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

Abstract

Imaging element 8A (first imaging element) is provided for imaging the imaging area Ri (first imaging area) located on the (+X) side (first side) in the X direction (processing direction) with respect to the laser irradiation position Lb. Imaging element 8B (second imaging element) is provided for imaging the imaging area Ri (second imaging area) located on the (-X) side (second side) in the X direction (processing direction) with respect to the laser irradiation position Lb. Imaging elements 8A and 8B image portions of the semiconductor substrate W that overlap the respective imaging areas Ri (steps S1006, S1008, and S1104). In this way, the state of the semiconductor substrate W on both sides of the laser irradiation position Lb in the X direction can be detected.

Description

TECHNICAL AREA

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

[0002] Patent literature 1 to 3 describes a laser processing technique for machining a planned division line, in which a laser beam is moved relative to a semiconductor substrate while the laser beam is directed onto the planned division line on the semiconductor substrate. As shown in patent literature 1, for example, several planned division lines are machined sequentially by moving a laser beam back and forth while the planned division line onto which the laser beam is directed is modified in forward and reverse paths in this laser processing technique.At this point, the laser beam can be precisely directed onto the planned division line by adjusting its position according to the result of an alignment process for recognizing the position of the planned division line based on an image obtained by imaging a predetermined portion of the semiconductor substrate (Patent Reference 2). As described in Patent Reference 3, the width of the planned division line can be increased by processing it with the laser beam, and the position of the unprocessed planned division line can be shifted orthogonally to a processing direction in a feed direction. To counteract such a positional shift of the planned division line, it is advantageous to image the semiconductor substrate accordingly. LIST OF REFERENCE PATENT LITERATURE Patent literature 1: Publication of Japanese patent no. 5804716 Patent Literature 2: Publication of Japanese Patent No. 5554593 Patent Literature 3: Publication of Japanese Patent No. 5037082 PRESENTATION OF THE INVENTIONAL PROBLEM

[0003] In patent literature 2, two imaging elements are arranged in the feed direction to image the workpiece (semiconductor substrate) and a processing head, respectively. However, during processing, it is necessary in some scenarios to make the workpiece's state visible in an area located in the processing direction relative to the laser irradiation position onto which the laser is directed from the processing head. More precisely, it is preferred to make the workpiece's state visible on both sides of the laser irradiation position in the processing direction.

[0004] This invention was developed in consideration of the above problem and aims to provide a technique to make detectable the state of a processing object on both sides of a laser irradiation position in a processing direction in a laser processing technique for moving the laser irradiation position relative to the laser processing object in the processing direction while a laser beam is directed from a processing head onto the laser irradiation position. SOLUTION TO THE PROBLEM

[0005] A laser processing device according to the invention comprises: a support element that supports a processing object with a plurality of parallel processing lines, such that the processing lines run parallel to a predetermined processing direction; a processing head that shines a laser beam onto 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 element and / or the processing head in the processing direction; 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 element and / or the processing head in the feed direction;a first imaging part which, in the processing direction with respect to the processing head, is located on a first side and depicts a first imaging area located on the first side of the laser irradiation position; a second imaging part which, in the processing direction with respect to the processing head, is located on a second side opposite the first side and depicts a second imaging area located on the second side of the laser irradiation position;and a control unit to process the machining line by performing line processing through the machining axis driver, which moves the laser irradiation position in the machining direction with respect to the machining object while the laser beam is directed from the machining head to the laser irradiation position, the laser irradiation position being aligned with the machining line by the feed axis driver; and the first imaging area and the second imaging area moving integrally with the laser irradiation position relative to the machining object as soon as the laser irradiation position moves, and the control unit causing the first imaging area to image a portion of the machining object that overlaps the first imaging area, and causing the second imaging area to image a portion of the machining object that overlaps the second imaging area.

[0006] A laser processing method according to the invention is a laser processing method for processing a processing line of a processing object with a plurality of processing lines parallel to each other, comprising: supporting the processing object by a support element, so that the processing lines run parallel to a predetermined processing direction;Moving a laser irradiation position in the machining direction with respect to the machining object by a machining axis driver to drive a machining head to project a laser beam onto a predetermined laser irradiation position and / or the support element in the machining direction, while the laser beam is projected from the machining head onto the laser irradiation position, wherein the laser irradiation position is brought into alignment with the machining line by a feed axis driver to drive the machining head and / or the support element in a feed direction orthogonal to the machining direction; imaging a first imaging area located on a first side of the laser irradiation position by a first imaging part arranged on the first side with respect to the machining head in the machining direction;and imaging a second imaging area located on a second side of the laser irradiation position by means of a second imaging part which, with respect to the processing head, is arranged on the second side opposite the first side in the processing direction, wherein the first imaging area and the second imaging area move integrally with the laser irradiation position relative to the processing object as the laser irradiation position moves, wherein the first imaging part images a portion of the processing object that overlaps the first imaging area, and the second imaging part images a portion of the processing object that overlaps the first imaging area.

[0007] In the invention configured as described (laser processing device and laser processing method), the first imaging element is provided for imaging the first imaging area, which is located on the first side with respect to the laser irradiation position in the processing direction, and the second imaging element is provided for imaging the second imaging area, which is located on the second side with respect to the laser irradiation position in the processing direction. The first and second imaging elements image the parts of the object being processed that overlap the first and second imaging areas. In this way, the condition of the object being processed can be detected on both sides of the laser irradiation position in the processing direction.

[0008] The laser processing device can be configured so that the control unit sequentially performs a first line processing to process a first processing line from the multitude of processing lines by moving the laser irradiation position towards the first side in the processing direction, and a second line processing to process a second processing line, different from the first processing line, from the multitude of processing lines by moving the laser irradiation position towards the second side in the processing direction.

[0009] The laser processing device can be configured such that the processing axis driver performs a first reverse drive to move the laser irradiation position to the second processing line by accelerating the laser irradiation position towards the second side after the laser irradiation position, which has traversed the first processing line towards the first side, is decelerated and stopped in the processing direction towards the first side, and the feed axis driver moves 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 outside the first processing line, to a second imaginary straight line extending in the processing direction along the second processing line to outside the second processing line.In a first switching period, from the end of the first line processing until the beginning of the second line processing, the second imaging area captures the portion of the processed object that overlaps the second imaging area during the first switching period. In such a configuration, the second imaging area can capture an image showing the state of the processed object on the second side of the laser irradiation position, effectively utilizing the first switching period to move the laser irradiation position, which has passed through the first irradiation line, towards the second processing line.

[0010] The laser processing device can be configured such that the control unit provides a first stop period during which the laser irradiation position stops in both the processing direction and the feed direction by causing the feed axis driver to stop the laser irradiation position at a time when the processing axis driver stops the laser irradiation position by means of the first reverse drive in the first switching period, and the second imaging part images the part of the processing object that overlaps the second imaging area in the first stop period.In such a configuration, an image can be captured from the second imaging part showing the state of the processing object on the second side of the laser irradiation position, effectively utilizing the first switching period of the movement of the laser irradiation position that has passed through the first processing line in the direction of the second processing line.

[0011] The laser processing device can be configured such that the control unit sequentially performs a third processing line from the plurality of processing lines by moving the laser irradiation position towards the second side in the processing direction, and a fourth processing line from the plurality of processing lines, which differs from the third processing line, by moving the laser irradiation position towards the first side in the processing direction, the processing axis driver performs a second reverse drive to move the laser irradiation position to the fourth processing line by accelerating the laser irradiation position towards the first side after the laser irradiation position,which has traversed the third processing line in the direction of the second side, was slowed down and stopped in the processing direction in the direction of the second side, and the feed axis driver moves the laser irradiation position in the feed direction in a second switching period from the end of the third line processing to the beginning of the fourth line processing, from a third imaginary straight line extending in the processing direction along the third processing line to outside the third processing line, to a fourth imaginary straight line extending in the processing direction along the fourth processing line to outside the fourth processing line, and the first image part depicts a part of the processed object that overlaps the first image area in the second switching period. In such a configuration, an image,which shows the state of the processing object on the first side of the laser irradiation position, is captured by the first imaging part, effectively utilizing the second switching period of the movement of the laser irradiation position, which has passed through the third processing line in the direction of the fourth processing line.

[0012] The laser processing device can be configured such that the control unit provides a second stop period during which the laser irradiation position stops in both the processing direction and the feed direction by causing the feed axis driver to stop the laser irradiation position at a time when the processing axis driver stops the laser irradiation position through the second reverse drive in the second switching period, and the first imaging part maps the part of the processing object that overlaps the first imaging area in the second stop period.In such a configuration, an image showing the state of the processing object on the first side of the laser irradiation position can be captured by the first imaging part, effectively utilizing the second switching period of moving the laser irradiation position, which has passed through the third processing line in the direction of the fourth processing line.

[0013] The laser processing device can be configured such that the first imaging element captures the portion of the object being processed that overlaps the first imaging area during the execution of the first line processing, and the second imaging element captures the portion of the object being processed that overlaps the second imaging area during the execution of the second line processing. In such a configuration, an image showing the state of the object being processed on the first side of the laser irradiation position can be captured by the first imaging element, effectively utilizing one execution period of the first line processing, and an image showing the state of the object being processed on the second side of the laser irradiation position can be captured by the second imaging element, effectively utilizing one execution period of the second line processing.

[0014] A laser processing program according to the invention causes a computer to execute the laser processing method described above.

[0015] A recording medium according to the invention stores the laser processing program described above in a computer-readable format.

[0016] A semiconductor chip manufacturing method according to the invention comprises: processing a semiconductor substrate having a plurality of semiconductor chips which are delimited and arranged by processing lines, by the laser processing method described above; and separating each of the plurality of semiconductor chips by stretching a band which holds the semiconductor substrate by an adhesive force, processed by the laser processing method.

[0017] A semiconductor chip according to the invention is produced by: processing a semiconductor substrate comprising a plurality of semiconductor chips, which are delimited and arranged by processing lines, by the laser processing method described above; and separating each of the plurality of semiconductor chips by stretching a band which holds the semiconductor substrate by an adhesive force, processed by the laser processing method. IMPACT OF THE INVENTION

[0018] According to the invention, it is possible to make the state of a processing object on both sides of a laser irradiation position in a processing direction detectable in a laser processing method in which the laser irradiation position is moved relative to the processing object in the processing direction, while a laser beam is emitted from a processing head onto the laser irradiation position. BRIEF DESCRIPTION OF THE DRAWINGS [Fig. 1] Front view, which schematically shows an example of a laser processing device according to the invention. [ Fig. 2] Top view, schematically showing the laser processing device of the Fig. 1 shows. [ Fig. 3] Block diagram showing the electrical configuration of the laser processing device Fig. 1 shows. [ Fig. 4] Flowchart showing an example of a process for producing a laser-processed substrate where the laser processing has already been carried out. [ Fig. 5] Flowchart showing an example of removing the ring frame. [ Fig. 6] Flowchart showing an example of the transfer of the ring frame. [ Fig. 7A] Top view, schematically showing an example of a process as described in the flowcharts of the 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 the 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 the 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 the 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 the Fig. 5 and Fig. 6 is carried out. [ Fig. 8] Flowchart showing an example of how to store the ring frame. [ Fig. 9] Flowchart showing an example of ring frame alignment. [ Fig. 10] Top view, which schematically shows an example of a process carried out during ring frame alignment. [ Fig. 11] Flowchart showing an example of substrate processing. [ Fig. 12] Top view, schematically showing an example of a process as described in the flowchart of Fig. 11 will be 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 processing for each planned division line. [ Fig. 15A] Diagram schematically showing a first example of a process that follows the flowchart of Fig. 14 will be carried out. [ Fig. [15B] Diagram, which schematically shows a second example of the flowchart of Fig. The 14th completed process shows. [ Fig. [15C] Diagram, which schematically shows a third example of the flowchart of Fig. The 14th completed process shows. [ Fig. [15D] Diagram, which schematically shows a fourth example of the flowchart of Fig. The 14th completed process shows [ Fig. [15E] Diagram, which schematically shows a fifth example of the flowchart of Fig. The 14th completed process shows [ Fig. [15F] Diagram, which schematically shows a sixth example of the flowchart of Fig. The 14th completed process shows. [ Fig. [15G] Diagram, which schematically shows a seventh example of the flowchart of Fig. The 14th completed process shows. [ Fig. 16] Flowchart showing a first application example of line processing for each planned division line. [ Fig. 17] Diagram schematically showing an example of a process that follows the flowchart of Fig. 16 will be carried out. [ Fig. 18] Flowchart showing a second application example of line processing for each planned division line. [ Fig. 19A] Diagram schematically showing a first example of a process that follows the flowchart of Fig. 18 will be carried out. [ Fig. [19B] Diagram, which schematically shows a second example of the flowchart of Fig. The 18th completed process is shown. [ Fig. 20] Diagram schematically showing an example of an image of the semiconductor substrate produced in step S1008 of Fig. 16 or step S1104 of Fig. 18 was achieved. [ Fig. 21] Flowchart showing an example of a procedure for determining laser processing conditions during line processing. [ Fig. 22A] Diagram with parameters relating 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 laser processing conditions Fig. 21 must be referenced. DESCRIPTION OF THE EXECUTION FORMS

[0019] Fig. 1 is a front view, which schematically shows an example of a laser processing device according to the invention, and Fig. 2 is a top view that schematically shows the laser processing device. Fig. Figure 1 shows. In both figures and the following figures, an X-direction, which is a horizontal direction, a Y-direction, which is a horizontal direction orthogonal to the X-direction, and a Z-direction, which is a vertical direction, are shown accordingly. Furthermore, a (+X) side in the X-direction (right side in Fig. 2) and an (-X)-side (left side in Fig. 2), which is opposite the (+X) side in the X direction, as shown, and a (+Y) side in the Y direction (top side in Fig. 2) and a (-Y)-side (bottom side in Fig. 2), which is opposite the (+Y) side in the Y direction, is appropriately represented.

[0020] The laser processing device 1 processes a semiconductor substrate W by shining a laser beam onto the semiconductor substrate W (processing object). This semiconductor substrate W is held by a ring frame Fr over a tape E. The tape E is a saw-cut foil or bonding tape, and the front (top) surface of the tape E is adhesive. The ring frame Fr has an outer shape obtained by cutting portions of a regular octagon to provide slots Fs, and a circular opening Fo is provided in the 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 circumferential edge of the front surface of the tape E is bonded to the bottom surface of the ring frame Fr by an adhesive force. Furthermore, 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 device 1 while being held by the ring frame Fr over the belt E. It is noted that the semiconductor substrate W has a front and a back opposite the front, and that an electronic circuit is formed on the front of the semiconductor substrate W, while the back of the semiconductor substrate W is flat. The downward-facing front of the semiconductor substrate W is bonded to the front of the belt E, i.e., the semiconductor substrate W is held by its upward-facing back.

[0021] The laser processing device 1 is provided with a substrate storage part 2 for storing the semiconductor substrate W and a clamping platform 3 (support element) for holding the semiconductor substrate W removed from the substrate storage part 2. The laser processing device 1 is provided with a base plate 11 in the form of a flat plate, and the substrate storage part 2 and the clamping platform 3 are supported by the base plate 11. The clamping platform 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 clamping platform 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.

[0022] The substrate storage part 2 comprises a substrate storage cassette 21. The substrate storage cassette 21 includes a pair of side walls 22, which are provided on both sides in the X-direction, and an opening 23, which is provided between the side walls 22, and the opening 23 is directed towards the (-Y) side (i.e., towards the substrate transfer area Aw). The pair of side walls 22 are flat plates that are perpendicular to the X-direction and are opposite each other in the X-direction. Furthermore, support projections 24 are provided within each of the pair of side walls 22. A pair of support projections 24, which face each other in the X-direction, are located at the same height. The ring frame Fr, which holds the semiconductor substrate W, can be inserted from the (-Y) side through the opening 23 into a position above the pair of support projections 24.Both ends in the X-direction of the ring frame Fr inserted in this manner are supported from below by the pair of support projections 24. This means that one side above the pair of support projections 24 acts as a slot 25 for receiving the ring frame Fr, and the ring frame Fr, which is 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, which is 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.

[0023] 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 comprises a Z-axis drive transmitter 271 for supporting the Z-axis slider 26 in the Z-direction and a Z-axis cassette motor 272 for driving the Z-axis slider 26, which is supported on the Z-axis drive transmitter 271, in the Z-direction. The Z-axis drive unit 271 has a ball screw driven by the Z-axis cassette motor 272, and the Z-axis slider 26 is attached to a nut on the ball screw. However, a specific configuration of the Z-axis drive mechanism 27 is not limited to this example and can be a linear motor.Such a Z-axis drive mechanism 27 moves the substrate storage cassette 21 mounted on the Z-axis slide 26 in the Z direction by driving the Z-axis slide 26 mounted on the Z-axis drive transmitter 271 by means of the Z-axis cassette motor 272.

[0024] A substrate insertion height 211 is defined 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 from which it is removed can be changed by moving the substrate storage cassette 21 in the Z-direction by the Z-axis drive mechanism 27, thus changing the slot 25 located at the substrate insertion height 211 from a variety of slots 25.

[0025] In contrast, the laser processing device 1 is provided with a Y-axis conveying mechanism 4 for transporting the ring frame Fr in the Y direction between the slot 25 on the substrate insertion height 211 and the substrate transfer area Aw. The Y-axis conveying mechanism 4 has a lifting hand 41, a Y-axis slider 43 for carrying the lifting hand 41, and a Y-axis drive mechanism 45 for driving the Y-axis slider 43 in the Y direction. The Y-axis drive mechanism 45 is a single-axis robot that is mounted on the base plate 11 by a frame (not shown) and includes a Y-axis drive transmitter 451 for the Y-axis slider 43 being movable in the Y direction and a Y-axis lifting hand motor 452 for driving the Y-axis slider 43, which is mounted on the Y-axis drive transmitter 451, in the Y direction.The Y-axis drive unit 451 has a ball screw driven by the Y-axis lift hand motor 452, and the Y-axis slider 43 is attached to a nut on the ball screw. However, a specific configuration of the Y-axis drive mechanism 45 is not limited to this example and can be a linear motor. Such a Y-axis drive mechanism 45 moves the lift 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 unit 451, via the Y-axis lift hand motor 452.

[0026] The lifting hand 41 has a base part 411, which rests on the Y-axis slider 43, and a fork 412 that projects from the base part 411 towards 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 via the Y-axis drive mechanism 45, as described later.

[0027] Furthermore, the laser processing device 1 is equipped with an XZ-axis conveying mechanism 5 for transporting the ring frame Fr in the X-direction between the lifting hand 41, which is located in the substrate transfer area Aw, and the clamping stage 3. The XZ-axis conveying mechanism 5 has a suction hand 51, an X-axis slider 53 to support the suction hand 51, and an X-axis driver 55 to drive the X-axis slider 53 in the X-direction. The X-axis driver 55 is a single-axis robot that is mounted on the base plate 11 by a frame (not shown) and has an X-axis drive transmitter 551 for the X-axis slider 53 being 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 transmitter 551 in the X-direction.The X-axis drive unit 551 has a ball screw driven by the X-axis suction hand motor 552, and the X-axis slide 53 is attached to a nut on the ball screw. However, a specific configuration of the X-axis driver 55 is not limited to this example and can be a linear motor. Such an X-axis driver 55 moves the suction hand 51, mounted on the X-axis slide 53, in the X-direction by driving the X-axis slide 53, mounted on the X-axis drive unit 551, through the X-axis suction hand motor 552.

[0028] The XZ-axis conveying mechanism 5 further comprises a Z-axis slider 56, which is attached to the suction hand 51, and a Z-axis driver 58 for driving the Z-axis slider 56 in the Z direction with respect to the X-axis slider 53. This means that the suction hand 51 is supported via 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 slide 53 and includes a Z-axis drive unit 581 for the Z-direction movable bearing of the Z-axis slide 56 and a Z-axis suction hand motor 582 for driving the Z-axis slide 56, which is mounted on the Z-axis drive unit 581, in the Z-direction. The Z-axis drive unit 581 has a ball screw driven by the Z-axis suction motor 582, and the Z-axis slide 56 is attached to a nut on the ball screw.However, a specific configuration of the Z-axis driver 58 is not limited to this example and can be a linear motor. The Z-axis slider 56 extends from the Z-axis driver 58 to one side below the X-axis drive unit 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, which is mounted on the Z-axis slider 56, in the Z-direction by driving the Z-axis slider 56, which is mounted on the Z-axis drive unit 581, via the Z-axis suction hand motor 582.

[0029] The suction hand 51 has a base part 511, which is mounted on the Z-axis slide 56, and an annular suction element 512, which projects from the base part 511 in the direction of the (+Y) side. The annular suction element 512 has a circular ring shape, and a plurality of suction holes open into a base surface 513 of the annular suction element 512. The ring frame Fr can be held from above by the suction hand 51 by drawing the ring frame Fr towards it through a vacuum created in each suction hole of the base surface 513, while the base surface 513 of this annular suction element 512 is brought into contact with the ring frame Fr from above.The XZ-axis conveying mechanism 5 moves the ring frame Fr, which is held by the annular suction element 512 of the suction hand 51, between the substrate transfer area Aw and the clamping 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.

[0030] The clamping platform 3 has a suction plate 31 on which the ring frame Fr, which carries the semiconductor substrate W over the tape 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 tape E can be attached to the suction plate 31 by drawing the tape E into contact with the upper surface 311 by a vacuum created in each suction hole of the upper surface 311 of the suction plate 31. Furthermore, the clamping platform 3 has a plurality of clamps 32 provided at the circumferential edge of the suction plate 31. This clamping platform 3 fixes the ring frame Fr to the suction plate 31 by causing the clamps 32 to face the ring frame Fr, which is placed on top of the suction plate 31, 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 retracting the clamps 32 laterally away from the ring frame Fr.

[0031] As just described, the clamping platform 3 holds the semiconductor substrate W over the tape E on the ring frame Fr by drawing the tape E against the suction plate 31 and fixing the ring frame Fr by the clamps 32. By using the clamps 32 in this combination, the tape E can be drawn against the suction plate 31 with a weak suction force, and the influence of the suction force of the tape E on the semiconductor substrate W can be reduced compared to the case in which the semiconductor substrate W is held only by the suction of the tape E against the suction plate 31.

[0032] Furthermore, the laser processing device 1 is equipped with an X-axis drive table 6 for receiving the clamping platform 3. The X-axis drive table 6 is arranged on the base plate 11 and drives the clamping platform 3 in the X direction, the Y direction, and a θ direction with respect to the base plate 11. The θ direction is a direction of rotation about an axis of rotation parallel to the Z direction. This means that the X-axis drive table 6 has a Y-axis guide 61, which is mounted parallel to the Y direction on the base plate 11, a Y-axis slider 62, which is movably mounted 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 the Y-direction movable bearing of the Y-axis slide 62 and a Y-axis table motor 632 for driving the Y-axis slide 62, which is mounted on the Y-axis drive unit 631, in the Y-direction. The Y-axis drive unit 631 has a ball screw driven by the Y-axis table motor 632, and the Y-axis slide 62 is attached to a nut on the ball screw. However, the specific configuration of the Y-axis driver 63 is not limited to this example and can also be a linear motor.

[0033] The XYθ drive table 6 further comprises 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 transmitter 651 for the X-direction movable bearing of the X-axis slider 64 and an X-axis table motor 652 for driving the X-axis slider 64, which is mounted on the X-axis drive transmitter 651, in the X-direction. The X-axis drive unit 651 has a ball screw driven by the X-axis table motor 652, and the X-axis slider 64 is attached to a nut on the ball screw. However, the specific configuration of the X-axis driver 65 is not limited to this example and can also be a linear motor.

[0034] The XYθ drive table 6 further comprises a θ-axis table motor 66, which is mounted on the X-axis slide 64. This θ-axis table motor 66 drives the clamping stage 3 in the θ direction with respect to the X-axis slide 64.

[0035] 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.

[0036] The laser processing device 1 is further equipped with a laser processing unit 7 for performing laser processing on the semiconductor substrate W held on the clamping platform 3. The laser processing unit 7 has a processing head 71, which faces the semiconductor substrate W held on the clamping platform 3 from above. The processing head 71 has a laser light source 72 for generating a laser beam B with a predetermined frequency and an optical system 73 (a lens, an aperture, and the like) for directing the laser beam B emitted by 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 focuses 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 that overlaps the laser irradiation position Lb.

[0037] The laser processing part 7 further comprises a Z-axis slide 78 for carrying the processing head 71 and a Z-axis drive 79 for driving the Z-axis slide 78 in the Z direction. The Z-axis drive 79 is a single-axis robot mounted on the base plate and comprises a Z-axis drive transmitter 791 for the Z-direction movable bearing of the Z-axis slide 78 and a Z-axis head motor 792 for driving the Z-axis slide 78, which is mounted on the Z-axis drive transmitter 791, in the Z direction. The Z-axis drive unit 791 has a ball screw driven by the Z-axis head motor 792, and the Z-axis slider 78 is attached to a nut on the ball screw. However, a specific configuration of the Z-axis driver 79 is not limited to this example and can 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 slide 78, which is mounted on the Z-axis drive transmitter 791, through the Z-axis head motor 792 to move the machining head 71 mounted on the Z-axis slide 78 in the Z direction.

[0038] The laser processing device 1 is further equipped with imaging elements 8 for imaging the semiconductor substrate W, which is held on the clamping platform 3. More precisely, two imaging elements 8 are arranged transversely to the laser processing element 7 in the X-direction. To distinguish these two imaging elements 8, the imaging element 8 on the (+X) side of the laser processing element 7 is designated as imaging element 8A, and the imaging element 8 on the (-X) side of the laser processing element 7 is designated as imaging element 8B. In this way, imaging element 8A, the laser processing element 7, and imaging element 8B are arranged in a row in the X-direction. It should be noted that each of the imaging elements 8A and 8B has a common basic configuration. Therefore, the components common to imaging elements 8A and 8B are described without distinction.

[0039] Imaging section 8 includes the infrared camera 81, which is directed downwards towards the semiconductor substrate W held on the clamping platform 3. This infrared camera 81 has a predefined imaging area Ri (in other words, a field of view) and is directed downwards towards this imaging area Ri 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.

[0040] Figure 8 further shows a Z-axis slider 88 for carrying 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 transmitter 891 for mounting the Z-axis driver 88 so that it can be moved in the Z direction, and a Z-axis camera motor 892 for driving the Z-axis slider 88, which is mounted on the Z-axis drive transmitter 891, in the Z direction. The Z-axis drive unit 891 has a ball screw driven by the Z-axis camera motor 892, and the Z-axis slider 88 is attached to a nut on the ball screw. However, a specific configuration of the Z-axis driver 89 is not limited to this example and could 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, which is mounted on the Z-axis drive transmitter 891 by the Z-axis camera motor 892, to move the infrared camera 81 mounted on the Z-axis slider 88 in the Z direction.

[0041] It is noted that the infrared camera 81 of imaging part 8A and the infrared camera 81 of imaging part 8B have different resolutions. In particular, the infrared camera 81 of imaging part 8A has a higher resolution, i.e., a narrower field of view, than the infrared camera 81 of imaging part 8B. However, the resolutions of the infrared cameras 81 need not differ between imaging parts 8A and 8B, and these infrared cameras 81 can have the same resolution. Furthermore, in this example, the centers of the imaging area Ri of imaging part 8A, the laser irradiation position Lb of the processing head 71, and the imaging area Ri of 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.

[0042] Fig. Figure 3 is a block diagram showing the electrical configuration of the laser processing device. Fig. 1 shows. As in Fig. Figure 3 shows the laser processing device 1 with a control unit 100 for controlling the Fig. 1 and Fig. The control unit 100 comprises a handling control computer 110, which is responsible for controlling a substrate transport system (substrate storage part 2, Y-axis conveying mechanism 4 and XZ-axis conveying mechanism 5) with respect to the transport of the semiconductor substrate W in the laser processing device 1, and a laser processing control computer 120, which is responsible for controlling a laser processing system (clamping stage 3, XYθ drive table 6, laser processing part 7 and imaging parts 8) with respect to the laser processing of the semiconductor substrate W.

[0043] The control unit 100 further comprises a cassette controller 111 to control 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 sets the position in the Z-direction of the substrate storage cassette 21 by controlling the Z-axis cassette motor 272 and sets the position in the Y-direction of the lifting hand 41 by controlling the Y-axis lifting hand motor 452.

[0044] The control unit 100 also includes a hand controller 112 to control the conveying 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 sets the position in the X-direction of the suction hand 51 by controlling the X-axis suction hand motor 552 and sets 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 to draw in the suction holes in the base surface 513 of the annular suction element 512 of the suction hand 51. This means that the hand controller 112 draws the ring frame Fr through the suction hand 51 by supplying a vacuum to the suction holes via the suction pump 591, and separates the ring frame Fr from the suction hand 51 by stopping the supply of the vacuum to the suction holes via the suction pump 591.

[0045] The control unit 100 also includes a stage controller 121 to control a substrate clamping process by the clamping stage 3 and the clamping stage 3 drive in response to a command from the laser processing control computer 120. The stage controller 121 sets the positions in the X, Y, and θ directions of the clamping stage 3 by controlling the X-axis table motor 652, the Y-axis table motor 632, and the θ-axis table motor 66. Furthermore, the stage controller 121 controls the clamping of the ring frame Fr to the suction plate 31 and the release of the clamping 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 drawing in the suction holes in the top 311 of the suction plate 31.This means that the stage controller 121 draws the tape E through the suction plate 31 by supplying a vacuum to the suction holes via the suction pump 692, and releases the suction of the tape E through the suction plate 31 by stopping the supply of the vacuum to the suction holes via the suction pump 692.

[0046] The control unit 100 further comprises a camera controller 122A for controlling the imaging section 8A and a camera controller 122B for controlling the imaging section 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 sections 8A, 8B, respectively. This means that each of the camera controllers 122A, 122B causes the infrared camera 81 to image the semiconductor substrate W in order to obtain an image of the semiconductor substrate W, and drives the infrared camera 81 in the Z direction by the Z-axis camera motor 892 to set a distance in the Z direction between the infrared camera 81 and the semiconductor substrate W.

[0047] The control unit 100 further comprises a processing head controller 123 for controlling the laser processing part 7. The processing head controller 123 drives the laser light source 72 to emit a laser beam B from the laser light source 72 and drives the processing head 71 in the Z-direction via the Z-axis head motor 792 to establish a distance in the Z-direction between the processing head 71 and the semiconductor substrate W. The processing head 71 further comprises 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 processing head 71 further comprises a focusing mechanism 75. The focusing mechanism 75 sets a position onto which the laser beam B is focused by shifting a focus of the optical system 73 in the Z direction.In particular, the processing 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 processing head 71 from the semiconductor substrate W, which is detected by the height detector 74.

[0048] It is noted that each function of the control unit 100 described above can be implemented by a processor such as a CPU (Central Processing Unit), an FPGA (Field Programmable Gate Array), etc.

[0049] The control unit 100 also includes a memory 190, which is a storage device such as an HDD (Hard Disk Drive) or an SSD (Solid State Drive). This memory 190 stores a laser processing program 191 for specifying operations described later, which are performed in the laser processing device 1 for laser processing of the semiconductor substrate W. This means that the control unit 100 executes any control that will later be performed based on the Fig. As described in sections 4 to 22C, the laser processing program 191 is implemented. It is noted that the laser processing program 191 is provided by a recording medium 192 outside the laser processing device 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 are a USB (Universal Serial Bus) storage device, a storage device of an external computer, and the like.

[0050] Fig. Figure 4 is a flowchart showing an example of a process for manufacturing a laser-processed substrate for which the laser processing has already been performed. The flowchart of Fig. Step 4 is executed according to a 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 transfers the ring frame Fr from the lifting hand 41 to the clamping platform 3 in the substrate transfer area Aw. 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 platform 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.

[0051] Fig. Figure 5 is a flowchart showing an example of removing the ring frame. Fig. Figure 6 is a flowchart showing an example of the ring frame transfer, and Fig. Figures 7A to 7E are top views that schematically show an example of a process, which, according to the flowcharts of the Fig. 5 and Fig. 6 is carried out.

[0052] In step S201 of the Fig. 5 confirms the control unit 100 whether the lifting hand 41 is empty or not, i.e., whether the ring frame Fr is not placed on the lifting hand 41 or not. Whether the lifting hand 41 is empty or not can be confirmed based on a history or similar of operations performed by the lifting hand 41. The flowchart from Fig. Step 5 is terminated if the lifting handle 41 is not empty (“NO” in step S201), whereas the process continues to step S201 if the lifting handle 41 is empty (“YES” in step S201).

[0053] In step S202, the control unit 100 confirms whether at least part of the lifting hand 41 is located in the substrate storage cassette 21, i.e., whether it is on the inside (i.e., the (+Y) side) of the substrate storage cassette 21, as indicated by the opening 23 of the substrate storage cassette 21. Whether at least part of the lifting hand 41 is located in the substrate storage cassette 21 can be confirmed, for example, by the position of the lifting hand 41, which is indicated by an output from an encoder of the Y-axis lifting hand motor 452 for the drive of the lifting hand 41 in the Y direction. The process proceeds to S204 without performing step S203 if the lifting handle 41 is withdrawn to the (-Y) side from the substrate storage cassette 21 (“NO” in step S202), while it proceeds to step S203 if part of the lifting handle 41 is inside the substrate storage cassette 21 (“YES” in step S202).In step S203, the control unit 100 pulls the lifting hand 41 out of the substrate storage cassette 21 in the direction of the (-Y) side and pulls the lifting hand 41 back in the direction of the (-Y) side of the substrate storage cassette 21 by driving the lifting hand 41 in the direction of the (-Y) side by the Y-axis lifting hand motor 452.

[0054] In step S204, the control unit 100 positions slot 25, in which the ring frame Fr is stored, at a position that is a predetermined height higher than the substrate insertion height 211 by driving the substrate storage cassette 21 in the Z-direction by the Z-axis cassette motor 272. This predetermined height is shorter than the distance between the slots 25 adjacent in the Z-direction. In this way, the base of the ring frame Fr to be removed is set to a position that is a predetermined height higher than the lifting handle 41.

[0055] In step S205, the control unit 100 sets the following as in Fig. As shown in Figure 7A, the lifting hand 41 is inserted into the substrate storage cassette 21 by the Y-axis lifting hand motor 452 driving the lifting hand 41 towards the (+Y) side. In this way, the lifting hand 41 faces the ring frame Fr and can be removed from below through a gap.

[0056] In step S206, the control unit 100 lowers the substrate storage cassette 21 in the Z direction using the Z-axis cassette motor 272. Therefore, the ring frame Fr to be removed is placed on the lifting hand 41 and moved upwards with respect to the slot 25 (i.e., the pair of support projections 24 that define the slot 25).

[0057] 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 towards the (-Y) side via the Y-axis lifting hand motor 452. In this way, as in Fig. 7B shows the ring frame Fr, which is placed on the lifting handle 41, in the substrate transfer area Aw.

[0058] In step S301 of the Fig. 6 causes the control unit 100 to face the suction hand 51 towards the ring frame Fr, which is supported from above on the lifting hand 41 in the substrate transfer area Aw, as shown in Fig. Figure 7C shows the position of the suction hand 51 in the X-direction being set by the X-axis suction hand motor 552. At this point, the control unit 100 sets the suction hand 51 to a position higher than the ring frame Fr by adjusting the height of the suction hand 51 using the Z-axis suction hand motor 582. Therefore, the suction hand 51 is facing the ring frame Fr across a gap.

[0059] In step S302, the control unit 100 brings the base surface 513 of the suction hand 51 into contact with the upper surface of the ring frame Fr by lowering the suction hand 51 relative to the ring frame Fr via the Z-axis drive transmission 581. In step S303, the control unit 100 causes the suction pump 591 to create a vacuum in the suction holes provided in the base surface 513 of the suction hand 51, and the suction hand 51 draws the ring frame Fr towards it by this vacuum. In this way, the ring frame Fr is held by the suction hand 51. In step S304, the control unit 100 raises the suction hand 51 via the Z-axis suction hand motor 582. In this way, the suction hand 51 lifts the ring frame Fr from the lifting hand 41.

[0060] In step S305, the control unit 100 causes the suction hand 51 to point from above the clamping stage 3 as the transfer target of the ring frame Fr by driving the suction hand 51 towards the (+X) side by the X-axis suction hand motor 552, as shown in Fig. Figure 7D shows that at this point, the control unit 100 positions the ring frame Fr, which is held by the suction hand 51, in a position higher than the clamping stage 3 by adjusting the height of the suction hand 51 via the Z-axis suction hand motor 582. Therefore, the ring frame Fr, held by the suction hand 51, faces the clamping stage 3 across a gap.

[0061] 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 via 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.

[0062] In step S308, the control unit 100 confirms whether the transfer target of the ring frame Fr is the clamping platform 3 or not. If the transfer target of the ring frame Fr is, for example, the lifting hand 41, as in step S104, which is described later, "NO" is determined in step S308 and the flowchart of Fig. Step 6 is complete. Since the transfer target of the ring frame Fr is the clamping stage 3, "YES" is determined in step S308, and the process proceeds to S309.

[0063] In step S309, the control unit 100 clamps the ring frame Fr, which is placed on the suction plate 31 of the clamping platform 3, between the clamps 32 and the suction plate 31 to clamp the ring frame Fr by driving the clamp drive 691. Furthermore, in step S310, the control unit 100 causes the suction pump 591 to create a vacuum in the suction holes provided in the upper surface 311 of the suction plate 31, and the suction plate 31 draws in the band E connected to the ring frame Fr by this vacuum. In this way, the ring frame Fr is held by the clamping platform 3. In step S311, the control unit 100 raises the suction hand 51 by means of 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 shows the transfer of the ring frame Fr from the substrate storage cassette 21 to the clamping stage 3 completed (steps S101, S102 of Fig. 4).

[0064] In step S103 of the Fig. 4. Substrate preparation is performed to process the semiconductor substrate W, which is held on the clamping stage 3, using the laser beam B, and the laser beam B is directed onto the multitude of planned division lines provided on the semiconductor substrate W. This substrate preparation will be described in detail later.

[0065] Once substrate processing is complete, steps S104 and S105 are performed. In step S104, the suction hand 51 transfers the ring frame Fr from the clamping platform 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, which is 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 clamping platform 3 to the substrate transfer area Aw. In particular, 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 corresponding to the one in Fig. The process shown in sections 7A to 7E, which is the opposite of the one shown, will be carried out. Fig. Figure 8 is a flowchart showing an example of how to store the ring frame.

[0066] Since the process performed in step S104 was Fig. 6 the process performed in step S102 of Fig. Since step 6 is similar, the description focuses on the differences from the process described above, and the description of common process parts is omitted where applicable. In step S301 of Fig. Step 6 causes the control unit 100 to face the suction hand 51 from above towards the ring frame Fr, which is placed on the clamping platform 3, by adjusting the position of the suction hand 51 in the X-direction using the X-axis suction hand motor 552. The control unit 100 then lowers the suction hand 51 onto the ring frame Fr (step S302) and causes the suction hand 51 to draw suction onto the ring frame Fr (step S303). The control unit 100 then raises the suction hand 51 (step S304). In this way, the suction hand 51 lifts the ring frame Fr from the clamping platform 3.

[0067] In step S305, the control unit 100 drives the suction hand 51 towards the (-X) side using the X-axis suction hand motor 552. At this point, the lifting hand 41 is in the substrate transfer area Aw in a waiting position. Thus, the suction hand 51 points from above the lifting hand 41 into the substrate transfer area Aw as the transfer target for the ring frame Fr. The control unit 100 then places the ring frame Fr, held by the suction hand 51, onto the lifting hand 41 by lowering the suction hand 51 using the Z-axis suction hand motor 582 (step S306). The control unit 100 then 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 target of the ring frame Fr is the clamping stage 3 or not.Since the transfer target of the ring frame Fr is not the clamping platform 3, but the lifting hand 41, “NO” is determined in step S308, and the flow diagram of . Fig. 6 is finished.

[0068] In step S401 of Fig. Step 8 confirms whether the ring frame Fr has been placed on the lifting hand 41 or not. The placement of the ring frame Fr on the lifting hand 41 can be confirmed, for example, based on a sequence of operations performed by the suction hand 51 to place 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 at least part of the lifting hand 41 is located in the substrate storage cassette 21 or not (step S402), as described in step S202 above. The process proceeds to step S404 without performing step S403 if the lifting hand 41 is withdrawn to the (-Y) side from the substrate storage cassette 21 (“NO” in step S402), while it proceeds to step S403 if part of the lifting hand 41 is inside the substrate storage cassette 21 (“YES” in step S402).In step S403, the control unit 100 retracts the lifting hand 41 towards the (-Y) side of the substrate storage cassette 21 and retracts the lifting hand 41 towards the (-Y) side from the substrate storage cassette 21 by driving the lifting hand 41 towards the (-Y) side through the Y-axis lifting hand motor 452.

[0069] In step S404, the control unit 100 positions the slot 25 (in other words, the pair of support projections 24 that define slot 25), in which the ring frame Fr is to be stored, in a position that is a predetermined height lower than the substrate insertion height 211 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 that is a predetermined height lower than the base of the ring frame Fr, which is supported by the lifting handle 41.

[0070] In step S405, the control unit 100 inserts the lifting hand 41 into the substrate storage cassette 21 by moving the lifting hand 41 towards the (+Y) side via the Y-axis lifting hand motor 452. In this way, the pair of support projections 24, which define the slot 25 for storage, are positioned from below, across a gap and supported on the lifting hand, facing the ring frame Fr.

[0071] In step S406, the control unit 100 lifts the substrate storage cassette 21 in the Z-direction by means of the Z-axis cassette motor 272. In this way, the ring frame Fr is positioned on the pair of support projections 24, which define the storage slot 25, and lifted relative to the lifting hand 41. In step S407, the control unit 100 retracts the lifting hand 41 to the outside of the substrate storage cassette 21 by driving the lifting hand 41 towards the (-Y) side by means of the Y-axis lifting hand motor 452.

[0072] It is noted that when removing or storing the ring frame Fr from or into the substrate storage cassette 21, a ring frame alignment Fr with respect to the lifting handle 41 can be carried out. Fig. 9 is a flowchart showing an example of ring frame alignment, and Fig. Figure 10 shows top views that schematically illustrate an example of a process performed during ring frame alignment. It is noted that the flowchart in Fig. 9 is carried out by a control of the control unit 100.

[0073] In Fig. Figure 10 shows elements (alignment projections 413 and the like) below the suction hand 51, extending through the suction hand 51. This means that the lifting hand 41 in this example has a plurality of alignment projections 413 that extend upwards from the base part 41. The plurality of these alignment projections 413 corresponds to the plurality of slots Fs of the ring frame Fr. The ring frame alignment is carried out with the aid of the alignment projections 413 and the slots Fs.

[0074] In this ring frame alignment, the ring frame Fr is suctioned onto the lifting hand 41 by the suction hand 51 (step S501). Then, the suction hand 51, which holds the ring frame Fr, is lifted to separate the ring frame Fr upwards from the lifting hand 41 (step S502). At this point, the separation height of the ring frame Fr from the lifting hand 41 is set such that the ring frame Fr is located in the Z-direction at a height between the lower and upper ends of the alignment projections 413.

[0075] In step S503, an XYθ floating mechanism 561, which is integrated into the Z-axis slider 56, is activated. This XYθ floating mechanism 561 selectively assumes a floating state for the floating support of the suction hand 51 and a locked state for the fixed support of the suction hand 51. Floating support means that the suction hand 51 is supported in a state in which it can move in the X, Y, and θ directions relative to the XYθ floating mechanism 561, while fixed support means that the suction hand 51 is supported in a state in which it is fixed to the XYθ floating mechanism 561. When the XYθ floating mechanism 561 is switched on in step S503, the XYθ floating mechanism 561 supports the suction hand 51 in a floating position 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.

[0076] In step S504, the lifting hand 41 moves in the Y direction, and the alignment projections 413 of the lifting hand 41 are brought into contact with the circumferential edge of the ring frame Fr, which is held by the suction hand 51. At this point, the suction hand 51 moves relative to the XYθ floating mechanism 561, so that the alignment projections 413 follow the circumferential edge of the ring frame Fr. As a result, as shown in the field of step S504, Fig. 10 shows the respective alignment projections 413 of the lifting hand 41 being engaged with the respective slots Fs of the ring frame Fr and the ring frame Fr being positioned in relation to the lifting hand 41.

[0077] In step S505, the XYθ floating mechanism 561 is locked. This securely holds the suction hand 51 in place. In step S506, the suction of the ring frame Fr by the suction hand 51 is released, and the ring frame Fr is placed onto the lifting hand 41. In step S507, the XYθ floating mechanism 561 is disengaged, and the suction hand 51 is supported by the Z-axis slider 56 while attached to it. This allows the ring frame Fr to be positioned relative to the lifting hand 41 (ring frame alignment).

[0078] Next, the substrate preparation will be described in detail. Fig. 11 is a flowchart showing an example of substrate processing, and Fig. Figure 12 shows top views that schematically illustrate an example of a process, which, according to the flowchart of the Fig. 11 is carried out. The flowchart of the Fig. 11 is carried out by a control of the control unit 100.

[0079] 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. 13B is a flowchart showing an example of the stage level specification used in the calibration of Fig. 13A is carried out, and Fig. 13C is a flowchart showing an example of the substrate level specification used in the calibration of Fig. 13A is carried out. It is noted that during the calibration of Fig. 13A, the suction plate 31 or the semiconductor substrate W is imaged as required. This description assumes that the imaging is performed by imaging section 8B. However, the following procedure can be performed similarly even if the imaging is performed by imaging section 8A.

[0080] In step S701 of the calibration of Fig. 13A will be the stage level specification ( Fig. 13B). As in Fig. As shown in Figure 13B, during the stage level specification, a count value I for distinguishing a plurality of (three) mapping 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 mapping point Ps(I) is, for example, a marking with a predefined pattern.

[0081] In step S803, the control unit 100 ensures that the imaging point Ps(I) of the infrared camera 81 is facing from below by adjusting the position of the clamping stage 3 using the XYθ drive table 6. In this way, the imaging point Ps(I) falls within the field of view of the infrared camera 81. In step S803, the infrared camera 81 images this imaging point Ps(I) and obtains an image showing the imaging point Ps(I). In step S804, the control unit 100 confirms whether the specified pattern of the imaging point Ps(I) can be detected from the image by image processing, such as pattern recognition.

[0082] If the focus of the infrared camera 81 deviates from the imaging point Ps(I) and the specified pattern cannot be detected from the image ("NO" in step S804), the control unit 100 changes the 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 via 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 specified pattern is detected ("YES" in step S804).

[0083] In step S806, the control unit 100 calculates the position (X, Y, Z) of the imaging point Ps(I) based on the predefined 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 predefined 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 predefined pattern could be detected has been imaged.

[0084] In step S807, it is confirmed whether the count value I has reached the value 2 or not, i.e., whether the positions (X, Y, Z) of two pixels Ps(1) and Ps(2) have been determined. If the count value I is less than 2 ("NO" in step S807), the process returns to step S802 and executes steps S802 to S806. If the count value I is equal to 2 ("YES" in step S807), the process proceeds to step S808.

[0085] In step S808, a rotation angle θa is calculated for rotating the clamping platform 3 in the θ-direction such that a straight line passing through the two mapping points Ps(1) and Ps(2) is horizontal. If the difference to 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 platform 3 is rotated by the rotation angle θa (step S810), and the process returns to step S801. Steps S801 to S809 are performed in this manner.

[0086] If the difference to 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 image point Ps(3) using the infrared camera 81 and obtains an image that shows the image point Ps(3) in the same way as in step S803. In step S812, the control unit 100 confirms whether a predefined pattern contained in the image point Ps(3) can be detected from this image by image processing, such as pattern recognition.

[0087] If the specified 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 with the Z-axis camera motor 892 in the Z direction (step S813). Steps S811 to S813 are repeated until the specified pattern is detected (“YES” in step S812).

[0088] If the specified pattern can be detected in step S812 (JA), the control unit 100 calculates the position (X, Y, Z) of the mapping point Ps(3) based on the specified pattern detected from the image obtained by mapping the mapping point Ps(3) (step S814). In this way, the position (X, Y, Z) of each of the three mapping points Ps(1), Ps(2), and Ps(3) is obtained. In step S815, a plane passing through these three positions (X, Y, Z) is defined as the plane of the clamping platform 3, specifically the upper surface 311 of the suction plane 31.

[0089] In step S702 of the calibration of Fig. 13A will be the substrate level specification ( Fig. 13C). As in Fig. As shown in Figure 13C, during substrate plane specification, a count value I is reset to zero (step S901) to distinguish a plurality of (three) imaging points Pw(I) of the semiconductor substrate W, and the count value I is incremented by 1 (step S902). The imaging points Pw(I) are, for example, an area with a predefined pattern.

[0090] Specifically, the semiconductor substrate W is, as in Fig. Figure 12 shows the semiconductor substrate W in the form of a grid defined by planned division lines S (Sa, Sb) that are orthogonal to each other. This means that the semiconductor substrate W is provided with a plurality of planned division lines Sa parallel to each other and a plurality of planned division lines Sb parallel to each other, and the planned division lines Sa and Sb are orthogonal to each other. In this way, a plurality of semiconductor chips C are arranged in a grid over the planned division lines Sa and Sb. In contrast, a region containing an intersection of the planned division line Sa and the planned division line Sb (in other words, a point surrounded by the semiconductor chips C arranged at four corners) is defined as the mapping point Pw(I).Since the back of the semiconductor substrate W faces upwards as described above, the infrared camera 81 images the planned division lines Sa, Sb and the semiconductor chips C, which are formed on the front of the semiconductor substrate W, through the back of the semiconductor substrate W using infrared rays.

[0091] In step S903, the control unit 100 ensures that the imaging point Pw(I) of the infrared camera 81 is facing downwards by adjusting the position of the clamping stage 3 using 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 obtains an image showing the imaging point Pw(I). In step S904, the control unit 100 confirms whether a predefined pattern (for example, a cutting pattern of the planned division lines Sa, Sb) contained in the imaging point Pw(I) can be detected from this image by image processing, such as pattern recognition.

[0092] If the focus of the infrared camera 81 deviates from the imaging point Pw(I) and the specified pattern cannot be detected from the image ("NO" in step S904), the control unit 100 changes the 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 via 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 specified pattern is detected ("YES" in step S904).

[0093] It is noted that the plane (stage plane) representing the upper surface 311 of the suction plane 31 is defined 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, which is arranged on the suction plane 31, is present, 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 in a region in which the imaging point Pw(I) estimated from the stage plane is present.

[0094] In step S906, the control unit 100 calculates the position (X, Y, Z) of the imaging point Pw(I) based on the predefined pattern detected from the image obtained by imaging point Pw(I). The X and Y coordinates of the imaging point Pw(I) are calculated based on the position of the predefined 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 predefined pattern could be detected was captured.

[0095] In step S907, it is confirmed whether the count value I has reached the value 2 or not, i.e., whether the positions (X, Y, Z) of two pixels Ps(1) and Ps(2) have been determined. If the count value I is less than 2 ("NO" in step S907), the process returns to step S902 and executes steps S902 to S906. If the count value I is equal to 2 ("YES" in step S902), the process proceeds to step S908.

[0096] In step S908, a rotation angle Ob is calculated for the rotation of the clamping platform 3 in the θ-direction based on the two mapping points Pw(1) and Pw(2) such that the planned division lines Sa run parallel to the X-direction (machining direction). If the difference to 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 the process returns to step S901. Steps S901 to S909 are performed in this manner.

[0097] If the difference to 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 image point Pw(3) with the infrared camera 81 and obtains an image that shows the image point Pw(3) in the same way as in step S903. In step S912, the control unit 100 confirms whether a predefined pattern contained in the image point Pw(3) can be detected from this image by image processing, such as pattern recognition.

[0098] If the specified 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 via the Z-axis camera motor 892 (step S913). Steps S911 to S913 are repeated until the specified pattern is detected (“YES” in step S912). At this point, a range for changing the height of the infrared camera 81 is set based on the stage plane, as in the aforementioned case.

[0099] If the specified 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 specified pattern detected from the image obtained by 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 defined as representing the semiconductor substrate W.

[0100] Referring back to Fig. The description continues in section 11. If the semiconductor substrate W is positioned such that the planned division lines Sa are parallel to the X-direction, and the plane representing the semiconductor substrate W is determined by performing the calibration described above (step S601), the line processing (step S602) is performed for each planned division line Sa. This means that each of the plurality of planned division lines Sa is processed by the laser beam B by performing the line processing to direct the laser beam B onto the laser irradiation position Lb, while the laser irradiation position Lb is moved in the X-direction along the planned target division line Sa, while the planned target division line Sa is changed from the plurality of planned division lines Sa. In particular, as described in the section of step S602 of Fig. As shown in Figure 12, the line processing of moving the laser irradiation position Lb in the direction of (+X) in the X-direction and the line processing of moving the laser irradiation position Lb in the direction of the (-X) side in the X-direction are performed alternately.

[0101] At this point, the laser beam B is moved towards the (+X) side with respect to the planned division line Sa by driving the clamping platform 3, which holds the semiconductor substrate W, towards the (-X) side by the X-axis driver 65. Furthermore, the planned division line Sa of the line processing is changed by driving the clamping platform 3, which holds the semiconductor substrate W, in the Y direction by the Y-axis driver 63.The control unit 100 further performs a control to adjust the position in the Z-direction of the processing head 71 by the Z-axis head motor 792 based on the plane represented by the semiconductor substrate W, which was specified by the calibration of step S601. In this way, a focusing position of the laser beam B is adjusted within the semiconductor substrate W, and a modified layer is formed within the semiconductor substrate W along the planned division lines Sa.

[0102] When the line processing for each of the multiple planned division lines Sa is completed in this way (step S602), the clamping stage 3 holding the semiconductor substrate W is rotated 90° in the θ direction by the θ-axis table motor 66. This changes the state from one in which the multiple planned division lines Sa, on which the line processing has been carried out, are positioned parallel to the X direction (field “S602_e” of Fig. 12), to a state in which the multitude of planned division lines Sb are positioned parallel to the X direction (field “S603” of the Fig. 12).

[0103] In step S604, the calibration is performed as described in step S601 above. Furthermore, in step S605, the line processing for each of the multiple planned division lines Sb is performed as described in step S602 at the beginning.

[0104] Fig. Figure 14 is a flowchart showing a basic line processing process for each planned division line, and Fig. 15A shows diagrams that schematically illustrate a first example of a process, which follows the flowchart of Fig. 14 will be carried out. In Fig. Figure 15A shows a dotted line representing the laser irradiation position Lb moving relative to the semiconductor substrate W, and imaginary lines Sv1, Sv2, Sv3 extending parallel to the X-direction along the planned division lines S1, S2, S3 between the two outer sides of the planned division lines S1, S2, S3, are represented by a single-point catenary. It is noted that the dotted lines representing the laser irradiation position Lb's path are preferentially shown in the portions where the laser irradiation position Lb's path and the imaginary lines Sv1, Sv2, Sv3 intersect.

[0105] In the Fig. The example shown in 15A is the flowchart of Fig. 14. Starting from a state in which the laser irradiation position Lb is stopped at position Pb1 on the (-X) side of the semiconductor substrate W in the X direction. This position Pb1 is a position that is provided on the imaginary straight line Sv1 along the planned division line S1, in other words, that faces the planned division line S1 from the X direction. The position of the laser irradiation position Lb at the start of the flowchart of Fig. However, 14 is not limited to this example and can be modified as appropriate.

[0106] In step S1001, the laser irradiation position Lb, which is stopped at position Pb1, begins to accelerate in the X-direction towards the (+X) side and moves parallel to the X-direction. The laser irradiation position Lb moves along the imaginary straight line Sv1 towards the (+X) side. When the speed Vx of the laser irradiation position Lb increases to a processing speed Vxd by the time it reaches an end of the semiconductor substrate W on the (-X) side, the laser irradiation position Lb moves at the constant processing speed Vxd towards the (+X) side in the X-direction (step S1002).

[0107] Furthermore, the laser light source 72 is switched on and the irradiation of the laser beam B onto the laser irradiation position Lb from the processing head 71 is started at a time when the laser irradiation position Lb reaches the end of the semiconductor substrate W on the (-X) side (step S1003). Furthermore, the laser light source 72 is switched off and the irradiation of the laser beam B onto the laser irradiation position Lb from the processing head 71 is stopped at a time when 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 processing for the planned division line S1 is carried out by shining the laser beam B onto the laser irradiation position Lb while the laser irradiation position Lb is moved towards the (+X) side along the planned division line S1 (line processing).

[0108] When the laser irradiation position Lb passes through the planned division line S1 in the direction of the (+X) side, it begins to decelerate in the X direction (step S1005) and stops at position Pb2 on the (+X) side of the semiconductor substrate W in the X direction (step S1006). This position Pb2 is located on the imaginary line Sv2, which is adjacent to the imaginary line Sv1 in the Y direction; in other words, it faces the planned division 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 line Sv1 to the imaginary line Sv2, parallel to the deceleration in the X direction.

[0109] A positional relationship between the mapping areas Ri ( Fig. 1) The imaging sections 8A, 8B, and the laser irradiation position Lb of the processing head 71 are fixed. Therefore, in steps S1001 to S1006, the imaging sections Ri also move relative to the semiconductor substrate W when the laser irradiation position Lb moves relative to the semiconductor substrate W. When the laser irradiation position Lb is stopped at position Pb2, the imaging section Ri of imaging section 8B stops at a position that includes at least one imaging point Pw(S2). This imaging point Pw(S2) is an intersection point where the planned division line S2 and the planned division line S intersect orthogonally to the line S2 in the semiconductor substrate W. Accordingly, in step S1006, the control unit 100 causes imaging section 8B to image the imaging section Ri and obtain an image that includes the imaging point Pw(S2).This allows the control unit 100 to obtain an image showing the position of the unprocessed planned division line S2.

[0110] Step S1007 confirms whether the laser processing for the multitude of planned division lines S parallel to the X direction is complete. If any of these planned division lines S remains unprocessed ("NO" in step S1007), the process returns to step S1001.

[0111] In the example of Fig. In step S1001, step 15A begins to accelerate the laser irradiation position Lb, which is stopped at position Pb2, in the X-direction towards the (-X) side and moves parallel to the X-direction. The laser irradiation position Lb moves along the imaginary straight line Sv2 towards the (-X) side. When the velocity Vx of the laser irradiation position Lb increases to the processing speed Vxd by the time it reaches the end of the semiconductor substrate W on the (+X) side, the laser irradiation position Lb moves at the constant processing speed Vxd towards the (-X) side in the X-direction (step S1002).

[0112] This results in a coincidence of a position at which the laser irradiation position Lb, which has traversed the planned division line S1 in the direction of the (+X) side, begins to decelerate (in other words, an X-coordinate at which the movement at constant speed in the direction of the (+X) side ends), and a position at which the laser irradiation position Lb, which is accelerating in the direction of the (-X) side towards the planned division line S, ceases to accelerate (in other words, an X-coordinate at which the movement at constant speed in the direction of the (-X) side begins). This means that the X-coordinate at which the movement at constant speed of the laser irradiation position Lb, which traverses the planned division line Sn, to which the line processing in the n tenThe rotation is to be carried out, has been completed, and the delay is started, and the X-direction, at which the laser irradiation position Lb, which is located at the planned division line Sn+1, to which the line processing in the (n+1) ten The events of the rotation, the movement, the acceleration ending, and the start of the movement at constant speed coincide.

[0113] Furthermore, the laser light source 72 is switched on, and the illumination of the laser beam B onto the laser irradiation position Lb from the processing head 71 is started at a time when the laser irradiation position Lb reaches the end of the semiconductor substrate W on the (+X) side (step S1003). The laser light source 72 is then switched off, and the illumination of the laser beam B onto the laser irradiation position Lb from the processing head 71 is stopped at a time when the laser irradiation position Lb reaches the end of the semiconductor substrate W on the (-X) side (step S1004). In this way, during the period from step S1003 to step S1004, laser processing for the planned division line S2 is carried out by shining the laser beam B onto the laser irradiation position Lb while the laser irradiation position Lb moves towards the (-X) side along the planned division line S2 (line processing).

[0114] When the laser irradiation position Lb passes through the planned division line S2 in the direction of the (-X) side, it begins to decelerate 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 located on the imaginary line Sv3 adjacent to the imaginary line Sv2 in the Y direction; in other words, it is opposite the planned division line S3 in the X direction. This means that in steps S1005 to S1006, the laser irradiation position Lb moves in the Y direction from the imaginary line Sv2 to the imaginary line Sv3 parallel to the deceleration in the X direction.

[0115] When the laser irradiation position Lb is stopped at position Pb3, the imaging area Ri of imaging unit 8A stops at a position that includes at least one imaging point Pw(S3). This imaging point Pw(S3) is an intersection of the planned division line S3 and the planned division line S orthogonal to this line S3 in the semiconductor substrate W. Accordingly, in step S1006, the control unit 100 causes imaging unit 8A to image the imaging area Ri and obtain an image that includes the imaging point Pw(S3). In this way, the control unit 100 can obtain an image showing the position of the unprocessed planned division line S3.

[0116] Steps S1001 to S1007 are repeated until it is confirmed that the line processing for the multitude of planned division lines S (S1, S2, S3, ...) parallel to the X direction is completed (“YES” in step S1007).

[0117] Next, a change in the speed of the laser irradiation position Lb is described with reference to a "change in speed in the X direction" and a "change in speed in the Y direction". Fig. As described in Figure 15A, the velocity Vx represents the speed at which the laser irradiation position Lb is moved in the X-direction relative to the semiconductor substrate W, and the velocity Vy represents the speed at which the laser irradiation position Lb is moved in the Y-direction relative to the semiconductor substrate W. Furthermore, the processing velocity Vxd represents the speed at which the laser irradiation position Lb is moved at a constant speed in the X-direction along the planned division line S (i.e., the velocity Vx), and is represented by an absolute value independent of whether the movement is towards the (+X) side or the (-X) side.

[0118] During line processing period Ts1 (steps S1002 to S1004), in which the line processing involves moving the laser beam B towards the (+X) side along the planned division line S1, the laser irradiation position Lb does not move in the Y direction while moving in the X direction at a constant processing speed Vxd. Furthermore, during line processing period Ts2 (steps S1002 to S1004), in which the line processing involves moving the laser beam B towards the (-X) side along the planned division line S2, the laser irradiation position Lb does not move in the Y direction while moving in the X direction at a constant processing speed Vxd.

[0119] During 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. This means that the X-axis driver 65 (processing axis driver) performs a reverse drive to move the laser irradiation position Lb to the planned division line S2 (second processing line) by accelerating the laser irradiation position Lb towards the (-X) side (step S1001), after decelerating and stopping the laser irradiation position Lb, which has passed the intended division line S1 (first processing line) in the direction of the (+X) side (first side), in the direction of the (+X) side in the X direction (processing direction) (step S1005).Parallel to this reverse drive, 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 in the X-direction outwards of the planned division line S1 along the planned division line S1 to the imaginary straight line Sv2 (second imaginary straight line) extended in the X-direction outside the planned division line S2 along the planned division line S2 (second processing line).

[0120] Specifically, the switching period Tc includes a delay period Td (step S1005) to decelerate the laser irradiation position Lb in the X-direction and an acceleration period Ta (step S1001) to accelerate the laser irradiation position Lb in the X-direction. Movement of the laser irradiation position Lb in the Y-direction occurs outside of the delay period Td and the acceleration period Ta during the delay period Td. Specifically, the movement of the laser irradiation position Lb in the Y-direction begins after the start of the delay period Td and ends before the end of the delay period Td. Furthermore, the laser irradiation position Lb does not move in the Y-direction during the acceleration period Ta.

[0121] In this case, a starting point gives the delay period Td a time at which the delay of the laser irradiation position Lb in the X direction begins (i.e., a reduction of the absolute value of the velocity Vx from the processing speed Vxd begins), and an end point gives the delay period Td a time at which the velocity of the laser irradiation position Lb in the X direction (i.e., the velocity Vx) becomes zero.A starting point of the acceleration period Ta indicates a time at which the acceleration of the laser irradiation position Lb in the X direction begins (in other words, an increase in the absolute value of the velocity Vx from zero begins), and an end point of the acceleration period Ta indicates a time at which the acceleration of the laser irradiation position Lb in the X direction is completed (in other words, a time at which the absolute value of the velocity Vx becomes the processing speed Vxd).

[0122] Furthermore, during a stop period Tt, which occurs during the transition from the acceleration period Ta to the deceleration period Td, both the velocity Vx of the laser irradiation position Lb in the X-direction and its velocity Vy in the Y-direction are set to zero, and the laser irradiation position Lb is stopped at position Pb2 with respect to the semiconductor substrate W. During this stop period Tt, the imaging regions Ri of imaging parts 8A and 8B are also stopped with respect to the semiconductor substrate W. Specifically, the imaging region Ri of imaging part 8B is located on the (-X) side of the laser irradiation position Lb, which is on the (+X) side of the semiconductor substrate W, and overlaps the semiconductor substrate W. Accordingly, the infrared camera 81 of imaging part 8B images a portion of the semiconductor substrate W that overlaps the imaging region Ri during the stop period Tt (step S1006).

[0123] Fig. 15B shows diagrams that schematically illustrate a second example of the process according to the flowchart of the Fig. 14. The notation in Fig. 15B is similar to the one in Fig. 15A. Also in Fig. 15B will perform laser processing sequentially for the planned division lines S1, S2, S3 according to the flowchart of Fig. 14 as in Fig. 15A carried out. Fig. However, 15B differs from Fig. 15A is to be laser-processed during the switching period Tc for changing the planned division line S. Accordingly, the following description focuses on the differences to Fig. 15A, and common operating parts are identified by appropriate reference symbols, and the description is omitted where appropriate.

[0124] When the laser irradiation position Lb passes through the planned division line S1 in the direction of the (+X) side, as soon as the laser processing for the planned division line S1 is complete, the laser irradiation position Lb begins to slow down in the X direction in the direction of the (+X) side (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 that is provided on the imaginary straight line Sv1. When the laser irradiation position Lb stops at position Pb2, the imaging area Ri of the imaging unit 8B stops at a position that includes at least one imaging point Pw(S2). Accordingly, in step S1006, the control unit 100 causes the imaging unit 8B to image the imaging area Ri and obtain an image that includes the imaging point Pw(S2).In this way, the control unit 100 can obtain the image showing the position of the unprocessed planned division line S2.

[0125] Subsequently, the laser irradiation position Lb, which was stopped at position Pb2, begins to accelerate in the X direction towards the (-X) side (step S1001). As the velocity Vx of the laser irradiation position Lb increases to the processing speed Vxd by the time it reaches the end of the semiconductor substrate W on the (+X) side, the laser irradiation position Lb moves at the constant processing speed Vxd towards the (-X) side in the X direction (step S1002). Furthermore, during the period between the start of the acceleration and the start of the constant motion, the laser irradiation position Lb moves at the processing speed Vxd in the Y direction from the imaginary line Sv1 to the imaginary line Sv2.This means that the laser irradiation position Lb moves in the Y-direction from the imaginary line Sv1 to the imaginary line Sv2 parallel to the acceleration in the X-direction during steps S1001 to S1002. In this way, the laser irradiation position Lb reaches the planned division line S2, and the line processing for the planned division line S2 can be started.

[0126] When the laser irradiation position Lb passes through the planned division line S2 in the direction of the (-X) side, as soon as the laser processing for the planned division line S2 is complete, the laser irradiation position Lb begins to decelerate in the X direction in the direction of the (-X) side (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 that is provided on the imaginary straight line Sv2. When the laser irradiation position Lb stops at position Pb3, the imaging area Ri of the imaging unit 8A stops at a position that includes at least one imaging point Pw(S3). Accordingly, in step S1006, the control unit 100 causes the imaging unit 8A to image the imaging area Ri and obtain an image that includes the imaging point Pw(S3).In this way, the control unit 100 can obtain the image showing the position of the unprocessed planned division line S3.

[0127] Next, a change in the speed of the laser irradiation position Lb is described with reference to a "change in speed in the X direction" and a "change in speed in the Y direction". Fig. As described in section 15B, during a line processing period Ts1 (steps S1002 to S1004), in which the line processing involves moving the laser beam B towards the (+X) side along the planned division line S1, the laser irradiation position Lb does not move in the Y direction while moving in the X direction at a constant processing speed Vxd. Furthermore, during a line processing period Ts2 (steps S1002 to S1004), in which the line processing involves moving the laser beam B towards the (-X) side along the planned division line S2, the laser irradiation position Lb does not move in the Y direction while moving in the X direction at a constant processing speed Vxd.

[0128] Furthermore, during a switching period Tc (steps S1005, S1006, and S1001), during 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 line Sv1 to the imaginary line Sv2, parallel to the execution of the reverse drive 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, which consists of a deceleration period Td and the acceleration period Ta contained within the switching period Tc. Specifically, the movement of the laser irradiation position Lb in the Y-direction is started after the beginning of the acceleration period Ta, and the movement of the laser irradiation position Lb in the Y-direction is terminated before the end of the acceleration period Ta.Furthermore, the laser irradiation position Lb does not move in the Y direction during the delay period Td.

[0129] Furthermore, during a stop period Tt, which occurs during the transition from the acceleration period Ta to the deceleration period Td, both the velocity Vx of the laser irradiation position Lb in the X-direction and its velocity Vy in the Y-direction are set to zero, and the laser irradiation position Lb is stopped at position Pb2 with respect to the semiconductor substrate W. During this stop period Tt, the imaging regions Ri of imaging parts 8A and 8B are also stopped with respect to the semiconductor substrate W. Specifically, the imaging region Ri of imaging part 8B is located on the (-X) side of the laser irradiation position Lb, which is on the (+X) side of the semiconductor substrate W, and overlaps the semiconductor substrate W. Accordingly, the infrared camera 81 of imaging part 8B images a portion of the semiconductor substrate W that overlaps the imaging region Ri during the stop period Tt (step S1006).

[0130] Fig. Figure 15C schematically shows a third example of a process that follows the flowchart from Fig. 14 is carried out. The notation in Fig. 15C is similar to the one in Fig. 15A. Also in Fig. 15C will perform laser processing sequentially for the planned division lines S1, S2, S3 according to the flowchart of Fig. 14 as in Fig. 15A carried out. Fig. However, 15C differs from Fig. 15A through the process during the switching period Tc to switch the planned division line S, which is to be processed with the laser. Accordingly, the following description focuses on the differences to Fig. 15A, and common operating parts are identified by appropriate reference symbols, and the description is omitted where appropriate.

[0131] When the laser irradiation position Lb passes through the planned division line S1 in the direction of the (+X) side, as soon as the laser processing for the planned division line S1 is complete, the laser irradiation position Lb begins to decelerate 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 between the imaginary 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 line Sv1 to position Pb2 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 that includes at least one imaging point Pw (S2).Accordingly, in step S1006, control unit 100 instructs mapping unit 8B to map the mapping area Ri and obtain an image that includes the mapping point Pw (S2). In this way, control unit 100 can obtain the image showing the position of the unprocessed planned division line S2.

[0132] Subsequently, the laser irradiation position Lb, which was stopped at position Pb2, begins to accelerate in the X direction towards the (-X) side (step S1001). When the velocity Vx of the laser irradiation position Lb increases to the processing speed Vxd by the time it reaches the end of the semiconductor substrate W on the (+X) side, the laser irradiation position Lb moves at the constant processing speed Vxd towards the (-X) side in the X direction (step S1002). Furthermore, during the period between the start of the acceleration and the start of the constant motion, the laser irradiation position Lb moves at the processing speed Vxd in the Y direction from position Pb2 to the imaginary straight line Sv2.This means that the laser irradiation position Lb moves in the Y-direction from position Pb2 to the imaginary line Sv2 parallel to the acceleration in the X-direction in steps S1001 to S1002. In this way, the laser irradiation position Lb reaches the planned division line S2 and the line processing for the planned division line S2 can be started.

[0133] When the laser irradiation position Lb passes through the planned division line S2 in the direction of the (-X) side, as soon as the laser processing for the planned division line S2 is complete, the laser irradiation position Lb begins to decelerate 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 located between the imaginary line Sv2 and the imaginary line Sv3. This means that in steps S1005 to S1006, the laser irradiation position Lb moves in the Y direction from the imaginary line Sv2 to position Pb3 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 that includes at least the imaging point Pw (S3).Accordingly, in step S1006, control unit 100 instructs mapping unit 8A to map the mapping area Ri and obtain an image that includes the mapping point Pw (S3). In this way, control unit 100 can obtain the image showing the position of the unprocessed planned division line S3.

[0134] Next, a change in the speed of the laser irradiation position Lb is described with reference to a "change in speed in the X direction" and a "change in speed in the Y direction". Fig. As described in section 15C, during a line processing period Ts1 (steps S1002 to S1004), in which the line processing involves moving the laser beam B towards the (+X) side along the planned division line S1, the laser irradiation position Lb does not move in the Y direction while moving in the X direction at a constant processing speed Vxd. Furthermore, during a line processing period Ts2 (steps S1002 to S1004), in which the line processing involves moving the laser beam B towards the (-X) side along the planned division line S2, the laser irradiation position Lb does not move in the Y direction while moving in the X direction at a constant processing speed Vxd.

[0135] Furthermore, during 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 line Sv1 to the imaginary line Sv2, parallel to the execution of the reverse drive in the X-direction as in the aforementioned case. This movement of the laser irradiation position Lb is carried out specifically via position Pb2. This means that the laser irradiation position Lb moves in the Y-direction from the imaginary line Sv1 to position Pb2, within a deceleration period Td, and an acceleration period Ta, which is contained within the switching period Tc, and then moves in the Y-direction from position Pb2 to the imaginary line Sv2 during the acceleration period Ta.In particular, the laser irradiation position Lb begins to move from the imaginary line Sv1 to position Pb2 simultaneously with the start of the delay period Td, and reaches position Pb2 simultaneously with the end of the delay period Td. Furthermore, the laser irradiation position Lb begins to move from position Pb2 to the imaginary line Sv2 simultaneously with the start of the acceleration period Ta, and reaches the imaginary line Sv2 simultaneously with the end of the acceleration period Ta.

[0136] Furthermore, during a stop period Tt, which occurs during the transition from the acceleration period Ta to the deceleration period Td, both the velocity Vx of the laser irradiation position Lb in the X-direction and its velocity Vy in the Y-direction are set to zero, and the laser irradiation position Lb is stopped at position Pb2 with respect to the semiconductor substrate W. During this stop period Tt, the imaging regions Ri of imaging parts 8A and 8B are also stopped with respect to the semiconductor substrate W. Specifically, the imaging region Ri of imaging part 8B is located on the (-X) side of the laser irradiation position Lb, which is on the (+X) side of the semiconductor substrate W, and overlaps the semiconductor substrate W. Accordingly, the infrared camera 81 of imaging part 8B images a portion of the semiconductor substrate W that overlaps the imaging region Ri during the stop period Tt (step S1006).

[0137] It is noted that the specific manner in which the laser irradiation position Lb is moved from position Pb2 to the imaginary line Sv2 in the Y-direction after moving the laser irradiation position Lb from the imaginary line Sv1 to position Pb2 in the Y-direction during the switching period Tc does not apply to the example of the Fig. 15C is limited, and the movement is limited to the in Fig. 15D, Fig. 15E and Fig. 15F can be carried out in the manner shown.

[0138] Fig. 15D shows diagrams that schematically illustrate a fourth example of the process, as described in the flowchart of Fig. 14 is carried out, Fig. 15E shows diagrams that schematically illustrate a fifth example of the process, which, according to the flowchart of Fig. 14 is carried out and Fig. Figure 15F shows diagrams that schematically illustrate a sixth example of the process, as described in the flowchart of Fig. 14 is carried out. The designations in the Fig. 15D to 15F are similar to those in Fig. 15C. Fig. 15D to 15F differ from Fig. 15C through a movement mode of the laser irradiation position Lb during the switching period Tc. Accordingly, the following description focuses on the differences to Fig. 15C, and common operating parts are identified by appropriate reference symbols, and the description is omitted where appropriate.

[0139] In the Fig. In the fourth example shown in Figure 15D, the laser irradiation position Lb begins to move in the Y-direction from the imaginary line Sv1 to position Pb2 simultaneously with the start of the deceleration period Td, reaches position Pb2, and stops at position Pb2 in the Y-direction (i.e., the velocity Vy is zero) before the end of the deceleration period Td. However, after the laser irradiation position Lb reaches position Pb2 in the Y-direction, the deceleration period Td continues, and the laser irradiation position Lb continues to move in the X-direction. Furthermore, after the start of the acceleration period Ta, the laser irradiation position Lb begins to move in the Y-direction from position Pb2 to the imaginary line Sv2 and reaches the imaginary line Sv2 simultaneously with the end of the acceleration period Ta.This means that during 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 (i.e., the velocity Vy is zero).

[0140] In the fifth, in Fig. In the example shown in Figure 15E, the laser irradiation position Lb begins to move in the Y-direction from the imaginary line Sv1 to position Pb2 simultaneously with the start of the deceleration period Td, reaches position Pb2, and stops at position Pb2 in the Y-direction before the end of the deceleration period Td (i.e., the velocity Vy is zero). However, after the laser irradiation position Lb reaches position Pb2 in the Y-direction, the deceleration period Td continues, and the laser irradiation position Lb continues to move in the X-direction. Furthermore, the laser irradiation position Lb begins to move in the Y-direction from position Pb2 to the imaginary line Sv2 simultaneously with the start of the acceleration period Ta, and reaches the imaginary line Sv2 simultaneously with the end of the acceleration period Ta.This means that the laser irradiation position Lb is stopped in the Y direction for a period ΔTy from the middle of the deceleration period Td to the beginning of the acceleration period Ta (i.e. the velocity Vy is zero).

[0141] In the fifth, in Fig. In the example shown in Figure 15F, the laser irradiation position Lb begins moving in the Y-direction from the imaginary line Sv1 to position Pb2 simultaneously with the start of the delay period Td. However, the laser irradiation position Lb has not yet reached position Pb2 in the Y-direction at the end of the delay period Td. It is noted that at the end 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 position Pb2 coincide in the X-direction. Accordingly, the laser irradiation position Lb continues to move in the Y-direction towards position Pb2 even after the end of the delay period Td. Furthermore, the laser irradiation position Lb is stopped in the X-direction (i.e., the velocity Vx is zero) while the laser irradiation position Lb continues to move towards 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 position Pb2 to the imaginary line Sv2 as soon as the laser irradiation position Lb reaches position Pb2. Furthermore, the laser irradiation position Lb reaches the imaginary line Sv2 simultaneously with the end of the acceleration period Ta.

[0142] Fig. Figure 15G schematically shows a seventh example of a process, which, according to the flowchart of Fig. 14 is carried out. The notation in Fig. 15G is similar to the one in Fig. 15A. Also in Fig. 15G will perform laser processing sequentially for the planned division lines S1, S2, S3 according to the flowchart of Fig. 14 as in Fig. 15A was carried out. However, it differs. Fig. 15G of Fig. 15A through the process during the switching period Tc to change the planned division line S that is to be laser-processed. Accordingly, the following description focuses on the differences to Fig. 15A, and common operating parts are identified by appropriate reference symbols, and the description is omitted where appropriate.

[0143] When the laser irradiation position Lb passes through the planned division line S1 towards the (+X) side, as soon as the laser processing for the planned division line S1 is complete, the laser irradiation position Lb begins to decelerate 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 line Sv1 and the imaginary line Sv2 (on the side opposite the imaginary line Sv1 with respect to the imaginary line 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 line Sv1 to position Pb2, extending beyond the imaginary 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 imaging unit 8B stops at a position that includes at least one imaging point Pw(S3). Accordingly, in step S1006, the control unit 100 causes imaging unit 8B to image the imaging area Ri and obtain an image that includes the imaging point Pw(S3). In this way, the control unit 100 can obtain the image showing the position of the unprocessed planned division line S3.

[0144] Subsequently, the laser irradiation position Lb, which was stopped at position Pb2, begins to accelerate in the X direction towards the (-X) side (step S1001). When the velocity Vx of the laser irradiation position Lb increases to the processing speed Vxd by the time it reaches the end of the semiconductor substrate W on the (+X) side, the laser irradiation position Lb moves at the constant processing speed Vxd towards the (-X) side in the X direction (step S1002). Furthermore, during the period between the start of the acceleration and the start of the constant motion, the laser irradiation position Lb moves at the processing speed Vxd in the Y direction from position Pb2 to the imaginary straight line Sv2.This means that the laser irradiation position Lb moves in the Y-direction from position Pb2 to the imaginary line Sv2 parallel to the acceleration in the X-direction in steps S1001 to S1002. In this way, the laser irradiation position Lb reaches the planned division line S2 and the line processing for the planned division line S2 can be started.

[0145] When the laser irradiation position Lb passes through the planned division line S2 in the direction of the (-X) side, once the laser processing for the planned division line S2 is complete, the laser irradiation position Lb begins to decelerate in the X direction in the direction of the (-X) side (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 located outside a zone between the imaginary line Sv2 and the imaginary line Sv3 (on a side opposite the imaginary line Sv2 with respect to the imaginary line Sv3) in the Y direction. This means that the laser irradiation position Lb moves in the Y direction from the imaginary line Sv2 to the position Pb2 beyond the imaginary line Sv3 in steps S1005 to S1006, 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 unit 8A stops at a position that includes at least one imaging point Pw(S4). Accordingly, in step S1006, the control unit 100 causes the imaging unit 8A to image the imaging area Ri and obtain an image that includes the imaging point Pw(S4). In this way, the control unit 100 can obtain the image that shows the position of an unprocessed planned division line S4.

[0146] Next, a change in the speed of the laser irradiation position Lb is described with reference to a "change in speed in the X direction" and "change in speed in the Y direction". Fig. As described in section 15G, during a line processing period Ts1 (steps S1002 to S1004), in which the line processing involves moving the laser beam B towards the (+X) side along the planned division line S1, the laser irradiation position Lb does not move in the Y direction while moving in the X direction at a constant processing speed Vxd. Furthermore, during a line processing period Ts2 (steps S1002 to S1004), in which the line processing involves moving the laser beam B towards the (-X) side along the planned division line S2, the laser irradiation position Lb does not move in the Y direction while moving in the X direction at a constant processing speed Vxd.

[0147] Furthermore, during 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 line Sv1 to the imaginary line Sv2, parallel to the execution of the reverse drive in the X-direction as in the aforementioned case. In particular, this movement of the laser irradiation position Lb occurs via the position Pb2, which lies outside the zone between the imaginary line Sv1 and the imaginary line Sv2 in the Y-direction.This means that the laser irradiation position Lb moves in the Y-direction from the imaginary line Sv1 to the position Pb2 beyond the imaginary line Sv2, during a delay period Td, outside of the delay period Td and an acceleration period Ta, which is contained within the switching period Tc, and moves in the Y-direction from the position Pb2 to the imaginary line Sv2 during the acceleration period Ta. Specifically, the laser irradiation position Lb begins moving from the imaginary line Sv1 to the position Pb2 simultaneously with the start of the delay period Td and reaches the position Pb2 simultaneously with the end of the delay period Td. Furthermore, the laser irradiation position Lb begins moving from the position Pb2 to the imaginary line Sv2 simultaneously with the start of the acceleration period Ta and reaches the imaginary line Sv2 simultaneously with the end of the acceleration period Ta.

[0148] Furthermore, during a stop period Tt, which occurs during the transition from the acceleration period Ta to the deceleration period Td, both the velocity Vx of the laser irradiation position Lb in the X-direction and its velocity Vy in the Y-direction are set to zero, and the laser irradiation position Lb is stopped at position Pb2 with respect to the semiconductor substrate W. During this stop period Tt, the imaging regions Ri of imaging parts 8A and 8B are also stopped with respect to the semiconductor substrate W. Specifically, the imaging region Ri of imaging part 8B is located on the (-X) side of the laser irradiation position Lb, which is on the (+X) side of the semiconductor substrate W, and overlaps the semiconductor substrate W. Accordingly, the infrared camera 81 of imaging part 8B images a portion of the semiconductor substrate W that overlaps the imaging region Ri during the stop period Tt (step S1006).

[0149] In the example above, position Pb2 is located on the side opposite the imaginary line Sv1 with respect to the imaginary line Sv2 in the Y-direction. However, position Pb2 can also be located on a side opposite the imaginary line Sv2 with respect to the imaginary line Sv1 in the Y-direction. In this case, the laser irradiation position Lb moves in the Y-direction from the imaginary line Sv1 to position Pb2 during the deceleration period Td, and in the Y-direction from position Pb2 to the imaginary line Sv2 beyond the imaginary line Sv1 during the acceleration period Ta. A similar change can also be made for position Pb3.

[0150] Fig. Figure 16 is a flowchart that shows a first application example of line processing for each planned division line, and Fig. 17 is a diagram that schematically shows an example of a process that follows the flowchart of Fig. 16 is carried out. The designations in Fig. 17 are similar to those in the Fig. 15A to 15G. The example of Fig. 16 differs from the example of Fig. 14 by the presence of step S1008 of the representation of the semiconductor substrate W during line processing, but the other steps S1001 to S1007 are the same. Accordingly, in the example of Fig. 16 each of those in Fig. The processes shown in sections 15A to 15G (first to seventh example) were carried out. It is noted that, although a trace of the laser irradiation position Lb is present during the switching period Tc, Fig. 17 is not shown, the laser irradiation position Lb is located along the line in one of the Fig. can move along the track shown from 15A to 15G.

[0151] Step S1008 of Fig. Step 16 is performed as follows. This means that the semiconductor substrate W is imaged during a movement of the laser irradiation position Lb along the planned division 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) towards which the laser irradiation position Lb is moving, is imaged relative to the laser irradiation position Lb moving towards the (+X) side. In this way, an image is obtained that includes an imaging point Pw(S11) on the moving side of the laser irradiation position Lb relative to the laser irradiation position Lb. This allows an image to be obtained showing the position of an unprocessed part from the planned division line S1 that is currently being machined.

[0152] This means that during the period in which steps S1003, S1108 and S1104 are carried out, the image of the unprocessed part of the planned division line S1, which is to be line-processed, is captured in parallel with the execution of the line processing for the planned division line S1.

[0153] Furthermore, the semiconductor substrate W is imaged during a movement of the laser irradiation position Lb along the planned division 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) towards which the laser irradiation position Lb is moving, is imaged relative to the laser irradiation position Lb moving towards the (-X) side. In this way, an image is obtained that includes an imaging point Pw(S21) on the moving side of the laser irradiation position Lb relative to the laser irradiation position Lb. This allows an image to be obtained showing the position of an unprocessed part from the planned division line S2, which is currently being machined.

[0154] This means that during the period in which steps S1003, S1108 and S1104 are carried out, the image of the unprocessed part of the planned division line S2, which is to be line-processed, is captured in parallel with the execution of the line processing for the planned division line S2.

[0155] Furthermore, the semiconductor substrate W is imaged during a movement of the laser irradiation position Lb along the planned division 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) towards which the laser irradiation position Lb is moving, is imaged relative to the laser irradiation position Lb moving towards the (+X) side. In this way, an image is obtained that includes an imaging point Pw(S31) on the moving side of the laser irradiation position Lb relative to the laser irradiation position Lb. This allows an image to be obtained showing the position of an unprocessed part of the planned division line S3, which is currently being machined.

[0156] This means that during the period in which steps S1003, S1108 and S1104 are carried out, the image of the unprocessed part from the planned division line S3, which is to be line-processed, is captured in parallel with the execution of the line processing for the planned division line S3.

[0157] Steps S1001 to S1007 are repeated until it is confirmed that the line processing for the multitude of planned division lines S (S1, S2, S3, ...) parallel to the X direction is completed (“YES” in step S1007).

[0158] Fig. Figure 18 is a flowchart showing a second application example of line processing for each planned division line, and Fig. 19A shows diagrams that schematically illustrate a first example of a process, which follows the flowchart of Fig. 18 will be carried out. In Fig. Figure 19A shows a dotted line representing the laser irradiation position Lb moving relative to the semiconductor substrate W, and a single-point catenary representing the imaginary lines Sv1, Sv2, Sv3 extending parallel to the X-direction along the planned division lines S1, S2, S3 between the two outer sides of the planned division lines S1, S2, S3. It is noted that dotted lines representing the laser irradiation position Lb's path are preferentially shown in sections where the laser irradiation position Lb's path and the imaginary lines Sv1, Sv2, Sv3 intersect.

[0159] In the Fig. The example shown in 19A is the flowchart of Fig. 18 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 that is provided on the imaginary straight line Sv1 along the planned division line S1, in other words, that faces the planned division line S1 from the X direction. The position of the laser irradiation position Lb, when the flowchart of Fig. The fact that it starts on 18 is not limited to this example and can be modified as appropriate.

[0160] In step S1101, the laser irradiation position Lb, which is stopped at position Pb1, begins to accelerate in the X-direction towards the (+X) side and moves parallel to the X-direction. In this way, the laser irradiation position Lb moves along the imaginary straight line Sv1 towards the (+X) side. When the velocity Vx of the laser irradiation position Lb increases to the processing speed Vxd by the time it reaches the end of the semiconductor substrate W on the (-X) side, the laser irradiation position Lb moves at the constant processing speed Vxd in the X-direction towards the (+X) side (step S1102).

[0161] Furthermore, the laser light source 72 is switched on and the irradiation of the laser beam B onto the laser irradiation position Lb by the processing head 71 is started at a time when the laser irradiation position Lb reaches the end of the semiconductor substrate W on the (-X) side (step S1103). In this way, the laser beam B is directed onto the laser irradiation position Lb, which moves towards the (+X) side in the X direction along the planned parting line S1, thereby processing the planned parting line S1 (line processing).

[0162] Furthermore, in this example, the semiconductor substrate W is imaged during the movement of the laser irradiation position Lb along the planned division 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) towards which the laser irradiation position Lb is moving, is imaged relative to the laser irradiation position Lb moving towards the (+X) side. In this way, an image is obtained that includes an imaging point Pw(S11) on the moving side of the laser irradiation position Lb relative to the laser irradiation position Lb. This allows an image to be obtained showing the position of an unprocessed part from the planned division line S1 that is currently being machined.

[0163] Then the laser light source 72 is switched off and the laser beam B is directed onto the laser irradiation position Lb from the processing head 71 at a time when the laser irradiation position Lb reaches the end of the semiconductor substrate W on the (+X) side (step S1105). In this way, during the period from step S1103 to step S1105, the image of the unprocessed part from the planned parting line S1, which is to be processed, is acquired, in parallel with the execution of the line processing for the planned parting line S1.

[0164] When the laser irradiation position Lb passes through the planned division line S1 in the direction of the (+X) side, the laser irradiation position Lb begins to slow down in the X direction in the direction of the (+X) side (step S1106). In step S1107, it is confirmed whether the laser processing for the multitude of planned division lines S parallel to the X direction is complete or not. If there is an unprocessed planned division line S among these planned division lines S (“NO” in step S1107), the process returns to step S1101.

[0165] As a result, the laser irradiation position Lb is accelerated in the X-direction towards the (-X) side (step S1101) after the velocity Vx in the X-direction of the laser irradiation position Lb, which has slowed down towards the (+X) side, has become zero in the X-direction. When the velocity 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 at the constant processing speed Vxd towards the (-X) side in the X-direction (step S1102).

[0166] As just described, the same applies to the example of the Fig. 18 and Fig. 19A The reverse drive in the X-direction is as in the aforementioned case. Parallel to this reverse drive, the laser irradiation position Lb moves in the Y-direction from the imaginary line Sv1 to the imaginary line Sv2. In this way, the laser irradiation position Lb reaches the planned division line S2 by moving in the Y-direction towards the imaginary line Sv2 as soon as the velocity Vx in the X-direction of the laser irradiation position Lb increases to the processing speed Vxd.

[0167] In this example, however, the movement mode in the Y-direction of the laser irradiation position Lb differs from the one mentioned earlier. This means that the laser irradiation position Lb moves continuously in the Y-direction from a planned division line Sb1 to a planned division 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 throughout the entire time before and after the point at which the velocity 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 point at which both the velocity Vx in the X-direction of the laser irradiation position Lb and its velocity Vy in the Y-direction become zero.

[0168] The laser light source 72 is switched on and the irradiation of the laser beam B to the laser irradiation position Lb from the processing head 71 is started at a time when the laser irradiation position Lb reaches the end of the semiconductor substrate W on the (+X) side (step S1103). In this way, the laser beam B is directed onto the laser irradiation position Lb, which moves towards the (-X) side in the X direction along the planned parting line S2, and the planned parting line S2 is processed (line processing).

[0169] Furthermore, in this example, the semiconductor substrate W is imaged during the movement of the laser irradiation position Lb along the planned division 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) towards which the laser irradiation position Lb is moving, is imaged relative to the laser irradiation position Lb moving towards the (-X) side. In this way, an image is obtained that includes an imaging point Pw (S21) on the moving side of the laser irradiation position Lb relative to the laser irradiation position Lb. This allows an image to be obtained showing the position of an unprocessed part from the planned division line S2 that is currently being machined.

[0170] The laser light source 72 is switched off and the irradiation of the laser beam B onto the laser irradiation position Lb from the processing head 71 is terminated at a time when the laser irradiation position Lb reaches the end of the semiconductor substrate W on the (-X) side (step S1105). In this way, during the period from step S1103 to step S1105, the image of the unprocessed part from the planned parting line S2, which is to be line-processed, is acquired in parallel with the execution of the line processing for the planned parting line S2.

[0171] When the laser irradiation position Lb passes through the planned division line S2 in the direction of the (-X) side, the laser irradiation position Lb begins to decelerate in the X direction in the direction of the (-X) side (step S1106). In step S1107, it is confirmed whether the line processing for the multitude of planned division lines S parallel to the X direction is complete or not. If there is any unprocessed planned division line S among these planned division lines S (“NO” in step S1107), the process returns to step S1101.

[0172] As a result, the laser irradiation position Lb accelerates in the X-direction towards the (+X) side (step S1101) after the velocity Vx in the X-direction of the laser irradiation position Lb, which had slowed down towards the (-X) side, has become zero. When the velocity 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 towards the (+X) side in the X-direction at the constant processing speed Vxd (step S1102).

[0173] At this point, as in the aforementioned case, the continuous feed drive in the Y-direction for the laser irradiation position Lb is carried out parallel to the reverse drive in the X-direction. In this way, the laser irradiation position Lb reaches the planned division line S3 by moving in the Y-direction onto the imaginary straight line Sv3 when the velocity Vx in the X-direction of the laser irradiation position Lb increases to the processing speed Vxd.

[0174] The laser light source 72 is switched on and the irradiation of the laser beam B to the laser irradiation position Lb from the processing head 71 is started at a time when the laser irradiation position Lb reaches the end of the semiconductor substrate W on the (-X) side (step S1103). In this way, the laser beam B is directed onto the laser irradiation position Lb, which moves towards the (+X) side in the X direction along the planned parting line S3, and the planned parting line S3 is processed (line processing).

[0175] Furthermore, in this example, the semiconductor substrate W is imaged during the movement of the laser irradiation position Lb along the planned division 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) towards which the laser irradiation position Lb is moving, is imaged relative to the laser irradiation position Lb moving towards the (+X) side. In this way, an image is obtained that includes an imaging point Pw (S31) on the moving side of the laser irradiation position Lb relative to the laser irradiation position Lb. This allows an image to be obtained showing the position of an unprocessed part from the planned division line S3, which is currently being machined.

[0176] Then the laser light source 72 is switched off and the irradiation of the laser beam B onto the laser irradiation position Lb from the processing head 71 is terminated at a time when the laser irradiation position Lb reaches the end of the semiconductor substrate W on the (+X) side (step S1105). In this way, during the period from step S1103 to step S1105, the image of the unprocessed part from the planned parting line S3, which is to be processed, is acquired in parallel with the execution of the line processing for the planned parting line S3.

[0177] Next, a change in the speed of the laser irradiation position Lb is described with reference to a "change in speed in the X direction" and a "change in speed in the Y direction". Fig. As described in section 19A, during a line processing period Ts1 (steps S1103 to S1105), in which the line processing involves moving the laser beam B towards the (+X) side along the planned division line S1, the laser irradiation position Lb does not move in the Y direction while moving in the X direction at a constant processing speed Vxd. Furthermore, during a line processing period Ts2 (steps S1103 to S1105), in which the line processing involves moving the laser beam B towards the (-X) side along the planned division line S2, the laser irradiation position Lb does not move in the Y direction while moving in the X direction at a constant processing speed Vxd.

[0178] Furthermore, during a switching period Tc (steps S1106, S1101), during which a switchover from line processing period Ts1 to line processing period Ts2 takes place, the following process is carried out. This means that the X-axis driver 65 (processing axis driver) performs the reverse drive to move the laser irradiation position Lb to the planned division line S2 (second processing line) by accelerating the laser irradiation position Lb towards the (-X) side (step S1101), after having slowed down and stopped the laser irradiation position Lb, which has passed the intended division line S1 (first processing line) towards the (+X) side (first side), in the X direction (processing direction) (step S1106).Parallel to 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), which extends in the X direction outside the planned division line S1, along the planned division line S1 to the imaginary straight line Sv2 (second imaginary straight line), which extends in the X direction outside the planned division line S2, continuously along the planned division line S2.

[0179] In particular, the control unit 100 controls the X-axis driver 65 and the Y-axis driver 63 such that the Y-axis driver 63 begins the continuous feed drive before the X-axis driver 65 stops the laser irradiation position Lb in the X-direction by reversing, and the Y-axis driver 63 ends the continuous feed drive after the X-axis driver 65 stops the laser irradiation position Lb in the X-direction by reversing. In this way, the Y-axis driver 63 moves the laser irradiation position Lb in the Y-direction within a timeframe in which the X-axis driver 65 stops the laser irradiation position Lb in the X-direction by reversing.

[0180] In other words, the switching period Tc includes a delay period Td (step S1006) to slow down the laser irradiation position Lb in the X-direction and an acceleration period Ta (step S1001) to accelerate 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) throughout the entire time before and after the transition period Tx from the delay period Td to the acceleration period Ta. It is noted that the laser irradiation position Lb is stopped in the X-direction during the transition period Tx (i.e., the velocity Vx is zero).

[0181] Fig. 19B shows diagrams that schematically illustrate 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 imaging part 8A), located on a moving side (i.e., the (+X) side) towards which the laser irradiation position Lb is moving, is imaged several times (twice in this example) relative to the laser irradiation position Lb, which is moving towards the (+X) side to perform line processing for the planned division line S1 (step S1104). In this way, two images are obtained, each with two pixels Pw(S11) and Pw(S12) on the moving side of the laser irradiation position Lb relative to the laser irradiation position Lb. This allows images to be obtained showing the positions of the unprocessed parts of the planned division line S1, which is currently being line processed.

[0182] Similarly, the imaging area Ri (i.e., the imaging area Ri of imaging part 8B), located on a moving side (i.e., the (-X) side) towards which the laser irradiation position Lb is moving, is imaged multiple times (twice in this example) relative to the laser irradiation position Lb, which is moving towards the (-X) side to perform line processing for the planned division line S2 (step S1104). This yields two images, each with two pixels Pw(S21) and Pw(S22), on the moving side of the laser irradiation position Lb relative to the laser irradiation position Lb. This allows images to be obtained showing the positions of the unprocessed parts of the planned division line S2, which is currently being line processed. Furthermore, imaging is also performed multiple times during line processing for the planned division line S3 (step S1104).

[0183] Fig. 20 is a diagram that schematically shows an example of an image of the semiconductor substrate that is produced in step S1008 of the Fig. 16 or step S1104 of the Fig. 18. In the examples above, an area containing the intersection of two planned, mutually orthogonal division lines S is imaged to obtain an image IM. Since the image IM is obtained while the imaging area Ri is moved in the X-direction with respect to the semiconductor substrate W, the luminance in the image IM is averaged in the X-direction. As a result, a high-luminance area extending parallel to the X-direction according to the planned division line S appears, along with low-luminance areas that have a lower luminance than the high-luminance area and extend parallel to the X-direction according to the semiconductor chips C. In particular, in the Y-direction, the high-luminance area is enclosed by two low-luminance areas.Therefore, the control unit 100 can confirm the position of the planned division line S in the Y direction based on the area of ​​high luminance that corresponds to the planned division line S.

[0184] In the embodiment described above, imaging element 8A (first imaging element) is provided for imaging the imaging area Ri (first imaging area) located on the (+X) side (first side) in the X direction (processing direction) with respect to the laser irradiation position Lb, and imaging element 8B (second imaging element) is provided for imaging the imaging area Ri (second imaging area) located on the (-X) side (second side) with respect to the laser irradiation position Lb in the X direction (processing direction). Imaging elements 8A and 8B image portions of the semiconductor substrate W that overlap the respective imaging areas Ri (steps S1006, S1008, and S1104). In this way, the state of the semiconductor substrate W on both sides of the laser irradiation position Lb in the X direction can be detected.

[0185] Furthermore, the control unit 100 performs the line processing (first line processing) of the processing of the planned division line S1 (first processing line) by moving the laser irradiation position Lb in the direction of the (+X) side in the X direction and the line processing (second line processing) of the processing of the planned division line S2 (second processing line) by moving the laser irradiation position Lb in the direction of the (-X) side in the X direction.

[0186] Furthermore, during the switching period Tc (first switching period) from the end of the line processing for the planned division line S1 to the beginning of the line processing for the planned division line S2, the X-axis driver 65 performs the reverse drive (first reverse drive) to move the laser irradiation position Lb to the planned division line S2 by accelerating the laser irradiation position Lb towards the (-X) side after the laser irradiation position Lb, which has passed through the planned division line S1 in the direction of the (+X) side, has been decelerated and stopped in the X direction (steps S1005, S1001).Furthermore, during this switching period Tc, the Y-axis driver 63 moves the laser irradiation position Lb in the Y-direction (feed direction) from the virtual straight line Sv1 (first imaginary straight line), which moves in the X-direction to outside the planned division line S1 along the planned division line S1, to the virtual straight line Sv2 (second imaginary straight line), which is extended in the X-direction outside the planned division line S2 along the planned division line S2. Additionally, during this switching period Tc, the imaging section 8B images the portion of the semiconductor substrate W that overlaps the imaging area Ri of the imaging section 8B (step S1006).In such a configuration, an image showing the state of the semiconductor substrate W on the (-X) side of the laser irradiation position Lb can be acquired by imaging part 8B, effectively using the switching time Tc to move the laser irradiation position Lb, which has passed through the planned division line S1, towards the planned division line S2.

[0187] Furthermore, the control unit 100 provides the stop period Tt (first stop period), during which the laser irradiation position Lb stops in both the X and Y directions. This is achieved by causing the Y-axis driver 63 to stop the laser irradiation position Lb at a time when the X-axis driver 65 stops the laser irradiation position Lb by reverse driving during the switching period Tc from line processing for the planned division line S1 to line processing for the planned division line S2. Then, the imaging section 8B maps the portion of the semiconductor substrate W that overlaps the imaging area Ri of the imaging section 8B during this stop period Tt.In such a configuration, a still image showing the state of the semiconductor substrate W on the (-X) side of the laser irradiation position Lb can be acquired by the imaging part 8B, effectively using the switching time Tc to move the laser irradiation position Lb, which has passed through the planned division line S1, towards the planned division line S2.

[0188] Furthermore, the control unit 100 again performs the line processing (third line processing) of the processing of the planned division line S2 (third processing line) by moving the laser irradiation position Lb in the X direction to the (-X) side, and the line processing (fourth line processing) of the processing of the planned division line S3 (fourth processing line) by moving the laser irradiation position Lb in the X direction to the (+X) side.During the switching period Tc (second switching period) from the end of the line processing for the planned division line S2 until the beginning of the line processing for the planned division line S3, the X-axis driver 65 performs the reverse drive (second reverse drive) to move the laser irradiation position Lb to the planned division line S3 by accelerating the laser irradiation position Lb towards the (+X) side after the laser irradiation position Lb, which has passed through the planned division line S2 in the direction of the (-X) side, has been decelerated and stopped in the X direction (steps S1005, S1001).Furthermore, during this switching period Tc, the Y-axis driver 63 moves the laser irradiation position Lb in the Y-direction from the virtual straight line Sv2 (third imaginary straight line) extended in the X-direction to the outside of the planned division line S2 along the planned division line S2 to the virtual straight line Sv3 (fourth imaginary straight line) extended in the X-direction to the outside of the planned division line S3 along the planned division line S3. Furthermore, during this switching period Tc, the imaging section 8A images the portion of the semiconductor substrate W that overlaps the imaging area Ri of the imaging section 8A (step S1006).In such a configuration, an image showing the state of the semiconductor substrate W on the (+X) side of the laser irradiation position Lb can be acquired by the imaging part 8A, effectively using the switching time Tc to move the laser irradiation position Lb, which has passed through the planned division line S2, towards the planned division line S3.

[0189] Furthermore, the control unit 100 provides the stop period Tt (second stop period), during which the laser irradiation position Lb stops in both the X and Y directions. This is achieved by causing the Y-axis driver 63 to stop the laser irradiation position Lb at a time when the X-axis driver 65 stops the laser irradiation position Lb by reversing the switching period Tc from the line processing for the planned division line S2 to the line processing for the planned division line S3. Then, the imaging section 8A maps the portion of the semiconductor substrate W that overlaps the imaging area Ri of the imaging section 8A during the stop period Tt (step S1006).In such a configuration, a still image showing the state of the semiconductor substrate W on the (+X) side of the laser irradiation position Lb can be acquired by the imaging section 8A, effectively using the switching period Tc to move the laser irradiation position Lb, which has passed through the planned division line S2, in the direction of the planned division line S3.

[0190] Furthermore, the imaging part 8A represents the part of the semiconductor substrate W that overlaps the imaging area Ri of the imaging part 8A during the execution of the line processing for the planned division line S1 (steps S1008, S1104), and the imaging part 8B represents the part of the semiconductor substrate W that overlaps the imaging area Ri of the imaging part 8B during the execution of the line processing for the planned division line S2 (steps S1008, S1104).In such a configuration, an image showing the state of the semiconductor substrate W on the (+X) side of the laser irradiation position Lb can be acquired by the imaging part 8A, using an execution period of the line processing for the planned division line S1, and an image showing the state of the semiconductor substrate W on the (-X) side of the laser irradiation position Lb can be acquired by the imaging part 8B, using an execution period of the line processing for the planned division line S2.

[0191] Fig. 21 is a flowchart showing an example of a method for determining laser processing conditions in line processing, Fig. 22A shows diagrams that illustrate parameters related to determining laser processing conditions, Fig. Figure 22B is a diagram showing the temporal influence of the laser processing condition, and Fig. 22C is a table that shows an example of a table that can be used when determining the laser processing conditions of Fig. Reference is made to 21. This table is pre-stored in memory 190.

[0192] Fig. Figure 22A shows an upper diagram representing the relationship between the velocity Vx of the laser irradiation position Lb moving in the X direction and time, and a lower diagram representing the relationship between the velocity Vx of the laser irradiation position Lb moving in the X direction and the position in the X direction (i.e. the X coordinate) of the laser irradiation position Lb during line processing.

[0193] As shown in the diagram below, to perform line processing for the planned division line S, an irradiation position scan is carried out to direct the laser beam B to the laser irradiation position Lb, which overlaps the planned division line S, while the laser irradiation position Lb is moved in the X-direction from a starting point Xs on one side of the planned division line S to an endpoint Xe on the other side (the side opposite one side) of the planned division line S. This means that during the irradiation position scan, the laser beam B is directed from the processing head 71 to the laser irradiation position Lb, which overlaps the planned division line S, while the laser irradiation position Lb is moved in the X-direction from the starting point Xs to the endpoint Xe by the X-axis driver 65. In this way, the aforementioned line processing is carried out according to the irradiation position scan.

[0194] In this irradiation position scan, a constant velocity zone SC is defined for the planned division line S. This constant velocity zone SC lies between the start point Xs and the endpoint Xe in the X-direction and is set to include the planned division line S. In this example, both ends of the constant velocity zone SC coincide with both ends of the planned division line S in the X-direction; in other words, the constant velocity zone SC coincides with the planned division line S. However, setting the constant velocity zone SC is not limited to this example, and the constant velocity zone SC can be set by adding offsets beyond the two ends of the planned division line S. In this case, the constant velocity zone SC becomes longer than the planned division line S.The offset length can be a predetermined fixed value or a value obtained by multiplying the length of the planned division line S by a predetermined scaling factor (for example, 1%). The length of such a constant-velocity zone SC is determined according to the length of the planned division line S. The longer the planned division line S, the longer the constant-velocity zone SC (in other words, the shorter the planned division line S, the shorter the constant-velocity zone SC).

[0195] During this irradiation position scanning, the laser irradiation position Lb moves in the X-direction from the starting point Xs, located on one side of the zone of constant velocity SC, to the endpoint X3, located on the other side of the zone of constant velocity SC. Furthermore, during the acceleration period Ta, while the laser irradiation position Lb moves in the X-direction from the starting point Xs to an endpoint Xss on one side of the zone of constant velocity SC in the X-direction, the laser irradiation position Lb is accelerated with an acceleration A in the X-direction, and the velocity Vx in the X-direction of the laser irradiation position Lb increases from zero to the processing speed Vxd.Furthermore, the laser irradiation position Lb moves in the X-direction from end Xss on one side of the constant velocity zone SC to end Xse on the other side of the constant velocity zone SC at a constant processing speed Vxd in the X-direction during a constant velocity period Tsc (which in this example coincides with the line processing period Ts). Additionally, during the deceleration period Tb, while the laser irradiation position Lb moves in the X-direction from end Xse on the other side of the constant velocity zone SC to endpoint Xe, it is decelerated by acceleration A in the X-direction, and the velocity Vx in the X-direction of the laser irradiation position Lb decreases from the processing speed Vxd to zero.

[0196] At this point in time, the acceleration period Ta is a period (Vxd / A) required to increase the velocity Vx from zero to the processing speed Vxd during acceleration A; the constant velocity period Tsc is a period (Lsc / Vxd) required to move at the processing speed Vxd a distance Lsc, which is the length of the zone of constant velocity SC; and the deceleration period Td is a period (Vxd / A) required to decrease the velocity Vx from the processing speed Vxd to zero during acceleration A. Therefore, the sampling time t required for irradiation position scanning is: t=2×Vxd / A+Lsc / Vxd. Thus, the in Fig. The relationship shown in 22B between the processing speed Vxd and the sampling time t is satisfied. This means that the sampling time t has a minimum value when the processing speed Vxd is Vxd_min (= (Lsc×A / 2) 1 / 2 ). Therefore, line processing can be carried out efficiently by setting the processing speed Vxd according to the length (constant speed section Lsc) of the constant speed zone SC.

[0197] However, if the processing speed Vxd is changed, the frequency of the laser beam B emitted from the laser light source 72 must also be changed. In particular, if the processing 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 is derived from Fig. 22C is used. This table specifies a relationship between the constant-velocity distance Lsc (length of the planned division line S in this example), the processing speed Vxd, and the frequency fc of the laser beam B. Specifically, the following laser processing conditions are defined in the table. If the constant-velocity distance Lsc is less than or equal to Lsc(1), the processing speed Vxd is set to Vxd(1) and the frequency of the laser beam B is set to fc(1). If the constant-velocity distance Lsc is greater than Lsc(1) and less than or equal to Lsc(2), the processing speed Vxd is set to Vxd(2) and the frequency of the laser beam B is set to fc(2).

[0198] This means that in the laser processing condition determination of Fig. 21. The length (constant velocity distance Lsc) of the constant velocity zone SC, which was defined for the planned division line S to be processed, is obtained (step S 1201). Then the processing speed Vxd is determined (step S 1202) and the frequency fc of the laser beam B is determined (step S 1203), based on the constant velocity distance Lsc obtained in step S 1201 and the table of Fig. 22C. The radiation position scanning is performed according to the guidelines provided by Fig. 21 laser processing conditions determined in this way (processing speed Vxd and frequency fc) were carried out.

[0199] The irradiation position scanning is performed sequentially for the multitude of planned division lines S parallel to the X-direction. In other words, a multitude of irradiation position scans are performed for the planned division lines S, each differing from the others. In contrast, the laser processing condition determination of Fig. 21 for each of the multitude of irradiation position scans. In each irradiation position scan, the laser irradiation position Lb is moved and the laser beam B is emitted according to the laser processing conditions determined for each irradiation position scan.

[0200] In particular, if the semiconductor substrate W, formed with a multitude of planned division lines S parallel to the X-direction, is circular as in the example above, the planned division line S becomes shorter the further it is from a circle's center in the Y-direction, and the constant velocity distance Lsc defined for the planned division line S also becomes shorter. This means that the constant velocity distance Lsc set for the irradiation position scan differs depending on the position of the planned division line S in the Y-direction for which the irradiation position scan is performed. Accordingly, it is advantageous to determine the laser processing conditions for each irradiation position scan performed sequentially for several planned division lines S.

[0201] It is noted that the laser processing condition determination can be performed at any time before the start of the irradiation position scanning, which is a goal of the laser processing condition determination. For example, the laser processing condition determination can be performed for all of the multiple irradiation position scans before the multiple irradiation position scans, each corresponding to the multiple planned division lines S parallel to the X direction, are started. Alternatively, if the next irradiation position scan is to be performed following an irradiation position scan, the laser processing condition determination for the next irradiation position scan can be performed while the current irradiation position scan is being executed.

[0202] It is noted that, as in Fig. Figure 22C shows that the processing speed Vxd is adjusted by selecting one of a variety of discrete processing speeds Vxd(1), Vxd(2), Vxd(3), and Vxd(4), and the oscillation frequency fc is adjusted by selecting one of a variety of discrete oscillation frequencies fc(1), fc(2), fc(3), and fc(4). This means that when determining the laser processing conditions, the processing speed Vxd and the oscillation frequency fc are selected based on which of the values ​​shown in Fig. The four regions shown in Figure 22C represent the constant velocity range Lsc. If, at this time, the regions to which the constant velocity range Lsc belongs are the same between two successive laser irradiation position scans performed when the processing speed Vxd and the oscillation frequency fc are set by executing the laser processing condition determination for each of the plurality of irradiation position scans, the processing speed Vxd and the oscillation frequency fc are maintained. On the other hand, the processing speed Vxd and the oscillation frequency fc are changed (i.e., switched) if the regions to which the constant velocity range Lsc belongs are different between two successive laser irradiation position scans.This means that setting the processing speed Vxd includes maintaining the processing speed Vxd and changing (switching) the processing speed Vxd, and setting the oscillation frequency fc includes maintaining the oscillation frequency fc and changing (switching) the oscillation frequency fc.

[0203] As just described, 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 to an example of a "support element" according to the invention, the Y-axis driver 63 to an example of a "feed axis driver" according to the invention, the X-axis driver 65 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 8A corresponds to an example of a "first imaging part" according to the invention, the imaging area Ri of the imaging part 8A corresponds to an example of a "first imaging area" according to the invention, the imaging part 8B corresponds to an example of a "second imaging part" according to the invention, and the imaging area Ri of the imaging part 8B corresponds to an example of a "second imaging area" 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 planned division line S corresponds to an example of a "processing line" according to the invention, the planned division line S1 corresponds to an example of a "first processing line" according to the invention, the planned division line S2 corresponds to an example of a "second processing line" according to the invention.The imaginary straight line Sv1 corresponds to an example of a “first imaginary straight line” according to the invention, the imaginary straight line Sv2 corresponds to an example of a “second imaginary straight line” according to the invention, the planned division line S2 corresponds to an example of a “third machining line” according to the invention, the planned division line S3 corresponds to an example of a “fourth machining line” according to the invention, the imaginary straight line Sv2 corresponds to an example of a “third imaginary straight line” according to the invention, the imaginary straight line Sv3 corresponds to an example of a “fourth imaginary straight line” according to the invention, the semiconductor substrate W corresponds to an example of a “machining object” according to the invention, the X-direction corresponds to an example of a “machining direction” according to the invention, the Y-direction corresponds to an example of a “feed direction” according to the invention,The (+X) side corresponds to an example of a "first side" according to the invention, and the (-X) side corresponds to an example of a "second side" according to the invention.

[0204] It is noted that the invention is not limited to the embodiment described above and that various modifications other than those described above can be made without departing from the spirit of the invention. For example, the use of the captured image in the embodiment described above is not specifically described. However, such an image can be used for various purposes. Accordingly, the control unit 100 can, based on the captured image of the semiconductor substrate W, calculate a displacement of the unprocessed planned division line S in the Y-direction and align the planned division line S to be processed, as well as the laser irradiation position Lb, based on this displacement.

[0205] Although in the examples above, the figure part 8 depicts the intersection of the two planned division lines S orthogonally to each other, an object to be depicted by figure part 8 is not limited to this and can, for example, be an alignment mark or the like attached to the semiconductor chip C.

[0206] Furthermore, the specific 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 can, for example, be a drive mechanism for driving the processing head 71 in the X and Y directions.

[0207] Furthermore, the individually separated semiconductor chips C can be processed using the laser processing method described above (substrate processing of Fig.11 or the like) are manufactured (semiconductor chip manufacturing process). In this semiconductor chip manufacturing process, a modified layer is formed by performing the line processing for the planned division lines S of the semiconductor substrate W using the laser processing method described above (laser processing step). Subsequently, each of the multitude of semiconductor chips C is separated by stretching and expanding the band E that holds the semiconductor substrate W (expansion step). REFERENCE MARK LIST 1 laser processing device 3 the tensioning platform (support element) 63 Y-axis drivers (feed axis drivers) 65 of the X-axis drivers (machining axis drivers) 71 Processing head 8A Illustration section (first illustration section) 8B Illustration section (second illustration section) 100 Control unit (computer) 191 Laser processing program 192 Recording medium QUOTES INCLUDED IN THE DESCRIPTION

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

[0000] JP 5804716

[0002] JP 5554593

[0002] 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 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; a first imaging part located on a first side in the machining direction with respect to the machining head and imaging a first imaging area located on the first side of the laser irradiation position; a second imaging part located on a second side opposite to the first side in the machining direction with respect to the machining head and imaging a second imaging area located on the second side of the laser irradiation position; and a control unit for machining the machining line by performing line machining by moving the laser irradiation position in the machining direction with respect to the machining object by the machining axis driver while irradiating the laser beam from the machining head to the laser irradiation position, the laser irradiation position being aligned with the machining line by the feed axis driver; and wherein the first imaging region and the second imaging region move relative to the processing object integrally with the laser irradiation position as soon as the laser irradiation position moves, and wherein the control unit causes the first imaging part to image a part of the processing object that overlaps the first imaging area and causes the second imaging part to image a part of the processing object that overlaps the second imaging area. [2] Laser processing apparatus according to claim 1, wherein: the control unit sequentially performs a first line processing of processing a first processing line among the plurality of processing lines by moving the laser irradiation position toward the first side in the processing direction, and a second line processing of processing a second processing line, different from the first processing line, among the plurality of processing lines by moving the laser irradiation position toward the second side in the processing direction. [3] Laser processing apparatus according to claim 2, wherein: the machining axis driver performs a first reverse drive to move the laser irradiation position to the second machining line by accelerating the laser irradiation position toward the second side after decelerating and stopping the laser irradiation position that has passed through the first machining line toward the first side in the machining direction toward the first side, and the feed axis driver moves the laser irradiation position in the feed direction from a first imaginary straight line extending in the machining direction to outside the first machining line along the first machining line to a second imaginary straight line extending in the machining direction to outside the second machining line along the second machining line, in a first switching period from the end of the first line machining to the start of the second line machining, and the second imaging part images the part of the processing object that overlaps the second imaging area in the first switching period. [4] Laser processing apparatus according to claim 3, wherein the control unit provides a first stop period during which the laser irradiation position stops in both the machining direction and the feed direction by causing the feed axis driver to stop the laser irradiation position at a time when the machining axis driver stops the laser irradiation position by the first reverse drive in the first switching period, and the second mapping part maps the part of the processing object that overlaps the second mapping area in the first stop period. [5] Laser processing apparatus according to claim 3 or 4, wherein: the control unit sequentially performs a third line processing of processing a third processing line from the plurality of processing lines by moving the laser irradiation position toward the second side in the processing direction, and a fourth line processing of processing a fourth processing line from the plurality of processing lines different from the third processing line by the line processing of moving the laser irradiation position toward the first side in the processing direction, the machining axis driver performs a second reverse drive to move the laser irradiation position to the fourth machining line by accelerating the laser irradiation position toward the first side after the laser irradiation position, which has passed through the third machining line toward the second side, has been decelerated and stopped toward the second side in the machining direction, and the feed axis driver moves the laser irradiation position in the feed direction in a second switching period from the end of the third line machining to the start of the fourth line machining, from a third imaginary straight line extending in the machining direction along the third machining line to the outside of the third machining line, to a fourth imaginary straight line extending in the machining direction along the fourth machining line to the outside of the fourth machining line,and, the first imaging part images a part of the processing object that overlaps the first imaging area in the second switching period. [6] Laser processing apparatus according to claim 5, wherein: the control unit provides a second stop period during which the laser irradiation position stops in both the machining direction and the feed direction by causing the feed axis driver to stop the laser irradiation position at a time when the machining axis driver stops the laser irradiation position by the second reverse drive in the second switching period, and the first mapping part maps the part of the processing object that overlaps the first mapping area in the second stop period. [7] Laser processing apparatus according to one of claims 2 to 6, wherein: the first mapping part maps the part of the processing object that overlaps the first mapping area during the execution of the first line processing, and the second image part depicts the part of the processing object that overlaps the second image area during the execution of the second line processing. [8] A laser machining method for machining a machining line of a machining object having a plurality of machining lines parallel to each other, comprising: Supporting the processing object by a support element so that the processing lines run parallel to a given processing direction; Moving a laser irradiation position in the machining direction with respect to the machining object by a machining axis driver for driving a machining head to irradiate a laser beam onto a predetermined laser irradiation position and / or the support member in the machining direction while the laser beam is irradiated from the machining head onto the laser irradiation position, wherein the laser irradiation position is aligned with the machining line by a feed axis driver for driving the machining head and / or the support member in a feed direction orthogonal to the machining direction; Imaging a first imaging region located on a first side of the laser irradiation position by a first imaging part arranged on the first side in the machining direction with respect to the machining head; and Imaging a second imaging region located on a second side of the laser irradiation position by a second imaging part arranged on the second side opposite the first side in the machining direction with respect to the machining head, wherein the first imaging region and the second imaging region move relative to the processing object integrally with the laser irradiation position when the laser irradiation position moves, wherein the first image part depicts a part of the processing object that overlaps the first image area, and wherein the second image portion depicts a portion of the processing object that overlaps the first image area. [9] A laser processing program for causing a computer to carry out the laser processing method according to claim 8. [10] A recording medium for computer-readably storing the laser processing program according to claim 9. [11] A semiconductor chip manufacturing method comprising: Processing a semiconductor substrate having a plurality of semiconductor chips defined by processing lines and arrayed in the semiconductor substrate by the laser processing method according to claim 9; 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. [12] Semiconductor chip manufactured by: Processing a semiconductor substrate having a plurality of semiconductor chips defined by processing lines and arrayed in the semiconductor substrate by the laser processing method according to claim 9; 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.

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