JP7818754B2 - Blade breakage detection device - Google Patents

Description

The present invention relates to a blade breakage detection device that detects blade breakage by irradiating light onto the blade.

Dicing machines, which divide wafers with multiple devices formed on their surface into individual chips, are equipped with a blade that is rotated at high speed by a spindle and a table that holds the wafer by suction. During the dicing process in semiconductor manufacturing, the blade of the dicing machine rotates at high speed to groove or cut the wafer held by suction on the table.

Furthermore, the dicing process may include a grinding process in which the wafer is ground thinly. Grinding the wafer thinly in the grinding process can create knife edges on the wafer's periphery, which can lead to processing defects. Therefore, to prevent knife edges from forming, a process called edge trimming is sometimes implemented, in which a blade is used to create a stepped edge on the wafer's periphery.

When performing edge trimming, a thicker blade than usual may be used depending on the amount of edge removal. Even when processing the wafer surface with a rotating blade, as is commonly done in dicing processes, a thick blade may be used not for the purpose of dividing the wafer into chips, but for the purpose of forming the shape of the groove itself. While the thickness of a blade normally used is several microns, the thickness of the thick blade mentioned above is between 1 mm and 5 mm.

A variety of technologies have been proposed for detecting blade damage in dicing machines. For example, Patent Document 1 describes a blade damage detection device that receives light emitted from a light-emitting element with a light-receiving element and detects blade damage based on the amount of light received.

JP 2009-83077 A

The blade breakage detection device described in Patent Document 1 employs a configuration in which light is emitted from a light-emitting element parallel to the blade's rotation axis and received by a light-receiving element. However, with this configuration, for example, if a chip occurs on only one side of the outer periphery of a thick blade, the chip may not be detected.

In addition, in the past, thick blades were inspected for chips only on the outer periphery of the front or back surface only after an abnormality occurred in a product that had undergone dicing processing. In this inspection, workers visually check the condition of the blade using a microscope or other device to detect chips. In this way, when a worker visually detects blade damage, the blade must be temporarily removed from the dicing device, during which time the dicing device cannot be operated, reducing productivity. Furthermore, because workers only check the blade once an abnormality occurs in a product that has undergone dicing processing, there is a risk of producing a large number of defective products.

The present invention was made in light of these circumstances, and its purpose is to provide a damage detection device that can detect chips that occur on only one side of the outer periphery of a blade.

To achieve the above objective, one aspect of the present invention is a blade breakage detection device for detecting breakage in a rotatable blade, and includes a light irradiation means that irradiates light obliquely with respect to the rotation axis of the blade toward the outer periphery of the blade, a light receiving means that receives light irradiated from the light irradiation means that passes through the outer periphery of the blade, and a detection means that detects blade breakage based on the light reception results of the light receiving means.

In this embodiment, light is irradiated toward the outer periphery of the blade at an angle to the blade's rotation axis. This makes it possible to detect chips that occur on only one side of the outer periphery of the blade.

Preferably, the light irradiating means has a light emitting element that emits light having an optical axis extending from one end to the other end of the outer periphery of the blade.

Preferably, the angle of inclination of the optical axis relative to the blade rotation axis is within the range of 30 to 60 degrees.

Another aspect of the present invention is a blade breakage detection device for detecting breakage in a rotatable blade, and includes a light irradiation means that irradiates light that has passed through a first lens having an optical axis parallel to the rotation axis of the blade toward the outer periphery of the blade, a light receiving means that faces the first lens across the outer periphery of the blade and receives light that has passed through a second lens having the same optical axis as the first lens, and a detection means that detects breakage of the blade based on the light reception results of the light receiving means.

In this embodiment, light that passes through the first lens is directed toward the outer periphery of the blade, and light that passes through the second lens is received. This makes it possible to detect chips that occur on only one side of the outer periphery of the blade.

Preferably, the numerical aperture NA of the first lens and the second lens is 0.4 or greater.

Preferably, the focal positions of the first and second lenses are located at the center of the blade's width.

This invention makes it possible to detect chips that occur on only one side of the blade's outer periphery.

FIG. 1 is a perspective view showing the appearance of a dicing machine equipped with a blade breakage detection device. FIG. 2 is a perspective view showing the configuration of the processing unit. FIG. 3 is a perspective view showing the structure of the tip of the spindle. FIG. 4 is a schematic structural diagram showing the structure of a detection unit according to an embodiment of the present invention. FIG. 5 is a diagram illustrating the chipping patterns of a thin blade and a thick blade. FIG. 6 is a diagram illustrating the detection unit of the blade breakage detection device. FIG. 7 is a functional block diagram of a control unit that controls the operation of the blade breakage detection device. FIG. 8 is a diagram showing a light receiving voltage detected by the light receiving amount detection unit. FIG. 9 is a diagram illustrating another example of the detection unit of the blade breakage detection device. FIG. 10 is a diagram illustrating the detection unit of the blade breakage detection device. FIG. 11 is a diagram illustrating the detection unit of the blade breakage detection device.

A preferred embodiment of the blade breakage detection device according to the present invention will now be described with reference to the accompanying drawings.

Figure 1 is a perspective view showing the exterior of a dicing machine equipped with the blade breakage detection device 10 of the present invention.

The dicing device 100 includes a processing unit 110 having a pair of spindles 106, 106 arranged opposite each other and a work table 108 that holds the workpiece W by suction. The dicing device 100 also includes a cleaning unit 112 that spin-cleans the processed workpiece W, a load port 114 on which a cassette containing multiple workpieces W is placed, a transport device 116 that transports the workpieces W, and a control unit 118 that controls the overall operation of each unit.

The spindle 106 is, for example, a spindle with a built-in high-frequency motor, and a blade 102 that performs cutting on the workpiece W is attached to the tip of the spindle 106. The blade 102 is rotated by the spindle 106 at high speeds of, for example, 8,000 rpm to 60,000 rpm.

Blade 102 is a cutting blade configured in a disk shape. Blade 102 can be an electroplated blade in which diamond abrasive grains or CBN (Cubic Boron Nitride) abrasive grains are electroplated with nickel, or a resin blade in which the grains are bonded with resin. Furthermore, blade 102 is typically a thick blade with a thickness of 1 mm to 5 mm. The diameter of blade 102 is, for example, 50 mm.

Figure 2 is a perspective view showing the configuration of the processing unit 110.

The processing unit 110 shown in Figure 2 has an X table 126. This X table 126 is guided by an X guide 122 provided on an X base 120, and is driven by a linear motor 124 in the X-axis direction indicated by X-X in Figure 2. This X table 126 is equipped with a rotary table 128 that rotates around the Z axis, and the work table 108 is provided on this rotary table 128.

The processing unit 110 also has a Y base 130. This Y base 130 is installed so as to straddle the linear motor 124. A Y table 134 is installed on the side of this Y base 130, guided by a Y guide 132 and driven in the Y-axis direction indicated by Y-Y in FIG. 2 by a drive unit (not shown). Each Y table 134 is equipped with a Z table 136 that is driven in the Z-axis direction by a drive unit (not shown). The spindle 106, with the blade 102 attached to its tip, is also fixed to the Z table 136. With this structure of the processing unit 110, the blade 102 is indexed in the Y-axis direction and cut in the Z-axis direction, while the work table 108 is cut in the X-axis direction. The X, Y, and Z axes are mutually perpendicular, with the X and Y axes oriented horizontally and the Z axis oriented vertically (up and down).

Figure 3 is an oblique view showing the tip structure of the spindle 106.

As shown in Figure 3, a wheel cover 15 that covers the top of the blade 102 is attached to the tip of the spindle 106. This wheel cover 15 is constructed by assembling components such as a front cover 16, a rear cover 18, and a nozzle block 20, and has the function of suppressing the scattering of cutting powder, cutting water, and cooling water that are generated when machining the workpiece W.

The end of a hose 21 is connected to the upper surface of the rear cover 18, and cutting water is supplied from the hose 21. The supplied cutting water is sprayed toward the rotating blade 102 from a nozzle 23 provided on the wheel cover 15. In addition, the end of a hose 22 is connected to the upper surface of the nozzle block 20, and cooling water is supplied from the hose 22. The supplied cooling water is sprayed toward the rotating blade 102 and workpiece W from a pair of L-shaped nozzles 24, 24 arranged opposite each other with the blade 102 in between.

The wheel cover 15 configured as described above is provided with the detection unit 12 that constitutes the blade breakage detection device 10, and a feed mechanism 14 that moves the detection unit 12 in the Z-axis direction. The blade breakage detection device 10 is composed of the detection unit 12 and a control unit 118 (see Figures 1 and 7).

Next, the structure of the detection unit 12 will be described in detail. In the following explanation, we will first explain the embodiment that serves as the basis for explaining the present invention using Figure 4, and then explain the present invention.

Figure 4 is a diagram showing an example of a detection unit 12 according to an embodiment of the present invention, and is a schematic structural diagram showing the structure of the detection unit 12. Figure 4 shows a schematic structural diagram of the detection unit 12 as viewed from the X-axis direction in Figure 3.

As shown in Figure 4, the detection unit 12 is composed of a light-emitting unit 26 and a light-receiving unit 28. In the example shown in Figure 4, the light-emitting unit 26 and the light-receiving unit 28 are integrally formed by the detection unit main body 12A above the Z axis of the blade 102, and the light-emitting surface 36 and the light-receiving surface 44 are arranged opposite each other with the blade 102 sandwiched between them.

The light-emitting unit 26 has a light-emitting element 30, such as a light-emitting diode or laser diode; an optical cable 32 that transmits light from the light-emitting element 30; a light-emitting optical path 26A through which the light emitted from the optical cable 32 passes; and a right-angle prism 34 attached to the bottom of the light-emitting optical path 26A that reflects and emits the light transmitted by the light-emitting optical path 26A. The light-emitting end face of the right-angle prism 34 forms the light-emitting surface 36 of the light-emitting unit 26. This light-emitting surface 36 is positioned away from the side of the blade 102.

The light receiving unit 28 has a light receiving element 38 such as a photodiode, an optical cable 40 connected to the light receiving element 38, a light receiving optical path section 28A through which light incident from the right-angle prism 42 passes, and a right-angle prism 42 attached to the bottom of the light receiving optical path section 28A and connected to the optical cable 40. The light incident end face of the right-angle prism 42 forms the light receiving surface 44 of the light receiving unit 28. This light receiving surface 44 is positioned away from the side surface of the blade 102.

The light-emitting surface 36 and the light-receiving surface 44 are arranged opposite each other, sandwiching the outer periphery 102R, which is the cutting edge of the blade 102. Of the light emitted from the light-emitting surface 36 toward the light-receiving surface 44, the light that is not blocked by the outer periphery 102R is incident on the light-receiving surface 44. The light incident on the light-receiving surface 44 is received by the light-receiving element 38. The control unit 118 (see Figure 1), which will be described later, detects damage to the blade 102 based on the amount of light received by the light-receiving element 38.

As shown in Figure 4, in the embodiment underlying the present invention, the optical axis portion La between the light-emitting surface 36 and the light-receiving surface 44 of the optical axis L of the detection unit 12 is installed so as to be parallel to the rotation axis C of the blade 102. In other words, the optical axis L of the light irradiated onto the outer periphery 102R of the blade 102 is parallel to the rotation axis C of the blade 102, and the light emitted from the light-emitting surface 36 is irradiated towards the outer periphery 102R of the blade 102 in a direction parallel to the rotation axis C of the blade 102.

Here, we will explain the issues surrounding the underlying embodiment of the present invention.

Figure 5 is a diagram explaining the chipping patterns of thin and thick blades. Note that Figure 5 shows a simplified illustration of the light-emitting unit 26 and light-receiving unit 28 that make up the detection unit 12. Also, to make the invention easier to understand, the thickness of each blade is exaggerated.

In Figure 5, reference numeral 202 shows a schematic diagram illustrating a chip in the thin blade 210, and reference numeral 204 shows a schematic diagram illustrating a chip in the thick blade 102. In both reference numerals 202 and 204, the optical axis L of the detection unit 12 (corresponding to the optical axis portion La between the light-emitting surface 36 and the light-receiving surface 44 in Figure 4) is parallel to the rotation axis C of the blade 210. Furthermore, the light R emitted from the light-emitting unit 26 is a beam of light with a diameter of 1 mm to 2 mm.

As shown by the reference numeral 202, when a chip Q1 occurs in the thin blade 210, the light R emitted from the light-emitting unit 26 passes through the chip Q1 of the blade 210 without being blocked by the blade 210 during one rotation of the blade 210, and is received by the light-receiving unit 28. Therefore, when a chip Q1 exists in the blade 210, a peak M (see Figure 7) is detected in the amount of light received by the light-receiving unit 28 by rotating the blade 210. This allows the blade breakage detection device 10 to detect the chip Q1.

On the other hand, reference numeral 204 shows a case where a chip Q2 has occurred on the outer periphery 102R of a thick blade 102. The chip Q2 has occurred only on the first surface 102a side of the outer periphery 102R of the blade 102. In such a case, even if light R emitted from the light-emitting unit 26 is directed at the location where the chip Q2 has occurred, it is blocked by the second surface 102b (the back surface of the first surface) of the blade 102 and is not received by the light-receiving unit 28. Therefore, even if a chip Q2 exists on the blade 102, the light-receiving unit 28 cannot receive the light R emitted from the light-emitting unit 26, even at the position where the chip Q2 exists, and the peak M cannot be detected in the amount of light received by the light-receiving unit 28.

In a thick blade 102, a chip Q2 may occur only on the first surface 102a or the second surface 102b. However, as shown in Figure 5, chip Q2 cannot be detected even if light parallel to the rotation axis C of the blade 102 is irradiated onto the outer periphery 102R of the blade 102. Therefore, the embodiments of the present invention (first and second embodiments) described below make it possible to detect chip Q2 that occurs on only one surface (first surface 102a or second surface 102b) of the outer periphery 102R of a thick blade 102.

First Embodiment
A first embodiment of the blade breakage detection device 10 of the present invention will be described. The following description will focus on differences from the embodiment on which the present invention is based (particularly the detection unit 12 described in FIG. 4).

Figure 6 is a diagram illustrating the detection unit 12 of the blade breakage detection device 10. Similar to Figure 5, Figure 6 shows a simplified illustration of the light-emitting unit 26 and light-receiving unit 28, and the light R emitted from the light-emitting unit 26 is a beam of light with a diameter φ of 1 to 2 mm. The light-emitting unit 26 described below is the light-irradiating means of the present invention, and the light-receiving unit 28 is the light-receiving means of the present invention.

As shown in FIG. 6 , in the detection unit 12 of the first embodiment, the optical axis L of the light R irradiated onto the outer periphery 102R of the blade 102 is inclined obliquely with respect to the rotation axis C of the blade 102. That is, the light R emitted from the light-emitting unit 26 is irradiated toward the outer periphery 102R of the blade 102 in a direction oblique to the rotation axis C of the blade 102. By irradiating the outer periphery 102R of the blade 102 with light R having an optical axis L inclined obliquely with respect to the rotation axis C of the blade 102 from the light-emitting unit 26 in this manner, the light is received by the light-receiving unit 28 at the location of the chip Q2 without being blocked by the blade 102. This allows the blade breakage detection device 10 to detect chip Q2 that has occurred on only one surface (first surface 102a) of the outer periphery 102R of the blade 102.

Here, the inclination angle α of the optical axis L with respect to the rotation axis C is preferably in the range of 30 to 60 degrees. The inclination angle α refers to the inclination angle of the optical axis L (corresponding to the optical axis portion La between the light-emitting surface 36 and the light-receiving surface 44 in FIG. 4) with respect to the rotation axis C when the blade 102 is viewed from the X-axis direction as shown in FIG. 4. By setting the inclination angle α within this range, the chip Q2 can be detected with high sensitivity without the light R being blocked by the blade 102. Furthermore, by setting the inclination angle α to approximately 45 degrees, the chip Q2 can be detected with even higher sensitivity. Here, the optical axis L refers to the optical axis that indicates the optical path of the light R from the light-emitting surface 36 of the light-emitting unit 26 (see FIG. 4) to its reception by the light-receiving surface 44 of the light-receiving unit 28 (see FIG. 4).

Figure 7 is a functional block diagram of the control unit 118, which controls the operation of the blade breakage detection device 10. Note that the control unit 118 controls the entire dicing device 100, but Figure 7 only shows the functional units that control the operation of the blade breakage detection device 10.

The control unit 118 includes a light-receiving amount detection unit 62 that detects the amount of light received by the light-receiving element 38 (see Figure 4) per unit time, and a damage detection unit 64 that detects damage to the blade 102 based on the detection results of the light-receiving amount detection unit 62. The control unit 118 is configured with one or more processors, including a CPU (Central Processing Unit) and FPGA (Field-Programmable Gate Array), and one or more memories. The control unit 118 corresponds to the detection means of the present invention.

Figure 8 shows the light receiving voltage detected by the light receiving amount detection unit 62.

Figure 8 shows the light-receiving voltage when light transmitted through the notch Q2 is received by the detection unit 12 shown in Figure 6.

When the blade 102 rotates at a predetermined cycle, peaks M of the light-receiving voltage caused by light passing through the chip Q2 and received by the light-receiving unit 28 can be periodically obtained. The light-receiving element 38 that constitutes the light-receiving unit 28 outputs a light-receiving voltage corresponding to the amount of light received. The breakage detection unit 64 then detects this periodically obtained peak M to detect breakage (chip Q2) in the blade 102. Therefore, the blade breakage detection device 10 can automatically detect chip Q2 in the blade 102 by having the light-receiving amount detection unit 62 output a light-receiving result, which is a light-receiving voltage corresponding to the amount of light received, and having the breakage detection unit 64 detect peaks M.

As explained above, in the detection unit 12 of the blade breakage detection device 10 of this embodiment, the optical axis L of the light R irradiated onto the outer periphery 102R of the blade 102 is configured to be inclined obliquely with respect to the rotation axis C of the blade 102, making it possible to detect chips that have occurred on only one side of the outer periphery 102R of the blade 102.

While the above description has been given as an example of detecting a chip Q2 occurring on the outer periphery 102R on the first surface 102a side of the blade 102, this embodiment is not limited to this. For example, as shown in FIG. 9, to detect a chip Q2 occurring on the outer periphery 102R on the second surface 102b side, the direction in which the optical axis L of the light R irradiated onto the outer periphery 102R of the blade 102 is inclined obliquely with respect to the rotation axis C of the blade 102 can be reversed from the configuration shown in FIG. 6. That is, the distance between the light-projecting unit 26 and the rotation axis C can be made shorter than the distance between the light-receiving unit 28 and the rotation axis C (in other words, the light-projecting unit 26 can be brought closer to the rotation axis C than the light-receiving unit 28), so that the light R irradiated from the light-projecting unit 26 toward the chip Q2 on the first surface 102a side of the blade 102 can be received by the light-receiving unit 28.

Furthermore, since there is a certain tendency for chipping Q2 to occur on the surface (first surface 102a or second surface 102b) of the outer periphery 102R of the blade 102 depending on the usage pattern of the blade 102, for example, two types of detection units (a detection unit corresponding to the configuration shown in Figure 6 and a detection unit corresponding to the configuration shown in Figure 9) in which the optical axis L of light R irradiated onto the outer periphery 102R of the blade 102 has different inclinations may be provided, or both functions may be realized by a single detection unit.

The embodiment is not particularly limited as long as it has the function of irradiating the outer periphery 102R of the blade 102 with light having an optical axis L inclined obliquely with respect to the rotation axis C of the blade 102. For example, the detection unit 12 may be realized by arranging the light-emitting element 30 and the light-receiving element 38 in any position and combining a reflective member such as a mirror or prism to guide light from the light-emitting element 30 to the light-receiving element 38. Furthermore, the detection unit 12 shown in Figure 4 may be realized by tilting it about the X-axis direction.

Furthermore, the blade breakage detection device 10 may be equipped with, for example, a tilt mechanism that can change the tilt angle of the detection unit 12, and when a user selects any of the three detection modes (1) normal mode (optical axis parallel to the blade rotation axis), (2) first surface chipping detection mode (corresponding to Figure 6), or (3) second surface chipping detection mode (corresponding to Figure 9) via the operation unit (not shown), the control unit 118 may change the tilt angle α of the detection unit 12 to an angle corresponding to the selected mode and perform damage detection.

Second Embodiment
Next, a second embodiment will be described. In the first embodiment described above, the optical axis L of the light R irradiated onto the outer periphery 102R of the blade 102 is inclined obliquely with respect to the rotation axis C of the blade 102. In contrast, in the second embodiment, a pair of lenses (a light-emitting unit-side lens 50 and a light-receiving unit-side lens 52 (see FIGS. 10 and 11 )) with a high numerical aperture (NA) are used to enable detection of chips occurring on only one surface of the outer periphery 102R of the blade 102.

Figures 10 and 11 are diagrams illustrating the detection unit 12 of the blade breakage detection device 10 of the second embodiment. Note that parts that were previously described in Figures 5 and 6 are given the same reference numerals and will not be described again.

10 and 11, the light-emitting unit 26 has a light-emitting unit-side lens 50, and the light-receiving unit 28 has a light-receiving unit-side lens 52. The light-emitting unit-side lens 50 corresponds to the first lens of the present invention, and the light-receiving unit-side lens 52 corresponds to the second lens of the present invention. The light-irradiating means of the present invention includes the light-emitting unit-side lens 50, and is configured to emit light from the light-emitting element 30 (see FIG. 4) through the light-emitting unit-side lens 50, optionally in combination with a reflective member such as a mirror or prism (not shown) or other optical members. The light-receiving means of the present invention includes the light-receiving unit-side lens 52, and is configured to receive light incident from the light-receiving unit-side lens 52 by the light-receiving element 38 (see FIG. 4), optionally in combination with a reflective member such as a mirror or prism (not shown) or other optical members. The light-emitter-side lens 50 and the light-receiving-side lens 52 have the same lens optical axis S (coincident with the optical axis L of the detection unit 12), and are arranged so that the lens optical axis S is parallel to the rotation axis C of the blade 102. The light-emitter-side lens 50 and the light-receiving-side lens 52 are composed of lenses with a high numerical aperture NA. The light-emitter-side lens 50 and the light-receiving-side lens 52 are arranged facing each other, sandwiching the outer periphery 102R of the blade 102. The focal positions of the light-emitter-side lens 50 and the light-receiving-side lens 52 are located at the center Ra of the blade 102 in the width direction.

As shown in Figure 10, when no chip Q2 occurs in the blade 102, of the light incident on the light-projecting unit side lens 50, light that passes through the outer periphery of the light-projecting unit side lens 50 (the upper and lower parts of the lens in Figure 10) is blocked by the first surface 102a and second surface 102b of the blade 102. On the other hand, light R that passes through the center of the light-projecting unit side lens 50 (indicated by the arrow in Figure 10) is incident on the light-receiving unit side lens 52 and is detected by the light-receiving unit 28.

In contrast, when there is a notch Q2 in the blade 102 as shown in Figure 11, of the light incident on the light-projecting unit side lens 50, light R that passes through a portion of the outer periphery of the light-projecting unit side lens 50 (the lower side of the lens in Figure 11) is blocked by the blade 102. On the other hand, light R that passes through a portion of the outer periphery of the light-projecting unit side lens 50 (the upper side of the lens in Figure 11) is not blocked by the notch Q2 in the blade 102, and is detected by the light-receiving unit 28 along with light that passes through the center of the blade 102.

As a result, the amount of light detected by the light receiving unit 28 changes depending on whether or not there is a chip Q2 in the blade 102, making it possible to detect chip Q2 (breakage) in the blade 102 from the detection results. Since the fact that chip Q2 is detected by changes in the amount of light detected by the light receiving unit 28 has already been explained using Figures 7 and 8, further explanation will be omitted here.

Furthermore, if chipping occurs on both sides of the blade 102 (first surface 102a and second surface 102b), light R that passes through part of the outer periphery of the light-emitter-side lens 50 (the upper and lower sides of the lens in Figure 11) is detected by the light-receiving unit 28 without being blocked by the blade 102. Therefore, in this case, the amount of light detected by the light-receiving unit 28 is the greatest, making it possible to detect chipping not only on one side of the blade 102 but on both sides.

It is preferable that the numerical aperture NA of the light-emitter-side lens 50 and the light-receiver-side lens 52 be, for example, 0.4 or greater. If the numerical aperture NA of the light-emitter-side lens 50 and the light-receiver-side lens 52 is 0.4 or greater, the amount of light detected by the light-receiving unit 28 changes depending on the occurrence of chipping Q2 in the outer periphery 102R of the blade 102, allowing chipping Q2 to be detected with high accuracy.

As an example, in Figure 11, if the thickness of the blade 102 is 3 mm, the distance between the blade 102 and the light-emitter side lens 50 and the light-receiving side lens 52 is 2.25 mm, the lens thickness of the light-emitter side lens 50 and the light-receiving side lens 52 is 2.5 mm, the focal length of the light-emitter side lens 50 and the light-receiving side lens 52 is 5 mm, the lens diameter of the light-emitter side lens 50 and the light-receiving side lens 52 is 5 mm, and the numerical aperture NA is 0.45, even a chip Q2 of 1 mm or less that occurs in the blade 102 can be detected.

As described above, in the detection unit 12 of the blade breakage detection device 10 of the second embodiment, a pair of light-emitter-side lenses 50 and light-receiver-side lenses 52 with a high numerical aperture NA are positioned opposite each other across the outer periphery 102R of the blade 102, and the lens optical axes S of the pair of light-emitter-side lenses 50 and light-receiver-side lenses 52 are positioned parallel to the rotation axis C of the blade 102. As a result, even if a chip Q2 occurs on only one surface (first surface 102a or second surface 102b) of the outer periphery 102R of the blade 102, the light R irradiated onto the outer periphery 102R of the blade 102 via the pair of light-emitter-side lenses 50 and light-receiver-side lenses 52 with a high numerical aperture NA is received by the light-receiving unit 28, and the amount of light detected by the light-receiving unit 28 changes depending on the occurrence of the chip Q2 on the outer periphery 102R of the blade 102. Therefore, according to the second embodiment, as with the first embodiment, it is possible to detect chips that have occurred on only one side of the outer periphery 102R of the blade 102. Furthermore, it is possible to detect not only chips that have occurred on only one side of the blade 102, but also chips that have occurred on both sides of the outer periphery 102R of the blade 102.

The above describes examples of the present invention, but it goes without saying that the present invention is not limited to the above-described embodiments, and various modifications are possible without departing from the spirit of the present invention.

10...Blade breakage detection device, 12...Detection unit, 14...Feed mechanism, 15...Wheel cover, 16...Front cover, 18...Rear cover, 20...Nozzle block, 21...Hose, 22...Hose, 23...Nozzle, 24...Nozzle, 26...Light-emitting section, 26A...Light-emitting optical path section, 28...Light-receiving section, 28A...Light-receiving optical path section, 30...Light-emitting element, 32...Optical cable, 34...Rectangular prism, 36...Light-emitting surface, 38...Light-receiving element, 40...Optical Cable, 42...Right-angle prism, 44...Light-receiving surface, 50...Light-emitting unit lens, 52...Light-receiving unit lens, 62...Light-receiving amount detection unit, 64...Breakage detection unit, 100...Dicing device, 102...Blade, 102R...Outer periphery, 102a...First surface, 102b...Second surface, 106...Spindle, 108...Work table, 110...Processing unit, 112...Cleaning unit, 114...Load port, 116...Transport device, 118...Control unit, C...Rotation axis, L...Optical axis

Claims (2)

1. A blade breakage detection device for detecting breakage of a rotatable blade, comprising:
a light irradiation means for irradiating light obliquely with respect to the rotation axis only toward a corner of the outer periphery of the blade formed by one of the side surfaces on both sides in the axial direction of the rotation axis of the blade and the outer periphery of the blade;
a light receiving means for receiving light emitted from the light emitting means and transmitted through the outer periphery of the blade;
a detection means for detecting damage to the corner of the blade based on the light reception result of the light receiving means;
Equipped with
the inclination angle of the optical axis of the light irradiation means with respect to the rotation axis of the blade is within a range of 30 degrees to 60 degrees ;
Blade breakage detection device. the light irradiating means has a light emitting element that emits light having the optical axis extending from one end to the other end across the outer periphery of the blade,
The blade breakage detection device according to claim 1 .