TWI675714B - Laser processing device and laser processing method - Google Patents

Abstract

An object of the present invention is to reduce processing time when processing is performed on a substrate.

A laser processing device having an acousto-optic modulator that divides the laser pulse output from the laser oscillator into a processing direction and a non-processing direction includes a branching operation that outputs a branching operation that controls the acousto-optic modulator. Acousto-optic modulator control section of the control signal; the acousto-optic modulator control section is characterized in that the first specific time before the start of the attenuation of the laser pulse and the time after the start of the attenuation of the laser pulse At a second specific time, a branching operation control signal for branching the laser pulse to the processing direction is output.

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 a laser.

For example, in the case where drilling is performed on a substrate in which a metal layer is laminated on a resin layer, as disclosed in Patent Document 1, the metal layer is drilled by a laser pulse wave from a previous stage of the laser oscillator. Then, a method of drilling the resin layer under the metal layer that has been perforated by the laser pulse in the subsequent stage is performed.

However, this method has the disadvantage of long processing time because individual laser pulses are used on the metal layer and the resin layer.

In contrast, there is a method of taking out two laser pulses for processing a metal layer and a resin layer for processing from one laser pulse from a laser oscillator, but the attenuation of the laser pulse is Before the start, two types of laser pulses for processing were taken out. With this method, it is necessary to lengthen the period before the laser pulse attenuation. This method must lengthen the period of the laser pulse in terms of the characteristics of the laser oscillator. As a result, it has the disadvantage of longer processing time.

[Advanced technical documents]

[Patent Document]

[Patent Document 1] JP 2001-313471

It is an object of the present invention to reduce processing time when processing is performed on a substrate.

Among the inventions disclosed in this patent application, the representative laser processing device includes a laser oscillator that oscillates a laser pulse wave, and instructs the laser oscillator to start or attenuate the start of the laser pulse wave oscillation. The radio-oscillation control unit and the acousto-optic modulator that divides the laser pulse wave output from the laser oscillator into a processing direction and a non-processing direction are characterized in that they include an output control unit for controlling the acousto-optic modulator. The acousto-optic modulator control unit of the divergent action control signal; the acousto-optic modulator control unit is configured to start the laser from the oscillation start instruction from the laser oscillation control unit and the laser oscillator. The pulsation of the pulse wave, the specific period in the first period (t2) until the attenuation of the laser pulse by the laser oscillator is started by the attenuation start command, and the laser oscillation control In the specific attenuation period in the second period (t4) after the laser oscillator starts to attenuate the laser pulse and the laser oscillator starts to attenuate the laser pulse, the laser pulse is divided into the processing direction. Operation control signal.

Also, among the inventions disclosed in this patent application, a representative laser processing method is to input laser pulse waves from a laser oscillator given instructions for start of oscillation and start of attenuation into the processing direction and non-processing. The acousto-optic modulator in the direction performs processing by using laser pulses diverging to the processing direction in the acousto-optic modulator, and is characterized in that it is included in the laser oscillation from the oscillation start instruction and the laser oscillation. The first phase of the laser pulse oscillation is started by the device, and the attenuation of the laser pulse is started by the attenuation start command. During the specific period of time (t2), and the first step of processing, and the processing position processed in the first step, the laser pulse is attenuated from the start of the attenuation start command and the laser oscillator. The second step of processing in a specific period in the subsequent second period (t4).

According to the present invention, since the processing pulse wave is taken out from the laser pulse wave after the attenuation starts, it does not cause the laser pulse wave to become long before the attenuation starts, and plural processing is taken out from one laser pulse wave. With pulse wave, it is possible to shorten the processing time when performing processing on the substrate.

1‧‧‧ substrate

2‧‧‧laser oscillator

3‧‧‧AOM

4‧‧‧Galvano scanner

5‧‧‧ Gate

6‧‧‧All control department

7‧‧‧laser shock control unit

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

S‧‧‧laser shock command signal

[Fig. 1] is a timing chart of a laser drilling device according to an embodiment of the present invention.

[Fig. 2] A block diagram of a laser drilling device according to an embodiment of the present invention.

[Figure 3] is a cross-sectional view for explaining the processing of a laser hole-opening 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 present invention. In Fig. 2, the substrate 1 to be drilled is placed on a tabletop (not shown). 2 is a laser oscillator that oscillates the laser pulse wave L1. 3 is the acousto-optic modulator (hereinafter referred to as AOM) that divides the laser pulse wave L1 output from the laser oscillator 2 into the processing direction and the non-processing direction, 4 is the lightning that will be divided into the processing direction at AOM3 The pulse wave L2 irradiates a Galvano scanner at the drilling position of the substrate 1. The Galvano scanner 4 scans the laser pulse L2 by rotation. 5 is absorbed in AOM3 Damper for laser pulse L3 branched into non-machine direction.

6 is an overall control unit that controls the overall operation of the device. For example, it is realized by a program-controlled processing device, which includes several elements. 7 is a laser oscillation control unit that outputs a laser oscillation command signal S that indicates the oscillation of each laser pulse L1 in the laser oscillator 2, and 8 is an AOM control unit that outputs an AOM drive signal D that controls the branching operation of AOM3. 9 is a Galvano control section that outputs a Galvano motion control signal G that instructs the operation of the Galvano scanner 4. Some or all of these control sections may be provided separately from the entire control section 6. In addition, in FIG. 2, each constituent element or connection line is mainly shown in order to explain the necessity of the present embodiment, and the laser drilling device does not necessarily mean that all of them are shown.

FIG. 1 is a timing chart of the laser drilling device shown in FIG. 2.

The Galvano motion control signal G is turned on each time the hole machining at a new position is performed, and the Galvano scanner 4 is rotated, and the Galvano scanner 4 is stopped when closed. Once the Galvano action control signal G is turned off, the laser shock 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 shock command signal S is turned off, the laser shock Device 2 starts the attenuation of laser pulse L1.

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

That is, in the present embodiment, during the laser pulse wave L1 output from the laser oscillator 2 once for processing a hole, before the energy of the laser pulse wave L1 reaches a peak, that is, before the laser AOM drive signal for a specific time zone t2 before the pulse wave L1 begins to decay and the energy of the laser pulse wave L1 after a peak, that is, a specific time zone t4 after the laser pulse L1 begins to decay D is output back and forth.

When the AOM drive signal D is turned off for the second time, the electrical operation control signal G is turned on. In order to perform hole processing at a new position, the Galvano scanner 4 starts to rotate.

FIG. 3 is a cross-sectional view for explaining a process performed when drilling is performed on a substrate on which a metal layer is laminated on a resin layer according to the laser drilling device 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 on the surface side of the substrate to be perforated, for example, a copper foil, 23 is a resin layer below the metal layer 22, and 24 is under the resin layer 23, for example A metal layer made of copper foil.

Once the above laser drilling position is used, as shown in the first figure, the laser pulse wave L2 with a large critical value of output energy at a specific time zone t2 during the period from the start of the attenuation of AOM3, therefore, As shown in FIG. 3 (b), the metal layer 22 having a high critical value of the processing energy located mainly on the surface side of the substrate 1 is processed. After that, as shown in Figure 3 (c), The specific time zone t4 during this period is mainly that the resin layer 23 with a low critical value of the processing energy is processed, and the holes 25 that finally reach the metal layer 24 are formed.

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 from the laser oscillator 2 is started, the The metal layer 22 is processed, and the resin layer 23 is processed during the period after the attenuation starts, so the period before the attenuation of the laser pulse L1 does not become particularly long, and only one laser pulse can be borrowed Both the metal layer 22 and the resin layer 23 are processed.

In addition, on the resin layer 23 with a low critical value of the processing energy, the extracted laser pulse wave is used during the period when the energy after the attenuation is small, so the energy is too large, and the shape of the holes in the resin layer 23 is not caused. Worse.

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

In the foregoing, the present invention has been described mainly by way of examples. The examples are for easy understanding of the examples of the present invention. Various modifications can be implemented by replacing the constituent elements in the embodiments or adding other elements. Therefore, the present invention is not limited to the examples.

For example, in the above embodiment, the AOM driving signal D is turned on only once during the period after the attenuation is started, but it is also possible to perform multiple-turn processing by turning on the AOM driving signal D twice during the period. This method can alleviate the impact on the resin layer 23 and can perform drilling of excellent quality in this area. It is also possible to suppress the impact on the metal layer 24.

Also, in the above embodiments, the case where holes are performed on the substrates in which the respective metal layers 22 and 24 are laminated above and below the resin layer 23 is described, but it may be a laminated substrate of another material having a different critical value of processing energy. For example, ceramics can also be used Layer in place of the resin layer 23.

Claims (5)

A laser processing device includes a laser oscillator that oscillates a laser pulse, a laser oscillation control unit that instructs the laser oscillator to start or attenuate laser pulse oscillation, and oscillates from the laser. The aforesaid laser pulse wave divergence output by the controller is a processing direction and a non-processing direction acousto-optic modulator, which is characterized in that it includes an acousto-optic modulation that outputs a divergent action control signal that controls the divergent action of the acousto-optic modulator The acousto-optic modulator control unit is configured to start from the oscillation start command from the laser oscillation control unit, start the laser pulse oscillation of the laser oscillator, and start from the attenuation. The laser oscillator, the laser oscillator, and the laser oscillator in a specific period of time during the first period (t2) until the laser pulse starts to decay, and the laser oscillator is controlled by the attenuation start command from the laser oscillation control unit. In a specific period of the second period (t4) after the device starts to attenuate the laser pulse wave, a branching operation control signal for diverging the laser pulse wave to the processing direction is output. The laser processing device according to item 1 of the scope of the patent application, wherein the acousto-optic modulator control section outputs the branching operation control signal multiple times during the second period. A laser processing method in which laser pulses from a laser oscillator given instructions for start of oscillation and start of attenuation are input to an acousto-optic modulator divided into a processing direction and a non-processing direction, and the acousto-optic modulation The device performs processing by using a laser pulse wave divided into the above-mentioned processing direction, and is characterized in that the laser pulse wave is oscillated by the oscillation start instruction and the laser oscillator, and is attenuated by the attenuation. The first step of processing in a specific period of the first period (t2) until the laser oscillator starts the attenuation of the laser pulse wave, and the processing position processed in the first step is determined by The second step of processing in the specific period of the second period (t4) after the attenuation start command and the laser oscillator starts to attenuate the laser pulse. The laser processing method as described in item 3 of the scope of patent application, wherein in the above first step, the above metal layer is mainly processed on the substrate where the metal layer is laminated on the resin layer, and in the above second step, it is mainly used in The resin layer is processed. The laser processing method according to item 3 or 4 of the scope of patent application, wherein during the second period, the processing is divided into a plurality of times.