KR20240018366A - Laser machining apparatus - Google Patents

Abstract

The purpose of the present invention is to provide a laser processing device that can determine the state of laser light without reducing productivity.
The laser processing device includes a laser oscillator 30 that generates laser light 21, a condensing lens 32 that focuses the laser light 21 generated by the laser oscillator 30, and the laser oscillator 30. a separation member 33 for separating the laser light 21 generated by the inspection laser light 22 and a processing laser light 22 for concentrating the laser light 22 on the workpiece 100; From the light receiving unit 40 that receives the inspection laser light 22 separated by the light receiving unit 40, information about the intensity of the laser light 22, and the laser light 22 ) and a control unit 54 that outputs the information acquired by the detection unit 50.

Description

Laser processing device {LASER MACHINING APPARATUS}

The present invention relates to a laser processing device.

In order to divide a plate-shaped material such as a semiconductor wafer into chips, a laser light having a wavelength that is transparent to the plate-shaped material is concentrated and irradiated into the inside of the plate-shaped material to form a modified layer, and the modified layer is divided as a starting point. A method of splitting a plate-shaped material by irradiating a laser beam of an absorptive wavelength to ablate the plate-shaped material is known (see Patent Documents 1 and 2). In this processing method, it is very important to determine the state of the laser light of the laser processing device in order to stabilize processing quality.

[Patent Document 1] Japanese Patent No. 3408805 [Patent Document 2] Japanese Patent Publication No. 10-305420

However, conventionally, power meters that measure the intensity of laser light need to be installed to block the laser light. Therefore, there was a problem that processing had to be stopped for measurement and productivity was reduced. In addition, in order to observe the pulse waveform or pulse loss of the laser light, it is necessary to install a photodiode in a position where scattered light can be received, connect it to an oscilloscope, and check it with the naked eye, which not only reduces productivity as in the case of intensity measurement. , it was a cumbersome task.

The present invention was made in view of these problems, and its purpose is to provide a laser processing device that can determine the state of laser light without reducing productivity.

In order to solve the above-described problems and achieve the object, the laser processing device of the present invention includes a laser oscillator that generates laser light, a condensing lens that focuses the laser light generated by the laser oscillator, and the laser oscillator. A separation member that separates the laser light generated by the inspection laser light and the processing laser light for concentrating the laser light on the workpiece, a light receiving unit that receives the inspection laser light separated by the separation member, and the light receiving unit. It is characterized by comprising a detection unit that acquires information about the intensity of the laser light and information about the pulse waveform of the laser light from the received laser light, and a control section that outputs the information acquired by the detection unit.

In addition, the laser processing device of the present invention further includes a branching mirror for branching the inspection laser beam separated by the separation member, and the light receiving unit receives one laser beam branched by the branching mirror to receive the laser beam for inspection. You may have a thermal sensor that measures the average output of the laser light, and a photodetector that receives the other laser light branched by the branching mirror and acquires information about the pulse waveform of the laser light.

Furthermore, in the laser processing device of the present invention, the thermal sensor may be arranged to receive the laser light reflected by the branching mirror, and the photodetector may be arranged to receive the laser light that has passed through the branching mirror.

Additionally, in the laser processing device of the present invention, an ND filter may be disposed between the branch mirror and the photodetector.

In addition, in the laser processing device of the present invention, the information about the pulse waveform of the laser light acquired by the detection unit includes information about the presence or absence of pulse omission, and the control unit determines the pulse waveform of the laser light based on the average output of the laser light. Therefore, the threshold for detecting missing pulses may be automatically set.

The present invention can determine the state of laser light without reducing productivity.

1 is a perspective view showing a configuration example of a laser processing device according to an embodiment.
FIG. 2 is a schematic diagram showing a schematic configuration example of the laser light irradiation unit shown in FIG. 1.
Figure 3 is a schematic diagram showing another schematic configuration example of a laser light irradiation unit.
Figure 4 is a schematic diagram showing another schematic configuration example of a light receiving unit.
FIG. 5 is a graph showing an example of the trend of the average output of laser light received by the thermal sensor shown in FIG. 4.
FIG. 6 is a graph showing an example of the change in output of laser light received by the photo detector shown in FIG. 4.

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

[Embodiment]

First, the overall configuration of the laser processing device 1 according to an embodiment of the present invention will be described based on the drawings. Fig. 1 is a perspective view showing a configuration example of a laser processing device 1 according to an embodiment. In the following description, the X-axis direction is one direction in the horizontal plane. The Y-axis direction is a direction perpendicular to the X-axis direction in the horizontal plane. The Z-axis direction is a direction perpendicular to the X-axis direction and the Y-axis direction. In the laser processing apparatus 1 of the embodiment, the processing transfer direction is the X-axis direction, the indexing transfer direction is the Y-axis direction, and the converging point position adjustment direction is the Z-axis direction.

As shown in FIG. 1, the laser processing device 1 includes a holding table 10, a laser light irradiation unit 20, a moving unit 60, an imaging unit 70, and a display unit 80. ) is provided. The laser processing device 1 according to the embodiment is an apparatus that processes a workpiece 100 by irradiating a laser beam 21 to the workpiece 100 that is a processing target. Processing of the workpiece 100 by the laser processing device 1 includes, for example, modified layer forming processing to form a modified layer inside the workpiece 100 by stealth dicing, and forming a modified layer on the surface of the workpiece 100. This includes groove machining to form a groove, or cutting machining to cut the workpiece 100 along a line to be divided.

The workpiece 100 is, for example, a disk-shaped material made of silicon (Si), sapphire (Al ₂ O ₃ ), gallium arsenide (GaAs), silicon carbide (SiC), or lithium tantalate (LiTaO ₃ ) as a substrate. These are wafers such as semiconductor device wafers and optical device wafers. In addition, the workpiece 100 is disk-shaped in the embodiment, but may not be disk-shaped in the present invention. For the workpiece 100, for example, a circular frame 110 is adhered, and a tape 111 with a larger diameter than the outer diameter of the workpiece 100 is bonded to the back side of the workpiece 100, It is transported and processed while supported within the opening of the frame 110.

The holding table 10 holds the workpiece 100 on the holding surface 11 . The holding surface 11 has a disk shape made of porous ceramic or the like. In the embodiment, the holding surface 11 is a plane parallel to the horizontal direction. The holding surface 11 is connected to a vacuum suction source through a vacuum suction path, for example. The holding table 10 suction-holds the workpiece 100 placed on the holding surface 11. Around the holding table 10, a plurality of clamp parts 12 for clamping the annular frame 110 supporting the workpiece 100 are arranged.

The holding table 10 is rotated around an axis parallel to the Z-axis direction by the rotation unit 13. The rotation unit 13 is supported on an X-axis direction moving plate 14. The rotation unit 13 and the holding table 10 are moved in the X-axis direction via the X-axis direction movement plate 14 by an X-axis direction movement unit 61, which will be described later. The rotation unit 13 and the holding table 10 are connected to the Y-axis direction movement unit (described later) through the X-axis direction movement plate 14, the 62) is moved in the Y-axis direction.

The laser beam irradiation unit 20 is a unit that irradiates the laser beam 21 to the workpiece 100 held on the holding surface 11 of the holding table 10. Among the laser light irradiation units 20, at least the condenser lens 32 (see FIG. 2) is a Z-axis direction moving unit described later installed on the pillar 3 raised from the device main body 2 of the laser processing device 1. Supported in (63). A specific configuration example of the laser light irradiation unit 20 will be described in detail later.

The moving unit 60 is a unit that moves the condensing point of the laser light 21 relative to the workpiece 100 held on the holding table 10. The movement unit 60 includes an X-axis direction movement unit 61, a Y-axis direction movement unit 62, and a Z-axis direction movement unit 63.

The X-axis direction movement unit 61 is a unit that relatively moves the holding table 10 and the condensing point of the laser beam irradiation unit 20 in the X-axis direction, which is the processing transfer direction. In the embodiment, the X-axis direction movement unit 61 moves the holding table 10 in the X-axis direction. In the embodiment, the X-axis direction movement unit 61 is installed on the device main body 2 of the laser processing device 1. The X-axis direction movement unit 61 supports the X-axis direction movement plate 14 so that it is movable in the X-axis direction.

The Y-axis direction movement unit 62 is a unit that relatively moves the holding table 10 and the condensing point of the laser beam irradiation unit 20 in the Y-axis direction, which is the indexing transfer direction. In the embodiment, the Y-axis direction movement unit 62 moves the holding table 10 in the Y-axis direction. In the embodiment, the Y-axis direction movement unit 62 is installed on the device main body 2 of the laser processing device 1. The Y-axis direction movement unit 62 supports the Y-axis direction movement plate 15 movably in the Y-axis direction.

The Z-axis direction movement unit 63 is a unit that relatively moves the holding table 10 and the converging point of the laser beam irradiation unit 20 in the Z-axis direction, which is the condensing point position adjustment direction. In the embodiment, the Z-axis direction movement unit 63 moves at least the converging lens 32 of the laser beam irradiation unit 20 in the Z-axis direction. In the embodiment, the Z-axis direction movement unit 63 is installed on a pillar 3 raised from the device main body 2 of the laser processing device 1. The Z-axis direction movement unit 63 supports at least the converging lens 32 of the laser beam irradiation unit 20 so that it can move in the Z-axis direction.

In the embodiment, the Includes rails. The ball screw is installed to be rotatable about the axis. The pulse motor rotates the ball screw around its axis. The guide rail of the X-axis direction movement unit 61 supports the X-axis direction movement plate 14 movably in the X-axis direction. The guide rail of the X-axis direction movement unit 61 is fixed and installed to the Y-axis direction movement plate 15. The guide rail of the Y-axis direction movement unit 62 supports the Y-axis direction movement plate 15 movably in the Y-axis direction. The guide rail of the Y-axis direction movement unit 62 is fixed and installed on the device main body 2. The guide rail of the Z-axis direction movement unit 63 supports at least the converging lens 32 of the laser beam irradiation unit 20 so that it can move in the Z-axis direction. The guide rail of the Z-axis direction movement unit 63 is fixed to the pillar 3 and installed.

The imaging unit 70 captures an image of the workpiece 100 held on the holding table 10 . The imaging unit 70 includes a CCD (Charge Coupled Device) camera or an infrared camera. The imaging unit 70 is fixed, for example, adjacent to the converging lens 32 (see FIG. 2) of the laser beam irradiation unit 20. The imaging unit 70 captures an image of the workpiece 100, obtains an image for alignment of the workpiece 100 and the laser beam irradiation unit 20, and outputs the obtained image.

The display unit 80 is a display unit comprised of a liquid crystal display device or the like. The display unit 80 displays, for example, a setting screen for processing conditions, the state of the workpiece 100 imaged by the imaging unit 70, the state of the processing operation, etc., on the display screen. When the display surface of the display unit 80 includes a touch panel, the display unit 80 may include an input unit. The input unit can accept various operations such as registering processing content information by the operator. The input unit may be an external input device such as a keyboard. In the display unit 80, information and images displayed on the display screen are switched by operations from an input unit or the like.

Next, the specific configuration of the laser light irradiation unit 20 will be described. FIG. 2 is a schematic diagram showing a schematic configuration example of the laser light irradiation unit 20 shown in FIG. 1. As shown in FIG. 2, the laser light irradiation unit 20 includes a laser oscillator 30 and a condensing lens 32.

The laser oscillator 30 generates and emits laser light 21 having a predetermined wavelength for processing the workpiece 100. The laser light 21 irradiated by the laser light irradiation unit 20 is laser light with a wavelength that transmits or absorbs the workpiece 100. The laser oscillator 30 has a laser oscillator 31 containing a laser medium that oscillates and amplifies the laser light 21. In addition, the laser oscillator 30 of the embodiment is provided with a separation member 33, a light receiving unit 40, a detection unit 50, and a control unit 54 inside the housing.

The separation member 33 is installed on the optical path of the laser beam 21 between the laser oscillation unit 31 and the converging lens 32. The separation member 33 separates the laser light 21 generated in the laser oscillation unit 31 into a laser light 22 for inspection and a laser light 23 for processing.

The separation member 33 of the embodiment includes, for example, glass and transmits more than 99% of the laser light 21 and reflects less than 1 percent. That is, the separation member 33 of the embodiment guides the reflected laser light 21 as the laser light 22 for inspection to the light receiving unit 40, and converts the transmitted laser light 21 into the laser light 23 for processing. It is guided to the condensing lens 32. Additionally, the separation member 33 may include a reflecting mirror. In this case, the reflected laser light 21 is guided to the converging lens 32 as the laser light 23 for processing, and the transmitted laser light 21 is guided to the converging lens 32. ) may be arranged to be guided to the light receiving unit 40 as the inspection laser light 22.

The light receiving unit 40 receives the inspection laser light 22 separated by the separation member 33. The light receiving unit 40 of the embodiment includes a photodetector that detects light by converting an optical signal into an electric signal. Additionally, a filter that attenuates the amount of light may be disposed in front of the light receiving unit 40. The filter includes, for example, an ND (Neutral Density) filter that lowers the amount of light by a certain amount and transmits it without selecting the wavelength in a predetermined wavelength range. The light receiving unit 40 outputs an electrical signal corresponding to the received light to the detection unit 50.

The detection unit 50 is a unit that acquires information on the inspection laser light 22 received by the light receiving unit 40. The detection unit 50 includes a signal amplification unit 51, a pulse waveform information acquisition unit 52, and a light intensity information acquisition unit 53. The signal amplifier 51 amplifies the electric signal acquired from the light receiving unit 40 and outputs it to the pulse waveform information acquisition unit 52 and the light intensity information acquisition unit 53.

The pulse waveform information acquisition unit 52 acquires an electrical signal of light intensity corresponding to information about the pulse waveform of the laser light 22. The light intensity information acquisition unit 53 acquires an electrical signal of light intensity corresponding to information about the intensity of the laser light 22. Additionally, the pulse waveform information acquisition unit 52 and the light intensity information acquisition unit 53 acquire each information as an analog signal. The pulse waveform information acquisition unit 52 and the light intensity information acquisition unit 53 output analog signals corresponding to each acquired information to the control unit 54.

The control unit 54 is a computer that includes an arithmetic processing device as a calculation means, a memory device as a storage means, and an input/output interface device as a communication means. The arithmetic processing unit includes, for example, a microprocessor such as a CPU (Central Processing Unit). The storage device has memory such as HDD (Hard Disk Drive), ROM (Read Only Memory), or RAM (Random Access Memory). The arithmetic processing unit performs various calculations based on a predetermined program stored in a memory device. The arithmetic processing device outputs various control signals to each of the above-described components through an input/output interface device according to the arithmetic results.

The control unit 54 performs AD conversion on the analog signals acquired from the pulse waveform information acquisition unit 52 and the light intensity information acquisition unit 53. Additionally, the control unit 54 converts the AD value of the light intensity into a power value. Accordingly, the control unit 54 obtains time transition information of the peak output from the electrical signal of the light intensity corresponding to the information about the pulse waveform of the laser light 22 acquired by the pulse waveform information acquisition unit 52. Additionally, the control unit 54 obtains time transition information of the average output from the electrical signal of the light intensity corresponding to the information on the intensity of the laser beam 22 acquired by the light intensity information acquisition unit 53.

The control unit 54 acquires the time transition of the average output of the laser beam 22 based on the information regarding the intensity of the inspection laser beam 22 acquired by the detection unit 50. Since the inspection laser light 22 and the processing laser light 23 are separated at a predetermined ratio in the separation member 33, the processing laser light 23 is determined by the time change of the average output of the laser light 22. ) It is possible to estimate the time trend of the average output. That is, based on the time transition of the average output of the processing laser light 23, device abnormalities such as an unexpected decrease in the intensity of the laser light 23, for example, can be detected.

Additionally, the control unit 54 acquires the time transition of the peak output of the laser light 22 based on information about the pulse waveform of the inspection laser light 22 acquired by the detection unit 50. Since the inspection laser light 22 and the processing laser light 23 are separated at a predetermined ratio in the separation member 33, the processing laser light 23 is determined by the time transition of the peak output of the laser light 22. ) It is possible to estimate the time trend of the peak output. That is, the control unit 54 can detect device abnormalities such as missing pulses of the laser light 23, for example, based on the time transition of the peak output of the processing laser light 23.

Here, the information about the pulse waveform of the laser light 22 acquired by the pulse waveform information acquisition unit 52 of the detection unit 50 may include information about the presence or absence of pulse omission. Detection of pulse omission is performed by determining whether the peak output for each pulse falls below a predetermined threshold. The control unit 54 of the embodiment automatically sets a threshold for detecting pulse omission based on the time transition of the average output of the laser light 22. Accordingly, it is possible to respond even when the processing conditions are changed during irradiation of the laser light 21 and the appropriate threshold value changes.

The condenser lens 32 condenses the laser light 21 emitted from the laser oscillator 30 onto the workpiece 100 held on the holding surface 11 of the holding table 10, thereby forming the workpiece 100. Investigate it. The condenser lens 32 directs the processing laser light 23, which has passed through the separation member 33, out of the laser light 21 emitted from the laser oscillation unit 31 and incident on the separation member 33, to the workpiece 100. ) is focused on.

In the laser light irradiation unit 20 of the embodiment shown in FIG. 2, the light receiving unit 40 and the detection unit 50 are disposed inside the laser oscillator 30, but the present invention is not limited to this form. Fig. 3 is a schematic diagram showing another schematic configuration example of the laser light irradiation unit 20-1. As shown in FIG. 3, the laser light irradiation unit 20-1 is provided with a laser oscillator 30-1 instead of the laser oscillator 30, compared to the laser light irradiation unit 20 of the embodiment. It is different in that respect.

The laser oscillator 30-1 does not have a separation member 33, a light receiving unit 40, a detection unit 50, and a control unit 54 inside. That is, the laser light irradiation unit 20-1 includes a separation member 33, a light receiving unit 40, a detection unit 50, and a control unit 54 outside the laser oscillator 30-1. The separation member 33 separates the laser light 21 emitted from the laser oscillator 30-1 into the laser light 22 for inspection and the laser light 23 for processing. As for other structural parts, since they are the same as the structural parts of the laser beam irradiation unit 20 shown in FIG. 2, description is omitted.

The light receiving unit 40 of the embodiment includes a photo detector, but in the present invention, it may further include a thermal sensor. Figure 4 is a schematic diagram showing another schematic configuration example of the light receiving unit 40-1. The light receiving unit 40-1 includes a thermal sensor 42 and a photodetector 43 that respectively receive the laser lights 24 and 25 branched by the branching mirror 41.

The branch mirror 41 branches the inspection laser light 22 separated by the separation member 33. The branching mirror 41 guides one branched laser light 22 as the laser light 24 to the thermal sensor 42, and guides the other branched laser light 22 as the laser light 25 to a photo detector ( 43). The branching mirror 41 is a reflective mirror that reflects about 99% of the laser light 22, for example. The branch mirror 41 reflects approximately 99% of the laser light 22 and guides it to the thermal sensor 42 as the laser light 24, and transmits the remaining 1% to guide it to the photo detector 43.

The thermal sensor 42 receives one laser beam 24 branched by the branching mirror 41 and measures the average output of the laser beam 24. The thermal sensor 42 of the embodiment receives the laser light 24 reflected by the diverging mirror 41.

The photo detector 43 receives the other laser beam 25 branched by the branching mirror 41 and acquires information about the pulse waveform of the laser beam 25. The photodetector 43 of the embodiment receives the laser light 25 that passed through the branching mirror 41.

As shown in FIG. 4, a condensing lens 44 and a wavelength selection filter 45 are disposed at the front end of the branching mirror 41. Additionally, an ND filter 46 is disposed between the branch mirror 41 and the photo detector 43.

The condenser lens 44 condenses the inspection laser light 22 separated by the separation member 33 toward the light-receiving surface of the photo detector 43. The laser light 22 that has passed through the converging lens 44 passes through the wavelength selection filter 45, the branching mirror 41, and the ND filter 46, and is incident on the photo detector 43.

The wavelength selection filter 45 is disposed on the optical path of the inspection laser light 22 between the converging lens 44 and the diverging mirror 41. The wavelength selection filter 45 is a filter that transmits only a predetermined wavelength among the inspection laser light 22. The wavelength selection filter 45 is, for example, one of a band-pass filter, a dichroic filter, a long-pass filter, and a short-pass filter, or a combination of these filters. A band pass filter is a filter that randomly selects and transmits a specific wavelength. A dichroic filter is a filter that reflects light in a specific wavelength range and transmits light in the remaining wavelength range. A long pass filter is a filter that transmits light with a wavelength longer than a predetermined wavelength. A short pass filter is a filter that transmits light with a wavelength shorter than a predetermined wavelength. The wavelength selection filter 45 of the embodiment transmits only the wavelengths that can be measured by the thermal sensor 42 and the photo detector 43.

The ND filter 46 lowers the amount of light of the laser light 25 branched by the branching mirror 41 by a certain amount and transmits it. Accordingly, the amount of laser light 25 incident on the photo detector 43 can be lowered.

Here, in the laser processing device (1) provided with a light receiving unit (40) having both a thermal sensor (42) and a photo detector (43), a method of automatically setting a threshold value (93) for detecting missing pulses Explain. FIG. 5 is a graph showing an example of the trend of the average output of the laser light 24 received by the thermal sensor 42 shown in FIG. 4. FIG. 6 is a graph showing an example of the output of the laser light 25 received by the photo detector 43 shown in FIG. 4. In the example shown in FIGS. 5 and 6 , the laser processing conditions are changed from the first processing conditions 91 to the second processing conditions 92 in the middle.

The control unit 54 estimates the transition of the average output of the laser light 23 for processing as shown in FIG. 5 based on the average output of the laser light 24 acquired by the thermal sensor 42. As shown in FIG. 5, while laser processing is performed under the first processing conditions 91, the average output of the laser light 23 is approximately constant. Additionally, while laser processing is performed under the second processing condition 92, the average output of the laser light 23 is approximately constant. Additionally, by transitioning from the first processing condition 91 to the second processing condition 92, the average output of the laser light 23 changes (in the example shown in FIG. 5, it decreases).

In addition, the control unit 54 monitors the transition of the peak output of the laser light 23 for processing based on waveform data including the peak output of the laser light 25 acquired by the photodetector 43 as shown in FIG. 6. Estimate . While laser processing is performed under the first processing conditions 91, the pulse waveform of the laser light 23 is approximately constant. Additionally, while laser processing is performed under the second processing condition 92, the pulse waveform of the laser light 23 is approximately constant. Additionally, by transitioning from the first processing condition 91 to the second processing condition 92, the pulse waveform of the laser light 23 changes (in the example shown in FIG. 6, the peak value decreases).

The control unit 54 multiplies the average output of the laser light 24 acquired by the thermal sensor 42 shown in FIG. 5 by a predetermined coefficient, and calculates the laser light acquired by the photodetector 43 shown in FIG. 6. Set as the threshold value (93) for pulse omission of the waveform data in (25). Therefore, the set threshold 93 changes at the timing when the average output of the laser light 23 changes, that is, at the timing of transition from the first processing condition 91 to the second processing condition 92.

As explained above, in the laser processing device 1 according to the embodiment, a part of the laser light 21 is separated as the inspection laser light 22, and this laser light 22 is received, thereby forming the laser light 22. ) It is possible to perform intensity measurement and pulse observation simultaneously. In this method, a part of the laser light 21 is separated as the laser light 22 for detection and most of the laser light 21 is used as the laser light 23 for processing, so the laser light 21 is used during processing. It becomes possible to determine the status of and improve productivity.

For example, based on the change in the average output of the detected laser light 22 and the change in output, if these fall below a preset threshold, it is possible to estimate a decrease in the output of the laser light for processing 23 and a pulse loss. When the output of the laser light 22 decreases or when pulse loss is observed, it is possible to stop processing to avoid total damage to the workpiece 100. In addition, it is also possible to save various sensor values before and after the moment an abnormality is observed as logs and use them for abnormality analysis. Here, the various sensor values include information such as insufficient voltage, current, and temperature in the optical element inside the laser oscillator 30, and information such as temperature and humidity within the optical box. Additionally, by accumulating these data, they can be used to predict or prevent the occurrence of defects.

In addition, by detecting the average output of the laser light 23 and the change in output, and automatically setting the threshold for detecting pulse omission based on the average output, the processing conditions can be changed during processing and the appropriate threshold value can be changed. It is also applicable in this case.

Additionally, the present invention is not limited to the above embodiments. In other words, the present invention can be implemented with various modifications without departing from the gist of the present invention. For example, the control unit 54 may output information acquired by the detection unit 50, and the operator may determine whether the device is operating normally based on the output information. For example, the control unit 54 may simply output the threshold value for detecting pulse omission set based on the average output acquired by the thermal sensor 42 and the waveform data acquired by the photo detector 43, and the output Based on the information provided, the operator may determine the presence or absence of pulse omission.

1: Laser processing device 10: Holding table
20, 20-1: Laser light irradiation unit 21, 22, 23, 24, 25: Laser light
30, 30-1: laser oscillator 31: laser oscillator
32: condenser lens 33: separation member
40, 40-1: light receiving unit 41: branch mirror
42: thermal sensor 43: photo detector
44: condenser lens 45: wavelength selection filter
46: ND filter 50: detection unit
51: signal amplification unit 52: pulse waveform information acquisition unit
53: Light intensity information acquisition unit 54: Control unit
91: first processing condition 92: second processing condition
93: Threshold 100: Workpiece

Claims (5)

As a laser processing device,
A laser oscillator that generates laser light,
a condensing lens that focuses the laser light generated by the laser oscillator;
a separation member that separates the laser light generated by the laser oscillator into laser light for inspection and laser light for processing to focus the laser light on a workpiece;
a light receiving unit that receives the inspection laser light separated by the separation member;
a detection unit that acquires information about the intensity of the laser light and information about the pulse waveform of the laser light from the laser light received by the light receiving unit;
A control unit that outputs information acquired by the detection unit
A laser processing device comprising: The method of claim 1, further comprising a branch mirror for branching the inspection laser light separated by the separation member,
The light receiving unit,
a thermal sensor that receives one laser beam diverged by the branching mirror and measures an average output of the laser beam;
A photo detector that receives the other laser beam diverged by the branching mirror and acquires information about the pulse waveform of the laser beam.
A laser processing device, characterized in that it has. The method of claim 2, wherein the thermal sensor receives the laser light reflected by the diverging mirror,
The laser processing device is characterized in that the photodetector is arranged to receive the laser light that has passed through the branch mirror. The laser processing device according to claim 3, wherein an ND filter is disposed between the branch mirror and the photodetector. The method according to any one of claims 1 to 4, wherein the information about the pulse waveform of the laser light acquired by the detection unit includes information about the presence or absence of pulse omission,
The laser processing device is characterized in that the control unit automatically sets a threshold value for detecting pulse omission based on the average output of the laser light.

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