JP6562725B2 - Cutting equipment - Google Patents

Description

  The present invention relates to a cutting apparatus.

  A cutting blade used for dividing a semiconductor wafer or forming a groove is worn by cutting, and maintains its sharpness with a self-generated blade due to wear. Ideally, the wear of the cutting blade should be reduced in diameter while maintaining its tip shape. However, when the cutting blade is not suitable for processing conditions or when processing is performed in which a load is locally applied to the cutting blade, the tip shape is not evenly worn left and right. Alternatively, even if the cutting blade is worn evenly on the left and right, a so-called uneven wear phenomenon may occur in which a curved surface having a half or less of the blade thickness is formed at the tip and the tip is tapered.

  If such a situation continues, the cutting blade may be damaged, a large amount of chipping (chip) may occur on one side of the cutting groove, or a desired groove shape may not be obtained. Thus, a method has been devised that can detect the tip shape of the cutting blade even during the cutting of the workpiece (for example, see Patent Document 1).

JP 2011-41878 A

  However, since the method disclosed in Patent Document 1 uses an image obtained by imaging one end of the cutting groove from above, the length of the photographed cutting groove is very long compared to the cross-sectional shape of the cutting blade. For this reason, the method shown in Patent Document 1 has a problem that it is difficult to easily capture the cross-sectional shape of the outer periphery of the cutting blade, and it is difficult to grasp the cross-sectional shape of the outer periphery of the cutting blade.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a cutting apparatus capable of easily grasping the cross-sectional shape of the outer periphery of the cutting blade.

In order to solve the above-described problems and achieve the object, a cutting apparatus according to the present invention cuts a workpiece held by the chuck table with a holding surface and a workpiece held by the chuck table with a cutting blade. A cutting apparatus comprising: a cutting unit; an imaging unit that captures an image of a workpiece held on the chuck table from a direction orthogonal to the holding surface; and an image processing unit that processes an image captured by the imaging unit. The imaging means captures a captured image by capturing the one end where the outer peripheral shape of the cutting blade appears in the detection groove where one end is formed by cutting a part of the workpiece with a cutting blade, The image processing means includes at least a part of the captured image including one end of the detection groove so that a length of the image is a length viewed from a tangential direction of a circle formed by the outer periphery of the cutting blade. Of some images Is reduced to form an image that approximates the outer circumferential shape of the cutting blade, characterized in that it comprises display means for displaying the image.

In the cutting apparatus, the image processing means divides the captured image into a plurality of divided images in the longitudinal direction of the groove the detectable, longitudinal length of the detection groove of the divided image is cut該切blade The length in the longitudinal direction of the divided image can be reduced so as to have a length viewed from the tangential direction, and the image approximating the outer peripheral shape of the cutting blade can be formed.
In the above cutting apparatus, the image processing means performs pattern matching between the image and an image of a cross-sectional shape of a non-defective cutting blade, and notifies when the correlation value is lower than a predetermined value. Can do.
In the cutting apparatus, the image processing means has a radius of the cutting blade as R, a cutting depth of the cutting blade as d, and the tangent of the detection groove of the divided image including one end of the detection groove. The maximum depth when viewed from the direction is α, and the length L in the longitudinal direction of the detection groove of the divided image is L = ((R ² − (R−d) ² ) ^1/2 − ( (R−α) ² − (R−d) ² ) ^1/2 and calculating the length L in the longitudinal direction of the detection groove of each divided image, When each divided image is n-th from the divided images including one end of the groove, R = R−n × α is calculated, and each length of the divided images is set so that the length L in the longitudinal direction is α. Pixels of the image are removed, the length of the divided image in the longitudinal direction is reduced, and the image approximating the outer peripheral shape of the cutting blade is formed. Door can be.

  Therefore, the cutting device of the present application reduces at least a part of the image including one end of the detection groove of the captured image to a length viewed from the tangential direction of the cutting blade, so that the cross-sectional shape of the outer periphery of the cutting blade is grasped. There is an effect that it can be easily performed.

FIG. 1 is a perspective view illustrating a configuration example of a cutting apparatus according to an embodiment. 2A is a cross-sectional view of the outer periphery of a normally worn cutting blade of the cutting apparatus shown in FIG. 2B is a cross-sectional view of an example of the outer periphery of the cutting blade that is abnormally worn by the cutting apparatus shown in FIG. 1. FIG. 2C is a cross-sectional view of another example of the outer periphery of the cutting blade that is abnormally worn by the cutting apparatus shown in FIG. 1. 2D is a cross-sectional view of still another example of the outer periphery of the cutting blade that is abnormally worn by the cutting apparatus shown in FIG. 2E is a cross-sectional view of still another example of the outer periphery of the cutting blade abnormally worn by the cutting apparatus shown in FIG. FIG. 3 is a flowchart of an example of a method for grasping the wear state of the outer periphery of the cutting blade of the cutting apparatus according to the embodiment. FIG. 4 is a cross-sectional view schematically showing a state in which the cutting means of the cutting apparatus according to the embodiment forms a detection groove. FIG. 5 is a perspective view showing a workpiece in which a detection groove is formed by the cutting means of the cutting apparatus according to the embodiment. 6 is an enlarged plan view showing a VI part in FIG. FIG. 7 is a diagram illustrating a captured image obtained by imaging the detection groove illustrated in FIG. 6. FIG. 8 is a view showing an image displayed on the display means by reducing the length of the captured image shown in FIG. FIG. 9 is a cross-sectional view of the outer periphery of the cutting blade in which the detection groove shown in FIG. 6 is formed. 10 is a view showing a longitudinal section in a direction parallel to the street of the detection groove shown in FIG. FIG. 11 is a diagram illustrating a captured image obtained by imaging by the imaging unit of the cutting apparatus according to the first modification of the embodiment. FIG. 12 is a diagram illustrating an image displayed on the display unit by reducing the length of the divided image of the captured image illustrated in FIG. 11. FIG. 13 is a cross-sectional view schematically showing a state in which the cutting means of the cutting apparatus according to the second modification of the embodiment forms a detection groove. FIG. 14 is a view showing a longitudinal section in a direction parallel to the street of the detection groove formed by the cutting means of the cutting apparatus according to the third modification of the embodiment. FIG. 15 is a captured image obtained by imaging one end of the detection groove formed on the workpiece of the example. FIG. 16 is an image obtained by reducing the captured image shown in FIG. FIG. 17 shows a cross-sectional shape of the detection groove shown in FIG.

  DESCRIPTION OF EMBODIMENTS Embodiments (embodiments) for carrying out the present invention will be described in detail with reference to the drawings. The present invention is not limited by the contents described in the following embodiments. The constituent elements described below include those that can be easily assumed by those skilled in the art and those that are substantially the same. Furthermore, the structures described below can be combined as appropriate. Various omissions, substitutions, or changes in the configuration can be made without departing from the scope of the present invention.

Embodiment
A cutting apparatus according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a perspective view illustrating a configuration example of a cutting apparatus according to an embodiment. 2A is a cross-sectional view of the outer periphery of a normally worn cutting blade of the cutting apparatus shown in FIG. FIG. 2B is a cross-sectional view of an example of the outer periphery of the cutting blade that is abnormally worn by the cutting apparatus shown in FIG. 1. FIG. 2C is a cross-sectional view of another example of the outer periphery of the cutting blade that is abnormally worn by the cutting apparatus shown in FIG. 1. 2D is a cross-sectional view of still another example of the outer periphery of the cutting blade that is abnormally worn by the cutting apparatus shown in FIG. 2E is a cross-sectional view of still another example of the outer periphery of the cutting blade abnormally worn by the cutting apparatus shown in FIG.

  The cutting apparatus 1 shown in FIG. 1 according to the embodiment is an apparatus that cuts the workpiece W and divides the workpiece W into individual devices D. In this embodiment, the workpiece W divided into the individual devices D by the cutting apparatus 1 is a disk-shaped semiconductor wafer or optical device wafer using silicon, sapphire, gallium, or the like as a base material. As shown in FIG. 1, the workpiece W is formed with devices D in respective regions partitioned by streets S formed in a lattice shape on the upper surface Wa. The workpiece W includes a device region DR in which the device D is formed, and an outer peripheral surplus region GR that surrounds the device region DR and in which the device D is not formed. The workpiece W has a dicing tape T attached to the back surface on the back side of the upper surface Wa, an annular frame F attached to the dicing tape T, and attached to the annular frame F via the dicing tape T. The workpiece W is cut along the street S by the cutting apparatus 1 and divided into individual devices D.

  As shown in FIG. 1, the cutting apparatus 1 includes a chuck table 10 that holds a workpiece W on a holding surface 10 a, and a cutting means 20 that cuts the workpiece W held on the chuck table 10 with a cutting blade 21. An X-axis moving means (not shown) that moves the chuck table 10 and the cutting means 20 in the X-axis direction relatively, and a Y-axis that relatively moves the chuck table 10 and the cutting means 20 in the X-axis direction. Y-axis moving means 40 that moves in the direction, Z-axis moving means 50 that relatively moves the chuck table 10 and the cutting means 20 in the vertical direction (Z-axis direction), and an axis parallel to the Z-axis. A rotation drive source (not shown) that rotates around the center, an imaging unit 30, a control unit 100, and the like are provided.

  The cutting apparatus 1 also cleans the workpiece W after cutting, a cassette elevator 60 that houses a plurality of workpieces W before and after cutting, a loading / unloading means (not shown) that puts and removes the workpiece W into and from the cassette elevator 60. Cleaning means 70 for carrying out, a conveying means (not shown) for conveying the workpiece W across the carry-in / out means, the chuck table 10 and the cleaning means 70.

  The chuck table 10 is installed on the apparatus main body 2, the workpiece W before cutting is placed on the holding surface 10 a, and the workpiece is attached to the opening of the annular frame F via the dicing tape T. The object W is held. The chuck table 10 has a disk shape in which a portion constituting the holding surface 10a is formed of porous ceramic or the like, and is connected to a vacuum suction source (not shown) via a vacuum suction path (not shown) and placed on the holding surface 10a. The workpiece W is held by being sucked. The chuck table 10 is rotated about a central axis (parallel to the Z axis) by a rotational drive source installed on a table moving base (not shown) provided movably in the X axis direction by the X axis moving means. It is provided to be freely rotatable. Further, around the chuck table 10, a plurality of clamp portions 12 that are driven by an air actuator and sandwich the annular frame F around the workpiece W are provided.

  The cutting means 20 has a spindle equipped with a cutting blade 21 for cutting the workpiece W held on the chuck table 10. The cutting means 20 is provided so as to be movable in the Y-axis direction by the Y-axis moving means 40 with respect to the workpiece W held on the chuck table 10, and is movable in the Z-axis direction by the Z-axis moving means 50. Is provided.

  As shown in FIG. 1, the cutting means 20 is provided on the column portion 3 erected from the apparatus main body 2 via a Y-axis moving means 40, a Z-axis moving means 50, and the like. The cutting means 20 can position the cutting blade 21 at an arbitrary position on the surface of the chuck table 10 by the Y-axis moving means 40 and the Z-axis moving means 50.

  Further, the cutting means 20 is fixed so that the imaging means 30 for imaging the upper surface Wa of the workpiece W moves integrally. The imaging means 30 includes a CCD camera that captures an area to be divided of the workpiece W before being divided and held by the chuck table 10. The CCD camera images the workpiece W held on the chuck table 10 to obtain an image for performing alignment for aligning the workpiece W and the cutting blade 21, and controls the obtained image as a control means. Output to 100. The CCD camera, that is, the imaging unit 30 opposes the holding surface 10a in parallel with the Z-axis direction, and images the upper surface Wa of the workpiece W held on the chuck table 10 from above, which is a direction orthogonal to the holding surface 10a.

  The cutting blade 21 is an extremely thin cutting grindstone having a substantially ring shape. The spindle cuts the workpiece W by rotating the cutting blade 21. The spindle is accommodated in the spindle housing 23, and the spindle housing 23 is supported by the Z-axis moving means 50. The spindle of the cutting means 20 and the axis of the cutting blade 21 are set parallel to the Y-axis direction.

  The X-axis moving means realizes machining feed for the workpiece W by moving the chuck table 10 in the X-axis direction. The Y-axis moving unit 40 realizes the index feed with respect to the workpiece W by moving the cutting unit 20 in the Y-axis direction. The Z-axis moving means 50 realizes control of the cutting depth with respect to the workpiece W by moving the cutting means 20 in the Z-axis direction.

  The control means 100 controls the above-described components constituting the cutting device 1 to cause the cutting device 1 to perform a machining operation on the workpiece W. The control means 100 is mainly composed of an arithmetic processing unit constituted by, for example, a CPU or the like and a microprocessor (not shown) provided with a ROM, a RAM, etc., and a display means 101 for displaying the state of the processing operation and the image. In addition, it is connected to an input means 102 used when an operator registers machining content information and the like.

  The control unit 100 is an image processing unit that processes an image captured by the imaging unit 30. When the control unit 100 cuts each workpiece W, the control unit 100 forms a detection groove DD (shown in FIGS. 5 and 6) whose one end is a dead end in the workpiece W. The control means 100 causes the imaging means 30 to image one end DDa of the detection groove DD, and sets the length of the captured image SG (shown in FIG. 7) of the detection groove DD obtained by the imaging to one end DDa of the detection groove DD. The display means 101 displays an image KG (shown in FIG. 12) that is reduced to a length viewed from the tangential direction TD (shown in FIG. 10) of the circle formed by the outer periphery of the cutting blade 21 that forms To display.

  Next, the machining operation of the cutting device 1 according to the embodiment will be described. In the machining operation, the operator registers the machining content information in the control means 100, and the cutting device 1 starts the machining operation when the operator gives an instruction to start the machining operation. The machining content information includes the cutting depth d (shown in FIG. 10) of the cutting blade 21 from the upper surface Wa of the workpiece W when the end DDa forms the dead end detection groove DD, and the cutting blade 21. The radius R (shown in FIG. 10) and the amount of movement of the chuck table 10 by the X-axis moving means when forming the detection groove DD are included. First, when the operator stores the workpiece W before cutting in the cassette elevator 60 and receives an instruction to start the machining operation from the operator, the control unit 100 loads the workpiece W before cutting from the cassette elevator 60. The workpiece W taken out is sucked and held on the holding surface 10 a of the chuck table 10, and the annular frame F is clamped by the clamp portion 12.

  Next, the control means 100 moves the chuck table 10 below the cutting means 20 by the X-axis moving means, and is held by the chuck table 10 below the imaging means 30 fixed to the cutting means 20. The workpiece W is positioned and imaged by the imaging means 30. The imaging unit 30 outputs information on the captured image to the control unit 100. Then, the control means 100 executes image processing such as pattern matching for aligning the street S of the workpiece W held on the chuck table 10 with the cutting blade 21 of the cutting means 20, and the chuck table. The relative position between the workpiece W held by 10 and the cutting means 20 is adjusted.

  Then, the control means 100 moves the cutting blade 21 and the workpiece W along the street S by the X-axis movement means, the Y-axis movement means 40, the Z-axis movement means 50, and the rotational drive source based on the machining content information. The street S is cut by the cutting blade 21.

  When the control unit 100 cuts all the streets S and divides the workpiece W into the individual devices D, the chuck table 10 is retracted from below the cutting unit 20, and then the chuck table 10 is sucked and held and clamped. The holding of the part 12 is released. Then, the control means 100 transports the workpiece W after the cutting process to the cleaning means 70, cleans it with the cleaning means 70, and then accommodates it in the cassette elevator 60. The control means 100 places the workpiece W before cutting again on the chuck table 10 and repeats the above-described process to divide the workpiece W into individual devices D.

  Further, when the control means 100 cuts each workpiece W, one end DDa forms a dead end detection groove DD, and the captured image SG of the detection groove DD is reduced to an image KG viewed from the tangential direction TD. Then, a grasping method for grasping the outer peripheral shape (wear state) of the cutting blade 21 is executed. FIG. 3 is a flowchart of an example of a method for grasping the wear state of the outer periphery of the cutting blade of the cutting apparatus according to the embodiment. FIG. 4 is a cross-sectional view schematically showing a state in which the cutting means of the cutting apparatus according to the embodiment forms a detection groove. FIG. 5 is a perspective view showing a workpiece in which a detection groove is formed by the cutting means of the cutting apparatus according to the embodiment. 6 is an enlarged plan view showing a VI part in FIG. FIG. 7 is a diagram illustrating a captured image obtained by imaging the detection groove illustrated in FIG. 6. FIG. 8 is a view showing an image displayed on the display means by reducing the length of the captured image shown in FIG. FIG. 9 is a cross-sectional view of the outer periphery of the cutting blade in which the detection groove shown in FIG. 6 is formed. 10 is a view showing a longitudinal section in a direction parallel to the street of the detection groove shown in FIG.

  The control means 100 of the cutting device 1 according to the embodiment executes the flowchart shown in FIG. 3 when cutting each workpiece W. The control means 100 cuts the workpiece W over the entire length of each street S across the outer peripheral surplus area GR and the device area DR by cutting the cutting blade 21 to the center in the thickness direction of the dicing tape T. (Step ST1). After cutting the workpiece W over the entire length of each street S, the control means 100 determines whether or not a predetermined street S among a plurality of streets S has been cut (step ST2). When it is determined that the predetermined street S has been cut (step ST2: Yes), the control unit 100 forms a detection groove DD in a part of the workpiece W (step ST3). As the predetermined street S, a plurality of streets S from the start of processing can be used.

  The control means 100 forms the detection groove DD in the outer peripheral surplus region GR of the street S to be cut next to the predetermined street S. Specifically, the control means 100 controls the X-axis moving means and the Y-axis moving means 40 as shown by a dotted line in FIG. And the Z-axis moving means 50 is controlled so that the cutting blade 21 is positioned at a height at which the workpiece W is cut by the cutting depth d.

  The control unit 100 controls the X-axis moving unit to bring the chuck table 10 close to the cutting blade 21 along the street S and cut it into the outer peripheral surplus region GR, and the chuck table 10 is input from the input unit 102. Move the amount moved. Then, the control unit 100 controls the Z-axis moving unit 50 to raise the cutting blade 21. As shown in FIGS. 5 and 6, the control unit 100 of the cutting apparatus 1 cuts the outer peripheral surplus region GR that is a part of the workpiece W with the cutting blade 21, and the one end DDa on the device region DR side stops. The detection groove DD is formed. Note that one end DDa of the detection groove DD is formed so that the cutting blade 21 into which the workpiece W is cut is raised in the Z-axis direction, so that it gradually approaches the upper surface Wa as it approaches the device region DR. It is formed with a dead end. For this reason, the outer peripheral shape of the cutting blade 21 appears at one end DDa of the detection groove DD. That is, the shape of the one end DDa of the detection groove DD is equal to the shape of the outer periphery of the cutting blade 21.

  The control unit 100 controls the X-axis moving unit and the Y-axis moving unit 40 to position one end DDa of the detection groove DD below the imaging unit 30. The imaging means 30 images one end DDa of the detection groove DD where the one end DDa formed by cutting the outer peripheral surplus region GR is a dead end, and acquires the captured image SG shown in FIG. 7 (step ST4).

  The control means 100 is configured so that the length of at least a part of the image including the one end DDa of the detection groove DD of the captured image SG is the length viewed from the tangential direction TD of the circle formed by the outer periphery of the cutting blade 21. The length of at least a part of the image is reduced, and an image KG that approximates the outer peripheral shape of the cutting blade 21 is formed (step ST5). Specifically, as shown in FIG. 7, the control unit 100 divides the captured image SG in the longitudinal direction of the detection groove DD. In the embodiment, the control unit 100 divides the captured image SG into a plurality of divided images BG for each length L that can be obtained from the one end DDa of the detection groove DD by the following Expression 1. The control means 100 stores the following formula 1 in advance. The control means 100 determines the length of a divided image BG (hereinafter denoted by reference sign BG2) including one end DDa of the detection groove DD that can be obtained by Expression 1 corresponding to the value α1 (indicated by α in Expression 1). L1 (indicated by L in Equation 1) is obtained. However, the value α1 is, for example, 1 μm, R is the radius of the cutting blade 21, and d is the cutting depth of the detection groove DD. The divided image BG2 corresponds to a part of the image including the one end DDa of the detection groove DD.

  The control unit 100 removes a part of the pixels constituting the divided image BG2 so that the length L (L1) of the divided image BG2 becomes the value α1. At this time, the control means 100 removes pixels at equal intervals for each interval according to the difference in length between the length L (L1) and the value α1.

  Next, the control means 100 determines the length L (L2) of the divided image BG adjacent to the divided image BG2 (hereinafter referred to as symbol BG3) corresponding to the value α2 (indicated by α in Equation 1). The value α2 is 1 μm, for example, d is the depth of cut of the detection groove DD, and R is R−α1. The control unit 100 removes a part of the pixels constituting the divided image BG3 so that the length L (L2) of the divided image BG3 becomes the value α2. Further, the control means 100 determines the length of the divided image BG (hereinafter, indicated by reference sign BG4) on the outer periphery side of the workpiece W adjacent to the divided image BG3 corresponding to the value α3 (indicated by α in Equation 1). The length L (L3) is obtained by using Equation 1 where the value α3 is 1 μm, for example, d is the cutting depth of the detection groove DD, and R is R− (α1 + α2). The control unit 100 removes a part of the pixels constituting the divided image BG3 so that the length L (L3) of the divided image BG4 becomes the value α3.

  Thus, the control means 100 determines the lengths L1, L2, L3,..., LN of the divided images BG2, BG3, BG4..., BGN corresponding to the values α1, α2, α3,. The captured image SG is divided into divided images BG1, BG2, BG3,..., BGN. The control means 100 removes some of the pixels of all the divided images BG2, BG3, BG4,..., BGN, and reduces the length to values α1, α2, α3,. Then, the control means 100 combines the reduced divided images BG1, BG2, BG3, BG4,..., BGN to reduce the length of the captured image SG as shown in FIG. An image KG that approximates the outer peripheral shape is formed, and the formed image KG is displayed on the display means 101. The shape of the detection groove DD in the image KG shown in FIG. 8 is substantially equal to the cross-sectional shape of the outer periphery of the cutting blade 21 in which the detection groove DD shown in FIG. 9 is formed.

  Then, after determining that the predetermined street S has not been cut (step ST2: No) or after displaying the image KG on the display unit 101, the control unit 100 has cut all the streets S. Is determined (step ST6), and when it is determined that all the streets S are not cut (step ST6: No), the process returns to step ST1. When it is determined that all the streets S have been cut (step ST6: Yes), the control unit 100 ends the flowchart shown in FIG.

  Next, Equation 1 described above will be described. As shown in FIG. 10, the imaging means 30 images one end DDa of the detection groove DD from above, which is orthogonal to the upper surface Wa of the workpiece W. 10, the center of the cutting blade 21 when one end DDa of the detection groove DD is formed is A, and the point extending from the center A in the Z-axis direction and intersecting the upper surface Wa of the workpiece W is B. When one end DDa of the groove DD is C0, the length of the side BC0 of the triangle ABC0 can be expressed by the following Expression 2.

  In FIG. 10, the end of the divided image BG2 away from the one end DDa of the detection groove DD is C1, and the radial direction of the cutting blade 21 at the end C1 of the divided image BG2 away from the one end DDa of the detection groove DD. If the depth of the detection groove DD is α1 (indicated by α in Equation 3), the length of the side BC1 of the triangle ABC1 can be expressed by Equation 3 below.

  In FIG. 10, the control unit 100 obtains Expression 1 from Expression 2 and Expression 3 when the length in the longitudinal direction of the detection groove DD of the divided image BG2 is L1 (indicated by L in Expression 1). be able to. The control means 100 sets the value α1, which is the depth of the detection groove DD, to 1 μm, and the radius R of the cutting blade 21 and the cutting depth d of the detection groove DD are determined in advance. The length L1 in the longitudinal direction of the groove DD can be obtained. Then, the control means 100 can obtain the length L2 in the longitudinal direction of the detection groove DD of the divided image BG3 by setting the value α2 to 1 μm and R to R−α1 in the equation 1, and the value α3. By setting 1 μm and R as R− (α1 + α2), the length L3 in the longitudinal direction of the detection groove DD of the divided image BG4 can be obtained. Similarly, the control means 100 can obtain the lengths L1, L2, L3,..., LN of all the divided images BG2, BG3, BG4,. By reducing the lengths L1, L2, L3,..., LN of the divided images BG2, BG3, BG4,..., BGN of the captured image SG to values α1, α2, α3,. Each of the divided images BG2, BG2, BG4,..., BGN has a length as viewed from the tangential direction TD of the circle formed by the outer periphery of the cutting blade 21. BG3, BG4,..., BGN are reduced in length. The control unit 100 combines the reduced divided images BG2, BG3, BG4,..., BGN so that the length of the detection groove DD of the captured image SG is equal to the outer circumference of the cutting blade 21 at one end DDa of the detection groove DD. The length of the captured image SG is reduced so that the length is viewed from the tangential direction TD of the circle formed by. For this purpose, an image KG approximating the outer peripheral shape of the cutting blade 21 is obtained from the imaging means 30 (shown by a dotted line in FIG. 10) arranged on the tangential direction TD of the cutting blade 21 at one end DDa of the detection groove DD. This approximates an image obtained by imaging one end DDa of the detection groove DD.

  As described above, according to the cutting device 1 according to the embodiment, the captured image SG obtained by imaging the one end DDa of the detection groove DD has a length as viewed from the tangential direction TD of the cutting blade 21. The image KG that approximates the outer peripheral shape of the cutting blade 21 is reduced. For this reason, the cutting apparatus 1 can easily grasp the cross-sectional shape of the outer periphery of the cutting blade 21 by visually recognizing the approximate image KG displayed on the display unit 101. Therefore, the cutting device 1 can grasp the replacement time and dressing time of the cutting blade 21.

  Moreover, according to the cutting device 1 which concerns on embodiment, based on value (alpha) 1, (alpha) 2, (alpha) 3, ..., (alpha) N and Formula 1, captured image SG is divided into several division image BG1, BG2, BG3, BG4, ... .., divided into BGN and reduced the lengths L1, L2, L3,..., LN of the divided images BG2, BG3, BG4,. To do. For this reason, the cutting apparatus 1 can bring the image KG that approximates the outer peripheral shape of the cutting blade 21 close to the cross-sectional shape of the cutting blade 21. Therefore, the cutting device 1 can easily grasp the cross-sectional shape of the outer periphery of the cutting blade 21.

  Furthermore, since the cutting device 1 according to the embodiment forms the detection groove DD in the street S of the outer peripheral surplus region GR, the influence on the device D can be suppressed.

[Modification 1]
The cutting device which concerns on the modification 1 of embodiment of this invention is demonstrated based on drawing. FIG. 11 is a diagram illustrating a captured image obtained by imaging by the imaging unit of the cutting apparatus according to the first modification of the embodiment. FIG. 12 is a diagram illustrating an image displayed on the display unit by reducing the length of the divided image of the captured image illustrated in FIG. 11. In FIG. 11 and FIG. 12, the same parts as those in the embodiment are denoted by the same reference numerals, and description thereof is omitted.

  The control means 100 of the cutting device 1 according to the first modification of the embodiment includes one end of the detection groove DD without dividing the captured image SG of FIG. 11 into a plurality of divided images BG1, BG2, BG3,. Only the divided image BG1 including DDa is extracted from the captured image SG, and the length is reduced as shown in FIG. 12 based on the value α1 and Expression 1 described above, and displayed on the display unit 101.

  According to the cutting device 1 according to the first modification of the embodiment, by visually recognizing the approximate image KG displayed on the display unit 101, it becomes easy to grasp the cross-sectional shape of the outer periphery of the cutting blade 21. The exchange time and dressing time can be grasped. Further, the cutting device 1 according to the first modification of the embodiment reduces only the divided image BG1 including the one end DDa of the detection groove DD and displays it on the display unit 101. Therefore, the display is performed after the detection groove DD is formed. The time required for displaying on the means 101 can be suppressed.

[Modification 2]
The cutting device which concerns on the modification 2 of embodiment of this invention is demonstrated based on drawing. FIG. 13 is a cross-sectional view schematically showing a state in which the cutting means of the cutting apparatus according to the second modification of the embodiment forms a detection groove. In FIG. 13, the same parts as those of the embodiment are denoted by the same reference numerals and the description thereof is omitted.

  The cutting device 1 according to the second modification of the embodiment forms the detection groove DD in the street S. As shown in FIG. 13, the cutting device 1 according to the second modification of the embodiment positions the cutting blade 21 above the street S in the device region DR, and then controls only the Z-axis moving unit 50 to cut the cutting blade. 21 is lowered, and the cutting depth 21 is cut into the street S, and then the cutting blade 21 is raised. The cutting device 1 according to the second modification of the embodiment forms a detection amount groove DD whose both ends are dead ends.

  According to the cutting device 1 according to the second modification of the embodiment, the cross-sectional shape of the outer periphery of the cutting blade 21 can be easily grasped by visually recognizing the approximate image KG displayed on the display unit 101 as in the embodiment. Thus, it is possible to grasp the replacement time of the cutting blade 21 and the dressing time.

[Modification 3]
A cutting apparatus according to Modification 3 of the embodiment of the present invention will be described with reference to the drawings. FIG. 14 is a view showing a longitudinal section in a direction parallel to the street of the detection groove formed by the cutting means of the cutting apparatus according to the third modification of the embodiment. In FIG. 14, the same parts as those in the embodiment are denoted by the same reference numerals and description thereof is omitted.

  In the cutting device 1 according to the second modification of the embodiment, when the control unit 100 divides the captured image SG into a plurality of divided images BG1, BG2, BG3,..., BGN, around the rotation center of the cutting blade 21. The captured image SG is divided for each equal angle a.

  According to the cutting device 1 according to the third modification of the embodiment, as in the embodiment, it is easy to grasp the cross-sectional shape of the outer periphery of the cutting blade 21 by visually recognizing the approximate image KG displayed on the display unit 101. Thus, it is possible to grasp the replacement time of the cutting blade 21 and the dressing time.

〔Example〕
Next, the inventors of the present invention confirmed the effect of the cutting device described in the embodiment. In the confirmation, a detection groove DD having a cutting depth d of 300 μm was formed in the workpiece W using a cutting blade 21 having an outer diameter of 55 mm and a thickness of 0.05 mm. FIG. 15 is a captured image obtained by imaging one end of the detection groove DD formed in the workpiece of the example. FIG. 16 is an image obtained by reducing the captured image shown in FIG. FIG. 17 shows a cross-sectional shape of the detection groove shown in FIG.

  Since the image shown in FIG. 16 and the image shown in FIG. 17 are very similar, according to the cutting apparatus of the present invention, it becomes easy to grasp the cross-sectional shape of the outer periphery of the cutting blade 21, and the replacement time of the cutting blade 21 It became clear that it was possible to grasp the dressing time.

  In the present invention, the control means 100 forms an image KG that approximates the outer peripheral shape of the cutting blade 21, and then pattern-matches this image KG with the image of the cross-sectional shape of the non-defective cutting blade 21, for example, When the correlation value falls below a predetermined value, a notification may be given to prompt the operator to replace the cutting blade 21 or to dress.

  In the embodiment, the captured image SG is divided into a plurality of divided images BG1, BG2, BG3,..., BGN, and the lengths of the divided images BG2, BG3, BG4,. However, in the present invention, the length of the divided image BG2, which is at least a part of the image including the one end DDa of the detection groove DD of the captured image SG, may be reduced to a length viewed from the tangential direction TD.

  The present invention is not limited to the above embodiment. That is, various modifications can be made without departing from the scope of the present invention.

DESCRIPTION OF SYMBOLS 1 Cutting device 10 Chuck table 10a Holding surface 20 Cutting means 21 Cutting blade 30 Imaging means 100 Control means (image processing means)
W Workpiece DD Detection groove DDa One end SG Captured image BG Split image BG2 Split image (partial image)
KG Approximate image

Claims (4)

A chuck table for holding a workpiece on a holding surface, a cutting means for cutting the workpiece held on the chuck table with a cutting blade, and a direction perpendicular to the holding surface for the workpiece held on the chuck table A cutting apparatus comprising: an imaging unit that captures an image from an image processing unit that processes an image captured by the imaging unit;
The imaging means
One end formed by cutting a part of the workpiece with a cutting blade is a dead end detection groove, and the one end where the outer peripheral shape of the cutting blade appears is captured to obtain a captured image,
The image processing means includes:
The length of the at least part of the image so that the length of at least a part of the image including one end of the detection groove of the captured image is a length viewed from the tangential direction of the circle formed by the outer periphery of the cutting blade. Reduce the depth, form an image that approximates the outer shape of the cutting blade ,
A cutting device comprising display means for displaying the image . The image processing means includes:
The captured image is divided into a plurality of divided images in the longitudinal direction of the detection groove, and the length in the longitudinal direction of the detection groove in the divided image is the length viewed from the tangential direction of the cutting blade. The cutting apparatus according to claim 1, wherein the image that approximates the outer peripheral shape of the cutting blade is formed by reducing the length of the divided image in the longitudinal direction .   The image processing means performs pattern matching between the image and a cross-sectional image of a non-defective cutting blade, and notifies when the correlation value is lower than a predetermined value. Cutting equipment.   The image processing means includes:
  Let the radius of the cutting blade be R,
  The cutting depth of the cutting blade is d,
  The maximum depth of the divided image including one end of the detection groove when viewed from the tangential direction of the detection groove is α,
  The length L in the longitudinal direction of the detection groove of the divided image is
  L = ((R ² -(R-d) ² ) ^1/2 -((R-α) ² -(R-d) ² ) ^1/2
  And using
  When calculating the length L in the longitudinal direction of the detection groove of each divided image,
  When each divided image is nth from the divided images including one end of the detection groove, R = R−n × α is calculated,
  The peripheral shape of the cutting blade is reduced by removing the pixels of each divided image and reducing the length of the divided image in the longitudinal direction so that the length L in the longitudinal direction of each divided image is α. The cutting apparatus according to claim 2, wherein the image that approximates to is formed.