TWI692384B - Laser processing device and laser processing method - Google Patents

Abstract

[Problem] The present invention aims to shorten the processing time when processing is performed on a substrate. [Solution] On a laser processing device having a laser oscillator that oscillates a laser pulse wave, and an acousto-optic modulator that extracts a processing pulse wave based on the laser pulse wave output from the laser oscillator It is characterized in that: a control section for controlling the acousto-optic modulator is provided for extracting a plurality of processing pulse waves with different energies for each successive laser pulse wave during the oscillation period of the laser pulse wave , A processing position will be processed with the above-mentioned complex processing pulse wave taken from the same laser pulse wave.

Description

Laser processing device and laser processing method

The present invention relates to a laser processing apparatus and a laser processing method for performing processing on a substrate using laser.

For example, in the case where drilling is performed on the substrate where the metal layer is laminated on the resin layer, as disclosed in Patent Document 1, the metal layer is drilled by the laser pulse wave from the preceding section of the laser oscillator Afterwards, the method of drilling the resin layer under the holed metal layer by the laser pulse wave in the back stage. However, this method has the disadvantage of long processing time due to the use of separate laser pulses on the metal layer and the resin layer. In contrast, there is a method of taking out two laser pulses for metal layer processing and resin layer processing from one laser pulse wave oscillated from the laser oscillator, however, the laser pulse wave is attenuated Two types of laser pulses for processing were taken before the start. With this method, it is necessary to lengthen the period before the attenuation of the laser pulse wave. This method must lengthen the period of the laser pulse wave in terms of the characteristics of the laser oscillator. As a result, the processing time becomes longer. [Advanced technical documents] [Patent documents]

[Patent Document 1] Japanese Patent Laid-Open No. 2001-313471

The purpose of the present invention is to shorten the processing time when processing is performed on the substrate.

Among the inventions disclosed in this patent application, a representative laser processing device has a laser oscillator that continuously oscillates a laser pulse wave, and inputs each of the aforementioned laser pulse waves to the laser The acousto-optic modulator for outputting each of the laser pulse waves in the direction of the scanning device or other directions is characterized in that a control unit for controlling the acousto-optic modulator is arranged such that for each continuous When the pulse wave is output from the acousto-optic modulator in the direction of the laser scanning device during the oscillation period of the laser pulse wave, the energy can be output as a plurality of processes by changing the energy in only a single direction The control is performed in a pulse manner, and the plurality of processing pulses are continuously irradiated to the same processing position.

In addition, among the inventions disclosed in this patent application, a representative laser processing method is to continuously input laser pulses of a laser oscillator into an acousto-optic modulator, and use the aforesaid acousto-optic modulator toward the laser. The direction of the scanning device or other directions output each continuous laser pulse wave, characterized in that, for each continuous laser pulse wave, the acousto-optic modulation is performed during the oscillation period of the laser pulse wave When the device outputs in the direction of the laser scanning device, the acousto-optic modulator is controlled in such a manner that the energy can be changed in a single direction and output as a plurality of processing pulses, and the plurality of processing pulses are continuous Irradiated in the same processing position.

According to the present invention, the plural processing pulse waves are taken out from one laser pulse wave, so the processing time can be shortened.

1: substrate

2: laser oscillator

3: AOM

4: Galvano scanner

5: gate

6: Overall control department

7: Laser Shock Control Department

8: AOM control department

9: Galvano Control Department

22, 24: metal layer

23: resin layer

25: Hole

D: AOM drive signal

G: Galvano motion control signal

L1~L3: Laser pulse wave

S: Laser shock command signal

[Figure 1] is a timing diagram of a laser drilling apparatus according to an embodiment of the present invention.

[Figure 2] is a block diagram of a laser drilling apparatus according to an embodiment of the present invention.

[FIG. 3] It is a cross-sectional view for explaining the processing by a laser drilling device according to an embodiment of the present invention.

[Example]

Fig. 2 is a block diagram of a laser drilling device according to an embodiment of the invention. In Fig. 2, the substrate 1 on which drilling should be performed is placed on a table top not shown. 2 is a laser oscillator that oscillates the laser pulse wave L1. 3 is the acousto-optic modulator (hereinafter abbreviated as AOM) that divides the laser pulse wave L1 output from the laser oscillator 2 into the processing direction and the non-processing direction, and 4 is the laser beam that will be divided into the processing direction at AOM3. The pulse wave L2 illuminates the Galvano scanner at the drilling position of the substrate 1. The Galvano scanner 4 scans the laser pulse wave L2 by rotation. 5 is a damper that absorbs the laser pulse wave L3 that is diverged in the non-machine direction in AOM3.

6 is an overall control unit that controls the overall operation of the device, and is realized by a processing device controlled by a program, for example, and includes several elements. 7 is the laser oscillation control section that outputs the oscillating laser oscillation command signal S of each laser pulse wave L1 in the laser oscillator 2 and 8 is the AOM control section that outputs the AOM drive signal D that controls the divergence action of AOM3 , 9 is a Galvano control section that outputs a Galvano operation control signal G indicating the operation of the Galvano scanner 4. Some or all of these control units may be provided separately from the entire control unit 6. In addition, in FIG. 2, each constituent element or connecting line is mainly displayed in consideration of the need to explain this embodiment, and it does not mean that the laser drilling apparatus is required to display all of it.

Figure 1 is a timing diagram of the laser drilling apparatus shown in Figure 2.

The Galvano motion control signal G is turned on each time the hole processing at the new position is performed to rotate the Galvano galvano scanner 4 and to stop the Galvano scanner 4 when it is turned off. Once Galvano is in motion The control signal G becomes off, and the laser oscillation command signal S is turned on for a predetermined time, and the laser pulse wave L1 from the laser oscillator 2 starts to rise. Once the laser oscillation command signal S becomes off, the laser oscillator 2 becomes The attenuation of the laser pulse wave L1 begins.

Once the laser oscillation command signal S is turned on, the AOM drive signal D is turned on for t2 time after turning on at time t1, and once the laser oscillation command signal S becomes off, the AOM drive signal D is turned on after t3 time after turning off Turn on t4 time. In the time zone when the AOM drive signal D is turned on, the laser pulse wave L1 input to AOM3 is diverged to the processing direction and given to the Galvano scanner 4 as the laser pulse wave L2. In the time zone when the AOM drive signal D is turned off, the laser pulse wave L1 input to the AOM3 is diverted to the non-processing direction and given to the shutter 5 as the laser pulse wave L3.

That is, in this embodiment, during the period when the laser pulse wave L1 is output from the laser oscillator 2 for processing a hole, before the energy of the laser pulse wave L1 becomes the peak value, that is, before the laser The specific time band t2 before the attenuation of the pulse wave L1 starts, and the energy of the laser pulse wave L1 passes the peak value, that is, the specific time band t4 after the attenuation of the laser pulse wave L1 starts, a total of two AOM driving signals D is output back and forth.

In addition, once the second AOM drive signal D becomes off, the electrical operation control signal G becomes on, and in order to perform the hole processing at the new position, the Galvano scanner 4 starts to rotate.

FIG. 3 is a cross-sectional view for explaining the processing performed when drilling a substrate on which a metal layer is laminated on a resin layer according to the laser drilling apparatus described above. (a) indicates the state before processing, (b) indicates the state during processing, and (c) indicates the state after processing. In FIG. 3, 22 is a metal layer made of copper foil, for example, on the surface side of the substrate to be perforated, 23 is a resin layer under the metal layer 22, and 24 is under the resin layer 23, for example A metal layer made of copper foil.

Once through the above laser drilling position, as shown in the first figure, the laser pulse wave L2 with a large critical value of the output energy is output at a specific time zone t2 during the period before the attenuation of AOM3 begins. Therefore, As shown in FIG. 3(b), mainly the critical value of the processing energy on the surface side of the substrate 1 is high The metal layer 22 is processed. After that, as shown in FIG. 3(c), in the specific time period t4 after the start of the next decay, mainly the resin layer 23 with a low critical value of the processing energy is processed, and finally reaches the hole 25 of the metal layer 24 form.

According to the above embodiment, when drilling is performed on the substrate 1 on which the metal layer 22 is laminated on the resin layer 23, before the attenuation of the laser pulse wave L1 oscillated by the laser oscillator 2 starts, The metal layer 22 is processed, and the resin layer 23 is processed during the period after the attenuation starts, so the period until the attenuation of the laser pulse wave L1 does not become particularly long, and only one laser pulse wave can be borrowed , Both the metal layer 22 and the resin layer 23 are processed.

In addition, on the resin layer 23 having a low critical value of processing energy, the extracted laser pulse for processing is used during the period after the attenuation starts to be small, so the energy is too large, and it will not cause the shape of the hole in the resin layer 23 Get worse.

Therefore, high-speed and high-quality hole processing can be realized.

In the above, the present invention has been described by taking the embodiment as the main body. The embodiment is an example for easy understanding of the present invention, and various modifications can be implemented by replacing the constituent elements in the embodiments or adding other kinds of elements. Therefore, the present invention is not limited to the examples.

For example, in the above embodiment, the AOM drive signal D is turned on only once during the period after the attenuation starts, but it is also possible to perform the plural processing by turning on the AOM drive signal D twice during the period. This method can alleviate the impact on the resin layer 23, and can drill holes of good quality in this area. In addition, the impact on the metal layer 24 can be suppressed.

In the above embodiment, the case where the metal layers 22 and 24 on which the respective metal layers 22 and 24 are laminated is perforated is described. However, it is also possible to use a laminated substrate of other materials having different critical values of processing energy. For example, the resin layer 23 may be replaced with a ceramic layer.

D‧‧‧AOM drive signal

G‧‧‧GALVANO action control signal

L1, L2‧‧‧Laser pulse

S‧‧‧Laser shock command signal

t1~t4‧‧‧time

Claims (5)

A laser processing device has a laser oscillator that continuously oscillates a laser pulse wave, and inputs each of the continuous laser pulse waves and outputs each of the above in the direction of the laser scanning device or other directions The acousto-optic modulator of the laser pulse wave is characterized in that the control unit for controlling the acousto-optic modulator is configured to, for each continuous laser pulse wave, oscillate in the laser pulse wave When outputting from the acousto-optic modulator in the direction of the laser scanning device during the period, control is performed in such a way that the energy can be changed in a single direction and output as a plurality of processing pulses; Continuously irradiate the same processing position with pulses. The laser processing device as described in item 1 of the patent application range, wherein the complex processing pulse wave system output from the acousto-optic modulator reduces the energy of the subsequent processing pulse wave to the previous processing The energy of the pulse wave is low. A laser processing method, the laser pulse wave of the continuous vibration of the laser oscillator is input to the acousto-optic modulator, and each continuous aforesaid is outputted in the direction of the laser scanning device or other directions with the acousto-optic modulator The laser pulse wave is characterized in that, for each successive laser pulse wave, during the oscillation period of the laser pulse wave, it is output from the acousto-optic modulator in the direction of the laser scanning device, The acousto-optic modulator is controlled in such a way that the energy can be changed in a single direction and output as a plurality of processing pulses; the plurality of processing pulses are continuously irradiated to the same processing position. The laser processing method as described in item 3 of the patent application scope, wherein the complex processing pulse wave system output from the acousto-optic modulator reduces the energy of the subsequent processing pulse wave to the previous processing The energy of the pulse wave is low. The laser processing method as described in item 4 of the patent application range, wherein in the case of processing a substrate on which a metal layer is laminated on a resin layer, the metal layer is mainly processed by the preceding processing pulse wave, by the above The subsequent processing pulse wave mainly processes the above resin layer.

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