WO2018180417A1

WO2018180417A1 - Scribing method and scribing device

Info

Publication number: WO2018180417A1
Application number: PCT/JP2018/009450
Authority: WO
Inventors: 弘義林; 郁祥中谷
Original assignee: 三星ダイヤモンド工業株式会社
Priority date: 2017-03-31
Filing date: 2018-03-12
Publication date: 2018-10-04
Also published as: KR20190129914A; JP7456604B2; JPWO2018180417A1; TW201841840A; CN110475754B; CN110475754A

Abstract

The purpose of the present invention is to, when forming a scribe line on a glass substrate by laser processing, perform the processing so as to facilitate subsequent separation. The scribing method is a method for scribing a glass substrate G and includes the following steps. A scribe line forming step for forming a scribe line 31 by intermittently performing pulsed internal processing on the glass substrate G in the planar direction using a laser device 3. A break line forming step for forming a break line 33 along the scribe line 31 by intermittently performing pulsed internal processing on the glass substrate G in the planar direction using the laser device 3.

Description

Scribing method and scribing apparatus

The present invention relates to a scribing method and a scribing apparatus, and more particularly, to a method and apparatus for forming a scribe line by intermittently performing internal processing of a glass substrate by a pulse using a laser device in a plane direction.

Laser processing is known as a method for scribing a glass substrate. In laser processing, for example, an infrared picosecond laser is used. In this case, a method of forming a scribe line by forming a plurality of laser filaments by intermittently performing internal processing with a pulse in a plane direction by a laser is known (see, for example, Patent Document 1).
In the technique disclosed in US Pat. No. 6,099,089, the focused laser beam is composed of pulses having energy and pulse duration selected to create a filament in the substrate. A scribe line for cleaving the substrate is formed by the plurality of filaments.

Special table 2013-536081 gazette

When performing scribe line processing by forming a filament by laser processing, a large force is required to separate the glass substrate along the scribe line. For this reason, chipping, chipping, cracking and the like are likely to occur during separation along the scribe line, thereby reducing the yield.

An object of the present invention is to form a scribe line on a glass substrate by laser processing so as to facilitate later separation.

Hereinafter, a plurality of modes will be described as means for solving the problem. These aspects can be arbitrarily combined as necessary.

A scribing method according to an aspect of the present invention is a method of scribing a glass substrate, and includes the following steps.
◎ Scribe line formation process to form scribe lines by intermittently processing the glass substrate by pulses using a laser device in the plane direction ◎ After the scribe line formation process, the inside of the glass substrate by pulses using a laser device Break line forming step of forming a break line along the scribe line by intermittently performing processing in the plane direction. In this method, when the break line is formed, inside the glass substrate, the processed portion The structure collapses and an impact acts on the scribe line. Due to this impact, a crack is generated or propagates in the scribe line. As a result, the scribe line can be easily separated.

In the break line forming step, the break line may be formed at a position different from the scribe line in plan view.
In this method, by setting so that the collapse of the structure does not reach the scribe line, the impact on the scribe line can be sufficiently increased.

The break line may be formed substantially parallel to the scribe line.
In this method, it is possible to apply an impact to the scribe line as a whole.

The condensing state may be different between the scribe line forming step and the break line forming step.
In this method, the break line can be formed in a light-collecting state that can give a sufficient impact to the scribe line in the break line forming step.

In the scribe line forming step and the break line forming step, the light collection state may be changed by lens operation.
In this method, since the scribe line and the break line can be processed with one laser device, the manufacturing cost is reduced.

In the scribe line forming step and the break line forming step, the light collection state may be changed by spatial light modulation.
In this method, since the scribe line and the break line can be processed with one laser device, the manufacturing cost is reduced.

A scribing apparatus according to another aspect of the present invention includes a laser apparatus and a control unit that causes the laser apparatus to execute the scribing method.

In the scribe processing method and the scribe processing apparatus according to the present invention, when a scribe line is formed on a glass substrate by laser processing, it can be processed so as to facilitate later separation.

The schematic diagram of the laser processing apparatus of 1st Embodiment of this invention. The top view of the glass substrate of 1st Embodiment. The typical sectional view of a glass substrate. The top view of the glass substrate for demonstrating the state of pulse processing. The typical top view of the glass substrate in a scribe line formation process. The typical sectional view of the glass substrate in a break line formation process. Cross-sectional photograph along the scribe line of the reference example. Sectional photograph along the scribe line of the comparative example. The cross-sectional photograph along the scribe line of the Example. The cross-sectional photograph along the scribe line of the Example. Sectional drawing along the scribe line of an Example. The schematic diagram of the laser processing apparatus of 2nd Embodiment.

1. First Embodiment (1) Overall Configuration FIG. 1 shows an overall configuration of a laser processing apparatus 1 for cutting a glass substrate according to an embodiment of the present invention. FIG. 1 is a schematic diagram of a laser processing apparatus according to a first embodiment of the present invention.
The laser processing apparatus 1 is an apparatus for fully cutting the glass substrate G.
The glass substrate G is soda glass and has a thickness of, for example, 1.8 mm and is in a range of 1.1 to 3 mm.

The laser processing apparatus 1 includes a laser apparatus 3. The laser device 3 includes a laser oscillator 15 for irradiating the glass substrate G with laser light, and a laser control unit 17. The laser oscillator 15 is, for example, a picosecond laser having a wavelength of 340 to 1100 nm. The laser control unit 17 can control the driving of the laser oscillator 15 and the laser power.
The laser device 3 includes a transmission optical system 5 that transmits laser light to a mechanical drive system described later. The transmission optical system 5 includes, for example, a condenser lens 19, a plurality of mirrors (not shown), a prism (not shown), and the like.
The laser processing apparatus 1 has a drive mechanism 11 that changes the condensing angle of laser light by moving the position of the lens in the optical axis direction.

The laser processing apparatus 1 has a processing table 7 on which a glass substrate G is placed. The processing table 7 is moved by the table driving unit 13. The table driving unit 13 has a moving device (not shown) that moves the processing table 7 in the horizontal direction with respect to the bed (not shown). The moving device is a known mechanism having a guide rail, a motor, and the like.

The laser processing apparatus 1 includes a control unit 9. The control unit 9 includes a processor (for example, CPU), a storage device (for example, ROM, RAM, HDD, SSD, etc.) and various interfaces (for example, an A / D converter, a D / A converter, a communication interface, etc.). It is a computer system. The control unit 9 performs various control operations by executing a program stored in the storage unit (corresponding to a part or all of the storage area of the storage device).
The control unit 9 may be composed of a single processor, but may be composed of a plurality of independent processors for each control.

The control unit 9 can control the laser control unit 17. The control unit 9 can control the drive mechanism 11. The control unit 9 can control the table driving unit 13.

The control unit 9 is connected to a sensor (not shown) for detecting the size, shape and position of the glass substrate G, sensors and switches for detecting the state of each device, and an information input device.

(2) Scribing Method A scribing method by the laser processing apparatus 1 will be described with reference to FIGS. FIG. 2 is a plan view of the glass substrate of the first embodiment. FIG. 3 is a schematic cross-sectional view of a glass substrate. FIG. 4 is a plan view of a glass substrate for explaining the state of pulse processing. FIG. 5 is a schematic plan view of the glass substrate in the scribe line forming step. FIG. 6 is a schematic cross-sectional view of the glass substrate in the break line forming step.

(2-1) General Description The scribing method includes the following steps.
A scribe line forming step for forming the scribe line 31 by intermittently performing internal processing of the glass substrate G by the pulse L1 using the laser device 3 in the plane direction (particularly, refer to FIGS. 3 to 5).
After the scribe line formation step, the break line formation step (forms the break line 33 along the scribe line 31 by intermittently performing internal processing of the glass substrate G with the pulse L2 using the laser device 3 in the plane direction) In particular, see FIGS. 3-4 and FIG.

In the scribe line forming step, a processing trace extending along the optical axis is formed inside the glass substrate G in the laser irradiation portion. The processing trace extends between the surfaces of the glass substrate G.
In the break line forming step, a partial processing mark is formed inside the glass substrate G in the laser irradiation portion.
In this method, when the break line 33 is formed, the structure of the processed part is collapsed inside the glass substrate G, and an impact acts on the scribe line 31. Due to this impact, the scribe line 31 is cracked or developed. As a result, the scribe line 31 can be easily separated.

(2-2) Detailed Description In FIG. 2, in the glass substrate G, the scribe line 31 is formed in an annular shape, and the break line 33 is formed in an annular shape outside the scribe line 31. However, the break line may be formed inside the scribe line. Further, the scribe line and the break line may have a shape other than the annular shape.

As shown in FIG. 4, the pitch D1 of the pulse irradiation position S1 constituting the scribe line 31 is in the range of 1 to 6 μm. Further, the pitch D2 of the pulse irradiation position S2 constituting the break line 33 is shorter than the pitch D1. Specifically, the pitch D2 is in the range of 0.5 to 3 μm.
Specifically, in the break line formation step, the break line 33 is formed at a position different from the scribe line 31 in plan view. Therefore, by setting so that the collapse of the structure does not reach the scribe line 31, the impact on the scribe line 31 can be sufficiently increased by forming the break line 33.

More specifically, the break line 33 is formed substantially parallel to the scribe line 31. Therefore, it is possible to give an impact to the scribe line 31 as a whole by forming the break line. However, a part or all of them may not necessarily be parallel. Moreover, the break line does not need to correspond to all of the scribe lines, and may be formed corresponding to only the necessary portions of the scribe lines.
The reason why the scribe line 31 can be easily separated by processing the break line 33 is as follows. That is, when the break line 33 is formed beside the scribe line 31, the structure of the processed part is collapsed and an impact is applied to the scribe part inside the glass substrate G. The impact causes a crack in the scribe portion, and the scribe line 31 can be easily separated.

A distance D3 between the scribe line 31 and the break line 33 is, for example, 45 μm. The distance D3 is preferably in the range of 5 to 70 μm, more preferably 30 to 60 μm. The distances D3 may not all be the same, that is, break lines may be formed at a plurality of different distance positions with respect to the scribe line.
If the distance is too short, the range to which the impact is applied becomes narrow, and the collapse of the structure reaches the scribe line 31, so that a part of the scribe is collapsed and the impact applied to the scribe line 31 is reduced. Therefore, the separation of the scribe line 31 becomes hard.
If the distance is too long, the range of impact is too wide and the impact applied to the scribe line 31 is reduced.

More specifically, the condensing state is different between the scribe line forming step and the break line forming step. As a result, the break line 33 can be formed in a condensing state that can give a sufficient impact to the scribe line 31 in the break line forming step.
For example, the processing conditions of the scribe line 31 are as follows.
1) Pulse energy: 400 μJ (preferably 200 μJ or more)
2) Processing pitch: 4 μm (preferably in the range of 1 to 6 μm)
In this case, the beam waist of the pulse L1 is inside the glass substrate G. As a result, a processing mark extending from the upper surface to the lower surface of the glass substrate G is formed.

The processing conditions of the break line 33 are as follows.
1) Pulse energy: 150 μJ (preferably 100 μJ or more)
2) Processing pitch: 1 μm (preferably in the range of 0.5 to 3 μm)
In this case, the focal point of the pulse L2 is in the middle in the thickness direction of the glass substrate G, and compared with the processing conditions of the scribe line 31, the pulse energy is small and the condensing angle is large. As a result, a partial processing mark is formed in the middle of the glass substrate G in the thickness direction.

In order to change the converging angle, the condensing state is changed by lens operation by the drive mechanism 11 in the scribe line forming step and the break line forming step. Therefore, since the scribe line 31 and the break line 33 can be processed by one laser device 3, the manufacturing cost is reduced.

(3) Examples A plurality of experimental examples will be described with reference to FIGS. FIG. 7 is a cross-sectional photograph taken along the scribe line of the reference example. 8 and 11 are cross-sectional views along the scribe line of the comparative example. 9 to 11 are cross-sectional photographs taken along the scribe line of the example.
FIG. 7 shows a reference example, in which only a scribe line is formed. That is, the break line is not formed, and therefore, the processing trace resulting from the break line is not seen.
FIG. 8 shows a comparative example, in which the distance D3 is 0 μm. In this case, the collapse of the structure has reached the scribe line, and a part of the scribe line has collapsed. As a result, it is difficult to divide the scribe line.

FIG. 9 shows the first embodiment, and the distance D3 is 35 μm. A processing mark generated by the break line formation appears on the cut surface. The plurality of processing marks extend long in the vertical direction.
FIG. 10 shows a second embodiment, in which the distance D3 is 45 μm. A processing mark generated by the break line formation appears on the cut surface. The plurality of processing marks are shorter in the vertical direction than in the first embodiment.
FIG. 11 shows a third embodiment, and the distance D3 is 50 μm. In this case, the processing trace generated by the break line formation does not appear on the cut surface.

2. Second Embodiment In the scribe line forming step and the break line forming step, the light collection state may be changed by spatial light modulation.
Such an embodiment will be described with reference to FIG. FIG. 12 is a schematic diagram of a laser processing apparatus according to the second embodiment.

The laser processing apparatus 1 </ b> A has a spatial light modulator 21 that modulates the laser light emitted from the laser apparatus 3. The spatial light modulator 21 is, for example, a reflection type, and may be a reflection type liquid crystal (LCOS: Liquid Crystal on Silicon) spatial light modulator (SLM: Spatial Light Modulator). The spatial light modulator 21 modulates laser light incident from the horizontal direction and reflects it downward.

The laser processing apparatus 1 </ b> A has a drive unit 23. The drive unit 23 applies a predetermined voltage to each pixel electrode in the spatial light modulator 21 to display a predetermined modulation pattern on the liquid crystal layer, thereby causing the spatial light modulator 21 to modulate the laser light as desired. Here, the modulation pattern displayed on the liquid crystal layer includes, for example, the position where the processing mark is to be formed, the wavelength of the laser beam to be irradiated, the material of the processing target, and the refractive index of the transmission optical system 5 and the processing target. Is derived in advance based on the above and stored in the control unit 9.
In this method, since the scribe line and the break line can be processed with one laser device 3, the manufacturing cost is reduced.

3. Third Embodiment As a modification of the first embodiment, a third embodiment in which the breakline pitch is changed will be described. Other conditions are the same as in the first embodiment.
In this embodiment, the pitch D1 of the pulse irradiation position S1 constituting the scribe line 31 is in the range of 1 to 6 μm. And unlike 1st Embodiment, the pitch D2 of the pulse irradiation position S2 which comprises the break line 33 is the same grade as the pitch D1. Specifically, the pitch D2 is in the range of 1 to 6 μm.

In this embodiment, the distance D3 between the scribe line 31 and the break line 33 is in the range of 5 to 300 μm. The above range is preferably, for example, 30 to 60 μm or 100 to 190 μm. The distances D3 may not all be the same, that is, break lines may be formed at a plurality of different distance positions with respect to the scribe line.
For example, the processing conditions of the scribe line 31 are as follows.
1) Pulse energy: 667 μJ
2) Processing pitch: 4 μm (processing speed is 600 mm / s, repetition frequency is 150 kHz)
In this case, the beam waist of the pulse L1 is inside the glass substrate G. As a result, a processing mark extending from the upper surface to the lower surface of the glass substrate G is formed.

The processing conditions of the break line 33 are as follows.
1) Pulse energy: 667200 μJ
2) Processing pitch: 4 μm (processing speed is 600 mm / s, repetition frequency is 150 kHz)
In this case, the focal point of the pulse L2 is in the middle in the thickness direction of the glass substrate G, and compared with the processing conditions of the scribe line 31, the pulse energy is small and the condensing angle is large. As a result, a partial processing mark is formed in the middle of the glass substrate G in the thickness direction.
In the above embodiment, the same effect as that of the first embodiment can be obtained.

4). Other Embodiments Although one embodiment of the present invention has been described above, the present invention is not limited to the above embodiment, and various modifications can be made without departing from the scope of the invention. In particular, a plurality of embodiments and modifications described in this specification can be arbitrarily combined as necessary.

In the first embodiment and the second embodiment described above, the scribe line and the break line are formed using the common laser device 3, but a dedicated laser device may be used. In this case, a picosecond laser can be used for forming a scribe line, and a picosecond or nanosecond laser can be used for forming a break line.
In the above embodiment, the scribe line and the break line are formed by irradiating the pulse laser. However, instead of this, the pulse laser group oscillated in the burst mode may be irradiated.

The present invention can be widely applied to a method and an apparatus for forming a scribe line by intermittently performing internal processing of a glass substrate by a pulse using a laser device in a plane direction.

1: Laser processing device 3: Laser device 5: Transmission optical system 7: Processing table 9: Control unit 11: Drive mechanism 13: Table drive unit 15: Laser oscillator 17: Laser control unit 19: Condensing lens 21: Spatial light modulation Device 23: Drive unit 31: Scribe line 33: Break line

Claims

A method of scribing a glass substrate,
A scribe line forming step for forming a scribe line by intermittently performing internal processing of a glass substrate by a pulse using a laser device in a plane direction;
After the scribe line formation step, the break line formation step of forming a break line along the scribe line by intermittently performing internal processing of the glass substrate by a pulse using the laser device in the plane direction;
A scribing method comprising
The scribing method according to claim 1, wherein in the break line forming step, the break line is formed at a position different from the scribe line in plan view.
The scribing method according to claim 2, wherein the break line is formed substantially parallel to the scribe line.
The scribing method according to any one of claims 1 to 3, wherein a condensing state is different between the scribe line forming step and the break line forming step.
The scribing method according to claim 4, wherein the condensing state is changed by lens operation in the scribe line forming step and the break line forming step.
The scribing method according to claim 4, wherein the condensing state is changed by spatial light modulation in the scribe line forming step and the break line forming step.
A laser device;
A controller that causes the laser apparatus to execute the scribing method according to any one of claims 1 to 6,
A scribing machine equipped with