JP6498073B2 - Method for detecting misalignment of cutting blade - Google Patents

Description

  The present invention relates to a cutting blade misalignment detection method for detecting misalignment of a cutting blade when a plate-like workpiece is divided by cutting with a cutting blade.

  When dividing a semiconductor wafer, an optical device wafer, a ceramic package substrate, or the like into a plurality of chips, for example, a cutting device including an annular cutting blade is used. The workpiece can be cut and divided into a plurality of chips by cutting a rotating cutting blade along the division lines (streets) set for these workpieces.

  In the above-described cutting apparatus, the position of the cutting blade is determined by, for example, a distance from a reference line set in a camera that images the workpiece. However, as the work of the workpiece progresses, the spindle serving as the rotating shaft of the cutting blade expands and contracts due to temperature change, and the position of the cutting blade tends to shift in the rotating shaft direction (index feed direction).

  Therefore, a method for confirming the position of the cutting blade with respect to the division planned line using a kerf (cut) formed by cutting has been proposed (see, for example, Patent Document 1). When the positional deviation of the cutting blade is detected by this method, the machining accuracy can be maintained by correcting the cutting blade feed amount (index feed amount).

JP-A-7-283171

  However, when the workpiece is divided into small chips under a condition where the feed amount is 0.3 mm or less, for example, the divided chips are easily moved by the force applied from the cutting blade. That is, the width of the kerf defined by the edge of the chip or the like is likely to fluctuate. Therefore, in the method of specifying the position of the cutting blade based on the edge of the kerf, the center position in the width direction, and the like, the positional deviation of the cutting blade may not be detected with high accuracy.

  The present invention has been made in view of such problems, and an object of the present invention is to provide a method for detecting a misalignment of a cutting blade capable of accurately detecting a misalignment of the cutting blade.

  According to the present invention, a chuck table for holding a workpiece, a cutting means for cutting the workpiece held on the chuck table with a cutting blade, and a machining feed means for moving the chuck table in the machining feed direction. A cutting apparatus comprising: an indexing feed means for moving the cutting means in an indexing feed direction perpendicular to the machining feed direction; and an imaging means for imaging a workpiece on which a reference line for positioning the cutting blade is set A cutting blade misalignment detection method for detecting misalignment in the indexing feed direction of the cutting blade when dividing a workpiece having a plurality of scheduled dividing lines using an apparatus, the method comprising: A reference distance setting step for setting a distance in the indexing feed direction with the cutting blade as a reference distance; and after performing the reference distance setting step, the chuck table An operation of cutting the cut workpiece by the cutting blade along the scheduled dividing line, and an operation of moving the cutting means in the indexing feed direction to align the cutting blade with the adjacent scheduled dividing line; Dividing the workpiece along the plurality of division lines, and cutting the workpiece along the division lines at an arbitrary timing during the division step. A measurement groove forming step for forming a measurement groove shallower than the thickness of the object, and an imaging step for forming an image by imaging the measurement groove of the workpiece by the imaging means during the division step; During the division step, the distance in the indexing feed direction between the measurement groove and the reference line is obtained based on the image, and the distance in the indexing feed direction between the measurement groove and the reference line and the reference Difference from distance Et al., A positional deviation detection step of detecting a positional deviation between the cutting blade and the dividing line, the position deviation detecting method of cutting blade provided is provided.

  In the cutting blade misalignment detection method according to the present invention, after performing the reference distance setting step of setting the distance in the indexing feed direction between the reference line and the cutting blade as the reference distance, the workpiece is divided along the planned dividing line. During the execution of the dividing step, a measuring groove forming step for forming a measuring groove shallower than the thickness of the workpiece, and an imaging step for forming an image by imaging the measuring groove with an imaging means are formed. Based on the obtained image, a distance in the indexing feed direction between the measurement groove and the reference line is obtained, and a positional deviation detection step for detecting a positional deviation between the cutting blade and the division planned line is obtained from the difference between the distance and the reference distance. carry out.

  That is, in the cutting blade position deviation detection method according to the present invention, since the position deviation between the cutting blade and the planned dividing line is detected based on the depth measurement groove that does not cut the work piece, the work piece is cut. As in the case of detecting the positional deviation between the cutting blade and the planned dividing line based on the kerf formed at the time, the detection accuracy is not lowered by the movement of the tip. Therefore, the positional deviation of the cutting blade can be detected with high accuracy.

It is a figure which shows the structural example of a cutting device typically. FIG. 2A is a diagram schematically illustrating the reference distance setting step, and FIG. 2B is a plan view schematically illustrating the reference distance setting step. FIG. 3A is a diagram schematically illustrating the dividing step and the measurement groove forming step, and FIG. 3B is a plan view schematically illustrating the imaging step. It is a figure which shows a position shift detection step typically.

  Embodiments of the present invention will be described with reference to the accompanying drawings. The cutting blade misalignment detection method according to this embodiment includes a reference distance setting step (see FIGS. 2A and 2B), a dividing step (see FIG. 3A), and a detection step. The detection step is composed of three steps: a measurement groove forming step (see FIG. 3A), an imaging step (see FIG. 3B), and a displacement detection step (see FIG. 4). To be implemented.

  In the reference distance setting step, the distance in the Y-axis direction (index feed direction) between the reference line set in the camera (imaging means) and the cutting blade is set as the reference distance. In the dividing step, the workpiece is divided along a plurality of division lines (streets). In the measurement groove forming step of the detection step, the workpiece is cut along the planned dividing line to form a measurement groove shallower than the thickness of the workpiece.

  In the imaging step of the detection step, an image is formed by imaging the measurement groove of the workpiece with a camera. In the misalignment detection step of the detection step, the distance in the Y-axis direction between the measurement groove and the reference line is obtained based on the formed image, and the cutting blade and the planned division line are determined from the difference between the distance and the reference distance. Detect misalignment. Hereinafter, a method for detecting misalignment of the cutting blade according to the present embodiment will be described in detail.

  First, an example of a cutting apparatus in which the method for detecting misalignment of a cutting blade according to this embodiment will be described. FIG. 1 is a diagram schematically illustrating a configuration example of a cutting apparatus according to the present embodiment. As shown in FIG. 1, the cutting device 2 includes a base 4 that supports each structure.

  A rectangular opening 4a is formed at the front corner of the base 4, and a cassette support base 6 is installed in the opening 4a so as to be movable up and down. A rectangular parallelepiped cassette 8 for accommodating a plurality of workpieces 11 is placed on the upper surface of the cassette support 6. In FIG. 1, only the outline of the cassette 8 is shown for convenience of explanation.

  The workpiece 11 is, for example, a circular wafer made of a semiconductor material such as silicon, and the surface 11a (see FIG. 3A, etc.) side has a central device region and an outer peripheral surplus region surrounding the device region. It is divided into. The device region is further divided into a plurality of regions by division lines (streets) 13 (see FIG. 3B) arranged in a lattice pattern, and devices 15 such as IC and LSI are formed in each region. Has been.

  A dicing tape 17 having a diameter larger than that of the workpiece 11 is attached to the back surface 11b (see FIG. 3A) of the workpiece 11. An outer peripheral portion of the dicing tape 17 is fixed to an annular frame 19. That is, the workpiece 11 is supported by the frame 19 via the dicing tape 17.

  In the present embodiment, a circular wafer made of a semiconductor material such as silicon is used as the workpiece 11. However, the material, shape, and the like of the workpiece 11 are not limited. For example, a substrate made of a material such as ceramic, resin, or metal can be used as the workpiece 11.

  A rectangular opening 4b that is long in the X-axis direction (front-rear direction, processing feed direction) is formed on the side of the cassette support base 6. Within this opening 4b, an X-axis moving table 10, an X-axis moving mechanism (processing feed means) (not shown) for moving the X-axis moving table 10 in the X-axis direction, and a dustproof and splashproof cover 12 that covers the X-axis moving mechanism. Is provided.

  The X-axis movement mechanism includes a pair of X-axis guide rails (not shown) parallel to the X-axis direction, and the X-axis movement table 10 is slidably attached to the X-axis guide rails. A nut portion (not shown) is provided on the lower surface side of the X-axis moving table 10, and an X-axis ball screw (not shown) parallel to the X-axis guide rail is screwed to the nut portion.

  An X-axis pulse motor (not shown) is connected to one end of the X-axis ball screw. By rotating the X-axis ball screw with the X-axis pulse motor, the X-axis moving table 10 moves in the X-axis direction along the X-axis guide rail.

  A chuck table 14 for holding the workpiece 11 is provided above the X-axis moving table 10. Around the chuck table 14, four clamps 16 for fixing an annular frame 19 that supports the workpiece 11 from four directions are installed.

  The chuck table 14 is connected to a rotation drive source (not shown) such as a motor, and rotates around a rotation axis substantially parallel to the Z-axis direction (vertical direction). The chuck table 14 is processed and fed in the X-axis direction by the above-described X-axis moving mechanism.

  The upper surface of the chuck table 14 is a holding surface 14 a that holds the workpiece 11. The holding surface 14a is connected to a suction source 20 (see FIG. 2 (FIG. 2A)) through a suction passage 14b (see FIG. 2 (A), etc.) formed inside the chuck table 14 and an on-off valve 18 (see FIG. 2 (A), etc.). A) etc.).

  A transport unit (not shown) for transporting the workpiece 11 described above to the chuck table 14 is provided at a position close to the opening 4b. The workpiece 11 transported by the transport unit is placed on the holding surface 14a of the chuck table 14 so that the surface side 11a is exposed upward, for example.

  On the upper surface of the base 4, a gate-type support structure 24 that supports two sets of cutting units (cutting means) 22 is disposed so as to straddle the opening 4 b. Two sets of cutting unit moving mechanisms (index feed means) 26 for moving each cutting unit 22 in the Y-axis direction (left-right direction, index feed direction) and the Z-axis direction are provided on the upper front surface of the support structure 24. .

  Each cutting unit moving mechanism 26 is commonly provided with a pair of Y-axis guide rails 28 arranged in front of the support structure 24 and parallel to the Y-axis direction. A Y-axis moving plate 30 constituting each cutting unit moving mechanism 26 is slidably attached to the Y-axis guide rail 28.

  A nut portion (not shown) is provided on the back side (rear side) of each Y-axis moving plate 30, and a Y-axis ball screw 32 parallel to the Y-axis guide rail 28 is screwed into each nut portion. Has been. A Y-axis pulse motor 34 is connected to one end of each Y-axis ball screw 32. When the Y-axis ball motor 32 is rotated by the Y-axis pulse motor 34, the Y-axis moving plate 30 moves in the Y-axis direction along the Y-axis guide rail 28.

  A pair of Z-axis guide rails 36 parallel to the Z-axis direction are provided on the surface (front surface) of each Y-axis moving plate 30. A Z-axis moving plate 38 is slidably attached to the Z-axis guide rail 36.

  A nut portion (not shown) is provided on the back surface side (rear surface side) of each Z-axis moving plate 38, and a Z-axis ball screw 40 parallel to the Z-axis guide rail 36 is screwed into each nut portion. Has been. A Z-axis pulse motor 42 is connected to one end of each Z-axis ball screw 40. When the Z-axis ball screw 40 is rotated by the Z-axis pulse motor 42, the Z-axis moving plate 38 moves in the Z-axis direction along the Z-axis guide rail 36.

  A cutting unit 22 is provided below each Z-axis moving plate 38. The cutting unit 22 includes an annular cutting blade 46 fixed to one end side of a spindle 44 (see FIG. 2A) serving as a rotating shaft. A camera (imaging means) 48 that images the workpiece 11 and the like is installed at a position adjacent to the cutting unit 22.

  In the camera 48, a reference line used for alignment of the cutting blade 46 is set. The reference line is, for example, a straight line that is substantially parallel to the X-axis direction (substantially perpendicular to the Y-axis direction), and is set like a hard wafer by a method of incorporating a glass plate with the straight line into an optical system. The Of course, the reference line may be set in software by a method of displaying a straight line on an image formed by the camera 48.

  The reference line is preferably set so that, for example, the positions of the reference line and the cutting blade 46 in the Y-axis direction substantially coincide. In this case, the position of the cutting blade 46 can be confirmed at a glance based on the reference line. However, the position of the reference line is not limited to this, and can be arbitrarily set and changed.

  If the Y-axis moving plate 30 is moved in the Y-axis direction by each cutting unit moving mechanism 26, the cutting unit 22 and the camera 48 are indexed and fed in the Y-axis direction perpendicular to the X-axis direction. Further, if the Z-axis moving plate 38 is moved in the Z-axis direction by each cutting unit moving mechanism 26, the cutting unit 22 and the camera 48 are moved up and down.

  A circular opening 4c is formed at a position opposite to the opening 4a with respect to the opening 4b. A cleaning unit 50 is provided in the opening 4c for cleaning the workpiece 11 after cutting. Components such as the X-axis moving mechanism, the chuck table 14, the cutting unit 22, the cutting unit moving mechanism 26, the camera 48, and the cleaning unit 50 are connected to the control unit 52.

  The control unit 52 includes a storage unit 52a for storing software for controlling each unit, cutting conditions (including a distance between a reference line and a cutting blade 46 described later), and the like. The operation of each part is controlled so that it can cut appropriately. The control unit 52 is connected to an input unit 54 for setting cutting conditions and the like.

  Next, a method for detecting the displacement of the cutting blade using the above-described cutting apparatus 2 will be described. In the cutting blade misregistration detection method according to the present embodiment, first, a reference distance setting step for setting a reference distance by obtaining a distance in the Y-axis direction (index feed direction) between the reference line of the camera 48 and the cutting blade 46 is performed. carry out.

  Specifically, the cutting blade 46 is cut into a workpiece for forming a kerf (cut), and a kerf indicating the position of the cutting blade 46 in the Y-axis direction is formed. Then, the kerf is imaged by the camera 48, and the distance in the Y-axis direction between the reference line and the cutting blade 46 is obtained from the formed image. The obtained distance is stored in the storage unit 52a and set in the cutting device 2 as a reference distance. FIG. 2A is a diagram schematically illustrating the reference distance setting step, and FIG. 2B is a plan view schematically illustrating the reference distance setting step.

  As shown in FIGS. 2A and 2B, as the workpiece 31 used in the reference distance setting step, for example, a wafer equivalent to the workpiece 11 can be used. However, a device need not be formed on the surface 31a. Further, a dresser board or the like for dressing the cutting blade 46 may be used as the workpiece 31.

  A dicing tape 33 having a diameter larger than that of the workpiece 31 is attached to the back surface 31 b side of the workpiece 31. An outer peripheral portion of the dicing tape 33 is fixed to an annular frame 35. That is, the workpiece 31 is supported on the frame 35 via the dicing tape 33.

  When forming the kerf on the workpiece 31, first, the workpiece 31, the dicing tape 33 and the frame 35 are placed on the chuck table 14 so that the surface 31 a side of the workpiece 31 is exposed upward. Then, the frame 35 is fixed by the clamp 16, and the on-off valve 18 is opened to apply the negative pressure of the suction source 20 to the holding surface 14a. As a result, the workpiece 31 is sucked and held by the chuck table 14.

  Next, the chuck table 14 and the cutting unit 22 are relatively moved so that the cutting blade 46 is aligned with an arbitrary position of the workpiece 31. Thereafter, the rotated cutting blade 46 is lowered to a height at which it contacts the workpiece 31, and the chuck table 14 is moved in the X-axis direction (machining feed direction).

  Thereby, the cutting blade 46 can be cut into the surface 31a side of the workpiece 31, and the kerf (cutting edge) 37 which shows the position of the cutting blade 46 in the Y-axis direction can be formed. In this reference distance setting step, a kerf 37 having a depth for cutting the workpiece 31 may be formed, or a kerf 37 (groove) having a depth for not cutting the workpiece 31 may be formed. .

  After the kerf 37 is formed on the workpiece 31, the kerf 37 included in the imaging area 48a is imaged by the camera 48 as shown in FIG. A reference line 48b set in the camera 48 is displayed on the image formed by the imaging. Therefore, the distance in the Y-axis direction between the kerf 37 and the reference line 48b can be obtained from this image.

  In the present embodiment, as the distance in the Y-axis direction between the cutting blade 46 and the reference line 48b, the distance in the Y-axis direction between the center position where the kerf 37 is equally divided in the width direction (Y-axis direction) and the reference line 48b. Ask. That is, in the present embodiment, the center position of the kerf 37 is handled as the position of the cutting blade 46 in the Y-axis direction. Note that the edge or the like of the kerf 37 may be handled as the position of the cutting blade 46 in the Y-axis direction.

  The obtained distance is stored in the storage unit 52a and set in the cutting device 2 as a reference distance. In the present embodiment, the reference distance is set to zero for convenience of explanation. That is, in the present embodiment, in the initial state, the position in the Y-axis direction of the reference line 48b and the position in the Y-axis direction of the cutting blade 46 (center position of the kerf 37) match.

  After the reference distance setting step, a division step for dividing the workpiece 11 along the plurality of division lines 13 is performed. FIG. 3A is a diagram schematically showing the dividing step and the measurement groove forming step.

  In the dividing step, first, the workpiece 11, the dicing tape 17 and the frame 19 are placed on the chuck table 14 so that the surface 11a side of the workpiece 11 is exposed upward. Then, the frame 19 is fixed by the clamp 16, and the on-off valve 18 is opened to apply the negative pressure of the suction source 20 to the holding surface 14a. Thereby, the workpiece 11 can be sucked and held by the chuck table 14.

  Next, the chuck table 14 and the cutting unit 22 are relatively moved and rotated to align the cutting blade 46 with the planned division line 13 extending in the first direction. Thereafter, the rotated cutting blade 46 is lowered to a height at which it comes into contact with the dicing tape 17, and the chuck table 14 is moved in the X-axis direction (machining feed direction). Thereby, the cutting blade 46 can be cut into the surface 11 a side of the workpiece 11, and the workpiece 11 can be cut along the target division line 13.

  After cutting the workpiece 11 along the target division line 13, the cutting blade 46 is raised to a height that does not contact the workpiece 11. Then, the cutting unit 22 is moved by a predetermined feed amount (index feed amount) in the Y-axis direction (index feed direction), so that the cutting blade 46 is aligned with the planned division line 13 adjacent to the target division line 13. Thereafter, the cutting blade 46 is cut into the surface 11 a side of the workpiece 11, and the workpiece 11 is similarly cut along the adjacent division line 13.

  After the above procedure is repeated and the workpiece 11 is cut along all the planned division lines 13 extending in the first direction, for example, the chuck table 14 is rotated by 90 ° and divided in the second direction. The workpiece 11 is cut along the scheduled line 13. When the workpiece 11 is cut along all the division lines 13, the division step ends.

  By the way, in this division step, the chip after the division is moved by the force applied from the cutting blade 46, and there is a possibility that the width of the formed kerf (cut edge) 21 will fluctuate. When the width of the kerf 21 fluctuates, the conventional method cannot detect the positional deviation of the cutting blade 46 with high accuracy.

  Therefore, in the present embodiment, a detection step of detecting the positional deviation of the cutting blade 46 without using the kerf 21 is performed during the division step. In the detection step, first, a measurement groove forming step for forming a measurement groove for detecting displacement in the workpiece 11 is performed. This measurement groove forming step is performed at an arbitrary timing during the dividing step.

  In the measurement groove forming step, first, the cutting unit 22 is moved by a predetermined feed amount in the Y-axis direction, and the cutting blade 46 is aligned with the scheduled division line 13 in which the kerf 21 is not formed (not cut).

  Next, the rotated cutting blade 46 is lowered to a height that does not reach the back surface 11b of the workpiece 11, and the chuck table 14 is moved in the X-axis direction. Thereby, the cutting blade 46 can be cut into the surface 11 a side of the workpiece 11, and the measurement groove 23 shallower than the thickness of the workpiece 11 can be formed along the target division line 13.

  After the measurement groove forming step, an imaging step of forming an image by imaging the measurement groove 23 of the workpiece 11 with the camera 48 is performed. FIG. 3B is a plan view schematically showing the imaging step.

  In the imaging step, the measurement groove 23 included in the imaging area 48a is imaged by the camera 48 as shown in FIG. A reference line 48b set in the camera 48 is displayed on the image formed by the imaging. Therefore, the distance in the Y-axis direction between the measurement groove 23 and the reference line 48b can be obtained from this image.

  After the imaging step, the distance in the Y-axis direction between the measurement groove 23 and the reference line 48b is obtained based on the image formed in the imaging step, and the cutting blade 46 is divided from the difference between the distance and the reference distance. A misalignment detection step for detecting misalignment with the planned line 13 is performed. FIG. 4 is a diagram schematically illustrating the misregistration detection step.

  In the misalignment detection step according to the present embodiment, as shown in FIG. 4, first, as shown in FIG. 4, the measurement groove 23 is equally divided into two in the width direction (Y-axis direction) in the Y-axis direction between the center position 23a and the reference line 48b. The distance D1 is obtained. The reason for obtaining such a distance D1 is that the center position of the kerf 37 is handled as the position of the cutting blade 46 in the Y-axis direction in the reference distance setting step.

  When the edge of the kerf 37 is handled as the position of the cutting blade 46 in the Y-axis direction in the reference distance setting step, the distance in the Y-axis direction between the edge of the measurement groove 23 and the reference line 48b may be obtained.

  After obtaining the distance D1, the distance D1 is compared with the reference distance to detect a positional deviation between the cutting blade 46 and the planned dividing line 13. For example, the positional deviation between the cutting blade 46 and the scheduled division line 13 can be detected by calculating the difference between the distance D1 corresponding to the positional deviation amount between the cutting blade 46 and the planned division line 13 and the reference distance. In the present embodiment, since the reference distance is set to zero, the distance D1 becomes the positional deviation amount between the cutting blade 46 and the division line 13 as it is.

  When the positional deviation amount is larger than a predetermined threshold value, it is desirable to correct the feed amount (index feed amount) of the cutting unit 22 in the Y-axis direction according to the positional deviation amount. Thereby, the position shift of the cutting blade 46 and the division | segmentation scheduled line 13 is suppressed, and the workpiece 11 can be divided | segmented accurately.

  As described above, in the cutting blade positional deviation detection method according to the present embodiment, the reference distance setting step of setting the distance in the Y-axis direction (index feed direction) between the reference line 48b and the cutting blade 46 as the reference distance is performed. Then, a measurement groove forming step for forming the measurement groove 23 shallower than the thickness of the workpiece 11 during the division step of dividing the workpiece 11 along the planned division line 13, and the measurement groove An image pickup step of forming an image by picking up the image 23 with a camera (image pickup means) 48, and a distance D1 in the Y-axis direction between the measurement groove 23 and the reference line 48b is obtained based on the formed image, and this distance D1 A misalignment detection step of detecting misalignment between the cutting blade 46 and the scheduled division line 13 is performed based on the difference from the reference distance.

  That is, in the cutting blade positional deviation detection method according to the present embodiment, the positional deviation between the cutting blade 46 and the planned division line 13 is detected based on the measurement groove 23 having a depth that does not cut the workpiece 11. The detection accuracy decreases due to the movement of the tip, as in the case of detecting the positional deviation between the cutting blade 46 and the planned dividing line 13 based on the kerf (cut edge) 21 formed when the workpiece 11 is cut. There is no. Therefore, for example, as shown in FIG. 3B, even when the width of the kerf (cutting edge) 21a is wider than the width of the other kerf (cutting edge) 21b, the positional deviation of the cutting blade 46 can be accurately performed. It can be detected.

  Note that the structures, methods, and the like according to the above-described embodiments can be appropriately modified and implemented without departing from the scope of the object of the present invention.

11 Workpiece 11a Front surface 11b Back surface 13 Scheduled line (street)
15 Device 17 Dicing tape 19 Frame 21, 21a, 21b Calf (cut)
23 Measurement Groove 31 Workpiece 31a Front 31b Back 33 Dicing Tape 35 Frame 37 Calf (Cut)
D1 Distance 2 Cutting device 4 Base 4a, 4b, 4c Open 6 Cassette support 8 Cassette 10 X-axis moving table 12 Dust-proof drip-proof cover 14 Chuck table 14a Holding surface 14b Suction path 16 Clamp 18 Open / close valve 20 Suction source 22 Cutting unit (Cutting means)
24 Support structure 26 Cutting unit moving mechanism (index feed means)
28 Y-axis guide rail 30 Y-axis moving plate 32 Y-axis ball screw 34 Y-axis pulse motor 36 Z-axis guide rail 38 Z-axis moving plate 40 Z-axis ball screw 42 Z-axis pulse motor 44 Spindle 46 Cutting blade 48 Camera (imaging means)
48a Imaging area 48b Reference line 50 Cleaning mechanism 52 Control unit 52a Storage unit 54 Input unit

Claims (1)

A chuck table for holding a workpiece, a cutting means for cutting the workpiece held on the chuck table with a cutting blade, a machining feed means for moving the chuck table in the machining feed direction, and the cutting means A plurality of cutting devices including an indexing feeding unit that moves in an indexing feeding direction perpendicular to the machining feeding direction, and an imaging unit that sets a reference line for alignment of the cutting blade and images a workpiece. A position deviation detection method for a cutting blade for detecting a position deviation in the indexing feed direction of the cutting blade when dividing the workpiece on which the division planned line is set,
A reference distance setting step for setting a distance in the indexing feed direction between the reference line and the cutting blade as a reference distance;
After performing the reference distance setting step, the workpiece held by the chuck table is cut by the cutting blade along the scheduled division line and cut, and the cutting means is moved in the indexing feed direction to be adjacent. Dividing the workpiece along the plurality of planned division lines by repeating the operation of aligning the cutting blade with the planned division lines to be performed, and
During the division step, the workpiece is cut along the planned division line at an arbitrary timing, and a measurement groove forming step for forming a measurement groove shallower than the thickness of the workpiece;
An imaging step of forming an image by imaging the measurement groove of the workpiece with the imaging means during the division step;
During the execution of the dividing step, the distance in the indexing feed direction between the measurement groove and the reference line is obtained based on the image, and the distance in the index feed direction between the measurement groove and the reference line and the reference distance. And a misregistration detecting step for detecting misregistration between the cutting blade and the scheduled division line.

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