JP2020021878A - Processing device and peeling device - Google Patents

Abstract

To provide a processing device and a peeling device that can complete the specification of the resonance frequency of ultrasonic vibration means within the processing device without using an expensive frequency characteristic analyzer.SOLUTION: A processing device 10 that performs processing by vibrating processing means 28 includes resonance frequency detecting means 41 for detecting the resonance frequency of ultrasonic vibration means 30 for vibrating the processing means 28. The resonance frequency detecting means 41 includes a frequency changing unit 45 that changes the frequency of an AC voltage applied to the ultrasonic vibration means 30, a resistance value measuring unit 46 that measures a resistance value when an AC voltage is applied to the ultrasonic vibration means 30, a recording unit 47 that records the resistance value for each frequency changed by the frequency changing unit 45, and a determination unit 48 that determines the frequency of the AC voltage indicating the lowest resistance value to be the resonance frequency of the ultrasonic vibration unit 30 on the basis of the resistance value recorded by the recording unit 47.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a processing apparatus and a peeling apparatus, and more particularly to a processing apparatus and a peeling apparatus provided with a resonance frequency detecting unit of an ultrasonic vibration unit.

  2. Description of the Related Art There is known a processing apparatus or a peeling apparatus provided with a processing means or a peeling means using characteristics of an ultrasonic vibration means (for example, see Patent Documents 1 and 2).

JP-A-2006-207801 JP 2007-021701 A

  Ultrasonic vibration means are used in various industrial applications such as measurement and direct vibration of machines, but all of them have a maximum amplitude in the resonance state, and when power outside the resonance frequency is applied. Has a very small amplitude or no oscillation at all. Therefore, in the ultrasonic vibration means, tracking of the resonance frequency is indispensable to ensure safe operation even when there is a temperature change or a load change.

  However, in an apparatus provided with a processing means or a peeling means utilizing characteristics of the ultrasonic vibration means (for example, see Patent Documents 1 and 2), an expensive frequency characteristic analyzer is used to specify the resonance frequency. Needed. Further, in the above-described apparatus, it is necessary to set the above-mentioned frequency characteristic analyzer in order to specify the resonance frequency of the ultrasonic vibration means arranged inside the apparatus. Setting the characteristic analyzer is a difficult task and has a problem that it takes time.

  The present invention has been made in view of such a problem, and an object of the present invention is to perform processing capable of completing the specification of the resonance frequency of an ultrasonic vibration unit in a processing apparatus without using an expensive frequency characteristic analyzer. An apparatus and a peeling apparatus are provided.

  In order to solve the above-mentioned problems and achieve the object, a processing apparatus for processing a workpiece according to the present invention includes a processing unit for processing a workpiece, and a processing unit disposed on the processing unit and vibrating the processing unit. Ultrasonic vibration means, a power supply means for applying an AC voltage to the ultrasonic vibration means, and a resonance frequency detection means for detecting the resonance frequency of the ultrasonic vibration means, the resonance frequency detection means, A frequency changing unit that changes a frequency of an AC voltage applied to the ultrasonic vibrating unit, a resistance measuring unit that measures a resistance value when an AC voltage is applied to the ultrasonic vibrating unit, and a frequency changing unit. A recording unit that records the resistance value for each of the frequencies, based on the resistance value recorded by the recording unit, the frequency of the AC voltage indicating the lowest resistance value is the resonance frequency of the ultrasonic vibration means and A determination unit for determining At the resonance frequency detected by the frequency detection means to vibrate the processing means applies an AC voltage to the ultrasonic vibration unit, which comprises carrying out the process.

  In the processing apparatus, the resonance frequency detecting means changes an interval for changing the frequency when the resistance value is equal to or less than a predetermined value, and compares the frequency with a case where the resistance value is larger than a predetermined value. The number of resistance value measurement points may be increased. In the above-described processing apparatus, the interval at which the frequency is changed when the resistance value is equal to or less than a predetermined value may be 1/5 to 1/100 of the time when the resistance value is larger than a predetermined value. good.

  In the processing apparatus, the processing unit includes a rotary spindle for cutting a workpiece held on a chuck table, and a cutting blade attached to an end surface of the rotary spindle, and the ultrasonic vibration unit includes: Alternatively, the cutting blade may be vibrated.

  In order to solve the above-described problems and achieve the object, a peeling device for peeling a workpiece according to the present invention includes a peeling unit that peels a workpiece processed by a processing unit that processes a workpiece, Ultrasonic vibration means disposed on the peeling means for vibrating the peeling means, power supply means for applying an AC voltage to the ultrasonic vibration means, and resonance frequency detecting means for detecting the resonance frequency of the ultrasonic vibration means The resonance frequency detecting means has a frequency changing unit for changing the frequency of the AC voltage applied to the ultrasonic vibration means, and measures a resistance value when the AC voltage is applied to the ultrasonic vibration means A resistance measuring unit, a recording unit that records the resistance value for each frequency changed by the frequency changing unit, and an AC voltage indicating the lowest resistance value based on the resistance value recorded by the recording unit. The frequency of the ultrasonic vibration means Comprising a determining unit and the resonant frequency, and by vibrating the applied stripping means an AC voltage to the ultrasonic vibrating means at a resonant frequency detected by the resonant frequency detector, which comprises carrying out the peeling.

  In the peeling device, the resonance frequency detecting means changes an interval for changing the frequency when the resistance value is equal to or less than a predetermined value, and compares the frequency with a case where the resistance value is larger than a predetermined value. The number of resistance value measurement points may be increased. In the peeling apparatus, the interval for changing the frequency when the resistance value is equal to or less than a predetermined value may be 1/5 to 1/100 of the time when the resistance value is larger than a predetermined value. good.

  In the peeling apparatus, the workpiece includes an epitaxy substrate on which an optical device layer is stacked on a surface side via a buffer layer, and a transfer substrate bonded on a surface of the optical device layer via a bonding layer. A composite substrate, the processing means is a laser beam irradiation means having a laser beam oscillation means of a wavelength having a transmittance to the epitaxy substrate and absorptivity to the buffer layer, The peeling means is a horn, and the ultrasonic vibration means transfers the optical device to a transfer substrate starting from the buffer layer destroyed by irradiating the laser beam from the back side of the epitaxy substrate, and transfers the optical device to the epitaxy substrate. A horn for separating the substrate may be vibrated.

  Alternatively, in the peeling apparatus, the workpiece is single-crystal SiC, and the processing means is a laser beam irradiation means including a laser beam oscillation means having a wavelength that is transparent to the workpiece. The peeling means may be a horn, and the ultrasonic vibration means may irradiate the laser beam to vibrate a horn for peeling from a peeling layer formed on the single crystal SiC as a starting point.

  The processing apparatus and the peeling apparatus of the present invention have an effect that the resonance frequency of the ultrasonic vibration means can be completely specified in the processing apparatus without using an expensive frequency characteristic analyzer.

FIG. 1 is a perspective view illustrating an example of a processing apparatus for processing a workpiece according to the first embodiment. FIG. 2 is a perspective view of a main part of the processing apparatus shown in FIG. FIG. 3 is a block diagram showing a configuration example of the control means shown in FIG. 1 and FIG. FIG. 4 is a graph showing an example of measured data of the resistance value for each frequency of the ultrasonic vibration means shown in FIGS. 1, 2 and 3. FIG. 5 is a flowchart showing a flow of a method for detecting a resonance frequency of the processing apparatus shown in FIG. FIG. 6 is a cross-sectional view illustrating an example of the peeling device according to the second embodiment. FIG. 7 is a perspective view showing an example of a processing unit for pre-processing a workpiece to obtain a workpiece of the peeling apparatus of FIG. FIG. 8 is a cross-sectional view illustrating an example of the peeling device according to the third embodiment. FIG. 9 is a graph showing an example of measured data and a regression curve of the resistance value for each frequency of the ultrasonic vibration means according to the first modification of the first to third embodiments.

  An embodiment (embodiment) for carrying out the present invention will be described in detail with reference to the drawings. The present invention is not limited by the contents described in the following embodiments. The components described below include those that can be easily assumed by those skilled in the art and those that are substantially the same. Further, the configurations described below can be appropriately combined. In addition, various omissions, substitutions, or changes in the configuration can be made without departing from the spirit of the present invention.

[Embodiment 1]
A processing apparatus 10 according to a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a perspective view illustrating an example of a processing apparatus for processing a workpiece according to the first embodiment. FIG. 2 is a perspective view of a main part of the processing apparatus shown in FIG. FIG. 3 is a block diagram showing a configuration example of the control means shown in FIG. 1 and FIG. FIG. 4 is a graph showing an example of measured data of the resistance value for each frequency of the ultrasonic vibration means shown in FIGS. 1, 2 and 3.

  The processing apparatus 10 according to the first embodiment is an apparatus for cutting a wafer 100 which is an example of a workpiece to be processed. In the first embodiment, the workpiece is a wafer 100 such as a semiconductor wafer or an optical device wafer on which a semiconductor device or an optical device is formed. However, in the present invention, an inorganic material substrate, a ductile resin material substrate, a ceramic substrate, or a glass substrate is used. A substrate or the like may be used. As shown in FIG. 1, the wafer 100 is formed in a disk shape, and has a plurality of scheduled dividing lines 102 intersecting in a lattice pattern on a surface 101. In the wafer 100, devices 103 such as an IC (Integrated Circuit) and an LSI (Large Scale Integration) are formed in a plurality of regions defined by a plurality of planned dividing lines 102 on a surface 101. In the first embodiment, for example, the adhesive tape 108 is attached to the back surface 107 of the wafer 100, and the annular frame 109 is attached to the outer edge of the adhesive tape 108, and is supported by the annular frame 109.

  The processing apparatus 10 according to the first embodiment is an apparatus that cuts a wafer 100 along a dividing line 102. As illustrated in FIGS. 1 and 2, a processing unit 20 including a processing unit 28, The ultrasonic vibration means 30 disposed on the rotary spindle 22 for vibrating the cutting blade 21 and the rotary spindle 22, the power supply means 43 for supplying an AC voltage to the ultrasonic vibration means 30, and the respective components of the processing apparatus 10 And control means 40 for controlling.

  Further, the processing apparatus 10 aligns the chuck table 15, which is a holding unit movably provided in the X-axis direction which is the processing feed direction, with the cutting blade 21 and the wafer 100 held by the chuck table 15. An imaging unit (not shown) for imaging the surface 101 of the wafer 100 during alignment, a cleaning unit 11 for cleaning the wafer 100 after cutting, a cassette elevator 13 in which a cassette 12 for accommodating the wafer 100 is installed, and a cassette for the wafer 100 A loading / unloading unit 14 for loading / unloading from / into 12 and a display device 16 such as a monitor for displaying various information such as an image of the surface 101 of the wafer 100 captured by the imaging unit at the time of alignment and setting information regarding processing of the processing unit 20 are provided. ing.

  The processing unit 20 includes a processing means 28 and a spindle housing 23 as shown in FIG. The processing means 28 processes the wafer 100, and includes a rotary spindle 22 for cutting the wafer 100 held on the chuck table 15, and a cutting blade 21 attached to the rotary spindle 22. In the first embodiment, the processing means 28 includes the cutting blade 21 and the rotary spindle 22 for performing cutting, but the present invention is not limited to this, and other processing means may be used.

  The cutting blade 21 is attached to the end surface of the tip of a rotary spindle 22 extending along the Y-axis direction by a nut 27, and rotates around an axis parallel to the Y-axis direction with the rotation of the rotary spindle 22. Then, the wafer 100 held on the chuck table 15 is cut along the dividing line 102. The rotary spindle 22 is covered by a spindle housing 23 except for the tip where the cutting blade 21 is attached, and is rotated around the Y axis by a rotation drive mechanism (not shown) provided at the rear end. The rotary spindle 22 transmits the vibration of the ultrasonic vibration means 30 provided at the rear end to the cutting blade 21 attached to the end face of the front end.

  In the first embodiment, the ultrasonic vibration unit 30 is an electrostrictive vibrator made of a piezoelectric ceramic material such as lead zirconate titanate (PZT) or a giant magnetostrictive vibrator. It is attached to the rear end of the spindle 22. In the first embodiment, the ultrasonic vibration unit 30 generates an ultrasonic vibration of a predetermined frequency such as 50 kHz, for example, by applying an AC voltage having a frequency of approximately 50 kW to 60 kW from the power supply unit 43, and rotates the ultrasonic vibration unit 30. The spindle 22 is ultrasonically vibrated. The ultrasonic vibration is transmitted in the axial direction (Y-axis direction) of the rotating spindle 22 and travels to the cutting blade 21 mounted on the tip of the rotating spindle 22. The ultrasonic vibration means 30 ultrasonically vibrates the cutting blade 21 via the rotary spindle 22. In the ultrasonic vibration means 30, the resonance frequency at which the amplitude of the ultrasonic vibration is maximized is predetermined, and the amplitude of the ultrasonic vibration is maximized when an AC voltage having the resonance frequency is applied.

  As shown in FIG. 4, in the ultrasonic vibration unit 30, the resistance value and the amplitude of the generated ultrasonic vibration change according to the change in the frequency of the applied AC voltage. Note that the horizontal axis in FIG. 4 indicates the frequency of the AC voltage, and the vertical axis indicates the resistance value of the ultrasonic vibration unit 30. The ultrasonic vibrating means 30 has the lowest resistance value when an AC voltage having a resonance frequency is applied in a predetermined frequency range 35 as shown in resistance data measurement data 31 indicated by a white circle in FIG. That is, it is extremely small. Further, the ultrasonic vibrating means 30 has a resistance value which is equal to or less than a threshold value 34 which is a predetermined value in a range 36 near the resonance frequency, and has a resistance value larger than the threshold value 34 in a range 37 outside the resonance frequency outside the range 36. Tend to be. For this reason, the ultrasonic vibration means 30 performs ultrasonic vibration with a maximum amplitude in a resonance state formed by applying an AC voltage having a resonance frequency to any of the vibrators, and when the vibration is out of the resonance frequency, The amplitude of the sonic vibration becomes very small or no ultrasonic vibration occurs. For this reason, in order to ensure safe operation of the ultrasonic vibrating means 30 even when there is a temperature change or a load fluctuation, it is essential to track the resonance frequency in an environment during use.

  The control means 40 has a resonance frequency detecting means 41 and a power adjusting means 42 as shown in FIGS. 1, 2 and 3. The resonance frequency detection means 41 detects the resonance frequency of the ultrasonic vibration means 30, and as shown in FIG. 3, a frequency change section 45, a resistance value measurement section 46, a recording section 47, and a determination section 48. And a measurement interval changing unit 49. The power adjusting unit 42 adjusts the AC voltage applied from the power supply unit 43 to the ultrasonic vibration unit 30 to a frequency set or changed by the frequency changing unit 45 between them. , A circuit for adjusting the frequency of the AC voltage. The power adjusting unit 42 may appropriately adjust factors other than the frequency of the AC voltage, for example, the maximum value, the average value, the effective value, and the power consumption of the voltage. A circuit for adjusting the magnitude of voltage, power consumption, and the like may be incorporated.

  The frequency changing unit 45 changes the frequency of the AC voltage applied to the ultrasonic vibrating means 30 within a predetermined frequency range 35, and transmits information on the changed frequency to the power adjusting means 42. Here, the predetermined frequency range 35 changed by the frequency changing unit 45 includes the resonance frequency of the ultrasonic vibrating means 30 in an environment at the time of use, and detects two or more resonance frequencies at which the resistance value becomes a minimum. This is set in advance to a range in which only one location is detected without being performed. Specifically, in the first embodiment, the predetermined frequency range 35 is a range of about ± 10 kHz around the original resonance frequency design value of the ultrasonic vibration unit 30. For example, the design value of the resonance frequency is In the case of 40 kHz, it is in the range of 30 to 50 kHz. Note that the resonance frequency of the ultrasonic vibration unit 30 in an environment at the time of use may deviate from the original design value of the resonance frequency of the ultrasonic vibration unit 30.

  When detecting the resonance frequency, the frequency changing unit 45 changes the frequency of the AC voltage in one direction within a predetermined frequency range 35. That is, the frequency changing unit 45 changes the frequency of the AC voltage from the minimum value to the maximum value in the predetermined frequency range 35, or changes from the maximum value to the minimum value in the predetermined frequency range 35. change. After detecting the resonance frequency, the frequency changing unit 45 changes the frequency of the AC voltage to the detected resonance frequency.

  The resistance value measuring section 46 measures an electric resistance value when an AC voltage is applied to the ultrasonic vibrating means 30. In the first embodiment, the resistance value measuring section 46 is a circuit for measuring a resistance value exemplified by an ohmmeter. is there. The resistance value measuring unit 46 is electrically connected to the recording unit 47 and transmits information on the measured resistance value to the recording unit 47.

  The recording unit 47 records the resistance value measured by the resistance value measuring unit 46 sequentially for each frequency changed by the frequency changing unit 45 over the entire predetermined frequency range 35, and thereby records the ultrasonic wave. The measurement data 31 of the resistance value of the ultrasonic vibrating means 30 for the frequency of the AC voltage applied to the vibrating means 30 is acquired.

  Based on the resistance value recorded by the recording unit 47, the determination unit 48 determines the frequency of the AC voltage that indicates the lowest resistance value within the predetermined frequency range 35 that is the measurement range, The resonance frequency 33-1 of the sound wave vibration unit 30 is determined, and the determined resonance frequency 33-1 is transmitted to the frequency changing unit 45 and recorded in the recording unit 47. The determination unit 48 determines, for example, the frequency of the AC voltage having the lowest resistance value among the measurement data 31 of the resistance value shown in the graph of FIG. -1 can be determined.

  When changing the frequency of the AC voltage in one direction in the predetermined frequency range 35, the measurement interval changing unit 49 sets the AC voltage when the resistance value measured by the resistance value measuring unit 46 becomes larger than the threshold 34. Is determined to be within the range 37 outside the resonance frequency, and the frequency changing unit 45 sets the measurement interval at which the frequency is changed to the wide interval 38. When changing the frequency of the AC voltage in one direction in the predetermined frequency range 35, the measurement interval changing unit 49 sets the frequency of the AC voltage when the resistance value measured by the resistance value measuring unit 46 becomes equal to or less than the threshold 34. Is determined to be within the range 36 near the resonance frequency, and this measurement interval is changed to the narrow interval 39, so that the number of resistance value measurement points is increased as compared with the case where the resistance value is larger than the threshold value 34.

  Here, the wide interval 38 is set wider than the range 36 near the resonance frequency in order to suppress the time required for the detection of the resonance frequency, and specifically, is set at about 50 Hz or more and 100 Hz or less. In the first embodiment, the narrow interval 39 is preferably narrower than the range 36 near the resonance frequency, and is preferably set to 1/5 or more and 1/100 or less of the wide interval 38, specifically, 10 Hz or more. Set at about 1 Hz or less. The present invention is not limited to the above-described embodiment with respect to the wide interval 38 and the narrow interval 39, and the wide interval 38 is provided so that the frequency of the AC voltage when measuring the resistance value does not jump over the range 36. The frequency of the current may be set smaller than the range 36 near the resonance frequency, and preferably smaller than half of the range 36 near the resonance frequency.

  Further, the control means 40 controls each of the above-described components constituting the processing apparatus 10. That is, the control unit 40 causes the processing apparatus 10 to execute a processing operation on the wafer 100. The control means 40 applies an AC voltage of the resonance frequency 33-1 detected by the resonance frequency detection means 41 and recorded in the recording section 47 from the power supply means 43 to the ultrasonic vibration means 30 to cause the cutting blade 21 to perform ultrasonic vibration. Then, the cutting process is performed. The control means 40 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 interface device. And a computer capable of executing a computer program.

  The arithmetic processing unit of the control means 40 executes a computer program stored in the ROM on the RAM to generate a control signal for controlling the processing apparatus 10. The arithmetic processing unit of the control means 40 outputs the generated control signal to each component of the processing device 10 via the input / output interface device. The arithmetic processing unit outputs the generated control signal to the resistance value measuring unit 46 and the power adjusting unit 42 of the resonance frequency detecting unit 41 via the input / output interface device. Further, the control unit 40 is connected to the display device 16 and an input device used when the operator registers processing content information and the like. The input device includes at least one of a touch panel provided on the display device 16, a keyboard, and the like. The display device 16 displays the measurement data 31 of the resistance value for each frequency shown in FIG. 4 and a graph or an image related to the detection of the resonance frequency 33-1 such as the detected resonance frequency 33-1.

  The functions of the frequency change unit 45, the determination unit 48, and the measurement interval change unit 49 are realized by the arithmetic processing unit executing a computer program stored in the ROM on the RAM. The function of the recording unit 47 is as follows. The arithmetic processing unit executes a computer program stored in the ROM on the RAM to determine the frequency of the AC voltage applied to the ultrasonic vibrating means 30, the resistance value of the ultrasonic vibrating means 30, Is stored in the storage device.

  Next, an example of a method for detecting the resonance frequency 33-1 of the processing apparatus 10 will be described. FIG. 5 is a flowchart showing a flow of a method for detecting a resonance frequency of the processing apparatus shown in FIG. The processing apparatus 10 executes the flowchart shown in FIG. 5 when the processing apparatus 10 is shipped from a factory or when maintenance is performed. As shown in FIG. 5, the method of detecting the resonance frequency of the processing apparatus 10 includes a frequency change step ST1, a resistance value measurement step ST2, a recording step ST3, a measurement interval change step ST4, and an overall measurement confirmation step ST5. , Determination step ST6.

  The frequency changing step ST1 is a step in which the frequency changing unit 45 changes the frequency of the AC voltage applied to the ultrasonic vibrating means 30 in the predetermined frequency range 35. The frequency changing step ST1 is performed a plurality of times until the processing method includes the entire measurement confirming step ST5 until the frequency of the AC voltage is set or changed over the entire predetermined frequency range 35. . In the frequency changing step ST <b> 1, in the first embodiment, the frequency changing unit 45 sets the frequency of the AC voltage applied to the ultrasonic vibrating means 30 to a predetermined frequency range 35 when executing the first time in the processing method. Set to minimum frequency. In the frequency changing step ST1, the frequency changing unit 45 sets the frequency of the AC voltage applied to the ultrasonic vibrating means 30 to the frequency set in the previous execution when the processing method is executed for the second time or later. , The frequency is increased by the set interval 38 or the interval 39. In the frequency changing step ST1, the frequency changing unit 45 transmits information on the set or changed frequency to the power adjusting unit 42. In the frequency changing step ST <b> 1, in the first embodiment, the frequency changing unit 45 sets the frequency of the AC voltage applied to the ultrasonic vibration unit 30 to a minimum From one frequency to the maximum frequency. When the frequency of the AC voltage applied to the ultrasonic vibrating means 30 is set or changed, the process proceeds to the resistance value measuring step ST2.

  Note that the present invention is not limited to this. In the frequency changing step ST1, the frequency changing unit 45 sets the frequency of the AC voltage applied to the ultrasonic vibrating means 30 to a predetermined frequency range 35 when executing the first time. In the case of the second and subsequent executions, the frequency is set to the maximum frequency in the above, and is changed to a frequency reduced by the designated interval 38 or the interval 39 with respect to the frequency set in the previous execution, thereby obtaining a predetermined frequency. It may be changed in one direction from the maximum frequency to the minimum frequency in the frequency range 35.

  The resistance value measuring step ST2 is performed when the power adjusting unit 42 applies an AC voltage having the frequency set or changed by the frequency changing unit 45 in the frequency changing step ST1 to the ultrasonic vibrating unit 30 and applies the AC voltage. This is a step in which the resistance value measuring unit 46 measures the resistance value of the ultrasonic vibration means 30. In the resistance value measuring step ST2, first, the power adjusting unit 42 acquires information on the frequency set by the frequency changing unit 45 in the frequency changing step ST1 from the frequency changing unit 45. In the resistance value measuring step ST2, the power adjusting unit 42 adjusts the AC voltage supplied from the power supply unit 43 to the frequency acquired from the frequency changing unit 45, and applies the frequency to the ultrasonic vibration unit 30. In the resistance value measuring step ST2, the resistance value measuring section 46 measures the resistance value when an AC voltage is applied to the ultrasonic vibration means 30 thereafter.

  Note that the resistance value measuring step ST2 is executed a plurality of times, as in the frequency changing step ST1, until the resistance value is measured over the entire predetermined frequency range 35. The processing method proceeds to the recording step ST3 when the resistance value of the ultrasonic vibration means 30 when an AC voltage is applied to the ultrasonic vibration means 30 is measured.

  The recording step ST3 is a step in which the recording unit 47 records the resistance value of the ultrasonic vibration unit 30 for each frequency changed by the frequency changing unit 45. In the recording step ST3, first, the recording unit 47 acquires, from the frequency changing unit 45, information on the frequency of the AC voltage applied to the ultrasonic vibration unit 30 set or changed by the frequency changing unit 45 in the frequency changing step ST1. In the recording step ST3, next, the recording unit 47 acquires from the resistance value measuring unit 46 the information on the resistance value of the ultrasonic vibration unit 30 measured by the resistance value measuring unit 46 immediately after in the resistance value measuring step ST2. . In the recording step ST3, it is assumed that the resistance value when the recording unit 47 applies the AC voltage of the frequency acquired here to the ultrasonic vibration means 30 is the resistance value of the ultrasonic vibration means 30 acquired here. The frequency of the AC voltage and the resistance value of the ultrasonic vibration means 30 are recorded in association with each other.

  Note that the recording step ST3 is performed a plurality of times until the resistance value measured at each frequency over the entire predetermined frequency range 35 is recorded, similarly to the frequency change step ST1 and the resistance value measurement step ST2. Run across. Therefore, in the recording step ST3, a resistance value can be recorded for each frequency changed by the frequency changing unit 45. The processing method changes the measurement interval when the frequency of the AC voltage set or changed in the immediately preceding frequency change step ST1 and the resistance value of the ultrasonic vibrating means 30 measured in the immediately preceding resistance value measurement step ST2 are recorded. Proceed to step ST4.

  The measurement interval change step ST4 is a frequency change step ST1 executed next time when the measurement interval change unit 49 determines that the resistance value of the ultrasonic vibration means 30 measured in the immediately preceding resistance value measurement step ST2 becomes equal to or less than the threshold value 34. This is a step of changing the frequency changing interval from the wide interval 38 to the narrow interval 39 and increasing the number of resistance value measurement points as compared with the case where the resistance value is larger than the threshold value 34. The measurement interval change step ST4 is performed by the measurement interval change unit 49 when the resistance value of the ultrasonic vibration unit 30 measured in the immediately preceding resistance value measurement step ST2 becomes larger than the threshold value 34. This is a step of changing the frequency changing interval from the narrow interval 39 to the wide interval 38 in ST1, reducing the number of resistance value measurement points compared to the case where the resistance value is equal to or less than the threshold value 34, and returning to the original value.

  In the measurement interval changing step ST4, in detail, when the resistance value of the ultrasonic vibration means 30 measured in the immediately preceding resistance value measuring step ST2 is equal to or less than the threshold value 34, the measurement Recognizing that the resistance value of the means 30 has become equal to or less than the threshold value 34, the frequency changing step is changed from the wide interval 38 to the narrow interval 39 in the next frequency changing step ST1. Further, in the measurement interval changing step ST4, when the measurement interval changing unit 49 sets the frequency changing interval to the narrow interval 39, and when the ultrasonic vibration unit 30 measured in the immediately preceding resistance value measuring step ST2 is used. If the resistance value is larger than the threshold value 34, it is recognized that the resistance value of the ultrasonic vibration means 30 has become larger than the threshold value 34 at this stage, and the frequency changing step ST1 executed next time sets a narrow interval for changing the frequency. Change from 39 to a wide interval 38. In the measurement interval change step ST4, the measurement interval change unit 49 recognizes that it is not necessary to change the frequency change interval in the next frequency change step ST1 to be executed, and does not change the frequency change step ST1 to be executed next time. Note that the measurement interval changing unit 49 can set the interval for changing the frequency to the wide interval 38 from the beginning. Only when the above-mentioned predetermined condition is satisfied, if the frequency change interval is changed in the frequency change step ST1 to be executed next time, the process proceeds to the overall measurement confirmation step ST5.

  Note that the measurement interval changing step ST4 is performed a plurality of times until the resistance value is measured over the entire predetermined frequency range 35 in the same manner as the frequency changing step ST1, the resistance value measuring step ST2, and the recording step ST3. Run across.

  The overall measurement confirmation step ST5 is a step of confirming whether or not the resonance frequency detecting means 41 has measured the resistance value over the entire predetermined frequency range 35. In the overall measurement confirmation step ST5, specifically, it is determined whether or not the AC voltage of the frequency set or changed by the frequency changing unit 45 in the immediately preceding frequency changing step ST1 has reached the maximum frequency in the predetermined frequency range 35. Thus, it is confirmed whether or not the resistance value has been measured over the entire range 35 of the predetermined frequency. In the overall measurement confirmation step ST5, more specifically, the frequency changing unit 45 determines whether or not the frequency of the AC voltage set or changed in the immediately preceding frequency changing step ST1 is higher than the maximum frequency in the predetermined frequency range 35. Thus, it is confirmed whether or not the resistance value has been measured over the entire range 35 of the predetermined frequency.

  If the determination of No is made in the overall measurement confirmation step ST5, that is, if it is confirmed that the resonance frequency detecting means 41 does not measure the resistance value over the entire predetermined frequency range 35, the frequency change is performed. Returning to step ST1, the frequency change step ST1, the resistance value measurement step ST2, the recording step ST3, and the measurement interval change step ST4 are repeatedly executed until the resistance value is measured over the entire predetermined frequency range 35. On the other hand, in the processing method, when it was determined to be Yes in the overall measurement confirmation step ST5, that is, it was confirmed that the resonance frequency detecting means 41 measured the resistance value over the entire predetermined frequency range 35. In this case, the process proceeds to the determination step ST6. As described above, through the execution from the frequency change step ST1 to the overall measurement confirmation step ST5, the recording unit 47 obtains a series of measurement data 31 of the resistance value for each frequency of the ultrasonic vibration unit 30 as shown in FIG. Get the described graph.

  In the determination step ST6, the determination unit 48 determines, based on the resistance value recorded by the recording unit 47, the frequency of the AC voltage having the lowest resistance value, the resonance frequency of the ultrasonic vibration unit 30 under the environment at the time of the determination. 33-1. In the determination step ST6, the determination unit 48 determines, for example, the frequency of the AC voltage indicating the lowest resistance value among the measurement data 31 of the resistance values shown in the graph of FIG. It is determined to be 30 resonance frequencies 33-1. As described above, through the execution from the frequency change step ST1 to the determination step ST6, the resonance frequency detection unit 41 detects the resonance frequency 33-1 of the ultrasonic vibration unit 30 and records the resonance frequency 33-1 in the recording unit 47. When the resonance frequency 33-1 of the ultrasonic vibration means 30 in the environment at the time of the determination is detected, the flowchart illustrated in FIG. 5 ends. After that, the control means 40 of the processing apparatus 10 applies an AC voltage to the ultrasonic vibration means 30 at the resonance frequency 33-1 recorded in the recording unit 47, causes the cutting blade 21 to ultrasonically vibrate, and performs cutting. I do.

  As described above, the processing apparatus 10 according to the first embodiment includes the resonance frequency detection unit 41 that detects the resonance frequency of the ultrasonic vibration unit 30, and the resonance frequency detection unit 41 applies the resonance frequency to the ultrasonic vibration unit 30. A frequency changing unit 45 for changing the frequency of the AC voltage, a resistance measuring unit 46 for measuring a resistance value when the AC voltage is applied to the ultrasonic vibrating means 30, and a resistance for each frequency changed by the frequency changing unit 45 A recording unit 47 for recording a value, and a determining unit for determining, based on the resistance value recorded by the recording unit 47, the frequency of the AC voltage having the lowest resistance value as the resonance frequency 33-1 of the ultrasonic vibration unit 30. 48. The processing apparatus 10 applies an AC voltage to the ultrasonic vibrating means 30 at the resonance frequency 33-1 detected by the resonance frequency detecting means 41, causes the cutting blade 21 to vibrate ultrasonically via the rotary spindle 22, and performs cutting. I do. For this reason, the processing apparatus 10 according to the first embodiment can complete the specification of the resonance frequency 33-1 of the ultrasonic vibration unit 30 in the processing apparatus 10 without using an expensive frequency characteristic analyzer.

  Further, in the processing apparatus 10 according to the first embodiment, when the resonance frequency detection unit 41 determines that the resistance value of the ultrasonic vibration unit 30 is equal to or less than the threshold value 34 that is a predetermined value, the resonance frequency detection unit 41 sets the frequency change interval to a wide interval 38 Is changed to a narrow interval 39, and the number of measurement points of the resistance value is increased as compared with the case where the resistance value of the ultrasonic vibration means 30 is larger than the threshold value 34 which is a predetermined value. In addition, the processing apparatus 10 according to the first embodiment further includes the narrow interval 39 for changing the frequency when the resistance value is equal to or less than the threshold value 34 is 1/5 of the wide interval 38 when the resistance value is larger than the threshold value 34. ~ 1/100. For this reason, the processing apparatus 10 can intensively increase the number of resistance value measurement points by a range 36 near the resonance frequency considered to be a range of frequencies determined to be necessary for detecting the resonance frequency 33-1. Therefore, the measurement time for detecting the resonance frequency 33-1 can be reduced.

[Embodiment 2]
A peeling device 50 according to a second embodiment of the present invention will be described with reference to the drawings. FIG. 6 is a cross-sectional view illustrating an example of the peeling device according to the second embodiment. FIG. 7 is a perspective view illustrating an example of a processing unit that processes a workpiece to be peeled by the peeling device illustrated in FIG. 6. In FIG. 6, the same parts as those in the first embodiment are denoted by the same reference numerals, and the description is omitted.

  In Embodiment 2, as shown in FIG. 6, an optical device wafer 210 for manufacturing an optical device includes a composite substrate 300, which is a workpiece to be peeled by the peeling apparatus 50 according to Embodiment 2. And a transfer substrate 220 bonded to the optical device wafer 210. The optical device wafer 210 includes an epitaxy substrate 211 having an optical device layer 214 stacked on a surface 212 side via a buffer layer 213, a bonding layer 216 bonding the surface 215 of the optical device layer 214 and the transfer substrate 220. including. The transfer substrate 220 is bonded to the surface 215 of the optical device layer 214 via the bonding layer 216.

  In the second embodiment, the epitaxy substrate 211 is a sapphire substrate having a disk shape with a diameter of about 50 mm and a thickness of about 600 μm. In the second embodiment, the optical device layer 214 is an n-type gallium nitride semiconductor layer and a p-type gallium nitride semiconductor layer formed on the surface 212 of the epitaxy substrate 211 by an epitaxial growth method with a thickness of about 10 μm. Further, the optical device layer 214 has an optical device (not shown) formed in a plurality of regions partitioned by a plurality of planned dividing lines (not shown) intersecting in a grid pattern, similarly to the surface 101 side of the wafer 100 of the first embodiment. I have. In the second embodiment, the buffer layer 213 has a thickness formed between the surface 212 of the epitaxy substrate 211 and the n-type gallium nitride semiconductor layer of the optical device layer 214 when the optical device layer 214 is laminated on the epitaxy substrate 211. Is a GaN layer of about 1 μm.

In the composite substrate 300, a peeling layer 219 is formed on a boundary surface between the epitaxy substrate 211 and the buffer layer 213 by the processing unit 70 shown in FIG. In the second embodiment, the release layer 219 includes an N ₂ gas layer and a Ga layer. The processing unit 70 that forms the release layer 219 on the composite substrate 300 is a laser processing device in the second embodiment. As illustrated in FIG. 7, the processing unit 70 includes a holding table 72 that holds the transfer substrate 220 side of the composite substrate 300 on the holding surface 71, and a rotation drive that rotates the holding table 72 around a vertical Z-axis direction. A source 73, a laser beam irradiating means 75 for irradiating a laser beam of a predetermined wavelength from the back surface 217 side of the epitaxy substrate 211 of the composite substrate 300 held on the holding table 72, and an X for moving the holding table 72 in the X-axis direction. An axis moving unit 76, a Y-axis moving unit 77 for moving the holding table 72 in the Y-axis direction, an image pickup means 78 for picking up an image from the back surface 217 side of the composite substrate 300 held by the holding table 72, and controlling each component. And a control unit (not shown). The laser beam irradiation means 75 is a processing means for laser processing the composite substrate 300.

  The processing unit 70 images the composite substrate 300 by the imaging unit 78, performs alignment for aligning the composite substrate 300 with the laser beam irradiation unit 75, and has transparency with respect to the epitaxy substrate 211, The buffer layer 213 is oscillated with a laser beam having an absorptive wavelength by a laser beam oscillating unit provided in the laser beam irradiating unit 75 and irradiates the composite substrate 300 held on the holding table 72 from the back surface 217 side. The release layer 219 is formed by destroying the Ga compound in the buffer layer 213. The processing unit 70 then appropriately moves the position on the composite substrate 300 to which the laser beam is irradiated by the laser beam irradiation means 75 over substantially the entire surface by the rotation drive source 73, the X-axis movement unit 76, and the Y-axis movement unit 77. Thus, the release layer 219 is formed over substantially the entire boundary surface between the epitaxy substrate 211 and the buffer layer 213.

  As shown in FIG. 6, the peeling device 50 according to the second embodiment includes a peeling unit 60 including a horn 61 serving as a peeling unit, an ultrasonic vibrating unit 30 disposed on the horn 61 and ultrasonically vibrating the horn 61. , Control means 40 and power supply means 43.

  In the second embodiment, the ultrasonic vibration unit 30 ultrasonically vibrates the horn 61 instead of the rotary spindle 22 and the cutting blade 21 of the processing apparatus 10 according to the first embodiment. The ultrasonic vibration unit 30 transfers the optical device layer 214 to the transfer substrate 220 starting from the buffer layer 213, that is, the release layer 219, which has been destroyed by irradiating a laser beam from the back surface 217 side of the epitaxy substrate 211. The horn 61 for peeling off the substrate 211 is ultrasonically vibrated. The horn 61 has a front end surface 62 that contacts the back surface 217 of the composite substrate 300 to transfer the optical device layer 214 to the transfer substrate 220 and propagate ultrasonic vibration for peeling off the epitaxy substrate 211.

  In the peeling device 50 according to the second embodiment, the resonance frequency of the ultrasonic vibration unit 30 is detected and recorded in the recording unit 47, similarly to the processing device 10 according to the first embodiment. The peeling device 50 applies an AC voltage having a resonance frequency recorded in the recording unit 47 to the ultrasonic vibrating means 30 while the tip surface 62 of the horn 61 is in contact with the back surface 217 of the epitaxy substrate 211, and The optical device layer 214 is transferred to the transfer substrate 220 with the release layer 213 as a starting point, and the horn 61 is ultrasonically vibrated in order to separate the epitaxy substrate 211.

  The peeling device 50 according to the second embodiment includes a resonance frequency detection unit 41 that detects a resonance frequency of the ultrasonic vibration unit 30, and the resonance frequency detection unit 41 has the same frequency as the processing device 10 according to the first embodiment. An alternation unit 45, a resistance measurement unit 46, a recording unit 47, and a determination unit 48 are provided, and an AC voltage is applied to the ultrasonic vibration unit 30 at the resonance frequency 33-1 detected by the resonance frequency detection unit 41. The horn 61 is ultrasonically vibrated. For this reason, similarly to the processing apparatus 10 according to the first embodiment, the peeling device 50 according to the second embodiment uses the resonance frequency of the ultrasonic vibration unit 30 in the peeling device 50 without using an expensive frequency characteristic analyzer. The specification of 33-1 can be completed.

  Further, similarly to the processing apparatus 10 according to the first embodiment, the peeling device 50 according to the second embodiment changes the frequency when the resonance frequency detecting unit 41 has a resistance value equal to or lower than a threshold value 34 which is a predetermined value. The interval to be changed is changed from the interval 38 to the interval 39. Further, in the peeling device 50 according to the second embodiment, similarly to the processing device 10 according to the first embodiment, the interval 39 for changing the frequency when the resistance value becomes equal to or less than the predetermined value is 1/1/3 of the interval 38. It is 5/1/100. For this reason, the peeling device 50 can intensively increase the number of measurement points of the resistance value only in the range 36 near the resonance frequency considered to be the range of the frequency determined to be necessary for detecting the resonance frequency 33-1. Therefore, the measurement time for detecting the resonance frequency 33-1 can be reduced.

[Embodiment 3]
A peeling device 80 according to Embodiment 3 of the present invention will be described with reference to the drawings. FIG. 8 is a cross-sectional view illustrating an example of the peeling device according to the third embodiment. In FIG. 8, the same portions as those in the first and second embodiments are denoted by the same reference numerals, and description thereof will be omitted.

  Single crystal SiC400, which is an example of a workpiece to be peeled by the peeling device 80 according to the third embodiment, is an ingot made of SiC (silicon carbide), the upper surface 402 is polished, and a modified portion and a modified portion are provided inside. And a crack isotropically formed on the c-plane. The release layer 401 is formed by the same laser processing apparatus as the processing unit 70 described in the second embodiment. The modified part means the area where the density, refractive index, mechanical strength and other physical properties are different from those of the surrounding area, melt processing area, crack area, dielectric breakdown area, refractive index change Examples include a region, a region in which these regions are mixed, and the like.

  The processing unit 70 places a laser beam having a wavelength that is transmissive to the single crystal SiC 400 from the laser beam irradiation means 75 as a processing means, with its focal point positioned at a predetermined depth from the upper surface 402 of the single crystal SiC 400. Irradiation is performed on the single crystal SiC 400 to form a modified portion, that is, a release layer 401. The workpiece to be peeled by the peeling device 80 according to the third embodiment is not limited to the single crystal SiC 400, and may be a single crystal ingot having another peel layer formed thereon.

  As shown in FIG. 8, the peeling device 80 according to the third embodiment includes a peeling unit 90 including a horn 91 as a peeling unit, an ultrasonic vibrating unit 30 disposed on the horn 91 and ultrasonically vibrating the horn 91. , Control means 40 and power supply means 43. The peeling unit 90 includes a horn 91, a water supply unit 92 for forming a medium layer 93 of water for transmitting the ultrasonic vibration of the horn 91 to the upper surface 402 of the single crystal SiC 400, and a single crystal SiC 400 with the upper surface 402 side facing upward. And a holding table 94 having a holding surface 95 for holding the holding table 95.

  The ultrasonic vibration unit 30 irradiates a laser beam shown in FIG. 8 instead of the rotary spindle 22 and the cutting blade 21 of the processing apparatus 10 according to the first embodiment and the horn 61 of the peeling apparatus 50 according to the second embodiment. The horn 91 for peeling from the peeling layer 401 formed on the single-crystal SiC 400 is ultrasonically vibrated. The horn 91 comes into contact with the water medium layer 93 formed on the upper surface 402 side of the single crystal SiC 400, so that ultrasonic vibration for separating the single crystal SiC 400 is applied to the single crystal SiC 400 via the water medium layer 93. Propagate.

  The peeling device 80 according to the third embodiment detects the resonance frequency of the ultrasonic vibration unit 30 and records the resonance frequency in the recording unit 47, similarly to the processing device 10 according to the first embodiment and the peeling device 50 according to the second embodiment. You. The peeling device 80 applies the AC voltage of the resonance frequency recorded in the recording unit 47 to the ultrasonic vibrating means 30 while the horn 91 is in contact with the water medium layer 93 formed on the upper surface 402 of the single crystal SiC 400. With the application, the horn 91 is ultrasonically vibrated in order to separate the upper surface 402 from the single crystal SiC 400 with the separation layer 401 as a starting point.

  The peeling device 80 according to the third embodiment includes a resonance frequency detection unit 41 that detects a resonance frequency of the ultrasonic vibration unit 30, and the resonance frequency detection unit 41 changes the frequency as in the first and second embodiments. Unit 45, a resistance measurement unit 46, a recording unit 47, and a determination unit 48, and applies an AC voltage to the ultrasonic vibration unit 30 at the resonance frequency 33-1 detected by the resonance frequency detection unit 41, The horn 91 is ultrasonically vibrated. For this reason, the peeling device 80 according to the third embodiment can perform the resonance frequency 33 of the ultrasonic vibration unit 30 in the peeling device 80 without using an expensive frequency characteristic analyzer, as in the first and second embodiments. -1 can be completed.

  Further, in the peeling device 80 according to the third embodiment, similarly to the first and second embodiments, the resonance frequency detecting unit 41 changes the frequency when the resistance value becomes equal to or less than the threshold value 34 which is a predetermined value. The interval is changed from the interval 38 to the interval 39. Further, in the peeling device 80 according to the third embodiment, similarly to the first and second embodiments, the interval 39 for changing the frequency when the resistance value becomes equal to or less than the predetermined value is １ ／ of the interval 38. ~ 1/100. For this reason, the peeling device 80 can shorten the measurement time for detecting the resonance frequency 33-1 as in the first and second embodiments.

[Modification 1]
A first modification of the first to third embodiments of the present invention will be described with reference to the drawings. FIG. 9 is a graph showing an example of measured data and a regression curve of the resistance value for each frequency of the ultrasonic vibration means according to the first modification of the first to third embodiments. In FIG. 9, the same portions as those in the first, second, and third embodiments are denoted by the same reference numerals, and description thereof will be omitted.

  The first modification of the present invention is the same as the first, second, and third embodiments except that the processing function of the determination unit 48 of the resonance frequency detection unit 41 included in the control unit 40 is changed.

  The determining unit 48 according to the first modification calculates a regression curve 32 regressed on the measurement data 31 based on the resistance value measurement data 31 shown in the graph of FIG. The frequency of the AC voltage indicating the resistance value is determined as the resonance frequency 33-2 of the ultrasonic vibration means 30 under the environment at the time of the determination. In the first modification, the processing apparatus 10 and the peeling apparatuses 50 and 80 apply an AC voltage having a resonance frequency of 33-2 to the ultrasonic vibration unit 30 in the processing operation on the wafer 100, the composite substrate 300, and the single crystal SiC400. .

  In the first modification, as described above, the determination unit 48 further calculates the regression curve 32 based on the measured resistance value data 31, and determines the frequency of the AC voltage showing the lowest resistance value in the regression curve 32. Is determined as the resonance frequency 33-2 of the ultrasonic vibration means 30 under the environment at the time of the determination, so that the processing apparatus 10 according to the first embodiment, the peeling apparatus 50 according to the second embodiment, and the peeling apparatus according to the third embodiment At 80, the resonance frequency 33-2 of the ultrasonic vibration means 30 can be specified with high accuracy.

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

DESCRIPTION OF SYMBOLS 10 Processing apparatus 28 Processing means 30 Ultrasonic vibration means 33-1 and 33-2 Resonance frequency 34 Threshold value (predetermined value)
38, 39 interval 41 resonance frequency detecting means 42 power adjusting means 43 power supplying means 45 frequency changing unit 46 resistance value measuring unit 47 recording unit 48 determining unit 50, 80 peeling device 60, 90 peeling unit 61, 91 horn 75 laser beam irradiation Means (processing means)
100 wafer (workpiece)
211 Epitaxy substrate 212 Surface 213 Buffer layer 214 Optical device layer 215 Surface 216 Bonding layer 220 Transfer substrate 300 Composite substrate 400 Single crystal SiC (workpiece)
401 release layer

Claims (9)

Processing means for processing the workpiece;
Ultrasonic vibration means disposed on the processing means and vibrating the processing means,
Power supply means for applying an AC voltage to the ultrasonic vibration means,
Having a resonance frequency detection means for detecting a resonance frequency of the ultrasonic vibration means,
The resonance frequency detecting means includes:
A frequency changing unit that changes the frequency of the AC voltage applied to the ultrasonic vibration unit,
A resistance value measurement unit that measures a resistance value when an AC voltage is applied to the ultrasonic vibration unit,
A recording unit that records the resistance value for each frequency changed by the frequency changing unit,
Based on the resistance value recorded by the recording unit, a determination unit that determines the frequency of the AC voltage indicating the lowest resistance value as the resonance frequency of the ultrasonic vibration unit,
A processing apparatus for processing a workpiece, wherein an AC voltage is applied to the ultrasonic vibration means at the resonance frequency detected by the resonance frequency detection means to cause the processing means to vibrate and perform processing.   The resonance frequency detecting means changes the frequency change interval when the resistance value is equal to or less than a predetermined value, and compares the resistance value with a case where the resistance value is larger than the predetermined value, and measures the number of measurement points of the resistance value. The processing apparatus according to claim 1, wherein the number is increased.   The interval for changing the frequency when the resistance value is equal to or less than a predetermined value is 1/5 to 1/100 of the time when the resistance value is larger than a predetermined value. The processing device as described. The processing means,
A rotary spindle for cutting the workpiece held on the chuck table,
A cutting blade mounted on the end face of the rotating spindle;
The processing apparatus according to any one of claims 1 to 3, wherein the ultrasonic vibration unit vibrates the cutting blade. Peeling means for peeling the workpiece processed by the processing means for processing the workpiece,
Ultrasonic vibration means disposed on the peeling means and vibrating the peeling means,
Power supply means for applying an AC voltage to the ultrasonic vibration means,
Having a resonance frequency detection means for detecting a resonance frequency of the ultrasonic vibration means,
The resonance frequency detecting means includes:
A frequency changing unit that changes the frequency of the AC voltage applied to the ultrasonic vibration unit,
A resistance value measurement unit that measures a resistance value when an AC voltage is applied to the ultrasonic vibration unit,
A recording unit that records the resistance value for each frequency changed by the frequency changing unit,
Based on the resistance value recorded by the recording unit, a determination unit that determines the frequency of the AC voltage indicating the lowest resistance value as the resonance frequency of the ultrasonic vibration unit,
An exfoliation device for exfoliating a workpiece, wherein an alternating voltage is applied to the ultrasonic vibrating means at the resonance frequency detected by the resonance frequency detecting means to vibrate the exfoliating means to perform exfoliation.   The resonance frequency detecting means changes the frequency change interval when the resistance value is equal to or less than a predetermined value, and compares the resistance value with a case where the resistance value is larger than the predetermined value, and measures the number of measurement points of the resistance value. The peeling device according to claim 5, wherein the number is increased.   The interval for changing the frequency when the resistance value becomes equal to or less than a predetermined value is 1/5 to 1/100 of the time when the resistance value is larger than a predetermined value. The peeling device according to claim 1. The workpiece is a composite substrate including an epitaxy substrate having an optical device layer laminated on a surface side via a buffer layer, and a transfer substrate joined to the surface of the optical device layer via a joining layer. ,
The processing means is a laser beam irradiating means having a laser beam oscillating means having a wavelength having a transmittance to the epitaxy substrate and having an absorptivity to the buffer layer,
The peeling means is a horn,
The ultrasonic vibration means transfers the optical device to the transfer substrate starting from the buffer layer destroyed by irradiating the laser beam from the back side of the epitaxy substrate, and provides a horn for peeling the epitaxy substrate. The peeling device according to any one of claims 5 to 7, wherein the device is vibrated. The workpiece is single crystal SiC,
The processing means is a laser beam irradiation means provided with a laser beam oscillation means of a wavelength having transparency to the workpiece,
The peeling means is a horn,
The ultrasonic vibration means vibrates a horn for peeling from a peeling layer formed on the single crystal SiC by irradiating the laser beam with the laser beam, as claimed in any one of claims 5 to 7. The peeling apparatus according to claim 1.

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