JP2021098214A - Control device of laser beam machine and laser beam machining method - Google Patents

Abstract

To provide a control device of a laser beam machine which can suppress deterioration in stability of pulse energy even when a repeated frequency of a pulse is varied.SOLUTION: A control device controls a laser beam machine which supplies high frequency power to a discharge electrode of a pulse laser oscillator from a power source, scans an object to be machined with a pulse laser beam output by a beam scanner so that the pulse laser beam output from the pulse laser oscillator incidents on a plurality of points to be machined of the object to be machined in order, and performs laser beam machining. When distribution of the points to be machined of the object to be machined to be laser machined next is different from distribution of the points to be machined of the object to be machined subjected to laser machining just before, the control device controls the power source so that voltage of high frequency power supplied to the discharge electrode becomes a voltage target value before the object to be machined that is machined next is subjected to laser machining.SELECTED DRAWING: Figure 6

Description

The present invention relates to a control device for a laser processing machine and a laser processing method.

There is known a laser processing machine that performs processing by reflecting laser light with a galvano mirror, condensing it with a condensing lens, and irradiating an object to be processed such as a substrate (Patent Document 1). For example, this laser machine is used for drilling holes in a printed circuit board. In the laser processing machine disclosed in Patent Document 1, the galvano mirror is positioned at a target rotation angle, and after the positioning of the galvano mirror is completed, the laser beam is applied to the workpiece. As the laser light source, a carbon dioxide laser oscillator that outputs a pulsed laser beam is used.

Japanese Unexamined Patent Publication No. 2004-66300

Generally, since the distance from the work point where the laser beam was incident immediately before to the work point where the laser beam should be incident next is not constant, the time from the start of operation of the galvanometer mirror to the completion of positioning varies. As a result, the repetition frequency of the pulse of the pulsed laser beam output from the laser oscillator fluctuates. Fluctuations in the repetition frequency of the pulse result in reduced stability of the pulse energy.

An object of the present invention is to provide a control device and a laser processing method for a laser processing machine capable of suppressing a decrease in stability of pulse energy even if the repetition frequency of a pulse fluctuates.

According to one aspect of the invention
A high-frequency power is supplied from the power source to the discharge electrode of the pulse laser oscillator, and the pulse laser beam is sequentially incident on a plurality of work points of the workpiece so that the pulse laser beam output from the pulse laser oscillator is incident on the plurality of workpieces. It is a control device of a laser processing machine that scans and performs laser processing.
When the distribution of the workpieces of the object to be machined next to be laser-machined is different from the distribution of the points to be machined of the object to be machined immediately before, before laser machining the next object to be machined. Provided is a control device for a laser machine that controls the power supply so that the voltage of the high frequency power supplied to the discharge electrode becomes a voltage target value.

According to another aspect of the invention
A high-frequency power is supplied to the discharge electrode of the pulse laser oscillator to output the pulse laser beam, and the beam scanner is operated to move the incident position of the pulse laser beam on the surface of the object to be processed to move the incident position of the pulse laser beam to a plurality of work points. It is a laser processing method in which a pulsed laser beam is incident on the
The voltage of high-frequency power supplied to the discharge electrode when the distribution of a plurality of workpieces of the object to be machined immediately before and the distribution of a plurality of points to be machined of the object to be machined next are different. A laser machining method for machining an object to be machined next is provided.

When processing substrates with different distributions of work points, the average value of the pulse repetition frequency of the pulsed laser beam is also different. When the control device of the laser machining machine is used to process a substrate of a substrate type having a different distribution of processing points, a high-frequency power voltage is used for each substrate type (that is, for each average value of pulse repetition frequencies, etc.). It becomes possible to set a target value. By setting a preferable voltage target value for each substrate type, it is possible to reduce the degree of variation in pulse energy.

FIG. 1 is a block diagram of a laser processing machine according to this embodiment. FIG. 2 is a cross-sectional view of the pulse laser oscillator. FIG. 3 is an equivalent circuit diagram of a high frequency power supply. FIG. 4A is a diagram showing an example of the distribution of a plurality of work points defined on the surface of the substrate, and FIG. 4B is a diagram showing an example of the processing order of the plurality of work points. FIG. 5 is a timing chart showing the temporal relationship between the operation of the beam scanner and the output of the pulsed laser beam. FIG. 6 is a timing chart showing the temporal relationship between the processing period for each substrate type, the processing period for each substrate, and the timing at which the control device sets the voltage target value in the power supply when processing a plurality of substrates. FIG. 7 is a flowchart showing the process of the laser machining method according to the embodiment. FIG. 8 is a flowchart showing the process of the laser machining method according to another embodiment, which is an alternative to step SA3 of FIG.

A laser machining machine and a laser machining method according to an embodiment will be described with reference to FIGS. 1 to 7.

FIG. 1 is a block diagram of a laser processing machine according to this embodiment. The power supply 30 applies a high frequency voltage P to the discharge electrode 11 of the pulse laser oscillator 10 in a pulsed manner. The power supply 30 includes a DC power supply 32 having a variable output voltage and a high frequency power supply 31. For the pulse laser oscillator 10, for example, a carbon dioxide laser oscillator is used. The laser control device 41 uses the DC power supply 32 so that the voltage of the high frequency power supplied by the high frequency power supply 31 to the discharge electrode 11 becomes the voltage target value V1 based on the voltage target value V1 commanded by the processing machine control device 42. Control. Further, the laser control device 41 controls the high frequency power supply 31 based on the output timing command ST from the processing machine control device 42.

When high-frequency power is supplied from the power source 30 to the discharge electrode 11, plasma is excited between the discharge electrodes 11, and the pulse laser beam Lp is output from the pulse laser oscillator 10. The pulsed laser beam Lp output from the pulsed laser oscillator 10 is branched into a transmitted beam and a reflected beam by the partial reflecting mirror 61. The reflected beam is incident on the photodetector 62. The photodetector 62 outputs a detection value Dv according to the light intensity of the incident light. The detected value Dv is input to the laser control device 41.

The transmitted beam transmitted through the partial reflector 61 passes through the light guide optical system 63 and the aperture 64 and is incident on the acoustic optical element (AOD) 65. The light guide optical system 63 includes, for example, a beam expander and the like. The acoustic optical element 65 directs the incident pulse laser beam to any one of the first path 70A, the second path 70B, and the path toward the beam damper 71 in response to a command from the processing machine control device 42. The pulsed laser beam directed to the first path 70A passes through the beam scanner 67A and the condenser lens 68A and is incident on the substrate 90 which is the object to be processed. The pulsed laser beam directed to the second path 70B is reflected by the folded mirror 66, passes through the beam scanner 67B and the condenser lens 68B, and is incident on the other substrate 90 to be processed. Drilling is performed by injecting a pulsed laser beam onto each of the two substrates 90. The board 90 is, for example, a printed wiring board.

As the beam scanners 67A and 67B, for example, a galvano scanner including a pair of swing mirrors is used. The beam scanners 67A and 67B are instructed by the processing machine control device 42.
The incident position of the pulsed laser beam is moved on the surface of each of the two substrates 90. As the condenser lenses 68A and 68B, for example, an fθ lens is used.

The two substrates 90 are supported by the horizontal support surface of the movable stage 80. The movable stage 80 moves the two substrates 90 in a two-dimensional direction parallel to the support surface by a command from the processing machine control device 42.

From the input device 45 to the processing machine control device 42, an operation command for the laser processing machine and various data necessary for laser processing are input.

FIG. 2 is a cross-sectional view of the pulse laser oscillator 10. A blower 18, a pair of discharge electrodes 11, a heat exchanger 17, and a laser medium gas are housed inside the laser chamber 19. A discharge space 14 is defined between the pair of discharge electrodes 11. The laser medium gas is excited by the electric discharge generated in the discharge space 14. FIG. 2 shows a cross section orthogonal to the length direction of the discharge electrode 11. Each of the discharge electrodes 11 includes a conductive member 12 and a ceramic member 13. The ceramic member 13 separates the conductive member 12 from the discharge space 14.

A circulation path from the blower 18 to the blower 18 via the discharge space 14 and the heat exchanger 17 is formed in the laser chamber 19. The heat exchanger 17 cools the laser medium gas that has become hot due to electric discharge.

A pair of terminals 15 are attached to the wall surface of the laser chamber 19. The conductive members 12 of the discharge electrode 11 are each connected to the terminal 15 by the current path 16 in the chamber. The terminal 15 is connected to the power supply 30 by the current path 20 outside the chamber.

FIG. 3 is an equivalent circuit diagram of the high frequency power supply 31. The high frequency power supply 31 includes an H-bridge circuit having two bridge arms 35A and 35B. Each of the bridge arms 35A, 35B includes two switching elements connected in series with each other. The discharge electrode 11 is connected to the midpoint between the two bridge arms 35A and 35B via the transformer 35C. The DC power supply 32 applies a DC voltage to the H-bridge circuit. The laser control device 41 controls the voltage value of the DC voltage output from the DC power supply 32, and also controls the on / off of the switching element. By controlling the on / off of the switching element, high frequency power is supplied to the discharge electrode 11. The voltage of high frequency power depends on the output voltage of the DC power supply 32.

FIG. 4A is a diagram showing an example of the distribution of a plurality of work points 93 defined on the surface of the substrate 90. FIG. 4A shows only a part of the plurality of work points 93. The distribution of the plurality of work points 93 defined on the two substrates 90 supported by the movable stage 80 (FIG. 1) is the same. The outer shape of the substrate 90 is, for example, a rectangle.

Alignment marks 91 are provided at each of the four corners of the rectangular substrate 90. A plurality of work points 93 are defined on the surface of the substrate 90. In FIG. 4A, the work point 93 is indicated by a circular symbol, but in reality, the surface of the substrate 90 is not marked in any way, and the positions of the plurality of work points 93 are defined. The data is stored in the processing machine control device 42.

A plurality of scan areas 92 are defined on the surface of the substrate 90. Each shape of the scan area 92 is square, and its size is substantially equal to the size of the range in which the beam scanners 67A and 67B (FIG. 1) can be operated to move the pulsed laser beam. The plurality of scan areas 92 are arranged so as to include all the work points 93 on the substrate 90 within one of the scan areas 92. The plurality of scan areas 92 may partially overlap, and the scan area 92 may not be arranged in an area where the work points 93 are not distributed.

By moving one scan area 92 directly under one of the condenser lenses 68A and 68B (FIG. 1) and sequentially incident a pulsed laser beam on a plurality of work points 93 in the scan area 92, the pulse laser beam is incident on the plurality of work points 93. The scan area 92 is processed. When the processing of one scan area 92 is completed, the movable stage 80 (FIG. 1) is operated to move the scan area 92 to be processed next directly under one of the condenser lenses 68A and 68B. During the machining of one scan area 92, the movable stage 80 is stationary. In FIG. 4A, the processing order of one scan area 92 is indicated by an arrow.

FIG. 4B is a diagram showing an example of the processing order of the plurality of work points 93. A serial number is assigned to a plurality of work points 93. One scan area 92 is processed by operating the beam scanners 67A and 67B (FIG. 1) and injecting a pulsed laser beam into a plurality of processing points 93 in the order of serial numbers. In FIG. 4B, the machining order of the plurality of work points 93 is indicated by arrows. The processing order of the work point 93 is determined so that, for example, the movement path of the incident position of the pulsed laser beam is the shortest.

An arbitrary set of a plurality of work points 93 existing in one scan area 92 and being machined under the same conditions is called a "block". The serial number is assigned to a plurality of work points 93 for each block. The process of injecting laser pulses into all the work points 93 of one block in order under the same irradiation conditions is called "scanning". The number of irradiation conditions when processing the work point 93 of one block is called "the number of cycles".

All of the plurality of work points 93 to be machined under the same conditions may be included in one block, or some work points 93 of the plurality of work points 93 to be machined under the same conditions may be included in one block. May be good. When a part of the work point 93 is included in one block, an arbitrary set of a plurality of other work points 93 not included in the block may be included in the other block. The combination of the plurality of work points 93 included in one block may be the same for the plurality of substrates 90 (FIG. 4A), or may be different for each substrate 90.

For example, in the processing of one cycle and one scan, one scan is performed under one irradiation condition. In the processing of one cycle and two scans, two scans are performed under the same irradiation conditions. At this time, the laser pulse is incident on one work point 93 twice in total. In the two-cycle processing, scanning under the first irradiation condition and scanning under the second irradiation condition different from the first irradiation condition are performed. The pulse width of the pulsed laser beam used differs between the first irradiation condition and the second irradiation condition. For example, in the processing of the first cycle 2 scans and the second cycle 1 scan, two scans are performed under the first irradiation condition, and then one scan is performed under the second irradiation condition.

FIG. 5 is a timing chart showing the temporal relationship between the operation of the beam scanners 67A and 67B (FIG. 1) and the output of the pulsed laser beam Lp. The processing machine control device 42 starts the operation of the beam scanners 67A and 67B (time t ₁ ). When the positioning of the incident position of the pulsed laser beam is completed (time t ₂ ), the beam scanners 67A and 67B notify the processing machine control device 42 of the completion of setting. Upon receiving the notification of the completion of the setting, the processing machine control device 42 sends an output timing command ST (FIG. 1) to the laser control device 41.

When the laser control device 41 detects the output timing command ST, the laser control device 41 operates the high-frequency power supply 31 for a time corresponding to a predetermined pulse width to supply high-frequency power to the discharge electrode 11. As a result, the laser pulse of the pulsed laser beam Lp rises, and the laser pulse falls when a time corresponding to a predetermined pulse width elapses (time t ₃ ). The processing machine control device 42 operates the acoustic optical element 65 to move the laser pulse LpA toward the first path 70A (FIG. 1) and the laser pulse LpB toward the second path 70B (FIG. 1) from one laser pulse. And cut out. The laser beam in a time zone other than the time zone in which the two laser pulses LpA and LpB are cut out from one laser pulse is directed to the beam damper 71 (FIG. 1).

When the laser pulse falls (time t ₃ ), the processing machine control device 42 starts the operation of the beam scanners 67A and 67B (FIG. 1), and the incident position of the pulsed laser beam Lp is changed to the processing to be processed next. Move to the position of point 93 (FIG. 4B). For example, the time point at which a time corresponding to a predetermined pulse width elapses from _{the rise time t 2} may be _{set as the fall time t 3 of the laser pulse.} In this way, the control device 40 repeats the control of moving the incident position of the pulsed laser beam Lp to the next processing point and the control of outputting the laser pulse from the pulsed laser oscillator 10 (FIG. 1). One scan area 92 (FIG. 4A) is machined.

Since the distance from the work point 93 processed immediately before to the work point 93 to be processed next is not constant, the time required to move the incident position of the pulsed laser beam is also not constant. Therefore, the output cycle of the laser pulse is not constant. That is, the repetition frequency of the pulse of the pulsed laser beam Lp is not constant. In the present specification, the "pulse repetition frequency of the pulsed laser beam" may be simply referred to as the "frequency of the pulsed laser beam".

FIG. 6 is a timing chart showing the temporal relationship between the processing period for each substrate type when processing a plurality of substrates, the processing period for each substrate, and the timing at which the control device 40 sets the voltage target value V1 in the power supply 30. Is. A plurality of substrates _A 1 of the substrate type _{A, A 2, A 3,} ··· A n processed sequentially, then a plurality of substrates _B 1 of the substrate type _{B, B 2, B 3,} ··· B m Are processed in order. In the laser processing machine shown in FIG. 1, two substrates are processed at the same time in the first path 70A and the second path 70B. For a plurality of substrates of the same substrate type, the distribution of the plurality of work points 93 (FIG. 4A) is the same. The distribution of the plurality of work points 93 (FIG. 4A) is different between the substrates having different substrate types.

The first substrate of a substrate type, for example, a substrate A ₁ of the substrate type _A, performs idling before performing processing for the substrate B ₁ of the substrate type B. In the idle operation, the pulse laser oscillator 10 is not operated, and the beam scanners 67A and 67B are operated based on the position data that defines the distribution of the processed points 93 of the substrate to be processed next. The pulsed laser beam is not output during idle operation, but from the time when the positioning of the beam scanners 67A and 67B is completed (time t _{2 in} FIG. 5), the time when the next operation of the beam scanners 67A and 67B starts (time in FIG. 5). Until t ₃ ), the delay is made by a time corresponding to the pulse width. As a result, the incident position of the pulsed laser beam can be moved under the same conditions as when the pulsed laser beam is output. Therefore, it can be considered that the pulsed laser beam is virtually output during idle operation. This idle operation is performed on all the scan areas 92 (FIG. 4A) defined on the substrate 90, but it is not necessary to operate the movable stage 80.

When the idle operation is completed, the control device 40 obtains the voltage target value V1 based on the average value of the frequencies of the virtual pulsed laser beams and the like. The relationship between the average value of the frequencies of the virtual pulsed laser beams and the voltage target value V1 is stored in advance in the control device 40. This relationship is stored, for example, in the form of a discrete numeric table. The voltage target value V1 can be obtained by performing an interpolation calculation from the average value of the frequencies of the virtual pulsed laser beam and the numerical table. The control device 40 commands the DC power supply 32 to set the voltage target value V1 so that the voltage of the high-frequency power supplied to the discharge electrode 11 becomes the voltage target value V1.

FIG. 7 is a flowchart showing the process of the laser machining method according to the embodiment.
First, the substrate 90, which is the object to be processed, is supported by the movable stage 80 (FIG. 1) (step SA1). Specifically, a loader (not shown) carries out the substrate 90 from a cart in which a plurality of unprocessed substrates 90 are stocked, conveys the substrate 90 onto the movable stage 80, and places the substrate 90 on the support surface of the movable stage 80. After that, the movable stage 80 attracts the substrate 90. After suction, the alignment mark 91 (FIG. 4A) of the substrate 90 is detected, and the position of the substrate 90 with respect to the movable stage 80 is obtained.

Next, the processing machine control device 42 operates the beam scanners 67A and 67B to perform idle operation (FIG. 6), and determines the voltage target value V1 based on the information depending on the positions of the plurality of processing points 93. (Step SA2). The idling corresponds to idling before performing the processing of the substrate A ₁ of the substrate type A in FIG. As the information depending on the positions of the plurality of work points 93, for example, the average value of the frequencies of the virtual pulsed laser beams during the idle operation period is adopted.

Here, the "frequency of the pulsed laser beam" when the pulse interval is not constant means the inverse of the elapsed time from the rise of the laser pulse to the rise of the next laser pulse, and the two laser pulses arranged on the time axis. On the other hand, one frequency is determined. The “average frequency of the pulsed laser beam” is, for example, the total operating time of the beam scanners 67A and 67B during idle operation (that is, the total moving time of the incident position of the pulsed laser beam), the pulse width, and the like. And it can be calculated based on the number of work points 93.

The relationship between the average value of the frequencies of the pulsed laser beams and the voltage target value V1 is stored in advance in the processing machine control device 42. When the voltage target value V1 is determined, the laser control device 41 controls the DC power supply 32 so that the voltage of the high frequency power supplied from the power supply 30 to the discharge electrode 11 becomes the voltage target value V1.

With the power supply 30 set so that the high frequency power of the voltage target value V1 is supplied to the discharge electrode 11, the control device 40 is movable with the high frequency power supply 31, the acoustic optical element 65, the beam scanners 67A and 67B, and By controlling the stage 80, the substrate 90 is processed (step SA3). This processing corresponds to the processing of the substrate A ₁ shown in FIG. When the processing of the substrate 90 is completed, the processing machine control device 42 determines whether or not the unprocessed substrate 90 of the same type remains (step SA4).

When an unprocessed substrate 90 of the same type remains, the processing machine control device 42 operates an unloader (not shown) to carry out the processed substrate 90 from the movable stage 80, and loader (not shown). The unprocessed substrate 90 of the same type is carried into the movable stage 80 and supported by the movable stage 80 (step SA5). This process is, for example, the substrate is carried out A ₁ shown in FIG. 6 corresponds to a process of loading the substrate A _2. After that, the processing of the substrate 90 is executed (step SA3).

When the raw substrate 90 of the same type does not remain, the processing machine control device 42 determines whether or not the raw substrate 90 of a different type remains (step SA6). When the raw substrate is exhausted, the operation of the laser processing machine is terminated. When a different type of unprocessed substrate 90 remains, the processing machine control device 42 operates an unloader (not shown) to carry out the processed substrate 90 from the movable stage 80, and loader (not shown). The unprocessed different types of substrates 90 are transported to the movable stage 80 and supported by the movable stage 80 (step SA7). This process, for example, a substrate A _n is unloaded as shown in FIG. 6 corresponds to a process of loading the substrate B _1.

After that, the processing machine control device 42 performs idle operation using the position data of the plurality of processing points 93 of the substrate 90 to be processed next, and determines the voltage target value V1. The idling corresponds to idling before performing the processing of the substrate B ₁ shown in FIG.

Next, the excellent effect of the above embodiment will be described.
As a method different from this embodiment, a pulsed laser beam is output at a constant pulse repetition frequency, and a laser pulse during a period in which positioning by the beam scanners 67A and 67B is not completed is input to the beam damper 71 (hereinafter referred to as a method). , A method based on a comparative example.) Is known. In this method, since the completion of positioning by the beam scanners 67A and 67B and the rise of the next laser pulse are not synchronized, a wasted time is generated from the completion of positioning to the rise of the laser pulse.

On the other hand, in this embodiment, as shown in FIG. 5, the laser pulse rises when the positioning of the incident position of the pulsed laser beam by the beam scanners 67A and 67B is completed. Therefore, no wasted time is generated from the completion of positioning to the rise of the laser pulse. As a result, the processing time can be shortened as compared with the method according to the above comparative example.

When the pulse repetition frequency is not constant, the variation in pulse energy tends to be larger under the condition that the pulse width is constant, as compared with the case where the pulse repetition frequency is constant. Variations in pulse energy are factors that cause deterioration in processing quality. By conducting various evaluation experiments, the inventor of the present application has newly discovered that the degree of variation in pulse energy depends on the voltage of high-frequency power supplied to the discharge electrode 11 (FIG. 1). By performing the evaluation experiment a plurality of times by changing the voltage of the high-frequency power, it is possible to find a preferable voltage in which the degree of variation in the pulse energy is small.

However, it has been found that the preferable voltage at which the degree of variation in pulse energy is small changes depending on the average value of the pulse repetition frequencies and the like. Since the average value of the pulse repetition frequency depends on the distribution of the plurality of work points 93 (FIG. 4A) defined on the substrate 90, the preferable voltage of the high frequency power differs depending on the substrate type.

In this embodiment, the average value of the pulse repetition frequencies is measured in step SA2 (FIG. 7), and the voltage target value V1 of the high frequency power is determined based on the result. Therefore, it is possible to set the voltage target value V1 suitable for processing the substrate of the substrate type for each substrate type in which the distribution of the plurality of work points 93 defined on the substrate 90 is different. This makes it possible to reduce the degree of variation in the pulse energy of the pulsed laser beam and improve the processing quality.

Next, a modified example of the above embodiment will be described.
In the above embodiment, the average value of the frequencies of the pulsed laser beams is adopted as the information depending on the position of the work point 93 obtained in step SA2 (FIG. 7). In addition, statistics other than the average value of the frequencies of the pulsed laser beams may be adopted as information depending on the position of the work point 93. For example, the median value, the mode value, and the like may be adopted.

In the above embodiment, the average value of the frequencies of the pulsed laser beam is calculated based on the total value of the moving time of the incident position of the pulsed laser beam during idle operation, the pulse width, and the number of work points 93. When the pulse width is sufficiently shorter than the moving time of the incident position of the pulsed laser beam during idle operation, the total value of the moving time of the incident position of the pulsed laser beam during idle operation is not taken into consideration. The average value of the frequencies of the pulsed laser beams may be calculated based on the number of work points 93.

In the above embodiment, the pulse laser beam is not output from the pulse laser oscillator 10 during the idle operation in step SA2 (FIG. 7), but the pulse laser beam is output during the idle operation to the beam damper 71 (FIG. 1). By making the pulse laser beam incident, the state in which the pulsed laser beam does not reach the substrate 90 may be realized. In this case, the idle operation also serves as the warm-up operation of the pulse laser oscillator 10.

In the above embodiment, the average value of the frequencies of the virtual pulsed laser beams was obtained by performing idle operation, but the pulsed laser beam was obtained based on the position data of a plurality of work points 93 without performing idle operation. The average value of frequencies may be obtained. For example, using the position data of a plurality of work points 93, it is possible to calculate information regarding the distance from each of the plurality of work points to the next work point to be machined. The average value of the frequencies of the pulsed laser beam can be calculated based on the average value of this distance and the moving speed of the incident position of the pulsed laser beam. Instead of the average value, it is also possible to calculate statistics such as the median value and the mode value.

In the above embodiment, the pulsed laser beam is directed to the first path 70A and the second path 70B by the acoustic optical element 65 to process the two substrates 90 at the same time, but the one substrate 90 is processed by only one path. It may be configured to process.

In the above embodiment, the average value of the frequency of the pulsed laser beam is obtained for each substrate type, but the average value of the frequency of the pulsed laser beam may be obtained for each scan area 92 (FIG. 4A). In this case, the optimum voltage target value V1 can be set for each scan area 92. For example, the DC power supply 32 (FIG. 2) is compared with the time required to operate the movable stage 80 (FIG. 1) to move the scan area 92 to be processed next directly under one of the condenser lenses 68A and 68B (FIG. 2). When the time required to change the output voltage of is short, the optimum voltage target value V1 can be set for each scan area 92.

Next, a laser machining machine and a laser machining method according to another embodiment will be described with reference to FIG. Hereinafter, the description of the configuration common to the examples shown in FIGS. 1 to 7 will be omitted.

In the embodiment shown in FIG. 7, the voltage target value V1 of the high frequency power is constant as long as a plurality of substrates of the same type are processed (steps SA3, SA4, and SA5 are repeated). On the other hand, in the embodiment shown in FIG. 8, the voltage target value V1 of the high frequency voltage is corrected even during the period when the same type of substrate is being processed.

FIG. 8 is a flowchart showing the process of the laser machining method according to the present embodiment, which is an alternative to step SA3 of FIG. First, one substrate 90 is processed (step SB1). At this time, the power supply 30 (FIG. 1) is controlled based on the voltage target value V1 of the high frequency power set at the present time.

When the processing of one substrate 90 is completed, the average value of the frequencies of the pulsed laser beams used in the actual processing is obtained (step SB2). For example, the machining time for each scan area 92 is obtained, and the machining time is totaled for all the scan areas 92. The average value of the frequencies of the pulsed laser beams can be calculated based on the total processing time and the number of processing points 93.

The voltage target value V1 of the high frequency power is corrected based on the obtained average value of the frequencies of the pulsed laser beam (step SB3). For example, the laser control device 41 (FIG. 1) outputs the high frequency power of the corrected voltage target value V1 so that the processing machine control device 42 (FIG. 1) calculates the voltage target value V1 and the power supply 30 outputs the corrected voltage target value V1. To control.

Next, the excellent effect of this embodiment will be described. In this embodiment, in order to correct the voltage target value V1 based on the average value of the frequencies of the pulsed laser beams measured during processing, it is possible to supply a more appropriate high frequency power of the voltage target value V1 to the discharge electrode 11. it can. As a result, it becomes possible to further improve the processing quality.

Next, a modification of the present invention will be described. In this embodiment, the average value is used as the statistic of the frequency of the pulsed laser beam, but the median value, the mode value, and the like may also be used.

It goes without saying that each example is exemplary and the configurations shown in different examples can be partially replaced or combined. Similar effects and effects due to the same configuration of a plurality of examples will not be mentioned sequentially for each example. Furthermore, the present invention is not limited to the above-mentioned examples. For example, it will be obvious to those skilled in the art that various changes, improvements, combinations, etc. are possible.

10 Pulse laser oscillator 11 Discharge electrode 12 Conductive member 13 Ceramic member 14 Discharge space 15 Terminal 16 In-chamber current path 17 Heat exchanger 18 Blower 19 Laser chamber 20 Out-of-chamber current path 30 Power supply 31 High frequency power supply 32 DC power supply 35A, 35B Bridge arm 35C Transformer 40 Control device 41 Laser control device 42 Processing machine control device 45 Input device 61 Partial reflector 62 Light detector 63 Light guide optical system 64 Aperture 65 Acoustic optical element (AOD)
66 Folded Mirror 67A, 67B Beam Scanner 68A, 68B Condensing Lens 70A 1st Path 70B 2nd Path 71 Beam Damper 80 Movable Stage 90 Substrate 91 Alignment Mark 92 Scan Area 93 Work Point

Claims (9)

A high-frequency power is supplied from the power source to the discharge electrode of the pulse laser oscillator, and the pulse laser beam is sequentially incident on a plurality of work points of the workpiece so that the pulse laser beam output from the pulse laser oscillator is incident on the plurality of workpieces. It is a control device of a laser processing machine that scans and performs laser processing.
When the distribution of the workpieces of the object to be machined next to be laser-machined is different from the distribution of the points to be machined of the object to be machined immediately before, before laser machining the next object to be machined. , A control device for a laser machine that controls the power supply so that the voltage of high-frequency power supplied to the discharge electrode becomes a voltage target value. Control to operate the beam scanner to move the incident position of the pulsed laser beam to the next processing point, and
The control device for a laser processing machine according to claim 1, further comprising a function of repeating control of outputting a laser pulse from the pulsed laser oscillator after the positioning of the incident position of the pulsed laser beam is completed. The control device for a laser machine according to claim 1 or 2, wherein the voltage target value is determined based on information depending on the positions of a plurality of work points defined in the object to be machined. The information depending on the positions of the plurality of workpieces is such that the incident position of the pulsed laser beam traces the plurality of workpieces of the workpiece in order while the pulsed laser beam does not reach the workpiece. The control of the laser processing machine according to claim 3, which includes statistics on the repetition frequencies of a plurality of virtual laser pulses when the beam scanner is operated and a laser pulse is virtually incident after the positioning of the incident position is completed. apparatus. The laser according to any one of claims 1 to 4, further provided with a function of correcting the voltage target value based on the statistic of the pulse repetition frequency of the pulsed laser beam during laser machining of the object to be machined. Machining machine control device. The information depending on the positions of the plurality of work points includes information regarding the distance from each of the plurality of work points to the next work point to be machined.
A claim further provided with a function of determining the voltage target value based on the statistic of the distance from each of the plurality of work points to the work point to be machined next and the moving speed of the incident position of the pulsed laser beam. Item 2. The control device for a laser processing machine according to any one of Items 1 to 5. A high-frequency power is supplied to the discharge electrode of the pulse laser oscillator to output the pulse laser beam, and the beam scanner is operated to move the incident position of the pulse laser beam on the surface of the object to be processed to move the incident position of the pulse laser beam to a plurality of work points. It is a laser processing method in which a pulsed laser beam is incident on the
The voltage of high-frequency power supplied to the discharge electrode when the distribution of a plurality of workpieces of the object to be machined immediately before and the distribution of a plurality of points to be machined of the object to be machined next are different. A laser machining method that processes the next object to be machined by changing. Before machining the object to be machined next, the beam scanner is operated so that the incident position of the pulse laser beam traces a plurality of work points of the object to be machined next in order. Obtain the statistics of the repetition frequencies of a plurality of virtual laser pulses when the laser pulses are virtually incident after the positioning of the incident position is completed, and based on the obtained statistics, the high-frequency power supplied to the discharge electrode. The laser processing method according to claim 7, wherein the voltage is determined. Obtain statistics on the repetition frequency of the pulse of the pulsed laser beam during machining of the work target, and the distribution of multiple work points of the work target to be machined next is the multiple work of the work target that was machined immediately before. If the distribution is the same as the distribution of the processing points, the voltage of the high-frequency power supplied to the discharge electrode is corrected based on the statistics of the repetition frequency of the pulse obtained by the processing of the processing object processed immediately before. Alternatively, the laser processing method according to 8.

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