part 8A stops at a position including at least one imaging point Pw(S3). Accordingly, in step S1006, the control unit 100 causes the imaging part 8A to image the imaging area Ri and acquire an image including the imaging point Pw(S3).In this way, the control unit 100 can obtain the image showing the position of the unprocessed planned dividing line S3.

[0135] Next, a speed change of the laser irradiation position Lb is expressed by referring to a “speed change in the X direction” and a “speed change in the Y direction” in Fig. 15B. In a line machining period Ts1 (steps S1002 to S1004) during which the line machining of moving the laser beam B toward the (+X) side along the scheduled dividing line S1 is performed, the laser irradiation position Lb does not move in the Y direction while moving in the X direction at the constant machining speed Vxd. Further, in a line machining period Ts2 (steps S1002 to S1004) during which the line machining of moving the laser beam B toward the (-X) side along the scheduled dividing line S2 is performed, the laser irradiation position Lb does not move in the Y direction while moving in the X direction at the constant machining speed Vxd.

[0136] Further, in a switching period Tc (steps S1005, S1006, and S1001) during which switching occurs from the line processing period Ts1 to the line processing period Ts2, the laser irradiation position Lb is moved in the Y direction (feed direction) from the imaginary straight line Sv1 to the imaginary straight line Sv2, in parallel with performing the reverse travel in the X direction as in the aforementioned case. Specifically, a movement of the laser irradiation position Lb in the Y direction is performed during an acceleration period Ta consisting of a deceleration period Td and the acceleration period Ta included in the switching period Tc. Specifically, the movement of the laser irradiation position Lb in the Y direction is started after the start of the acceleration period Ta, and the movement of the laser irradiation position Lb in the Y direction is completed before the end of the acceleration period Ta.In addition, the laser irradiation position Lb does not move in the Y direction during the delay period Td.

[0137] Further, in a stop period Tt provided en route during a transition from the acceleration period Ta to the deceleration period Td, both the speed Vx of the laser irradiation position Lb in the X direction and its speed Vy in the Y direction become zero, and the laser irradiation position Lb is stopped at the position Pb2 with respect to the semiconductor substrate W. In this stop period Tt, the imaging areas Ri of the imaging parts 8A, 8B are also stopped with respect to the semiconductor substrate W. Specifically, the imaging area Ri of the imaging part 8B is located on the (-X) side of the laser irradiation position Lb, which is located on the (+X) side of the semiconductor substrate W, and overlaps the semiconductor substrate W. Accordingly, the infrared camera 81 of the imaging part 8B images a part of the semiconductor substrate W that overlaps the imaging area Ri in the stop period Tt (step S1006).

[0138] Fig. Figure 15C schematically shows a third example of a process carried out according to the flowchart of Fig. 14. The notation in Fig. 15C is similar to the Fig. 15A. Also in Fig. 15C, the laser processing is carried out sequentially for the planned dividing lines S1, S2, S3 according to the flow chart of Fig. 14 as in Fig. 15A carried out. Fig. However, 15C differs from Fig. 15A by the process in the switching period Tc for switching the planned dividing line S to be machined with the laser. Accordingly, the following description focuses on the differences from Fig. 15A, and common operating parts are designated by corresponding reference numerals, and the description is omitted where appropriate.

[0139] When the laser irradiation position Lb passes the planned parting line S1 toward the (+X) side, once the laser processing for the planned parting line S1 is completed, the laser irradiation position Lb begins to decelerate toward the (+X) side in the X direction (step S1005) and stops at a position Pb2 on the (+X) side of the semiconductor substrate W in the X direction (step S1006). This position Pb2 is provided between the imaginary straight lines Sv1 and Sv2 in the Y direction. This means that in steps S1005 to S1006, the laser irradiation position Lb moves in the Y direction from the imaginary straight line Sv1 to the position Pb2 parallel to the deceleration in the X direction. When the laser irradiation position Lb is stopped at the position Pb2, the imaging area Ri of the imaging part 8B stops at a position including at least one imaging point Pw (S2).Accordingly, in step S1006, the control unit 100 causes the imaging part 8B to image the imaging area Ri and acquire an image including the imaging point Pw (S2). In this way, the control unit 100 can acquire the image showing the position of the unprocessed planned dividing line S2.

[0140] Subsequently, the laser irradiation position Lb, which was stopped at the position Pb2, begins to accelerate in the X direction toward the (-X) side (step S1001). When the speed Vx of the laser irradiation position Lb increases to the machining speed Vxd by the time the laser irradiation position Lb reaches the end of the semiconductor substrate W on the (+X) side, the laser irradiation position Lb moves toward the (-X) side in the X direction at the constant machining speed Vxd (step S1002). Further, in a period between the start of the acceleration and the start of the constant movement, the laser irradiation position Lb moves at the machining speed Vxd in the Y direction from the position Pb2 to the imaginary straight line Sv2.This means that in steps S1001 to S1002, the laser irradiation position Lb moves in the Y direction from the position Pb2 to the imaginary straight line Sv2 parallel to the acceleration in the X direction. Thus, the laser irradiation position Lb reaches the planned dividing line S2, and line processing for the planned dividing line S2 can be started.

[0141] When the laser irradiation position Lb passes the planned parting line S2 toward the (-X) side, once the laser processing for the planned parting line S2 is completed, the laser irradiation position Lb begins to decelerate toward the (-X) side in the X direction (step S1005) and stops at a position Pb3 on the (-X) side of the semiconductor substrate W in the X direction (step S1006). This position Pb3 is provided between the imaginary straight line Sv2 and the imaginary straight line Sv3. This means that in steps S1005 to S1006, the laser irradiation position Lb moves in the Y direction from the imaginary straight line Sv2 to the position Pb3 parallel to the deceleration in the X direction. When the laser irradiation position Lb is stopped at the position Pb3, the imaging area Ri of the imaging part 8A stops at a position including at least the imaging point Pw (S3).Accordingly, in step S1006, the control unit 100 causes the imaging part 8A to image the imaging area Ri and acquire an image including the imaging point Pw (S3). In this way, the control unit 100 can acquire the image showing the position of the unprocessed planned dividing line S3.

[0142] Next, a speed change of the laser irradiation position Lb is expressed by referring to a “speed change in the X direction” and a “speed change in the Y direction” in Fig. 15C. In a line machining period Ts1 (steps S1002 to S1004) during which the line machining of moving the laser beam B toward the (+X) side along the scheduled dividing line S1 is performed, the laser irradiation position Lb does not move in the Y direction while moving in the X direction at the constant machining speed Vxd. Further, in a line machining period Ts2 (steps S1002 to S1004) during which the line machining of moving the laser beam B toward the (-X) side along the scheduled dividing line S2 is performed, the laser irradiation position Lb does not move in the Y direction while moving in the X direction at the constant machining speed Vxd.

[0143] Furthermore, in a switching period Tc (steps S1005, S1006, and S1001) in which switching occurs from the line processing period Ts1 to the line processing period Ts2, the laser irradiation position Lb is moved in the Y direction (feed direction) from the imaginary straight line Sv1 to the imaginary straight line Sv2, in parallel with performing the reverse travel in the X direction as in the aforementioned case. Specifically, this movement of the laser irradiation position Lb is performed via the position Pb2. That is, the laser irradiation position Lb moves in the Y direction from the imaginary straight line Sv1 to the position Pb2 in a deceleration period Td, under the deceleration period Td and an acceleration period Ta included in the switching period Tc, and moves in the Y direction from the position Pb2 to the imaginary straight line Sv2 in the acceleration period Ta.Specifically, the laser irradiation position Lb starts moving from the imaginary straight line Sv1 to the position Pb2 at the same time as the start of the deceleration period Td, and reaches the position Pb2 at the same time as the end of the deceleration period Td. Furthermore, the laser irradiation position Lb starts moving from the position Pb2 to the imaginary straight line Sv2 at the same time as the start of the acceleration period Ta, and reaches the imaginary straight line Sv2 at the same time as the end of the acceleration period Ta.

[0144] Further, in a stop period Tt provided en route during a transition from the acceleration period Ta to the deceleration period Td, both the speed Vx of the laser irradiation position Lb in the X direction and its speed Vy in the Y direction become zero, and the laser irradiation position Lb is stopped at the position Pb2 with respect to the semiconductor substrate W. In this stop period Tt, the imaging areas Ri of the imaging parts 8A, 8B are also stopped with respect to the semiconductor substrate W. Specifically, the imaging area Ri of the imaging part 8B is located on the (-X) side of the laser irradiation position Lb, which is located on the (+X) side of the semiconductor substrate W, and overlaps the semiconductor substrate W. Accordingly, the infrared camera 81 of the imaging part 8B images a part of the semiconductor substrate W that overlaps the imaging area Ri in the stop period Tt (step S1006).

[0145] It is noted that the concrete manner of moving the laser irradiation position Lb from the position Pb2 to the imaginary straight line Sv2 in the Y direction after moving the laser irradiation position Lb from the imaginary straight line Sv1 to the position Pb2 in the Y direction in the switching period Tc is not limited to the example of Fig. 15C and movement is restricted to the Fig. 15D, Fig. 15E and Fig. 15F can be performed in the manner shown.

[0146] Fig. 15D shows diagrams schematically showing a fourth example of the process carried out according to the flowchart of Fig. 14 is carried out, Fig. 15E shows diagrams schematically showing a fifth example of the process performed according to the flowchart of Fig. 14 is carried out and Fig. 15F shows diagrams schematically showing a sixth example of the process carried out according to the flowchart of Fig. 14. The designations in the Fig. 15D to 15F are similar to those in Fig. 15C. Fig. 15D to 15F differ from Fig. 15C by a movement mode of the laser irradiation position Lb in the switching period Tc. Accordingly, the following description focuses on the differences from Fig. 15C, and common operating parts are designated by corresponding reference numerals, and the description is omitted where appropriate.

[0147] In the Fig. In the fourth example shown in Fig. 15D, the laser irradiation position Lb starts moving in the Y direction from the imaginary straight line Sv1 to the position Pb2 at the beginning of the deceleration period Td, reaches the position Pb2, and stops at the position Pb2 in the Y direction (i.e., the speed Vy is zero) before the end of the deceleration period Td. However, after the laser irradiation position Lb reaches the position Pb2 in the Y direction, the deceleration period Td continues, and the laser irradiation position Lb continues moving in the X direction. Further, after the start of the acceleration period Ta, the laser irradiation position Lb starts moving in the Y direction from the position Pb2 to the imaginary straight line Sv2 and reaches the imaginary straight line Sv2 at the end of the acceleration period Ta.This means that in a period ΔTy from the middle of the deceleration period Td to the middle of the acceleration period Ta, the laser irradiation position Lb in the Y direction is stopped (ie, the speed Vy is zero).

[0148] In the fifth, in Fig. In the example shown in Figure 15E, the laser irradiation position Lb starts moving in the Y direction from the imaginary straight line Sv1 to the position Pb2 at the beginning of the deceleration period Td, reaches the position Pb2, and stops at the position Pb2 in the Y direction (i.e., the speed Vy is zero) before the end of the deceleration period Td. However, after the laser irradiation position Lb reaches the position Pb2 in the Y direction, the deceleration period Td continues, and the laser irradiation position Lb continues moving in the X direction. In addition, the laser irradiation position Lb starts moving in the Y direction from the position Pb2 to the imaginary straight line Sv2 at the beginning of the acceleration period Ta, and reaches the imaginary straight line Sv2 at the end of the acceleration period Ta.This means that the laser irradiation position Lb is stopped in a period ΔTy from the middle of the deceleration period Td to the beginning of the acceleration period Ta in the Y direction (ie, the speed Vy is zero).

[0149] In the fifth, in Fig. In the example shown in Fig. 15F, the laser irradiation position Lb begins to move in the Y direction from the imaginary straight line Sv1 to the position Pb2 simultaneously with the start of the delay period Td. However, the laser irradiation position Lb has not yet reached the position Pb2 in the Y direction at the end point of the delay time Td. Note that at the end point of the delay period Td, the position (i.e., X coordinate) of the laser irradiation position Lb and the position (i.e., X coordinate) of the position Pb2 in the X direction coincide. Accordingly, the laser irradiation position Lb continues to move toward the position Pb2 in the Y direction even after the end of the delay period Ta. In addition, the laser irradiation position Lb is stopped in the X direction (ie, the speed Vx is zero), while the laser irradiation position Lb moves toward the position Pb2 in the Y direction after the end of the delay period Td.The acceleration period Ta is started, and the laser irradiation position Lb begins to move in the Y direction from the position Pb2 to the imaginary straight line Sv2 as soon as the laser irradiation position Lb reaches the position Pb2. Furthermore, the laser irradiation position Lb reaches the imaginary straight line Sv2 at the same time as the end of the acceleration period Ta.

[0150] Fig. Figure 15G schematically shows a seventh example of a process performed according to the flowchart of Fig. 14. The notation in Fig. 15G is similar to the Fig. 15A. Also in Fig. 15G, the laser processing is carried out sequentially for the planned dividing lines S1, S2, S3 according to the flow chart of Fig. 14 as in Fig. 15A. However, Fig. 15G from Fig. 15A by the process in the switching period Tc for changing the planned parting line S to be laser machined. Accordingly, the following description focuses on the differences from Fig. 15A, and common operating parts are designated by corresponding reference numerals, and the description is omitted where appropriate.

[0151] When the laser irradiation position Lb passes the planned parting line S1 toward the (+X) side, once the laser processing for the planned parting line S1 is completed, the laser irradiation position Lb begins to decelerate toward the (+X) side in the X direction (step S1005) and stops at a position Pb2 on the (+X) side of the semiconductor substrate W in the X direction (step S1006). This position Pb2 is located outside a zone between the imaginary straight line Sv1 and the imaginary straight line Sv2 (on a side opposite the imaginary straight line Sv1 with respect to the imaginary straight line Sv2) in the Y direction. That is, in steps S1005 to S1006, the laser irradiation position Lb moves in the Y direction from the imaginary straight line Sv1 to the position Pb2 beyond the imaginary straight line Sv2, parallel to the deceleration in the X direction.When the laser irradiation position Lb is stopped at position Pb2, the imaging area Ri of the imaging part 8B stops at a position including at least one imaging point Pw(S3). Accordingly, in step S1006, the control unit 100 causes the imaging part 8B to image the imaging area Ri and acquire an image including the imaging point Pw(S3). In this way, the control unit 100 can acquire the image showing the position of the unprocessed planned dividing line S3.

[0152] Subsequently, the laser irradiation position Lb, which was stopped at the position Pb2, begins to accelerate in the X direction toward the (-X) side (step S1001). When the speed Vx of the laser irradiation position Lb increases to the machining speed Vxd by the time the laser irradiation position Lb reaches the end of the semiconductor substrate W on the (+X) side, the laser irradiation position Lb moves toward the (-X) side in the X direction at the constant machining speed Vxd (step S1002). Further, in a period between the start of the acceleration and the start of the constant movement, the laser irradiation position Lb moves at the machining speed Vxd in the Y direction from the position Pb2 to the imaginary straight line Sv2.This means that in steps S1001 to S1002, the laser irradiation position Lb moves in the Y direction from the position Pb2 to the imaginary straight line Sv2 parallel to the acceleration in the X direction. Thus, the laser irradiation position Lb reaches the planned dividing line S2, and line processing for the planned dividing line S2 can be started.

[0153] When the laser irradiation position Lb passes the planned dividing line S2 toward the (-X) side, once the laser processing for the planned dividing line S2 is completed, the laser irradiation position Lb begins to decelerate toward the (-X) side in the X direction (step S1005) and stops at a position Pb3 on the (-X) side of the semiconductor substrate W in the X direction (step S1006). This position Pb3 is provided outside a zone between the imaginary straight line Sv2 and the imaginary straight line Sv3 (on a side opposite the imaginary straight line Sv2 with respect to the imaginary straight line Sv3) in the Y direction. This means that in steps S1005 to S1006, the laser irradiation position Lb moves in the Y direction from the imaginary straight line Sv2 to the position Pb2 beyond the imaginary straight line Sv3, parallel to the deceleration in the X direction.When the laser irradiation position Lb is stopped at position Pb3, the imaging area Ri of the imaging part 8A stops at a position including at least one imaging point Pw(S4). Accordingly, in step S1006, the control unit 100 causes the imaging part 8A to image the imaging area Ri and acquire an image including the imaging point Pw(S4). In this way, the control unit 100 can acquire the image showing the position of an unprocessed planned dividing line S4.

[0154] Next, a speed change of the laser irradiation position Lb is expressed by referring to a “speed change in the X direction” and “speed change in the Y direction” in Fig. 15G. In a line processing period Ts1 (steps S1002 to S1004) during which the line processing of moving the laser beam B toward the (+X) side along the scheduled dividing line S1 is performed, the laser irradiation position Lb does not move in the Y direction while moving in the X direction at the constant processing speed Vxd. Further, in a line processing period Ts2 (steps S1002 to S1004) during which the line processing of moving the laser beam B toward the (-X) side along the scheduled dividing line S2 is performed, the laser irradiation position Lb does not move in the Y direction while moving in the X direction at the constant processing speed Vxd.

[0155] Furthermore, in a switching period Tc (steps S1005, S1006, and S1001) in which the line processing period Ts1 is switched to the line processing period Ts2, the laser irradiation position Lb is moved in the Y direction (feed direction) from the imaginary straight line Sv1 to the imaginary straight line Sv2, in parallel with performing the reverse travel in the X direction as in the above-mentioned case. Specifically, this movement of the laser irradiation position Lb is performed via the position Pb2, which is outside the zone between the imaginary straight line Sv1 and the imaginary straight line Sv2 in the Y direction.This means that the laser irradiation position Lb moves in the Y direction from the imaginary straight line Sv1 to the position Pb2 beyond the imaginary straight line Sv2 in a deceleration period Td, outside the deceleration period Td and an acceleration period Ta included in the switching period Tc, and moves in the Y direction from the position Pb2 to the imaginary straight line Sv2 in the acceleration period Ta. Specifically, the laser irradiation position Lb starts moving from the imaginary straight line Sv1 to the position Pb2 at the same time as the start of the deceleration period Td and reaches the position Pb2 at the same time as the end of the deceleration period Td. Furthermore, the laser irradiation position Lb starts moving from the position Pb2 to the imaginary straight line Sv2 at the same time as the start of the acceleration period Ta and reaches the imaginary straight line Sv2 at the same time as the end of the acceleration period Ta.

[0156] Further, in a stop period Tt provided en route during a transition from the acceleration period Ta to the deceleration period Td, both the speed Vx of the laser irradiation position Lb in the X direction and its speed Vy in the Y direction become zero, and the laser irradiation position Lb is stopped at the position Pb2 with respect to the semiconductor substrate W. In this stop period Tt, the imaging areas Ri of the imaging parts 8A, 8B are also stopped with respect to the semiconductor substrate W. Specifically, the imaging area Ri of the imaging part 8B is located on the (-X) side of the laser irradiation position Lb, which is located on the (+X) side of the semiconductor substrate W, and overlaps the semiconductor substrate W. Accordingly, the infrared camera 81 of the imaging part 8B images a part of the semiconductor substrate W that overlaps the imaging area Ri in the stop period Tt (step S1006).

[0157] In the above example, the position Pb2 is provided on the side opposite the imaginary straight line Sv1 with respect to the imaginary straight line Sv2 in the Y direction. However, the position Pb2 can also be provided on a side opposite the imaginary straight line Sv2 with respect to the imaginary straight line Sv1 in the Y direction. In this case, the laser irradiation position Lb moves from the imaginary straight line Sv1 to the position Pb2 in the deceleration period Td in the Y direction, and from the position Pb2 to the imaginary straight line Sv2 beyond the imaginary straight line Sv1 in the acceleration period Ta in the Y direction. A similar change can also be made for the position Pb3.

[0158] Fig. 16 is a flowchart showing a first application example of line processing for each planned dividing line, and Fig. 17 is a diagram schematically showing an example of a process carried out according to the flowchart of Fig. 16. The designations in Fig. 17 are similar to the Fig. 15A to 15G. The example of Fig. 16 differs from the example of Fig. 14 by the presence of step S1008 of imaging the semiconductor substrate W during line processing, but the other steps S1001 to S1007 are the same. Accordingly, in the example of Fig. 16 everyone who Fig. 15A to 15G (first example to seventh example) are performed. It is noted that although a trace of the laser irradiation position Lb in the switching period Tc in Fig. 17 is not shown, the laser irradiation position Lb is along the axis shown in one of the Fig. 15A to 15G shown track.

[0159] The step S1008 of Fig. 16 is performed as follows. That is, the semiconductor substrate W is imaged while the laser irradiation position Lb is moving along the planned dividing line S1 (step S1008). Specifically, the imaging area Ri (i.e., the imaging area Ri of the imaging part 8A) located on a moving side (i.e., the (+X) side) toward which the laser irradiation position Lb is moving is imaged with respect to the laser irradiation position Lb moving to the (+X) side. In this way, an image is obtained including an imaging point Pw(S11) on the moving side of the laser irradiation position Lb with respect to the laser irradiation position Lb. In this way, an image showing the position of an unprocessed part from the planned dividing line S1 that is currently being line-processed can be obtained.

[0160] This means that in a period in which steps S1003, S1108 and S1104 are performed, the image of the unprocessed part of the planned dividing line S1 to be line-processed is taken in parallel with performing the line processing for the planned dividing line S1.

[0161] Further, the semiconductor substrate W is imaged while the laser irradiation position Lb is moving along the planned dividing line S2 (step S1008). Specifically, the imaging area Ri (i.e., the imaging area Ri of the imaging part 8B) located on a moving side (i.e., the (-X) side) toward which the laser irradiation position Lb is moving is imaged with respect to the laser irradiation position Lb moving to the (-X) side. In this way, an image is obtained including an imaging point Pw(S21) on the moving side of the laser irradiation position Lb with respect to the laser irradiation position Lb. In this way, an image showing the position of an unprocessed part from the planned dividing line S2 that is currently being line-processed can be obtained.

[0162] This means that during the period in which steps S1003, S1108 and S1104 are performed, the image of the unprocessed part of the planned dividing line S2 to be line-processed is taken in parallel with performing the line processing for the planned dividing line S2.

[0163] Further, the semiconductor substrate W is imaged while the laser irradiation position Lb is moving along the planned dividing line S3 (step S1008). Specifically, the imaging area Ri (i.e., the imaging area Ri of the imaging part 8A) located on a moving side (i.e., the (+X) side) toward which the laser irradiation position Lb is moving is imaged with respect to the laser irradiation position Lb moving to the (+X) side. In this way, an image is obtained including an imaging point Pw(S31) on the moving side of the laser irradiation position Lb with respect to the laser irradiation position Lb. In this way, an image showing the position of an unprocessed part from the planned dividing line S3 that is currently being line-processed can be obtained.

[0164] This means that during the period in which steps S1003, S1108 and S1104 are performed, the image of the unmachined part from the planned dividing line S3 to be line machined is taken in parallel with performing the line machining for the planned dividing line S3.

[0165] Steps S1001 to S1007 are repeated until it is confirmed that the line machining for the plurality of planned division lines S (S1, S2, S3, ...) parallel to the X direction is completed ("YES" in step S1007).

[0166] Fig. 18 is a flowchart showing a second application example of line processing for each planned dividing line, and Fig. 19A shows diagrams schematically showing a first example of a process performed according to the flowchart of Fig. 18 is carried out. In Fig. In FIG. 19A, a track of the laser irradiation position Lb moving relative to the semiconductor substrate W is represented by a dotted line, and the imaginary straight lines Sv1, Sv2, Sv3 extending parallel to the X direction along the planned dividing lines S1, S2, S3 between both outer sides of the planned dividing lines S1, S2, S3 are represented by a single-dot chain line. Note that dotted lines representing the track of the laser irradiation position Lb are preferably shown in parts where the track of the laser irradiation position Lb and the imaginary straight lines Sv1, Sv2, Sv3 intersect.

[0167] In the Fig. 19A, the flowchart of Fig. 18 is started from a state in which the laser irradiation position Lb is stopped at a position Pb1 on the (-X) side of the semiconductor substrate W in the X direction. This position Pb1 is a position provided on the imaginary straight line Sv1 along the planned dividing line S1, in other words, facing the planned dividing line S1 from the X direction. The position of the laser irradiation position Lb when the flowchart of Fig. 18 is started, but is not limited to this example and can be modified as appropriate.

[0168] In step S1101, the laser irradiation position Lb stopped at position Pb1 begins to accelerate in the X direction toward the (+X) side and moves parallel to the X direction. Thus, the laser irradiation position Lb moves toward the (+X) side along the imaginary straight line Sv1. When the speed Vx of the laser irradiation position Lb increases to the machining speed Vxd by the time the laser irradiation position Lb reaches the end of the semiconductor substrate W on the (-X) side, the laser irradiation position Lb moves toward the (+X) side at the constant machining speed Vxd in the X direction (step S1102).

[0169] Further, the laser light source 72 is turned on, and the irradiation of the laser beam B onto the laser irradiation position Lb of the machining head 71 is started according to a timing at which the laser irradiation position Lb reaches the end of the semiconductor substrate W on the (-X) side (step S1103). Thus, the laser beam B is irradiated onto the laser irradiation position Lb moving toward the (+X) side in the X direction along the planned dividing line S1, thereby machining the planned dividing line S1 (line machining).

[0170] Furthermore, in this example, the semiconductor substrate W is imaged while the laser irradiation position Lb is moving along the planned dividing line S1 (step S1104). Specifically, the imaging area Ri (i.e., the imaging area Ri of the imaging part 8A) located on a moving side (i.e., the (+X) side) toward which the laser irradiation position Lb is moving is imaged with respect to the laser irradiation position Lb moving to the (+X) side. In this way, an image including an imaging point Pw(S11) on the moving side of the laser irradiation position Lb with respect to the laser irradiation position Lb is obtained. In this way, an image showing the position of an unprocessed part from the planned dividing line S1 that is currently being line-processed can be obtained.

[0171] Then, the laser light source 72 is turned off, and the irradiation of the laser beam B onto the laser irradiation position Lb from the machining head 71 is stopped according to a timing at which the laser irradiation position Lb reaches the end of the semiconductor substrate W on the (+X) side (step S1105). Thus, in a period from step S1103 to step S1105, the image of the unmachined part from the planned dividing line S1 to be machined is captured in parallel with the line machining for the planned dividing line S1.

[0172] When the laser irradiation position Lb passes the planned dividing line S1 toward the (+X) side, the laser irradiation position Lb begins to decelerate toward the (+X) side in the X direction (step S1106). In step S1107, it is confirmed whether or not laser processing is completed for the plurality of planned dividing lines S parallel to the X direction. If there is an unprocessed planned dividing line S among these planned dividing lines S ("NO" in step S1107), the process returns to step S1101.

[0173] As a result, the laser irradiation position Lb is accelerated in the X direction toward the (-X) side (step S1101) after the X-direction speed Vx of the laser irradiation position Lb decelerated toward the (+X) side becomes zero in the X direction. When the speed Vx of the laser irradiation position Lb increases to the machining speed Vxd by the time the laser irradiation position Lb reaches the end of the semiconductor substrate W on the (+X) side, the laser irradiation position Lb moves toward the (-X) side in the X direction at the constant machining speed Vxd (step S1102).

[0174] As just described, in the example of the Fig. 18 and Fig. 19A, the reverse drive in the X direction as in the above-mentioned case. Parallel to this reverse drive, the laser irradiation position Lb moves in the Y direction from the imaginary straight line Sv1 to the imaginary straight line Sv2. In this way, the laser irradiation position Lb reaches the planned parting line S2 by moving in the Y direction to the imaginary straight line Sv2 as soon as the speed Vx in the X direction of the laser irradiation position Lb increases to the machining speed Vxd.

[0175] However, in this example, a movement mode in the Y direction of the laser irradiation position Lb is different from the one mentioned above. That is, the laser irradiation position Lb continuously moves in the Y direction from a scheduled dividing line Sb1 to a scheduled dividing line Sb2 (continuous feed drive), in parallel with the reverse drive for decelerating, stopping, and accelerating the laser irradiation position Lb in the X direction. Specifically, the continuous feed drive of the laser irradiation position Lb in the Y direction is performed during the entire time before and after the time when the speed Vx of the laser irradiation position Lb in the X direction becomes zero due to the reverse drive. Therefore, in this example, there is no time when both the speed Vx in the X direction of the laser irradiation position Lb and its speed Vy in the Y direction become zero.

[0176] The laser light source 72 is turned on, and the irradiation of the laser beam B to the laser irradiation position Lb from the machining head 71 is started according to a timing at which the laser irradiation position Lb reaches the end of the semiconductor substrate W on the (+X) side (step S1103). Thus, the laser beam B is irradiated to the laser irradiation position Lb moving toward the (-X) side in the X direction along the planned dividing line S2, and the planned dividing line S2 is machined (line machining).

[0177] Furthermore, in this example, the semiconductor substrate W is imaged while the laser irradiation position Lb is moving along the planned dividing line S2 (step S1104). Specifically, the imaging area Ri (i.e., the imaging area Ri of the imaging part 8B) located on a moving side (i.e., the (-X) side) toward which the laser irradiation position Lb is moving is imaged with respect to the laser irradiation position Lb moving to the (-X) side. In this way, an image including an imaging point Pw (S21) on the moving side of the laser irradiation position Lb with respect to the laser irradiation position Lb is obtained. In this way, an image showing the position of an unprocessed part from the planned dividing line S2 that is currently being line-processed can be obtained.

[0178] The laser light source 72 is turned off, and the irradiation of the laser beam B onto the laser irradiation position Lb from the machining head 71 is terminated according to a timing at which the laser irradiation position Lb reaches the end of the semiconductor substrate W on the (-X) side (step S1105). Thus, in a period from step S1103 to step S1105, the image of the unmachined part from the planned dividing line S2 to be line-machined is captured in parallel with the line machining for the planned dividing line S2.

[0179] When the laser irradiation position Lb passes the planned dividing line S2 toward the (-X) side, the laser irradiation position Lb begins to decelerate toward the (-X) side in the X direction (step S1106). In step S1107, it is confirmed whether or not the line processing for the plurality of planned dividing lines S parallel to the X direction is completed. If there is any unprocessed planned dividing line S among these planned dividing lines S ("NO" in step S1107), the process returns to step S1101.

[0180] As a result, after the X-direction speed Vx of the laser irradiation position Lb decelerated toward the (-X) side becomes zero in the X direction, the laser irradiation position Lb accelerates in the X direction toward the (+X) side (step S1101). When the speed Vx of the laser irradiation position Lb increases to the machining speed Vxd by the time the laser irradiation position Lb reaches the end of the semiconductor substrate W on the (-X) side, the laser irradiation position Lb moves toward the (+X) side in the X direction at the constant machining speed Vxd (step S1102).

[0181] At this time, as in the above case, the continuous feed drive in the Y direction for the laser irradiation position Lb is performed in parallel with the reverse drive in the X direction. Thus, the laser irradiation position Lb reaches the planned parting line S3 by moving in the Y direction along the imaginary straight line Sv3 when the speed Vx in the X direction of the laser irradiation position Lb increases to the machining speed Vxd.

[0182] The laser light source 72 is turned on, and irradiation of the laser beam B to the laser irradiation position Lb from the machining head 71 is started according to a timing at which the laser irradiation position Lb reaches the end of the semiconductor substrate W on the (-X) side (step S1103). Thus, the laser beam B is irradiated to the laser irradiation position Lb moving toward the (+X) side in the X direction along the planned dividing line S3, and the planned dividing line S3 is machined (line machining).

[0183] Furthermore, in this example, the semiconductor substrate W is imaged while the laser irradiation position Lb is moving along the planned dividing line S3 (step S1104). Specifically, the imaging area Ri (i.e., the imaging area Ri of the imaging part 8A) located on a moving side (i.e., the (+X) side) toward which the laser irradiation position Lb is moving is imaged with respect to the laser irradiation position Lb moving to the (+X) side. In this way, an image including an imaging point Pw (S31) on the moving side of the laser irradiation position Lb with respect to the laser irradiation position Lb is obtained. In this way, an image showing the position of an unprocessed part from the planned dividing line S3 that is currently being line-processed can be obtained.

[0184] Then, the laser light source 72 is turned off, and the irradiation of the laser beam B onto the laser irradiation position Lb from the machining head 71 is stopped according to a timing at which the laser irradiation position Lb reaches the end of the semiconductor substrate W on the (+X) side (step S1105). Thus, in a period from step S1103 to step S1105, the image of the unmachined part from the planned dividing line S3 to be machined is captured in parallel with the line machining for the planned dividing line S3.

[0185] Next, a speed change of the laser irradiation position Lb is expressed by referring to a “speed change in the X direction” and a “speed change in the Y direction” in Fig. 19A. In a line machining period Ts1 (steps S1103 to S1105) during which the line machining of moving the laser beam B toward the (+X) side along the scheduled dividing line S1 is performed, the laser irradiation position Lb does not move in the Y direction while moving in the X direction at the constant machining speed Vxd. Further, in a line machining period Ts2 (steps S1103 to S1105) during which the line machining of moving the laser beam B toward the (-X) side along the scheduled dividing line S2 is performed, the laser irradiation position Lb does not move in the Y direction while moving in the X direction at the constant machining speed Vxd.

[0186] Furthermore, in a switching period Tc (steps S1106, S1101) during which switching occurs from the line machining period Ts1 to the line machining period Ts2, the following operation is performed. That is, the X-axis driver 65 (machining axis driver) performs reverse driving to bring the laser irradiation position Lb to the intended dividing line S2 (second machining line) by accelerating the laser irradiation position Lb toward the (-X) side (step S1101) after decelerating and stopping the laser irradiation position Lb that has passed the intended dividing line S1 (first machining line) toward the (+X) side (first side), and accelerating toward the (+X) side in the X direction (machining direction) (step S1106).In parallel with this reverse drive, the Y-axis driver 63 (feed axis driver) performs the continuous feed drive to move the laser irradiation position Lb in the Y direction (feed direction) from the imaginary straight line Sv1 (first imaginary straight line) extending in the X direction outside the planned dividing line S1, along the planned dividing line S1 to the imaginary straight line Sv2 (second imaginary straight line) extending in the X direction outside the planned dividing line S2, continuously along the planned dividing line S2.

[0187] Specifically, the control unit 100 controls the X-axis driver 65 and the Y-axis driver 63 such that the Y-axis driver 63 starts the continuous feed drive before the X-axis driver 65 stops the laser irradiation position Lb in the X direction by the reverse drive, and the Y-axis driver 63 stops the continuous feed drive after the X-axis driver 65 stops the laser irradiation position Lb in the X direction by the reverse drive. In this way, the Y-axis driver 63 moves the laser irradiation position Lb in the Y direction during the entire period before and after the time when the movement of the laser irradiation position Lb in the X direction is stopped due to the reverse drive (in other words, in a period when the X-axis driver 65 stops the laser irradiation position Lb in the X direction by the reverse drive).

[0188] In other words, the switching period Tc includes a deceleration period Td (step S1006) for decelerating the laser irradiation position Lb in the X direction and an acceleration period Ta (step S1001) for accelerating the laser irradiation position Lb in the X direction. In contrast, the Y-axis driver 63 continuously performs the movement of the laser irradiation position Lb in the Y direction (i.e., it performs the movement without stopping the laser irradiation position Lb in the Y direction) during the entire time before and after the time in which a transition period Tx from the deceleration period Td to the acceleration period Ta takes place. Note that the laser irradiation position Lb is stopped in the X direction (i.e., the speed Vx is zero) during the transition period Tx.

[0189] Fig. 19B shows diagrams schematically showing a second example of the process according to the flowchart of Fig. 18 represent the process carried out. Fig. 19B differs from Fig. 19A by the number of imaging processes of the semiconductor substrate W parallel to the line processing. This means that in the example of the Fig. 19B, the imaging area Ri (i.e., the imaging area Ri of the imaging part 8A) located on a moving side (i.e., the (+X) side) toward which the laser irradiation position Lb is moving, with respect to the laser irradiation position Lb moving toward the (+X) side to perform line processing for the scheduled dividing line S1, is imaged a plurality of times (twice in this example) (step S1104). In this way, two images each having two pixels Pw(S11), Pw(S12) on the moving side of the laser irradiation position Lb with respect to the laser irradiation position Lb are obtained. In this way, images showing the positions of the unprocessed parts from the scheduled dividing line S1 that is currently being line processed can be obtained.

[0190] Similarly, the imaging area Ri (i.e., the imaging area Ri of the imaging part 8B) located on a moving side (i.e., the (-X) side) toward which the laser irradiation position Lb is moving is imaged multiple times (twice in this example) (step S1104). In this way, two images each having two pixels Pw(S21), Pw(S22) on the moving side of the laser irradiation position Lb with respect to the laser irradiation position Lb are obtained. In this way, images showing the positions of the unprocessed parts from the planned dividing line S2 that is currently being line-machined can be obtained. Furthermore, imaging is also performed multiple times during the line processing for the planned dividing line S3 (step S1104).

[0191] Fig. Fig. 20 is a diagram schematically showing an example of an image of the semiconductor substrate obtained in step S1008 of the Fig. 16 or step S1104 of the Fig. 18 is obtained. In the above examples, a region including an intersection point of two planned, mutually orthogonal dividing lines S is imaged to obtain an image IM. Since the image IM is acquired while the imaging region Ri is moved in the X direction with respect to the semiconductor substrate W, a luminance in the X direction is averaged in the image IM. As a result, a high luminance region extending parallel to the X direction according to the planned dividing line S and low luminance regions having a luminance lower than the high luminance region and extending parallel to the X direction according to the semiconductor chips C appear. Specifically, in the Y direction, the high luminance region is enclosed by two low luminance regions.Therefore, the control unit 100 can confirm the position of the scheduled dividing line S in the Y direction based on the high luminance area corresponding to the scheduled dividing line S.

[0192] In the embodiment described above using the Fig. 16 to 20, the image of the part of the semiconductor substrate W overlapping the imaging range Ri is obtained by imaging the imaging range Ri that extends during the execution of the line processing (steps S1003 to S1004, S1103 to S1105) of machining the planned dividing line S by irradiating the laser beam B to the laser irradiation position Lb while moving the laser irradiation position Lb along the planned dividing line S (steps S1008, S1104). This means that the execution time of the line processing is effectively utilized to image the semiconductor substrate W. In this way, the semiconductor substrate W can be efficiently imaged in the laser processing technique for machining the planned dividing line S by irradiating the planned dividing line S with the laser beam B.

[0193] Furthermore, the imaging part 8 images the imaging area Ri provided on a downstream side in the moving direction of the laser irradiation position Lb with respect to the planned parting line S in the line processing (steps S1003 to S1004, S1103 to S1105). In such a configuration, an image of an unprocessed side of the position processed by the laser beam B (ie, the laser irradiation position Lb) can be obtained. Therefore, the control unit 100 can detect an influence of the processing by the laser beam B on the unprocessed part of the semiconductor substrate W based on this image.

[0194] In the example of Fig. 19B, the imaging part 8 images the imaging area Ri multiple times in a period in which the line processing (steps S1003 to S1004, S1103 to S1105) is performed once (steps S1008, S1104). With such a configuration, multiple images of the semiconductor substrate W can be obtained, effectively utilizing the execution time of the line processing.

[0195] In the in the Fig. 18, Fig. 19A and Fig. 19B, the line processing (first line processing) of processing the planned dividing line S1 (first processing line) and the line processing (second line processing) of processing the planned dividing line S2 (second processing line) are alternately performed by using the X-axis driver 65 for relatively moving the laser irradiation position Lb in the X direction with respect to the semiconductor substrate W and the Y-axis driver 63 (feed axis driver) for relatively moving the laser irradiation position Lb in the Y direction with respect to the semiconductor substrate W.Furthermore, in the switching period Tc between the line processing for the planned dividing line S1 and the line processing for the planned dividing line S2, the X-axis driver 65 and the Y-axis driver 63 perform the following operation to move the laser irradiation position Lb that has passed through the planned dividing line S1 toward the planned dividing line S2. That is, the X-axis driver 65 performs the backward movement to move the laser irradiation position Lb to the planned dividing line S2 by accelerating the laser irradiation position Lb toward the (-X) side after the laser irradiation position Lb that has passed through the planned dividing line S1 toward the (+X) side is decelerated and stopped in the X direction toward the (+X) side.Further, the Y-axis driver 63 moves the laser irradiation position Lb in the Y direction from the imaginary straight line Sv1 extended in the X direction outside the planned dividing line S1 along the planned dividing line S1 to the imaginary straight line Sv2 extended in the X direction outside the planned dividing line S2 along the planned dividing line S2.

[0196] Specifically, the Y-axis driver 63 performs continuous feed driving to continuously move the laser irradiation position Lb in the Y direction from the imaginary straight line Sv1 to the imaginary straight line Sv2 in the switching period Tc. Then, the control unit 100 controls the X-axis driver 65 and the Y-axis driver 63 so that the Y-axis driver 63 starts the continuous feed driving before the X-axis driver 65 stops the laser irradiation position Lb by reverse driving, and the Y-axis driver 63 stops the continuous feed driving after the X-axis driver 65 stops the laser irradiation position Lb by reverse driving.This means that the Y-axis driver 63 moves the laser irradiation position Lb in the Y direction before and after the time at which movement of the laser irradiation position Lb in the X direction is stopped due to the reverse drive (in other words, during a period in which the X-axis driver 65 stops the laser irradiation position Lb due to the reverse drive). As described above, in the switching period Tc, both a period of deceleration of the laser processing position Lb in the (+X) direction in the X direction and a period of acceleration of the laser irradiation position Lb in the (-X) direction in the X direction are effectively utilized to move the laser irradiation position Lb in the Y direction. This makes it possible to suppress the influence of the switching period Tc of switching the movement direction of the laser beam B on the time required to completely process the semiconductor substrate W.In addition, since the execution time of the line processing is effectively utilized to image the semiconductor substrate W as described above, it is possible to suppress the time for switching the scheduled dividing line S for the line processing, efficiently image the semiconductor substrate W, and quickly complete the processing of the semiconductor substrate W.

[0197] Furthermore, the mapping part 8 maps the mapping area Ri, which includes at least the planned dividing line S, during the execution of the line processing ( Fig. 20). A part corresponding to the planned dividing line S appears to extend in the X direction due to the contrast between both sides of the planned dividing line S and the planned dividing line S in the Y direction in an image IM obtained by such imaging. Therefore, the control unit 100 can accurately detect an influence of laser processing on the position of the planned dividing line S in the Y direction based on the position of this part in the Y direction.

[0198] Fig. 21 is a flowchart showing an example of a laser machining condition determination method in line machining, Fig. 22A shows diagrams showing parameters related to the determination of laser processing conditions, Fig. 22B is a diagram showing a temporal influence of the laser processing condition, and Fig. 22C is a table showing an example of a table referred to in the laser processing condition determination of Fig. 21. This table is stored in advance in memory 190.

[0199] Fig. 22A shows an upper diagram showing the relationship between the speed Vx of the laser irradiation position Lb moving in the X direction and time, and a lower diagram showing the relationship between the speed Vx of the laser irradiation position Lb moving in the X direction and the position in the X direction (ie, the X coordinate) of the laser irradiation position Lb in line processing.

[0200] As shown in the diagram below, to perform line machining for the planned dividing line S, irradiation position scanning is performed to irradiate the laser beam B to the laser irradiation position Lb overlapping the planned dividing line S while moving the laser irradiation position Lb in the X direction from a start point Xs on one side of the planned dividing line S to an end point Xe on the other side (the side opposite to one side) of the planned dividing line S. That is, in the irradiation position scanning, the laser beam B is irradiated from the machining head 71 to the laser irradiation position Lb overlapping the planned dividing line S while moving the laser irradiation position Lb in the X direction from the start point Xs to the end point Xe by the X-axis driver 65. In this way, according to the irradiation position scanning, the aforementioned line machining is performed.

[0201] In this irradiation position scanning, a constant speed zone SC is set for the planned division line S. This constant speed zone SC is located between the start point Xs and the end point Xe in the X direction and is set to include the planned division line S. In this example, both ends of the constant speed zone SC coincide with both ends of the planned division line S in the X direction, in other words, the constant speed zone SC coincides with the planned division line S. However, a setting mode of the constant speed zone SC is not limited to this example, and the constant speed zone SC can be set by adding offsets outside the two ends of the planned division line S. In this case, the constant speed zone SC becomes longer than the planned division line S.The length of the offset can be a predetermined fixed value or a value obtained by multiplying the length of the planned dividing line S by a predetermined scale factor (e.g., 1%). The length of such a constant speed zone SC is determined according to the length of the planned dividing line S. The longer the planned dividing line S, the longer the constant speed zone SC (in other words, the shorter the planned dividing line S, the shorter the constant speed zone SC).

[0202] In this irradiation position scanning, the laser irradiation position Lb moves in the X direction from the start point Xs located on one side of the constant speed zone SC to the end point X3 located on the other side of the constant speed zone SC. Furthermore, in the acceleration period Ta during which the laser irradiation position Lb moves in the X direction from the start point Xs to an end point Xss on one side of the constant speed zone SC in the X direction, the laser irradiation position Lb is accelerated at an acceleration A in the X direction, and the X-direction speed Vx of the laser irradiation position Lb increases from zero to the machining speed Vxd.Furthermore, in a constant speed period Tsc (which coincides with the line processing period Ts in this example), the laser irradiation position Lb moves in the X direction from the end Xss on one side of the constant speed zone SC to an end Xse on the other side of the constant speed zone SC at the constant processing speed Vxd in the X direction. Furthermore, in the deceleration period Tb during which the laser irradiation position Lb moves in the X direction from the end Xse on the other side of the constant speed zone SC to the end point Xe, the laser irradiation position Lb is decelerated at the acceleration A in the X direction, and the speed Vx in the X direction of the laser irradiation position Lb decreases from the processing speed Vxd to zero.

[0203] At this time, the acceleration period Ta is a period (Vxd / A) required to increase the speed Vx from zero to the machining speed Vxd at acceleration A; the constant speed period Tsc is a period (Lsc / Vxd) required to move at the machining speed Vxd by a constant speed distance Lsc, which is the length of the constant speed zone SC; and the deceleration period Td is a period (Vxd / A) required to decrease the speed Vx from the machining speed Vxd at acceleration A to zero. Therefore, the scanning time t required for irradiation position scanning is: t=2×Vxd / A+Lsc / Vxd.

[0204] Thus, the Fig. 22B between the machining speed Vxd and the sampling time t is satisfied. This means that the sampling time t has a minimum value when the machining speed Vxd is Vxd_min (= (Lsc×A / 2) 1 / 2 ). Therefore, line machining can be performed efficiently by setting the machining speed Vxd according to the length (constant speed distance Lsc) of the constant speed zone SC.

[0205] However, when the machining speed Vxd is changed, the frequency of the laser beam B emitted from the laser light source 72 must also be changed. In particular, when the machining speed Vxd is increased, the frequency of the laser beam B must be increased. In contrast, the frequency of the laser beam B can only be changed stepwise and not continuously. Accordingly, the table from Fig. 22C is used. This table specifies a relationship between the constant speed distance Lsc (length of the planned parting line S in this example), the machining speed Vxd, and the frequency fc of the laser beam B. Specifically, the table specifies the following laser machining conditions. When the constant speed distance Lsc is less than or equal to Lsc(1), the machining speed Vxd is set to Vxd(1) and the frequency of the laser beam B is set to fc(1). When the constant speed distance Lsc is greater than Lsc(1) and less than or equal to Lsc(2), the machining speed Vxd is set to Vxd(2) and the frequency of the laser beam B is set to fc(2).

[0206] This means that in the laser processing condition determination of Fig. 21 the length (constant speed distance Lsc) of the constant speed zone SC defined for the planned dividing line S to be machined is obtained (step S1201). Then, the machining speed Vxd is determined (step S1202) and the frequency fc of the laser beam B is determined (step S1203) based on the constant speed distance Lsc obtained in step S1201 and the table of Fig. 22C. The irradiation position scanning is carried out according to the Fig. 21 laser processing conditions (processing speed Vxd and frequency fc) determined in this way.

[0207] The irradiation position scanning is performed sequentially for the plurality of planned dividing lines S parallel to the X direction. In other words, a plurality of irradiation position scannings different from each other are performed for the planned dividing lines S. In contrast, the laser processing condition determination of Fig. 21 is performed for each of the plurality of irradiation position scans. During each irradiation position scan, the laser irradiation position Lb is moved, and the laser beam B is irradiated according to the laser processing conditions determined for each irradiation position scan.

[0208] Specifically, when the semiconductor substrate W formed with a plurality of scheduled dividing lines S parallel to the X direction is circular as in the above example, the farther the scheduled dividing line S is from a circle center in the Y direction, the shorter it becomes, and the constant speed distance Lsc set for the scheduled dividing line S also becomes shorter. This means that the constant speed distance Lsc set for the irradiation position scanning differs depending on the position of the scheduled dividing line S in the Y direction for which the irradiation position scanning is performed. Accordingly, it is convenient to perform laser processing condition determination for each irradiation position scanning performed sequentially for a plurality of scheduled dividing lines S.

[0209] Note that the laser processing condition determination may be performed at any time before the start of the irradiation position scanning, which is a target of the laser processing condition determination. For example, the laser processing condition determination may be performed for all of the plurality of irradiation position scans before the start of the plurality of irradiation position scans each corresponding to the plurality of planned dividing lines S parallel to the X direction. Alternatively, in the case of performing the next irradiation position scan following one irradiation position scan, the laser processing condition determination for the next irradiation position scan may be performed during the execution of the one irradiation position scan.

[0210] It is noted that, as in Fig. 22C, the machining speed Vxd is adjusted by selecting one of a plurality of discrete machining speeds Vxd(1), Vxd(2), Vxd(3), and Vxd(4), and the oscillation frequency fc is adjusted by selecting one of a plurality of discrete oscillation frequencies fc(1), fc(2), fc(3), and fc(4). This means that in the laser machining condition determination, the machining speed Vxd and the oscillation frequency fc are selected based on which of the Fig. 22C. At this time, if the areas to which the constant speed path Lsc belongs are the same between two consecutive laser irradiation position scans performed when the machining speed Vxd and the oscillation frequency fc are adjusted by performing laser machining condition determination for each of the plurality of irradiation position scans, the machining speed Vxd and the oscillation frequency fc are maintained. On the other hand, if the areas to which the constant speed path Lsc belongs are different between two consecutive laser irradiation position scans, the machining speed Vxd and the oscillation frequency fc are changed (i.e., switched).This means that setting the machining speed Vxd includes maintaining the machining speed Vxd and changing (switching) the machining speed Vxd, and setting the oscillation frequency fc includes maintaining the oscillation frequency fc and changing (switching) the oscillation frequency fc.

[0211] As described above, in the above embodiment, the laser processing device 1 corresponds to an example of a "laser processing device" according to the invention, the clamping stage 3 corresponds to an example of a "support member" according to the invention, the Y-axis driver 63 corresponds to an example of a "feed axis driver" according to the invention, the X-axis driver 65 corresponds to an example of a "processing axis driver" according to the invention, the processing head 71 corresponds to an example of a "processing head" according to the invention, the imaging part 8 corresponds to an example of an "imaging part" according to the invention, the control unit 100 corresponds to an example of a "control unit" according to the invention, the control unit 100 corresponds to an example of a "computer" according to the invention, the laser processing program 191 corresponds to an example of a "laser processing program" according to the invention,the recording medium 192 corresponds to an example of a “recording medium” according to the invention; the laser beam B corresponds to an example of a “laser beam” according to the invention; the laser irradiation position Lb corresponds to an example of a “laser irradiation position” according to the invention; the imaging region Ri corresponds to an example of an “imaging region” according to the invention; the intended dividing line S corresponds to an example of a “processing line” according to the invention; the imaginary straight line Sv corresponds to an example of an “imaginary straight line” according to the invention; the switching period Tc corresponds to an example of a “switching period” according to the invention; the semiconductor substrate W corresponds to an example of a “processing object” according to the invention; the X direction corresponds to an example of a “processing direction” according to the invention; the Y direction corresponds to an example of a “feed direction” according to the invention;and the (+X) side and the (-X) side correspond to examples of a “first side” and a “second side” according to the invention or of the “second side” and the “first side” according to the invention.

[0212] The one in the Fig. The detailed procedure for imaging the imaging areas Ri moving in the X direction according to the execution of the line processing by the infrared camera 81 described in Figs. 16 to 20 can be changed as follows. Fig. Fig. 23 is a schematic plan view showing a positional relationship of the laser irradiation position and the imaging regions in the detailed process of imaging the imaging regions, and Fig. 24 is a schematic plan view showing an imaging object in the detailed process of imaging the imaging area.

[0213] As in Fig. 23, in the plan view, the imaging parts 8 (8A, 8B) and the processing head 71 are arranged in the X direction such that the center points Ric of the imaging regions Ri of the imaging parts 8 (8A, 8B) and a focus (i.e., the laser irradiation position Lb) of the laser beam B irradiated by the processing head 71 are arranged parallel to the X direction. Furthermore, as described above, the imaging region Ri on the downstream side in the moving direction of the laser irradiation position Lb of the two imaging regions Ri is imaged by the infrared camera 81.

[0214] This means that, as in Fig. 24, the laser beam B irradiated onto the laser irradiation position Lb moves in a scanning direction Ds parallel to the X direction, and the imaging region Ri moves in the scanning direction Ds on the downstream side of the laser irradiation position Lb in the scanning direction Ds. Here, a downstream side of the laser irradiation position Lb in the scanning direction Ds is an unprocessed part S_d that has not been processed by the irradiation of the laser beam B, and an upstream side of the laser irradiation position Lb in the scanning direction Ds is a processed part S_u that has been processed by the irradiation of the laser beam B.Therefore, the imaging range Ri on the downstream side of the laser irradiation position Lb in the scanning direction Ds includes the unprocessed part S_d of the planned dividing line S, and the laser processing control computer 120 (control unit) can obtain the image IM of the unprocessed part S_d of the planned dividing line S by imaging this imaging range Ri.

[0215] Specifically, the laser processing control computer 120 causes the infrared camera 81 to perform exposure during a period (intersecting period) in which the planned dividing line S intersects the imaging area Ri on the downstream side (i.e., the unprocessed part S_d) of the laser irradiation position Lb in the scanning direction Ds (sweeping operation). At this time, the intersection of the planned dividing line S with the imaging area Ri indicates that both ends of the planned dividing line S are outside the imaging area Ri, while the planned dividing line S overlaps the imaging area Ri.

[0216] Fig. Figure 25 is a flowchart showing an example of camera exposure control. The flowchart of the Fig. 25 is performed by the laser processing control computer 120, which controls the infrared camera 81 via the camera controller 122A, 122B, and is performed in parallel with the line processing for the planned dividing line S. In step S1301, it is judged whether or not the planned dividing line S (ie, the unprocessed part S_d of the planned dividing line S) has exceeded the imaging range Ri on the downstream side in the scanning direction Ds (occasionally referred to as "downstream imaging range Ri") of the two imaging ranges Ri of the two infrared cameras 81.

[0217] At a time point when the planned dividing line S crosses the downstream imaging area Ri ("YES" in step S1301), the infrared camera 81 imaging the downstream imaging area Ri starts exposure (step S1302). In step S1303, it is judged whether the downstream imaging area Ri has deviated from the unprocessed part S_d of the planned dividing line S or not, that is, is no longer crossed. At a time point when the downstream imaging area Ri deviates from the unprocessed part S_d of the planned dividing line S ("YES" in step S1303), the exposure of the infrared camera 81 imaging this imaging area Ri is stopped (step S1304).

[0218] As described above, the imaging region Ri moving in the scanning direction Ds is imaged by the infrared camera 81 according to a movement of the laser irradiation position Lb. Specifically, the exposure of the infrared camera 81 imaging this imaging region Ri continues during the intersecting period (period of steps S1301 to S303) during which the imaging region Ri intersects the planned dividing line S on the downstream side of the laser irradiation position Lb in the scanning direction Ds. Therefore, the image IM that has accumulated light from the imaging region Ri during the intersecting period (sometimes referred to as "panning the image") is obtained. Specifically, the infrared camera 81 acquires the panning image IM by accumulating light (infrared rays) detected by a built-in solid-state pixel.It is noted that a period during which the exposure continues coincides with the overlap period in this example, but may also be, for example, a period that includes the overlap period and is longer than the overlap period.

[0219] Fig. Figure 26 is a table schematically showing information that can be obtained from panning images captured by the panning process. Fig. 26, the planned division line S, the swivel image IM, which is obtained by imaging the planned division line S with the swivel process, and the information (determination) that can be obtained from the swivel image IM, are linked together and shown for each of the three different alignment states 1 to 3. Furthermore, in Fig. 26, a track J of the laser irradiation position Lb moving relatively in the X direction with respect to the semiconductor substrate W (in other words, a track J of the center Ric of the imaging area Ri) is represented by a dashed line. Specifically, a cumulative line image AI obtained by accumulating the light from the intended dividing line S appears in the image IM, and information is obtained based on this cumulative line image AI.

[0220] In alignment state 1, the planned dividing line S is parallel to the X direction and coincides with the track J. Thus, in the pan image IM, the cumulative line image AI extends parallel to the X direction at a position Yj (Y coordinate) of the track J in the Y direction and has a narrow width (width in the Y direction) and a high luminance. From such a cumulative line image AI, it can be determined that the position of the planned dividing line S is satisfactory.

[0221] In alignment state 2, the planned pitch line S deviates from the track J in the Y direction while being parallel to the X direction. Therefore, in the pan image IM, the cumulative line image AI extends in the X direction at a position Yd that deviates from a position Yj of the track J in the Y direction, and has a narrow width and high luminance. From such a cumulative line image AI, it can be determined that a positional deviation with a deviation amount (Yd-Yj) in the Y direction has occurred between the planned pitch line S and the track J.

[0222] In alignment state 3, the planned division line S is oblique to the X direction. Therefore, the cumulative line image AI has a thick width and a low luminance in the image IM. From such a cumulative line image AI, it can be determined that the planned division line S is inclined with respect to the track J.

[0223] Based on this knowledge, the laser processing control computer 120 makes the Fig. 27 shown determination for the swivel image IM. Fig. 27 is a flowchart showing an example of image determination performed for the pan image, and Fig. Figure 28 is a diagram schematically showing a mask used in image determination of the Fig. 27 is used.

[0224] In step S1401, masking is performed for the panned image IM. A mask M ( Fig. 28) used in the masking is to hide end parts Me on both sides of the panned image IM in the Y direction and extract a center part Mc between these end parts Me. The end parts Me extend parallel to the X direction, and the center part Mc has a rectangular shape. In step S1402, the cumulative line image AI is extracted from the center part Mc in the panned image IM. Specifically, the cumulative line image AI can be extracted by binarizing each pixel value (luminance) of the cumulative line image AI by a predetermined threshold. Furthermore, image processing such as closing and opening can be performed in combination when appropriate.

[0225] In step S1403, it is judged whether the luminance (e.g., an average or median luminance value) of the cumulative line image AI is greater than or equal to a threshold luminance. If the luminance of the cumulative line image AI is greater than or equal to the threshold luminance ("YES" in step S1403), the panned image IM can be estimated to fall under a processing result 1 or 2 from among the alignment states 1 to 3 shown in Fig. 26.

[0226] Accordingly, in step S1404, it is judged whether or not a positional deviation has occurred between the position Yj of the track J and the cumulative line image AI in the Y direction. Specifically, it is judged that no positional deviation has occurred ("NO") when a distance between the position Yj of the track J and the cumulative line image AI in the Y direction is smaller than a threshold distance, while a positional deviation is judged to have occurred (YES) when this distance is equal to or greater than the threshold distance. If no positional deviation has occurred ("NO" in step S1404), it is determined to be satisfactory (step S1405), and the line processing for the semiconductor substrate W continues.

[0227] In contrast, if the positional deviation has occurred ("YES" in step S1404), the position of the planned dividing line S with respect to the track J of the laser irradiation position Lb is corrected in the line processing (positional deviation correction) performed after the line processing performed in parallel with the imaging of the pan image IM. Specifically, the planned dividing line S to be line-machined after the planned dividing line S (imaged planned dividing line S) imaged in the pan image IM and the position of the laser irradiation position Lb in the Y direction are corrected by a positional deviation amount (=Yd-Yj) in the Y direction. After the positional deviation is corrected in this way, the line processing for this planned dividing line S is started.In this way, line machining for this planned dividing line S can be started from the laser irradiation position Lb located at a convenient position in the Y direction. Note that if the position deviation correction is performed too late to perform line machining on the next planned dividing line S after the imaged planned dividing line S, the position deviation correction for the planned dividing line S can be performed to perform line machining on it after the next planned dividing line S.

[0228] If the luminance of the cumulative line image AI is lower than the threshold luminance in step S1403 ("NO" in step S1403), the pan image IM can be estimated to fall under alignment state 3, among the alignment states 1 to 3 shown in Fig. 26. Accordingly, in step S1407, it is judged whether or not the Y-direction width of the cumulative line image AI is smaller than a lower threshold width. If the width of the cumulative line image AI is smaller than the lower limit width ("YES" in step S1407), it is assumed that an abnormality has occurred, which differs from each in Fig. 26. Therefore, the laser processing control computer 120 issues a warning to a user via a display or a buzzer (step S1408).

[0229] On the other hand, if the width of the cumulative line image AI is equal to or greater than the lower threshold width ("NO" in step S1407), the planned dividing line S is judged to be tilted with respect to the track J of the laser irradiation position Lb, as shown in alignment state 3. Accordingly, in step S1409, it is judged whether the Y-direction width of the cumulative line image AI is equal to or greater than an upper limit width. If the width of the cumulative line image AI is equal to or greater than the upper threshold width ("YES" in step S1409), the tilt of the laser irradiation line G is too large. Therefore, the laser processing control computer 120 notifies the user of a tilt error via the display or buzzer (step S1410).

[0230] On the other hand, if the width of the cumulative line image AI is smaller than the upper limit width ("NO" in step S1409), two-point alignment is performed (step S1411). In this two-point alignment, the positions (X coordinates, Y coordinates) of predetermined two points on the semiconductor substrate W are calculated based on a result of imaging these two points by the infrared camera 81. Further, based on the positions of these two points, an angular deviation of the semiconductor substrate W in the q direction is calculated, and based on this angular deviation, a rotation angle of the semiconductor substrate W in the q direction is adjusted. In this way, the planned dividing line S of the semiconductor substrate W is adjusted to be parallel to the X direction.

[0231] As just described, in the above-described modification, the center point Ric of the imaging region Ri of the imaging part 8 and the focus of the laser beam B irradiated onto the laser irradiation position Lb are arranged in the X direction. Therefore, a state immediately before the irradiation of the laser beam B can be accurately captured by the image IM of the imaging region Ri.

[0232] Furthermore, while executing line processing for one planned dividing line S (target line) among the plurality of planned dividing lines S, the imaging part 8 acquires the image IM by full-period imaging (panning) to cause the infrared camera 81 to continue exposure during the period in which the unprocessed part S_d of this one planned dividing line S crosses the imaging area Ri. With such a configuration, the information (cumulative line image AI) can be obtained by accumulating the luminance of the image IM of the imaging area Ri in the X direction.

[0233] In such a panning image, the accumulated luminance may reach a dynamic range of the infrared camera 81 (solid-state pixel), and the luminance of the image IM may be saturated. Accordingly, the imaging part 8 adjusts an illuminance of the light from this imaging part 8 to be irradiated onto the imaging area Ri. Specifically, an illuminance Tc is set so that an exposure time Tc and the illuminance Tc during the panning process satisfy the following relationship for an exposure time T0 and an illuminance L0 in still images for imaging the semiconductor substrate W by the infrared camera 81, with the infrared camera 81 held stationary with respect to the semiconductor substrate W: Lc=T0×L0 / Tc.

[0234] In this way, the luminance saturation of the image IM can be suppressed.

[0235] Furthermore, it is determined whether the laser irradiation position Lb is correct with respect to the planned parting line S or not, based on the panning image IM (entire period imaging) obtained by the panning operation ( Fig. 27). In such a configuration, it can be confirmed based on the pan image IM whether the laser irradiation position Lb is correct or not.

[0236] Furthermore, the laser processing control computer 120 determines whether the laser irradiation position Lb is correct with respect to the planned parting line S based on the central part Mc excluding the two end parts Me in the Y direction (orthogonal direction) outside the sweep image IM. With such a configuration, the suitability of the laser irradiation position Lb can be confirmed while excluding unnecessary information in the two end parts Me in the Y direction of the sweep image IM.

[0237] Further, the laser machining control computer 120 obtains the amount of positional deviation (Yd-Yj) in the Y direction of the laser irradiation position Lb from a planned dividing line S, and corrects the laser irradiation position Lb based on the amount of positional deviation (Yd-Ys) when the line machining is performed after the line machining for the one planned dividing line S (step S1406) when the occurrence of the positional deviation in the Y direction of the laser irradiation position Lb from the one planned dividing line S (target line) is confirmed based on the pan image IM ("YES" in step S1404). In this way, the positional deviation of the laser irradiation position Lb in the Y direction can be corrected, and the line machining can be performed correctly.

[0238] Furthermore, the laser machining control computer 120 performs alignment for tilt correction (step S1411) when the tilt of the track J of the laser irradiation position Lb with respect to a planned dividing line S (target line) is confirmed based on the pan image IM. With such a configuration, line machining can be performed correctly by correcting the tilt of the laser irradiation position Lb with respect to the planned dividing line S.

[0239] It should be noted that the invention is not limited to the above embodiment, and various changes may be made to the aforementioned embodiment without departing from the spirit of the invention. Specifically, the following changes may be made.

[0240] Furthermore, an object to be imaged by the imaging part 8 is not limited to the intersection of the two planned dividing lines S which are orthogonal to each other as shown in the above examples, but may be, for example, an alignment mark or the like attached to the semiconductor chip C.

[0241] Furthermore, the concrete configuration for the relative movement of the laser irradiation position Lb with respect to the semiconductor substrate W is not limited to the XYΘ drive table 6 and may be, for example, a drive mechanism for driving the machining head 71 in the X and Y directions.

[0242] Furthermore, the number of image parts 8 is limited to two and can be, for example, one.

[0243] Furthermore, the individually separated semiconductor chips C can be produced by the laser processing method described above (substrate processing of Fig.11 or the like) are manufactured (semiconductor chip manufacturing method). In this semiconductor chip manufacturing method, a modified layer is formed by performing line processing for the planned dividing lines S of the semiconductor substrate W by the laser processing method described above (laser processing step). Subsequently, each of the plurality of semiconductor chips C is separated by stretching and expanding the tape E holding the semiconductor substrate W (expansion step). LIST OF REFERENCE SYMBOLS 1 laser processing device 3 the clamping platform (support element) 63 Y-axis drivers (feed axis drivers) 65 of the X-axis driver (machining axis driver) 71 machining head 72 Laser light source 8 Illustration section 100 Control unit (computer) 191 laser processing program 192 Recording medium QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] JP 5037082

[0002]

Claims

[1] Laser processing device, comprising: a support member that supports a processing object with a plurality of processing lines running parallel to each other so that the processing lines run parallel to a predetermined processing direction; a processing head that irradiates a laser beam to a predetermined laser irradiation position; a machining axis driver that moves the laser irradiation position in the machining direction relative to the machining object by driving the support member and / or the machining head in the machining direction; a control unit that performs line processing of the processing line by irradiating the laser beam from the processing head to the laser irradiation position while moving the laser irradiation position along the processing line by the processing axis driver; and an imaging part that images a predetermined imaging area that moves relatively with respect to the processing object integrally with the laser irradiation position while the laser irradiation position moves relative to the processing object; wherein the imaging part acquires an image of a part of the processing object that overlaps the imaging area by imaging the imaging area that moves relatively to the processing object during execution of the line processing. [2] Laser processing apparatus according to claim 1, wherein: the imaging part images the imaging area provided on a downstream side in a moving direction of the laser irradiation position with respect to the processing line during line processing. [3] Laser processing apparatus according to claim 1 or 2, wherein: the imaging part images the imaging area several times during a period of one-time execution of the line processing. [4] The laser machining apparatus according to any one of claims 1 to 3, further comprising a feed axis driver that moves the laser irradiation position in a feed direction orthogonal to the machining direction relative to the machining object by driving the support member and / or the machining head in the feed direction, wherein: among the plurality of processing lines, the processing line to be line-processed is changed by the feed axis driver, which moves the laser irradiation position with respect to the processing object, the control unit sequentially performs a first line processing of processing a first processing line from the plurality of processing lines by the line processing of moving the laser irradiation position toward a first side in the processing direction and a second line processing of processing a second processing line, different from the first processing line, from the plurality of processing lines by the line processing of moving the laser irradiation position toward a second side opposite the first side in the processing direction, the machining axis driver performs a reverse drive to bring the laser irradiation position to the second machining line by accelerating the laser irradiation position toward the second side after the laser irradiation position, which has passed through the first machining line toward the first side, is decelerated and stopped toward the first side in the machining direction, and the feed axis driver performs a continuous feed drive to move the laser irradiation position in the feed direction from a first imaginary straight line extending outside the first machining line in the machining direction along the first machining line to a second imaginary straight line extending outside the second machining line in the machining direction along the second machining line,to move continuously in a switching period from the end of the first line processing to the beginning of the second line processing, and, the control unit causes the feed axis driver to move the laser irradiation position in the feed direction during the entire time before and after the time at which movement of the laser irradiation position in the machining direction is stopped due to the reverse drive, by controlling the machining axis driver and the feed axis driver such that the feed axis driver starts the continuous feed drive before the machining axis driver stops the laser irradiation position by the reverse drive, and the feed axis driver stops the continuous feed drive after the machining axis driver stops the laser irradiation position by the reverse drive. [5] Laser processing apparatus according to one of claims 1 to 4, wherein: the mapping part maps the mapping area that includes at least the editing line while executing the line editing. [6] Laser processing apparatus according to one of claims 1 to 5, wherein: a center of the imaging area of ​​the imaging part and a focus of the laser beam to be irradiated to the laser irradiation position are arranged in the machining direction. [7] Laser processing apparatus according to claim 6, wherein: the imaging part acquires the image by full-time space imaging to cause a camera to continue exposure during an overlap period during which an unprocessed part that has not been processed by irradiating the laser beam in a target line traverses the imaging area during execution of the line processing for the one target line of the plurality of processing lines. [8] Laser processing apparatus according to claim 7, wherein: an exposure time Tc and an illuminance Tc in the full-time spatial image satisfy the following relationship for an exposure time T0 and an illuminance L0 when the camera images the object being processed stationary with respect to the camera: Lc=T0×L0 / Tc. [9] Laser processing apparatus according to claim 7 or 8, wherein: the control unit determines whether the laser irradiation position for the processing line is correct or not based on the image obtained by full-time space imaging. [10] Laser processing apparatus according to claim 9, wherein: the control unit determines whether the laser irradiation position for the processing line is correct or not based on a central part of the image excluding the two end parts in an orthogonal direction that is orthogonal to the processing direction. [11] Laser processing apparatus according to claim 9 or 10, wherein: when a positional deviation of the laser irradiation position from a target line is confirmed based on the image in an orthogonal direction orthogonal to the machining direction, the control unit determines a positional deviation amount from the one target line of the laser irradiation position in the orthogonal direction and corrects the laser irradiation position based on the positional deviation amount in the orthogonal direction when the line machining is performed according to the one target line. [12] Laser processing apparatus according to one of claims 9 to 11, wherein: when the inclination of a track of the laser irradiation position with respect to the one aiming line is confirmed based on the image, the control unit performs alignment to correct the inclination. [13] Laser processing method, comprising: Supporting a machining object having a plurality of mutually parallel machining lines by a support member so that the machining lines are parallel to a predetermined machining direction; Performing a line machining of machining the machining line by irradiating a laser beam onto a laser irradiation position by a machining head for irradiating the laser beam onto a predetermined laser irradiation position, while the laser irradiation position is moved along the machining line by a machining axis driver to relatively move the laser irradiation position in the machining direction with respect to the machining object by driving the machining head and / or the support member in the machining direction; and Obtaining an image of a part of the processing object overlapping an imaging region by an imaging part that images the imaging region that moves relatively during execution of the line processing with respect to the processing object, wherein the imaging part images a predetermined imaging region that moves relative to the processing object integrally with the laser irradiation position while the laser irradiation position moves relative to the processing object. [14] A laser processing program for causing a computer to execute the laser processing method according to claim 13. [15] A recording medium for computer-readably storing the laser processing program according to claim 14. [16] A semiconductor chip manufacturing method comprising: Processing a semiconductor substrate having a plurality of semiconductor chips defined and arrayed by processing lines by the laser processing method according to claim 13; and Separating each of the plurality of semiconductor chips by expanding a tape holding the semiconductor substrate by an adhesive force processed by the laser processing method. [17] Semiconductor chip manufactured by: Processing a semiconductor substrate having a plurality of semiconductor chips defined and arrayed by processing lines by the laser processing method according to claim 13; and Separating each of the plurality of semiconductor chips by expanding a tape holding the semiconductor substrate by an adhesive force processed by the laser processing method.

Images