Blade diagnosis method and blade diagnosis device

Abstract

To provide a blade diagnosis method and a blade diagnosis device capable of accurately diagnosing a blade.SOLUTION: Groove machining for forming a groove (kerfs 86 and 87) on a surface of an object to be cut (calibration work CW) by a disc-like blade 21 includes: a groove forming process that can be executed a plurality of times with different cutting depths of the blade 21 (a blade rotation control part 70 and a movement control part 72); a captured image acquisition process for acquiring a captured image of the groove in plan view for each groove formed by a plurality of times of groove machining (a microscope 23, an imaging control part 74, etc.); a dimension measurement process for measuring a dimension of the groove for each groove on the basis of the captured image of each groove (a dimension measurement part 78); and a calculation process for calculating a radius of the blade on the basis of a result of the formation of a plurality of grooves of different cutting depths of the blade in the groove forming process, and a measurement result of dimensions of a plurality of grooves of different depths in the dimension measurement process (calculation part 80).SELECTED DRAWING: Figure 9

Description

[Technical field]

[0001] The present invention relates to a blade diagnostic method and a blade diagnostic device for diagnosing a blade. [Background technology]

[0002] Dicing machines are known that cut (dices) workpieces such as wafers using a disk-shaped blade rotated at high speed by a spindle. It is known that the cutting depth of the blade when cutting the workpiece affects the cutting quality, and in recent years, some dicing machines in particular can control the cutting height of the blade to the order of 1 μm.

[0003] In a dicing machine, if the tip of the blade becomes abnormally worn, the cutting quality deteriorates, and there is a risk of affecting chipping, especially on the back side. Therefore, if abnormal wear of the blade tip shape (tip shape) can be detected in advance, it becomes possible to take measures such as issuing an error, dressing the blade, or replacing the blade. As a result, the wafer can be cut using a blade with a good tip shape. Therefore, it is important to accurately measure the blade radius (outer diameter) and tip shape, and diagnose the blade based on these measurement results.

[0004] Patent Document 1 describes a method for measuring and managing the amount of wear in the tip shape of a blade using an optical or contact type cutter set.

[0005] Patent document 2 describes a blade diagnosis method that includes the steps of forming a detection groove on part of the surface of a product workpiece using a blade, photographing this detection groove, detecting the tip shape of the blade based on the photographed image of the detection groove, and comparing the detected tip shape of the blade with the tip shape of a new blade to determine whether the blade needs to be replaced.

[0006] Patent Document 3 describes a blade diagnostic method including the steps of chop-cutting the surface of a product workpiece with a blade, photographing a groove formed on the surface of the product workpiece by chop-cutting, measuring the dimensions of the groove based on the photographed image of the groove, and calculating the blade tip shape based on the measurement results of the groove dimensions, etc. In this step of calculating the blade tip shape, the blade tip shape is calculated based on the measurement results of the groove dimensions, a known blade radius, and a known surface height of the product workpiece (necessary to determine the cutting depth). [Prior art documents] [Patent documents]

[0007] [Patent Document 1] JP 2003-234309 A [Patent Document 2] JP 2010-240776 A [Patent Document 3] JP 2017-164843 A Summary of the Invention [Problem to be solved by the invention]

[0008] However, the blade diagnostic method using an optical or contact type cutter set described in Patent Document 1 cannot measure the tip shape (cross-sectional shape) and wear state of the blade, nor can it measure the radius of the blade.

[0009] In the blade diagnosis method described in Patent Document 2, the tip shape of the blade is detected based on a captured image of the detection groove, but on the product workpiece, the visibility of the detection groove (cutting mark) changes depending on the structures in the street, the state of the workpiece surface film, cutting conditions, etc. In addition, the shape of the tip of the detection groove itself may not be stable due to the influence of chipping, etc. For this reason, the blade diagnosis method described in Patent Document 2 cannot detect the accurate wear state of the tip shape of the blade. Furthermore, the blade diagnosis method described in Patent Document 2 cannot detect the radius of the blade.

[0010] The blade diagnostic method described in Patent Document 3 requires accurate measurement of the blade radius and the surface height of the product workpiece in advance or a mechanism for accurate measurement (such as an air microscope), and if the blade radius and the surface height (thickness) of the product workpiece are unknown, the blade tip shape cannot be measured. Also, if the blade radius and the surface height of the product workpiece are not accurately measured in advance, the measurement error of the blade tip shape will be large.

[0011] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a blade diagnosis method and a blade diagnosis device capable of accurately diagnosing a blade. [Means for solving the problem]

[0012] A blade diagnosis method for achieving the object of the present invention includes a groove forming step in which a disk-shaped blade is rotated while cutting the surface of a flat workpiece with the tip of the blade to form grooves on the surface multiple times at different blade cutting depth positions; an image acquisition step in which a photographed image of the groove in a planar view is acquired for each groove formed by the multiple groove processing operations; a dimension measurement step in which the dimensions of each groove are measured based on the photographed images of each groove acquired in the image acquisition step; and a calculation step in which the radius and tip shape of the blade are calculated based on the measurement results of the dimensions of each groove obtained in the dimension measurement step.

[0013] According to this blade diagnosis method, even if the surface height and cutting depth (thickness, surface height) of the workpiece are unknown, the radius and tip shape of the blade can be accurately calculated.

[0014] In a blade diagnostic method according to another aspect of the present invention, the calculation step calculates the cutting depth of the blade in any one of a plurality of groove cutting operations based on the measurement results of the groove dimensions formed in the groove cutting operation and the calculation result of the blade radius, thereby making it possible to accurately calculate the cutting depth even if the surface height of the workpiece, etc., is unknown.

[0015] In a blade diagnosis method according to another aspect of the present invention, the photographed image acquiring step acquires, for each groove, a photographed image including at least one of both ends of the groove.

[0016] In a blade diagnostic method according to another aspect of the present invention, a groove forming step performs groove machining multiple times on a workpiece placed on a sub-table that is different from the cutting table on which the product workpiece is placed. This allows the kerf to be measured in a stable environment, regardless of the visibility of the product workpiece, and also eliminates the effects of the cutting characteristics of the product workpiece, such as chipping, so that the blade tip shape can be accurately calculated.

[0017] In a blade diagnostic method according to another aspect of the present invention, the groove forming step performs groove machining a plurality of times at different cutting depths in the same position on the surface of the workpiece, and the cutting depth is made deeper each time the groove machining is performed, thereby reducing the amount of the workpiece used.

[0018] In a blade diagnostic method according to another aspect of the present invention, the groove forming step performs groove machining a plurality of times with different cutting depths at different positions on the surface of the workpiece.

[0019] A blade diagnosis device for achieving the object of the present invention comprises a rotational drive unit that rotates a disk-shaped blade, a relative movement unit that moves the blade relative to a flat workpiece, a groove formation control unit that controls the rotational drive unit and the relative movement unit to perform groove processing multiple times at different blade cutting depth positions by cutting the surface of the flat workpiece with the tip of the rotating blade to form grooves on the surface, an image acquisition unit that acquires photographed images of the grooves in a planar view for each groove formed by the multiple groove processing operations, a dimension measurement unit that measures the dimensions of each groove based on the photographed images of each groove acquired by the image acquisition unit, and a calculation unit that calculates the radius and tip shape of the blade based on the measurement results of the dimensions of each groove by the dimension measurement unit.

[0020] In another aspect of the blade diagnosis device of the present invention, a calculation unit calculates the cutting depth in any one of multiple groove machining operations based on the measurement results of the dimensions of the groove formed in that operation and the calculation results of the blade radius. Effect of the Invention

[0021] The present invention allows for accurate diagnosis of the blade. [Brief description of the drawings]

[0022] [Figure 1] FIG. 2 is a perspective view of a dicing device that cuts a workpiece. [Diagram 2] FIG. [Diagram 3] 3 is an enlarged perspective view of a rotation unit and a sub-table in FIG. 2. [Figure 4] FIG. 2 is a functional block diagram of an overall control unit of the dicing device. [Diagram 5] FIG. 11 is an explanatory diagram for explaining a first chop cut on a calibration workpiece. [Figure 6] FIG. 11 is an explanatory diagram for explaining a second chop cut on the calibration workpiece. [Figure 7] FIG. 2 is an explanatory diagram for explaining photographing of a kerf by a microscope 23. [Figure 8] FIG. 13 is an explanatory diagram for explaining measurement of a kerf dimension by a dimension measuring unit. [Figure 9] FIG. 11 is an explanatory diagram for explaining the calculation of the blade radius and the first cutting depth by a calculation unit. [Figure 10] 11 is an explanatory diagram for explaining the calculation of the radius and the cutting depth at each position in the width direction of the blade by the calculation unit. FIG. [Figure 11] 11 is an explanatory diagram for explaining the calculation of the actual tip shape of the blade by a calculation unit. FIG. [Figure 12] 10 is a flowchart showing the flow of a blade diagnosis process performed by the dicing device. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0023] [Dicing equipment configuration] 1 is a perspective view of a dicing device 10 that cuts a workpiece W (product workpiece) such as a semiconductor wafer. Note that the X, Y and Z axes in the figure are mutually perpendicular axes, the X and Y axes are axes parallel to the horizontal direction, and the Z axis is an axis perpendicular to the horizontal direction.

[0024] The dicing apparatus 10 includes a load port 12, a transport mechanism 14, a processing unit 16, and a cleaning unit 18. A cassette containing a large number of workpieces W mounted on a frame F is placed on the load port 12. The transport mechanism 14 transports the workpieces W. The processing unit 16 performs dicing processing on the workpieces W. The cleaning unit 18 spin-cleans the workpieces W that have already been cut. Inside the housing 10A of the dicing apparatus 10, there is provided a general control unit 60 (see FIG. 4) that controls the operation of each unit of the dicing apparatus 10. The general control unit 60 may be provided outside the housing 10A.

[0025] The unmachined workpiece W stored in a cassette placed on the load port 12 is transported by the transport mechanism 14 to the processing section 16, where it is subjected to cutting such as cutting or grooving in order to divide it into individual chips. The workpiece W that has been processed by the processing section 16 is then transported by the transport mechanism 14 to the cleaning section 18, where it is cleaned, and then transported by the transport mechanism 14 to the load port 12 and stored in a cassette.

[0026] Fig. 2 is an external perspective view of the processing unit 16. As shown in Fig. 2 and the above-described Fig. 1, the processing unit 16 includes a pair of disk-shaped blades 21, a blade cover (not shown), a pair of spindles 22, a pair of microscopes 23, and a cutting table 31 for holding a workpiece.

[0027] The pair of blades 21 are disposed opposite to each other in the Y-axis direction, and are each held by a spindle 22 so as to be rotatable about a blade rotation axis parallel to the Y-axis direction. The pair of spindles 22 correspond to the rotation drive unit of the present invention. The pair of spindles 22 each have a built-in high-frequency motor, and rotate the blade 21 at high speed about the blade rotation axis.

[0028] The microscope 23 constitutes a part of the photographic image acquisition unit of the present invention, and one microscope 23 is provided near each spindle 22. Although not shown, the microscope 23 has a photographic optical system and an image sensor. The microscope 23 may be composed of a high-magnification microscope and a low-magnification microscope with different photographic magnifications. In addition, in order to prevent the drawing from becoming complicated, FIG. 2 shows only the microscope 23 provided near one of the two spindles 22, and does not show the microscope 23 provided near the other one.

[0029] The microscope 23 photographs the surface of the workpiece W when cutting the workpiece W. The microscope 23 also photographs the surface of the calibration workpiece CW when diagnosing the blade 21, which will be described later.

[0030] Furthermore, each spindle 22 and each microscope 23 are held so as to be freely movable in the Y-axis direction and the Z-axis direction via a Y-carriage 43 and a Z-carriage 44, which will be described later.

[0031] The cutting table 31 adsorbs and holds the workpiece W on its upper surface. The cutting table 31 is held by an X-carriage 36 (described later) so as to be movable in the X-axis direction, and is held by a rotation unit 37 (described later) so as to be rotatable.

[0032] Processing section 16 is provided with an X base 32, an X guide 34, an X drive section 35, an X carriage 36, and a rotation unit 37. X base 32 has a flat plate shape extending in the X-axis direction, and an X guide 34 is provided on its upper surface in the Z-axis direction. X guide 34 has a shape extending in the X-axis direction, and guides X carriage 36 along the X-axis direction. X drive section 35 uses, for example, a linear motor or the like, and moves (drives) X carriage 36 in the X-axis direction along X guide 34.

[0033] The rotation unit 37 is provided on the upper surface of the X-carriage 36. The cutting table 31 is provided on the upper surface of the rotation unit 37. The rotation unit 37 includes a rotation drive unit (not shown) that is configured with a motor, gears, etc., and rotates the cutting table 31 about its rotation axis.

[0034] The workpiece W transported from the load port 12 by the transport mechanism 14 is attracted and held by the cutting table 31, and moves and rotates integrally with the cutting table 31. As a result, the workpiece W is rotated during alignment before cutting, and the workpiece W is fed for cutting in the X direction during cutting, via the cutting table 31, etc.

[0035] Fig. 3 is an enlarged perspective view of the rotation unit 37 and the sub-table 38 in Fig. 2. As shown in Fig. 3, the rotation unit 37 holds (non-rotatably holds) the sub-table 38 at a shift position in the horizontal direction (X direction in this embodiment) from the cutting table 31.

[0036] The sub-table 38 adsorbs and holds a flat calibration workpiece CW on its upper surface. The calibration workpiece CW corresponds to the workpiece of the present invention, and for example, a mirror workpiece (also called a mirror wafer) is used. This calibration workpiece CW is chop-cut (also called chopping, which corresponds to groove machining of the present invention) twice with different cutting depths by the same blade 21 during diagnosis of the blade 21, which will be described later.

[0037] Processing unit 16 is also provided with a Y base 41, a Y guide 42, a pair of Y carriages 43, and a pair of Z carriages 44. Y base 41 has a gate-like shape that straddles X base 32 in the Y-axis direction. Y guide 42 is provided on a side surface of this Y base 41 in the X-axis direction. Y guide 42 has a shape that extends in the Y-axis direction, and guides each of the pair of Y carriages 43 along the Y-axis direction. The pair of Y carriages 43 are driven independently along Y guide 42 by Y drive unit 46 (see FIG. 4) that is composed of a stepping motor, a ball screw, etc.

[0038] A Z carriage 44 is provided on each of the pair of Y carriages 43 so as to be movable in the Z axis direction via a Z drive unit 48 (see FIG. 4) constituted by a stepping motor or the like. The above-mentioned spindle 22 is attached to each Z carriage 44.

[0039] When cutting the workpiece W, the blade 21 is indexed in the Y-axis direction and cut in the Z-axis direction relative to the workpiece W that is sucked and held on the cutting table 31. When diagnosing the blade 21, which will be described later, the blade 21 chops and cuts a calibration workpiece CW that is sucked and held on the sub-table 38.

[0040] Although two sets of the spindle 22, microscope 23, Y carriage 43, and Z carriage 44 are provided facing each other on the left and right, they have the same configuration and function, so the following description will focus on only one of them.

[0041] The dicing device 10 has a function of measuring the radius and tip shape of the blade 21, and diagnosing the blade 21 based on these measurement results (hereinafter, simply referred to as diagnosing the blade 21). As will be described in detail later, the dicing device 10 performs chop cuts of the calibration workpiece CW with the blade 21 twice at fixed or regular timing with different cutting depths. The dicing device 10 also photographs, with the microscope 23, kerfs 86, 87 (see FIG. 6) formed in the calibration workpiece CW by each chop cut. The dicing device 10 then analyzes the photographed image data 88 (see FIG. 4) for each of the kerfs 86, 87 to perform the above-mentioned diagnosis of the blade 21. Thus, the dicing device 10 functions as the blade diagnosis device of the present invention.

[0042] [Functions of the central control unit] Fig. 4 is a functional block diagram of the overall control unit 60 of the dicing apparatus 10. Of the multiple functions of the overall control unit 60, Fig. 4 illustrates only the functions relating to the diagnosis of the blade 21, and the functions relating to other controls of the dicing apparatus 10, such as cutting the workpiece W, are not illustrated because they are publicly known techniques.

[0043] 4, the general control unit 60 includes an arithmetic circuit including various processors and memories. The various processors include a central processing unit (CPU), a graphics processing unit (GPU), an application specific integrated circuit (ASIC), and a programmable logic device (e.g., simple programmable logic devices (SPLD), complex programmable logic devices (CPLD), and field programmable gate arrays (FPGA)). The various functions of the general control unit 60 may be realized by one processor or by multiple processors of the same or different types.

[0044] In addition to the microscope 23, X drive unit 35, Y drive unit 46, and Z drive unit 48 already described, an operation unit 62, a storage unit 64, a display unit 66, and the like are connected to the general control unit 60.

[0045] The operation unit 62 receives various operations by an operator using a keyboard, a mouse, an operation panel, operation buttons, etc. For example, the operation unit 62 receives an operation to start diagnosis of the blade 21 (an operation to start chopping).

[0046] The storage unit 64 stores a control program (not shown) for the dicing apparatus 10. The storage unit 64 also stores the measurement results of the radius and tip shape of the blade 21, and the diagnosis results of the blade 21. The storage unit 64 also stores relative position information (not shown) indicating the relative positional relationship between the rotation unit 37 and the sub-table 38, and also stores in advance relative position information (not shown) indicating the relative positional relationship between the blade 21 and the optical axis (center of the field of view) of the microscope 23.

[0047] Various known monitors such as a liquid crystal display are used as the display unit 66. When diagnosing the blade 21, the display unit 66 displays the diagnosis results of the blade 21 (including the radius and tip shape of the blade 21) under the control of the general control unit 60.

[0048] The overall control unit 60 executes a control program (not shown) stored in the memory unit 64, and functions as a blade rotation control unit 70, a movement control unit 72, an imaging control unit 74, an image acquisition unit 76, a dimension measurement unit 78, a calculation unit 80, and a diagnosis unit 82 when diagnosing the blade 21.

[0049] The blade rotation control unit 70 controls the rotational drive of the blade 21 by the spindle 22 .

[0050] The movement control unit 72 controls the driving of the X drive unit 35, the Y drive unit 46, and the Z drive unit 48, which correspond to the relative movement units of the present invention, thereby controlling the relative movement of the blade 21 and the microscope 23 in the horizontal direction (X-axis direction and Y-axis direction) and the vertical direction (Z-axis direction) relative to the calibration work CW.

[0051] The photographing control unit 74 controls photographing by the microscope 23. The image acquiring unit 76 functions as an image input interface that acquires photographed image data 88 output from the microscope 23.

[0052] The dimension measuring unit 78 , the calculation unit 80 , and the diagnosis unit 82 execute calculation processing related to the diagnosis of the blade 21 based on the captured image data 88 output from the microscope 23 .

[0053] <Chop Cut> Fig. 5 is an explanatory diagram for explaining the first chop cut for the calibration workpiece CW. Fig. 6 is an explanatory diagram for explaining the second chop cut for the calibration workpiece CW. In Fig. 5 and Fig. 6, reference numerals 5A and 6A indicate side views of the calibration workpiece CW, etc., and reference numerals 5B and 6B indicate top views of the calibration workpiece CW after the chop cut.

[0054] As shown in Figure 5 and the above-mentioned Figure 4, the blade rotation control unit 70 and the movement control unit 72 function as a groove formation control unit of the present invention, and control the execution of chop cuts of the calibration work CW by the blade 21, more specifically, the execution of two chop cuts with different cutting depths.

[0055] When the blade rotation control unit 70 and the movement control unit 72 receive an operation to start diagnosis of the blade 21 through the operation unit 62, they control the driving of each unit to execute a first chop cut.

[0056] First, the movement control unit 72 drives the X drive unit 35 and the Y drive unit 46 to align the blade 21 in the X-axis direction and the Y-axis direction with the calibration workpiece CW on the sub-table 38. Note that the position at which the surface of the calibration workpiece CW is chopped is not strictly determined, so in the above-mentioned alignment, it is sufficient to relatively move the blade 21 to a position facing the surface of the calibration workpiece CW.

[0057] For example, the movement control unit 72 aligns the sub-table 38 (calibration workpiece CW) with the blade 21 in the X-axis direction by driving the X drive unit 35 to move the X carriage 36 (rotation unit 37) to a predetermined position in the X-axis direction. The movement control unit 72 also aligns the sub-table 38 (calibration workpiece CW) with the blade 21 in the Y-axis direction by driving the Y drive unit 46 to move the blade 21 to a predetermined position in the Y-axis direction. As a result, the blade 21 is set at a position facing the surface of the calibration workpiece CW.

[0058] Next, the blade rotation control unit 70 drives the spindle 22 to rotate the blade 21, and the movement control unit 72 drives the Z drive unit 48 to lower the Z carriage 44 and the blade 21 in the Z axis direction. As a result, the rotating blade 21 comes into contact perpendicularly with the surface of the calibration workpiece CW, and the blade 21 cuts the surface of the calibration workpiece CW.

[0059] Then, the movement control unit 72 continues to drive the Z drive unit 48 to lower the blade 21 to a lowered position that is determined in advance based on the position of the sub-table 38 in the Z axis direction and the thickness of the calibration work CW, etc., so that the blade 21 does not penetrate the calibration work CW, and then raises the blade 21 in the Z axis direction. During this time, the movement control unit 72 does not perform relative movement between the blade 21 and the calibration work CW in the X axis direction and the Y axis direction. As a result, the blade 21 cuts into the surface of the calibration work CW to a cutting depth C. inThe calibration workpiece CW is chopped at a depth of 100°, and a first kerf 86, which corresponds to a groove of the present invention, is formed on the surface of the calibration workpiece CW. in The value of is calculated by the calculation unit 80, which will be described later. This completes the first chop cut.

[0060] As shown in FIG. 6, after the measurement of the dimensions of the kerf 86 is completed, the blade rotation control unit 70 and the movement control unit 72 control the driving of each unit to perform a second chop cut, as will be described in detail later.

[0061] First, the movement control unit 72 drives at least one of the X drive unit 35 and the Y drive unit 46 to align the blade 21 in the X-axis direction and the Y-axis direction with the non-cutting area (area where the kerf 86 is not formed) on the surface of the calibration workpiece CW. Note that the position where the second chop cut is performed on the surface of the calibration workpiece CW is set to an area that does not overlap with the kerf 86 in this embodiment.

[0062] Next, similarly to the first chop cut, the blade rotation control unit 70 drives the spindle 22 to rotate the blade 21, and the movement control unit 72 drives the Z drive unit 48 to lower the Z carriage 44 (blade 21) in the Z axis direction. This causes the blade 21 to cut the non-cut area on the surface of the calibration workpiece CW.

[0063] Then, the movement control unit 72 continues to drive the Z drive unit 48 to lower the blade 21 to a second lowering position that is predetermined based on the thickness of the calibration workpiece CW, etc., and then raises the blade 21 in the Z-axis direction. The lowering position for this second chop cut is not particularly limited as long as it is a lowering position different from that for the first chop cut, and in this embodiment, it is, for example, a position lower than the first lowering position by the difference "dc". As a result, the blade 21 cuts into the surface of the calibration workpiece CW to a cutting depth "C in+dc" to form a second kerf 87, which corresponds to the groove of the present invention, on the surface of the calibration work CW.

[0064] This completes the second chop cut, and two kerfs 86, 87 with different cutting depths are formed on the surface of the calibration workpiece CW.

[0065] <Calf Photography> Fig. 7 is an explanatory diagram for explaining the photographing of the kerf 86 (as well as the kerf 87) by the microscope 23. As shown in Fig. 7 and the already described Fig. 4, the microscope 23, the movement control unit 72, the photographing control unit 74, and the image acquiring unit 76 constitute the photographed image acquiring unit of the present invention, and control the photographing of the kerfs 86, 87 in a planar view by the microscope 23 and the acquisition of photographed image data 88. Note that Fig. 7 will be explained by taking as an example a case where the entire kerfs 86, 87 do not fall within the photographing range of the microscope 23.

[0066] First, the movement control unit 72 drives the X drive unit 35 and the Y drive unit 46 to align the microscope 23 with one end of the kerf 86 in the X-axis direction and the Y-axis direction. Specifically, the relative positions of the blade 21 and the calibration workpiece CW in the X-axis direction and the Y-axis direction during chop cutting are known. In addition, since both the blade 21 (spindle 22) and the microscope 23 are fixed to the Z carriage 44, the relative position of the microscope 23 with respect to the blade 21 is also known. Furthermore, the length of the kerf 86 in the X-axis direction can also be estimated by experiment or simulation. Therefore, based on these alignment information, the movement control unit 72 can align the microscope 23 with one end of the kerf 86.

[0067] Next, the imaging control unit 74 controls the microscope 23 to image one end of the kerf 86 in a planar view using the microscope 23 while illuminating the kerf 86 with ring illumination or coaxial illumination using the microscope 23. As a result, photographed image data 88 of one end of the kerf 86 is input from the microscope 23 to the image acquisition unit 76.

[0068] Then, the movement control unit 72 drives the X drive unit 35 based on each of the above-mentioned alignment information to align the microscope 23 with the other end of the kerf 86 in the X-axis direction and the Y-axis direction. Furthermore, the imaging control unit 74 controls the microscope 23 to capture an image of the other end of the kerf 86 in a planar view using the microscope 23 while illuminating the kerf 86 with a ring illumination or a coaxial illumination. As a result, captured image data 88 of the other end of the kerf 86 is input from the microscope 23 to the image acquisition unit 76.

[0069] Similarly, under the control of the movement control unit 72 and the photography control unit 74, the microscope 23 photographs both ends of the kerf 87, and photographed image data 88 of both ends of the kerf 87 is input to the image acquisition unit 76.

[0070] In addition, when the entire kerfs 86, 87 fall within the photographing range of the microscope 23, the microscope 23 is aligned with the center of the kerfs 86, 87 in both the X-axis direction and the Y-axis direction for each kerf 86, 87, and photographs of the kerfs 86, 87 are taken by the microscope 23.

[0071] <Kerf dimension measurement> 8 is an explanatory diagram for explaining the measurement of the dimensions of the kerfs 86, 87 by the dimension measuring unit 78. To avoid complicating the explanation, the explanation will be given on the assumption that the entire kerfs 86, 87 are within the photographing range of the microscope 23, that is, the photographed image data 88 of the kerf 86 includes images of both ends of the kerf 86, and the photographed image data 88 of the kerf 87 includes images of both ends of the kerf 87.

[0072] 8 is the width direction (substantially the same direction as the Y axis direction) of the kerfs 86, 87, which corresponds to the width direction of the blade 21. The widthwise center, which is the center of the width direction (T axis direction) of the kerfs 86, 87, is defined as Tc (T = 0), and the lengthwise center, which is the center of the length direction (X axis direction) of the kerfs 86, 87 perpendicular to the width direction of the kerfs 86, 87, is defined as Xc (X = 0). The widthwise center and lengthwise center of the kerfs 86, 87 can be determined based on the relative positional relationship between the blade 21 and the calibration workpiece CW during the first and second chop cuts, and the relative positional relationship between the blade 21 and the microscope 23.

[0073] As shown in FIG. 8 and the above-described FIG. 4, the dimension measuring unit 78 measures the dimensions of both ends of each of the kerfs 86, 87 based on the known imaging magnification of the microscope 23 and the captured image data 88 of both ends of each of the kerfs 86, 87 acquired by the image acquisition unit 76.

[0074] Specifically, the dimension measuring unit 78 measures the distance X from the center (Xc) of the length of the kerf 86 to one end of the kerf 86 at each position in the width direction (T-axis direction) of the kerf 86. 1 (T) and the distance X from the longitudinal center (Xc) to the other end of the kerf 86 1 (T) and are measured by known techniques.

[0075] Similarly, the dimension measuring unit 78 measures the distance X from the center (Xc) of the length of the kerf 87 to one end of the kerf 87 at each position in the width direction (T-axis direction) of the kerf 87. 2 (T) and the distance X from the longitudinal center (Xc) to the other end of the kerf 87 2 (T) and are measured by known techniques.

[0076] <Calculation of radius, cutting depth, and tip shape of blade 21 by calculation unit> FIG. 9 shows the radius R of the blade 21 and the first cutting depth C in9 is an explanatory diagram for explaining the calculation of the above. In addition, the reference numeral 9A in the drawing indicates the first chop cut, and the reference numeral 9B in the drawing indicates the second chop cut. Also, in FIG. 9, the distance X 1 (T) is "Distance X 1 " and the distance X at any position in the width direction (T-axis direction) of the kerf 87 2 (T) is "Distance X 2 " is abbreviated.

[0077] As shown in FIG. 9 and the above-mentioned FIG. 4, the calculation unit 80 first calculates the dimension measurement results [distance X 1 and distance X 2 ] and the difference "dc" between the cutting depth of the blade 21 in the first and second chop cuts, the calculation unit 80 calculates the radius R at each position in the width direction (T-axis direction) of the blade 21. In addition, the calculation unit 80 calculates the first cutting depth C of the blade 21 at each position based on the calculation result of the radius R at each position in the width direction of the blade 21. in Hereinafter, the radius R and the cutting depth C at any position in the width direction of the blade 21 are calculated. in The calculation of is explained below.

[0078] The radius R at any position in the width direction of the blade 21 is calculated by the dimensional measurement results (distance X 1 and distance X 2 ) and the cutting depth for the first and second chop cuts, "C in ", "C in +dc" is expressed by the following formula [1]. Also, the first cutting depth C in is expressed by the following equation 2 based on the angle θ between a line segment (with radius R) connecting one end (the other end) of the kerf 86 and the center of the blade 21 as shown by reference symbol 9A in FIG. 9 and a line segment (shown by a dashed line in the figure) connecting the center of the kerf 86 and the center of the blade 21.

[0079]

number

[0080]

number

[0081] Based on the above [Formula 1] and [Formula 2], the radius R at any position in the width direction of the blade 21 is expressed by the following [Formula 3], and the first cut depth C (any cut of the present invention) is expressed by the following [Formula 3]. in is expressed by the following formula [4]. The diameter of the blade 21 can be calculated based on the radius R of the blade 21, and the first cutting depth C of the blade 21 can be calculated based on the radius R of the blade 21. in Based on the second cutting depth of blade 21, "C in +dc" can also be calculated. 1 " to "X 2 " Using the formula replaced by ", the second cutting depth "C in +dc" may be calculated directly.

[0082]

number

[0083]

number

[0084] FIG. 10 shows the relationship between the radius R and the cutting depth C at each position in the width direction of the blade 21 calculated by the calculation unit 80. in 11 is an explanatory diagram for explaining the calculation of the actual tip shape of the blade 21 by the calculation unit 80.

[0085] As shown in FIG. 10, the calculation unit 80 calculates the distance X 1 (T) measurement result and distance X at each position in the width direction of kerf 87 2Based on the measurement result of (T) and the difference dc, the calculations of the above [Formula 3] and [Formula 4] are repeatedly performed for each position in the width direction of the kerfs 86 and 87. As a result, the radius R and the cutting depth C at each position in the width direction of the blade 21 are calculated. in and are calculated.

[0086] As shown in FIG. 11, the shape of the kerfs 86, 87 formed on the surface of the calibration workpiece CW by the blade 21 is determined by the cutting depth C of the blade 21. in In accordance with the above, the shape of the tip of the blade 21 is elongated in the X-axis direction with respect to the actual shape of the tip of the blade 21. For this reason, the calculation unit 80 calculates the radius R and the cutting depth C at each position in the width direction of the blade 21. in The tip shape of the blade 21 obtained based on the above is converted into the actual tip shape of the blade 21. Note that since the specific conversion method is a known technique, a detailed description thereof will be omitted here.

[0087] Returning to Fig. 4, diagnosis unit 82 diagnoses the presence or absence of an abnormality in blade 21 using a known method based on the tip shape of blade 21 calculated by calculation unit 80. For example, when the design value of the radius of blade 21 is R0 and the radius at each position in the width direction of blade 21 is R(T), diagnosis unit 82 calculates the amount of wear of blade 21 [R0-R(T)] for each position in the width direction of blade 21, and diagnoses the presence or absence of an abnormality in blade 21 based on the calculation result of the amount of wear at each position. Then, diagnosis unit 82 outputs the diagnosis result of blade 21 to display unit 66.

[0088] [Dicing equipment operation] 12 corresponds to the blade diagnosis method of the present invention, and is a flowchart showing the flow of diagnosis processing of the blade 21 by the dicing apparatus 10 having the above-mentioned configuration. As shown in Fig. 12, the operator sucks and holds the calibration workpiece CW on the sub-table 38, and then inputs an operation to start diagnosis of the blade 21 to the operation unit 62.

[0089] In response to this diagnosis start operation, the movement control unit 72 drives the X drive unit 35 and the Y drive unit 46 to align the blade 21 with the calibration workpiece CW on the sub-table 38 in the X-axis and Y-axis directions. Next, the blade rotation control unit 70 drives the spindle 22 to rotate the blade 21. The movement control unit 72 also drives the Z drive unit 48 to lower the blade 21 to a predetermined lowered position, and then raises the blade 21. As a result, as shown in FIG. 5, the blade 21 cuts into the surface of the calibration workpiece CW at a cutting depth C. in Then, the calibration workpiece CW is chopped at 300° C., and a first kerf 86 is formed on the surface of the calibration workpiece CW (step S1, which corresponds to the groove forming step of the present invention).

[0090] After the kerf 86 is formed, as shown in Fig. 7, the movement control unit 72 drives the X drive unit 35 and the Y drive unit 46 based on the above-mentioned alignment information to align the microscope 23 with one end of the kerf 86 in the X-axis direction and the Y-axis direction. Next, the photography control unit 74 controls the microscope 23 to capture an image of one end of the kerf 86 in a planar view using the microscope 23. As a result, photographed image data 88 of the one end of the kerf 86 is input from the microscope 23 to the image acquisition unit 76 (step S2, which corresponds to the photographed image acquisition step of the present invention).

[0091] Then, the movement control unit 72 drives the X drive unit 35 based on each of the alignment information described above to align the microscope 23 with the other end of the kerf 86 in the X-axis direction and the Y-axis direction. Furthermore, the imaging control unit 74 controls the microscope 23 to capture an image of the other end of the kerf 86 in a planar view using the microscope 23. As a result, captured image data 88 of the other end of the kerf 86 is input from the microscope 23 to the image acquisition unit 76 (step S2, which corresponds to the captured image acquisition step of the present invention).

[0092] When the image acquisition unit 76 acquires the photographed image data 88 of both ends of the kerf 86, the dimension measurement unit 78 calculates the distance X at each position in the width direction of the kerf 86 as shown in FIG. 8 based on the known photographing magnification of the microscope 23 and the photographed image data 88 of both ends of the kerf 86. 1 (T) is measured (step S3, which corresponds to the dimension measuring step of the present invention).

[0093] After completing the measurement of the dimensions of the kerf 86, the movement control unit 72 drives at least one of the X drive unit 35 and the Y drive unit 46 to align the blade 21 in the X-axis direction and the Y-axis direction with the non-cutting area on the surface of the calibration workpiece CW. Next, the blade rotation control unit 70 drives the spindle 22 to rotate the blade 21. The movement control unit 72 also drives the Z drive unit 48 to lower the blade 21 to a lowered position that is further lower than the first lowered position by the difference dc, and then raises the blade 21. As a result, as shown in FIG. 6, the blade 21 cuts into the surface of the calibration workpiece CW by a cutting depth C. in The calibration workpiece CW is chopped at +dc to form a second kerf 87 on the surface thereof (step S4, which corresponds to the groove forming step of the present invention).

[0094] 7, after the formation of the kerf 87, the movement control unit 72 drives the X drive unit 35 and the Y drive unit 46, and the imaging control unit 74 controls the microscope 23 to capture images of both ends of the kerf 87 in a planar view by the microscope 23 (step S5, which corresponds to the captured image acquisition step of the present invention). Captured image data 88 of both ends of the kerf 87 are output from the microscope 23 to the image acquisition unit 76.

[0095] When the image acquisition unit 76 acquires the photographed image data 88 of both ends of the kerf 87, the dimension measurement unit 78 calculates the distance X at each position in the width direction of the kerf 87 as shown in FIG. 8 based on the known photographing magnification of the microscope 23 and the photographed image data 88 of both ends of the kerf 87. 2 (T) is measured (step S6, which corresponds to the dimension measuring step of the present invention).

[0096] After the measurement of the dimension of the kerf 87 is completed, the calculation unit 80 calculates the dimension measurement results [distance X 1 (T),X 2 Based on the difference "dc" in the cutting depth, the radius R at each position in the width direction of the blade 21 is calculated using the above formula [3] (step S7). in Even if the radius R of the blade 21 at each position in the width direction is unknown, it is possible to calculate the radius R of the blade 21 at each position in the width direction.

[0097] Next, the calculation unit 80 calculates the radius R of the blade 21 at each position in the width direction and measures the dimension of the kerf 86 at each position in the width direction [distance X 1 (T)] and the cutting depth C at each position in the width direction of the blade 21 is calculated using the above formula [4]. in is calculated (step S8).

[0098] Then, as shown in FIG. 11, the calculation unit 80 calculates the radius R and the cutting depth C at each position in the width direction of the blade 21. in The tip shape of the blade 21 obtained based on the above is converted into the actual tip shape of the blade 21 (step S9). Note that steps S7 to S9 correspond to the calculation step of the present invention.

[0099] When the tip shape of the blade 21 is calculated by the calculation unit 80, the diagnosis unit 82 diagnoses the presence or absence of an abnormality in the blade 21 based on the tip shape of the blade 21 using a known method, and outputs the diagnosis result to the display unit 66 (step S10).

[0100] The order of each step may be changed as appropriate. For example, chopping (steps S1 and S4) may be performed first, followed by photography (steps S2 and S5), then dimensional measurement (steps S3 and S6), and then steps from step S7 onwards may be performed.

[0101] [Effects of this embodiment] As described above, in the dicing device 10 of this embodiment, the blade 21 chops the calibration workpiece CW twice with different cutting depths, and the microscope 23 photographs each of the kerfs 86, 87. Based on the photographed image data 88 of each of the kerfs 86, 87, the dimensions of each of the kerfs 86, 87 are measured, thereby obtaining the surface height and cutting depth C of the calibration workpiece CW. in Even if the radius R and the cutting depth C at each position in the width direction of the blade 21 are unknown, in As a result, even in a device that does not have a mechanism (such as an air micrometer) for measuring the surface height (cut depth) of the calibration workpiece CW, the radius R and the tip shape of the blade 21 can be obtained based on the shapes of the kerfs 86, 87. This allows accurate diagnosis of the blade 21.

[0102] Also, as shown in Table 1 below, for example, the radius R and the cutting depth C of the blade 21 can be calculated by the conventional method based only on the photographed image data 88 of the kerf 86 formed in the first chop cut. in The first calculation result (R=55.50mm, C in =0.500mm) and the second calculation result (R=54.96mm, C in In this case, the radius R of the blade 21 and the cutting depth C in is not determined to be one, and it is not possible to determine whether the first calculation result or the second calculation result is correct.

[0103] [Table 1]

[0104] In contrast, as shown in Table 2 below, the radius R and the cutting depth C of the blade 21 are calculated based on the photographed image data 88 of the kerfs 86 and 87 formed in the first and second chop cuts. in By calculating the radius R and cutting depth C of the blade 21,in is determined to be either the first calculation result or the second calculation result. in Since the above can be calculated accurately, the diagnosis of the blade 21 can be performed accurately.

[0105] [Table 2]

[0106] In addition, even if the thickness (surface height) of the calibration workpiece CW changes due to the temperature characteristics of the calibration workpiece CW, the radius R and tip shape of the blade 21 can be accurately obtained. Furthermore, even if the radius R of the blade 21 is unknown, such as when the blade 21 is rapidly worn and the radius R of the blade 21 changes significantly, or when a used blade 21 is used, the radius R of the blade 21 can be accurately calculated in this embodiment, and the cutting depth C can be accurately calculated. in As a result, the blade 21 can be diagnosed accurately.

[0107] Furthermore, by observing the kerfs 86, 87 on the calibration workpiece CW on the sub-table 38, the kerfs 86, 87 can be measured in a stable environment, regardless of the visibility of the workpiece W (product workpiece), and the influence of the cutting characteristics of the workpiece W, such as chipping, can be eliminated. This allows the tip shape of the blade 21 to be accurately calculated. As a result, the blade 21 can be accurately diagnosed.

[0108] [others] In the above embodiment, the alignment between the blade 21 and the calibration workpiece CW, and the alignment between the microscope 23 and the kerfs 86, 87 are performed automatically, but these alignments may also be performed manually by the operator using the operation unit 62.

[0109] In the above embodiment, both ends of the kerfs 86, 87 are photographed by the microscope 23 (see FIG. 7), but only one end (the other end) of each may be photographed. That is, at least one of both ends of each of the kerfs 86, 87 is photographed by the microscope 23.

[0110] In the above embodiment, the calibration workpiece CW on the sub-table 38 is used as an example of the workpiece to be cut in the present invention. However, although the measurement accuracy is inferior to that of the above embodiment, the workpiece W (product workpiece) on the cutting table 31 may also be used as the workpiece to be cut in the present invention.

[0111] In the above embodiment, the first chop cut and the second chop cut on the surface of the calibration workpiece CW are performed at different positions on the surface of the calibration workpiece CW, but both chop cuts may be performed at the same position on the surface of the calibration workpiece CW. In this case, after the kerf 86 formed in the first chop cut is photographed with the microscope 23, the second chop cut is performed with a deeper cutting depth than the first chop cut. This makes it possible to reduce the amount of calibration workpiece CW used. Note that when chop cuts are performed three or more times, the cutting depth is similarly increased each time a chop cut is performed.

[0112] In the above embodiment, the chop cut is performed twice on the calibration workpiece CW with different cutting depths, but the chop cut may be performed three or more times on the calibration workpiece CW. In this case, the dimensions of each kerf are measured based on the photographed image data 88 of three or more types of kerfs, and the radius R and the cutting depth C at each position in the width direction of the blade 21 are calculated based on the measurement results of the dimensions of each kerf. in Calculate the following. [Explanation of symbols]

[0113] 10...Dicing equipment 21…Blade 22…Spindle 23...Microscope 31…Cutting table 35…X drive section 38…Subtable 46…Y drive section 48…Z drive section 60...General control unit 70...Blade rotation control section 72...Movement control unit 74...imaging control unit 76…Image acquisition section 78…Dimensional measurement section 80...Arithmetic section 86,87…Calf 88...Captured image data

Claims

1. a groove forming step in which a groove is formed on the surface of the workpiece by a disk-shaped blade, the groove processing being performed multiple times with different cutting depths of the blade; an image acquisition step of acquiring an image of the groove in a plan view for each of the grooves formed by the multiple groove processing steps; a dimension measuring step of measuring dimensions of each of the grooves based on the photographed images of each of the grooves acquired in the photographed image acquiring step; and a calculation step of calculating a radius of the blade based on the results of forming the plurality of grooves having different cutting depths of the blade in the groove forming step, the measurement results of the dimensions of the plurality of grooves having different depths in the dimension measurement step, and the difference in cutting depth of the blade when the groove processing is performed a plurality of times in the groove forming step.

2. 2. The blade diagnosis method according to claim 1, wherein in the calculation step, a cutting depth of the blade in any one of the multiple groove machining operations is calculated based on a measurement result of the dimension of the groove formed in any one of the multiple groove machining operations and a calculation result of a radius of the blade.

3. The blade diagnosis method according to claim 1 , wherein in the photographed image acquisition step, the photographed image that includes at least one of both ends of the groove is acquired for each of the grooves.

4. A groove forming control unit that performs groove processing to form a groove on a surface of a workpiece by a disk-shaped blade multiple times with different cutting depths of the blade; an image acquisition unit that acquires an image of the groove in a plan view for each of the grooves formed by the multiple groove processing operations; a dimension measuring unit that measures dimensions of the groove for each of the grooves based on the photographed images of the grooves acquired by the photographed image acquisition unit; a calculation unit that calculates a radius of the blade based on the formation results of the multiple grooves having different cutting depths of the blade by the groove formation control unit, the measurement results of the dimensions of the multiple grooves having different depths by the dimension measurement unit, and the difference in cutting depth of the blade when the groove processing is performed multiple times by the groove formation control unit.

5. 5. The blade diagnostic device according to claim 4, wherein the calculation unit calculates a cutting depth in an arbitrary one of the multiple groove machining operations based on a measurement result of the dimension of the groove formed in the arbitrary one of the multiple groove machining operations and a calculation result of the radius of the blade.

6. 6. The blade diagnosis device according to claim 5, wherein the blade tip shape acquired by the photographed image acquisition unit is converted into an actual blade tip shape based on the calculation results of the cutting depth and the blade radius by the calculation unit.

Images