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

Abstract

The present invention involves capturing an image of a semiconductor substrate W by an imaging unit 8B for capturing an image of an imaging range Ri that moves relative to the semiconductor substrate W and integrally with a laser irradiation position Lb in association with a relative movement of the laser irradiation position Lb with respect to the semiconductor substrate W. In particular, the imaging range Ri is located on the (-X) side as compared with the laser irradiation position Lb in an X-direction. The imaging unit 8B captures an image of a portion (imaging point Pw) of the semiconductor substrate W overlapping the imaging range Ri during a change-over period Tc. Accordingly, the change-over period Tc is effectively used for imaging of the semiconductor substrate W. Consequently, it is possible to minimize the effect imposed by the change-over period Tc, during which the direction of movement of a laser beam B is switched, on the time required to complete machining of the semiconductor substrate W.

Description

[Technical field]

[0001] The present invention relates to a technique for processing a processing line provided on a processing object by irradiating the processing line with laser light. [Background technology]

[0002] Patent documents 1 to 3 describe a laser processing technique in which a dividing line provided on a semiconductor substrate is irradiated with a laser beam while the laser beam is moved relative to the semiconductor substrate to process the dividing line. For example, as shown in Patent document 1, in this laser processing technique, a plurality of dividing lines are processed in sequence by moving the laser beam back and forth while changing the dividing line to be irradiated with the laser beam in the forward and backward directions. At this time, the position of the laser beam is adjusted according to the result of an alignment process that recognizes the position of the dividing line based on an image acquired by imaging a predetermined portion of the semiconductor substrate, so that the dividing line can be accurately irradiated with the laser beam (Patent document 2). Also, as pointed out in Patent document 3, the width of the dividing line is expanded by processing the dividing line with the laser beam, and the position of the unprocessed dividing line may be shifted in the feed direction perpendicular to the processing direction. In order to deal with such a position shift of the dividing line, it is appropriate to appropriately perform imaging of the semiconductor substrate. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 5804716 [Patent Document 2] JP 5554593 A [Patent Document 3] JP 5037082 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the laser processing technique for sequentially processing a plurality of processing lines (planned division lines) provided on a processing object (semiconductor substrate) while moving a laser beam back and forth as described above, a switching period occurs for switching the movement of the laser beam between the forward path and the return path. Therefore, in order to efficiently process the processing object, it has been desired to suppress the influence of the switching period on the time required to complete processing of the processing object.

[0005] The present invention has been made in consideration of the above-mentioned problems, and aims to provide a technology in a laser processing technology in which the moving direction of a laser beam is switched between the forward and return sides to process a processing line of a workpiece, which makes it possible to reduce the effect that the switching period for switching the moving direction of a laser beam has on the time required to complete processing of the workpiece. [Means for solving the problem]

[0006] A laser processing apparatus according to a first aspect of the present invention includes a support member that supports a workpiece having a plurality of parallel processing lines so that the processing lines are parallel to a predetermined processing direction; a processing head that irradiates a laser beam to a predetermined laser irradiation position; a processing axis drive unit that drives at least one of the support member and the processing head in the processing direction to move the laser irradiation position relative to the workpiece in the processing direction; a feed axis drive unit that drives at least one of the support member and the processing head in a feed direction perpendicular to the processing direction to move the laser irradiation position relative to the workpiece in the feed direction; a control unit that processes the processing line by executing a line processing process in which the processing head irradiates the laser beam to the laser irradiation position in a state in which the laser irradiation position is aligned with the processing line by the feed axis drive unit, while moving the laser irradiation position in the processing direction relative to the workpiece by the processing axis drive unit; and an imaging unit that images a predetermined imaging range that moves relative to the workpiece integrally with the laser irradiation position as the laser irradiation position moves relative to the workpiece, and the control unit moves the laser irradiation position to a first side in the processing direction. A first line processing process for processing a first processing line among the multiple processing lines by a line processing process in which a laser irradiation position is moved to a second side opposite to the first side in the processing direction, and a second line processing process for processing a second processing line different from the first processing line among the multiple processing lines by a line processing process in which a laser irradiation position is moved to a second side opposite to the first side in the processing direction are sequentially executed, and during a switching period from the end of the first line processing process to the start of the second line processing process, the processing axis drive unit decelerates the laser irradiation position that has passed the first processing line to the first side in the processing direction toward the first side. a reversal drive is performed to move the laser irradiation position to the second processing line by rotating the laser beam in the feed direction, stopping the laser beam, and then accelerating toward the second side, and the feed axis drive unit moves the laser irradiation position in the feed direction from a first virtual straight line extending in the processing direction along the first processing line to the outside of the first processing line to a second virtual straight line extending in the processing direction along the second processing line to the outside of the second processing line, and in the processing direction, the imaging range is located on the second side of the laser irradiation position, and the imaging unit images a portion of the object to be processed that overlaps with the imaging range during the switching period.

[0007] A laser processing method according to a first aspect of the present invention is a laser processing method for processing a first processing line among multiple processing lines of a workpiece having multiple processing lines parallel to each other, and subsequently processing a second processing line different from the first processing line, the method including the steps of: supporting the workpiece with a support member so that the processing lines are parallel to a predetermined processing direction; performing a first line processing process in which a laser beam is irradiated from the processing head to the laser irradiation position in a state in which the laser irradiation position is aligned with the first processing line by a feed axis drive unit that drives at least one of the processing head and the support member, which irradiate the laser beam to the predetermined laser irradiation position, in a feed direction perpendicular to the processing direction, while moving the laser irradiation position to a first side in the processing direction relative to the workpiece by a processing axis drive unit that drives at least one of the processing head and the support member in the processing direction; and decelerating and stopping the laser irradiation position that has passed the first processing line toward the first side in the processing direction, thereby accelerating the laser irradiation position toward a second side opposite to the first side, so that the laser irradiation position reaches the second processing line. the feed axis drive unit to move the laser irradiation position in the feed direction from a first virtual straight line extending in the processing direction along the first processing line to an outside of the first processing line to a second virtual straight line extending in the processing direction along the second processing line to an outside of the second processing line, while performing a reversal drive to move the laser irradiation position in the feed direction by the feed axis drive unit; the image of the workpiece by an image capture unit that captures a predetermined image capture range that moves relatively to the workpiece integrally with the laser irradiation position as the laser irradiation position moves relative to the workpiece; and the feed axis drive unit to perform a second line processing process in which the laser irradiation position is moved to a second side in the processing direction relative to the workpiece while irradiating laser light from the processing head to the laser irradiation position with the laser irradiation position aligned with the second processing line by the feed axis drive unit, wherein in the processing direction, the image capture range is located on the second side of the laser irradiation position, and the image capture unit captures an image of a portion of the workpiece that overlaps with the image capture range during a switching period from the end of the first line processing to the start of the second line processing.

[0008] In the first aspect (laser processing device and laser processing method) of the present invention configured as above, a first line processing process for processing a first processing line and a second line processing process for processing a second processing line are performed using a processing axis drive unit that moves the laser irradiation position relative to the workpiece in the processing direction and a feed axis drive unit that moves the laser irradiation position relative to the workpiece in the feed direction. Specifically, the first line processing process is performed by irradiating the laser irradiation position with a laser beam while aligning the laser irradiation position with the first processing line by the feed axis drive unit and moving the laser irradiation position to the first side in the processing direction with respect to the workpiece by the processing axis drive unit. Next, the second line processing process is performed by irradiating the laser beam with the laser irradiation position with the feed axis drive unit and moving the laser irradiation position to the second side in the processing direction with respect to the workpiece by the processing axis drive unit. During the switching period between the first line processing and the second line processing, the processing axis drive unit and the feed axis drive unit perform the following operations to move the laser irradiation position that has passed the first processing line toward the second processing line. That is, the processing axis drive unit performs a reverse drive in the processing direction to cause the laser irradiation position that has passed the first processing line to the first side to decelerate and stop toward the first side, and then accelerate toward the second side, thereby causing the laser irradiation position to reach the second processing line. Also, the feed axis drive unit moves the laser irradiation position in the feed direction from a first virtual straight line that is extended in the processing direction along the first processing line to the outside of the first processing line to a second virtual straight line that is extended in the processing direction along the second processing line to the outside of the second processing line.

[0009] In addition, in the first aspect of the present invention, the workpiece is imaged by an imaging unit that images a predetermined imaging range that moves relative to the workpiece together with the laser irradiation position as the laser irradiation position moves relative to the workpiece. In particular, the imaging range is located on the second side of the laser irradiation position in the processing direction, and the imaging unit images a portion of the workpiece that overlaps with the imaging range during the switching period. In this way, the switching period is effectively used to image the workpiece. As a result, it is possible to suppress the effect of the switching period for switching the moving direction of the laser light on the time required to complete processing of the workpiece.

[0010] The laser processing device may be configured such that, during the switching period, the control unit causes the feed axis drive unit to stop the laser irradiation position at a timing that overlaps with the timing at which the processing axis drive unit stops the laser irradiation position by reverse drive, thereby providing a stop period during which the laser irradiation position stops in both the processing direction and the feed direction, and the imaging unit images a portion of the workpiece that overlaps with the imaging range during the stop period. With this configuration, a still image of the workpiece can be obtained by effectively utilizing the switching period.

[0011] The laser processing device may be configured so that, during the switching period, the feed axis driver finishes moving the laser irradiation position from the first virtual straight line to the second virtual straight line before the processing axis driver stops the laser irradiation position in the reverse drive. With this configuration, the switching period can be effectively used to obtain a still image of the workpiece.

[0012] The laser processing device may be configured such that, during the switching period, the feed axis driver starts moving the laser irradiation position from the first virtual straight line to the second virtual straight line after the processing axis driver stops the laser irradiation position in the reverse drive. With this configuration, the switching period can be effectively used to obtain a still image of the processing object.

[0013] The laser processing apparatus may be configured such that the feed axis driver moves the laser irradiation position from the first virtual straight line to the second virtual straight line so that the laser irradiation position passes through a temporary stop position different from both the first virtual straight line and the second virtual straight line in the feed direction, and the control unit controls the processing axis driver and the feed axis driver to provide a stop period such that the feed axis driver stops the laser irradiation position at the temporary stop position at the same time as the processing axis driver stops the laser irradiation position by the reverse drive. With such a configuration, the switching period can be effectively used to obtain a still image of the workpiece.

[0014] Various specific locations of the pause position are possible. That is, the pause position may be provided in the section between the first virtual straight line and the second virtual straight line in the feed direction. Alternatively, the pause position may be provided outside the section between the first virtual straight line and the second virtual straight line in the feed direction.

[0015] In addition, various imaging targets of the imaging unit are assumed. That is, the laser processing device may be configured so that the processing object has a plurality of subsequent processing lines that are perpendicular to the plurality of processing lines, and the imaging unit images the portion included in the imaging range where the processing lines and the subsequent processing lines intersect. Alternatively, the imaging unit may image an alignment mark provided on the processing object.

[0016] A laser processing apparatus according to a second aspect of the present invention includes a support member that supports a workpiece having a plurality of parallel processing lines so that the processing lines are parallel to a predetermined processing direction; a processing head that irradiates a laser beam to a predetermined laser irradiation position; a processing axis drive unit that moves the laser irradiation position relative to the workpiece in the processing direction by driving at least one of the support member and the processing head in the processing direction; a feed axis drive unit that moves the laser irradiation position relative to the workpiece in the feed direction by driving at least one of the support member and the processing head in a feed direction perpendicular to the processing direction; and a control unit that processes the processing lines by executing a line processing process in which the processing head irradiates the laser beam to the laser irradiation position in a state in which the laser irradiation position is aligned with the processing line by the feed axis drive unit, while moving the laser irradiation position in the processing direction relative to the workpiece by the processing axis drive unit, and the control unit performs a first line processing process to process a first processing line of the plurality of processing lines by a line processing process to move the laser irradiation position to a first side in the processing direction, and a second line processing process to move the laser irradiation position to a second side opposite to the first side in the processing direction. In a switching period from the end of the first line processing process to the start of the second line processing process, the processing axis drive unit performs a reversal drive in the processing direction to cause the laser irradiation position that has passed the first processing line to the first side to decelerate and stop toward the first side, and then accelerate toward the second side, thereby causing the laser irradiation position to arrive at the second processing line. The feed axis drive unit drives the first processing line. a continuous feed drive is executed to continuously move the laser irradiation position in the feed direction from a first virtual straight line extending in the processing direction along the line to the outside of the first processing line to a second virtual straight line extending in the processing direction along the second processing line to the outside of the second processing line, and the control unit controls the processing axis drive unit and the feed axis drive unit so that the feed axis drive unit starts the continuous feed drive before the processing axis drive unit stops the laser irradiation position by the reverse drive, and the feed axis drive unit ends the continuous feed drive after the processing axis drive unit stops the laser irradiation position by the reverse drive,The feed shaft drive unit moves the laser irradiation position in the feed direction before and after the movement of the laser irradiation position in the processing direction stops due to the reverse drive.

[0017] A laser processing method according to a second aspect of the present invention is a laser processing method for processing a first processing line among a plurality of processing lines of a workpiece having a plurality of processing lines parallel to each other, and subsequently processing a second processing line different from the first processing line, the method including the steps of: supporting the workpiece with a support member so that the processing lines are parallel to a predetermined processing direction; performing a first line processing process in which the laser irradiation position is aligned with the first processing line by a feed axis drive unit that drives at least one of the processing head and the support member, which irradiate the laser light to the predetermined laser irradiation position, and a processing axis drive unit that drives at least one of the processing head and the support member in the processing direction, while irradiating the laser light from the processing head to the laser irradiation position in a state where the laser irradiation position is aligned with the first processing line; and performing a reversal drive by the processing axis drive unit to move the laser irradiation position to a first side in the processing direction relative to the workpiece, the processing axis drive unit decelerating and stopping the laser irradiation position that has passed the first processing line toward the first side in the processing direction, and then accelerating toward a second side opposite to the first side, so that the laser irradiation position reaches the second processing line. a step of performing continuous feed drive for continuously moving a laser irradiation position in a feed direction by a feed axis drive unit from a first virtual straight line extending in the processing direction along the processing line to the outside of the first processing line to a second virtual straight line extending in the processing direction along the second processing line to the outside of the second processing line; and a second line processing for moving the laser irradiation position to a second side in the processing direction with respect to the workpiece by the processing axis drive unit while irradiating a laser beam from the processing head to the laser irradiation position in a state where the laser irradiation position is aligned with the second processing line by the feed axis drive unit. and a step of executing processing, wherein, during a switching period from the end of the first line processing process to the start of the second line processing process, the processing axis drive unit and the feed axis drive unit are controlled by a control unit so that the feed axis drive unit starts the continuous feed drive before the processing axis drive unit stops the laser irradiation position by the reversal drive, and the feed axis drive unit ends the continuous feed drive after the processing axis drive unit stops the laser irradiation position by the reversal drive, and the feed axis drive unit moves the laser irradiation position in the feed direction before and after the movement of the laser irradiation position in the processing direction stops due to the reversal drive.

[0018] In the second aspect (laser processing device and laser processing method) of the present invention configured as above, a first line processing process for processing a first processing line and a second line processing process for processing a second processing line are performed using a processing axis drive unit that moves the laser irradiation position relative to the workpiece in the processing direction and a feed axis drive unit that moves the laser irradiation position relative to the workpiece in the feed direction. Specifically, the first line processing process is performed by irradiating the laser beam to the laser irradiation position in a state where the laser irradiation position is aligned with the first processing line by the feed axis drive unit, while moving the laser irradiation position to the first side in the processing direction with respect to the workpiece by the processing axis drive unit. Next, the second line processing process is performed by irradiating the laser beam to the laser irradiation position in a state where the laser irradiation position is aligned with the second processing line by the feed axis drive unit, while moving the laser irradiation position to the second side in the processing direction with respect to the workpiece by the processing axis drive unit. During the switching period between the first line processing and the second line processing, the processing axis drive unit and the feed axis drive unit perform the following operations to move the laser irradiation position that has passed the first processing line toward the second processing line. That is, the processing axis drive unit performs a reverse drive in the processing direction to cause the laser irradiation position that has passed the first processing line to the first side to decelerate and stop toward the first side, and then accelerate toward the second side, thereby causing the laser irradiation position to reach the second processing line. Also, the feed axis drive unit moves the laser irradiation position in the feed direction from a first virtual straight line that is extended in the processing direction along the first processing line to the outside of the first processing line to a second virtual straight line that is extended in the processing direction along the second processing line to the outside of the second processing line.

[0019] In particular, in the second aspect of the present invention, the feed axis drive unit executes a continuous feed drive that continuously moves the laser irradiation position in the feed direction from the first virtual straight line to the second virtual straight line. The control unit controls the machining axis drive unit and the feed axis drive unit so that the feed axis drive unit starts the continuous feed drive before the machining axis drive unit stops the laser irradiation position by the reverse drive, and ends the continuous feed drive after the machining axis drive unit stops the laser irradiation position by the reverse drive, and causes the feed axis drive unit to move the laser irradiation position in the feed direction before and after the movement of the laser irradiation position in the machining direction stops due to the reverse drive. In other words, during the switching period, both the period in which the laser irradiation position is decelerated to the first side of the machining direction and the period in which the laser irradiation position is accelerated to the second side of the machining direction are effectively used for moving the laser irradiation position in the feed direction. As a result, it is possible to suppress the effect of the switching period in which the moving direction of the laser light is switched on the time required to complete processing of the workpiece.

[0020] A laser processing program according to the present invention causes a computer to execute the above-described laser processing method.

[0021] A recording medium according to the present invention records the above-mentioned laser processing program in a computer-readable manner.

[0022] The semiconductor chip manufacturing method of the present invention includes a step of processing a semiconductor substrate on which a plurality of semiconductor chips are arranged and separated by a processing line, by the above-mentioned laser processing method, and a step of separating each of the plurality of semiconductor chips by expanding a tape that holds the semiconductor substrate processed by the laser processing method by its adhesive force.

[0023] The semiconductor chip of the present invention is manufactured by a step of processing a semiconductor substrate on which a plurality of semiconductor chips separated by processing lines are arranged, using the above-mentioned laser processing method, and a step of separating each of the plurality of semiconductor chips by expanding a tape that holds the semiconductor substrate processed by the laser processing method by its adhesive force. Effect of the Invention

[0024] According to the present invention, in a laser processing technique in which the moving direction of a laser beam is switched between the forward and return sides to process a processing line of a workpiece, it is possible to reduce the effect that the switching period for switching the moving direction of the laser beam has on the time required to complete processing of the workpiece. [Brief description of the drawings]

[0025] [Figure 1] FIG. 1 is a front view showing a schematic diagram of an example of a laser processing apparatus according to the present invention. [Diagram 2] FIG. 2 is a plan view showing a schematic diagram of the laser processing apparatus shown in FIG. [Diagram 3] 2 is a block diagram showing an electrical configuration of the laser processing apparatus of FIG. 1. [Figure 4] 1 is a flow chart illustrating an example of a method for producing a laser-processed substrate after laser processing has been performed. [Diagram 5] 11 is a flowchart showing an example of removing a ring frame. [Figure 6] 11 is a flowchart showing an example of transferring a ring frame. [Figure 7A] FIG. 7 is a plan view showing a schematic example of an operation executed according to the flowcharts of FIGS. 5 and 6. [Figure 7B] FIG. 7 is a plan view showing a schematic example of an operation executed according to the flowcharts of FIGS. 5 and 6. [Figure 7C] FIG. 7 is a plan view showing a schematic example of an operation executed according to the flowcharts of FIGS. 5 and 6. [Figure 7D] FIG. 7 is a plan view showing a schematic example of an operation executed according to the flowcharts of FIGS. 5 and 6. [Figure 7E] FIG. 7 is a plan view showing a schematic example of an operation executed according to the flowcharts of FIGS. 5 and 6. [Figure 8] 10 is a flowchart showing an example of storing a ring frame. [Figure 9] 1 is a flowchart illustrating an example of ring frame alignment; [Figure 10] FIG. 11 is a plan view illustrating an example of an operation performed in ring frame alignment. [Figure 11] 4 is a flowchart showing an example of substrate processing. [Figure 12] 12 is a plan view showing an example of an operation executed according to the flowchart of FIG. 11. [Figure 13A] 11 is a flowchart showing an example of calibration. [Figure 13B] 13B is a flowchart showing an example of stage plane determination performed in the calibration of FIG. 13A. [Figure 13C] 13B is a flowchart showing an example of substrate plane determination performed in the calibration of FIG. 13A. [Figure 14] 11 is a flowchart showing basic steps of a line processing process for each division line. [Figure 15A] 15 is a diagram showing a schematic diagram of a first example of the operation executed according to the flowchart of FIG. 14. [Figure 15B] 15 is a diagram illustrating a second example of the operation executed according to the flowchart of FIG. 14. [Figure 15C] FIG. 15 is a diagram illustrating a third example of the operation executed according to the flowchart of FIG. [Figure 15D] FIG. 15 is a diagram illustrating a fourth example of the operation executed according to the flowchart of FIG. [Figure 15E] FIG. 15 is a diagram illustrating a fifth example of the operation executed according to the flowchart of FIG. [Figure 15F] FIG. 15 is a diagram illustrating a sixth example of the operation executed according to the flowchart of FIG. [Figure 15G] FIG. 15 is a diagram illustrating a seventh example of the operation executed according to the flowchart of FIG. [Figure 16] 13 is a flowchart showing a first application example of line processing processing applied to each division line. [Figure 17] FIG. 17 is a diagram illustrating an example of an operation executed according to the flowchart of FIG. 16. [Figure 18] 13 is a flowchart showing a second application example of the line processing process applied to each division line. [Figure 19A] FIG. 20 is a diagram illustrating a first example of the operation executed according to the flowchart of FIG. 18. [Figure 19B] FIG. 20 is a diagram illustrating a second example of the operation executed according to the flowchart of FIG. 18. [Figure 20] 18. FIG. 21 is a diagram showing an example of an image of a semiconductor substrate acquired in step S1008 in FIG. 16 or step S1104 in FIG. [Figure 21] 11 is a flowchart showing an example of a method for determining laser processing conditions in a line processing process. [Figure 22A] FIG. 13 is a diagram showing parameters related to determining laser processing conditions. [Figure 22B] FIG. 13 is a diagram showing the effect of laser processing conditions over time. [Figure 22C] FIG. 22 is a diagram showing an example of a table to be referred to in determining the laser processing conditions in FIG. 21. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0026] Fig. 1 is a front view showing an example of a laser processing apparatus according to the present invention, and Fig. 2 is a plan view showing the laser processing apparatus of Fig. 1. In both figures and the following figures, the X direction, which is a horizontal direction, the Y direction, which is a horizontal direction perpendicular to the X direction, and the Z direction, which is a vertical direction, are shown as appropriate. Furthermore, the (+X) side of the X direction (the right side of the paper in Fig. 2) and the (-X) side opposite to the (+X) side of the X direction (the left side of the paper in Fig. 2) are shown as appropriate, and the (+Y) side of the Y direction (the upper side of the paper in Fig. 2) and the (-Y) side opposite to the (+Y) side of the Y direction (the lower side of the paper in Fig. 2) are shown as appropriate.

[0027] The laser processing device 1 processes the semiconductor substrate W (object to be processed) by irradiating the semiconductor substrate W with laser light. The semiconductor substrate W is held by a ring frame Fr via a tape E. The tape E is a dicing tape or a bonding tape, and the surface (upper surface) of the tape E is adhesive. The ring frame Fr has an outer shape in which a part of a regular octagon is cut out to provide a slit Fs, and a circular opening Fo is provided in the center of the ring frame Fr. The surface of the tape E faces the ring frame Fr from below so as to overlap the entire opening Fo, and the periphery of the surface of the tape E is attached to the bottom surface of the ring frame Fr by adhesive force. In addition, the semiconductor substrate W is attached to the surface of the tape E by adhesive force. In this way, the semiconductor substrate W is transported in the laser processing device 1 while being held by the ring frame Fr via the tape E. The semiconductor substrate W has a surface and a back surface opposite to the surface, and an electronic circuit is formed on the surface of the semiconductor substrate W, while the back surface of the semiconductor substrate W is flat. The front surface of the semiconductor substrate W faces downward and is attached to the front surface of the tape E. That is, the semiconductor substrate W is held in a state in which the back surface of the semiconductor substrate W faces upward.

[0028] The laser processing apparatus 1 includes a substrate accommodating section 2 that accommodates a semiconductor substrate W, and a chuck stage 3 (support member) that holds the semiconductor substrate W removed from the substrate accommodating section 2. The laser processing apparatus 1 includes a flat base plate 11, and the substrate accommodating section 2 and the chuck stage 3 are supported by the base plate 11. The chuck stage 3 is disposed on the (+X) side of the substrate accommodating section 2 in the X direction, and the chuck stage 3 is disposed on the (-Y) side of the substrate accommodating section 2 in the Y direction. The space on the (-X) side of the chuck stage 3 in the X direction and on the (-Y) side of the substrate accommodating section 2 in the Y direction becomes a substrate passing area Aw.

[0029] The substrate accommodating section 2 has a substrate accommodating cassette 21. The substrate accommodating cassette 21 has a pair of side walls 22 provided on both sides in the X direction and an opening 23 provided between the side walls 22, and the opening 23 faces the (-Y) side (i.e., the substrate transfer area Aw side). The pair of side walls 22 are flat plates provided perpendicular to the X direction and face each other in the X direction. In addition, a support protrusion 24 is provided on the inner side of each of the pair of side walls 22. Thus, the pair of support protrusions 24 facing each other in the X direction are provided at the same height. Then, a ring frame Fr that holds a semiconductor substrate W can be inserted into the upper side of the pair of support protrusions 24 from the (-Y) side through the opening 23. Both ends in the X direction of the ring frame Fr thus inserted are supported from below by the pair of support protrusions 24. That is, the upper sides of the pair of support protrusions 24 function as slots 25 that accommodate the ring frame Fr, and the ring frame Fr inserted into the slot 25 from the (-Y) side through the opening 23 is supported by the pair of support protrusions 24 that correspond to the slot 25. Therefore, by inserting the ring frame Fr into the slot 25 of the substrate accommodating cassette 21, the semiconductor substrate W supported by the ring frame Fr can be accommodated in the substrate accommodating cassette 21, and by pulling out the ring frame Fr from the slot 25 of the substrate accommodating cassette 21, the semiconductor substrate W can be removed from the substrate accommodating cassette 21.

[0030] Further, the substrate accommodating unit 2 has a Z-axis slider 26 that supports the substrate accommodating cassette 21, and a Z-axis drive mechanism 27 that drives the Z-axis slider 26 in the Z direction. The Z-axis drive mechanism 27 is a single-axis robot attached to the base plate 11, and has a Z-axis drive transmission unit 271 that supports the Z-axis slider 26 movably in the Z direction, and a Z-axis cassette motor 272 that drives the Z-axis slider 26 supported by the Z-axis drive transmission unit 271 in the Z direction. The Z-axis drive transmission 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 of the ball screw. However, the specific configuration of the Z-axis drive mechanism 27 is not limited to this example, and may be, for example, a linear motor. The Z-axis drive mechanism 27 drives the Z-axis slider 26 supported by the Z-axis drive transmission part 271 by the Z-axis cassette motor 272, thereby moving the substrate accommodation cassette 21 supported by the Z-axis slider 26 in the Z direction.

[0031] A substrate insertion height 211 is provided for the substrate accommodating cassette 21, and the semiconductor substrate W can be inserted into and withdrawn from the slot 25 located at the substrate insertion height 211. Therefore, by moving the substrate accommodating cassette 21 in the Z direction using the Z-axis drive mechanism 27 to change the slot 25 located at the substrate insertion height 211 among the multiple slots 25, the slot 25 into which the semiconductor substrate W is inserted and withdrawn can be changed.

[0032] In contrast, the laser processing apparatus 1 includes a Y-axis transport mechanism 4 that transports the ring frame Fr in the Y direction between the slot 25 at the substrate insertion height 211 and the substrate transfer area Aw. The Y-axis transport mechanism 4 includes a lift hand 41, a Y-axis slider 43 that supports the lift hand 41, and a Y-axis drive mechanism 45 that drives the Y-axis slider 43 in the Y direction. The Y-axis drive mechanism 45 is a single-axis robot attached to the base plate 11 by a frame as shown in the attached drawings, and includes a Y-axis drive transmission unit 451 that supports the Y-axis slider 43 movably in the Y direction, and a Y-axis lift hand motor 452 that drives the Y-axis slider 43 supported by the Y-axis drive transmission unit 451 in the Y direction. The Y-axis drive transmission unit 451 has a ball screw driven by the Y-axis lift hand motor 452, and the Y-axis slider 43 is attached to the nut of the ball screw. However, the specific configuration of the Y-axis drive mechanism 45 is not limited to this example, and may be, for example, a linear motor. The Y-axis drive mechanism 45 drives the Y-axis slider 43 supported by the Y-axis drive transmission part 451 with the Y-axis lift hand motor 452, thereby moving the lift hand 41 supported by the Y-axis slider 43 in the Y direction.

[0033] The lift hand 41 has a base part 411 supported by the Y-axis slider 43, and a fork 412 protruding from the base part 411 to the (+Y) side. The fork 412 is located at the substrate insertion height 211 and can hold the ring frame Fr from below. As will be described later, the Y-axis transport mechanism 4 drives the lift hand 41 in the Y direction using the Y-axis drive mechanism 45, thereby moving the ring frame Fr held by the fork 412 of the lift hand 41 between the substrate accommodation cassette 21 and the substrate transfer area Aw.

[0034] The laser processing apparatus 1 also includes an XZ-axis transport mechanism 5 that transports the ring frame Fr in the X direction between the lift hand 41 located in the substrate transfer area Aw and the chuck stage 3. The XZ-axis transport mechanism 5 includes a suction hand 51, an X-axis slider 53 that supports the suction hand 51, and an X-axis drive unit 55 that drives the X-axis slider 53 in the X direction. The X-axis drive unit 55 is a single-axis robot attached to the base plate 11 by a frame shown in the attached drawings, and includes an X-axis drive transmission unit 551 that supports the X-axis slider 53 movably in the X direction, and an X-axis suction hand motor 552 that drives the X-axis slider 53 supported by the X-axis drive transmission unit 551 in the X direction. The X-axis drive transmission unit 551 has a ball screw driven by the X-axis suction hand motor 552, and the X-axis slider 53 is attached to the nut of the ball screw. However, the specific configuration of the X-axis drive unit 55 is not limited to this example, and may be, for example, a linear motor. The X-axis drive unit 55 drives the X-axis slider 53 supported by the X-axis drive transmission unit 551 using the X-axis suction hand motor 552, thereby moving the suction hand 51 supported by the X-axis slider 53 in the X direction.

[0035] The XZ-axis transport mechanism 5 also includes a Z-axis slider 56 attached to the suction hand 51 and a Z-axis drive unit 58 that drives the Z-axis slider 56 in the Z direction relative to the X-axis slider 53. That is, the suction hand 51 is supported by the X-axis slider 53 via the Z-axis slider 56 and the Z-axis drive unit 58. The Z-axis drive unit 58 is a single-axis robot attached to the X-axis slider 53, and includes a Z-axis drive transmission unit 581 that supports the Z-axis slider 56 movably in the Z direction, and a Z-axis suction hand motor 582 that drives the Z-axis slider 56 supported by the Z-axis drive transmission unit 581 in the Z direction. The Z-axis drive transmission unit 581 has a ball screw driven by the Z-axis suction hand motor 582, and the Z-axis slider 56 is attached to the nut of the ball screw. However, the specific configuration of the Z-axis drive unit 58 is not limited to this example, and may be, for example, a linear motor. The Z-axis slider 56 extends from the Z-axis drive unit 58 to the lower side of the X-axis drive transmission unit 551, and the suction hand 51 is attached to the lower end of the Z-axis slider 56. The Z-axis drive unit 58 drives the Z-axis slider 56 supported by the Z-axis drive transmission unit 581 using a Z-axis suction hand motor 582, thereby moving the suction hand 51 supported by the Z-axis slider 56 in the Z direction.

[0036] The suction hand 51 has a base portion 511 supported by the Z-axis slider 56 and an annular suction member 512 protruding from the base portion 511 to the (+Y) side. The annular suction member 512 has an annular shape, and a plurality of suction holes are opened in a bottom surface 513 of the annular suction member 512. The ring frame Fr can be held from above by the suction hand 51 by sucking the ring frame Fr with negative pressure generated in each suction hole of the bottom surface 513 while the bottom surface 513 of the annular suction member 512 abuts against the ring frame Fr from above. As described later, the XZ-axis transport mechanism 5 drives the suction hand 51 in the X direction by the X-axis drive unit 55 and drives the suction hand 51 in the Z direction by the Z-axis drive unit 58, thereby moving the ring frame Fr held by the annular suction member 512 of the suction hand 51 between the substrate transfer area Aw and the chuck stage 3.

[0037] The chuck stage 3 has a suction plate 31 on which a ring frame Fr that supports the semiconductor substrate W via a tape E is placed. The suction plate 31 has a circular shape, and a plurality of suction holes are opened on an upper surface 311 of the suction plate 31. The tape E that contacts the upper surface 311 of the suction plate 31 is sucked by a negative pressure generated in each suction hole of the upper surface 311 of the suction plate 31, so that the tape E can be fixed to the suction plate 31. Furthermore, the chuck stage 3 has a plurality of clampers 32 provided on the periphery of the suction plate 31. The chuck stage 3 fixes the ring frame Fr to the suction plate 31 by making the clamper 32 face the ring frame Fr placed on the suction plate 31 from above and sandwiching the ring frame Fr between the clamper 32 and the suction plate 31. Moreover, the chuck stage 3 releases the ring frame Fr from being fixed to the suction plate 31 by retracting the clamper 32 to the side from the ring frame Fr.

[0038] In this manner, the chuck stage 3 holds the semiconductor substrate W supported on the ring frame Fr via the tape E by suction of the tape E by the suction plate 31 and fixing of the ring frame Fr by the clamper 32. By using the clamper 32 in this manner, the tape E can be sucked to the suction plate 31 with a weaker suction force than when the semiconductor substrate W is held only by suction of the tape E by the suction plate 31, and the effect of suction of the tape E on the semiconductor substrate W can be mitigated.

[0039] The laser processing apparatus 1 also includes an XYθ driving table 6 that supports the chuck stage 3. The XYθ driving table 6 is disposed on the base plate 11 and drives the chuck stage 3 in the X, Y and θ directions relative to the base plate 11. Here, the θ direction is a rotation direction centered on a rotation axis parallel to the Z direction. That is, the XYθ driving table 6 has a Y-axis guide 61 attached to the base plate 11 parallel to the Y direction, a Y-axis slider 62 supported by the Y-axis guide 61 so as to be movable in the Y direction, and a Y-axis driving unit 63 that drives the Y-axis slider 62 in the Y direction. The Y-axis driving unit 63 is a single-axis robot attached to the base plate 11, and has a Y-axis drive transmission unit 631 that supports the Y-axis slider 62 so as to be movable in the Y direction, and a Y-axis table motor 632 that drives the Y-axis slider 62 supported by the Y-axis drive transmission unit 631 in the Y direction. The Y-axis drive transmission unit 631 has a ball screw driven by a Y-axis table motor 632, and the Y-axis slider 62 is attached to the nut of the ball screw. However, the specific configuration of the Y-axis drive unit 63 is not limited to this example, and may be, for example, a linear motor.

[0040] Further, the XYθ drive table 6 has an X-axis slider 64 and an X-axis drive unit 65 that drives the X-axis slider 64 in the X direction relative to the Y-axis slider 62. The X-axis drive unit 65 is a single-axis robot attached to the Y-axis slider 62, and has an X-axis drive transmission unit 651 that supports the X-axis slider 64 movably in the X direction, and an X-axis table motor 652 that drives the X-axis slider 64 supported by the X-axis drive transmission unit 651 in the X direction. The X-axis drive transmission 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 of the ball screw. However, the specific configuration of the X-axis drive unit 65 is not limited to this example, and may be, for example, a linear motor.

[0041] Furthermore, the XYθ drive table 6 has a θ-axis table motor 66 attached to the X-axis slider 64. This θ-axis table motor 66 drives the chuck stage 3 relative to the X-axis slider 64 in the θ direction.

[0042] Such an XYθ drive table 6 can drive the chuck stage 3 in the Y direction by the Y-axis table motor 632, drive the chuck stage 3 in the X direction by the X-axis table motor 652, and drive the chuck stage 3 in the θ direction by the θ-axis table motor 66.

[0043] The laser processing device 1 also includes a laser processing unit 7 that performs laser processing on the semiconductor substrate W held on the chuck stage 3. The laser processing unit 7 has a processing head 71 that faces the semiconductor substrate W held on the chuck stage 3 from above. The processing head 71 has a laser light source 72 that generates laser light B of a predetermined frequency, and an optical system 73 (lens, diaphragm, etc.) that irradiates the semiconductor substrate W with the laser light B emitted from the laser light source 72. The 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 collects the laser light B emitted from the laser light source 72 at the laser irradiation position Lb using the optical system 73, thereby forming a modified layer in a portion of the semiconductor substrate W that overlaps with the laser irradiation position Lb.

[0044] The laser processing unit 7 also has a Z-axis slider 78 that supports the processing head 71, and a Z-axis drive unit 79 that drives the Z-axis slider 78 in the Z direction. The Z-axis drive unit 79 is a single-axis robot attached to a base plate, and has a Z-axis drive transmission unit 791 that supports the Z-axis slider 78 movably in the Z direction, and a Z-axis head motor 792 that drives the Z-axis slider 78 supported by the Z-axis drive transmission unit 791 in the Z direction. The Z-axis drive transmission 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 of the ball screw. However, the specific configuration of the Z-axis drive unit 79 is not limited to this example, and may be, for example, a linear motor. The Z-axis drive unit 79 drives the Z-axis slider 78 supported by the Z-axis drive transmission unit 791 using the Z-axis head motor 792, thereby moving the processing head 71 supported by the Z-axis slider 78 in the Z direction and moving the laser irradiation position Lb of the infrared camera 81 in the Z direction.

[0045] The laser processing device 1 also includes an imaging section 8 that images the semiconductor substrate W held by the chuck stage 3. In particular, two imaging sections 8 are provided, arranged to sandwich the laser processing section 7 in the X direction. When distinguishing between these two imaging sections 8, the imaging section 8 on the (+X) side of the laser processing section 7 is referred to as imaging section 8A, and the imaging section 8 on the (-X) side of the laser processing section 7 is referred to as imaging section 8B. In this manner, the imaging section 8A, the laser processing section 7, and the imaging section 8B are arranged in the X direction. The imaging sections 8A and 8B have the same basic configuration. Therefore, the configuration common to the imaging sections 8A and 8B will be described without distinguishing between them.

[0046] The imaging unit 8 has an infrared camera 81 that faces from above the semiconductor substrate W held by the chuck stage 3. The infrared camera 81 has a predetermined imaging range Ri (in other words, a field of view) and faces the imaging range Ri from above in the Z direction. The infrared camera 81 detects infrared rays emitted from the imaging range Ri to capture an image of the imaging range Ri.

[0047] Moreover, the imaging unit 8 has a Z-axis slider 88 that supports the infrared camera 81, and a Z-axis drive unit 89 that drives the Z-axis slider 88 in the Z direction. The Z-axis drive unit 89 is a single-axis robot attached to a base plate, and has a Z-axis drive transmission unit 891 that supports the Z-axis slider 88 movably in the Z direction, and a Z-axis camera motor 892 that drives the Z-axis slider 88 supported by the Z-axis drive transmission unit 891 in the Z direction. The Z-axis drive transmission 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 of the ball screw. However, the specific configuration of the Z-axis drive unit 89 is not limited to this example, and may be, for example, a linear motor. The Z-axis drive unit 89 drives the Z-axis slider 88 supported by the Z-axis drive transmission unit 891 using the Z-axis camera motor 892, thereby moving the infrared camera 81 supported by the Z-axis slider 88 in the Z direction and moving the imaging range Ri of the infrared camera 81 in the Z direction.

[0048] The infrared camera 81 of the imaging unit 8A and the infrared camera 81 of the imaging unit 8B have different resolutions. Specifically, the infrared camera 81 of the imaging unit 8A has a higher resolution than the infrared camera 81 of the imaging unit 8B, in other words, it has a narrower field of view. However, the resolution of the infrared camera 81 of the imaging unit 8A and the imaging unit 8B does not need to be different, and these infrared cameras 81 may have the same resolution. Also, in this example, the centers of the imaging range Ri of the imaging unit 8A, the laser irradiation position Lb of the processing head 71, and the imaging range Ri of the imaging unit 8B are aligned parallel to the X direction. However, these do not necessarily need to be parallel to the X direction, and it is sufficient that the imaging range Ri of the imaging unit 8A is located on the (+X) side and the imaging range Ri of the imaging unit 8B is located on the (-X) side with respect to the laser irradiation position Lb of the processing head 71.

[0049] Fig. 3 is a block diagram showing an electrical configuration of the laser processing apparatus of Fig. 1. As shown in Fig. 3, the laser processing apparatus 1 includes a control unit 100 that controls the configuration shown in Fig. 1 and Fig. 2. The control unit 100 includes a handling control calculation unit 110 in charge of controlling a substrate transport system (substrate accommodation unit 2, Y-axis transport mechanism 4, and XZ-axis transport mechanism 5) involved in transporting the semiconductor substrate W within the laser processing apparatus 1, and a laser processing control calculation unit 120 in charge of controlling a laser processing system (chuck stage 3, XYθ drive table 6, laser processing unit 7, and imaging unit 8) involved in laser processing of the semiconductor substrate W.

[0050] The control unit 100 also has a cassette control unit 111 that controls the insertion and removal operation of the semiconductor substrate W into and from the substrate accommodating cassette 21 in response to a command from the handling control calculation unit 110. The cassette control unit 111 adjusts the position of the substrate accommodating cassette 21 in the Z direction by controlling the Z-axis cassette motor 272, and adjusts the position of the lift hand 41 in the Y direction by controlling the Y-axis lift hand motor 452.

[0051] Furthermore, the control unit 100 has a hand control unit 112 that controls the transport operation of the semiconductor substrate W by the suction hand 51 in response to a command from the handling control calculation unit 110. The hand control unit 112 adjusts the position of the suction hand 51 in the X direction by controlling the X-axis suction hand motor 552, and the hand control unit 112 adjusts the position of the suction hand 51 in the Z direction by controlling the Z-axis suction hand motor 582. Furthermore, the hand control unit 112 controls a suction pump 591 that sucks the suction holes opening in the bottom surface 513 of the annular suction member 512 of the suction hand 51. That is, the hand control unit 112 causes the suction hand 51 to suck the ring frame Fr by supplying negative pressure to the suction holes by the suction pump 591, and causes the ring frame Fr to be separated from the suction hand 51 by stopping the supply of negative pressure to the suction holes by the suction pump 591.

[0052] The control unit 100 also has a stage control unit 121 that controls the substrate fixing operation by the chuck stage 3 and the driving of the chuck stage 3 in response to a command from the laser processing control calculation unit 120. The stage control unit 121 adjusts the position of the chuck stage 3 in the X-direction, the Y-direction, and the θ-direction by controlling the X-axis table motor 652, the Y-axis table motor 632, and the θ-axis table motor 66, respectively. Furthermore, the stage control unit 121 controls a clamper driving unit 691 that drives the clamper 32, thereby executing the fixing of the ring frame Fr to the suction plate 31 by the clamper driving unit 691 and the release of the fixing. Furthermore, the stage control unit 121 controls a suction pump 692 that sucks the suction holes opened in the upper surface 311 of the suction plate 31. That is, the stage control unit 121 causes the suction plate 31 to suction the tape E by supplying negative pressure to the suction holes by the suction pump 692, and releases the suction of the tape E by the suction plate 31 by stopping the supply of negative pressure to the suction holes by the suction pump 692.

[0053] The control unit 100 also has a camera control unit 122A that controls the imaging unit 8A, and a camera control unit 122B that controls the imaging unit 8B. These hand control units 112A, 112B execute the following control over the infrared camera 81 and Z-axis camera motor 892 of the imaging units 8A, 8B that are their respective targets. That is, each of the camera control units 122A, 122B causes the infrared camera 81 to capture an image of the semiconductor substrate W to obtain an image of the semiconductor substrate W, and adjusts the distance from the infrared camera 81 to the semiconductor substrate W in the Z direction by driving the infrared camera 81 in the Z direction with the Z-axis camera motor 892.

[0054] Furthermore, the control unit 100 has a processing head control unit 123 that controls the laser processing unit 7. The processing head control unit 123 drives the laser light source 72 to emit the laser light B from the laser light source 72, and drives the processing head 71 in the Z direction by the Z-axis head motor 792, thereby adjusting the distance from the processing head 71 to the semiconductor substrate W in the Z direction. Furthermore, the processing head 71 has a height detection unit 74 that detects the height (distance in the Z direction) from the semiconductor substrate W. This height detection unit 74 is a so-called distance sensor. Furthermore, the optical system 73 of the processing head 71 has a focus adjustment mechanism 75. The focus adjustment mechanism 75 adjusts the position at which the laser light B is focused by displacing the focus of the optical system 73 in the Z direction. In particular, the processing head control unit 123 controls the focus adjustment mechanism 75 based on the height from the semiconductor substrate W to the processing head 71 detected by the height detection unit 74, thereby focusing the laser light B at a predetermined position inside the semiconductor substrate W.

[0055] Each function of the control unit 100 described above is implemented by a processor such as a CPU (Central Processing Unit) or an FPGA (Field Programmable Gauge). This can be achieved by using a programmable gate array, etc.

[0056] Furthermore, the control unit 100 has a storage unit 190 which is a storage device such as a hard disk drive (HDD) or a solid state drive (SDD). A laser processing program 191 that specifies the operation to be executed by the laser processing device 1 for laser processing of the semiconductor substrate W is stored in the storage unit 190. That is, the control unit 100 executes each control to be described later with reference to Figs. 4 to 22C by executing the laser processing program 191. The laser processing program 191 is provided by a recording medium 192 external to the laser processing device 1, and the control unit 100 (computer) reads out the laser processing program 191 recorded in the recording medium 192 and stores it in the storage unit 190. Examples of such a recording medium 192 include a USB (Universal Serial Bus) memory and a storage device of an external computer.

[0057] Fig. 4 is a flow chart showing an example of a method for producing a laser-processed substrate after laser processing. The flow chart in Fig. 4 is executed according to the control of the control unit 100 based on the laser processing program 191. In step S101, the lift hand 41 takes out the ring frame Fr from the substrate accommodation cassette 21 to the substrate transfer area Aw, and in step S102, the suction hand 51 in the substrate transfer area Aw transfers the ring frame Fr from the lift hand 41 to the chuck stage 3. As a result, the semiconductor substrate W held by the ring frame Fr is taken out from the substrate accommodation cassette 21 to the substrate transfer area Aw, and then transferred from the substrate transfer area Aw to the chuck stage 3. Specifically, in step S101, the removal of the ring frame in Fig. 5 is executed, and in step S102, the transfer of the ring frame in Fig. 6 is executed.

[0058] FIG. 5 is a flowchart showing an example of removing a ring frame, FIG. 6 is a flowchart showing an example of transferring a ring frame, and FIGS. 7A to 7E are plan views showing typically an example of an operation performed according to the flowcharts of FIGS. 5 and 6.

[0059] In step S201 of Fig. 5, the control unit 100 checks whether the lift hand 41 is empty, i.e., whether a ring frame Fr is not placed on the lift hand 41. Whether the lift hand 41 is empty can be checked, for example, based on the history of operations performed by the lift hand 41. If the lift hand 41 is not empty (if "NO" in step S201), the flow chart of Fig. 5 ends, whereas if the lift hand 41 is empty (if "YES" in step S201), the process proceeds to step S201.

[0060] In step S202, the control unit 100 checks whether at least a part of the lift hand 41 is located inside the substrate storage cassette 21, in other words, whether it is located inside the substrate storage cassette 21 (i.e., on the (+Y) side) of the opening 23 of the substrate storage cassette 21. The check whether a part of the lift hand 41 is located inside the substrate storage cassette 21 can be performed based on the position of the lift hand 41 indicated by the output of the encoder of the Y-axis lift hand motor 452 that drives the lift hand 41 in the Y direction, for example. If the lift hand 41 has retreated to the (-Y) side from the substrate storage cassette 21 (if "NO" in step S202), the process proceeds to step S204 without executing step S203, whereas if a part of the lift hand 41 is located inside the substrate storage cassette 21 (if "YES" in step S202), the process proceeds to step S203. In step S203, the control unit 100 drives the lift hand 41 to the (-Y) side using the Y-axis lift hand motor 452, thereby pulling the lift hand 41 out from the substrate accommodating cassette 21 to the (-Y) side and retracting it to the (-Y) side of the substrate accommodating cassette 21.

[0061] In step S204, the control unit 100 drives the substrate accommodation cassette 21 in the Z direction using the Z-axis cassette motor 272, thereby positioning the slot 25 accommodating the ring frame Fr to be removed at a position a predetermined height higher than the substrate insertion height 211. This predetermined height is shorter than the distance between adjacent slots 25 in the Z direction. As a result, the bottom surface of the ring frame Fr to be removed is adjusted to a position a predetermined height higher than the lift hand 41.

[0062] 7A, in step S205, the control unit 100 drives the lift hand 41 to the (+Y) side by the Y-axis lift hand motor 452, thereby inserting the lift hand 41 into the inside of the substrate accommodating cassette 21. As a result, the lift hand 41 faces the ring frame Fr to be removed from below with a gap therebetween.

[0063] In step S206, the control unit 100 lowers the substrate storage cassette 21 in the Z direction by the Z-axis cassette motor 272. As a result, the ring frame Fr to be removed is placed on the lift hand 41 and is raised relative to the slot 25 (i.e., the pair of support protrusions 24 that define the slot 25).

[0064] In step S207, the control unit 100 drives the lift hand 41 to the (-Y) side by the Y-axis lift hand motor 452, thereby drawing out the lift hand 41 to the substrate passing area Aw provided outside the substrate accommodation cassette 21. As a result, the ring frame Fr placed on the lift hand 41 is positioned in the substrate passing area Aw, as shown in FIG. 7B.

[0065] 6, the control unit 100 adjusts the position of the suction hand 51 in the X direction by the X-axis suction hand motor 552, so that the suction hand 51 faces the ring frame Fr supported by the lift hand 41 in the substrate transfer area Aw from above, as shown in FIG. 7C. At this time, the control unit 100 adjusts the height of the suction hand 51 by the Z-axis suction hand motor 582, so that the suction hand 51 is positioned higher than the ring frame Fr. Therefore, the suction hand 51 faces the ring frame Fr with a gap therebetween.

[0066] In step S302, the control unit 100 lowers the suction hand 51 facing the ring frame Fr by the Z-axis drive transmission unit 581, and brings the bottom surface 513 of the suction hand 51 into contact with the upper surface of the ring frame Fr. In step S303, the control unit 100 generates negative pressure in the suction holes provided in the bottom surface 513 of the suction hand 51 by the suction pump 591, and the suction hand 51 adsorbs the ring frame Fr by this negative pressure. 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 by the Z-axis suction hand motor 582. As a result, the suction hand 51 lifts the ring frame Fr from the lift hand 41.

[0067] 7D, the control unit 100 drives the suction hand 51 to the (+X) side using the X-axis suction hand motor 552, thereby causing the suction hand 51 to face the chuck stage 3, to which the ring frame Fr is to be transferred, from above. At this time, the control unit 100 adjusts the height of the suction hand 51 using the Z-axis suction hand motor 582, thereby adjusting the ring frame Fr held by the suction hand 51 to a position higher than the chuck stage 3. Therefore, the ring frame Fr held by the suction hand 51 faces the chuck stage 3 with a gap therebetween.

[0068] In step S306, the control unit 100 lowers the suction hand 51 using the Z-axis suction hand motor 582, thereby placing the ring frame Fr (and the tape E) held by the suction hand 51 on the suction plate 31 of the chuck stage 3. In step S307, the control unit 100 stops the suction pump 591, and releases the suction of the ring frame Fr by the suction hand 51.

[0069] In step S308, the control unit 100 checks whether the destination of the ring frame Fr is the chuck stage 3. For example, if the destination of the ring frame Fr is the lift hand 41 as in step S104 described below, the determination in step S308 is "NO," and the flow chart in Fig. 6 ends. In this case, the destination of the ring frame Fr is the chuck stage 3, so the determination in step S308 is "YES," and the process proceeds to step S309.

[0070] In step S309, the control unit 100 drives the clamper 32 by the clamper driving unit 691, so that the ring frame Fr placed on the suction plate 31 of the chuck stage 3 is sandwiched between the clamper 32 and the suction plate 31, and the ring frame Fr is clamped. In step S310, the control unit 100 generates negative pressure in the suction holes provided on the upper surface 311 of the suction plate 31 by the suction pump 692, and the suction plate 31 uses this negative pressure to suction the tape E attached to the ring frame Fr. In this way, the ring frame Fr is held by the chuck stage 3. In step S311, the control unit 100 raises the suction hand 51 by the Z-axis suction hand motor 582. As a result, the suction hand 51 is retracted upward from the ring frame Fr held by the chuck stage 3. In this way, as shown in FIG. 7E, the transfer of the ring frame Fr from the substrate accommodation cassette 21 to the chuck stage 3 is completed (steps S101 and S102 in FIG. 4).

[0071] 4, substrate processing is performed in which the semiconductor substrate W held by the chuck stage 3 is processed with the laser light B, and the laser light B is irradiated onto a plurality of planned dividing lines provided on the semiconductor substrate W. Details of this substrate processing will be described later.

[0072] When the substrate processing is completed, steps S104 and S105 are executed. In step S104, the suction hand 51 transfers the ring frame Fr from the chuck stage 3 to the lift hand 41 in the substrate transfer area Aw, and in step S105, the lift hand 41 stores the ring frame Fr from the substrate transfer area Aw into the substrate accommodation cassette 21. As a result, the semiconductor substrate W held by the ring frame Fr is transferred from the chuck stage 3 to the substrate transfer area Aw, and then stored from the substrate transfer area Aw into the substrate accommodation cassette 21. Specifically, in step S104, the transfer of the ring frame in FIG. 6 is executed, and in step S105, the storage of the ring frame in FIG. 8 is executed, and the operations reverse to those in FIG. 7A to FIG. 7E described above are executed. Here, FIG. 8 is a flowchart showing an example of the storage of the ring frame.

[0073] The operation of FIG. 6 executed in step S104 is the same as the above-mentioned operation of FIG. 6 executed in step S102, so here, differences from the above-mentioned operation will be mainly described, and common operations will be omitted as appropriate. In step S301 of FIG. 6, the control unit 100 adjusts the position of the suction hand 51 in the X direction by the X-axis suction hand motor 552, so that the suction hand 51 faces the ring frame Fr placed on the chuck stage 3 from above. Then, the control unit 100 lowers the suction hand 51 to the ring frame Fr (step S302), and causes the suction hand 51 to suction the ring frame Fr (step S303). Next, the control unit 100 raises the suction hand 51 (step S304). As a result, the suction hand 51 lifts the ring frame Fr from the chuck stage 3.

[0074] In step S305, the control unit 100 drives the suction hand 51 to the (-X) side by the X-axis suction hand motor 552. At this time, the lift hand 41 is waiting in the substrate transfer area Aw, so that the suction hand 51 faces the lift hand 41 in the substrate transfer area Aw, which is the transfer destination of the ring frame Fr, from above. Then, the control unit 100 lowers the suction hand 51 by the Z-axis suction hand motor 582, thereby placing the ring frame Fr held by the suction hand 51 on the lift hand 41 (step S306). Then, the control unit 100 stops the suction pump 591 to release the suction of the ring frame Fr by the suction hand 51 (step S307). In step S308, the control unit 100 checks whether the transfer destination of the ring frame Fr is the chuck stage 3 or not. In this case, since the destination of the ring frame Fr is the lift hand 41 and not the chuck stage 3, the determination in step S308 is "NO," and the flow chart of FIG. 6 ends.

[0075] In step 401 of FIG. 8, the control unit 100 checks whether the ring frame Fr is placed on the lift hand 41. The check of placing the ring frame Fr on the lift hand 41 can be performed, for example, based on the operation history of the suction hand 51 that performs the placing of the ring frame Fr. When the placement of the ring frame Fr on the lift hand 41 is confirmed ("YES" in step S401), the control unit 100 checks whether at least a part of the lift hand 41 is located inside the substrate storage cassette 21 (step S402) in the same manner as in step S202 described above. If the lift hand 41 is retreated from the substrate storage cassette 21 to the (-Y) side ("NO" in step S402), the process proceeds to step S404 without executing step S403, whereas if a part of the lift hand 41 is located inside the substrate storage cassette 21 ("YES" in step S402), the process proceeds to step S403. In step S403, the control unit 100 drives the lift hand 41 to the (-Y) side using the Y-axis lift hand motor 452, thereby pulling the lift hand 41 out from the substrate accommodating cassette 21 to the (-Y) side and retracting it to the (-Y) side of the substrate accommodating cassette 21.

[0076] In step S404, the control unit 100 drives the substrate storage cassette 21 in the Z direction using the Z-axis cassette motor 272, thereby positioning the slot 25 (in other words, the pair of support protrusions 24 defining the slot 25) in which the ring frame Fr is to be stored, at a position a predetermined height lower than the substrate insertion height 211. As a result, the slot 25 in which the ring frame Fr is to be stored is adjusted to a position a predetermined height lower than the bottom surface of the ring frame Fr supported by the lift hand 41.

[0077] In step S405, the control unit 100 drives the lift hand 41 to the (+Y) side by the Y-axis lift hand motor 452, thereby inserting the lift hand 41 into the inside of the substrate storage cassette 21. As a result, the pair of support protrusions 24 that define the slot 25 to be stored face the ring frame Fr supported by the lift hand 41 from below with a gap therebetween.

[0078] In step S406, the control unit 100 raises the substrate storage cassette 21 in the Z direction using the Z-axis cassette motor 272. As a result, the ring frame Fr is placed on the pair of support protrusions 24 that define the slot 25 to be stored, and is raised relative to the lift hand 41. In step S407, the control unit 100 drives the lift hand 41 to the (-Y) side using the Y-axis lift hand motor 452, thereby drawing the lift hand 41 outward from the substrate storage cassette 21.

[0079] When the ring frame Fr is taken out or stored in the substrate accommodation cassette 21, ring frame alignment can be appropriately performed to align the ring frame Fr with respect to the lift hand 41. Fig. 9 is a flow chart showing an example of ring frame alignment, and Fig. 10 is a plan view showing a schematic example of an operation performed in the ring frame alignment. The flow chart in Fig. 9 is executed under the control of the control unit 100.

[0080] 10, the suction hand 51 is seen through to show the members (such as the alignment protrusions 413) below the suction hand 51. That is, in this example, the lift hand 41 has a plurality of alignment protrusions 413 protruding upward from the base portion 411. These alignment protrusions 413 correspond to the slits Fs of the ring frame Fr. Ring frame alignment is performed using the alignment protrusions 413 and the slits Fs.

[0081] In this ring frame alignment, the suction hand 51 suctions the ring frame Fr on the lift hand 41 (step S501). Then, the suction hand 51 holding the ring frame Fr rises to separate the ring frame Fr upward from the lift hand 41 (step S502). At this time, the height at which the ring frame Fr is separated from the lift hand 41 is adjusted so that the ring frame Fr is positioned at a height between the lower end and the upper end of the alignment protrusion 413 in the Z direction.

[0082] In step S503, the XYθ floating mechanism 561 built in the Z-axis slider 56 is turned on. This XYθ floating mechanism 561 selectively takes a floating state in which the suction hand 51 is floatingly supported, and a locked state in which the suction hand 51 is fixedly supported. Here, the floating support means that the suction hand 51 is supported in a state in which the suction hand 51 is movable in the X direction, the Y direction, and the θ direction relative to the XYθ floating mechanism 561, and the fixed support means that the suction hand 51 is supported in a state in which the suction hand 51 is fixed to the XYθ floating mechanism 561. When the XYθ floating mechanism 561 is turned on in step S503, the XYθ floating mechanism 561 floats the suction hand 51, and the suction hand 51 is movable in the X direction, the Y direction, and the θ direction relative to the XYθ floating mechanism 561.

[0083] In step S504, the lift hand 41 moves in the Y direction to bring the alignment protrusions 413 of the lift hand 41 into contact with the periphery of the ring frame Fr held by the suction hand 51. At this time, the suction hand 51 moves relative to the XYθ floating mechanism 561 so that the alignment protrusions 413 follow the periphery of the ring frame Fr. As a result, as shown in the column of step S504 in FIG. 10, each alignment protrusion 413 of the lift hand 41 engages with each slit Fs of the ring frame Fr, and the ring frame Fr is positioned relative to the lift hand 41.

[0084] In step S505, the XYθ floating mechanism 561 is locked. As a result, the suction hand 51 is fixedly supported by the XYθ floating mechanism 561. Then, in step S506, the suction hand 51 releases the ring frame Fr, and the ring frame Fr is placed on the lift hand 41. In step S507, the XYθ floating mechanism 561 is turned off, and the suction hand 51 is supported by the Z-axis slider 56 while being fixed to the Z-axis slider 56. In this way, the ring frame Fr can be positioned relative to the lift hand 41 (ring frame alignment).

[0085] Next, the details of the substrate processing will be described. Fig. 11 is a flowchart showing an example of the substrate processing, and Fig. 12 is a plan view showing a schematic example of an operation executed according to the flowchart of Fig. 11. The flowchart of Fig. 11 is executed under the control of the control unit 100.

[0086] In step S601 of the substrate processing in FIG. 11, a calibration is performed to obtain a plane of the upper surface (rear surface) of the semiconductor substrate W to be processed. FIG. 13A is a flow chart showing an example of the calibration, FIG. 13B is a flow chart showing an example of the stage plane determination performed in the calibration in FIG. 13A, and FIG. 13C is a flow chart showing an example of the substrate plane determination performed in the calibration in FIG. 13A. In the calibration in FIG. 13A, an image of the suction plate 31 or the semiconductor substrate W is appropriately taken. In the description here, it is assumed that the image is taken by the imaging unit 8B. However, even if the image is taken by the imaging unit 8A, the following operation can be similarly performed.

[0087] In step S701 of the calibration in Fig. 13A, stage plane identification (Fig. 13B) is performed. As shown in Fig. 13B, in the stage plane identification, a count value I for identifying a plurality of (three) imaging points Ps(I) provided on the upper surface 311 of the suction plate 31 of the chuck stage 3 is reset to zero (step S801), and the count value I is incremented by 1 (step S802). The imaging points Ps(I) are, for example, marks having a predetermined pattern.

[0088] In step S803, the control unit 100 adjusts the position of the chuck stage 3 using the XYθ drive table 6, thereby causing the imaging point Ps(I) to face the infrared camera 81 from below. This brings the imaging point Ps(I) into the field of view of the infrared camera 81. In step S803, the infrared camera 81 captures an image of the imaging point Ps(I) and obtains an image showing the imaging point Ps(I). In step S804, the control unit 100 checks whether a predetermined pattern of the imaging point Ps(I) can be detected from the image by image processing such as pattern matching.

[0089] If the focus of infrared camera 81 is shifted from imaging point Ps(I) and the predetermined pattern cannot be detected from the image ("NO" in step S804), control unit 100 drives infrared camera 81 in the Z direction using Z-axis camera motor 892 to change the distance of infrared camera 81 in the Z direction from imaging point Ps(I) (step S805). This changes the focus of infrared camera 81 in the Z direction. Steps S803 to S805 are repeated until infrared camera 81 focuses on imaging point Ps(I) and the predetermined pattern is detected ("YES" in step S804).

[0090] In step S806, the control unit 100 calculates the position (X, Y, Z) of the imaging point Ps(I) based on the predetermined pattern detected from the image acquired by imaging the imaging point Ps(I). The X and Y coordinates of the imaging point Ps(I) are calculated based on the position of the predetermined pattern included in the image. The Z coordinate of the imaging point Ps(I) is calculated based on the position in the Z direction of the infrared camera 81 when the image in which the predetermined pattern was detected was captured.

[0091] In step S807, it is confirmed whether the count value I has reached 2, i.e., whether the positions (X, Y, Z) of the two imaging points Ps(1) and Ps(2) have been acquired. If the count value I is less than 2 ("NO" in step S807), the process returns to step S802, and steps S802 to S806 are executed. If the count value I is 2 ("YES" in step S807), the process proceeds to step S808.

[0092] In step S808, a rotation angle θa is calculated for rotating the chuck stage 3 in the θ direction so that the straight line passing through the two imaging points Ps(1) and Ps(2) becomes horizontal. If the difference between the current rotation angle of the suction plate 31 (the actual rotation angle and the rotation angle θa) is not zero ("NO" in step S809), the chuck stage 3 is rotated by the rotation angle θa (step S810), and the process returns to step S801. In this manner, steps S801 to S809 are executed.

[0093] If the difference between the current rotation angle of the suction plate 31 (the actual 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 captures an image of the imaging point Ps(3) using the infrared camera 81 in the same manner as in step S803, and obtains an image showing the imaging point Ps(3). Then, in step S812, the control unit 100 checks whether a predetermined pattern of the imaging point Ps(3) can be detected from the image by image processing such as pattern matching.

[0094] If the predetermined pattern cannot be detected from the image (step S812: NO), control unit 100 changes the distance of infrared camera 81 in the Z direction from imaging point Ps(3) by driving infrared camera 81 in the Z direction using Z-axis camera motor 892 (step S813). Then, steps S811 to S813 are repeated until the predetermined pattern is detected (step S812: YES).

[0095] If the predetermined pattern is detected in step S812 (YES), the control unit 100 calculates the position (X, Y, Z) of the imaging point Ps(3) based on the predetermined pattern detected from the image acquired by imaging the imaging point Ps(3) (step S814). As a result, the positions (X, Y, Z) of the three imaging points Ps(1), Ps(2), and Ps(3) are acquired. In step S815, a plane passing through these three positions (X, Y, Z) is identified as the plane of the chuck stage 3, specifically, the plane representing the upper surface 311 of the suction plate 31.

[0096] In step S702 of the calibration in Fig. 13A, substrate plane identification (Fig. 13C) is performed. As shown in Fig. 13C, in the substrate plane identification, a count value I for identifying a plurality (three) of imaging points Pw(I) on the semiconductor substrate W is reset to zero (step S901), and the count value I is incremented by 1 (step S902). The imaging points Pw(I) are, for example, an area having a predetermined pattern.

[0097] Specifically, as shown in FIG. 12, the semiconductor substrate W is divided into a lattice shape by mutually orthogonal division lines S (Sa, Sb). That is, the semiconductor substrate W is provided with a plurality of parallel division lines Sa and a plurality of parallel division lines Sb, and the division lines Sa and Sb are orthogonal to each other. Thus, a plurality of semiconductor chips C are arranged in a lattice shape on either side of the division lines Sa and Sb. In contrast, an area including an intersection of the division lines Sa and Sb (in other words, a point surrounded by the semiconductor chips C arranged at the four corners) is set as the imaging point Pw(I). As described above, since the back surface of the semiconductor substrate W faces upward, the infrared camera 81 images the division lines Sa and Sb and the semiconductor chips C formed on the front surface of the semiconductor substrate W through the back surface of the semiconductor substrate W with infrared rays.

[0098] In step S903, the control unit 100 adjusts the position of the chuck stage 3 by the XYθ drive table 6, so that the imaging point Pw(I) faces the infrared camera 81 from below. This brings the imaging point Pw(I) into the field of view of the infrared camera 81. In step S903, the infrared camera 81 captures an image of the imaging point Pw(I) and obtains an image showing the imaging point Pw(I). In step S904, the control unit 100 checks whether a predetermined pattern of the imaging point Pw(I) (for example, a pattern where the planned division line Sa and the planned division line Sb intersect) can be detected from the image by image processing such as pattern matching.

[0099] If the focus of the infrared camera 81 is shifted from the imaging point Pw(I) and the predetermined pattern cannot be detected from the image ("NO" in step S904), the control unit 100 changes the distance of the infrared camera 81 in the Z direction from the imaging point Pw(I) by driving the infrared camera 81 in the Z direction using the Z-axis camera motor 892 (step S905). This changes the focus of the infrared camera 81 in the Z direction. Steps S903 to S905 are repeated until the infrared camera 81 focuses on the imaging point Pw(I) and the predetermined pattern is detected ("YES" in step S904).

[0100] Incidentally, a plane (stage plane) representing the upper surface 311 of the suction plate 31 has been specified by the previously executed stage plane specification ( FIG. 13B ). Therefore, the height range in which the imaging point Pw(I) of the semiconductor substrate W placed on the suction plate 31 exists can be estimated based on this stage plane. Therefore, in step S805, the height of the infrared camera 81 is changed so that the focus of the infrared camera 81 falls within the range in which the imaging point Pw(I) exists, which is estimated from the stage plane.

[0101] In step S906, the control unit 100 calculates the position (X, Y, Z) of the imaging point Pw(I) based on the predetermined pattern detected from the image acquired by imaging the imaging point Pw(I). The X and Y coordinates of the imaging point Pw(I) are calculated based on the position of the predetermined pattern included in the image. The Z coordinate of the imaging point Pw(I) is calculated based on the position in the Z direction of the infrared camera 81 when the image in which the predetermined pattern was detected was captured.

[0102] In step S907, it is confirmed whether the count value I has reached 2, i.e., whether the positions (X, Y, Z) of the two imaging points Pw(1) and Pw(2) have been acquired. If the count value I is less than 2 ("NO" in step S907), the process returns to step S902, and steps S902 to S906 are executed. If the count value I is 2 ("YES" in step S907), the process proceeds to step S908.

[0103] In step S908, a rotation angle θb for rotating the chuck stage 3 in the θ direction is calculated based on the two image capture points Pw(1) and Pw(2) so that the planned division line Sa is parallel to the X direction (machining direction). If the difference between the current rotation angle of the suction plate 31 (the actual rotation angle and the rotation angle θb) is not zero ("NO" in step S909), the chuck stage 3 is rotated by the rotation angle θb (step S910), and the process returns to step S901. In this manner, steps S901 to S909 are executed.

[0104] If the difference between the current rotation angle of the suction plate 31 (the actual rotation angle and the rotation angle θb) is zero (YES in step S909), the process proceeds to step S911. In step S911, the control unit 100 captures an image of the imaging point Pw(3) using the infrared camera 81 in the same manner as in step S903, and obtains an image showing the imaging point Pw(3). Then, in step S912, the control unit 100 checks whether a predetermined pattern of the imaging point Pw(3) can be detected from the image by image processing such as pattern matching.

[0105] If the predetermined pattern cannot be detected from the image (step S912: NO), the control unit 100 drives the infrared camera 81 in the Z direction by the Z-axis camera motor 892, thereby changing the distance of the infrared camera 81 in the Z direction from the imaging point Pw(3) (step S913). Then, steps S911 to S913 are repeated until the predetermined pattern is detected (step S912: YES). At this time, the range for changing the height of the infrared camera 81 is set based on the stage plane, as described above.

[0106] If the predetermined pattern is detected in step S912 (YES), the control unit 100 calculates the position (X, Y, Z) of the imaging point Pw(3) based on the predetermined pattern detected from the image acquired by imaging the imaging point Pw(3) (step S914). As a result, the positions (X, Y, Z) of the three imaging points Pw(1), Pw(2), and Pw(3) are acquired. In step S915, a plane passing through these three positions (X, Y, Z) is identified as a plane representing the semiconductor substrate W.

[0107] Returning to FIG. 11, the description will be continued. When the semiconductor substrate W is positioned so that the planned division lines Sa are parallel to the X direction by the execution of the above calibration, and a plane representing the semiconductor substrate W is specified (step S601), a line processing process (step S602) is executed for each planned division line Sa. That is, a line processing process is executed in which the laser irradiation position Lb is moved in the X direction along the target planned division line Sa and the laser light B is irradiated to the laser irradiation position Lb while changing the target planned division line Sa among the multiple planned division lines Sa, and processing is executed with the laser light B on each of the multiple planned division lines Sa. In particular, as shown in the column of step S602 in FIG. 12, a line processing process in which the laser irradiation position Lb is moved to the (+X) side in the X direction and a line processing process in which the laser irradiation position Lb is moved to the (-X) side in the X direction are executed alternately.

[0108] At this time, the movement of the laser light B to the (+X) side with respect to the dividing line Sa is performed by driving the chuck stage 3 holding the semiconductor substrate W to the (-X) side by the X-axis driving unit 65, and the movement of the laser light B to the (-X) side with respect to the dividing line Sa is performed by driving the chuck stage 3 holding the semiconductor substrate W to the (+X) side by the X-axis driving unit 65. In addition, the change of the dividing line Sa to be the target of the line processing is performed by driving the chuck stage 3 holding the semiconductor substrate W in the Y direction by the Y-axis driving unit 63. In addition, the control unit 100 controls the Z-axis head motor 792 to adjust the position of the processing head 71 in the Z direction based on the plane representing the semiconductor substrate W specified by the calibration in step S601. As a result, the focusing position of the laser light B is adjusted inside the semiconductor substrate W, and a modified layer is formed inside the semiconductor substrate W along the dividing line Sa.

[0109] In this way, when the line processing for each of the plurality of planned division lines Sa is completed (step S602), the chuck stage 3 holding the semiconductor substrate W is rotated by 90 degrees in the θ direction by the θ-axis table motor 66. This switches the state from one in which the plurality of planned division lines Sa on which the laser processing has been performed are positioned parallel to the X direction (the column "S602_e" in FIG. 12) to one in which the plurality of planned division lines Sb are positioned parallel to the X direction (the column "S603" in FIG. 12).

[0110] In step S604, calibration is performed in the same manner as in step S601 described above. Also, in step S605, line processing is performed on each of the plurality of planned division lines Sb in the same manner as in step S602 described above.

[0111] Fig. 14 is a flow chart showing basic steps of line processing for each division line, and Fig. 15A is a diagram showing a first example of the operation executed according to the flow chart of Fig. 14. In Fig. 15A, the locus of the laser irradiation position Lb that moves relatively to the semiconductor substrate W is shown by a dotted line, and virtual straight lines Sv1, Sv2, Sv3 extending parallel to the X direction between both outer sides of the division lines S1, S2, S3 along the division lines S1, S2, S3 are shown by a dashed line. Note that in the part where the locus of the laser irradiation position Lb and the virtual straight lines Sv1, Sv2, Sv3 overlap, the dotted line showing the locus of the laser irradiation position Lb is preferentially shown.

[0112] In the example shown in Fig. 15A, the flow chart of Fig. 14 starts 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 provided on a virtual straight line Sv1 along the planned division line S1, in other words, a position facing the planned division line S1 from the X direction. However, the position of the laser irradiation position Lb when starting the flow chart of Fig. 14 is not limited to this example and can be changed as appropriate.

[0113] In step S1001, the laser irradiation position Lb, which stops at position Pb1, starts accelerating toward the (+X) side in the X direction and moves parallel to the X direction. This causes the laser irradiation position Lb to move toward the (+X) side along the virtual straight line Sv1. Then, when the speed Vx of the laser irradiation position Lb increases to a processing speed Vxd before the laser irradiation position Lb reaches the end of the semiconductor substrate W on the (-X) side, the laser irradiation position Lb moves at a constant speed toward the (+X) side in the X direction at the processing speed Vxd (step S1002).

[0114] Furthermore, in synchronization with the timing when the laser irradiation position Lb reaches the end of the semiconductor substrate W on the (-X) side, the laser light source 72 is turned on, and irradiation of the laser light B from the processing head 71 to the laser irradiation position Lb is started (step S1003). In addition, in synchronization with the timing when the laser irradiation position Lb reaches the end of the semiconductor substrate W on the (+X) side, the laser light source 72 is turned off, and irradiation of the laser light B from the processing head 71 to the laser irradiation position Lb is terminated (step S1004). Thus, during the period from step S1003 to S1004, the laser irradiation position Lb is irradiated with the laser light B while the laser irradiation position Lb moves along the planned division line S1 to the (+X) side, and laser processing is performed on the planned division line S1 (line processing process).

[0115] When the laser irradiation position Lb passes the planned dividing line S1 on the (+X) side, the laser irradiation position Lb starts to decelerate toward the (+X) side in the X direction (step S1005), and the laser irradiation position Lb stops at a position Pb2 on the (+X) side of the semiconductor substrate W in the X direction (step S1006). This position Pb2 is provided on the virtual line Sv2 adjacent to the virtual line Sv1 in the Y direction, in other words, a position facing the planned dividing line S2 from the X direction. That is, in steps S1005 to S1006, the laser irradiation position Lb moves in the Y direction from the virtual line Sv1 to the virtual line Sv2 in parallel with the deceleration in the X direction.

[0116] Incidentally, the positional relationship between the imaging range Ri (FIG. 1) of the imaging units 8A and 8B and the laser irradiation position Lb of the processing head 71 is fixed. Therefore, in steps S1001 to S1006, as the laser irradiation position Lb moves relative to the semiconductor substrate W, the imaging range Ri also moves relative to the semiconductor substrate W. Then, in a state where the laser irradiation position Lb stops at the position Pb2, the imaging range Ri of the imaging unit 8B stops at a position including at least the 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 perpendicular to the planned division line S intersect on the semiconductor substrate W. Therefore, in step S1006, the control unit 100 causes the imaging unit 8B to image the imaging range Ri to obtain an image including the imaging point Pw (S2). As a result, the control unit 100 can obtain an image showing the position of the planned division line S2 that is not yet processed.

[0117] In step S1007, it is confirmed whether or not laser processing has been completed for a plurality of division lines S parallel to the X direction. If there are any unprocessed division lines S among these division lines S (if "NO" in step S1007), the process returns to step S1001.

[0118] 15A, in step S1001, the laser irradiation position Lb stopped at position Pb2 starts accelerating toward the (-X) side in the X direction and moves parallel to the X direction. This causes the laser irradiation position Lb to move toward the (-X) side along the virtual straight line Sv2. Then, when the speed Vx of the laser irradiation position Lb increases to a processing speed Vxd before the laser irradiation position Lb reaches the end of the semiconductor substrate W on the (+X) side, the laser irradiation position Lb moves at a constant speed toward the (-X) side in the X direction at the processing speed Vxd (step S1002).

[0119] Here, in the X direction, the position where the laser irradiation position Lb that has passed the planned division line S1 to the (+X) side starts to decelerate (in other words, the X coordinate where the uniform speed movement to the (+X) side ends) coincides with the position where the laser irradiation position Lb that accelerates to the (-X) side toward the planned division line S ends its acceleration (in other words, the X coordinate where the uniform speed movement to the (-X) side starts) coincides with the X direction where the laser irradiation position Lb that has passed the planned division line Sn on which the nth line processing is performed ends its uniform speed movement and starts to decelerate, and coincides with the X direction where the laser irradiation position Lb toward the planned division line Sn+1 on which the n+1th line processing is performed ends its acceleration and starts its uniform speed movement.

[0120] Furthermore, in synchronization with the timing when the laser irradiation position Lb reaches the end of the semiconductor substrate W on the (+X) side, the laser light source 72 is turned on, and irradiation of the laser light B from the processing head 71 to the laser irradiation position Lb is started (step S1003). In addition, in synchronization with the timing when the laser irradiation position Lb reaches the end of the semiconductor substrate W on the (-X) side, the laser light source 72 is turned off, and irradiation of the laser light B from the processing head 71 to the laser irradiation position Lb is terminated (step S1004). Thus, during the period from step S1003 to S1004, the laser irradiation position Lb is irradiated with the laser light B while the laser irradiation position Lb moves along the planned division line S2 to the (-X) side, and laser processing is performed on the planned division line S2 (line processing process).

[0121] When the laser irradiation position Lb passes the planned dividing line S2 on the (-X) side, the laser irradiation position Lb starts to decelerate toward the (-X) side in the X direction (step S1005), and the laser irradiation position Lb stops at a position Pb3 on the (-X) side of the semiconductor substrate W in the X direction (step S1006). This position Pb3 is provided on the virtual line Sv3 adjacent to the virtual line Sv2 in the Y direction, in other words, a position facing the planned dividing line S3 from the X direction. That is, in steps S1005 to S1006, the laser irradiation position Lb moves in the Y direction from the virtual line Sv2 to the virtual line Sv3 in parallel with the deceleration in the X direction.

[0122] Moreover, in a state where the laser irradiation position Lb stops at the position Pb3, the imaging range Ri of the imaging unit 8A stops at a position including at least the imaging point Pw (S3). This imaging point Pw (S3) is an intersection of the planned division line S3 and the planned division line S perpendicular to the planned division line S on the semiconductor substrate W. Therefore, in step S1006, the control unit 100 causes the imaging unit 8A to image the imaging range Ri to obtain an image including the imaging point Pw (S3). This allows the control unit 100 to obtain an image showing the position of the unprocessed planned division line S3.

[0123] Then, steps S1001 to S1007 are repeated until it is confirmed that the laser processing is completed for a plurality of planned division lines S (S1, S2, S3, . . . ) parallel to the X direction ("YES" in step S1007).

[0124] Next, the speed change of the laser irradiation position Lb will be described with reference to "speed change in X direction" and "speed change in Y direction" in Fig. 15A. Here, the speed Vx indicates the speed at which the laser irradiation position Lb moves in the X direction relative to the semiconductor substrate W, and the speed Vy indicates the speed at which the laser irradiation position Lb moves in the Y direction relative to the semiconductor substrate W. Moreover, the processing speed Vxd indicates the speed at which the laser irradiation position Lb moves at a constant speed in the X direction along the intended division line S (i.e., the speed Vx), and is expressed as an absolute value regardless of whether the laser irradiation position Lb moves to the (+X) side or the (-X) side.

[0125] In a line processing period Ts1 (steps S1002 to S1004) in which a line processing process is performed to move the laser light B to the (+X) side along the planned division line S1, the laser irradiation position Lb moves in the X direction at a constant processing speed Vxd but does not move in the Y direction. Also, in a line processing period Ts2 (steps S1002 to S1004) in which a line processing process is performed to move the laser light B to the (-X) side along the planned division line S2, the laser irradiation position Lb moves in the X direction at a constant processing speed Vxd but does not move in the Y direction.

[0126] In addition, during a switching period Tc (steps S1005, S1006, S1001) when the line processing period Ts1 is switched to the line processing period Ts2, the following operation is executed. That is, the X-axis drive unit 65 (processing axis drive unit) decelerates the laser irradiation position Lb that has passed the division line S1 (first processing line) toward the (+X) side (first side) in the X direction (processing direction) toward the (+X) side, stops it (step S1005), and then accelerates it toward the (-X) side (step S1001), thereby executing a reversal drive to bring the laser irradiation position Lb to the division line S2 (second processing line). In parallel with this reversal drive, the Y-axis drive unit 63 (feed axis drive unit) moves the laser irradiation position Lb in the Y direction (feed direction) from a virtual straight line Sv1 (first virtual straight line) extending in the X direction along the planned division line S1 to the outside of the planned division line S1 to a virtual straight line Sv2 (second virtual straight line) extending in the X direction along the planned division line S2 (second processing line) to the outside of the planned division line S2.

[0127] In particular, the switching period Tc includes a deceleration period Td (step S1005) in which the laser irradiation position Lb is decelerated in the X direction, and an acceleration period Ta (step S1001) in which the laser irradiation position Lb is accelerated in the X direction, and the movement of the laser irradiation position Lb in the Y direction is executed during the deceleration period Td out of the deceleration period Td and the acceleration period Ta. Specifically, the movement of the laser irradiation position Lb in the Y direction starts after the deceleration period Td starts, and the movement of the laser irradiation position Lb in the Y direction ends before the deceleration period Td ends. Moreover, the laser irradiation position Lb does not move in the Y direction during the acceleration period Ta.

[0128] Here, the start of the deceleration period Td indicates the time when the laser irradiation position Lb starts to decelerate in the X direction (in other words, the absolute value of the speed Vx decreases from the processing speed Vxd), and the end of the deceleration period Td indicates the time when the speed of the laser irradiation position Lb in the X direction (in other words, the speed Vx) becomes zero. The start of the acceleration period Ta indicates the time when the laser irradiation position Lb starts to accelerate in the X direction (in other words, the absolute value of the speed Vx increases from zero), and the end of the acceleration period Ta indicates the time when the acceleration of the laser irradiation position Lb in the X direction ends (in other words, the absolute value of the speed Vx becomes the processing speed Vxd).

[0129] During a stop period Tt provided during the transition from the acceleration period Ta to the deceleration period Td, both the velocity Vx in the X direction and the velocity Vy in the Y direction of the laser irradiation position Lb become zero, and the laser irradiation position Lb stops at position Pb2 relative to the semiconductor substrate W. During this stop period Tt, the imaging range Ri of the imaging units 8A and 8B also stops relative to the semiconductor substrate W, and in particular, the imaging range Ri of the imaging unit 8B is located on the (-X) side of the laser irradiation position Lb located on the (+X) side of the semiconductor substrate W, overlapping with the semiconductor substrate W. Therefore, during the stop period Tt, the infrared camera 81 of the imaging unit 8B images a portion of the semiconductor substrate W that overlaps with the imaging range Ri (step S1006).

[0130] FIG. 15B is a diagram showing a second example of the operation performed according to the flowchart of FIG. 14. The notation in FIG. 15B is the same as that in FIG. 15A. In FIG. 15B, the laser processing is performed in order on the division lines S1, S2, and S3 according to the flowchart of FIG. 14, as in FIG. 15A. However, the operation in the switching period Tc for changing the division line S to be subjected to the laser processing is different between FIG. 15B and FIG. 15A. Therefore, the difference from FIG. 15A will be mainly described, and the common operations will be denoted by corresponding symbols and the description thereof will be omitted as appropriate.

[0131] When the laser irradiation position Lb passes the planned division line S1 toward the (+X) side with the end of the laser processing on the planned division line S1, the laser irradiation position Lb starts to decelerate toward the (+X) side in the X direction (step S1005), and the laser irradiation position Lb stops at a position Pb2 on the (+X) side of the semiconductor substrate W in the X direction (step S1006). This position Pb2 is provided on the virtual straight line Sv1. In addition, in a state where the laser irradiation position Lb stops at the position Pb2, the imaging range Ri of the imaging unit 8B stops at a position that includes at least the imaging point Pw (S2). Therefore, in step S1006, the control unit 100 causes the imaging unit 8B to image the imaging range Ri to obtain an image including the imaging point Pw (S2). As a result, the control unit 100 can obtain an image showing the position of the unprocessed planned division line S2.

[0132] Next, the laser irradiation position Lb, which stops at the position Pb2, starts accelerating toward the (-X) side in the X direction (step S1001). Then, when the speed Vx of the laser irradiation position Lb increases to the processing speed Vxd before the laser irradiation position Lb reaches the end of the semiconductor substrate W on the (+X) side, the laser irradiation position Lb moves at a constant speed toward the (-X) side in the X direction at the processing speed Vxd (step S1002). In addition, during the period from when the laser irradiation position Lb starts accelerating to when it starts moving at a constant speed at the processing speed Vxd, the laser irradiation position Lb moves in the Y direction from the virtual straight line Sv1 to the virtual straight line Sv2. That is, in steps S1001 to S1002, the laser irradiation position Lb moves in the Y direction from the virtual straight line Sv1 to the virtual straight line Sv2 in parallel with the acceleration in the X direction. As a result, the laser irradiation position Lb reaches the planned division line S2, and line processing on the planned division line S2 can be started.

[0133] When the laser irradiation position Lb passes the planned division line S2 to the (-X) side with the end of the laser processing on the planned division line S2, the laser irradiation position Lb starts to decelerate toward the (-X) side in the X direction (step S1005), and the laser irradiation position Lb stops at a position Pb3 on the (-X) side of the semiconductor substrate W in the X direction (step S1006). This position Pb3 is provided on the virtual straight line Sv2. In addition, in a state where the laser irradiation position Lb stops at the position Pb3, the imaging range Ri of the imaging unit 8A stops at a position that includes at least the imaging point Pw (S3). Therefore, in step S1006, the control unit 100 causes the imaging unit 8A to image the imaging range Ri to obtain an image including the imaging point Pw (S3). As a result, the control unit 100 can obtain an image showing the position of the unprocessed planned division line S3.

[0134] Next, the speed change of the laser irradiation position Lb will be described with reference to "speed change in X direction" and "speed change in Y direction" in Fig. 15B. In a line processing period Ts1 (steps S1002 to S1004) in which a line processing process is performed to move the laser light B to the (+X) side along the division line S1, the laser irradiation position Lb moves in the X direction at a constant processing speed Vxd but does not move in the Y direction. In addition, in a line processing period Ts2 (steps S1002 to S1004) in which a line processing process is performed to move the laser light B to the (-X) side along the division line S2, the laser irradiation position Lb moves in the X direction at a constant processing speed Vxd but does not move in the Y direction.

[0135] Also, in a switching period Tc (steps S1005, S1006, 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 virtual straight line Sv1 to the virtual straight line Sv2 in parallel with the inversion drive in the X direction as described above. In particular, of the deceleration period Td and acceleration period Ta included in the switching period Tc, the movement of the laser irradiation position Lb in the Y direction is executed during the acceleration period Ta. Specifically, the movement of the laser irradiation position Lb in the Y direction starts after the acceleration period Ta starts, and the movement of the laser irradiation position Lb in the Y direction ends before the acceleration period Ta ends. Moreover, the laser irradiation position Lb does not move in the Y direction during the deceleration period Td.

[0136] During a stop period Tt provided during the transition from the acceleration period Ta to the deceleration period Td, both the velocity Vx in the X direction and the velocity Vy in the Y direction of the laser irradiation position Lb become zero, and the laser irradiation position Lb stops at position Pb2 relative to the semiconductor substrate W. During this stop period Tt, the imaging range Ri of the imaging units 8A and 8B also stops relative to the semiconductor substrate W, and in particular, the imaging range Ri of the imaging unit 8B is located on the (-X) side of the laser irradiation position Lb located on the (+X) side of the semiconductor substrate W, overlapping with the semiconductor substrate W. Therefore, during the stop period Tt, the infrared camera 81 of the imaging unit 8B images a portion of the semiconductor substrate W that overlaps with the imaging range Ri (step S1006).

[0137] FIG. 15C is a diagram showing a third example of the operation performed according to the flowchart of FIG. 14. The notation in FIG. 15C is the same as that in FIG. 15A. In FIG. 15C, the laser processing is performed in order on the division lines S1, S2, and S3 according to the flowchart of FIG. 14, as in FIG. 15A. However, the operation in the switching period Tc for changing the division line S to be subjected to the laser processing is different between FIG. 15C and FIG. 15A. Therefore, the difference from FIG. 15A will be mainly described, and the common operations will be denoted by corresponding symbols and the description will be omitted as appropriate.

[0138] When the laser irradiation position Lb passes the division line S1 on the (+X) side with the completion of the laser processing on the division line S1, the laser irradiation position Lb starts to decelerate toward the (+X) side in the X direction (step S1005), and the laser irradiation position Lb stops at a position Pb2 on the (+X) side of the semiconductor substrate W in the X direction (step S1006). This position Pb2 is provided between the virtual straight lines Sv1 and Sv2 in the Y direction. That is, in steps S1005 to S1006, the laser irradiation position Lb moves in the Y direction from the virtual straight line Sv1 to the position Pb2 in parallel with the deceleration in the X direction. In addition, when the laser irradiation position Lb stops at the position Pb2, the imaging range Ri of the imaging unit 8B stops at a position including at least the imaging point Pw(S2). Therefore, in step S1006, the control unit 100 causes the imaging unit 8B to capture the imaging range Ri and obtain an image including the imaging point Pw(S2). This allows the control unit 100 to obtain an image indicating the position of the unprocessed planned division line S2.

[0139] Next, the laser irradiation position Lb, which stops at the position Pb2, starts accelerating toward the (-X) side in the X direction (step S1001). Then, when the speed Vx of the laser irradiation position Lb increases to the processing speed Vxd before the laser irradiation position Lb reaches the end of the semiconductor substrate W on the (+X) side, the laser irradiation position Lb moves at a constant speed toward the (-X) side in the X direction at the processing speed Vxd (step S1002). In addition, during the period from when the laser irradiation position Lb starts accelerating to when it starts moving at a constant speed at the processing speed Vxd, the laser irradiation position Lb moves in the Y direction from the position Pb2 to the virtual straight line Sv2. That is, in steps S1001 to S1002, the laser irradiation position Lb moves in the Y direction from the position Pb2 to the virtual straight line Sv2 in parallel with the acceleration in the X direction. As a result, the laser irradiation position Lb reaches the planned division line S2, and line processing on the planned division line S2 can be started.

[0140] When the laser irradiation position Lb passes the planned division line S2 on the (-X) side with the completion of the laser processing on the planned division line S2, the laser irradiation position Lb starts to decelerate toward the (-X) side in the X direction (step S1005), and the laser irradiation position Lb stops at a position Pb3 on the (-X) side of the semiconductor substrate W in the X direction (step S1006). This position Pb3 is provided between the virtual straight lines Sv2 and Sv3 in the Y direction. That is, in steps S1005 to S1006, the laser irradiation position Lb moves in the Y direction from the virtual straight line Sv2 to position Pb3 in parallel with the deceleration in the X direction. In addition, when the laser irradiation position Lb stops at position Pb3, the imaging range Ri of the imaging unit 8A stops at a position including at least the imaging point Pw(S3). Therefore, in step S1006, the control unit 100 causes the imaging unit 8A to capture an image of the imaging range Ri and obtain an image including the imaging point Pw(S3). This allows the control unit 100 to obtain an image indicating the position of the unprocessed planned division line S3.

[0141] Next, the speed change of the laser irradiation position Lb will be described with reference to "speed change in X direction" and "speed change in Y direction" in Fig. 15C. In a line processing period Ts1 (steps S1002 to S1004) in which a line processing process is performed to move the laser light B to the (+X) side along the division line S1, the laser irradiation position Lb moves in the X direction at a constant processing speed Vxd but does not move in the Y direction. In addition, in a line processing period Ts2 (steps S1002 to S1004) in which a line processing process is performed to move the laser light B to the (-X) side along the division line S2, the laser irradiation position Lb moves in the X direction at a constant processing speed Vxd but does not move in the Y direction.

[0142] Also, in a switching period Tc (steps S1005, S1006, 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 virtual straight line Sv1 to the virtual straight line Sv2 in parallel with the inversion drive in the X direction as described above. In particular, this movement of the laser irradiation position Lb is executed via the position Pb2. That is, of the deceleration period Td and the acceleration period Ta included in the switching period Tc, the laser irradiation position Lb moves in the Y direction from the virtual straight line Sv1 to the position Pb2 in the deceleration period Td, and the laser irradiation position Lb moves in the Y direction from the position Pb2 to the virtual straight line Sv2 in the acceleration period Ta. Specifically, the laser irradiation position Lb starts moving from the virtual straight line Sv1 to the position Pb2 at the same time as the deceleration period Td starts, and the laser irradiation position Lb reaches the position Pb2 at the same time as the deceleration period Td ends. Moreover, the laser irradiation position Lb starts moving from the position Pb2 to the imaginary line Sv2 at the same time as the acceleration period Ta starts, and the laser irradiation position Lb reaches the imaginary line Sv2 at the same time as the acceleration period Ta ends.

[0143] During a stop period Tt provided during the transition from the acceleration period Ta to the deceleration period Td, both the velocity Vx in the X direction and the velocity Vy in the Y direction of the laser irradiation position Lb become zero, and the laser irradiation position Lb stops at position Pb2 relative to the semiconductor substrate W. During this stop period Tt, the imaging range Ri of the imaging units 8A and 8B also stops relative to the semiconductor substrate W, and in particular, the imaging range Ri of the imaging unit 8B is located on the (-X) side of the laser irradiation position Lb located on the (+X) side of the semiconductor substrate W, overlapping with the semiconductor substrate W. Therefore, during the stop period Tt, the infrared camera 81 of the imaging unit 8B images a portion of the semiconductor substrate W that overlaps with the imaging range Ri (step S1006).

[0144] In addition, during the switching period Tc, the specific manner in which the image sensor 1 moves in the Y direction from the virtual straight line Sv1 to the position Pb2 and then moves in the Y direction from the position Pb2 to the virtual straight line Sv2 is not limited to the example of FIG. 15C, and this movement may be performed in the manner shown in, for example, FIG. 15D, FIG. 15E, and FIG. 15F.

[0145] Fig. 15D is a diagram showing a fourth example of the operation performed according to the flowchart of Fig. 14, Fig. 15E is a diagram showing a fifth example of the operation performed according to the flowchart of Fig. 14, and Fig. 15F is a diagram showing a sixth example of the operation performed according to the flowchart of Fig. 14. The notations in Fig. 15D to Fig. 15F are the same as those in Fig. 15C. The difference between Fig. 15D to Fig. 15F and Fig. 15C is the movement mode of the laser irradiation position Lb during the switching period Tc. Therefore, the difference with Fig. 15C will be mainly described, and the common operations will be denoted by corresponding symbols and appropriately omitted from description.

[0146] In the fourth example shown in FIG. 15D, the laser irradiation position Lb starts moving in the Y direction from the virtual straight line Sv1 to the position Pb2 at the same time as the deceleration period Td starts, and before the deceleration period Td ends, the laser irradiation position Lb reaches the position Pb2 in the Y direction and stops at the position Pb2 (i.e., the speed Vy is zero). However, after the laser irradiation position Lb reaches the position Pb2 in the Y direction, the deceleration period Td continues, and the laser irradiation position Lb continues moving in the X direction. In addition, after the acceleration period Ta starts, the laser irradiation position Lb starts moving in the Y direction from the position Pb2 to the virtual straight line Sv2, and at the same time as the acceleration period Ta ends, the laser irradiation position Lb reaches the virtual straight line Sv2. In other words, during the period ΔTy from the middle of the deceleration period Td to the middle of the acceleration period Ta, the laser irradiation position Lb stops in the Y direction (i.e., the speed Vy is zero).

[0147] In the fifth example shown in FIG. 15E, the laser irradiation position Lb starts moving in the Y direction from the virtual straight line Sv1 to the position Pb2 at the same time as the deceleration period Td starts, and before the deceleration period Td ends, the laser irradiation position Lb reaches the position Pb2 in the Y direction and stops at the position Pb2 (i.e., the speed Vy is zero). However, after the laser irradiation position Lb reaches the position Pb2 in the Y direction, the deceleration period Td continues, and the laser irradiation position Lb continues moving in the X direction. Also, the laser irradiation position Lb starts moving in the Y direction from the position Pb2 to the virtual straight line Sv2 at the same time as the acceleration period Ta starts, and the laser irradiation position Lb reaches the virtual straight line Sv2 at the same time as the acceleration period Ta ends. That is, during the period ΔTy from the middle of the deceleration period Td to the start of the acceleration period Ta, the laser irradiation position Lb stops in the Y direction (i.e., the speed Vy is zero).

[0148] In the fifth example shown in FIG. 15F, the laser irradiation position Lb starts moving in the Y direction from the virtual straight line Sv1 to the position Pb2 at the same time as the deceleration period Td starts. However, at the end of the deceleration period Td, the laser irradiation position Lb does not reach the position Pb2 in the Y direction. At the end of the deceleration period Td, the position (i.e., X coordinate) of the laser irradiation position Lb and the position (i.e., X coordinate) of the position Pb2 in the X direction coincide with each other. Therefore, the laser irradiation position Lb continues to move in the Y direction toward the position Pb2 even after the end of the deceleration period Td. Also, during the period from the end of the deceleration period Td to the time when the laser irradiation position Lb moves in the Y direction toward the position Pb2, the laser irradiation position Lb stops in the X direction (i.e., the speed Vx is zero). Then, at the same time when the laser irradiation position Lb reaches the position Pb2, the acceleration period Ta starts and the laser irradiation position Lb starts moving in the Y direction from the position Pb2 to the virtual straight line Sv2. Moreover, at the same time that the acceleration period Ta ends, the laser irradiation position Lb reaches the imaginary line Sv2.

[0149] FIG. 15G is a diagram showing a seventh example of the operation performed according to the flowchart of FIG. 14. The notation in FIG. 15G is the same as that in FIG. 15A. In FIG. 15G, the laser processing is performed in order on the division lines S1, S2, and S3 according to the flowchart of FIG. 14, as in FIG. 15A. However, the operation in the switching period Tc for changing the division line S to be subjected to the laser processing is different between FIG. 15G and FIG. 15A. Therefore, the difference from FIG. 15A will be mainly described, and the common operations will be denoted by corresponding symbols and appropriately omitted from description.

[0150] When the laser irradiation position Lb passes the dividing line S1 on the (+X) side with the end of the laser processing on the dividing line S1, the laser irradiation position Lb starts to decelerate toward the (+X) side in the X direction (step S1005), and the laser irradiation position Lb stops at a position Pb2 on the (+X) side of the semiconductor substrate W in the X direction (step S1006). This position Pb2 is provided outside the section between the virtual straight lines Sv1 and Sv2 in the Y direction (the opposite side of the virtual straight line Sv1 with respect to the virtual straight line Sv2). That is, in steps S1005 to S1006, the laser irradiation position Lb moves in the Y direction from the virtual straight line Sv1 to the position Pb2 beyond the virtual straight line Sv2 in parallel with the deceleration in the X direction. In addition, when the laser irradiation position Lb stops at the position Pb2, the imaging range Ri of the imaging unit 8B stops at a position including at least the imaging point Pw (S3). Therefore, in step S1006, the control unit 100 causes the imaging unit 8B to capture an image of the imaging range Ri to obtain an image including the imaging point Pw(S3). This allows the control unit 100 to obtain an image indicating the position of the unprocessed planned division line S3.

[0151] Next, the laser irradiation position Lb, which stops at the position Pb2, starts accelerating toward the (-X) side in the X direction (step S1001). Then, when the speed Vx of the laser irradiation position Lb increases to the processing speed Vxd before the laser irradiation position Lb reaches the end of the semiconductor substrate W on the (+X) side, the laser irradiation position Lb moves at a constant speed toward the (-X) side in the X direction at the processing speed Vxd (step S1002). In addition, during the period from when the laser irradiation position Lb starts accelerating to when it starts moving at a constant speed at the processing speed Vxd, the laser irradiation position Lb moves in the Y direction from the position Pb2 to the virtual straight line Sv2. That is, in steps S1001 to S1002, the laser irradiation position Lb moves in the Y direction from the position Pb2 to the virtual straight line Sv2 in parallel with the acceleration in the X direction. As a result, the laser irradiation position Lb reaches the planned division line S2, and line processing on the planned division line S2 can be started.

[0152] When the laser irradiation position Lb passes the dividing line S2 on the (-X) side with the end of the laser processing on the dividing line S2, the laser irradiation position Lb starts to decelerate toward the (-X) side in the X direction (step S1005), and the laser irradiation position Lb stops at a position Pb3 on the (-X) side of the semiconductor substrate W in the X direction (step S1006). This position Pb3 is provided outside the section between the virtual straight lines Sv2 and Sv3 in the Y direction (the opposite side of the virtual straight line Sv2 with respect to the virtual straight line Sv3). That is, in steps S1005 to S1006, the laser irradiation position Lb moves in the Y direction from the virtual straight line Sv2 to the position Pb2 beyond the virtual straight line Sv3 in parallel with the deceleration in the X direction. In addition, when the laser irradiation position Lb stops at the position Pb3, the imaging range Ri of the imaging unit 8A stops at a position including at least the imaging point Pw (S4). Therefore, in step S1006, the control unit 100 causes the imaging unit 8A to capture an image of the imaging range Ri and obtain an image including the imaging point Pw(S4). This allows the control unit 100 to obtain an image indicating the position of the unprocessed planned division line S4.

[0153] Next, the speed change of the laser irradiation position Lb will be described with reference to "Speed ​​change in X direction" and "Speed ​​change in Y direction" in Fig. 15G. In a line processing period Ts1 (steps S1002 to S1004) in which a line processing process is performed to move the laser light B to the (+X) side along the division line S1, the laser irradiation position Lb moves in the X direction at a constant processing speed Vxd but does not move in the Y direction. In addition, in a line processing period Ts2 (steps S1002 to S1004) in which a line processing process is performed to move the laser light B to the (-X) side along the division line S2, the laser irradiation position Lb moves in the X direction at a constant processing speed Vxd but does not move in the Y direction.

[0154] Also, in a switching period Tc (steps S1005, S1006, 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 virtual straight line Sv1 to the virtual straight line Sv2 in parallel with the inversion drive in the X direction as described above. In particular, this movement of the laser irradiation position Lb is executed via a position Pb2 provided outside the section between the virtual straight lines Sv1 and Sv2 in the Y direction. That is, of the deceleration period Td and the acceleration period Ta included in the switching period Tc, the laser irradiation position Lb moves in the Y direction from the virtual straight line Sv1 to the position Pb2 beyond the virtual straight line Sv2 during the deceleration period Td, and the laser irradiation position Lb moves in the Y direction from the position Pb2 to the virtual straight line Sv2 during the acceleration period Ta. Specifically, the laser irradiation position Lb starts moving from the virtual line Sv1 to the position Pb2 at the same time as the deceleration period Td starts, and reaches the position Pb2 at the same time as the deceleration period Td ends. Also, the laser irradiation position Lb starts moving from the position Pb2 to the virtual line Sv2 at the same time as the acceleration period Ta starts, and reaches the virtual line Sv2 at the same time as the acceleration period Ta ends.

[0155] During a stop period Tt provided during the transition from the acceleration period Ta to the deceleration period Td, both the velocity Vx in the X direction and the velocity Vy in the Y direction of the laser irradiation position Lb become zero, and the laser irradiation position Lb stops at position Pb2 relative to the semiconductor substrate W. During this stop period Tt, the imaging range Ri of the imaging units 8A and 8B also stops relative to the semiconductor substrate W, and in particular, the imaging range Ri of the imaging unit 8B is located on the (-X) side of the laser irradiation position Lb located on the (+X) side of the semiconductor substrate W, overlapping with the semiconductor substrate W. Therefore, during the stop period Tt, the infrared camera 81 of the imaging unit 8B images a portion of the semiconductor substrate W that overlaps with the imaging range Ri (step S1006).

[0156] In the above example, the position Pb2 is provided on the opposite side of the virtual line Sv1 with respect to the virtual line Sv2 in the Y direction. However, the position Pb2 may be provided on the opposite side of the virtual line Sv2 with respect to the virtual line Sv1 in the Y direction. In this case, during the deceleration period Td, the laser irradiation position Lb moves in the Y direction from the virtual line Sv1 to the position Pb2, and during the acceleration period Ta, the laser irradiation position Lb moves in the Y direction from the position Pb2 to the virtual line Sv2 beyond the virtual line Sv1. A similar change is possible for the position Pb3.

[0157] In the embodiment described in FIG. 14 and FIG. 15A to FIG. 15G, a line processing process (steps S1003 to S1004, first line processing process) for processing the planned division line S1 (first processing line) and a line processing process (steps S1003 to S1004, second processing line) for processing the planned division line S (steps S1003 to S1004, second processing line) are performed using an X-axis drive unit 65 (processing axis drive unit) that moves the laser irradiation position Lb in the X direction (processing direction) relative to the semiconductor substrate W (object to be processed) and a Y-axis drive unit 63 (feed axis drive unit) that moves the laser irradiation position Lb in the Y direction (feed direction) relative to the semiconductor substrate W. Specifically, while the Y-axis drive unit 63 irradiates the laser irradiation position Lb with the laser light B in a state where the laser irradiation position Lb is aligned with the planned division line S1, the X-axis drive unit 65 moves the laser irradiation position Lb toward the (+X) side (first side) in the X direction with respect to the semiconductor substrate W, thereby executing a line processing process on the planned division line S1. Next, while the Y-axis drive unit 63 irradiates the laser irradiation position Lb with the laser light B in a state where the laser irradiation position Lb is aligned with the planned division line S2, the X-axis drive unit 65 moves the laser irradiation position Lb toward the (-X) side (second side) in the X direction with respect to the semiconductor substrate W, thereby executing a line processing process on the planned division line S2. In addition, during a switching period Tc between the line processing process on the planned division line S1 and the line processing process on the planned division line S2, the X-axis drive unit 65 and the Y-axis drive unit 63 execute the following operations in order to move the laser irradiation position Lb that has passed the planned division line S1 toward the planned division line S2. That is, the X-axis driving unit 65 performs a reverse drive in the X direction to make the laser irradiation position Lb, which has passed the planned division line S1 on the (+X) side, decelerate toward the (+X) side, stop it, and then accelerate toward the (-X) side, thereby making the laser irradiation position Lb reach the planned division line S2 (steps S1006, S1001). Also, the Y-axis driving unit 63 moves the laser irradiation position Lb in the Y direction from a virtual straight line Sv1 (first virtual straight line) that is extended in the X direction along the planned division line S1 to the outside of the planned division line S1 to a virtual straight line Sv2 (second virtual straight line) that is extended in the X direction along the planned division line S2 to the outside of the planned division line S2.

[0158] Furthermore, the semiconductor substrate W is imaged by the imaging unit 8B, which images an imaging range Ri that moves relatively to the semiconductor substrate W together with the laser irradiation position Lb as the laser irradiation position Lb moves relative to the semiconductor substrate W (step S1006). In particular, the imaging range Ri is located on the (-X) side of the laser irradiation position Lb in the X direction, and the imaging unit 8B images a portion (imaging point Pw) of the semiconductor substrate W that overlaps with the imaging range Ri during the switching period Tc. In this way, the switching period Tc is effectively used for imaging the semiconductor substrate W. As a result, it is possible to suppress the effect of the switching period Tc for switching the moving direction of the laser light B on the time required to complete processing of the semiconductor substrate W.

[0159] Furthermore, during the switching period Tc, the control unit 100 causes the Y-axis drive unit 63 to stop the laser irradiation position Lb, overlapping with the timing at which the X-axis drive unit 65 stops the laser irradiation position Lb by the reverse drive, thereby providing a stop period Tt during which the laser irradiation position Lb stops in both the X and Y directions. During the stop period Tt, the imaging unit 8B images a portion of the semiconductor substrate W that overlaps with the imaging range Ri. With this configuration, a still image of the semiconductor substrate W can be obtained by effectively utilizing the switching period Tc.

[0160] Moreover, the same operation as above is also executed during a switching period Tc from the line processing for the division line S2 to the line processing for the division line S3, and the imaging section 8A images the semiconductor substrate W.

[0161] 15A, during the switching period Tc, the Y-axis driver 63 finishes moving the laser irradiation position Lb from the virtual straight line Sv1 to the virtual straight line Sv2 before the X-axis driver 65 stops the laser irradiation position Lb in the reverse drive. In this configuration, the switching period Tc can be effectively used to acquire a still image of the semiconductor substrate W.

[0162] 15B, in the switching period Tc, after the X-axis drive unit 65 stops the laser irradiation position Lb in the reverse drive, the Y-axis drive unit 63 starts moving the laser irradiation position Lb from on the virtual straight line Sv1 to on the virtual straight line Sv2. In this configuration, the switching period Tc can be effectively used to acquire a still image of the semiconductor substrate W.

[0163] 15C to 15G, the Y-axis driver 63 moves the laser irradiation position Lb from on the virtual straight line Sv1 to on the virtual straight line Sv2 so that the laser irradiation position Lb passes through a position Pb2 (temporary stop position) different in the Y direction from both the virtual straight lines Sv1 and Sv2. The controller 100 then controls the X-axis driver 65 and the Y-axis driver 63 so that the Y-axis driver 63 stops the laser irradiation position Lb at the temporary stop position at the same time that the X-axis driver 65 stops the laser irradiation position Lb by the reverse drive, thereby providing a stop period Tt. With this configuration, the switching period Tc can be effectively used to acquire a still image of the semiconductor substrate W.

[0164] FIG. 16 is a flow chart showing a first application example of the line processing process for each division planned line, and FIG. 17 is a diagram showing an example of the operation executed according to the flow chart of FIG. 16. The notation in FIG. 17 is the same as that in FIG. 15A to FIG. 15G. The example of FIG. 16 and the example of FIG. 14 differ in the presence or absence of step S1008 for imaging the semiconductor substrate W during the line processing process, but are common in other steps S1001 to S1007. Therefore, in the example of FIG. 16, any of the operations (first to seventh examples) shown in FIG. 15A to FIG. 15G is executed. Note that FIG. 17 does not show the trajectory of the laser irradiation position Lb during the switching period Tc, but the laser irradiation position Lb can move along any of the trajectories shown in FIG. 15A to FIG. 15G.

[0165] Step S1008 in FIG. 16 is executed as follows. That is, the semiconductor substrate W is imaged while the laser irradiation position Lb is moving along the planned division line S1 (step S1008). Specifically, an image is captured of the imaging range Ri (i.e., the imaging range Ri of the imaging unit 8A) located on the moving side of the laser irradiation position Lb (i.e., the (+X) side) of the laser irradiation position Lb moving to the (+X) side. This allows an image to be acquired that includes an imaging point Pw (S11) on the moving side of the laser irradiation position Lb than the laser irradiation position Lb. In this way, an image showing the position of the unprocessed portion of the planned division line S1 during the line processing process can be acquired.

[0166] That is, during the execution periods of steps S1003, S1108, and S1104, while the line processing process is being executed on the planned division line S1, an image of the unprocessed portion of the planned division line S1 that is the target of the line processing process is captured.

[0167] Moreover, the semiconductor substrate W is imaged while the laser irradiation position Lb is moving along the planned division line S2 (step S1008). Specifically, an image is captured of the imaging range Ri (i.e., the imaging range Ri of the imaging unit 8B) located on the moving side of the laser irradiation position Lb (i.e., the (-X) side) of the laser irradiation position Lb moving to the (-X) side. This allows an image to be acquired that includes an imaging point Pw (S21) on the moving side of the laser irradiation position Lb. In this way, an image showing the position of the unprocessed portion of the planned division line S2 during the line processing process can be acquired.

[0168] That is, during the execution periods of steps S1003, S1108, and S1104, the line processing is executed on the planned division line S2, and in parallel therewith, an image of an unprocessed portion of the planned division line S2 that is the target of the line processing is captured.

[0169] Furthermore, the semiconductor substrate W is imaged while the laser irradiation position Lb is moving along the planned division line S3 (step S1008). Specifically, an image is captured of the imaging range Ri (i.e., the imaging range Ri of the imaging unit 8A) located on the moving side of the laser irradiation position Lb (i.e., the (+X) side) of the laser irradiation position Lb moving to the (+X) side. This allows an image to be acquired that includes an imaging point Pw (S31) on the moving side of the laser irradiation position Lb. In this way, an image showing the position of the unprocessed portion of the planned division line S3 during the line processing process can be acquired.

[0170] That is, during the execution periods of steps S1003, S1108, and S1104, the line processing is executed on the planned division line S3, and in parallel therewith, an image of an unprocessed portion of the planned division line S3 that is the target of the line processing is captured.

[0171] Then, steps S1001 to S1007 are repeated until it is confirmed that the laser processing is completed for a plurality of planned division lines S (S1, S2, S3, . . . ) parallel to the X direction ("YES" in step S1007).

[0172] Fig. 18 is a flow chart showing a second application example of the line processing process for each division line, and Fig. 19A is a diagram showing a first example of the operation executed according to the flow chart of Fig. 18. In Fig. 19A, the locus of the laser irradiation position Lb that moves relatively to the semiconductor substrate W is shown by a dotted line, and virtual straight lines Sv1, Sv2, and Sv3 extending parallel to the X direction between both outer sides of the division lines S1, S2, and S3 along the division lines S1, S2, and S3 are shown by a dashed line. Note that in the part where the locus of the laser irradiation position Lb and the virtual straight lines Sv1, Sv2, and Sv3 overlap, the dotted line showing the locus of the laser irradiation position Lb is preferentially shown.

[0173] In the example shown in Fig. 19A, the flow chart of Fig. 18 starts 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 provided on a virtual straight line Sv1 along the planned division line S1, in other words, a position facing the planned division line S1 from the X direction. However, the position of the laser irradiation position Lb when starting the flow chart of Fig. 18 is not limited to this example and can be changed as appropriate.

[0174] In step S1101, the laser irradiation position Lb stopped at position Pb1 starts accelerating toward the (+X) side in the X direction and moves parallel to the X direction. This causes the laser irradiation position Lb to move toward the (+X) side along the virtual straight line Sv1. Then, when the speed Vx of the laser irradiation position Lb increases to the processing speed Vxd before the laser irradiation position Lb reaches the end of the semiconductor substrate W on the (-X) side, the laser irradiation position Lb moves at a constant speed toward the (+X) side in the X direction at the processing speed Vxd (step S1102).

[0175] Furthermore, in synchronization with the timing at which the laser irradiation position Lb reaches the end of the semiconductor substrate W on the (-X) side, the laser light source 72 is turned on, and irradiation of the laser light B from the processing head 71 to the laser irradiation position Lb is started (step S1103). As a result, the laser light B is irradiated to the laser irradiation position Lb moving along the planned division line S1 to the (+X) side in the X direction, and the planned division line S1 is processed (line processing process).

[0176] Also, in this example, the semiconductor substrate W is imaged while the laser irradiation position Lb is moving along the planned division line S1 (step S1104). Specifically, an image is captured of the imaging range Ri (i.e., the imaging range Ri of the imaging unit 8A) located on the moving side of the laser irradiation position Lb (i.e., the (+X) side) of the laser irradiation position Lb moving to the (+X) side. This allows an image to be acquired that includes an imaging point Pw (S11) on the moving side of the laser irradiation position Lb. In this way, an image showing the position of the unprocessed portion of the planned division line S1 during the line processing process can be acquired.

[0177] Then, in synchronization with the timing at which the laser irradiation position Lb reaches the end of the semiconductor substrate W on the (+X) side, the laser light source 72 is turned off, and irradiation of the laser light B from the processing head 71 to the laser irradiation position Lb ends (step S1105). Thus, during the period from steps S1103 to S1105, an image of an unprocessed portion of the planned division line S1 that is the target of the line processing is captured in parallel with the line processing being executed on the planned division line S1.

[0178] When the laser irradiation position Lb passes the planned division line S1 on the (+X) side, the laser irradiation position Lb starts to decelerate toward the (+X) side in the X direction (step S1106). In step S1107, it is confirmed whether laser processing has been completed for multiple planned division lines S parallel to the X direction. Then, if there is an unprocessed planned division line S among these planned division lines S (if "NO" in step S1107), the process returns to step S1101.

[0179] As a result, the speed Vx of the laser irradiation position Lb in the X direction, which has been decelerated toward the (+X) side in the X direction, becomes zero, and then the laser irradiation position Lb accelerates toward the (-X) side in the X direction (step S1101). Then, when the speed Vx of the laser irradiation position Lb increases to the processing speed Vxd before the laser irradiation position Lb reaches the end of the semiconductor substrate W on the (+X) side, the laser irradiation position Lb moves at a constant speed toward the (-X) side in the X direction at the processing speed Vxd (step S1102).

[0180] 18 and 19A, the inversion drive is executed in the X direction in the same manner as described above. In parallel with this inversion drive, the laser irradiation position Lb moves in the Y direction from the virtual straight line Sv1 to the virtual straight line Sv2. As a result, the laser irradiation position Lb moves in the Y direction to the virtual straight line Sv2 before the speed Vx of the laser irradiation position Lb in the X direction increases to the processing speed Vxd, and the laser irradiation position Lb reaches the planned division line S2.

[0181] However, in this example, the manner in which the laser irradiation position Lb moves in the Y direction is different from that described above. That is, in parallel with the reverse drive in which the laser irradiation position Lb decelerates, stops, and accelerates in the X direction, the laser irradiation position Lb continuously moves in the Y direction from the division line Sb1 to the division line Sb2 (continuous feed drive). In particular, the continuous feed drive of the laser irradiation position Lb in the Y direction is executed around the time when the speed Vx of the laser irradiation position Lb in the X direction becomes zero due to the reverse drive. Therefore, in this example, there is no timing when both the speed Vx in the X direction and the speed Vy in the Y direction of the laser irradiation position Lb become zero.

[0182] At the same time that the laser irradiation position Lb reaches the end of the semiconductor substrate W on the (+X) side, the laser light source 72 is turned on and the processing head 71 starts irradiating the laser light B to the laser irradiation position Lb (step S1103). As a result, the laser light B is irradiated to the laser irradiation position Lb moving along the planned division line S2 to the (-X) side in the X direction, and the planned division line S2 is processed (line processing process).

[0183] Also, in this example, the semiconductor substrate W is imaged while the laser irradiation position Lb is moving along the planned division line S2 (step S1104). Specifically, an image is captured of the imaging range Ri (i.e., the imaging range Ri of the imaging unit 8B) located on the moving side of the laser irradiation position Lb (i.e., the (-X) side) of the laser irradiation position Lb moving to the (-X) side. This allows an image to be acquired that includes an imaging point Pw (S21) on the moving side of the laser irradiation position Lb. In this way, an image showing the position of the unprocessed portion of the planned division line S2 during the line processing process can be acquired.

[0184] Then, in synchronization with the timing at which the laser irradiation position Lb reaches the end of the semiconductor substrate W on the (-X) side, the laser light source 72 is turned off, and irradiation of the laser light B from the processing head 71 to the laser irradiation position Lb ends (step S1105). Thus, during the period from steps S1103 to S1105, an image of an unprocessed portion of the planned division line S2 that is the target of the line processing is captured in parallel with the line processing being executed on the planned division line S2.

[0185] When the laser irradiation position Lb passes the planned division line S2 on the (-X) side, the laser irradiation position Lb starts to decelerate toward the (-X) side in the X direction (step S1106). In step S1107, it is confirmed whether laser processing has been completed for multiple planned division lines S parallel to the X direction. Then, if there is an unprocessed planned division line S among these planned division lines S (if "NO" in step S1107), the process returns to step S1101.

[0186] As a result, the speed Vx of the laser irradiation position Lb in the X direction, which has been decelerated toward the (-X) side in the X direction, becomes zero, and then the laser irradiation position Lb accelerates toward the (+X) side in the X direction (step S1101). Then, when the speed Vx of the laser irradiation position Lb increases to the processing speed Vxd before the laser irradiation position Lb reaches the end of the semiconductor substrate W on the (-X) side, the laser irradiation position Lb moves at a constant speed toward the (+X) side in the X direction at the processing speed Vxd (step S1102).

[0187] At this time, similarly to the above, continuous feed drive in the Y direction is executed on the laser irradiation position Lb in parallel with the reversal drive in the X direction. As a result, by the time the speed Vx of the laser irradiation position Lb in the X direction increases to the processing speed Vxd, the laser irradiation position Lb moves to the virtual straight line Sv3 in the Y direction and reaches the planned division line S3.

[0188] At the same time that the laser irradiation position Lb reaches the end of the semiconductor substrate W on the (-X) side, the laser light source 72 is turned on and the processing head 71 starts irradiating the laser light B to the laser irradiation position Lb (step S1103). As a result, the laser light B is irradiated to the laser irradiation position Lb moving along the planned division line S3 to the (+X) side in the X direction, and the planned division line S3 is processed (line processing process).

[0189] Also, in this example, the semiconductor substrate W is imaged while the laser irradiation position Lb is moving along the planned division line S3 (step S1104). Specifically, an image is captured of the imaging range Ri (i.e., the imaging range Ri of the imaging unit 8A) located on the moving side of the laser irradiation position Lb (i.e., the (+X) side) of the laser irradiation position Lb moving to the (+X) side. This allows an image to be acquired that includes an imaging point Pw (S31) on the moving side of the laser irradiation position Lb. In this way, an image showing the position of the unprocessed portion of the planned division line S3 during the line processing process can be acquired.

[0190] Then, in synchronization with the timing at which the laser irradiation position Lb reaches the end of the semiconductor substrate W on the (+X) side, the laser light source 72 is turned off, and irradiation of the laser light B from the processing head 71 to the laser irradiation position Lb ends (step S1105). Thus, during the period from steps S1103 to S1105, an image of an unprocessed portion of the planned division line S3 that is the target of the line processing is captured in parallel with the line processing being executed on the planned division line S3.

[0191] Next, the speed change of the laser irradiation position Lb will be described with reference to "speed change in X direction" and "speed change in Y direction" in Fig. 19A. In a line processing period Ts1 (steps S1103 to S1105) in which a line processing process is performed to move the laser light B to the (+X) side along the division line S1, the laser irradiation position Lb moves in the X direction at a constant processing speed Vxd but does not move in the Y direction. In addition, in a line processing period Ts2 (steps S1103 to S1105) in which a line processing process is performed to move the laser light B to the (-X) side along the division line S2, the laser irradiation position Lb moves in the X direction at a constant processing speed Vxd but does not move in the Y direction.

[0192] In addition, during a switching period Tc (steps S1106, S1101) when the line processing period Ts1 is switched to the line processing period Ts2, the following operation is executed. That is, the X-axis drive unit 65 (processing axis drive unit) decelerates the laser irradiation position Lb that has passed the planned division line S1 (first processing line) toward the (+X) side (first side) in the X direction (processing direction) toward the (+X) side, stops it (step S1106), and then accelerates it toward the (-X) side (step S1101), thereby executing a reversal drive to bring the laser irradiation position Lb to the planned division line S2 (second processing line). In parallel with this reversal drive, the Y-axis drive unit 63 (feed axis drive unit) executes a continuous feed drive that continuously moves the laser irradiation position Lb in the Y direction (feed direction) from a virtual straight line Sv1 (first virtual straight line) that extends in the X direction along the planned division line S1 to the outside of the planned division line S1 to a virtual straight line Sv2 (second virtual straight line) that extends in the X direction along the planned division line S2 to the outside of the planned division line S2.

[0193] In particular, the control unit 100 controls the X-axis drive unit 65 and the Y-axis drive unit 63 so that the Y-axis drive unit 63 starts the continuous feed drive before the X-axis drive unit 65 stops the laser irradiation position Lb in the X direction by the reversal drive, and the Y-axis drive unit 63 ends the continuous feed drive after the X-axis drive unit 65 stops the laser irradiation position Lb in the X direction by the reversal drive. In this way, the Y-axis drive unit 63 moves the laser irradiation position Lb in the Y direction before and after the movement of the laser irradiation position Lb in the X direction stops due to the reversal drive (in other words, during the period when the X-axis drive unit 65 stops the laser irradiation position Lb in the X direction by the reversal drive).

[0194] In other words, the switching period Tc includes a deceleration period Td (step S1006) in which the laser irradiation position Lb is decelerated in the X direction, and an acceleration period Ta (step S1001) in which the laser irradiation position Lb is accelerated in the X direction. Meanwhile, the Y-axis driving unit 63 continuously moves the laser irradiation position Lb in the Y direction before and after a transition period Tx in which the deceleration period Td transitions to the acceleration period Ta (i.e., moves the laser irradiation position Lb in the Y direction without stopping it). During the transition period Tx, the laser irradiation position Lb is stopped in the X direction (i.e., the speed Vx is zero).

[0195] FIG. 19B is a diagram showing a second example of the operation executed according to the flowchart of FIG. 18. FIG. 19B differs from FIG. 19A in the number of times the semiconductor substrate W is imaged in parallel with the line processing. That is, in the example of FIG. 19B, in order to execute the line processing on the planned division line S1, the imaging of the imaging range Ri (i.e., the imaging range Ri of the imaging unit 8A) located on the moving side of the laser irradiation position Lb (i.e., the (+X) side) from the laser irradiation position Lb moving to the (+X) side is executed multiple times (in this example, twice) (step S1104). As a result, two images including two imaging points Pw(S11) and Pw(S12) on the moving side of the laser irradiation position Lb from the laser irradiation position Lb are acquired. In this way, an image showing the position of the unprocessed part of the planned division line S1 during the line processing can be acquired.

[0196] Similarly, in order to execute the line processing process on the planned division line S2, the imaging of the imaging range Ri (i.e., the imaging range Ri of the imaging unit 8B) located on the moving side of the laser irradiation position Lb (i.e., the (-X) side) from the laser irradiation position Lb moving to the (-X) side is executed multiple times (in this example, twice) (step S1104). As a result, two images including two imaging points Pw (S21) and Pw (S22) on the moving side of the laser irradiation position Lb from the laser irradiation position Lb are acquired. In this way, an image showing the position of the unprocessed part of the planned division line S2 during the line processing process can be acquired. Similarly, in the line processing process on the planned division line S3, imaging is executed multiple times (step S1104).

[0197] FIG. 20 is a diagram showing an example of an image of a semiconductor substrate acquired in step S1008 of FIG. 16 or step S1104 of FIG. 18. In the above example, an image IM is acquired by capturing an image of an area including an intersection of two mutually orthogonal planned division lines S. At this time, since the image IM is acquired while the imaging range Ri moves in the X direction relative to the semiconductor substrate W, the brightness is averaged in the X direction in the image IM. As a result, a high brightness area that is high in brightness and extends parallel to the X direction corresponding to the planned division lines S, and a low brightness area that is low in brightness compared to the high brightness area and extends parallel to the X direction corresponding to the semiconductor chip C, are displayed. In particular, in the Y direction, the high brightness area is sandwiched between two low brightness areas. Therefore, the control unit 100 can confirm the position of the planned division line S in the Y direction based on the high brightness area corresponding to the planned division line S.

[0198] In the embodiment described in FIG. 18 and FIG. 19A to FIG. 19B, the Y-axis drive unit 63 executes continuous feed drive to continuously move the laser irradiation position Lb in the Y direction from on the virtual straight line Sv1 to on the virtual straight line Sv2 (steps S1106, S1101). Then, the control unit 100 controls the X-axis drive unit 65 and the Y-axis drive unit 63 so that the Y-axis drive unit 63 starts the continuous feed drive before the X-axis drive unit 65 stops the laser irradiation position Lb by the reverse drive, and the Y-axis drive unit 63 ends the continuous feed drive after the X-axis drive unit 65 stops the laser irradiation position Lb by the reverse drive. Therefore, the Y-axis drive unit 63 moves the laser irradiation position Lb in the Y direction before and after the time when the movement of the laser irradiation position Lb in the X direction stops due to the reverse drive (in other words, during the period when the X-axis drive unit 65 stops the laser irradiation position Lb by the reverse drive). That is, in the switching period Tc, both the period in which the laser irradiation position Lb is decelerated toward the (+X) side in the X direction and the period in which the laser irradiation position Lb is accelerated toward the (-X) side in the X direction are effectively utilized for moving the laser irradiation position Lb in the Y direction. As a result, it is possible to suppress the effect of the switching period Tc in which the moving direction of the laser light B is switched on the time required to complete processing of the semiconductor substrate W.

[0199] In addition, the same operation as described above is also executed during the switching period Tc from the line processing for the division line S2 to the line processing for the division line S3, and both the period during which the laser irradiation position Lb is decelerated in the X direction and the period during which it is accelerated are effectively utilized for moving the laser light B in the Y direction.

[0200] Fig. 21 is a flow chart showing an example of a method for determining laser processing conditions in line processing, Fig. 22A is a diagram showing parameters related to the determination of the laser processing conditions, Fig. 22B is a diagram showing the influence of the laser processing conditions over time, and Fig. 22C is a diagram showing an example of a table referred to in determining the laser processing conditions in Fig. 21. This table is stored in advance in the storage unit 190.

[0201] FIG. 22A shows an upper graph representing the relationship between the speed Vx at which the laser irradiation position Lb moves in the X direction and time in the line processing, and a lower graph representing the relationship between the speed Vx at which the laser irradiation position Lb moves in the X direction and the position of the laser irradiation position Lb in the X direction (i.e., the X coordinate).

[0202] As shown in the graph below, in order to execute line processing on the planned division line S, irradiation position scanning is executed in which the laser irradiation position Lb overlapping the planned division line S is irradiated with the laser light B while moving the laser irradiation position Lb in the X direction from the start point Xs on one side of the planned division line S to the end point Xe on the other side (opposite to the one side). That is, the irradiation position scanning irradiates the laser light B from the processing head 71 to the laser irradiation position Lb overlapping the planned division line S while moving the laser irradiation position Lb in the X direction from the start point Xs to the end point Xe by the X-axis drive unit 65. In this way, the above-mentioned line processing is executed in conjunction with the irradiation position scanning.

[0203] In this irradiation position scanning, a constant velocity section SC is set for the planned division line S. This constant velocity section SC is set to be located between the start point Xs and the end point Xe in the X direction and to include the planned division line S. In this example, both ends of the constant velocity section SC in the X direction coincide with both ends of the planned division line S, in other words, the constant velocity section SC coincides with the planned division line S. However, the setting manner of the constant velocity section SC is not limited to this example, and the constant velocity section SC may be set by adding an offset to the outside from both ends of the planned division line S. In this case, the constant velocity section SC becomes longer than the planned division line S. The length of the offset may be a predetermined constant value, or may be a value obtained by multiplying the length of the planned division line S by a predetermined magnification (for example, 1%). The length of such a constant velocity section SC is set according to the length of the planned division line S, and specifically, the longer the planned division line S, the longer the constant velocity section SC becomes (in other words, the shorter the planned division line S, the shorter the constant velocity section SC becomes).

[0204] In this irradiation position scanning, the laser irradiation position Lb moves in the X direction from a start point Xs on one side of the uniform speed section SC to an end point Xe on the other side of the uniform speed section SC. In addition, in an acceleration period Ta in which the laser irradiation position Lb moves from the start point Xs to one end Xss of the uniform speed section SC in the X direction, the laser irradiation position Lb accelerates in the X direction at an acceleration A, and the X-directional speed Vx of the laser irradiation position Lb increases from zero to a processing speed Vxd. In addition, in a uniform speed period Tsc (which coincides with the line processing period Ts in this example) in which the laser irradiation position Lb moves in the X direction from one end Xss of the uniform speed section SC to the other end Xse, the laser irradiation position Lb moves in the X direction at a constant processing speed Vxd. Furthermore, in the X direction, during a deceleration period Td in which the laser irradiation position Lb moves from the other end Xse of the constant velocity section SC to the end point Xe, the laser irradiation position Lb decelerates in the X direction at an acceleration A, and the X-direction speed Vx of the laser irradiation position Lb decreases from the processing speed Vxd to zero.

[0205] In this case, the acceleration period Ta is the period (Vxd / A) required for the speed Vx to increase from zero to the processing speed Vxd at the acceleration A, the constant speed period Tsc is the period (Lsc / Vxd) required to move the constant speed distance Lsc, which is the length of the constant speed section SC, at the processing speed Vxd, and the deceleration period Td is the period (Vxd / A) required for the speed Vx to decrease from the processing speed Vxd to zero at the acceleration A. Therefore, the scanning time t required to scan the irradiation position is t=2×Vxd / A+Lsc / Vxd Therefore, the relationship shown in FIG. 22B is established between the processing speed Vxd and the scanning time t. In other words, when the processing speed Vxd is Vxd_min (=(Lsc×A / 2) 1 / 2 ), the scanning time t is at its minimum. Therefore, by setting the processing speed Vxd according to the length of the constant speed section SC (constant speed distance Lsc), the line processing can be performed efficiently.

[0206] However, when the processing speed Vxd is changed, it is necessary to change the frequency of the laser light B emitted from the laser light source 72. Specifically, the faster the processing speed Vxd is, the higher the frequency of the laser light B needs to be. In contrast, the frequency of the laser light B can only be changed stepwise, not continuously. Therefore, the table of FIG. 22C is used. This table specifies the relationship between the constant speed distance Lsc (in this example, the length of the planned division line S), the processing speed Vxd, and the frequency fc of the laser light B. Specifically, when the constant speed distance Lsc is equal to or less than Lsc(1), the processing speed Vxd is set to Vxd(1), and the frequency of the laser light B is set to fc(1), and when the constant speed distance Lsc is greater than Lsc(1) and equal to or less than Lsc(2), the processing speed Vxd is set to Vxd(2), and the frequency of the laser light B is set to fc(2). These laser processing conditions are specified in the table.

[0207] That is, in the laser processing condition determination of Fig. 21, the length (constant speed distance Lsc) of the constant speed section SC set for the planned division line S to be the target of the line processing process is acquired (step S1201). Then, based on the constant speed distance Lsc acquired in step S1201 and the table of Fig. 22C, the processing speed Vxd is determined (step S1202), and the frequency fc of the laser light B is determined (step S1203). In this way, according to the laser processing conditions (processing speed Vxd and frequency fc) determined by Fig. 21, the irradiation position scanning is performed.

[0208] Incidentally, the irradiation position scanning is performed sequentially for a plurality of planned division lines S parallel to the X direction. In other words, a plurality of irradiation position scanning is performed for different planned division lines S. In contrast, the laser processing condition determination in Fig. 21 is performed for each of a plurality of irradiation position scanning, and each irradiation position scanning performs movement of the laser irradiation position Lb and irradiation of the laser light B according to the laser processing conditions determined for that irradiation position scanning.

[0209] In particular, when the semiconductor substrate W on which multiple planned division lines S parallel to the X direction are formed is circular as in the above example, the planned division lines S become shorter as they move away from the center of the circle in the Y direction, and the uniform speed distance Lsc set for the planned division lines S also becomes shorter. In other words, the uniform speed distance Lsc set in the irradiation position scanning differs depending on the position in the Y direction of the planned division lines S targeted by the irradiation position scanning. Therefore, it becomes appropriate to execute the laser processing condition determination for each of the irradiation position scannings executed in sequence for the multiple planned division lines S.

[0210] The laser processing condition determination can be performed at any timing before the start of the irradiation position scanning targeted by the laser processing condition determination. For example, before the start of a plurality of irradiation position scannings corresponding to a plurality of planned division lines S parallel to the X direction, the laser processing condition determination may be performed for all of the plurality of irradiation position scannings. Alternatively, when a next irradiation position scanning is performed following a first irradiation position scanning, the laser processing condition determination for the next irradiation position scanning may be performed during the execution of the first irradiation position scanning.

[0211] As shown in FIG. 22C, the adjustment of the machining speed Vxd is performed by selecting one from among a plurality of discrete machining speeds Vxd(1), Vxd(2), Vxd(3), and Vxd(4), and the adjustment of the oscillation frequency fc is performed by selecting one from among a plurality of discrete oscillation frequencies fc(1), Vxd(2), Vxd(3), and Vxd(4). That is, in the laser machining condition determination, the machining speed Vxd and the oscillation frequency fc are selected according to which of the plurality of (four) ranges shown in FIG. 22C the constant speed distance Lsc belongs to. In this case, when the machining speed Vxd and the oscillation frequency fc are adjusted by performing the laser machining condition determination for each of the plurality of irradiation position scans, if the range to which the constant speed distance Lsc belongs is the same between the two laser irradiation position scans that are continuously performed, the machining speed Vxd and the oscillation frequency fc are maintained. On the other hand, when the ranges to which the constant speed distance Lsc belongs differ between two successively executed laser irradiation position scans, the machining speed Vxd and the transmission frequency fc are changed (in other words, switched). That is, the adjustment of the machining speed Vxd includes maintaining the machining speed Vxd and changing (switching) the machining speed Vxd, and the adjustment of the transmission frequency fc includes maintaining the transmission frequency fc and changing (switching) the transmission frequency fc.

[0212] As described above, in the above embodiment, the laser processing apparatus 1 corresponds to an example of a “laser processing apparatus” of the present invention, the chuck stage 3 corresponds to an example of a “support member” of the present invention, the Y-axis drive unit 63 corresponds to an example of a “feed axis drive unit” of the present invention, the X-axis drive unit 65 corresponds to an example of a “processing axis drive unit” of the present invention, the processing head 71 corresponds to an example of a “processing head” of the present invention, the imaging unit 8 corresponds to an example of an “imaging unit” of the present invention, the control unit 100 corresponds to an example of a “control unit” of the present invention, the control unit 100 corresponds to an example of a “computer” of the present invention, the laser processing program 191 corresponds to an example of a “laser processing program” of the present invention, the recording medium 192 corresponds to an example of a “recording medium” of the present invention, and the laser light B corresponds to an example of a “laser light” of the present invention. The laser irradiation position Lb corresponds to an example of a "laser irradiation position" of the present invention, the position Pb2 corresponds to an example of a "pause position" of the present invention, the imaging range Ri corresponds to an example of an "imaging range" of the present invention, the planned division line S corresponds to an example of a "processing line" of the present invention, the virtual straight line Sv corresponds to an example of a "virtual straight line" of the present invention, the switching period Tc corresponds to an example of a "switching period" of the present invention, the stop period Tt corresponds to an example of a "stop period" of the present invention, the semiconductor substrate W corresponds to an example of a "processing object" of the present invention, the X direction corresponds to an example of a "processing direction" of the present invention, the Y direction corresponds to an example of a "feed direction" of the present invention, and the (+X) side and the (-X) side correspond to the "first side" and "second side" of the present invention or the "second side" and "first side" of the present invention.

[0213] The present invention is not limited to the above embodiment, and various modifications can be made to the above without departing from the spirit of the present invention. For example, in the above embodiment, the use of the captured image is not particularly described. However, such images can be used for various purposes. For example, the unprocessed planned division line S may be displaced in the Y direction due to laser processing of the planned division line S. Therefore, the control unit 100 can calculate the amount of displacement of the unprocessed planned division line S in the Y direction based on the image of the semiconductor substrate W, and align the planned division line S to be subjected to the line processing process with the laser irradiation position Lb based on the amount of displacement.

[0214] In the above example, the imaging unit 8 captures an image of the intersection of two mutually perpendicular planned division lines S, but the imaging target of the imaging unit 8 is not limited to this and may be, for example, an alignment mark attached to the semiconductor chip C.

[0215] Further, the specific configuration for moving the laser irradiation position Lb relatively to the semiconductor substrate W is not limited to the above-mentioned XYθ driving table 6, but may be, for example, a driving mechanism for driving the processing head 71 in the X and Y directions.

[0216] Furthermore, the number of imaging units 8 is not limited to two, and may be, for example, one.

[0217] Also, the semiconductor chips C may be individually separated by the above-mentioned laser processing method (substrate processing in FIG. 11, etc.) (semiconductor chip manufacturing method). In this semiconductor chip manufacturing method, a line processing process is performed on the division lines S of the semiconductor substrate W by the above-mentioned laser processing method, and a modified layer is formed (laser processing step). Next, the tape E holding the semiconductor substrate W is stretched to expand the tape E, thereby separating each of the multiple semiconductor chips C (expanding step). [Explanation of symbols]

[0218] 1...Laser processing equipment 3...Chuck stage (support member) 63...Y-axis drive unit (feed axis drive unit) 65...X-axis drive unit (machining axis drive unit) 71...Processing head 8…Imaging unit 100...Control unit (computer) 191...Laser processing program 192...Recording media

Claims

1. A support member that supports a workpiece having a plurality of processing lines parallel to each other such that the processing lines are parallel to a predetermined processing direction; A processing head that irradiates a laser beam to a predetermined laser irradiation position; a processing axis driving unit that drives at least one of the support member and the processing head in the processing direction to move the laser irradiation position relative to the workpiece in the processing direction; a feed axis drive unit that drives at least one of the support member and the processing head in a feed direction perpendicular to the processing direction to move the laser irradiation position relative to the workpiece in the feed direction; a control unit that processes the processing line by executing a line processing process in which the processing head irradiates the laser irradiation position with a laser beam from the processing head while aligning the laser irradiation position with the processing line using the feed axis drive unit, and the processing axis drive unit moves the laser irradiation position in the processing direction with respect to the workpiece; an imaging unit that images a predetermined imaging range that moves relatively to the object together with the laser irradiation position as the laser irradiation position moves relatively to the object; Equipped with The control unit sequentially executes a first line processing process for processing a first processing line among the plurality of processing lines by the line processing process moving the laser irradiation position to a first side in the processing direction, and a second line processing process for processing a second processing line among the plurality of processing lines, the second processing line being different from the first processing line, by the line processing process moving the laser irradiation position to a second side opposite to the first side in the processing direction; During a switching period from the end of the first line processing process to the start of the second line processing process, the processing axis drive unit executes a reverse drive in the processing direction to cause the laser irradiation position that has passed the first processing line to the first side to decelerate and stop toward the first side, and then accelerates toward the second side, thereby causing the laser irradiation position to reach the second processing line, and the feed axis drive unit moves the laser irradiation position in the feed direction from a first virtual straight line that is extended in the processing direction along the first processing line to the outside of the first processing line, to a second virtual straight line that is extended in the processing direction along the second processing line to the outside of the second processing line, In the processing direction, the imaging range is located on the second side of the laser irradiation position, The imaging unit images a portion of the object that overlaps with the imaging range during the switching period, The control unit causes the feed axis drive unit to stop the laser irradiation position during the switching period, overlapping with a timing at which the processing axis drive unit stops the laser irradiation position by the reverse drive, thereby providing a stop period during which the laser irradiation position stops in both the processing direction and the feed direction; The imaging unit is a laser processing device that images a portion of the object that overlaps with the imaging range during the stop period.

2. 2. The laser processing apparatus according to claim 1, wherein, during the switching period, the feed axis drive unit finishes moving the laser irradiation position from the first virtual straight line to the second virtual straight line before the processing axis drive unit stops the laser irradiation position in the reversal drive.

3. 2. The laser processing apparatus according to claim 1, wherein, during the switching period, the feed axis drive unit starts moving the laser irradiation position from the first virtual straight line to the second virtual straight line after the processing axis drive unit stops the laser irradiation position in the reversal drive.

4. the feed shaft driving unit executes movement of the laser irradiation position from the first virtual straight line to the second virtual straight line such that the laser irradiation position passes through a temporary stop position different from both the first virtual straight line and the second virtual straight line in the feed direction; 2. The laser processing apparatus according to claim 1, wherein the control unit provides the stop period by controlling the processing axis drive unit and the feed axis drive unit so that the feed axis drive unit stops the laser irradiation position at the temporary stop position at a timing overlapping with a timing at which the processing axis drive unit stops the laser irradiation position by the reverse drive.

5. 5. The laser processing device according to claim 4, wherein the temporary stop position is provided in a section between the first virtual straight line and the second virtual straight line in the feed direction.

6. 5. The laser processing device according to claim 4, wherein the temporary stop position is provided outside a section between the first virtual straight line and the second virtual straight line in the feed direction.

7. the workpiece has a plurality of subsequent processing lines each perpendicular to the plurality of processing lines, The laser processing device according to claim 1 , wherein the imaging section images a portion included in the imaging range where the processing line and the subsequent processing line intersect.

8. A support member that supports a workpiece having a plurality of parallel processing lines such that the processing lines are parallel to a predetermined processing direction; A processing head that irradiates a laser beam to a predetermined laser irradiation position; a processing axis driving unit that drives at least one of the support member and the processing head in the processing direction to move the laser irradiation position relative to the workpiece in the processing direction; a feed axis drive unit that drives at least one of the support member and the processing head in a feed direction perpendicular to the processing direction to move the laser irradiation position relative to the workpiece in the feed direction; a control unit that processes the processing line by executing a line processing process in which the processing head irradiates the laser irradiation position with a laser beam from the processing head while aligning the laser irradiation position with the processing line using the feed axis drive unit, and the processing axis drive unit moves the laser irradiation position in the processing direction with respect to the workpiece; an imaging unit that images a predetermined imaging range that moves relatively to the object together with the laser irradiation position as the laser irradiation position moves relatively to the object; Equipped with The control unit sequentially executes a first line processing process for processing a first processing line among the plurality of processing lines by the line processing process moving the laser irradiation position to a first side in the processing direction, and a second line processing process for processing a second processing line among the plurality of processing lines, the second processing line being different from the first processing line, by the line processing process moving the laser irradiation position to a second side opposite to the first side in the processing direction; During a switching period from the end of the first line processing process to the start of the second line processing process, the processing axis drive unit executes a reverse drive in the processing direction to cause the laser irradiation position that has passed the first processing line to the first side to decelerate and stop toward the first side, and then accelerates toward the second side, thereby causing the laser irradiation position to reach the second processing line, and the feed axis drive unit moves the laser irradiation position in the feed direction from a first virtual straight line that is extended in the processing direction along the first processing line to the outside of the first processing line, to a second virtual straight line that is extended in the processing direction along the second processing line to the outside of the second processing line, In the processing direction, the imaging range is located on the second side of the laser irradiation position, The imaging unit images a portion of the object that overlaps with the imaging range during the switching period, the workpiece has a plurality of subsequent processing lines each perpendicular to the plurality of processing lines, The imaging unit is a laser processing device that images a portion included in the imaging range where the processing line and the next processing line intersect.

9. A laser processing method for a workpiece having a plurality of processing lines parallel to each other, comprising: processing a first processing line among the plurality of processing lines, and then processing a second processing line different from the first processing line, the method comprising: supporting the object to be processed by a support member so that the processing line is parallel to a predetermined processing direction; a step of executing a first line processing process in which a laser beam is irradiated from the processing head to the laser irradiation position in a state where the laser irradiation position is aligned with the first processing line by a feed axis drive unit that drives at least one of the processing head and the support member in a feed direction perpendicular to the processing direction, while the laser irradiation position is moved to a first side in the processing direction relative to the workpiece by a processing axis drive unit that drives at least one of the processing head and the support member in the processing direction; a step of moving the laser irradiation position in the feed direction by the feed axis drive unit from a first virtual straight line extending in the processing direction along the first processing line to an outside of the first processing line to a second virtual straight line extending in the processing direction along the second processing line to an outside of the second processing line, while executing a reverse drive by the processing axis drive unit to bring the laser irradiation position to the second processing line by decelerating and stopping the laser irradiation position that has passed the first processing line to the first side in the processing direction, and then accelerating it toward a second side opposite to the first side, and moving the laser irradiation position in the feed direction by the feed axis drive unit from a first virtual straight line extending in the processing direction along the first processing line to an outside of the second processing line to a second virtual straight line extending in the processing direction along the second processing line to an outside of the second processing line; capturing an image of the object to be processed by an imaging unit that captures an image of a predetermined imaging range that moves relative to the object to be processed integrally with the laser irradiation position as the laser irradiation position moves relative to the object to be processed; a step of executing a second line processing process in which the laser irradiation position is aligned with the second processing line by the feed axis drive unit, and the laser irradiation position is moved toward the second side in the processing direction relative to the workpiece by the processing axis drive unit while irradiating the laser light from the processing head to the laser irradiation position in a state where the laser irradiation position is aligned with the second processing line by the feed axis drive unit; Equipped with In the processing direction, the imaging range is located on the second side of the laser irradiation position, The imaging unit images a portion of the object overlapping with the imaging range during a switching period from when the first line processing process is ended to when the second line processing process is started, During the switching period, a stop period is provided in which the laser irradiation position is stopped in both the processing direction and the feed direction by causing the feed axis drive unit to stop the laser irradiation position at a timing overlapping with a timing at which the processing axis drive unit stops the laser irradiation position by the reverse drive, The imaging unit captures an image of a portion of the object that overlaps with the imaging range during the stop period.

10. A laser processing program that causes a computer to execute the laser processing method according to claim 9.

11. A recording medium for recording the laser processing program according to claim 10 in a computer-readable manner.

12. A step of processing a semiconductor substrate on which a plurality of semiconductor chips are arranged and separated by processing lines by the laser processing method according to claim 9; a step of expanding a tape that adhesively holds the semiconductor substrate processed by the laser processing method to separate the plurality of semiconductor chips; A method for manufacturing a semiconductor chip comprising:

13. A step of processing a semiconductor substrate on which a plurality of semiconductor chips are arranged and separated by processing lines by the laser processing method according to claim 9; a step of expanding a tape that adhesively holds the semiconductor substrate processed by the laser processing method to separate the plurality of semiconductor chips; Semiconductor chips manufactured by.

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