JP4847069B2 - Cutting equipment - Google Patents

Description

  The present invention relates to a cutting apparatus that applies ultrasonic vibration to a cutting blade to cut a workpiece such as a semiconductor wafer or an optical device wafer.

  In the semiconductor device manufacturing process, a plurality of regions are partitioned by dividing lines called streets arranged in a lattice pattern on the surface of a substantially wafer-shaped semiconductor wafer, and devices such as ICs, LSIs, etc. are partitioned in the partitioned regions. Form. Then, the semiconductor wafer is cut along the streets to divide the region in which the device is formed to manufacture individual semiconductor chips. In addition, optical device wafers with gallium nitride compound semiconductors laminated on the surface of sapphire substrates are divided into individual light emitting diodes, laser diodes, CCDs and other optical devices by cutting along the streets. It's being used.

  The above-described cutting along the wafer street is usually performed by a cutting device called a dicer. This cutting apparatus includes a chuck table for holding a workpiece such as a wafer, a cutting means for cutting the workpiece held on the chuck table, and a cutting for relatively moving the chuck table and the cutting means. And feeding means. The cutting means includes a spindle unit having a rotary spindle, a cutting blade mounted on the spindle, and a drive mechanism for driving the rotary spindle to rotate. In such a cutting apparatus, the workpiece held on the cutting blade and the chuck table is relatively cut and fed while rotating the cutting blade at a rotational speed of 20000 to 40000 rpm.

  However, brittle hard materials such as silicon, sapphire, silicon nitride, glass and lithium tantalate are used for the wafer on which the device is formed. There is a problem of lowering. Also, a wafer with high Mohs hardness such as sapphire is very difficult if not impossible to cut with a cutting blade.

In order to solve the above-described problems, an ultrasonic vibrator is disposed on a rotating spindle on which a cutting blade is mounted, and an ultrasonic voltage is applied to the cutting blade by applying an AC voltage to the ultrasonic vibrator. There has been proposed a cutting apparatus that performs cutting. (For example, refer to Patent Document 1.)
In addition, a cutting apparatus has been proposed in which an ultrasonic vibrator is fixed to the surface of the cutting blade and an AC voltage is applied to the ultrasonic vibrator to perform cutting while applying ultrasonic vibration to the cutting blade. Yes. (For example, refer to Patent Document 3.)
JP-A 63-139649 Japanese Patent Laid-Open No. 2004-291636

  Thus, it is necessary to adjust the amplitude of the ultrasonic vibration applied to the cutting blade according to the processing conditions such as the material of the wafer as the workpiece, the cutting depth, the cutting feed rate, the cutting water supply condition, and the like. Therefore, it is desirable that the amplitude of the ultrasonic vibration applied to the cutting blade can be easily detected.

  The present invention has been made in view of the above facts, and its main technical problem is to provide a cutting apparatus provided with an amplitude detecting means capable of detecting the amplitude of ultrasonic vibration applied to a cutting blade. It is in.

In order to solve the main technical problem, a chuck table mechanism having a chuck table for holding a workpiece, a cutting means having a cutting blade for cutting the workpiece held on the chuck table, and the cutting blade A cutting apparatus comprising: an ultrasonic vibrator for applying ultrasonic vibration to the power supply means; a power supply means for applying AC power to the ultrasonic vibrator ; and a control means for controlling the power supply means .
And it includes the amplitude detection means for detecting the amplitude of the radial the cutting blade,
The amplitude detecting means includes a light emitting means and a light receiving means which are provided on the chuck table mechanism and face each other, and a blade receiving portion which is formed between the light emitting means and the light receiving means and receives the outer periphery of the cutting blade. A photoelectric conversion means for converting the amount of light received by the light receiving means of the detector into a voltage signal, and a maximum value and a minimum value of the voltage value output from the photoelectric conversion means. An amplitude determination means for obtaining a radial amplitude,
When the radial amplitude of the cutting blade determined by the amplitude determining means deviates from the set amplitude set corresponding to the processing conditions of the workpiece, the control means There is provided a cutting device characterized in that the AC power applied is controlled to adjust the amplitude of the cutting blade to the set amplitude .

The photoelectric conversion means sends a voltage corresponding to the amount of light transmitted through the light receiving means to the amplitude determination means, and the amplitude determination means has a voltage outputted from the outer peripheral position of the cutting blade and the photoelectric conversion means. It is preferable that reference data in which a relationship with a value is set is input.

  Since the cutting apparatus according to the present invention includes amplitude detection means for detecting the amplitude in the radial direction of the ultrasonic vibration applied to the cutting blade, the ultrasonic vibration applied to the cutting blade corresponding to the processing conditions. The amplitude in the radial direction can be adjusted accurately.

  Hereinafter, a preferred embodiment of a cutting device configured according to the present invention will be described in more detail with reference to the accompanying drawings.

  FIG. 1 shows a perspective view of a cutting device constructed in accordance with the present invention. The cutting device in the illustrated embodiment includes a device housing 2 having a substantially rectangular parallelepiped shape. In the apparatus housing 2, a chuck table mechanism 3 for holding a workpiece is disposed so as to be movable in a direction indicated by an arrow X that is a cutting feed direction. The chuck table mechanism 3 is disposed at a predetermined height below a chuck table 30 including a suction chuck support 31 and a suction chuck 32 disposed on the suction chuck support 31, and an upper surface of the suction chuck 32. The support table 33 is provided, and the workpiece is sucked and held on the holding surface, which is the upper surface of the chuck 32 of the chuck table 30, by operating a suction means (not shown). The chuck table 30 is configured to be rotatable by a rotation mechanism (not shown). The chuck table 30 is provided with a clamp 34 for fixing a support frame for supporting a wafer, which will be described later, as a workpiece through a protective tape. The chuck table mechanism 3 configured as described above can be moved in a cutting feed direction indicated by an arrow X by a cutting feed means (not shown).

  The cutting apparatus in the illustrated embodiment includes a spindle unit 4 as cutting means. The spindle unit 4 is mounted on a moving base (not shown) and is moved in an indexing direction indicated by an arrow Y perpendicular to the cutting feed direction indicated by the arrow X by indexing feeding means (not shown), and a cutting direction by a notch feeding means (not shown). It can be moved in the direction indicated by the arrow Z. The spindle unit 4 will be described with reference to FIG.

  The spindle unit 4 shown in FIG. 2 includes a spindle housing 41, a rotating spindle 42 that is rotatably disposed in the spindle housing 41, and a cutting tool 43 that is attached to the tip of the rotating spindle 42. . The spindle housing 41 is formed in a substantially cylindrical shape and includes a shaft hole 411 penetrating in the axial direction. A rotary spindle 42 that is inserted through a shaft hole 411 formed in the spindle housing 41 includes a tool mounting portion 422 provided with a screw hole 421 at a front end portion thereof, and a central portion thereof in a radial direction. A protruding thrust bearing flange 423 is provided. In this way, the rotary spindle 42 disposed through the shaft hole 411 formed in the spindle housing 41 is rotatably supported by high-pressure air supplied between the inner wall of the shaft hole 411.

  A cutting tool 43 mounted on a tool mounting portion 422 provided at the tip of the rotary spindle 42 includes a resonance member 44 and a cutting blade 45 mounted on the resonance member 44. The resonance member 44 is formed of aluminum in the illustrated embodiment, and has a central large diameter portion 441, a first small diameter portion 442 formed so as to protrude coaxially from one end surface of the central large diameter portion 441, and a large central portion. The second small-diameter portion 443 is formed so as to protrude coaxially from the other end surface of the diameter portion 441. Note that the first small diameter portion 442 and the second small diameter portion 443 are formed to have the same dimensions. A through hole 444 that penetrates the center of the shaft is formed in the resonance member 44 thus formed. In the illustrated embodiment, the cutting blade 45 attached to the resonance member 44 has an electric power obtained by bonding abrasive grains to the end surface of the central large diameter portion 441 of the resonance member 44 on the first small diameter portion 442 side by metal plating such as nickel. It is constituted by a cast blade. The cutting tool 43 configured as described above is configured so that the tightening bolt 46 inserted through the through hole 444 is screwed into the screw hole 421 provided in the tool mounting portion 422 of the rotary spindle 42 to thereby rotate the rotary spindle. 42 is attached. Note that when the cutting tool 43 is mounted on the tool mounting portion 422 of the rotary spindle 42, the tool mounting portion 422 and the first small diameter portion 442 and the second small diameter portion 443 and the head of the tightening bolt 46 are connected. Between the spacers 47 and 47 made of synthetic resin are interposed.

  The spindle unit 4 in the illustrated embodiment includes an electric motor 5 for driving the rotary spindle 42 to rotate. The illustrated electric motor 5 is constituted by a permanent magnet motor. The permanent magnet type electric motor 5 is disposed in a spindle housing 41 on the outer peripheral side of the rotor 51 and a rotor 51 made of a permanent magnet mounted on a motor mounting portion 424 formed in an intermediate portion of the rotary spindle 42. The stator coil 52 is included. In the electric motor 5 configured in this manner, the rotor 51 is rotated by applying AC power to the stator coil 52 by power supply means described later, and the rotating spindle 42 to which the rotor 51 is mounted is rotated.

  The spindle unit 4 in the illustrated embodiment includes an ultrasonic transducer 6 that is disposed on the rotary spindle 42 and applies ultrasonic vibration to the cutting blade 45. The ultrasonic vibrator 6 includes an annular piezoelectric body 61 polarized in the axial direction of the rotary spindle 42 and two annular electrode plates 62 and 63 attached to both side polarization surfaces of the piezoelectric body 61. It has become. The piezoelectric body 61 is made of piezoelectric ceramics such as barium titanate, lead zirconate titanate, and lithium tantalate. The ultrasonic transducer 6 configured as described above is mounted on the rotary spindle 42, and generates ultrasonic vibration when AC power having a predetermined frequency is applied to the electrode plates 62 and 63 by power supply means described later. A plurality of ultrasonic transducers 6 may be arranged in the axial direction.

The spindle unit 4 in the illustrated embodiment includes power supply means 7 that applies AC power to the ultrasonic vibrator 6 and applies AC power to the electric motor 5.
The power supply means 7 includes a rotary transformer 8 disposed at the rear end of the spindle unit 4. The rotary transformer 8 includes a power receiving unit 81 disposed at the rear end of the rotary spindle 42 and a power feeding unit 82 disposed opposite to the power receiving unit 81 and disposed at the rear end portion of the spindle housing 41. is doing. The power receiving means 81 includes a rotor side core 811 attached to the rotary spindle 42 and a power receiving coil 812 wound around the rotor side core 811. One end of the power receiving coil 812 of the power receiving means 81 configured in this way is connected to the electrode plate 61 of the ultrasonic transducer 6, and the other end is connected to the electrode plate 62. The power supply means 82 includes a stator side core 821 disposed on the outer peripheral side of the power reception means 81 and a power supply coil 822 disposed on the stator side core 821. The power supply coil 822 of the power supply means 82 configured in this way is supplied with AC power via the electrical wirings 73 and 74.

  The power supply means 7 in the illustrated embodiment includes an AC power supply 91 for AC power supplied to the power supply coil 822 of the rotary transformer 8, a voltage adjustment means 92 as power adjustment means, and AC power supplied to the power supply means 82. Frequency adjusting means 93 for adjusting the frequency of the power, control means 94 for controlling the voltage adjusting means 92 and the frequency adjusting means 93, and input means 95 for inputting the amplitude of the ultrasonic vibration applied to the cutting blade 45 to the control means. It has. The power supply means 7 shown in FIG. 2 supplies AC power to the stator coil 52 of the electric motor 5 through the control circuit 96 and the electric wirings 521 and 522.

The spindle unit 4 in the illustrated embodiment is configured as described above, and the operation thereof will be described below.
When performing the cutting operation, AC power is supplied from the power supply means 7 to the stator coil 52 of the electric motor 5. As a result, the electric motor 5 rotates and the rotary spindle 42 rotates, and the cutting blade 45 attached to the resonance member 44 of the cutting tool 43 attached to the tip of the rotary spindle 42 is rotated.

  On the other hand, the power supply means 7 controls the voltage adjusting means 92 and the frequency converting means 93 by the control means 94 to control the voltage of the AC power to a predetermined voltage, and the frequency of the AC power is set to a predetermined frequency (for example, 20 kHz). And is supplied to the power supply coil 822 of the power supply means 82 constituting the rotary transformer 8. When AC power having a predetermined frequency is applied to the feeding coil 822 as described above, AC power having a predetermined frequency is interposed between the electrode plate 62 and the electrode plate 63 of the ultrasonic transducer 6 via the power receiving coil 812 of the rotating power receiving means 81. Is applied. As a result, the ultrasonic transducer 6 is repeatedly displaced in the radial direction and vibrates ultrasonically. This ultrasonic vibration is transmitted to the resonance member 44 of the cutting tool 43 via the rotary spindle 42, and the resonance member 44 ultrasonically vibrates in the radial direction. Therefore, the cutting blade 45 mounted on the resonance member 44 vibrates ultrasonically in the radial direction. Note that the amplitude of the ultrasonic vibration applied to the cutting blade 45 is proportional to the amount of AC power applied to the ultrasonic vibrator 6.

  The cutting apparatus in the illustrated embodiment includes amplitude detecting means 10 for detecting the radial amplitude of the cutting blade 45 as shown in FIG. As shown in FIG. 1, the amplitude detecting means 10 includes a detector 11 disposed on a support table 33 of the chuck table mechanism 3. As shown in FIG. 3, the detector 11 includes a detector main body 111, a light emitting means 112 and a light receiving means 113 disposed opposite to the detector main body 111, and between the light emitting means 112 and the light receiving means 113. And a blade receiving portion 114 that receives the outer peripheral portion of the cutting blade 45. The light emitting means 112 is connected to the light source 13 through the optical fiber 12 and emits light from the light source 13 toward the light receiving means 113. The light receiving means 113 receives the light emitted by the light emitting means 112 and sends the received light to the photoelectric conversion means described later via the optical fiber 14.

  The amplitude detection means 10 in the illustrated embodiment includes a photoelectric conversion means 15 that converts the amount of light transmitted from the light receiving means 113 of the detector 11 through the optical fiber 14 into a voltage signal, and the photoelectric conversion means 15 outputs Amplitude determining means 16 for determining the radial amplitude of the cutting blade 45 from the maximum value and the minimum value of the voltage value to be processed. The photoelectric conversion means 15 sends a voltage corresponding to the amount of light sent from the light receiving means 113 via the optical fiber 14 to the amplitude determination means 16. The amplitude determination unit 16 obtains the radial amplitude of the cutting blade 45 from the maximum value and the minimum value of the voltage value output from the photoelectric conversion unit 15. The amplitude determination means 16 is input with reference data 17 in which the relationship between the outer peripheral position (radial displacement amount) of the cutting blade 45 and the voltage value output from the photoelectric conversion means 15 is set. The reference data 17 is set based on a state in which the outer peripheral edge of the cutting blade 45 is positioned on a line passing through the centers of the light emitting means 112 and the light receiving means 113. That is, in the illustrated embodiment, the output voltage value of the photoelectric conversion means 15 in a state where the cutting blade 45 is positioned at the reference position (0) is set to 5V. When the outer peripheral edge of the cutting blade 45 is displaced upward in FIG. 3, the output voltage value of the photoelectric conversion means 15 increases. When the outer peripheral edge of the cutting blade 45 is displaced downward in FIG. 3, the output voltage of the photoelectric conversion means 15. The value is set to decrease.

Next, a procedure (amplitude detection process) for detecting the amplitude of radial vibration applied to the cutting blade 45 using the above-described amplitude detection means 10 will be described.
First, the chuck table mechanism 3 and the spindle unit 4 are operated by cutting feed means and index feed means (not shown) of the cutting apparatus shown in FIG. 1, and the detector 11 disposed on the support table 33 is placed directly below the cutting blade 45. Position. Then, the notch feeding means (not shown) is operated to move the spindle unit 4 and thus the cutting blade 45 downward. At this time, the amplitude detection means 10 shown in FIG. 3 monitors the voltage value output from the photoelectric conversion means 15, and stops the operation of the cutting feed means when the voltage value from the photoelectric conversion means 15 reaches 5V. Then, the lowering of the cutting blade 45 is stopped. Next, AC power is applied to the ultrasonic transducer 6 by operating the power supply means 7 shown in FIG. That is, the power supply means 7 controls the voltage adjusting means 92 and the frequency converting means 93 by the control means 94 to control the voltage of the AC power to a predetermined voltage, and the frequency of the AC power is set to a predetermined frequency (for example, 20 kHz). And is supplied to the power supply coil 822 of the power supply means 82 constituting the rotary transformer 8. When AC power having a predetermined frequency is applied to the feeding coil 822 in this way, an AC voltage having a predetermined frequency is applied between the electrode plate 62 and the electrode plate 63 of the ultrasonic transducer 6 via the power receiving coil 812 of the power receiving means 81. Is done. As a result, the ultrasonic transducer 6 is repeatedly displaced in the radial direction and vibrates ultrasonically. This ultrasonic vibration is transmitted to the resonance member 44 of the cutting tool 43 via the rotary spindle 42, and the resonance member 44 ultrasonically vibrates in the radial direction. Therefore, the cutting blade 45 mounted on the resonance member 44 vibrates ultrasonically in the radial direction. As a result, the cutting blade 45 is displaced in the vertical direction in FIG. When the cutting blade 45 is displaced in the vertical direction in FIG. 2, the amount of light received by the light receiving means 113 changes. Therefore, the photoelectric conversion means 15 generates amplitude data 18 as a voltage signal corresponding to the displacement of the cutting blade 45. Is output. The amplitude determining means 16 having received the amplitude data 18 obtains the maximum value and the minimum value of the voltage value from the amplitude data 18. In the illustrated amplitude data 18, the maximum value is 8V and the minimum value is 2V. Then, the amplitude determination means 16 obtains the radial amplitude of the cutting blade 45 by comparing the maximum value of 8 V and the minimum value of 2 V with the displacement of the cutting blade 45 set in the reference data 17. In the illustrated embodiment, the displacement amount of the maximum value (8V) is 3 μm, and the displacement amount of the minimum value (2V) is −3 μm. Therefore, the amplitude determining means 16 determines the radial amplitude of the cutting blade 45 as 6 μm which is the width between the maximum value and the minimum value. The amplitude determining means 16 sends the determined radial amplitude of the cutting blade 45 to the control means 94 of the power supply means 7.

  Referring back to FIG. 1, the description of the cutting apparatus in the illustrated embodiment is for imaging the surface of the workpiece held on the chuck table 3 and detecting the area to be cut by the cutting blade 45. The alignment means 21 is provided. The alignment unit 21 includes an imaging unit including an optical unit such as a microscope or a CCD camera. In addition, the cutting apparatus includes a display unit 22 that displays an image captured by the alignment unit 21, amplitude data 18 output from the photoelectric conversion unit 15, and the like.

  In the cassette mounting area 23a of the apparatus housing 2, a cassette mounting table 23 for mounting a cassette for storing a workpiece is disposed. The cassette mounting table 23 is configured to be movable in the vertical direction by lifting means (not shown). On the cassette mounting table 23, a cassette 24 for storing the workpiece 200 is mounted. The workpiece 200 accommodated in the cassette 24 has a grid-like street formed on the surface of the wafer, and devices such as capacitors, LEDs, and circuits are formed in a plurality of rectangular areas partitioned by the grid-like street. Has been. The workpiece 200 formed in this way is accommodated in the cassette 14 with the back surface adhered to the front surface of the protective tape 202 attached to the annular support frame 201.

  In the illustrated embodiment, the cutting apparatus is supported by a workpiece 200 (an annular frame 201 supported via a protective tape 202) accommodated in a cassette 24 placed on the cassette placement table 13. ) To the temporary table 25, a conveying unit 27 to convey the workpiece 200 conveyed to the temporary table 25 onto the chuck table 30, and a workpiece cut on the chuck table 30. A cleaning unit 28 for cleaning the workpiece 200 and a cleaning / conveying unit 29 for conveying the workpiece 200 cut on the chuck table 30 to the cleaning unit 28 are provided.

The operation of the cutting apparatus configured as described above will be described.
Prior to starting the cutting operation, the radial amplitude of the cutting blade 45 is set in accordance with the processing conditions for the workpiece 200 accommodated in the cassette 24 placed on the cassette placement table 23. The amplitude (set amplitude) set from the input means 95 is input to the control means 94 of the power supply means 7. And the amplitude detection process mentioned above is implemented using the amplitude detection means 10. FIG. In this amplitude detection step, the control means 94 of the power supply means 7 collates the radial amplitude of the cutting blade 45 determined by the amplitude determination means 16 with the set amplitude, and if there is a difference between them, the voltage adjustment means 92 And the voltage applied to the ultrasonic transducer 6 is changed. Thus, the control means 94 of the power supply means 7 sets the applied voltage when the radial amplitude of the cutting blade 45 reaches the set amplitude as the voltage of the AC power in the current cutting operation.

  If the voltage of the alternating current power supplied by the power supply means 7 is set as described above, the cutting operation is started. That is, as shown in FIG. 1, in the workpiece 200 accommodated in a predetermined position of the cassette 24 placed on the cassette placement table 23, the cassette placement table 23 moves up and down by a lifting means (not shown). Is positioned at the unloading position. Next, the unloading means 26 moves forward and backward to unload the workpiece 200 positioned at the unloading position onto the temporary placement table 25. The workpiece 200 carried out to the temporary placing table 25 is conveyed onto the chuck table 30 by the turning operation of the conveying means 27. When the workpiece 200 is placed on the chuck table 30, suction means (not shown) is operated to suck and hold the workpiece 200 on the chuck table 30. The support frame 201 that supports the workpiece 200 via the protective tape 202 is fixed by the clamp 34. The chuck table 30 holding the workpiece 200 in this way is moved to a position directly below the alignment means 21. When the chuck table 30 is positioned directly below the alignment means 21, the street formed on the workpiece 200 is detected by the alignment means 21, and the spindle unit 4 is moved and adjusted in the arrow Y direction which is the indexing direction. A precision alignment operation with the cutting blade 45 is performed.

  Thereafter, the cutting blade 45 is cut and fed by a predetermined amount in the direction indicated by the arrow Z and rotated in the predetermined direction, while the chuck table 30 holding the workpiece 200 is sucked and held in the direction indicated by the arrow X (cutting blade). The semiconductor wafer 200 held on the chuck table 30 is cut along a predetermined street by the cutting blade 45 by moving at a predetermined cutting feed rate in a direction orthogonal to the rotation axis 45. In this cutting process, AC power is applied to the ultrasonic transducer 6 by the power supply means 7. As a result, as described above, the ultrasonic transducer 6 is ultrasonically vibrated by being repeatedly displaced in the radial direction. This ultrasonic vibration is transmitted to the resonance member 44 of the cutting tool 43 via the rotary spindle 42, and the resonance member 44 ultrasonically vibrates in the radial direction. Therefore, the cutting blade 45 mounted on the resonance member 44 vibrates ultrasonically in the radial direction. Since the amplitude of the ultrasonic vibration applied to the cutting blade 45 is a value corresponding to the processing conditions, even if the wafer 200 is a difficult-to-cut material such as sapphire, it can be easily cut.

  Although the present invention has been described based on the illustrated embodiment, the present invention is not limited to the embodiment, and various modifications are possible within the scope of the gist of the present invention. For example, in the illustrated embodiment, the example in which the ultrasonic transducer 6 is disposed on the rotary spindle 4 is shown in the illustrated embodiment, but the ultrasonic transducer 6 may be directly mounted on the cutting blade 45. Good.

The perspective view of the cutting device comprised according to this invention. Sectional drawing of the spindle unit with which the cutting apparatus shown in FIG. 1 is equipped. The block block diagram of the amplitude detection means with which the cutting apparatus shown in FIG. 1 is equipped.

Explanation of symbols

2: Device housing 3: Chuck table mechanism 30: Chuck table 4: Spindle unit 41: Spindle housing 42: Rotary spindle 43: Cutting tool 44: Resonant member 45: Cutting blade 5: Electric motor 6: Ultrasonic vibrator 7: Electric power Supply means 8: Rotary transformer 81: Power reception means 82: Power supply means 91: AC power supply 92: Voltage adjustment means 93: Frequency adjustment means 94: Control means 95: Input means 10: Amplitude detection means 11: Detector 112: Light emission means 113 : Light receiving means 13: Light source 15: Photoelectric conversion means 16: Amplitude determination means 21: Alignment means 22: Display means 24: Cassette 25: Temporary placement table 26: Unloading means 27: Conveying means 28: Cleaning means 29: Cleaning and conveying means

Claims (2)

A chuck table mechanism having a chuck table for holding a workpiece, a cutting means having a cutting blade for cutting the workpiece held on the chuck table, and an ultrasonic wave for applying ultrasonic vibration to the cutting blade In a cutting apparatus comprising: a vibrator; power supply means for applying AC power to the ultrasonic vibrator; and control means for controlling the power supply means .
And it includes the amplitude detection means for detecting the amplitude of the radial the cutting blade,
The amplitude detecting means includes a light emitting means and a light receiving means which are provided on the chuck table mechanism and face each other, and a blade receiving portion which is formed between the light emitting means and the light receiving means and receives the outer periphery of the cutting blade. A photoelectric conversion means for converting the amount of light received by the light receiving means of the detector into a voltage signal, and a maximum value and a minimum value of the voltage value output from the photoelectric conversion means. An amplitude determination means for obtaining a radial amplitude,
When the radial amplitude of the cutting blade determined by the amplitude determining means deviates from the set amplitude set corresponding to the processing conditions of the workpiece, the control means A cutting apparatus , wherein the AC power to be applied is controlled to adjust the amplitude of the cutting blade to the set amplitude . The photoelectric conversion means sends a voltage corresponding to the amount of light transmitted through the light receiving means to the amplitude determination means, and the amplitude determination means has a voltage value outputted from the outer peripheral position of the cutting blade and the photoelectric conversion means. Reference data with a relationship with is entered,
Cutting device according to claim 1, characterized in that.

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