JP2014067857A - Cutting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To recognize whether a flaw occurred on the upper surface of a workpiece or not before the cutting of the workpiece finishes.SOLUTION: A cutting device 1 stores the captured image of the upper surface of a workpiece W before cutting as a first captured image 30 in a first storage 22, stores the captured image of the upper surface of a workpiece W after cutting as a second captured image 31 in a second storage 23 and can recognize whether the upper surface of the workpiece W has a flaw or not by comparing the first captured image 30 and the second captured image 31 with a recognition part 24. Therefore, a cause of flaws can be found before the cutting of the workpiece W finishes and the whole surface of the workpiece W is prevented from being flawed.

Description

  The present invention relates to a cutting device for cutting a workpiece.

  Examples of the workpiece to be cut by the cutting apparatus include package substrates such as BGA (Ball Grid Array) and CSP (Chip Size Package). These package substrates are partitioned by a grid-like cut line to form a plurality of chips, and individual package devices are formed by cutting along the cut line. When the package substrate is cut along the cut line, scrap material is generated.

  In order to collect and process such offcuts, for example, a cutting apparatus disclosed in Patent Document 1 below has been proposed. In the cutting apparatus shown in FIG. 3 of Patent Document 1, a cutting waste processing apparatus is disposed around a movable range of a chuck table provided in the cutting apparatus.

JP 2006-315140 A

  However, in the above-described cutting device, it is possible to secure the end material falling together with the cutting water from the chuck table at the time of cutting by the cutting waste processing device, but until the end material falls from the holding table to the cutting waste processing device. In some cases, the top surface of the workpiece may be touched and scratched. In addition, the end material may get caught in the gap of the blade cover that supplies cutting water to the cutting blade, and the end of the sandwiched end material contacts the upper surface of the work piece and scratches the upper surface of the work piece. May end up.

  Further, in the above cutting apparatus, even if the upper surface of the workpiece is scratched during cutting, the upper surface of the workpiece is not inspected by the cutting apparatus, and after cutting the workpiece, the cutting apparatus is separated from the cutting apparatus. The inspection apparatus (handler apparatus) or packaging apparatus inspects whether or not the upper surface of the workpiece is scratched. Therefore, even if the workpiece is scratched during cutting, it cannot be recognized by the cutting device, and it is difficult to prevent the workpiece from being scratched.

  In addition, even when a scratch on the workpiece is discovered in a device other than the cutting device after cutting, since the next workpiece is started to be cut in the cutting device at the time of the discovery, the end material is caught in the blade cover. If the work piece is scratched due to this, the same work is also attached to the work piece to be cut next. Therefore, it is necessary to remove the cause of scratches by the end of cutting the workpiece.

  The present invention has been made in view of the above circumstances, and can recognize whether or not a scratch has occurred on the upper surface of the workpiece held by the holding table by the end of the cutting of the workpiece. There is a problem to be solved by the invention.

  The present invention includes a holding table for holding a workpiece, a cutting means having a spindle on which a cutting blade for cutting the workpiece held on the holding table is rotatably mounted, and cutting water for the cutting blade. Cutting water supply means for supplying, table moving means for moving the holding table in the cutting direction of the cutting blade mounted on the spindle, cutting water adhering to the upper surface of the workpiece held on the holding table, and A cutting device comprising at least a cleaning nozzle for cleaning cutting waste by jetting high-pressure air, and an imaging means for cleaning the upper surface of the workpiece by the cleaning nozzle and imaging the upper surface of the workpiece, A first storage unit for storing a first image of the upper surface of the workpiece imaged by the imaging unit before cutting the workpiece; and the imaging unit after cutting the workpiece. A second storage unit that stores a second captured image of the upper surface of the workpiece imaged in this manner, a first captured image that is stored in the first storage unit, and a second storage unit that is stored in the second storage unit. A recognition unit that recognizes a scratch on the upper surface of the workpiece by comparing with the second captured image.

  The imaging means is composed of a line-shaped line imaging unit that is longer than the width of the workpiece, and the line imaging unit is arranged such that the longitudinal direction of the line imaging unit is substantially orthogonal to the cutting direction of the cutting blade. The line imaging unit images the upper surface of the workpiece held by the holding table that is provided and is driven by the table moving means and passes below the line imaging unit.

  The cutting device according to the present invention stores a captured image of the upper surface of the workpiece before cutting in the first storage unit, and stores an captured image of the upper surface of the workpiece after cutting in the second storage unit. Since the recognition unit can compare the first captured image stored in the first storage unit with the second captured image stored in the second storage unit, the upper surface of the workpiece is It is possible to recognize whether there is a scratch. Therefore, it is possible to recognize whether or not the upper surface of the workpiece is flawed by the end of the cutting of the workpiece, and the cause of the flaw before the next workpiece is cut. Can be removed, and the formation of similar scratches on the workpiece to be cut next can be prevented. In addition, since scratches can be recognized before the cutting for all the cutting points of one workpiece is completed, by removing the cause of the scratches before cutting all the cutting points, Can prevent scratches when cutting the remaining cutting points,

  Further, the image pickup means is constituted by a line-shaped line image pickup section longer than the width of the workpiece, and the longitudinal direction of the line image pickup section is arranged substantially orthogonal to the cutting direction of the cutting blade, and the table moving means The entire surface of the workpiece can be imaged during the movement of the workpiece by configuring the line imaging unit to image the upper surface of the workpiece that is driven by and passes under the line imaging unit. Can and is efficient.

It is a perspective view which shows the structure of a cutting device. It is a side view which shows the state which images the upper surface of the workpiece before cutting. It is a top view which shows the positional relationship of the to-be-processed object hold | maintained at the holding table, and an imaging means. It is a top view which shows the captured image of a to-be-processed object. It is a side view which shows the state which images the upper surface of the workpiece after cutting, after cutting a workpiece. It is a side view which shows the state which conveys the workpiece after cutting.

  The cutting apparatus 1 shown in FIG. 1 has an apparatus base 2, and a rectangular cassette mounting part 2a is formed on the apparatus base 2, and a cassette 3 for accommodating a workpiece is placed in the cassette mounting part 2a. It is placed. In the vicinity of the cassette 3, a loading / unloading means 4 for unloading the workpiece accommodated in the cassette 3 and loading the workpiece into the cassette 3 is disposed. The carry-in / out means 4 includes a clamping part 4a that clamps a workpiece on the tip side, and can move the upper part 2b of the apparatus base 2 in the Y-axis direction.

  As shown in FIG. 1, a holding table 5 that holds a workpiece and can rotate is disposed in a movable range of the carry-in / out means 4. As shown in FIG. 2, the holding table 5 has a holding portion 5a formed of a porous member, and the upper surface of the holding portion 5a is a holding surface 5b for sucking and holding a workpiece. A suction hole 5c is formed below the holding portion 5a, and the suction hole 5c is connected to a suction source (not shown).

  As shown in FIG. 2, a guide portion 6 extending in the X-axis direction is disposed below the holding table 5 and supports the holding table 5 so as to be movable in the X-axis direction. The guide unit 6 is provided with table moving means 15 for moving the holding table 5 in the X-axis direction. As shown in FIG. 2, the table moving means 15 includes at least a ball screw 16 extending in parallel with the guide portion 6 and a motor 17 connected to one end of the ball screw 16. When the ball screw 16 is rotated by being driven by the motor 17, the holding table 5 can move horizontally in the X-axis direction along the guide portion 6.

  As shown in FIGS. 1 and 2, the cutting means 10 includes a rotatable spindle 11, a cutting blade 12 that can be rotated by being mounted on the spindle 11, and a blade cover 120 that rotatably covers the cutting blade 12. And at least. The cutting means 10 can rotate the cutting blade 12 at a predetermined rotational speed by the rotation of the spindle 11. In addition, as shown in FIG. 2, the area | region which cuts into a workpiece by the cutting means 10 is the cutting area P1.

  As shown in FIG. 2, a cutting water supply nozzle 13 is attached to the end of the blade cover 120 as a means for supplying cutting water toward the cutting blade 12. A cutting water supply source 14 that supplies cutting water to the cutting water supply nozzle 13 is connected to the upper end of the blade cover 120.

  As shown in FIG. 1, an image pickup unit 20 that picks up an image of the upper surface of the workpiece is disposed on the moving path of the holding table 5. As shown in FIG. 2, the imaging means 20 includes a first storage unit 22 that stores an imaged image obtained by imaging the upper surface of the workpiece before cutting, and an imaged image obtained by imaging the upper surface of the workpiece after cutting. Is formed on the upper surface of the workpiece by comparing the captured image stored in the first storage unit 22 with the captured image stored in the second storage unit 23. A recognition unit 24 that recognizes the presence or absence of scratches is connected.

  As shown in FIG. 3, it is desirable that the imaging unit 20 is configured by a line imaging unit 21 having a line shape longer than the width of the workpiece. The line imaging unit 21 is disposed so as to be substantially orthogonal to the direction (cutting direction) in which the cutting blade 12 included in the cutting means 10 shown in FIG. 2 rotates. The line imaging unit 21 includes, for example, an optical CCD image sensor or a CMOS image sensor. As shown in FIGS. 1 and 2, an area in which the upper surface of the workpiece is imaged by the imaging means 20 is an imaging area P2.

  The imaging unit 20 can also function as an alignment unit that images the upper surface of the workpiece before cutting and detects the position to be cut of the workpiece. Note that the imaging means 20 for imaging the workpiece is not limited to the line-shaped line imaging unit 21. In addition to the imaging unit 20, an alignment camera for detecting a position where the workpiece should be cut may be provided in the vicinity of the cutting unit 10.

  As shown in FIG. 2, a cleaning nozzle 18 is disposed in the vicinity of the imaging means 20, and this cleaning nozzle 18 is connected to an air source 19. The cleaning nozzle 18 can eject high-pressure air by the operation of the air source 19.

  A cleaning means 9 is disposed on the rear side of the apparatus base 2 in the Y-axis direction. In addition, above the cleaning unit 9, a transport unit 8 that transports the workpiece between the holding table 5 and the cleaning unit 9 is disposed. When the workpiece is carried in / out between the holding table 5 and the cassette 3 by the carry-in / out means 4 and when the workpiece is conveyed between the holding table 5 and the cleaning means 9. The holding table 5 is located in the transport area P3.

Below, operation | movement of the cutting device 1 comprised as mentioned above is demonstrated.
The workpiece W shown in FIG. 1 is not particularly limited, and is, for example, a package substrate such as a BGA (Ball Grid Array) and a CSP (Chip Size Package). As shown in FIG. 3, a plurality of devices D are formed on a workpiece W in a region partitioned by a grid-like cut line S, and a plurality of bumps B that are ball-shaped electrodes are arranged on the device D. ing. The workpiece W has a top surface on which a plurality of devices D are formed. When the workpiece W is cut, as shown in FIG. 1, the workpiece W is formed integrally with the annular frame F via the protective tape T, and a plurality of the workpieces W are accommodated in the cassette 3.

  The carrying-in / out means 4 shown in FIG. 1 clamps the frame F by the clamping part 4a, and takes out one workpiece W integrated with the frame F from the cassette 3 via the protective tape T. Thereafter, the carry-in / out means 4 moves above the apparatus base 2 in the Y-axis direction and places the workpiece W on the holding table 5 that stands by in the conveyance area P3. The holding table 5 sucks and holds the workpiece W on the holding surface 5b.

  As shown in FIG. 2, the table moving means 15 rotates the ball screw 16 by driving the motor 17 to move the holding table 5 in the X-axis direction at a predetermined feed speed. As shown in FIG. 3, when the workpiece W that moves in the X-axis direction passes below the imaging means 20, the line imaging unit 21 displays the upper surface of the workpiece W before cutting held by the holding table 5. Image. And the imaging means 20 memorize | stores the captured image before cutting in the 1st memory | storage part 22 as the 1st captured image 30 shown to Fig.4 (a). The first captured image 30 is useful later in determining whether there is a scratch on the upper surface of the workpiece. Further, the imaging unit 20 detects the cut line S to be cut by the cutting unit 10. Then, the cutting line S to be cut and the cutting blade 12 are aligned.

  Next, with the cutting blade 10 shown in FIG. 2 rotated at high speed in the direction of arrow A while the cutting means 10 is lowered and the cutting blade 12 is positioned at a predetermined height, the table moving means 15 shown in FIG. By operation, the holding table 5 is further moved in the X-axis direction, and the cutting blade 12 is cut into the cut line S of the workpiece W as indicated by a two-dot chain line. When the holding table 5 is further moved in the same direction, the cut line S is cut. At this time, the cutting water supply nozzle 13 releases the cutting water supplied from the cutting water supply source 14 toward the rotating cutting blade 12.

  Due to the cutting of the workpiece W, the end material around the device D may scatter and fall onto the upper surface of the workpiece W, which may scratch the upper surface of the workpiece W. Further, for example, when an end material is caught in the gap between the blade cover 120 and the cutting blade 12, if the workpiece is cut and fed while the end material is held, the workpiece is processed by the end material. Things W may be scratched. Therefore, in order to recognize whether or not a scratch is generated on the upper surface of the workpiece W during cutting, the upper surface of the workpiece W is imaged by the imaging means 20 after the cutting. For example, the upper surface of the workpiece W is imaged after cutting the row of cut lines S formed in the X-axis direction formed on the workpiece W shown in FIG. 3 and compared with the image before imaging. It is determined whether there is a scratch on the upper surface of the object W. Note that the timing of imaging is not limited to before and after cutting of one row of cut lines S, and may be before and after cutting of a plurality of cut lines, for example.

  Before the cutting of one cut line S, a first captured image is stored in the first storage unit 22 as an image before cutting. On the other hand, after cutting one cutting line S, in the process in which the holding table 5 moves away from the cutting means 10, high pressure air is ejected from the cleaning nozzle 18 toward the workpiece W, thereby cutting water. And after removing cutting waste, the upper surface of the workpiece W is imaged by the line imaging unit 21. And the image of the upper surface of the workpiece after the cutting is memorize | stored in the 2nd memory | storage part 23 as a 2nd captured image.

  The recognition unit 24 illustrated in FIG. 5 compares the first captured image 30 illustrated in FIG. 4A with the second captured image 31 illustrated in FIG. It is determined whether or not there is a scratch on the device D. At this time, the second captured image is an image after cutting, and there is a cutting groove that did not exist before cutting. Therefore, the portion of the cutting groove is excluded from comparison by applying a mask.

  For example, as shown in FIG. 4B, a straight scratch 40 that is not present in the first captured image 30 is formed over the plurality of devices D in the second captured image 31 after the mask is applied. If it is, the recognition unit 24 recognizes that the workpiece W is scratched. Such scratches are caused by moving the holding table 5 in the X-axis direction while the end material is sandwiched in the gap between the blade cover 120 and the cutting blade 12 shown in FIG. It can be recognized that the cutting flaw 40 has occurred.

  Therefore, when the recognition unit 24 recognizes that the workpiece W has such a scratch, the end material sandwiched in the gap between the blade cover 120 and the cutting blade 12 shown in FIG. 5 is removed. Thereafter, the table moving means 15 shown in FIG. 5 moves the holding table 5 to the cutting area P <b> 1 and continues cutting the workpiece W by the cutting means 10.

  After one cut line S is cut, the cutting means 10 is indexed in the Y-axis direction so that the adjacent cut line S and the cutting blade 12 are aligned, and the same cutting is repeated. In this way, all the cut lines S in the same direction are cut. When the same cutting is performed after the holding table 5 is rotated 90 degrees, all the cut lines S are cut vertically and horizontally and divided into individual devices D. Whether or not scratches are formed on the upper surface of the workpiece by imaging the upper surface of the workpiece W before and after the cutting of all the cut lines S performed in this way and comparing the two images before and after the cutting. Can be recognized.

  After the workpiece W has been cut, as shown in FIG. 6, the table moving means 15 rotates the ball screw 16 by driving the motor 17 and conveys the holding table 5 holding the workpiece W. Move to region P3.

  As shown in FIG. 6, when the holding table 5 has moved to the transport area P <b> 3, the annular frame F is sucked and held by the plurality of suction portions 8 a constituting the transport means 8. Then, the transport unit 8 moves in the Y-axis direction shown in FIG. 1 and transports the workpiece W to the cleaning unit 9. The cleaning unit 9 cleans and dries the upper surface of the workpiece W while rotating the workpiece W and supplying cleaning water from the cleaning water supply nozzle 9a.

  Thereafter, the workpiece W is transported to the transport region P3 by the transport means 8 and then accommodated in the cassette 3 by the transport-in / out means 4.

  As described above, the cutting apparatus 1 images the upper surface of the workpiece before cutting the workpiece, stores the first captured image in the first storage unit 22, and cuts the workpiece. Later, the upper surface of the workpiece is imaged and the second captured image is stored in the second storage unit 23, and the recognition unit 24 compares the first captured image and the second captured image to compare the workpiece. Since scratches on the upper surface can be recognized, it is possible to recognize whether or not scratches have occurred on the upper surface of the workpiece by the end of the cutting of the workpiece, so that the next workpiece can be cut. It is possible to remove the cause of scratches before starting the process, and it is possible to prevent the formation of similar scratches on the workpiece to be cut next. In addition, since the scratch can be recognized before the cutting of all the cut lines of one workpiece is completed, by removing the cause of the scratch before cutting all the cut lines, Scratches can be prevented during the cutting of the remaining cut lines, and the entire surface of the workpiece is not scratched at the end of the cutting of the workpiece.

  In addition, since the image pickup unit 20 configured by the line-shaped line image pickup unit 21 longer than the width of the workpiece W is provided, the workpiece W before and after cutting in the process of moving the workpiece. The entire upper surface of the image can be imaged, which is efficient.

1: Cutting device 2: Device base 2a: Cassette mounting portion 2b: Upper portion 3: Cassette 4: Loading / unloading means 4a: Holding portion 5: Holding table 5a: Holding portion 5b: Holding surface 6: Guide portion 8: Conveying means 8a : Adsorbing part 9: Cleaning means 9a: Cleaning water supply nozzle 10: Cutting means 11: Spindle 12: Cutting blade 120: Blade cover 13: Cutting water supply nozzle 14: Cutting water supply source 15: Table moving means 16: Ball screw 17: Motor 18: Cleaning nozzle 19: Air source 20: Imaging means 21: Line imaging unit 22: First storage unit 23: Second storage unit 24: Recognition unit 30: First captured image 31: Second captured image
40: Cutting scratch W: Work piece B: Bump D: Device S: Cut line T: Protective tape F: Frame

Claims (2)

A holding table for holding the workpiece;
Cutting means comprising a spindle on which a cutting blade for cutting a workpiece held on the holding table is rotatably mounted;
Cutting water supply means for supplying cutting water to the cutting blade;
Table moving means for moving the holding table in the cutting direction of the cutting blade mounted on the spindle;
A cleaning nozzle for cleaning the cutting water and the cutting waste adhering to the upper surface of the workpiece held by the holding table by jetting high-pressure air;
An imaging means for cleaning the upper surface of the workpiece by the cleaning nozzle and imaging the upper surface of the workpiece;
A first storage unit for storing a first captured image of the upper surface of the workpiece imaged by the imaging means before cutting the workpiece;
A second storage unit for storing a second captured image of the upper surface of the workpiece imaged by the imaging means after cutting the workpiece;
A recognition unit for comparing the first captured image stored in the first storage unit and the second captured image stored in the second storage unit to recognize a scratch on the upper surface of the workpiece; A cutting apparatus comprising: The imaging means is constituted by a line-shaped line imaging unit longer than the width of the workpiece,
The line imaging unit is arranged such that the longitudinal direction of the line imaging unit is substantially orthogonal to the cutting direction of the cutting blade,
The cutting apparatus according to claim 1, wherein the line imaging unit images the upper surface of the workpiece held by the holding table that is driven by the table moving unit and passes under the line imaging unit.

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