JP7523864B2 - Cutting Equipment - Google Patents

Description

The present invention relates to a cutting device that cuts a workpiece held on a chuck table.

A cutting device is known that cuts various plate-shaped workpieces, such as semiconductor wafers, sapphire substrates, silicon carbide substrates, glass substrates, and resin package substrates, with a cutting blade along a planned dividing line set on the surface of the workpiece, thereby forming cutting grooves (cutting marks) in the workpiece.

When the cutting marks on the workpiece are observed with a camera unit after cutting, tiny chipping is usually observed. However, if poor cutting occurs during cutting for some reason, the size of the chipping can become abnormally large.

Therefore, a so-called kerf check is performed in which the cutting marks are photographed at appropriate times during cutting, and measurements are taken of multiple predetermined measurement items (e.g., width of the cutting marks, size of the chip, etc.) to automatically determine whether any cutting defects have occurred (see, for example, Patent Document 1).

JP 2013-74198 A

If a kerf check reveals that a cutting defect has occurred, it is necessary to eliminate the cause of the cutting defect, but an inexperienced operator may instruct the cutting device to continue cutting without eliminating the cause of the cutting defect. However, if cutting continues in this state, there is a risk that cutting defects will occur in all subsequent workpieces.

The present invention was made in consideration of these problems, and aims to provide a cutting device that can reduce the possibility of cutting defects occurring in subsequent cutting processes even if a cutting defect occurs once.

According to one aspect of the present invention, a cutting device includes a chuck table for holding a workpiece, a cutting unit having a spindle and cutting the workpiece held by the chuck table with a cutting blade attached to the spindle along a planned division line set on the workpiece, a camera unit for photographing the workpiece held by the chuck table, a sub-chuck table for holding a dressing board for dressing the cutting blade, and a control unit having a memory and a processor, wherein the control unit includes an image capturing instruction unit for causing the camera unit to capture an image of a first cutting mark on the workpiece cut by the cutting unit and obtain a cutting result image, and a cutting result image capturing unit for capturing a cutting result image of the first cutting mark on the cutting result image and a cutting result image capturing unit for capturing a cutting result image of the first cutting mark on the workpiece. The present invention provides a cutting device having a measuring unit that obtains measurement values of a plurality of measurement items each having a predetermined tolerance range, a dressing instruction unit that automatically dresses the cutting blade with the dressing board held by the sub-chuck table without issuing an alarm when the measurement value of at least one of the plurality of measurement items of the first cutting mark exceeds the tolerance range, and an alarm unit that causes the cutting device to issue an alarm when the measurement value of at least one of the plurality of measurement items of a second cutting mark formed at a position different from the first cutting mark in the indexing feed direction or on a workpiece different from the workpiece that was cut immediately before exceeds the tolerance range, in order to check whether there is a problem with the cutting mark immediately after dressing the cutting blade.

Preferably, the multiple measurements include kerf width, chip size, and chip area.

The dress instruction unit of the cutting device according to one aspect of the present invention dresses the cutting blade with a dressing board held by the sub-chuck table when the measured value of at least one of the multiple measurement items of the first cutting mark exceeds the allowable range.

In this way, even if a cutting defect occurs, the cutting device will automatically dress the cutting blade to try to eliminate the defect, reducing the possibility of the defect occurring in subsequent cutting processes.

Furthermore, after dressing the cutting blade, cutting of the workpiece is resumed, and a second cutting mark is automatically formed in a location different from the first cutting mark. Then, when the measured value of at least one of the multiple measurement items of this second cutting mark exceeds the allowable range, the notification unit causes the cutting device to issue an alarm.

In this way, if the cutting defect cannot be eliminated even after the cutting device performs dressing, the cutting device can issue an alarm to prompt the operator to eliminate the cause of the cutting defect. Therefore, for example, even an inexperienced operator can eliminate the cutting defect by calling an experienced operator. This reduces the possibility of cutting defects occurring in the subsequent cutting process.

FIG. FIG. 4 is a partial cross-sectional side view showing a state in which a workpiece is cut. FIG. 13 is a diagram showing an example of a cutting result image. FIG. 13 is a diagram showing an example of an image showing a plurality of measurement items. FIG. 13 is a diagram for explaining measurement values. FIG. 1 is a flow diagram of a cutting method using a cutting device.

An embodiment of one aspect of the present invention will be described with reference to the attached drawings. FIG. 1 is a perspective view of a cutting device 2. Note that FIG. 1 shows some of the components of the cutting device 2 in functional blocks. In addition, in the following description, the X-axis direction (machining feed direction), Y-axis direction (indexing feed direction), and Z-axis direction (up-down direction, height direction) are perpendicular to each other.

The cutting device 2 includes a base 4 that supports or houses each of the components. An opening 4a is formed in the front corner of the base 4, and within this opening 4a is provided a cassette elevator 6 that is raised and lowered by a lifting mechanism (not shown).

A cassette 8 for storing multiple workpieces 11 is placed on the upper surface of the cassette elevator 6. Here, the workpiece 11 will be described with reference to Figures 2 and 3. The workpiece 11 is, for example, a disk-shaped wafer made of a semiconductor material such as silicon.

On the surface 11a (see FIG. 2) of the workpiece 11, multiple mutually orthogonal planned division lines 13 (also called streets; see FIG. 3) are set. In each area partitioned by the multiple planned division lines 13, a device 15 (see FIG. 3) such as an IC (Integrated Circuit) is formed.

A dicing tape 17 having an area larger than that of the workpiece 11 is attached to the back surface 11b (see FIG. 2) of the workpiece 11. A ring-shaped frame 19 made of metal is attached to the outer periphery of the dicing tape 17.

As shown in FIG. 1, the workpiece 11 is housed in the cassette 8 as a workpiece unit 21 supported on a frame 19 via a dicing tape 17. There are no restrictions on the material, shape, structure, size, etc. of the workpiece 11.

A rectangular opening 4b with its long side along the X-axis direction is formed on the side of the cassette elevator 6. A ball screw type X-axis movement mechanism (processing feed unit) (not shown) is disposed below the opening 4b.

A rectangular table cover 12 is placed on top of the X-axis movement mechanism, and bellows-shaped covers 14 are placed on both sides of the table cover 12 in the X-axis direction. A chuck table 16 that holds the workpiece 11 is placed on the table cover 12.

A θ table (not shown) having a rotation drive source such as a motor is connected to the bottom of the chuck table 16. The θ table rotates the chuck table 16 within a predetermined angle range around a rotation axis that is approximately parallel to the Z-axis direction.

A suction passage (not shown) is formed inside the chuck table 16, and one end of the suction passage is connected to a suction source (not shown) such as a vacuum pump. The negative pressure generated by the suction source is transmitted to the upper surface of the chuck table 16.

The upper surface of the chuck table 16 is approximately parallel to the XY plane and functions as a holding surface 16a for suction-holding the workpiece 11. Four clamps 16b are provided around the periphery of the chuck table 16 for fixing the frame 19 from all sides.

Sub-chuck tables 18 are arranged at the corners of the table cover 12. In FIG. 1, two sub-chuck tables 18 are arranged at two corners on one side of the table cover 12 in the X-axis direction, spaced apart along the Y-axis direction.

Each sub-chuck table 18 is smaller than the chuck table 16 and is rectangular in top view. The flow path formed in the sub-chuck table 18 is connected to the suction source described above, and the upper surface of the sub-chuck table 18 serves as a holding surface for suction-holding the rectangular plate-shaped dress board 18a.

The dress board 18a is formed using a mixed material in which abrasive grains such as white alundum (WA) and green carbon (GC) are mixed with a binder such as vitrified or resinoid. The dress board 18a is used to dress (sharpen) the cutting blade 44, which will be described later.

A first transport unit (not shown) is disposed above the opening 4b, which transports the workpiece unit 21 to the chuck table 16. A gate-shaped support structure 20 is disposed to the side and above the opening 4b, straddling the opening 4b.

Two cutting unit movement mechanisms 22, each including an indexing feed unit and a cutting feed unit, are provided on the upper front surface of the support structure 20. Each cutting unit movement mechanism 22 shares a pair of Y-axis guide rails 24 that are disposed on the front surface of the support structure 20 and are substantially parallel to the Y-axis direction.

Y-axis moving plates 26 are slidably attached to the Y-axis guide rails 24. A nut portion (not shown) is provided on the back (rear) side of each Y-axis moving plate 26, and a Y-axis ball screw 28 that is approximately parallel to the Y-axis direction is rotatably connected to the nut portion.

One Y-axis pulse motor 30 is connected to one end of one Y-axis ball screw 28. When the Y-axis ball screw 28 is rotated by the Y-axis pulse motor 30, one Y-axis moving plate 26 moves along the Y-axis guide rail 24.

A pair of Z-axis guide rails 32 that are approximately parallel to the Z-axis direction are provided on the surface (front surface) of each Y-axis moving plate 26. A Z-axis moving plate 34 is slidably attached to the Z-axis guide rails 32.

A nut portion (not shown) is provided on the back side (rear side) of the Z-axis moving plate 34, and a Z-axis ball screw 36 that is approximately parallel to the Z-axis direction is rotatably connected to this nut portion. A Z-axis pulse motor 38 is connected to the upper end of the Z-axis ball screw 36.

When the Z-axis ball screw 36 is rotated by the Z-axis pulse motor 38, the Z-axis moving plate 34 moves along the Z-axis direction. The cutting unit 40 is connected to the lower part of the Z-axis moving plate 34. The cutting unit 40 has a square cylindrical spindle housing.

The spindle housing accommodates a portion of the cylindrical spindle 42 (see FIG. 2) in a rotatable manner. One end of the spindle 42 is connected to a rotation drive source (not shown) such as a servo motor.

An annular cutting blade 44 is attached to the other end of the spindle 42. The cutting blade 44 shown in FIG. 2 is a so-called hubless type (also called a washer type), but the cutting blade 44 may be a so-called hub type.

Returning to FIG. 1, a camera unit 46 is provided adjacent to each cutting unit 40. The camera unit 46 is equipped with a microscope camera having an image sensor such as a CMOS (Complementary Metal-Oxide-Semiconductor) or a CCD (Charge-Coupled Device), a predetermined optical system, and a lens.

The camera unit 46 photographs the front surface 11a of the workpiece 11 whose back surface 11b is held by the holding surface 16a. The image of the front surface 11a photographed by the camera unit 46 is used, for example, for aligning the workpiece 11 and analyzing the cutting results of the workpiece 11.

A circular opening 4c is provided at a position opposite opening 4b from opening 4a. A cleaning unit 48 is disposed within opening 4c for cleaning the workpiece 11 after cutting. The workpiece 11 after cutting is transported from the chuck table 16 to the cleaning unit 48 by a second transport unit (not shown).

Here, the procedure for cutting the workpiece 11 will be briefly described. FIG. 2 is a partially sectional side view showing how the workpiece 11 is cut. When cutting the workpiece 11, first, one workpiece unit 21 is removed from the cassette 8, and the back surface 11b side of the workpiece 11 is held by the holding surface 16a.

Next, one camera unit 46 photographs the surface 11a side, and based on the obtained image of the surface 11a side, the orientation of the chuck table 16 is adjusted using the θ table so that the planned division line 13 is approximately parallel to the X-axis direction.

Then, the cutting blade 44 is rotated at high speed and positioned on an extension of one of the planned division lines 13, and the lower end of the cutting blade 44 is positioned between the holding surface 16a and the back surface 11b.

In this state, when the cutting blade 44 and the chuck table 16 are moved relatively in the X-axis direction by the X-axis movement mechanism, the workpiece 11 is cut along one of the planned division lines 13, and a cutting mark (cutting groove) 13a is formed.

After forming cutting marks 13a along all of the planned division lines 13 along one direction, the chuck table 16 is rotated 90 degrees to make the planned division lines 13 along the other direction approximately parallel to the X-axis direction. Then, cutting marks 13a are formed along all of the planned division lines 13 along the other direction.

In this way, in the process of cutting the workpiece 11, for example, when the length cut by the cutting blade 44 reaches the kerf check condition described below, the camera unit 46 first photographs the cutting marks 13a in order to perform a kerf check. This results in an image 50 of the cutting result of the workpiece 11 (see FIG. 3).

Figure 3 shows an example of a cutting result image 50. The cutting result image 50 is used to obtain measurement values of the cutting mark 13a (kerf 25) for multiple predetermined measurement items, such as the size of the chipping (chipping) 23.

Now, let us return to FIG. 1. The cutting device 2 is provided with a display device 52 for displaying images captured by the camera unit 46, the above-mentioned measurement values, and the like. In this example, the display device 52 is, for example, a touch panel that functions as a display unit and an input unit.

If a problem occurs during the cutting process, the cutting device 2 can display an alarm on the display device 52 to indicate that an error has occurred. An indicator light 54 is provided on the top of the cutting device 2 to visually indicate the status of the cutting device 2.

The indicator light 54 lights up, for example, green when the cutting process is proceeding without any problems, and lights up, for example, red when a problem occurs during the cutting process. This red light is an alarm that the cutting device 2 issues to the operator, etc. Furthermore, the cutting device 2 may be provided with a speaker (not shown) that emits a specified warning sound (alarm) when a problem occurs during the cutting process.

The display device 52, indicator light 54, and speaker can function as an alarm unit that notifies the operator when a problem occurs during the cutting process. The cutting device 2 is provided with a control unit 56 that controls the operation of each component.

The control unit 56 controls the operation of the cassette elevator 6, the X-axis movement mechanism, the chuck table 16, the first and second transport units, the cutting unit movement mechanism 22, the cutting unit 40, the camera unit 46, the cleaning unit 48, the display device 52, the indicator light 54, the speaker, etc.

The control unit 56 is composed of a computer having a processor 58, such as a CPU (Central Processing Unit), and a memory 60 including a main memory device such as a DRAM (Dynamic Random Access Memory), an SRAM (Static Random Access Memory), or a ROM (Read Only Memory), and an auxiliary memory device such as a flash memory, a hard disk drive, or a solid state drive.

Software including a specific program is stored in the auxiliary storage device of memory 60. The functions of control unit 56 are realized by operating processor 58 in accordance with this software.

The memory 60 stores predetermined conditions that are input by the operator via the display device 52 or that are determined in advance according to the type of workpiece 11, etc. The predetermined conditions include cutting conditions such as the rotation speed of the cutting blade 44 and the processing feed speed of the chuck table 16.

The predetermined conditions further include kerf check conditions. The kerf check conditions are conditions for checking whether there are any problems with the cutting marks 13a, and for example, it is stipulated that a kerf check is performed when the workpiece 11 has been cut a predetermined cutting length.

In addition, instead of a predetermined length, it may be specified that the kerf check is performed when a predetermined number of workpieces 11 are cut. The operator can set or change the kerf check conditions as appropriate via the display device 52.

In addition to the above-mentioned cutting and kerf check conditions, the memory 60 also stores the tolerance ranges of multiple measurement items that are predetermined for the cutting marks 13a. Figure 4 shows an example of an image showing multiple measurement items that is displayed on a part of the display device 52.

The measurement values for each measurement item are obtained by the measurement unit 62, which is implemented by a program stored in the memory 60, by performing image processing on the cutting result image 50 to detect the edge 13b (see Figures 3 and 5) and by calculating the size of the characteristic area in the image.

For example, when detecting the edge 13b of the cutting mark 13a by image processing, the measurement unit 62 calculates the difference in brightness between adjacent pixels in the cutting result image 50. Note that the cutting mark 13a is displayed darker than the non-cutting area in the planned division line 13.

In the cutting result image 50, one pixel corresponds to, for example, 1 μm, so by calculating the number of pixels that make up the kerf 25 or chipping 23, the width of the kerf 25, the size of the chipping 23, etc. can be measured.

The multiple measurement items include contrast value 58a, deviation amount of center position 58b, width of kerf 25 excluding chipping 23 58c, width of kerf 25 including chipping 23 58d, maximum distance from hairline center to outer edge of chipping 23 58e, maximum size of chipping 23 58f, total area of chipping 23 58g, and deviation amount in Y-axis direction 58h (see Figure 4).

The contrast value 58a is a numerical value that indicates the contrast between the planned division line 13 and the cutting marks 13a in the cutting result image 50. In the image shown in FIG. 4, the contrast value 58a is displayed as the kerf score.

The lower limit of the contrast value 58a is displayed to the right of the kerf score. The higher the contrast value 58a, the greater the density of the planned division line 13 and the cutting marks 13a on the image, allowing for more accurate measurements.

The center position deviation amount 58b refers to the position deviation between the center line (not shown) of the hairline (reference line for the camera of the camera unit 46) and the center line 13c (see Figure 5) of the cutting mark 13a in the cutting result image 50.

If the deviation amount 58b exceeds the upper limit value shown to the right of the word (CALL), the control unit 56 notifies the operator of an error. Note that the upper limit value shown to the right of the word (CALL) is greater than the upper limit value shown to the right of the word (ADJUST).

If the deviation amount 58b exceeds the upper limit value shown to the right of the word (adjust) and is equal to or less than the upper limit value shown to the right of the word (call), the control unit 56 automatically performs hairline alignment and corrects the cutting position.

The width 58c of the kerf 25 excluding the chippings 23 (see FIG. 5) refers to the width of the kerf 25 excluding the multiple chippings 23 formed on both sides of the kerf 25 in the cutting result image 50. The upper and lower limit values of the width 58c are displayed to the right of the upper and lower limit characters, respectively.

The width 58d of the kerf 25 including chipping 23 (see FIG. 5) refers to the sum of the widths of the cutting marks 13a and chipping 23, including the size (length) of the largest chipping 23 in the width direction of the kerf 25 among the multiple chippings 23 formed on both sides of the kerf 25 in the cutting result image 50. The upper limit of the width 58d is displayed to the right of the characters (including chipping).

The maximum distance 58e from the hairline center to the outer edge of the chipping 23 means the distance from the center line of the hairline to the outer edge of the largest chipping 23 in the width direction of the kerf 25 in the cutting result image 50. The upper limit of the maximum distance 58e is displayed to the right of the characters (center to chipping).

The maximum chipping 23 size 58f (see FIG. 5) refers to the size (length) of the maximum chipping 23 in the width direction of the kerf 25 in the cutting result image 50. The upper limit of size 58f is displayed to the right of the chipping tolerance text.

The total area 58g of the chippings 23 means the sum of the areas of the chippings 23 (the areas shaded in black in FIG. 5) surrounded by the outer edges of each chipping 23 that protrude outward beyond the width 58c in the cutting result image 50 and the two imaginary straight lines that define the kerf 25. The upper limit of the total area 58g is displayed to the right of the characters for the chipping area.

The deviation amount 58h in the Y-axis direction means the deviation in the index feed direction between the actual target position on the cutting result image 50 and the target position calculated based on the index set by the device data.

A target is a target pattern used for alignment, etc., and is also called a key pattern, alignment mark, etc. The upper limit of the deviation amount 58h in the Y-axis direction is displayed to the right of the characters Y tolerance (by target) in the image.

In FIG. 4, the tolerance when the measurement unit 62 processes the cutting result image 50 obtained by one camera unit 46 is displayed in the Z1-axis column. Also, the tolerance when the measurement unit 62 processes the cutting result image 50 obtained by another camera unit 46 is displayed in the Z2-axis column.

Each measured value is stored in memory 60 and checked by control unit 56 to see if it exceeds the tolerance range. If the measured value exceeds the tolerance range (i.e., an error occurs), the action to be taken is preselected by the operator from among "CALL", "DRESS" and "RETRY".

"CALL" means to notify the operator of an error in the cutting device 2 by issuing an alarm via the display device 52, indicator light 54, speaker, etc. "DRESS" means to dress the cutting blade 44 using the dress board 18a.

"RETRY" means that the measurement unit 62 again processes the cutting result image 50 acquired by the camera unit 46, calculates the size of the characteristic area in the image, etc. In the example shown in FIG. 4, if the contrast value 58a is smaller than the lower limit, "CALL" processing is performed. Also, if the width 58c is smaller than the lower limit, "RETRY" processing is performed.

On the other hand, if the widths 58c, 58d, the maximum distance 58e, the size 58f, and the total area 58g are greater than their respective upper limits, the "DRESS" process is performed. Note that the selection of "CALL", "DRESS", and "RETRY" for each measurement item is not limited to the example shown in FIG. 4.

Figure 5 is an image 50a corresponding to the cutting result image 50, and is a diagram for explaining the measurement values. In image 50a, the edge 13b of the cutting mark 13a, the center line 13c of the cutting mark 13a, etc. are shown superimposed on the planned division line 13. Note that the device 15 is hatched.

Now, returning to FIG. 1, the configuration of the control unit 56 will be further described. The memory 60 includes an image capture instruction section 64 that causes the camera unit 46 to capture an image of the cutting marks 13a on the workpiece 11.

When the above-mentioned kerf check conditions are met, the photography instruction unit 64 causes the camera unit 46 to photograph the cutting marks 13a. The measurement unit 62 calculates each measurement item for the cutting result image 50 obtained by photography to obtain measurement values.

When at least one of the measured values for each measurement item exceeds the allowable range (i.e., when a cutting defect occurs), the control unit 56 operates the cutting unit 40, the cutting unit movement mechanism 22, the X-axis movement mechanism, the chuck table 16, etc. to dress the cutting blade 44 with the dressing board 18a.

In this manner, the instruction to automatically dress the cutting blade 44 is issued by the dressing instruction unit 66 in the control unit 56. The dressing instruction unit 66 is, for example, a program stored in the memory 60.

When dressing the cutting blade 44, for example, the rotating cutting blade 44 is positioned outside the dress board 18a in the X-axis direction, and the lower end of the cutting blade 44 is positioned at a predetermined depth from the upper surface of the dress board 18a. In this state, the cutting blade 44 and the dress board 18a are moved relatively in the X-axis direction by the X-axis movement mechanism.

Dressing prevents the cutting edge of the cutting blade 44 from becoming dull or clogged, reducing the size of chipping 23 during cutting and the frequency of chipping 23. When dressing, the cutting blade 44 may form one groove or multiple grooves in the dress board 18a.

In this manner, in this embodiment, when the measured value of at least one measurement item exceeds the allowable range, the cutting blade 44 is automatically dressed, so that even if a cutting defect occurs, the cutting device 2 can attempt to resolve the cutting defect. Therefore, the possibility of a cutting defect occurring in the subsequent cutting process can be reduced.

After the cutting blade 44 is dressed, cutting of the workpiece 11 is resumed. When cutting is resumed after dressing, a predetermined number of cutting marks 13a (for example, one) are newly formed at a different position in the index feed direction from the cutting marks 13a formed immediately before, or on a workpiece 11 different from the workpiece 11 that was previously cut.

One cutting mark 13a is formed on one planned division line 13. Then, in response to an instruction from the imaging instruction unit 64, a cutting result image 50 of the newly formed cutting mark 13a is acquired, and the measurement unit 62 calculates measurement values for multiple measurement items of the newly formed cutting mark 13a.

In this case, if the measured value of at least one measurement item exceeds the allowable range, the notification section 68 of the control unit 56 issues an alarm via the display device 52, indicator light 54, speaker, etc., to notify the operator that a cutting defect has occurred.

The notification unit 68 is realized, for example, by a program stored in the memory 60. When the notification unit 68 causes the cutting device 2 to issue an alarm, the operator can cancel the alarm by replacing the cutting blade 44, changing the cutting conditions such as the processing feed rate and the number of revolutions of the cutting blade 44, or increasing the tolerance ranges of multiple measurement items.

In this way, if the cutting device 2 cannot automatically eliminate the cutting defect, the cutting device 2 issues an alarm, urging the operator to eliminate the cause of the cutting defect. Therefore, for example, even an inexperienced operator can eliminate the cutting defect by calling an experienced operator. This reduces the possibility of cutting defects occurring in the subsequent cutting process.

Next, a cutting method using the cutting device 2 will be described with reference to FIG. 6. FIG. 6 is a flow diagram of the cutting method using the cutting device 2. When starting cutting of a predetermined number of workpieces 11, the operator touches the "Fully automatic start" button displayed on the display device 52.

When cutting multiple workpieces 11 using the cutting device 2, if the first workpiece 11 is to be cut (NO in S2), the workpiece 11 is held by the holding surface 16a, aligned, and cut by the cutting blade 44 (cutting step S4).

The workpiece 11 is cut sequentially along each of the planned division lines 13, and if the kerf check conditions are not met (NO in S6), the process returns to cutting step S4. On the other hand, if the kerf check conditions are met (YES in S6), the process proceeds to the first kerf check step S8.

In the first kerf check process S8, the photography instruction unit 64, for example, causes the camera unit 46 to photograph the cutting mark (first cutting mark) 13a that was just processed, thereby obtaining a cutting result image 50, and the measurement unit 62 obtains the measurement values of each measurement item based on the cutting result image 50.

If all the measurement values for the cutting marks 13a are within the allowable range (NO in S10), the process returns to S2. On the other hand, if at least one measurement value for the cutting marks 13a is outside the allowable range (YES in S10), the process proceeds to the dressing step S12.

In the dressing step S12, the cutting blade 44 is automatically dressed in response to instructions from the dressing instruction unit 66. This reduces the possibility of poor cutting in the subsequent cutting step S4.

After the dressing step S12, a confirmation cutting step S14 is performed. In the confirmation cutting step S14, a predetermined number of cutting marks 13a (for example, one) are newly formed at a position in the index feed direction different from the cutting marks 13a formed immediately before, or on a workpiece 11 different from the workpiece 11 that was previously cut.

Then, in response to an instruction from the photography instruction unit 64, a cutting result image 50 of the newly formed cutting mark 13a is acquired, and the measurement unit 62 calculates measurement values for multiple measurement items of the newly formed cutting mark (second cutting mark) 13a (second kerf check process S16).

If all the measured values are within the allowable range (NO in S18), the process returns to S2. On the other hand, if at least one measured value exceeds the allowable range (YES in S18), the alarm unit 68 causes the display device 52, the indicator light 54, the speaker, etc. to issue an alarm (alarm process S20).

When the process proceeds to the notification step S20, the control unit 56 temporarily stops the automatic cutting of the workpiece 11 by the cutting device 2. Then, unless the cause of the abnormality is eliminated and the alarm is deactivated, automatic cutting will no longer be performed even if the "Full auto start" button is touched.

Therefore, if the alarm is not cancelled (NO in S22), cutting ends. On the other hand, if the cause of the abnormality is eliminated and the alarm is cancelled (YES in S22), the control unit 56 activates the "Start full auto" button, and when the operator touches the "Start full auto" button, automatic cutting resumes (return to S2).

In this way, if the cutting device 2 cannot automatically eliminate the cutting defect, the cutting device 2 issues an alarm, urging the operator to eliminate the cause of the cutting defect. Therefore, for example, even an inexperienced operator can eliminate the cutting defect by calling an experienced operator. Therefore, the possibility of the occurrence of cutting defects in the subsequent cutting process S4 can be reduced.

In addition, the structures, methods, etc. according to the above embodiments can be modified as appropriate without departing from the scope of the present invention.

2: cutting device, 4: base, 4a, 4b, 4c: openings, 6: cassette elevator, 8: cassette, 12: table cover, 14: bellows-shaped cover, 11: workpiece, 11a: front surface, 11b: back surface, 13: planned division line, 13a: cutting marks, 13b: edge, 13c: center line, 15: device, 17: dicing tape, 19: frame, 21: workpiece unit, 16: chuck table, 16a: holding surface, 16b: clamp, 18: sub-chuck table, 18a: dress board, 20: support structure, 22: cutting unit moving mechanism, 23: chipping, 25: kerf, 24: Y-axis guide rail, 26: Y-axis moving plate 28: Y-axis ball screw, 30: Y-axis pulse motor 32: Z-axis guide rail, 34: Z-axis moving plate 36: Z-axis ball screw, 38: Z-axis pulse motor 40: Cutting unit, 42: Spindle, 44: Cutting blade 46: Camera unit, 48: Cleaning unit, 52: Display device, 54: Indicator light 50: Cutting result image, 50a: Image 56: Control unit, 58: Processor 58a: Contrast value, 58b: Displacement amount, 58c, 58d: Width, 58e: Maximum distance, 58f: Size, 58g: Total area, 58h: Displacement amount 60: Memory, 62: Measurement unit, 64: Photography instruction unit, 66: Dress instruction unit, 68: Notification unit

Claims (2)

A cutting device comprising:
A chuck table for holding the workpiece;
a cutting unit having a spindle and cutting the workpiece held by the chuck table along a planned dividing line set on the workpiece with a cutting blade attached to the spindle;
a camera unit for photographing the workpiece held by the chuck table;
a sub-chuck table for holding a dressing board for dressing the cutting blade;
a control unit having a memory and a processor;
The control unit
an image capturing instruction unit that causes the camera unit to capture an image of the cutting result by capturing a first cutting mark on the workpiece cut by the cutting unit;
a measurement unit that obtains measurement values of a plurality of measurement items, each of which has a predetermined tolerance range with respect to the cutting mark, based on the first cutting mark in the cutting result image;
a dress instruction unit that automatically dresses the cutting blade with the dress board held by the sub-chuck table without issuing an alarm when a measured value of at least one of the plurality of measurement items of the first cutting mark exceeds an allowable range;
a notification unit that causes the cutting device to issue an alarm when a measurement value of at least one of the plurality of measurement items of a second cutting mark formed at a position different from the first cutting mark in the indexing feed direction or on a workpiece different from the workpiece that was previously cut, exceeds the allowable range, in order to check whether there is a problem with the cutting mark immediately after dressing the cutting blade;
A cutting device comprising: The plurality of measurement items are:
Calf width and
The size of the defect and
2. The cutting device according to claim 1, further comprising: an area of the chipped portion.

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