Laser dicing device

Abstract

This laser dicing device (100) is provided with a control unit (4). When laser processing is performed on a first line along a first direction of a wafer We and then the movement in the first direction by a first moving unit (306) is turned back in the opposite direction, while a second moving unit (302, 303) is moving in a second direction, to perform laser processing on a second line along the first direction that is spaced apart from the first line in the second direction, the control unit (4) controls to adjust the timing of the start of movement of the first moving unit in the first direction during the laser processing on the second line of the wafer, on the basis of the remaining movement distance or remaining movement time of the movement of the second moving unit in the second direction after laser processing on the first line is completed.

Description

Laser dicing equipment

[0001] The present invention relates to a laser dicing device, and more particularly to a laser dicing device equipped with a laser irradiation unit that dices a wafer.

[0002] 2. Description of the Related Art A laser dicing apparatus including a laser irradiation unit for dicing a wafer is known, and is disclosed, for example, in Japanese Patent No. 5,804,716.

[0003] The above-mentioned Japanese Patent No. 5804716 discloses a laser processing apparatus (laser dicing apparatus) including a laser irradiation means (laser irradiation unit) that irradiates a wafer with a laser to dice the wafer, a holding means that holds the wafer, a moving means that moves the holding means in the processing direction and a horizontal direction perpendicular to the processing direction, and a control means that controls the movement of the holding means by the moving means. In this laser processing apparatus, the control means moves the wafer in the processing direction using the moving means to process one planned dividing line and then move the wafer in the horizontal direction perpendicular to the processing direction to move to the next planned dividing line. When moving to the next planned dividing line after processing one planned dividing line, the control means controls the movement in the horizontal direction perpendicular to the processing direction to be performed within the movement time in the processing direction, because the movement time in the processing direction is longer than the movement time in the horizontal direction perpendicular to the processing direction.

[0004] Patent No. 5804716

[0005] However, in the laser processing apparatus of Japanese Patent No. 5,804,716, when processing one division line and then moving to the next division line, if the movement time in the processing direction is longer than the movement time in the horizontal direction perpendicular to the processing direction, the horizontal movement perpendicular to the processing direction will be completed in time for the start of processing of the next division line. However, if the movement time in the processing direction is shorter than the movement time in the horizontal direction perpendicular to the processing direction, the horizontal movement perpendicular to the processing direction will not be completed in time for the start of processing of the next division line. In this case, it is difficult to perform laser processing accurately at the end of the next division line immediately after the start of processing. Therefore, when sequentially laser processing a wafer along multiple lines, it is desirable to prevent the movement time between laser processing lines from becoming too long while also preventing a decrease in laser processing accuracy at the end of each line.

[0006] This invention has been made to solve the above-mentioned problems, and one object of the invention is to provide a laser dicing device that, when performing laser processing on a wafer sequentially along multiple lines, can prevent the travel time between laser processing between multiple lines from becoming long, while also preventing a decrease in laser processing accuracy at the ends of each line.

[0007] A laser dicing device according to one aspect of the present invention includes a wafer holding unit that holds a wafer ring structure including a circular wafer, a sheet member to which the wafer is attached, and a ring frame that supports the sheet member; a laser irradiation unit that irradiates a laser onto the wafer held by the wafer holding unit to dice the wafer; a first moving unit that moves the wafer holding unit relatively to the laser irradiation unit in a first horizontal direction; a second moving unit that moves the wafer holding unit relatively to the laser irradiation unit in a second direction perpendicular to the first direction; and a laser beam irradiating unit that irradiates a laser beam onto the wafer held by the wafer holding unit. and a control unit that controls the irradiation unit to irradiate a laser and laser process the wafer along a first direction, wherein after laser processing a first line along the first direction of the wafer, the control unit controls the second moving unit to move in the second direction while reversing the movement in the first direction by the first moving unit to perform laser processing on a second line along the first direction that is spaced apart from the first line in the second direction, and adjusts the timing of the first moving unit to start moving in the first direction when laser processing the second line of the wafer after laser processing on the first line is completed, based on the remaining movement distance or remaining movement time of the second moving unit's movement in the second direction.

[0008] In the laser dicing apparatus according to one aspect of the present invention, as described above, when, after laser processing a first line on the wafer along a first direction, the second moving unit moves in the second direction while moving in the second direction, and then reverses the movement in the first direction by the first moving unit to perform laser processing on a second line along the first direction that is spaced apart from the first line in the second direction, the control unit controls the first moving unit to adjust the timing of start of movement in the first direction by the first moving unit when laser processing the second line on the wafer after laser processing on the first line is completed, based on the remaining movement distance or remaining movement time of the movement in the second direction by the second moving unit. As a result, when transitioning from laser processing on the first line to laser processing on the second line on the wafer, if the movement time in the first direction is longer than the movement time in the second direction, the movement in the first direction and the movement in the second direction are performed in parallel, thereby preventing the movement time from becoming too long before transitioning to laser processing on the second line. Furthermore, when laser processing of a wafer is shifted from a first line to a second line, if the movement time in the first direction is shorter than the movement time in the second direction, the timing of the return movement in the first direction can be adjusted to match the remaining movement distance or remaining movement time of the movement in the second direction, thereby preventing the movement in the second direction from being too late before the start of laser processing. As a result, when laser processing is performed sequentially along multiple lines on a wafer, it is possible to prevent the movement time between laser processing lines from becoming too long and to prevent a decrease in laser processing accuracy at the end of each line.

[0009] In the laser dicing apparatus according to the above aspect, preferably, the first moving unit moves the wafer holder relative to the laser irradiation unit so that, after laser processing on the first line is completed and before laser processing on the second line is started, the first moving unit decelerates, stops, and accelerates in the opposite direction to the processing speed. The control unit adjusts the timing of the start of movement in the first direction by the first moving unit when laser processing the second line of the wafer is performed based on the remaining distance or time of movement in the second direction by the second moving unit after laser processing on the first line is completed, so that the movement speed in the first direction by the first moving unit reaches the processing speed at the laser processing start position on the second line, and the movement position in the second direction by the second moving unit is located on the second line. This configuration ensures that the movement in the second direction is reliably completed at the end of the second line where laser processing starts, and that the movement speed in the first direction is reliably accelerated to the processing speed. As a result, a decrease in laser processing accuracy at the end of the second line can be effectively prevented. In the movement in the first direction, the wafer holder is moved relative to the laser irradiation unit so as to decelerate, stop, and then accelerate in the opposite direction to reach the processing speed, and stopping means that the absolute value of the speed becomes 0. In other words, the stopping time may be as short as possible (for example, the stopping time may be 0 seconds).

[0010] In the laser dicing apparatus according to the above aspect, preferably, the control unit acquires the movement position in the second direction by the second movement unit after laser processing on the first line is completed, and controls to adjust the timing of start of movement in the first direction by the first movement unit when laser processing the second line of the wafer based on the acquired movement position in the second direction. With this configuration, when transitioning from laser processing on the first line to laser processing on the second line, movement in the second direction can be monitored and movement in the first direction can be started, thereby effectively preventing movement in the first direction from reaching the laser processing start position of the second line before movement in the second direction is completed.

[0011] In the laser dicing apparatus according to the above aspect, preferably, the control unit acquires the remaining movement time in the second direction by the second movement unit after laser processing on the first line is completed, and controls to adjust the timing of start of movement in the first direction by the first movement unit when laser processing the second line of the wafer based on the acquired remaining movement time in the second direction. With this configuration, when transitioning from laser processing on the first line to laser processing on the second line, the remaining movement time in the second direction can be monitored and movement in the first direction can be started, thereby effectively preventing movement in the first direction from reaching the laser processing start position of the second line before movement in the second direction is completed.

[0012] In a laser dicing device configured such that the control unit controls to adjust the timing at which the first moving unit starts moving in the first direction when laser processing a second line on a wafer so that the movement speed in the first direction by the first moving unit becomes the processing speed at the laser processing start position on the second line and the movement position in the second direction by the second moving unit is on the second line, preferably, when the movement distance when decelerating and the movement distance when accelerating in the first direction by the first moving unit are the same, the control unit starts to decelerate the movement in the first direction by the first moving unit after laser processing on the first line is completed at a position that is outer than the wafer, or at a position further outer than the outer position, between the processing end position on the first line and the processing start position on the second line. With this configuration, by adjusting the timing of deceleration of movement in the first direction after laser processing on the first line is completed, it is possible to ensure the distance required for acceleration so that the speed in the first direction becomes the processing speed during laser processing on the second line, thereby more effectively preventing a decrease in laser processing accuracy at the end of the second line.

[0013] In a laser dicing apparatus configured such that the control unit adjusts the timing of start of movement in the first direction by the first moving unit when performing laser processing on the second line of the wafer so that the movement speed in the first direction by the first moving unit becomes the processing speed at the laser processing start position on the second line and the movement position in the second direction by the second moving unit is on the second line, preferably, when the movement time in the second direction by the second moving unit is longer than the movement time in the first direction by the first moving unit after laser processing on the first line is completed, the control unit controls the first moving unit to start movement in the first direction when performing laser processing on the second line of the wafer at a timing when the remaining movement time in the second direction by the second moving unit becomes equal to or less than the acceleration time in the first direction by the first moving unit. This configuration more effectively prevents movement in the first direction from reaching the laser processing start position of the second line before movement in the second direction is completed.

[0014] In a laser dicing apparatus configured such that the control unit adjusts the timing of the start of movement in the first direction by the first moving unit when laser processing the second line of the wafer so that the movement speed in the first direction by the first moving unit becomes the processing speed at the laser processing start position on the second line and the movement position in the second direction by the second moving unit is on the second line, preferably, if the movement time in the second direction by the second moving unit is shorter than the movement time in the first direction by the first moving unit after laser processing on the first line is completed, the control unit controls the first moving unit to start movement in the first direction when laser processing the second line of the wafer is performed immediately after the first moving unit decelerates and stops in the first direction. With this configuration, movement in the second direction can be performed during movement in the first direction, so laser processing on the second line can be started without waiting for movement in the second direction. As a result, it is possible to effectively prevent long movement times between laser processing operations between multiple lines.

[0015] In a laser dicing apparatus configured such that the control unit adjusts the timing of start of movement in the first direction by the first moving unit when laser processing a second line on the wafer so that, at the laser processing start position on the second line, the movement speed in the first direction by the first moving unit becomes the processing speed and the movement position in the second direction by the second moving unit is on the second line, preferably, when the deceleration speed and the acceleration speed in the first direction by the first moving unit are different, the control unit adjusts the timing of start of deceleration of the movement in the first direction by the first moving unit after laser processing on the first line is completed so that, at the laser processing start position on the second line, the movement speed in the first direction by the first moving unit becomes the processing speed. With this configuration, by adjusting the timing of deceleration of the movement in the first direction after laser processing on the first line is completed, it is possible to ensure a distance required for acceleration so that the speed in the first direction becomes the processing speed in laser processing on the second line, thereby more effectively suppressing a decrease in laser processing accuracy at the end of the second line.

[0016] In a laser dicing device configured such that the control unit controls to adjust the timing of start of movement in the first direction by the first moving unit when laser processing a second line on the wafer so that the movement speed in the first direction by the first moving unit becomes the processing speed at the laser processing start position on the second line and the movement position in the second direction by the second moving unit is on the second line, preferably, the control unit controls to start decelerating the movement in the first direction by the first moving unit at the processing start position on the second line after laser processing on the first line is completed if the speed at which the first moving unit decelerates and the speed at which the first moving unit accelerates are the same and if the distance in the first direction from the processing end position on the first line to where it stops is greater than the distance from where it stops to the processing start position on the second line; and to start decelerating the movement in the first direction by the first moving unit at the processing end position on the first line after laser processing on the first line is completed if the distance in the first direction from the processing end position on the first line to where it stops is equal to or less than the distance from where it stops to the processing start position on the second line. With this configuration, even if the processing end position on the first line and the processing start position on the second line differ in the first direction when laser processing a circular wafer, by adjusting the timing of deceleration of movement in the first direction after laser processing on the first line is completed, it is possible to ensure the distance required for acceleration so that the speed in the first direction becomes the processing speed during laser processing on the second line.

[0017] In the laser dicing apparatus according to the above aspect, preferably, the second moving unit moves the wafer holder relative to the laser irradiation unit in a second horizontal direction perpendicular to the first direction, and the control unit, after laser processing on the first line is completed, controls to adjust the timing of start of movement in the first direction by the first moving unit when laser processing the second line of the wafer is performed, based on the remaining movement distance or remaining movement time of the second horizontal movement by the second moving unit. With this configuration, when laser processing of the first line and the second line spaced apart in the horizontal direction is performed consecutively, it is possible to prevent the movement time between the laser processing of the first line and the second line from becoming long and to prevent a decrease in laser processing accuracy at the end of each line.

[0018] In the laser dicing apparatus according to the above aspect, preferably, the second moving unit moves the wafer holder relative to the laser irradiation unit in a second direction, which is a vertical direction perpendicular to the first direction, and the control unit adjusts the timing of the first moving unit's start of movement in the first direction when laser processing the second line of the wafer is performed based on the remaining movement distance or remaining movement time of the second moving unit in the vertical direction after laser processing of the first line is completed. With this configuration, when laser processing of the first and second lines spaced apart in the vertical direction (thickness direction of the wafer) is performed consecutively, it is possible to prevent the movement time between the laser processing of the first and second lines from becoming long and to prevent a decrease in laser processing accuracy at the ends of each line.

[0019] According to the present invention, as described above, when laser processing is performed sequentially along multiple lines on a wafer, it is possible to prevent the travel time between laser processing between multiple lines from becoming long, while also preventing a decrease in laser processing accuracy at the ends of each line.

[0020] FIG. 1 is a plan view showing a laser dicing apparatus according to an embodiment; FIG. 2 is a plan view showing a wafer to be laser diced in the laser dicing apparatus according to an embodiment; FIG. 3 is a block diagram showing a control configuration of the laser dicing apparatus according to an embodiment; FIG. 4 is a diagram for explaining movement in the X and Y directions when the laser dicing apparatus according to an embodiment moves in the Y direction to perform sequential laser processing; FIG. 5 is a diagram for explaining movement in the X and Y directions when the laser dicing apparatus according to an embodiment moves in the Z direction to perform sequential laser processing; FIG. 6 is a diagram for explaining the timing of movement in the X direction when the start position of the second line is outside the end position of the first line when the acceleration time and deceleration time in the X direction of the laser dicing apparatus according to an embodiment are equal; FIG. 7 is a diagram for explaining the timing of movement in the X direction when the end position of the first line is outside the start position of the second line when the acceleration time and deceleration time in the X direction of the laser dicing apparatus according to an embodiment are equal; FIG. 8 is a diagram for explaining the timing of movement in the X direction when the end position of the first line is outside the start position of the second line when the acceleration time and deceleration time in the X direction of the laser dicing apparatus according to an embodiment are equal; 1 is a diagram for explaining the timing of movement in the X direction when the end position of the first line is outside the start position of the second line when the acceleration time in the X direction of the laser dicing device according to an embodiment is shorter than the deceleration time; FIG. 2 is a diagram for explaining the timing of movement in the X direction when the start position of the second line is outside the end position of the first line when the acceleration time in the X direction of the laser dicing device according to an embodiment is longer than the deceleration time; FIG. 3 is a diagram for explaining the timing of movement in the X direction when the start position of the second line is outside the end position of the first line when the acceleration time in the X direction of the laser dicing device according to an embodiment is shorter than the deceleration time; and FIG. 4 is a diagram for explaining the timing of movement in the X direction when the movement time in the Y direction of the laser dicing device according to an embodiment is medium.1 is a diagram for explaining the timing of movement in the X direction when the movement time in the Y direction of the laser dicing device according to an embodiment is short; FIG. 2 is a diagram for explaining the timing of movement in the X direction when the movement time in the Y direction of the laser dicing device according to an embodiment is long; and FIG. 3 is a flowchart for explaining the laser dicing processing by the control unit of the laser processing device according to an embodiment.

[0021] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, specific embodiments of the present invention will be described with reference to the accompanying drawings.

[0022] The configuration of a laser dicing apparatus 100 according to an embodiment of the present invention will be described with reference to FIGS.

[0023] (Configuration of Laser Dicing Apparatus) As shown in FIG. 1, a laser dicing apparatus 100 is configured to perform laser dicing processing to form a modified layer inside a circular wafer We for dividing the wafer We.

[0024] The laser dicing apparatus 100 includes a cassette unit 1, a wafer transport unit 2, a dicing unit 3, and a control unit 4.

[0025] The cassette unit 1 is configured to accommodate a plurality of cassettes each containing a wafer ring structure W, each of which includes a wafer We attached to a sheet member Wt (see FIG. 2) and a ring frame Wf. As shown in FIG. 1, the wafer ring structure W includes a circular wafer We, a sheet member Wt to ​​which the wafer We is attached, and a ring frame Wf that supports the sheet member Wt. The sheet member Wt is attached to one side of the ring frame Wf. The ring frame Wf is annular. The wafer We is disposed inside the annular ring frame Wf. The wafer We is attached to the surface of the sheet member Wt facing the ring frame Wf.

[0026] The cassette unit 1 includes a plurality of cassette placement units 11 and a Z-direction movement mechanism 12 .

[0027] The multiple cassette mounting units 11 include one cassette mounting unit and another cassette mounting unit. A cassette containing a plurality of unprocessed wafers We is mounted on one cassette mounting unit. Furthermore, a cassette containing a plurality of processed wafers We is mounted on the other cassette mounting unit. The Z-direction movement mechanism 12 is configured to move the multiple cassette units 1 integrally in the Z1 direction or the Z2 direction. The Z-direction movement mechanism 12 includes, for example, a linear conveyor module or a drive unit having a ball screw and a motor with an encoder.

[0028] The wafer transport unit 2 is configured to transport the wafer ring structure W between the cassette unit 1 and the dicing unit 3. Specifically, the wafer transport unit 2 has a clamp hand unit 21, a Y-direction movement mechanism 22, rail units 23 and 24, a transfer head unit 25, a transfer head unit 26, and a Z-direction movement mechanism 27.

[0029] The clamp hand unit 21 is configured to clamp the ring frame Wf of the wafer ring structure W and remove it from the cassette unit 1 or store it in the cassette unit 1. The clamp hand unit 21 is moved in each of the Y1 direction and the Y2 direction by a Y-direction movement mechanism 22. The Y-direction movement mechanism 22 has, for example, a linear conveyor module or a drive unit having a ball screw and a motor with an encoder.

[0030] The clamp hand unit 21 transports the wafer ring structure W removed from the cassette unit 1 to the rail unit 23 using the Y-direction movement mechanism 22. The clamp hand unit 21 transports the wafer ring structure W removed from the cassette unit 1 to the rail unit 24 using the Y-direction movement mechanism 22. The clamp hand unit 21 stores the processed wafer ring structure W placed on the rail unit 24 into the cassette unit 1 using the Y-direction movement mechanism 22.

[0031] Rail portion 23 is configured to support, from the Z2 direction, the wafer ring structure W placed by clamp hand portion 21. Rail portion 24 is configured to support, from the Z2 direction, the wafer ring structure W placed by clamp hand portion 21. Rail portion 23 and rail portion 24 are arranged side by side in this order from the Y2 direction side toward the Y1 direction side.

[0032] Each of the transfer and placement head units 25 and 26 is configured to adsorb the ring frame Wf of the wafer ring structure W. Each of the transfer and placement head units 25 and 26 is provided with an adsorption unit having a suction hole or the like for adsorbing the ring frame Wf of the wafer ring structure W. The Z-direction movement mechanism 27 is configured to independently move each of the transfer and placement head units 25 and 26 in the Z1 direction or the Z2 direction. The Z-direction movement mechanism 27 includes, for example, a linear conveyor module or a drive unit having a ball screw and a motor with an encoder.

[0033] As shown in FIG. 1 , the dicing unit 3 includes a laser irradiation unit 301, a Z-direction moving unit 302, a Y-direction moving unit 303, a distance measurement sensor 304, an X-direction moving unit 306, a chuck table unit 307, a low-magnification imaging unit 308, a high-magnification imaging unit 309, a Z-direction moving mechanism 310, and a frame 311. The Z-direction moving unit 302 is an example of a "second moving unit" in the claims. The Y-direction moving unit 303 is an example of a "second moving unit" in the claims. The X-direction moving unit 306 is an example of a "first moving unit" in the claims. The chuck table unit 307 is an example of a "wafer holding unit" in the claims.

[0034] The laser irradiation unit 301 is configured to process the wafer We by irradiating a laser beam toward an irradiation position. The laser irradiation unit 301 dices the wafer We by irradiating the wafer We held on the chuck table unit 307 with a laser. That is, the laser irradiation unit 301 is configured to form a modified layer inside the wafer We by irradiating the wafer We, on which a plurality of semiconductor chips Ch (see FIG. 2) are provided, with a laser beam.

[0035] The laser irradiation unit 301 is configured to irradiate the wafer We with a laser along each of a plurality of streets Ws (see FIG. 2 ) on the wafer We while moving the wafer We relative to the laser irradiation unit 301 using a chuck table 307. The laser irradiation unit 301 is attached to a frame 311 via a Z-direction moving unit 302. The laser irradiation unit 301 is movable in the Z1 and Z2 directions by the Z-direction moving unit 302, but its horizontal position is fixed. The Z-direction moving unit 302 has, for example, a linear conveyor module or a drive unit having a ball screw and a motor with an encoder. A processing line to be processed by the laser is set along each of the plurality of streets Ws.

[0036] The Z-direction moving unit 302 moves the chuck table unit 307 relative to the laser irradiation unit 301 in a second direction (Z direction) that is vertically perpendicular to the first direction (X direction). Specifically, the Z-direction moving unit 302 moves the laser irradiation unit 301 in the vertical direction (Z direction). This makes it possible to change the focal height position of the laser light irradiated by the laser irradiation unit 301. In other words, it is possible to change the laser processing position in the thickness direction of the wafer We.

[0037] 1 , the Y-direction moving unit 303 is configured to move the X-direction moving unit 306 and the chuck table unit 307 in the Y1 direction and the Y2 direction, respectively. The Y-direction moving unit 303 is attached to the base 5. The Y-direction moving unit 303 has a drive unit 331, a first guide rail 332, and a second guide rail 333.

[0038] The Y-direction moving unit 303 moves the chuck table unit 307 relative to the laser irradiation unit 301 in a second horizontal direction (Y direction) perpendicular to the first direction (X direction). Specifically, the Y-direction moving unit 303 moves the chuck table unit 307 in the Y direction. This makes it possible to change the processing line formed by the laser light irradiated by the laser irradiation unit 301 in the horizontal Y direction.

[0039] The drive unit 331 is a drive unit that generates a drive force that moves the X-direction movement unit 306 in the Y1 direction and the Y2 direction. The drive unit 331 has, for example, a linear conveyor module or a motor with a ball screw and an encoder.

[0040] The first guide rail 332 and the second guide rail 333 each extend along the Y direction so as to guide movement of the X-direction moving unit 306 in the Y direction. The first guide rail 332 and the second guide rail 333 are arranged in X direction so as to sandwich the single drive unit 331. When viewed from the Z1 direction side, the first guide rail 332 and the second guide rail 333 are arranged symmetrically with respect to a line extending in the Y direction that passes through the center of the X-direction moving unit 306 in the X direction.

[0041] The first guide rail 332 is disposed on the X1 direction side of the single drive unit 331. The end portion of the X1 direction side of the X-direction moving unit 306 is attached to the first guide rail 332 so as to be movable in the Y direction. The second guide rail 333 is disposed on the X2 direction side of the single drive unit 331. The end portion of the X2 direction side of the X-direction moving unit 306 is attached to the second guide rail 333 so as to be movable in the Y direction.

[0042] The distance measurement sensor 304 measures the distance from the laser irradiation unit 301 to the wafer We held on the chuck table unit 307. The distance measurement sensor 304 measures the distance to the measurement object by emitting laser light and receiving the laser light reflected by the measurement object. The distance measurement sensor 304 is attached to a frame 311 to which the laser irradiation unit 301 is attached. The distance measurement sensor 304 is attached near the laser irradiation unit 301.

[0043] 1, the X-direction moving unit 306 is configured to move the chuck table unit 307 in each of the X1 and X2 directions. The X-direction moving unit 306 has, for example, a linear conveyor module or a drive unit having a ball screw and a motor with an encoder.

[0044] The X-direction moving section 306 is attached to the Y-direction moving section 303. As a result, the X-direction moving section 306 is moved in the Y1 direction and the Y2 direction by the Y-direction moving section 303.

[0045] The X-direction moving unit 306 moves the chuck table unit 307 in a horizontal first direction (X-direction) relative to the laser irradiation unit 301. Specifically, the X-direction moving unit 306 moves the chuck table unit 307 in the X-direction. This moves the wafer We along the processing line relative to the laser irradiation unit 301.

[0046] After laser processing on the first line is completed and before laser processing on the second line is started, the X-direction moving unit 306 moves the chuck table unit 307 relative to the laser irradiation unit 301 so that, during movement in the first direction (X direction), the chuck table unit 307 decelerates, stops, and then accelerates in the opposite direction to reach the processing speed. In other words, after laser processing on the first line is completed and before laser processing on the second line is started, the X-direction moving unit 306 moves the chuck table unit 307 relative to the laser irradiation unit 301 so that, during movement in the first direction (X direction), the chuck table unit 307 decreases its speed (for example, acceleration is a negative value) until the speed becomes zero, and then increases its speed in the opposite direction (for example, acceleration is the same negative value as during deceleration) until the speed becomes the processing speed. Therefore, the time during which the chuck table unit 307 is stopped (the speed becomes zero) may be infinitesimally short (for example, 0 seconds).

[0047] The chuck table 307 holds the wafer ring structure W. Specifically, the chuck table 307 is configured to hold the wafer We attached to the sheet member Wt by suction. The chuck table 307 is configured to rotate about a rotation axis along the vertical direction. This allows the chuck table 307 to rotate while holding the ring frame Wf. The chuck table 307 is also configured to be movable in the horizontal direction by the Y-direction moving unit 303 and the X-direction moving unit 306.

[0048] The low-magnification imaging unit 308 and the high-magnification imaging unit 309 are each configured to capture an image of the wafer We held on the chuck table unit 307. The low-magnification imaging unit 308 and the high-magnification imaging unit 309 are each a near-infrared imaging camera. The low-magnification imaging unit 308 and the high-magnification imaging unit 309 are each attached to a frame 311 via a Z-direction movement mechanism 310. The Z-direction movement mechanism 310 is configured to move the low-magnification imaging unit 308 and the high-magnification imaging unit 309 integrally in each of the Z1 direction and the Z2 direction. The Z-direction movement mechanism 310 includes, for example, a linear conveyor module or a drive unit having a ball screw and a motor with an encoder.

[0049] The high-magnification imaging unit 309 captures an image of an alignment mark (not shown) provided on the wafer We in order to align the wafer We. Then, based on the image capture result of the alignment mark, the position of the chuck table unit 307 in the X and Y directions is adjusted.

[0050] 3, the control unit 4 is configured to control each of the cassette unit 1, wafer transport unit 2, and dicing unit 3 to process the wafer We in the laser dicing apparatus 100. The control unit 4 is electrically connected to each of the cassette unit 1, wafer transport unit 2, laser irradiation unit 301, Z-direction movement unit 302, Y-direction movement unit 303, distance measurement sensor 304, X-direction movement unit 306, chuck table unit 307, low-magnification imaging unit 308, high-magnification imaging unit 309, and Z-direction movement mechanism 310.

[0051] Specifically, the control unit 4 includes a CPU (Central Processing Unit) 41 and a memory 42 having a ROM (Read Only Memory) and a RAM (Random Access Memory). The control unit 4 also includes a storage unit 43. The storage unit 43 stores a control program for the laser dicing apparatus 100, including the processing of the wafer We by laser. The storage unit 43 also stores processing condition data 431, which sets conditions for processing the wafer We.

[0052] The processing condition data 431 includes various conditions (settings) for processing the wafer We. For example, the processing condition data 431 includes information on conditions such as the orientation of the wafer We during processing, the position of the street on the wafer We to be processed (processing position), the depth position of the wafer We to be processed (height position from the surface), the intensity of the laser used for processing, and the movement speed during processing.

[0053] In addition, the control unit 4 controls the X-direction moving unit 306 to move the chuck table unit 307 in the first direction (X direction) relative to the laser irradiation unit 301, and controls the laser irradiation unit 301 to irradiate a laser to laser process the wafer We along the first direction (X direction).

[0054] In this embodiment, after laser processing a first line along a first direction (X direction) on the wafer We, the control unit 4 performs control to adjust the timing of start of movement in the first direction (X direction) by the X-direction movement unit 306 when performing laser processing on a second line along the first direction (X direction) spaced apart from the first line in the second direction (Y direction or Z direction) by moving in a second direction (Y direction or Z direction) by the Y-direction movement unit 303 or the Z-direction movement unit 302 while reversing the movement in the first direction (X direction) by the X-direction movement unit 306 in the opposite direction, based on the remaining movement distance or remaining movement time of the movement in the second direction (Y direction or Z direction) by the Y-direction movement unit 303 or the Z-direction movement unit 302 after laser processing on the first line is completed.

[0055] 4, after laser processing of the first line is completed, the control unit 4 controls to adjust the timing at which the X-direction movement unit 306 starts moving in the first direction (X direction) when laser processing of the second line of the wafer We, based on the remaining movement distance or remaining movement time of the horizontal second direction (Y direction) movement by the Y-direction movement unit 303. Also, as shown in FIG. 5, after laser processing of the first line is completed, the control unit 4 controls to adjust the timing at which the X-direction movement unit 306 starts moving in the first direction (X direction) when laser processing of the second line of the wafer We, based on the remaining movement distance or remaining movement time of the vertical second direction (Z direction) movement by the Z-direction movement unit 302.

[0056] In addition, the control unit 4 controls to adjust the timing of the start of movement in the first direction (X direction) by the X-direction moving unit 306 when performing laser processing on the second line of the wafer We, based on the remaining movement distance or remaining movement time of movement in the second direction (Y direction or Z direction) by the Y-direction moving unit 303 or the Z-direction moving unit 302 after laser processing on the first line is completed, so that at the laser processing start position on the second line, the movement speed in the first direction (X direction) by the X-direction moving unit 306 becomes the processing speed, and the movement position in the second direction (Y direction or Z direction) by the Y-direction moving unit 303 or the Z-direction moving unit 302 becomes on the second line.

[0057] Furthermore, when the distance traveled when decelerating and the distance traveled when accelerating are the same in the movement in the first direction (X direction) by the X-direction moving unit 306, the control unit 4 starts decelerating the movement in the first direction (X direction) by the X-direction moving unit 306 after laser processing on the first line is completed at a position that is outer than the wafer We between the processing end position on the first line and the processing start position on the second line, or at a position that is even outer than the position that is outer than the wafer We.

[0058] 6 and 7, the timing of starting movement when turning back in the X direction is adjusted so that the movement speed in the X direction becomes the processing speed (constant speed) until the X direction reaches the processing start position on the second line. As shown in Figures 6 and 7, outside the processing line, the time spent moving at a constant speed in the X direction is defined as constant speed time Tx1, the time spent moving in the deceleration section in the X direction as deceleration time Tx2, and the time spent moving in the acceleration section in the X direction as acceleration time Tx3. Note that the constant speed time Tx1 can be 0.

[0059] Furthermore, when the speed at which the X-direction moving unit 306 decelerates and the speed at which the X-direction moving unit 306 accelerates are the same in the first direction (X direction), and when the distance in the first direction (X direction) from the processing end position on the first line to the stop is greater than the distance from the stop to the processing start position on the second line, the control unit 4 controls to start decelerating the movement in the first direction (X direction) by the X-direction moving unit 306 at the processing start position on the second line after laser processing on the first line is completed, and when the distance in the first direction (X direction) from the processing end position on the first line to the stop is equal to or less than the distance from the stop to the processing start position on the second line, the control unit 4 controls to start decelerating the movement in the first direction (X direction) by the X-direction moving unit 306 at the processing end position on the first line after laser processing on the first line is completed.

[0060] As shown in Figure 6, when the acceleration time Tx3 and deceleration time Tx2 in the X direction are equal and the start position of the second line is outside the end position of the first line, the speed is constant until it reaches the processing start position of the second line in the X direction, then it decelerates from the processing start position of the second line, stops, turns around and starts moving in the X direction toward the second line.

[0061] Also, as shown in Figure 7, when the acceleration time Tx3 and deceleration time Tx2 in the X direction are equal and the end position of the first line is outside the start position of the second line, the machine decelerates and stops immediately after processing of the first line is completed, turns around, and starts moving in the X direction toward the second line.

[0062] Furthermore, after laser processing on the first line is completed, the control unit 4 acquires the movement position in the second direction (Y direction or Z direction) by the Y-direction movement unit 303 or the Z-direction movement unit 302, and, based on the acquired movement position in the second direction (Y direction or Z direction), performs control to adjust the timing at which the X-direction movement unit 306 starts movement in the first direction (X direction) when performing laser processing on the second line of the wafer We. In other words, while monitoring the movement position in the Y direction, the control unit 4 starts movement in the first direction (X direction) by the X-direction movement unit 306 when performing laser processing on the second line when the remaining movement distance in the Y direction becomes shorter than a predetermined length.

[0063] Furthermore, after laser processing on the first line is completed, the control unit 4 acquires the remaining movement time in the second direction (Y direction or Z direction) by the Y-direction movement unit 303 or the Z-direction movement unit 302, and controls the X-direction movement unit 306 to adjust the timing of starting movement in the first direction (X direction) when performing laser processing on the second line of the wafer We based on the acquired remaining movement time in the second direction (Y direction or Z direction). That is, the control unit 4 monitors the remaining movement time in the Y direction and starts movement in the first direction (X direction) by the X-direction movement unit 306 when performing laser processing on the second line when the remaining movement time in the Y direction becomes shorter than a predetermined length. Note that the timing of starting movement in the first direction (X direction) by the X-direction movement unit 306 may be adjusted taking into account both the remaining movement time and the remaining movement distance, or the timing of starting movement in the first direction (X direction) by the X-direction movement unit 306 may be adjusted taking into account either the remaining movement time or the remaining movement distance.

[0064] Furthermore, when the speed at which the X-direction moving unit 306 decelerates and the speed at which it accelerates differ during movement in the first direction (X direction) by the X-direction moving unit 306, the control unit 4 controls to adjust the timing at which the X-direction moving unit 306 starts to decelerate its movement in the first direction (X direction) after laser processing on the first line is completed so that the movement speed in the first direction (X direction) by the X-direction moving unit 306 becomes the processing speed at the laser processing start position on the second line.

[0065] For example, as shown in Figure 8, if the acceleration time Tx3 in the X direction is longer than the deceleration time Tx2 and the end position of the first line is outside the start position of the second line, when the remaining movement time Ty1 in the Y direction becomes Tx1 + Tx3 or less, the robot will turn back in the X direction and start moving toward the second line.

[0066] Also, as shown in Figure 9, if the acceleration time Tx3 in the X direction is shorter than the deceleration time Tx2 and the end position of the first line is outside the start position of the second line, when the remaining movement time Ty1 in the Y direction becomes Tx3 or less, the robot turns back in the X direction and starts moving toward the second line.

[0067] Also, as shown in Figure 10, if the acceleration time Tx3 in the X direction is longer than the deceleration time Tx2 and the start position of the second line is outside the end position of the first line, at the time when the remaining movement time Ty1 in the Y direction becomes Tx1 + Tx3 or less, the robot turns back in the X direction and starts moving toward the second line.

[0068] Also, as shown in Figure 11, if the acceleration time Tx3 in the X direction is shorter than the deceleration time Tx2 and the start position of the second line is outside the end position of the first line, at the time when the remaining movement time Ty1 in the Y direction becomes Tx3 or less, the robot turns back in the X direction and starts moving toward the second line.

[0069] 12 and 13, after laser processing on the first line is completed, if the movement time in the second direction (Y direction or Z direction) by the Y-direction moving unit 303 or the Z-direction moving unit 302 is shorter than the movement time in the first direction (X direction) by the X-direction moving unit 306, the control unit 4 controls the X-direction moving unit 306 to decelerate and stop in the movement in the first direction (X direction) and then immediately start movement in the first direction (X direction) by the X-direction moving unit 306 when performing laser processing on the second line of the wafer We.

[0070] Furthermore, as shown in FIG. 14 , after laser processing on the first line is completed, if the movement time in the second direction (Y direction or Z direction) by the Y-direction moving unit 303 or the Z-direction moving unit 302 is longer than the movement time in the first direction (X direction) by the X-direction moving unit 306, the control unit 4 controls the X-direction moving unit 306 to start movement in the first direction (X direction) when performing laser processing on the second line of the wafer We at the time when the remaining movement time in the second direction (Y direction or Z direction) by the Y-direction moving unit 303 or the Z-direction moving unit 302 becomes less than or equal to the acceleration time in the first direction (X direction) by the X-direction moving unit 306.

[0071] (Laser Dicing Processing) The laser dicing processing performed by the control unit 4 will be described with reference to FIG.

[0072] In step S1 of FIG. 15, i = 0, j = 0. Note that i is a sequential number starting from 1 corresponding to each of the multiple processing lines lined up in the Y direction. Also, j is a sequential number starting from 1 corresponding to each of the multiple processing lines lined up in the Z direction. In step S2, i = i + 1. In step S3, it is determined whether processing line i exists. That is, it is determined whether processing line i exists in the processing condition data 431 among the lines to be processed. If processing line i exists, the process proceeds to step S4; if processing line i does not exist, the laser dicing processing ends.

[0073] In step S4, j = j + 1 is set. In step S5, it is determined whether or not a processing layer j exists. That is, it is determined whether or not the processing condition data 431 includes a processing plan for processing layer j on the line to be processed. If processing layer j exists, the process proceeds to step S6, and if processing layer j does not exist, the process returns to step S2. In step S6, it is determined whether or not laser processing is in progress on the previous processing line. The process of step S6 is repeated until laser processing on the previous processing line is completed.

[0074] In step S7, the Y-direction moving unit 303 moves the wafer We in the Y direction, so that the wafer We is positioned at the position of processing line i relative to the laser irradiation unit 301. In addition, the Z-direction moving unit 302 moves the laser irradiation unit 301 in the Z direction, so that the wafer We is positioned at the position of processing layer j relative to the laser irradiation unit 301.

[0075] In step S8, it is determined whether the remaining time of movement in the Z direction is enough to start movement in the X direction. That is, at the start position of the next processing line, it is determined whether the Z direction has reached the position of the processing line at the time when the X direction has reached the processing line. The processing of step S8 is repeated until the remaining time of movement in the Z direction reaches the time to start movement in the X direction.

[0076] In step S9, it is determined whether the remaining time of movement in the Y direction is enough to start movement in the X direction. That is, at the start position of the next processing line, it is determined whether the Y direction has reached the position of the processing line at the time when the X direction has reached the processing line. The processing of step S9 is repeated until the remaining time of movement in the Y direction reaches the time to start movement in the X direction.

[0077] In step S10, movement in the X direction toward the next processing line is started. In step S11, it is determined whether the position in the X direction has reached the processing line. The determination in step S11 is repeated until the position in the X direction has reached the processing line.

[0078] When the position in the X direction reaches the processing start position of the processing line, in step S12, a laser is irradiated from the laser irradiation unit 301, and laser processing is started. In step S11, it is determined whether the position in the X direction has reached the processing line. The determination in step S11 is repeated until the position in the X direction reaches the processing line.

[0079] When the position in the X direction reaches the processing end position of the processing line, in step S14, the laser irradiation unit 301 stops emitting the laser, and the laser processing ends. Thereafter, the process returns to step S4.

[0080] (Effects of this embodiment) In this embodiment, the following effects can be obtained.

[0081] In this embodiment, as described above, after laser processing a first line along a first direction (X direction) of the wafer We, the control unit 4 moves in a second direction (Y direction or Z direction) using the Y direction movement unit 303 or the Z direction movement unit 302, while reversing the movement in the first direction by the X direction movement unit 306 in the opposite direction to perform laser processing on a second line along the first direction that is spaced apart from the first line in the second direction. After laser processing on the first line is completed, the control unit 4 controls to adjust the timing of the start of movement in the first direction by the X direction movement unit 306 when performing laser processing on the second line of the wafer We, based on the remaining movement distance or remaining movement time of the movement in the second direction by the Y direction movement unit 303 or the Z direction movement unit 302. As a result, when laser processing on a wafer We is transitioned from a first line to a second line, if the movement time in the first direction is longer than the movement time in the second direction, the movement in the first direction and the movement in the second direction are performed in parallel, thereby preventing the movement time until the transition to laser processing on the second line from becoming too long. Furthermore, when laser processing on a wafer We is transitioned from a first line to a second line, if the movement time in the first direction is shorter than the movement time in the second direction, the timing of the return movement in the first direction can be synchronized with the remaining movement distance or remaining movement time of the movement in the second direction, thereby preventing the movement in the second direction from being too late before the start of laser processing. As a result, when laser processing is performed sequentially along multiple lines on a wafer We, the movement time between laser processing lines is prevented from becoming too long, while preventing a decrease in laser processing accuracy at the end of each line.

[0082] Furthermore, in this embodiment, as described above, after laser processing on the first line is completed and before laser processing on the second line is started, the X-direction moving unit 306 moves the chuck table unit 307 relative to the laser irradiation unit 301 so that, in its movement in the first direction (X direction), it decelerates, stops, and then accelerates in the opposite direction to reach the processing speed; and the control unit 4 controls to adjust the timing of the start of movement in the first direction by the X-direction moving unit 306 when performing laser processing on the second line of the wafer We, based on the remaining movement distance or remaining movement time of the movement in the second direction by the Y-direction moving unit 303 or the Z-direction moving unit 302 after laser processing on the first line is completed, so that, at the laser processing start position on the second line, the movement speed in the first direction by the X-direction moving unit 306 reaches the processing speed, and the movement position in the second direction (Y direction or Z direction) by the Y-direction moving unit 303 or the Z-direction moving unit 302 is on the second line. This ensures that the movement in the second direction is completed at the end of the second line where laser processing begins, and that the movement speed in the first direction is accelerated to the processing speed, thereby effectively preventing a decrease in laser processing accuracy at the end of the second line.

[0083] Furthermore, in this embodiment, as described above, after laser processing on the first line is completed, the control unit 4 acquires the movement position in the second direction (Y direction or Z direction) by the Y-direction movement unit 303 or the Z-direction movement unit 302, and, based on the acquired movement position in the second direction, performs control to adjust the timing of the start of movement in the first direction (X direction) by the X-direction movement unit 306 when laser processing the second line on the wafer We. This makes it possible to monitor the movement in the second direction and start the movement in the first direction when transitioning from laser processing on the first line to laser processing on the second line, thereby effectively preventing the movement in the first direction from reaching the laser processing start position of the second line before the movement in the second direction is completed.

[0084] Furthermore, in this embodiment, as described above, after laser processing on the first line is completed, the control unit 4 acquires the remaining movement time in the second direction (Y direction or Z direction) by the Y-direction movement unit 303 or the Z-direction movement unit 302, and performs control to adjust the timing of start of movement in the first direction (X direction) by the X-direction movement unit 306 when performing laser processing on the second line of the wafer We, based on the acquired remaining movement time in the second direction. This makes it possible to monitor the remaining movement time in the second direction and start movement in the first direction when transitioning from laser processing on the first line to laser processing on the second line, thereby effectively preventing movement in the first direction from reaching the laser processing start position of the second line before movement in the second direction is completed.

[0085] Furthermore, in the present embodiment, as described above, when the movement distance during deceleration and the movement distance during acceleration in the movement in the first direction (X direction) by the X-direction movement unit 306 are the same, the control unit 4 starts deceleration of the movement in the first direction by the X-direction movement unit 306 after laser processing on the first line is completed at a position that is outer with respect to the wafer We, or a position that is further outer than the outer position with respect to the wafer We, between the processing end position of the first line and the processing start position of the second line. As a result, by adjusting the timing of deceleration of the movement in the first direction after laser processing on the first line is completed, it is possible to ensure a distance required for acceleration so that the speed in the first direction becomes the processing speed in laser processing on the second line, and therefore it is possible to more effectively suppress a decrease in laser processing accuracy at the end of the second line.

[0086] Furthermore, in this embodiment, as described above, after laser processing on the first line is completed, if the movement time in the second direction (Y direction or Z direction) by the Y-direction movement unit 303 or the Z-direction movement unit 302 is longer than the movement time in the first direction (X direction) by the X-direction movement unit 306, the control unit 4 controls the X-direction movement unit 306 to start movement in the first direction when laser processing the second line of the wafer We at the timing when the remaining movement time in the second direction by the Y-direction movement unit 303 or the Z-direction movement unit 302 becomes equal to or less than the acceleration time in the first direction by the X-direction movement unit 306. This makes it possible to more effectively prevent the movement in the first direction from reaching the laser processing start position of the second line before the movement in the second direction is completed.

[0087] Furthermore, in this embodiment, as described above, if the movement time in the second direction (Y direction or Z direction) by the Y-direction movement unit 303 or the Z-direction movement unit 302 after laser processing on the first line is shorter than the movement time in the first direction (X direction) by the X-direction movement unit 306, the control unit 4 controls the X-direction movement unit 306 to start movement in the first direction when laser processing the second line of the wafer We as soon as the movement in the first direction by the X-direction movement unit 306 decelerates and stops. This allows movement in the second direction to be performed during movement in the first direction, so laser processing on the second line can be started without waiting for movement in the second direction. As a result, it is possible to effectively prevent the movement time between laser processing on multiple lines from becoming long.

[0088] Furthermore, in the present embodiment, as described above, when the deceleration speed and the acceleration speed differ during movement in the first direction (X direction) by the X-direction movement unit 306, the control unit 4 performs control to adjust the timing at which the X-direction movement unit 306 starts to decelerate the movement in the first direction after laser processing on the first line is completed, so that the movement speed in the first direction by the X-direction movement unit 306 becomes the processing speed at the laser processing start position on the second line. In this way, by adjusting the timing at which the first direction movement is decelerated after laser processing on the first line is completed, it is possible to ensure a distance required for acceleration so that the speed in the first direction becomes the processing speed during laser processing on the second line, and therefore it is possible to more effectively suppress a decrease in laser processing accuracy at the end of the second line.

[0089] Furthermore, in this embodiment, as described above, when the speed at which the X-direction moving unit 306 decelerates and the speed at which it accelerates are the same in the movement in the first direction (X direction) by the X-direction moving unit 306, if the distance in the first direction from the processing end position on the first line to the stop is greater than the distance from the stop to the processing start position on the second line, the control unit 4 controls so that after laser processing on the first line is completed, the X-direction moving unit 306 starts decelerating the movement in the first direction at the processing start position on the second line; and if the distance in the first direction from the processing end position on the first line to the stop is equal to or less than the distance from the stop to the processing start position on the second line, the control unit 4 controls so that after laser processing on the first line is completed, the X-direction moving unit 306 starts decelerating the movement in the first direction at the processing end position on the first line. As a result, when laser processing a circular wafer We, even if the processing end position on the first line and the processing start position on the second line are different in the first direction, by adjusting the timing of deceleration of movement in the first direction after laser processing on the first line is completed, it is possible to ensure the distance required for acceleration so that the speed in the first direction becomes the processing speed in laser processing on the second line.

[0090] Furthermore, in this embodiment, as described above, the Y-direction moving unit 303 moves the chuck table unit 307 relative to the laser irradiation unit 301 in a second horizontal direction (Y direction) perpendicular to the first direction (X direction), and the control unit 4 controls, after laser processing of the first line is completed, to adjust the timing of start of movement in the first direction by the X-direction moving unit 306 when laser processing a second line on the wafer We, based on the remaining movement distance or remaining movement time of the horizontal second direction movement by the Y-direction moving unit 303. This makes it possible, when laser processing a first line and a second line spaced apart in the horizontal direction is successively performed, to prevent the movement time between laser processing of the first line and the second line from becoming long and to prevent a decrease in laser processing accuracy at the end of each line.

[0091] Furthermore, in this embodiment, as described above, the Z-direction moving unit 302 moves the chuck table unit 307 relative to the laser irradiation unit 301 in a second direction (Z direction) that is vertically perpendicular to the first direction (X direction), and the control unit 4 controls, after laser processing of the first line is completed, to adjust the timing of start of movement in the first direction by the X-direction moving unit 306 when laser processing the second line on the wafer We, based on the remaining movement distance or remaining movement time of the second vertical movement by the Z-direction moving unit 302. This makes it possible, when laser processing of a first line and a second line that are spaced apart in the vertical direction (thickness direction of the wafer We) is successively performed, to prevent a decrease in laser processing accuracy at the end of each line while preventing a lengthy movement time between the laser processing of the first line and the second line.

[0092] (Modifications) The embodiments disclosed herein should be considered to be illustrative in all respects and not restrictive. The scope of the present invention is defined by the claims, not by the description of the above-mentioned embodiments, and includes all modifications (modifications) within the meaning and scope of the claims.

[0093] For example, in the above embodiment, an example of a configuration in which the X-direction moving unit (first moving unit) moves the chuck table (wafer holding unit) in the X direction (first direction) has been shown, but the present invention is not limited to this. In the present invention, the first moving unit may move the laser irradiation unit in the first direction, or the first moving unit may move both the wafer holding unit and the laser irradiation unit in the first direction.

[0094] In the above embodiment, an example of a configuration in which the Y-direction moving unit (second moving unit) moves the chuck table (wafer holding unit) in the Y direction (second direction) has been shown, but the present invention is not limited to this. In the present invention, the second moving unit may move the laser irradiation unit in the horizontal second direction, or the second moving unit may move both the wafer holding unit and the laser irradiation unit in the horizontal second direction.

[0095] In the above embodiment, an example of a configuration in which the Z-direction moving unit (second moving unit) moves the laser irradiation unit in the vertical Z direction (second direction) has been shown, but the present invention is not limited to this. In the present invention, the second moving unit may move the wafer holding unit in the vertical second direction, or the second moving unit may move both the wafer holding unit and the laser irradiation unit in the vertical second direction.

[0096] In the above embodiment, an example of a configuration in which two transfer head units for transferring the wafer ring structure are provided is shown, but the present invention is not limited to this. In the present invention, one transfer head unit for transferring the wafer ring structure may be provided, or three or more transfer head units may be provided.

[0097] In the above embodiment, the laser irradiation unit is fixed in position in the horizontal direction, but the present invention is not limited to this. In the present invention, the laser irradiation unit may be movable in the horizontal direction.

[0098] In the above embodiment, for convenience of explanation, the control processing of the control unit is explained using a flow-driven flowchart in which processing is performed sequentially according to a processing flow, but the present invention is not limited to this. In the present invention, the control processing of the control unit may be performed by event-driven processing in which processing is performed on an event-by-event basis. In this case, the control processing may be performed completely event-driven, or may be performed in a combination of event-driven and flow-driven processing.

[0099] 4 Control unit 100 Laser dicing device 301 Laser irradiation unit 302 Z direction moving unit (second moving unit) 303 Y direction moving unit (second moving unit) 306 X direction moving unit (first moving unit) 307 Chuck table unit (wafer holding unit) W Wafer ring structure We Wafer Wf Ring frame Wt Sheet member

Claims

1. A wafer holding unit that holds a wafer ring structure including a circular wafer, a sheet member to which the wafer is attached, and a ring frame that supports the sheet member; a laser irradiation unit that irradiates a laser onto the wafer held by the wafer holding unit to dice the wafer; a first movement unit that moves the wafer holding unit relative to the laser irradiation unit in a first horizontal direction; a second movement unit that moves the wafer holding unit relative to the laser irradiation unit in a second direction perpendicular to the first direction; and a control unit that controls the first movement unit to move the wafer holding unit in the first direction relative to the laser irradiation unit, and the laser irradiation unit to irradiate a laser to laser-machine the wafer along the first direction, The control unit of the laser dicing device controls the timing of the start of movement in the first direction by the first moving unit when performing laser processing on the second line of the wafer, based on the remaining movement distance or remaining movement time of the movement in the second direction by the second moving unit after laser processing on the first line along the first direction of the wafer, while moving in the second direction by the second moving unit, and then reversing the movement in the first direction by the first moving unit to perform laser processing on a second line along the first direction that is spaced apart from the first line in the second direction.

2. The laser dicing device of claim 1, wherein the first moving unit moves the wafer holding unit relative to the laser irradiation unit so that, after laser processing on the first line is completed and before laser processing on the second line is started, the first moving unit slows down, stops, and accelerates in the opposite direction to reach the processing speed in the first direction, and the control unit controls to adjust the timing of the start of movement in the first direction by the first moving unit when laser processing on the second line of the wafer is performed based on the remaining movement distance or remaining movement time of movement in the second direction by the second moving unit after laser processing on the first line is completed, so that at the laser processing start position on the second line, the movement speed in the first direction by the first moving unit reaches the processing speed and the movement position in the second direction by the second moving unit is on the second line.

3. The laser dicing device of claim 1, wherein the control unit acquires the movement position in the second direction by the second moving unit after laser processing on the first line is completed, and controls to adjust the timing at which the first moving unit starts moving in the first direction when laser processing the second line of the wafer is performed based on the acquired movement position in the second direction.

4. The laser dicing device of claim 1, wherein the control unit acquires the remaining movement time in the second direction by the second moving unit after laser processing on the first line is completed, and performs control to adjust the timing of the start of movement in the first direction by the first moving unit when performing laser processing on the second line of the wafer based on the acquired remaining movement time in the second direction.

5. The laser dicing device described in claim 2, wherein, when the distance traveled by the first moving unit in the first direction when decelerating is the same as the distance traveled by the first moving unit when accelerating, the control unit starts decelerating the movement in the first direction by the first moving unit after laser processing on the first line is completed at a position that is outer than the wafer between the processing end position on the first line and the processing start position on the second line, or at a position that is even outer than the position that is outer than the wafer.

6. The laser dicing device described in claim 2, wherein, after laser processing on the first line is completed, if the movement time in the second direction by the second moving unit is longer than the movement time in the first direction by the first moving unit, the control unit controls the first moving unit to start movement in the first direction when performing laser processing on the second line of the wafer at a time when the remaining movement time in the second direction by the second moving unit becomes less than or equal to the acceleration time in the first direction by the first moving unit.

7. The laser dicing device of claim 2, wherein, after laser processing on the first line is completed, if the movement time in the second direction by the second moving unit is shorter than the movement time in the first direction by the first moving unit, when the movement in the first direction by the first moving unit decelerates and stops, immediately controls the first moving unit to start movement in the first direction when laser processing the second line of the wafer.

8. The laser dicing device described in claim 2, wherein, when the speed at which the first moving unit decelerates and the speed at which it accelerates are different from each other when moving in the first direction by the first moving unit, the control unit controls to adjust the timing at which the first moving unit starts to decelerate its movement in the first direction after laser processing on the first line is completed so that the movement speed in the first direction by the first moving unit becomes the processing speed at the laser processing start position on the second line.

9. The laser dicing device according to claim 2, wherein the control unit performs control such that, when the speed at which the first moving unit decelerates in the first direction is the same as the speed at which it accelerates, and when the distance in the first direction from the processing end position on the first line to where it stops is greater than the distance from where it stops to the processing start position on the second line, the control unit starts decelerating the movement in the first direction by the first moving unit at the processing start position on the second line after laser processing on the first line is completed, and when the distance in the first direction from the processing end position on the first line to where it stops is equal to or less than the distance from where it stops to the processing start position on the second line, the control unit starts decelerating the movement in the first direction by the first moving unit at the processing end position on the first line after laser processing on the first line is completed.

10. The laser dicing device of claim 1, wherein the second moving unit moves the wafer holding unit relative to the laser irradiation unit in the second horizontal direction perpendicular to the first direction, and the control unit controls to adjust the timing of the start of movement in the first direction by the first moving unit when performing laser processing on the second line of the wafer, based on the remaining movement distance or remaining movement time of the second moving unit's horizontal movement in the second direction after laser processing on the first line is completed.

11. The laser dicing device of claim 1, wherein the second moving unit moves the wafer holding unit relative to the laser irradiation unit in the second direction, which is an up-and-down direction perpendicular to the first direction, and the control unit controls to adjust the timing of the start of movement in the first direction by the first moving unit when performing laser processing on the second line of the wafer, based on the remaining movement distance or remaining movement time of the second moving unit in the up-and-down direction after laser processing on the first line is completed.

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