JP7370230B2 - Machining groove detection device and cutting device - Google Patents

Description

The present invention relates to a machined groove detection device and a cutting device.

2. Description of the Related Art In order to cut a workpiece, such as a semiconductor wafer, along streets to form chips, a cutting device (see, for example, Patent Document 1) that is equipped with a cutting blade that cuts the workpiece is used.

Japanese Patent Application Publication No. 6-112310

In the cutting apparatus shown in Patent Document 1 and the like, if the cutting blade becomes clogged or chipped, chips may also occur on both sides of the cutting groove, which is a machining groove formed in a workpiece. In particular, the cutting device shown in Patent Document 1 has a problem in that chips that occur on the back side of the workpiece are often larger than chips that occur on the front surface, which significantly deteriorates the quality of the device.

In order to confirm the chipping that occurs in the cut grooves on the back side of the workpiece as described above (hereinafter referred to as backside chipping), it is sufficient to image the cut grooves formed on the workpiece from the back side. A dicing tape is attached to the back side of the workpiece, and the dicing tape has minute irregularities to make it easier to remove from the chuck table. It is difficult to image the chip on the back side. Therefore, it was necessary to peel off the dicing tape and observe it, which was a time-consuming task.

The present invention has been made in view of the above facts, and an object of the present invention is to provide a machined groove detection device and a cutting device that can easily detect chips on the back side of a workpiece.

In order to solve the above-mentioned problems and achieve the purpose, a machined groove detection device of the present invention is a machined groove detection device that detects a machined groove formed in a workpiece to which a dicing tape is attached on the back side. a holding means for holding the workpiece, and an ultrasonic generation unit for transmitting ultrasonic waves to the workpiece from the surface side of the workpiece held by the holding means via the dicing tape. , and an ultrasonic unit including an ultrasonic receiving unit that receives ultrasonic waves (reflected waves) reflected from the workpiece, and the holding means and the ultrasonic unit are arranged parallel to the surface of the workpiece. a moving means for relatively moving in a direction; a water layer forming means for forming a water layer between the workpiece and the ultrasonic unit; an imaging unit that images the image as light and dark, and the moving means relatively moves the workpiece in which the processing groove is formed and the ultrasonic unit along the dividing line. The ultrasonic generation unit transmits ultrasonic waves so that the ultrasonic waves are converged on the back side of the processing groove formed in the workpiece, and based on the reflected wave intensity of the ultrasonic waves on the back side of the workpiece. The present invention is characterized in that an image including the machined groove on the back side of the workpiece is generated, and the state of both edges of the machined groove on the back side is detected.

The cutting device of the present invention includes a chuck table that holds a workpiece, a cutting means that includes a cutting blade that cuts the workpiece held on the chuck table, and detects a cutting groove formed by the cutting means. A cutting device comprising a detection means, wherein the detection means is the machined groove detection device.

In the cutting device, the chuck table may be the holding means.

The present invention has the effect that chips on the back side of a workpiece can be easily detected.

FIG. 1 is a perspective view showing a configuration example of a cutting device according to a first embodiment. FIG. 2 is a cross-sectional view showing a state in which the machined groove detection device of the cutting apparatus shown in FIG. 1 detects a machined groove. FIG. 3 is a diagram schematically showing the configuration of a main part of the machined groove detection device of the cutting device shown in FIG. 1. As shown in FIG. FIG. 4 is a diagram schematically showing reflected waves of ultrasound received by the receiving section of the ultrasound unit shown in FIG. FIG. 5 is a diagram showing an example of an image of the back surface of the workpiece generated by the control unit of the machined groove detection device of the cutting device shown in FIG. FIG. 6 is a perspective view showing a configuration example of a machined groove detection device according to the second embodiment.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Modes (embodiments) for carrying out the present invention will be described in detail with reference to the drawings. The present invention is not limited to the contents described in the following embodiments. Further, 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 configurations described below can be combined as appropriate. Further, various omissions, substitutions, or changes in the configuration can be made without departing from the gist of the present invention.

[Embodiment 1]
A machined groove detection device and a cutting device according to Embodiment 1 of the present invention will be described based on the drawings. First, the configuration of the cutting device 1 will be explained. FIG. 1 is a perspective view showing a configuration example of a cutting device according to a first embodiment. FIG. 2 is a cross-sectional view showing a state in which the machined groove detection device of the cutting apparatus shown in FIG. 1 detects a machined groove. FIG. 3 is a diagram schematically showing the configuration of a main part of the machined groove detection device of the cutting device shown in FIG. 1. As shown in FIG. FIG. 4 is a diagram schematically showing reflected waves of ultrasound received by the receiving section of the ultrasound unit shown in FIG. FIG. 5 is a diagram showing an example of an image of the back surface of the workpiece generated by the control unit of the machined groove detection device of the cutting device shown in FIG.

(Workpiece)
The workpiece 200 to be processed by the cutting apparatus 1 according to the first embodiment is a wafer such as a disk-shaped semiconductor wafer or an optical device wafer, which has a base material of silicon, gallium arsenide, SiC (silicon carbide), or sapphire. It is. Devices 203 are formed on the workpiece 200 in areas partitioned in a grid pattern by a plurality of dividing lines 202 formed in a grid pattern on the surface 201 .

Further, the workpiece 200 of the present invention may be a so-called TAIKO (registered trademark) wafer having a thinner central portion and a thicker portion formed on the outer periphery. A resin package substrate such as a rectangular QFN (Quad Flat No leaded) package substrate having a plurality of , a ceramic substrate, a ferrite substrate, a substrate containing at least one of nickel and iron, a glass substrate, etc. may be used. In the first embodiment, the workpiece 200 is supported by the annular frame 205 with the back surface 204 attached to a dicing tape 206 having an annular frame 205 attached to the outer peripheral edge.

(Cutting device)
The cutting device 1 shown in FIG. 1 holds a workpiece 200 on a holding surface 11 of a chuck table 10 and performs cutting (corresponding to machining) with a cutting blade 21 along a planned dividing line 202. This is a processing device that forms cutting grooves 207 (shown in FIG. 2), which are processing grooves that divide a workpiece 200 into individual devices 203 along lines 202. As shown in FIG. 1, the cutting device 1 is a cutting unit that includes a processing groove detection device 2, which is a detection means for detecting a cutting groove 207 formed by a cutting unit 20, and a cutting blade 21 that cuts a workpiece 200. 20, and an imaging unit (not shown) that photographs the workpiece 200.

The machined groove detection device 2 detects the cutting grooves 207 formed by the cutting unit 20 in the workpiece 200 to which the dicing tape 206 is attached to the back surface 204 side. Further, the machined groove detection device 2 detects the state of both ends of the cutting groove 207 of the workpiece 200 on the back surface 204 side. As shown in FIG. 1, the machined groove detection device 2 includes a chuck table 10, which is a holding means for sucking and holding a workpiece 200 on a holding surface 11, an ultrasonic transducer 30, a moving unit 40, and a water layer forming means. It includes a water layer forming unit 50, which is a water layer forming unit, and a control unit 100, which is an imaging unit.

The chuck table 10 has a disk shape, and a holding surface 11 for holding a workpiece 200 is made of porous ceramic or the like. Furthermore, the chuck table 10 is moved by the X-axis moving unit 41 of the moving unit 40 between a processing area below the cutting unit 20 and a loading/unloading area where the workpiece 200 is loaded/unloaded at a distance from below the cutting unit 20. By being provided movably in the X-axis direction parallel to the horizontal direction.

The chuck table 10 is rotatably provided around an axis parallel to the Z-axis direction by a rotational movement unit 44 of a movement unit 40. In the chuck table 10, the holding surface 11 is connected to a vacuum suction source (not shown), and the holding surface 11 is suctioned by the vacuum suction source, thereby suctioning and holding the workpiece 200 placed on the holding surface 11. In the first embodiment, the chuck table 10 sucks and holds the back surface 204 side of the workpiece 200 via the dicing tape 206 . Further, around the chuck table 10, as shown in FIG. 1, a plurality of clamp parts 12 for clamping the annular frame 205 are provided.

The cutting unit 20 is a cutting means in which a cutting blade 21 for cutting a workpiece 200 held on the chuck table 10 is rotatably attached to the tip of a spindle 23 . The cutting unit 20 is provided so as to be movable in the Y-axis direction with respect to the workpiece 200 held on the chuck table 10 by the Y-axis moving unit 42 of the moving unit 40, and is movable in the Y-axis direction with respect to the workpiece 200 held on the chuck table 10. 43 so as to be movable in the Z-axis direction.

As shown in FIG. 1, the cutting unit 20 is provided on a support frame 4 that stands up from the apparatus main body 3 via a Y-axis moving unit 42, a Z-axis moving unit 43, and the like. The cutting unit 20 is capable of positioning the cutting blade 21 at any position on the holding surface 11 of the chuck table 10 using the Y-axis moving unit 42 and the Z-axis moving unit 43.

The cutting unit 20 includes a cutting blade 21, a spindle housing 22 provided movably in the Y-axis direction and the Z-axis direction by a Y-axis movement unit 42 and a Z-axis movement unit 43, and a spindle housing 22 that rotates about an axis in the spindle housing 22. The spindle 23 is rotatable by a motor (not shown) and has a cutting blade 21 attached to its tip.

The cutting blade 21 is an extremely thin cutting whetstone having a substantially ring shape. In the first embodiment, the cutting blade 21 is a so-called hub blade that includes an annular circular base and an annular cutting blade that is disposed on the outer peripheral edge of the circular base and cuts the workpiece 200. The cutting blade is made of abrasive grains such as diamond or CBN (Cubic Boron Nitride) and a bond material (binding material) such as metal or resin, and is formed to a predetermined thickness. Note that, in the present invention, the cutting blade 21 may be a so-called washer blade composed of only a cutting blade. The spindle 23 rotates the cutting blade 21 by being rotated around its axis by a motor. Note that the axes of the cutting blade 21 and spindle 23 of the cutting unit 20 are set parallel to the Y-axis direction. The cutting unit 20 divides the workpiece 200 into individual devices 203 by cutting the workpiece 200 into individual devices 203 by cutting the cutting blade 21 along the dividing line 202 from the surface 201 side of the workpiece 200 until reaching the dicing tape 206 .

The imaging unit includes an imaging element that photographs the region to be divided of the workpiece 200 held on the chuck table 10 before cutting. The image sensor is, for example, a CCD (Charge-Coupled Device) image sensor or a CMOS (Complementary MOS) image sensor. The imaging unit photographs the workpiece 200 held on the chuck table 10, obtains an image for performing alignment to align the workpiece 200 and the cutting blade 21, and controls the obtained image. Output to unit 100.

The ultrasonic transducer 30 is fixed to the cutting unit 20 so as to move integrally with the cutting unit 20. The ultrasonic transducer 30 has a distal end surface 31 shown in FIG. 3 facing the holding surface 11 of the chuck table 10.The ultrasonic transducer 30 has a top end surface 31 shown in FIG. A piezoelectric vibrator is provided for transmitting ultrasonic waves 300 from the distal end surface 31.

In the ultrasonic transducer 30, the tip surface 31 is formed into a spherical shape in order to converge the ultrasonic waves 300 emitted from the tip surface 31. It may also include a lens. Further, in the embodiment, the diameter of the spot of the ultrasonic waves 300 converged by the ultrasonic transducer 30 is about 10 μm. Further, the ultrasonic transducer 30 receives reflected waves 301 of the ultrasonic waves 300.

The water layer forming unit 50 forms a water layer 51 (shown in FIG. 2) made of pure water between the surface 201 of the workpiece 200 held on the chuck table 10 and the tip surface 31 of the ultrasonic transducer 30. It is something that forms. In the first embodiment, the water layer forming unit 50 is fixed to the cutting unit 20 together with the ultrasonic transducer 30, the opening at the tip is aligned with the tip surface 31 of the ultrasonic transducer 30 in the X-axis direction, and the water layer forming unit 50 is connected to a pure water supply source (not shown). A pure water supply pipe 52 is provided to which pure water is supplied from. The opening at the tip of the pure water supply pipe 52 is arranged next to the tip surface 31 of the ultrasonic transducer 30 in the X-axis direction. The water layer forming unit 50 includes a surface 201 of a workpiece 200 held on the holding surface 11 of the chuck table 10 and a tip surface of the ultrasonic transducer 30 when the ultrasonic transducer 30 irradiates ultrasonic waves 300 from the tip surface 31. 31 to form a water layer 51 therebetween.

The moving unit 40 moves the chuck table 10, the cutting unit 20, and the ultrasonic transducer 30 relative to each other in the X-axis direction and the Y-axis direction, which are directions parallel to the surface 201 of the workpiece 200 held on the holding surface 11. It is a means of transportation. The moving unit 40 includes an X-axis moving unit 41 which is a processing feed unit that processes and feeds the chuck table 10 in the X-axis direction, and indexes and feeds the cutting unit 20 and the ultrasonic transducer 30 in the Y-axis direction perpendicular to the X-axis direction. The Y-axis moving unit 42 is an indexing feed unit, and the cutting feed unit feeds the cutting unit 20 and the ultrasonic transducer 30 in the Z-axis direction, which is parallel to the vertical direction and perpendicular to both the X-axis direction and the Y-axis direction. It includes at least a certain Z-axis moving unit 43 and a rotational moving unit 44 that rotates the chuck table 10 around an axis parallel to the Z-axis direction.

The X-axis moving unit 41 moves the chuck table 10 and the rotational movement unit 44 in the X-axis direction, which is the processing feed direction, thereby moving the chuck table 10, the cutting unit 20, and the ultrasonic transducer 30 relative to each other in the X-axis direction. move it to The Y-axis moving unit 42 moves the cutting unit 20 and the ultrasonic transducer 30 in the Y-axis direction, which is the indexing and feeding direction, thereby moving the chuck table 10, the cutting unit 20, and the ultrasonic transducer 30 relative to each other in the Y-axis direction. move it to

The Z-axis moving unit 43 moves the cutting unit 20 and the ultrasonic transducer 30 in the Z-axis direction, which is the cutting feed direction, thereby moving the chuck table 10, the cutting unit 20, and the ultrasonic transducer 30 relative to each other in the Z-axis direction. move it to The rotational movement unit 44 supports the chuck table 10 and rotates around its axis, and also moves in the X-axis direction together with the chuck table 10 by the X-axis movement unit 41.

The X-axis moving unit 41, the Y-axis moving unit 42, and the Z-axis moving unit 43 include a known ball screw rotatably provided around the axis, a known motor that rotates the ball screw around the axis, and the chuck table 10. Alternatively, a well-known guide rail that supports the cutting unit 20 and the ultrasonic transducer 30 movably in the X-axis direction, Y-axis direction, or Z-axis direction is provided.

The cutting device 1 also includes an X-axis position detection unit (not shown) for detecting the position of the chuck table 10 in the X-axis direction, and a unit (not shown) for detecting the positions of the cutting unit 20 and the ultrasonic transducer 30 in the Y-axis direction. and a Z-axis position detection unit for detecting the positions of the cutting unit 20 and the ultrasonic transducer 30 in the Z-axis direction. The X-axis direction position detection unit and the Y-axis direction position detection unit can be configured by a linear scale parallel to the X-axis direction or the Y-axis direction and a reading head. The Z-axis position detection unit detects the position of the cutting unit 20 in the Z-axis direction using motor pulses. The X-axis position detection unit, the Y-axis position detection unit, and the Z-axis position detection unit control the positions of the chuck table 10 in the X-axis direction and the cutting unit 20 and the ultrasonic transducer 30 in the Y-axis direction or Z-axis direction. Output to unit 100. In the first embodiment, the positions of the chuck table 10, cutting unit 20, and ultrasonic transducer 30 of the cutting device 1 in the X-axis direction, Y-axis direction, and Z-axis direction are based on predetermined reference positions (not shown). determined.

The control unit 100 includes a pulse generating section 101, a receiving section 102, and an imaging section 103, as shown in FIGS. 1 and 3. The pulse generator 101 generates a pulsed voltage having the above-mentioned frequency, and applies the generated pulsed voltage to the piezoelectric vibrator of the ultrasonic transducer 30 to generate the workpiece 200 held on the holding surface 11. Ultrasonic waves 300 are emitted from the tip surface 31 of the ultrasonic transducer 30, which faces the surface 201 of the ultrasonic transducer 30. The ultrasonic wave 300 emitted from the tip surface 31 passes through the water layer 51 formed by the water layer forming unit 50. In this way, as shown in FIG. It constitutes an ultrasonic generation unit 32 that emits ultrasonic waves 300.

The receiving unit 102 generates a voltage according to a reflected wave 301 (shown in FIGS. 2 and 4) of the ultrasonic wave 300 transmitted from the tip surface 31 of the ultrasonic transducer 30 of the ultrasonic generation unit 32 and received from the ultrasonic transducer 30. A signal is received from the ultrasound transducer 30, the received voltage signal is amplified, and is output to the imaging unit 103. Note that the ultrasonic waves 300 emitted from the tip surface 31 and transmitted through the water layer 51 are reflected at interfaces where the acoustic impedance changes, and the intensity of the reflected waves 301 becomes stronger as the difference in acoustic impedance increases.

In the first embodiment, the ultrasonic waves 300 are applied to the front surface 201 of the workpiece 200, which is the interface between the water layer 51 and the workpiece 200, and the back surface of the workpiece 200, which is the interface between the workpiece 200 and the dicing tape 206. reflected from 204. As shown in FIG. 4, the ultrasonic transducer 30 generates reflected waves 301 (hereinafter referred to as 301-1) from the front surface 201 of the ultrasonic waves 300 and reflected waves 301 (hereinafter referred to as 301-1) from the back surface 204 of the ultrasonic waves 300. 301-2) is received. Note that the horizontal axis in FIG. 4 indicates the time that has elapsed since the ultrasonic transducer 30 transmitted the ultrasonic wave 300, and indicates that the time elapses toward the right side in the figure. Further, the vertical axis in FIG. 4 indicates the intensity of the reflected wave 301 received by the ultrasonic transducer 30, and indicates that the intensity increases toward the upper side in the figure.

The receiving unit 102 receives a voltage signal corresponding to a reflected wave 301-1 of the ultrasonic wave 300 from the front surface 201 of the workpiece 200 and a voltage signal corresponding to the reflected wave 301-2 of the ultrasonic wave 300 from the back surface 204 of the workpiece 200. The ultrasonic transducer 30 receives a voltage signal from the ultrasonic transducer 30 . In this way, the ultrasonic transducer 30 and the receiving unit 102 receive the reflected wave 301 of the ultrasonic wave 300 reflected from the workpiece 200 held on the chuck table 10 via the dicing tape 206, as shown in FIG. This constitutes an ultrasonic receiving unit 33 that performs the following steps. Further, the ultrasonic generation unit 32 and the ultrasonic reception unit 33 constitute an ultrasonic unit 34, as shown in FIG. For this reason, the machined groove detection device 2 according to the first embodiment includes an ultrasonic unit 34.

The imaging unit 103 images the reflected wave 301 of the ultrasonic wave 300 received by the ultrasonic receiving unit 33 from the back surface 204 side of the workpiece 200 as a light and dark image depending on the intensity. That is, the control unit 100 including the imaging section 103 converts the reflected waves 301 of the ultrasonic waves 300 from the back surface 204 side of the workpiece 200 received by the ultrasonic receiving unit 33 into an image as shading according to the intensity. unit. The imaging unit 103 images the reflected wave 301 as a light and dark image according to the intensity, and forms an image 400 shown in FIG. 5 . Imaging section 103 receives the voltage signal from receiving section 102 . Note that the voltage signal received by the imaging unit 103 from the receiving unit 102 has a voltage value defined by a plurality of gradations (for example, 256 levels). The voltage value of the voltage signal received by the imaging unit 103 from the receiving unit 102 is defined in stages according to the intensity of the reflected wave 301, and the stronger the intensity of the reflected wave 301, the higher the voltage value and the higher the intensity of the reflected wave 301. The weaker the voltage, the lower the voltage value specified. The imaging unit 103 calculates the voltage value of the voltage signal at each position in the X-axis direction and the Y-axis direction of the workpiece 200 based on the voltage signal received from the reception unit 102 and the detection results of each position detection unit. An image 400 showing strength and weakness as shading, that is, an image 400 having shading is formed. In the first embodiment, in the image 400, positions where the voltage value is high are displayed lighter than positions where the voltage value is weak. In FIG. 5, the shading of the image 400 is omitted.

The machined groove detection device 2 separates the workpiece 200 and the ultrasonic transducer 30 in a state where a water layer 51 is formed between the surface 201 of the workpiece 200 on which the cutting groove 207 is formed and the tip surface 31. By emitting ultrasonic waves 300 from the tip surface 31 of the ultrasonic transducer 30 while relatively moving along the planned line 202 and receiving reflected waves of the ultrasonic waves 300, the imaging unit 103 images the workpiece 200. An image 400 including each cut groove 207 on the back surface 204 side is generated, and the state of both edges of the cut groove 207 on the back surface 204 side is detected.

Further, the control unit 100 controls each component of the cutting device 1 and the machined groove detection device 2 to cause the cutting device 1 to perform a machining operation on the workpiece 200, and also controls the cutting device 1 to perform a machining operation on the workpiece 200. This is to cause the machined groove detection device 2 to perform an operation of detecting the state of both edges on the 204 side. Note that the control unit 100 includes an arithmetic processing device having a microprocessor such as a CPU (central processing unit), a storage device having a memory such as a ROM (read only memory) or a RAM (random access memory), and an input/output unit. A computer having an interface device. The arithmetic processing device of the control unit 100 performs arithmetic processing according to the computer program stored in the storage device, and sends control signals for controlling the cutting device 1 and the machined groove detection device 2 via the input/output interface device. and outputs to each component of the cutting device 1 and the machined groove detection device 2.

Note that the functions of the pulse generating section 101, the receiving section 102, and the imaging section 103 are realized by the arithmetic processing device executing a computer program stored in a storage device. Further, in the present invention, the pulse generating section 101, the receiving section 102, and the imaging section 103 are dedicated processing circuits (hardware) such as a single circuit, a composite circuit, a programmed processor, or a parallel programmed processor. may be configured. In particular, the pulse generating section 101 and the receiving section 102 may be constituted by a dedicated processing circuit (hardware) such as a single programmed processor.

The control unit 100 includes a display unit 110 that includes a liquid crystal display device that displays the status of machining operations, images, etc., an input unit 111 that is used by the operator to register machining content information, and a notification unit that notifies the operator. 112. The input unit 111 includes at least one of a touch panel provided on the display unit 110 and an external input device such as a keyboard. The notification unit 112 notifies the operator by emitting at least one of sound and light.

The cutting device 1 according to the first embodiment also includes a cleaning unit 60 that cleans the workpiece 200 after cutting, and a transport unit (not shown) that transports the workpiece 200 between the chuck table 10 and the cleaning unit 60. The cleaning unit 60 includes a spinner table 61, which is a holding means for suctioning and holding the workpiece 200 via a dicing tape 206, and a surface 201 side of the workpiece 200, which is suctioned and held by the spinner table 61, which rotates around the axis. A cleaning liquid supply nozzle 62 for supplying cleaning liquid for cleaning is provided.

(Processing operation of cutting device)
When starting the machining operation of the cutting device 1, the operator registers machining content information in the control unit 100 and places the workpiece 200 to be cut on the holding surface 11 of the chuck table 10. Thereafter, the cutting device 1 starts the machining operation when the operator gives an instruction to start the machining operation. When the cutting device 1 starts the machining operation, the back surface 204 side is held by suction to the holding surface 11 of the chuck table 10 via the dicing tape 206, and the annular frame 205 is clamped by the clamp portion 12.

In the machining operation, in the cutting device 1, the X-axis moving unit 41 moves the chuck table 10 toward the machining area, the imaging unit photographs the workpiece 200, and the image taken by the imaging unit is converted into an image. Perform alignment based on this. The cutting device 1 moves the workpiece 200 and the cutting unit 20 relatively along the dividing line 202, and cuts the cutting blade 21 into each dividing line 202 until it reaches the dicing tape 206. , cutting grooves 207 are formed in the workpiece 200 along the dividing line 202 to divide the workpiece 200 into individual devices 203. Note that when forming the cutting groove 207, the cutting device 1 creates chips (also referred to as chipping) 208 and 208 on both edges of the cutting groove 207 on the front surface 201 and back surface 204 of the workpiece 200, respectively, as shown in FIG. Cracks 209 may be formed. Note that FIG. 5 shows a chip 208 and a crack 209 formed on both edges of the cutting groove 207 on the back surface 204 side.

The cutting device 1 forms cutting grooves 207 on all of the planned division lines 202, and when the workpiece 200 is divided into individual devices 203, the cutting groove detection device 2 detects the cutting grooves 207 on the back surface 204 side of the workpiece 200. Detect the state of both edges. In the cutting device 1, the processing groove detection device 2 uses an The transducer 30 is positioned, and the Z-axis moving unit 43 positions the ultrasonic transducer 30 at a position in the Z-axis direction where the ultrasonic waves 300 emitted from the distal end surface 31 converge on the back surface 204 . In the cutting device 1, the machined groove detection device 2 detects the surface 201 of the workpiece 200 held on the chuck table 10 and the tip surface 31 of the ultrasonic transducer 30 from the opening at the tip of the pure water supply pipe 52 of the water layer forming unit 50. Pure water is supplied between the two to form a water layer 51.

In the cutting device 1, the processing groove detection device 2 moves the workpiece 200 and the ultrasonic transducer 30 relatively along the dividing line 202 using the X-axis moving unit 41 and the Y-axis moving unit 42, while detecting the tip end surface. 31 emits an ultrasonic wave 300, the ultrasonic transducer 30 receives a reflected wave 301, and detects the state of the back surface 204 side of each scheduled dividing line 202. In the first embodiment, when detecting the state of the back surface 204 side of one planned dividing line 202, the cutting device 1 transmits an ultrasonic wave 300 and moves along each scheduled dividing line 202 while receiving reflected waves 301. Moving the ultrasonic transducer 30 over the entire length in the X-axis direction and moving the ultrasonic transducer 30 a predetermined distance in the Y-axis direction with respect to each division line 202 are repeated multiple times, and the workpiece 200 is The reflected wave 301 from the back surface 204 of is received.

In Embodiment 1, the imaging unit 103 of the machined groove detection device 2 uses the detection result of each position detection unit and the voltage signal of the reflected wave 301 received and amplified by the reception unit 102 to generate an image, an example of which is shown in FIG. An image 400 is generated. In the first embodiment, the imaging unit 103 forms an image 400 having gradation that becomes brighter as the voltage signal of the reflected wave 301 becomes higher and darker as the voltage signal becomes lower. That is, the image 400 is an image whose density changes depending on the intensity of the reflected wave 301 of the ultrasonic wave 300 on the back surface 204 side of the workpiece 200. In addition, the ultrasonic wave 300 is reflected at an interface where the acoustic impedance changes, and the intensity of the reflected wave 301 becomes stronger as the difference in acoustic impedance increases. The reflected wave 301 from the crack 209 becomes stronger. Therefore, the image 400 formed by the imaging unit 103 displays the chip 208 and the crack 209 brighter than other parts.

After forming an image 400 including both edges of the cutting groove 207 on the back surface 204 side of all the planned dividing lines 202 of the workpiece 200, the machined groove detection device 2 stores the formed image 400 in a storage device, and Detection of the state of both edges of the cutting groove 207 on the back surface 204 side of the workpiece 200 is completed. In the first embodiment, the machined groove detection device 2 stores the formed image 400 in the storage device in association with the workpiece 200. In this way, in the machined groove detection device 2, the ultrasonic transducer 30 of the ultrasonic generation unit 32 emits ultrasonic waves 300 such that the ultrasonic waves 300 converge on the back surface 204 side of the cutting groove 207 formed in the workpiece 200. Then, the imaging unit 103 forms an image 400 whose density changes based on the intensity of the reflected wave 301 of the ultrasonic wave 300 on the back surface 204 side of the workpiece 200, and forms an image 400 that changes in density based on the intensity of the reflected wave 301 of the ultrasonic wave 300 on the back surface 204 side of the workpiece 200. Detect conditions.

The control unit 100 of the machined groove detection device 2 according to the first embodiment displays the formed image 400 on the display unit 110, receives an operator's operation from the input unit 111, and displays the workpiece 200 displayed on the display unit 110. You may change the position of. In addition, the control unit 100 of the machined groove detection device 2 according to the first embodiment extracts chips 208 and cracks 209 from the formed image 400, and determines whether each workpiece 200 is good or bad based on their sizes. You can judge. Furthermore, if the workpiece 200 is determined to be defective, the notification unit 112 may be activated to notify the operator.

When the cutting device 1 finishes detecting the state of both edges of the cutting groove 207 on the back surface 204 side of the workpiece 200, the cutting device 1 moves the workpiece 200 divided into individual devices 203 toward the loading/unloading area. , the suction holding of the holding surface 11 and the clamping of the clamp part 12 are released in the loading/unloading area. After the cutting device 1 transports the workpiece 200 to the cleaning unit 60 by the transport unit, the processing operation ends.

As described above, the machined groove detection device 2 according to the first embodiment includes the chuck table 10 that holds the workpiece 200 and the ultrasonic waves 300 that are transmitted to the workpiece and reflected from the workpiece 200. An ultrasonic unit 34 that receives a reflected wave 301 of an ultrasonic wave 300, a moving unit 40 that relatively moves the chuck table 10 and the ultrasonic transducer 30 in the X-axis direction and the Y-axis direction, and a water layer forming unit 50. Equipped with Therefore, the machining groove detection device 2 forms a water layer 51 between the workpiece 200 and the tip surface 31 of the ultrasonic transducer 30, and aligns the chuck table 10 and the ultrasonic transducer 30 to the planned dividing line 202. The intensity of the reflected wave 301 of the ultrasonic wave 300 from the back surface 204 of the workpiece 200 can be obtained by transmitting the ultrasonic wave 300 and receiving the reflected wave 301 while moving the object 200 relatively.

Further, the machined groove detection device 2 includes an imaging unit 103 that forms an image 400 having shading according to the intensity and images the intensity of the reflected wave 301 of the ultrasonic wave 300. Chips 208 and cracks 209 occurring on both side edges can be seen. As a result, the machined groove detection device 2 detects the chipping that has occurred on both edges of the cutting groove 207 on the back surface 204 side of the workpiece 200 while the workpiece 200 is being suctioned and held on the chuck table 10 via the dicing tape 206. Since the chips 208 and cracks 209 can be detected, the number of man-hours required for observing the back surface 204 can be reduced, and the chips 208 and cracks 209 on the back surface 204 of the workpiece 200 can be easily detected.

Furthermore, since the cutting device 1 according to the first embodiment includes the above-described machining groove detection device 2, the workpiece 200 can be cut while the workpiece 200 is being suctioned and held on the chuck table 10 via the dicing tape 206. Chips 208 and cracks 209 occurring on both edges of the groove 207 on the back surface 204 side can be detected, and chips 208 and cracks 209 on the back surface 204 side of the workpiece 200 can be easily detected.

[Embodiment 2]
A machined groove detection device according to a second embodiment of the present invention will be described based on the drawings. FIG. 6 is a perspective view showing a configuration example of a machined groove detection device according to the second embodiment. In addition, in FIG. 6, the same parts as those in Embodiment 1 are given the same reference numerals, and the description thereof will be omitted.

As shown in FIG. 6, the machined groove detection device 2-2 according to the second embodiment includes a chuck table 10, an ultrasonic unit 34, a moving unit 40, and the like, without being included in a processing device such as the cutting device 1. It includes a water layer forming unit 50 and an imaging section 103. In the machined groove detection device 2-2 according to the second embodiment, the water layer forming unit 50 forms a water layer 51 between the workpiece 200 and the tip surface 31 of the ultrasonic transducer 30, and the moving unit 40 The ultrasonic unit 34 emits ultrasonic waves 300 and receives reflected waves 301 while moving the table 10 and the ultrasonic transducer 30 relative to the planned dividing line 202, so that ultrasonic waves from the back surface 204 of the workpiece 200 are The intensity of the reflected wave 301 of the sound wave 300 is acquired.

The machined groove detection device 2-2 according to the second embodiment detects both edges of the cutting groove 207 of the workpiece 200 on the back surface 204 side while the workpiece 200 is suctioned and held on the chuck table 10 via the dicing tape 206. The chips 208 and cracks 209 that have occurred on the back surface 204 of the workpiece 200 can be easily detected, similar to the first embodiment.

Note that the present invention is not limited to the above embodiments. That is, various modifications can be made without departing from the gist of the invention. In addition, in the above-mentioned Embodiment 1, an example is shown in which the cutting device 1 is equipped with the machining groove detection device 2 as a machining device, but in the present invention, the machining device equipped with the machining groove detection device 2 is limited to the cutting device 1. Instead, for example, a laser processing apparatus may be used that processes the workpiece 200 with a laser beam (ablation process) by irradiating the workpiece 200 with a laser beam having an absorbing wavelength. That is, the processed groove detection device 2 of the present invention is not limited to the cut groove 207 as the processed groove, and may detect, for example, a laser processed groove. Further, in the present invention, the machining groove detection device 2 is not limited to detecting the machining groove of the workpiece 200 that is suction-held on the chuck table 10; The machined grooves of the workpiece 200 after cleaning may also be detected. Further, in the present invention, the ultrasonic unit 34 arranges a plurality of ultrasonic transducers 30 in the Y-axis direction, and moves the plurality of ultrasonic transducers 30 once in the X-axis direction relative to each dividing line 202. In this way, the chips 208 and cracks 109 on both edges of the cut groove 207 on the back surface 204 side may be detected.

1 Cutting equipment (processing equipment)
2,2-2 Machining groove detection device (detection means)
10 Chuck table (holding means)
20 Cutting unit (cutting means)
21 cutting blade 32 ultrasonic generating unit 33 ultrasonic receiving unit 34 ultrasonic unit 40 moving unit (moving means)
50 Water layer forming unit 51 Water layer 100 Control unit (imaging unit)
200 Workpiece 201 Front surface 204 Back surface 206 Dicing tape 207 Cutting groove (processing groove)
300 Ultrasonic waves 301, 301-1, 301-2 Reflected waves X, Y Direction parallel to the surface

Claims (3)

A machined groove detection device that detects a machined groove formed in a workpiece to which a dicing tape is attached on the back side,
holding means for holding the workpiece;
an ultrasonic generation unit that transmits ultrasonic waves to the workpiece from the surface side of the workpiece held by the holding means via the dicing tape; an ultrasonic unit equipped with an ultrasonic receiving unit that receives reflected waves);
moving means for relatively moving the holding means and the ultrasonic unit in a direction parallel to the surface of the workpiece;
water layer forming means for forming a water layer between the workpiece and the ultrasonic unit;
an imaging unit that creates an image as light and dark depending on the intensity of the reflected wave received by the ultrasound receiving unit;
including;
While the moving means relatively moves the workpiece in which the processing groove is formed and the ultrasonic unit along the planned dividing line,
The ultrasonic generation unit transmits ultrasonic waves so that the ultrasonic waves converge on the back side of the processing groove formed in the workpiece,
Generating an image including the processed groove on the back side of the workpiece based on the reflected wave intensity of the ultrasonic wave on the back side of the workpiece, and detecting the state of both edges of the back side of the processed groove. A machined groove detection device characterized by: a chuck table that holds the workpiece;
a cutting means equipped with a cutting blade for cutting the workpiece held on the chuck table;
detection means for detecting a cutting groove formed by the cutting means;
A cutting device comprising:
A cutting device, wherein the detection means is the machined groove detection device according to claim 1. The cutting device according to claim 2, wherein the chuck table is the holding means according to claim 1.

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