TWI491573B - Method for scribing a glass board and a processing device - Google Patents

Description

Glass substrate marking method and processing device

The present invention relates to a method of scribing a glass substrate, and more particularly to a method of scribing a glass substrate along a scribe line of a glass having a reinforcing layer having a compressive stress on the surface.

A method for forming a scribe groove by dividing a glass substrate is a method of forming a scribe groove by using laser light. At this time, the laser light is irradiated along a predetermined line of the scribe line, and one of the substrates is partially dissolved and evaporated to form a scribe groove. However, in this method, a part of the substrate which is dissolved and evaporated adheres to the surface of the substrate, and there is a case where the quality is deteriorated. Further, the crack formed by the dissolved and evaporated portion is a cause of a decrease in the strength of the end face of the substrate.

Therefore, there is a method shown in Patent Document 1 or 2 for other methods of forming the scribe groove. Here, an initial crack is formed in a place where the starting line of the scribe line of the glass substrate is formed, and the initial crack is irradiated with laser light. Thereby, thermal stress is generated in the laser irradiation portion, and the crack progresses to form the scribe groove.

Further, in the method of irradiating the laser light to form the scribe groove, the crack of the scribe groove in the peripheral portion of the glass substrate tends to become deep. In this state, when the glass substrate is divided along the scribe groove, there is a problem that the quality of the cross-section is lowered, or the scribe groove is not formed straight.

Therefore, in Patent Document 3, there is disclosed a predetermined line in the scribe line. The terminal portion forms a laser scribing method in which a region in which the scribe groove is not formed is formed. According to this method, the sectional quality after the break in the end portion of the glass substrate can be improved without complicated control.

(previous technical literature) (Patent Literature)

Patent Document 1: Japanese Patent Laid-Open No. 3-489

Patent Document 2: Japanese Patent Laid-Open Publication No. 9-1370

Patent Document 3: Japanese Re-issued Patent No. WO2007/094348

However, in recent FPD (flat panel display) companies, since the strength of the end face of the substrate is emphasized, a chemically strengthened glass having a reinforcing layer formed on the surface thereof is mainly used as the glass substrate. The chemically strengthened glass has a layer (strengthening layer) which is subjected to compressive stress on the surface by ion exchange treatment, and has tensile stress inside. Recently, this chemically strengthened glass is used for a cover glass such as a touch panel which particularly requires end face strength.

The inventor of the present invention discovered through experiments that when the scribed groove is formed in the tempered glass by the laser scribing method, especially the surface-strength tempered glass, the deep crack will mainly be engraved. The terminal portion of the scribe groove is naturally separated along the progress of the scribe groove. Here, the natural breaking is a phenomenon in which the glass substrate is broken along the scribe groove without forming the dicing groove after the scribe line is formed.

The natural breaking may be caused by the crack in the groove of the scribe groove becoming deeper at the peripheral portion of the glass substrate, and the deep crack is generated along the scribe groove. By. Further, the phenomenon that the crack of the scribe groove becomes deeper at the peripheral portion of the glass substrate may be the following reason.

At the end portion of the glass substrate on which the scribe groove is formed, since the end faces are not restrained, both sides of the scribe groove are opened.

At the end portion of the glass substrate on which the scribe groove is formed, heat is not stopped at the end portion, and heat is stagnated at the end portion.

When natural breaks occur due to the above reasons, the processing of the subsequent steps becomes difficult.

Therefore, in order to prevent the scribed groove from being formed on the peripheral portion of the glass substrate, it is considered that the aluminum strip is attached to the end portion of the predetermined line of the scribe line to shield the laser light. However, this method is not practical from the viewpoint of productivity.

Further, by controlling the irradiation of the laser light, the heat treatment and the cooling treatment are not performed on the peripheral portion of the glass substrate, and the scribe groove does not reach the end of the predetermined line of the scribe line. However, this method is difficult to block the scribe groove at the desired position and is not stable.

An object of the present invention is to easily and stably form a desired scribe groove for a glass having a reinforcing layer on its surface to prevent natural breakage.

The scribe line method for a glass substrate according to the first aspect of the invention is a scribe line method for dicing a glass having a reinforcing layer having a compressive stress on a surface along a predetermined line of scribe lines, and has the following steps.

In the first step, the glass is placed on a pedestal having a plurality of suction holes for holding the substrate, and the glass end portion on the terminal side of the predetermined line of the scribe line of the glass is sucked by a stronger suction pressure than the central portion. With.

The second step: forming an initial crack on the surface of the glass.

Step 3: The laser light is irradiated onto the surface of the glass and heated, and the heated region is cooled, and the crack is progressed along the predetermined line of the scribe line to form a scribe groove.

Here, first, the pedestal is placed with the glass to be processed. A plurality of holes for suction are provided in the pedestal, and the glass is sucked through the suction holes to be held at a predetermined position of the pedestal. At this time, the glass end portion on the terminal side of the predetermined line of the scribe line is attracted and held with a stronger force than the other regions. Further, after the initial crack is formed, the laser light is irradiated onto the surface of the glass and heated, and the heated region is cooled. By this heating and cooling treatment, the initial cracking progresses along the predetermined line of the scribe line, and the scribe groove is formed.

In this method, the glass end portion on the terminal side of the predetermined line of the score line is held at the pedestal with a stronger suction force. Therefore, the glass end portion is not easily deformed when subjected to heating and cooling treatment. Therefore, the crack does not easily crack at the end of the glass, but the formation of deep cracks can be suppressed, and natural breakage can be avoided. Further, it is not necessary to attach a troublesome work such as an aluminum tape, and it is possible to stably prevent the formation of the scribe groove at a desired position.

In the scribing method for the glass substrate according to the second aspect of the invention, in the first step, in the first step, the glass is scribed at the beginning of the predetermined line at a stronger suction pressure than the central portion. The end of the glass on the side is sucked.

For example, when the groove of the initial crack is deep, in the step of forming the scribe groove (third step), the deep crack is from the initial crack to the direction opposite to the scanning direction of heating and cooling, that is, Progress towards the end of the glass, and there is a natural break.

Therefore, in the second aspect of the invention, the glass end portion on the start end side of the predetermined line of the score line is held by the strong suction force. Thereby, deformation at the end portion of the glass at the time of formation of the scribe groove is suppressed, and the progress of the crack toward the start end side of the predetermined line of the scribe line can be suppressed. Therefore, natural breaks can be avoided.

In the scribing method for the glass substrate according to the third aspect of the invention, in the third step, the scribe line is formed along a predetermined line of a plurality of scribe lines orthogonal to each other. Further, in the first step, the entire outer peripheral end portion of the glass is sucked by a stronger suction pressure than the other regions.

Here, when the cross scribe line is formed, it is possible to suppress the formation of deep cracks at the end portions of the glass in the same manner as described above, and it is possible to avoid natural breakage.

The apparatus for processing a glass substrate according to the fourth aspect of the invention is a device for dicing a glass having a reinforcing layer having a compressive stress on a surface along a predetermined line of a scribe line, and has a pedestal, an illuminating unit, and a cooling unit. , moving means and suction pressure control unit. The platform has a plurality of suction holes and sucks and holds the glass placed on the surface. The illuminating unit radiates the laser beam to the glass. The cooling portion is cooled by the region heated by the irradiation portion. The moving means moves the irradiation portion and the cooling portion relative to each other along a predetermined line which is set at the time of the glass. The suction pressure control unit controls the suction pressure of the seat so that the end portion on the terminal side of the predetermined line of the at least scribe line of the glass is stronger than the central portion.

As described above, the present invention is directed to a glass having a reinforcing layer having a compressive stress on the surface, and it is easy and stable to prevent the crack from progressing in front of the end portion of the predetermined line of the scribe line. Therefore, it is possible to prevent the glass from being naturally broken at the time point when the scribe groove is formed in the glass.

[device configuration]

Fig. 1 is a schematic configuration diagram of an apparatus for carrying out a scribing method according to an embodiment of the present invention. Fig. 1 is a schematic configuration diagram of an apparatus for carrying out a scribing method according to an embodiment of the present invention. The scribe line device 1 is a device that divides, for example, a main glass substrate into a plurality of unit substrates used in an FPD (Flat Panel Display). The glass substrate used here is mainly used for chemically strengthened glass in which a reinforcing layer is formed on the surface. As described above, the chemically strengthened glass has a strengthening layer which has a compressive stress on the surface by ion exchange treatment.

The scribe line apparatus 1 includes a pedestal 2 on which a glass substrate G is placed, a cutting wheel 3, a laser irradiation unit 4, a cooling unit 5, a drive mechanism 6, two suction pumps 7a and 7b, and a control unit 8.

A plurality of through holes 10 whose upper portion is liberated on the surface of the pedestal are formed in the pedestal 2. The through hole 10a formed in the through hole 10 at a position corresponding to the outer peripheral end portion of the glass substrate G is connected to the first suction pump 7a through the first passage 11 indicated by the solid line. Further, the plurality of through holes 10b other than the through hole 10a are connected to the second suction pump 7b through the second passage 12 indicated by the one-point chain line.

The cutter wheel 3 is a tool for forming a crack as a starting point of the score line at the end portion of the glass substrate G. The cutting wheel 3 mainly has a holder and a scribing wheel that supports the holder.

The laser irradiation unit 4 has a laser oscillator (for example, a CO ₂ laser) that irradiates a laser beam, and the laser beam is irradiated onto the glass substrate G as a beam spot through an optical system. Further, the cooling unit 5 forms a cooling point by a refrigerant (for example, water, air, helium, or the like) supplied from a refrigerant source (not shown) through a nozzle.

The drive mechanism 6 is a mechanism that moves the cutting wheel 3, the laser irradiation unit 4, and the cooling unit 5 along the rail 14. By the drive mechanism 6, the cutting wheel 3, the laser irradiation unit 4, and the cooling unit 5 are moved along a predetermined line which is set on the glass substrate G.

The control unit 8 controls the cutting wheel 3, the laser irradiation unit 4, the cooling unit 5, the drive mechanism 6, and the two suction pumps 7a and 7b. Specifically, the control unit 8 controls the pressing force of the cutting wheel 3 on the glass substrate G, the laser output, the amount of injection of the refrigerant, the driving speed (scanning speed), and the number of rotations of the suction pumps 7a and 7b (sucking Pressure).

[Relationship between substrate suction pressure and scribe line]

The following shows the results of the scribing when the laser output and the scanning speed are changed and the suction pressure is changed under the respective conditions. The results of the respective experimental examples are shown in Table 1.

<Experimental Example 1>

The suction pressure (kPa) of the glass substrate G to the pedestal 2: 5, 10, 20

Laser output: 140W

Scanning speed: 190mm/s

In the first test example, although the scribe line can be scored at a low suction pressure of 5 kPa (indicated by ○ in Table 1), it cannot be scored at a high suction pressure of 10 and 20 kPa (in Table 1 × indicates).

<Experimental Example 2>

The suction pressure (kPa) of the glass substrate G to the pedestal 2: 5, 10, 20

Laser output: 160W

Scanning speed: 230mm/s

In the experimental example 2, although the scribe line was drawn at a low suction pressure of 5 and 10 kPa, the scribe line could not be scribed when the suction pressure was 20 kPa.

<Experimental Example 3>

The suction pressure (kPa) of the glass substrate G to the pedestal 2: 5, 10, 20

Laser output: 170W

Scanning speed: 250mm/s

In Experimental Example 3, although the scoring was performed at a low suction pressure of 5 and 10 kPa, the scribing could not be performed at a suction pressure of 20 kPa.

<Experimental Example 4>

The suction pressure (kPa) of the glass substrate G to the pedestal 2: 5, 10, 20

Laser output: 180W

Scanning speed: 260mm/s

In the experimental example 4, although the low suction pressure is 5 and 10 kPa, the score line can be scribed, but the scribe line cannot be scored when the suction pressure is 20 kPa.

From the above experimental examples, it is known that when the suction pressure is raised, that is, the suction force is increased, the deformation of the glass substrate is suppressed when the scribe groove is formed, and the progress of the crack is stopped.

[scribe line method]

According to the above findings, in the present embodiment, the scribe groove is formed by the following scribing method.

First, the glass substrate G to be processed is placed on the pedestal 2. Then, the first suction pump 7a and the second suction pump 7b are driven, and the glass substrate G is sucked onto the pedestal 2. At this time, each suction pump is controlled by the control unit 8. The number of rotations of 7a and 7b is controlled so that the suction pressure of the first suction pump 7a is 20 kPa or more, and the suction pressure of the second suction pump 7b is controlled to 10 kPa or less.

Next, the initial crack which is the starting point of the score line is formed on the end portion of the glass substrate G by the cutter wheel 3.

Then, the laser beam is irradiated from the laser irradiation unit 4 to the glass substrate G. This laser beam is irradiated onto the glass substrate G as a beam spot. Then, the laser beam emitted from the laser irradiation unit 4 is scanned along a predetermined line of the scribe line. The glass substrate G is heated by the beam spot to a temperature lower than the softening point of the glass substrate G. In addition, the cooling point follows the direction of movement of the beam spot.

As described above, although compressive stress is generated in the vicinity of the beam spot heated by the irradiation of the laser beam, the cooling point is formed by the ejection of the refrigerant, so that compressive stress effective for the vertical crack is generated. . By the compressive stress, a vertical crack along a predetermined line of the scribe line is formed with the initial crack formed at the end portion of the glass substrate G as a starting point to form a desired scribe groove.

Here, in the step of forming the scribed groove, the beginning end portion and the end portion of the predetermined line of the scribe line, that is, the end portion of the glass substrate G are held by the strong suction pressure (suction force). Therefore, deformation of the glass substrate G due to heating and cooling treatment can be suppressed, and progress of cracks can be suppressed. Therefore, it is possible to suppress formation of deep cracks at the end portions of the glass substrate G, and it is possible to prevent the substrate from being naturally broken.

〔feature〕

In the present embodiment, a strong urging force holds the glass substrate on the pedestal to suppress deformation during processing, and therefore, it can be suppressed at the glass substrate end. The part forms deep cracks and avoids the natural breaking of the substrate.

Further, in the means for stopping the crack growth at the end portion of the glass substrate, the suction pressure of the substrate to the pedestal is achieved by the control, so that the natural division of the substrate can be avoided in a simple manner.

[Other Embodiments]

The present invention is not limited to the embodiments described above, and various modifications and changes can be made without departing from the scope of the invention.

(a) In the above embodiment, the glass substrate is scribed to both the end portion of the start side and the end portion of the end portion of the predetermined line with a strong urging force, but it can be kept only with a strong force. The end portion of the terminal portion of the predetermined line is scribed. Further, when the end portion on the start side is held by a strong urging force, the progress of the initial crack is suppressed, and the scribe groove is not formed, so that the end portion of the start side is held at the end than the terminal side. The Ministry is weaker and stronger than the Central Department.

(b) In the above embodiment, the pedestal is fixed and the laser irradiation unit or the like is moved. However, the laser irradiation unit or the like may be fixed and the pedestal may be moved.

(c) In the above embodiment, the cutting wheel for forming the initial crack is provided in the same apparatus as the laser irradiation unit or the like, but the cutting wheel may be provided in a device different from the laser irradiation unit or the like. At this time, first, after the initial crack is formed, the glass substrate is sucked on the pedestal. That is, the order of the initial crack forming step (second step) and the step of placing the glass substrate on the pedestal (first step) is the reverse of the above embodiment.

(d) In the above embodiment, the cutting wheel for forming the initial crack is used, but the initial crack may be formed by laser processing such as laser ablation or modification. At this time, set a laser with a UV laser or a green laser as a light source. The irradiation mechanism is used as an initial crack formation.

1‧‧‧ marking device

2‧‧‧ pedestal

3‧‧‧Cutting wheel

4‧‧‧Laser illumination department

5‧‧‧ Cooling Department

6‧‧‧Drive mechanism

7a, 7b‧‧‧ suction pump

8‧‧‧Control Department

10, 10a, 10b‧‧‧ through holes

11‧‧‧1st pathway

12‧‧‧2nd pathway

14‧‧‧ Track

G‧‧‧glass substrate

Fig. 1 is a schematic configuration diagram of an apparatus for carrying out a scribing method according to an embodiment of the present invention.

1‧‧‧ marking device

2‧‧‧ pedestal

3‧‧‧Cutting wheel

4‧‧‧Laser illumination department

5‧‧‧ Cooling Department

6‧‧‧Drive mechanism

7a, 7b‧‧‧ suction pump

8‧‧‧Control Department

10, 10a, 10b‧‧‧ through holes

11‧‧‧1st pathway

12‧‧‧2nd pathway

14‧‧‧ Track

G‧‧‧glass substrate

Claims (4)

A method for scribing a glass substrate, which is a method for scribing a glass substrate having a reinforcing layer having a compressive stress on a surface along a predetermined line of a scribe line, which has the following steps: Step 1 The glass is placed on a pedestal having a plurality of suction holes for holding the substrate, and the glass end portion on the terminal side of the predetermined line of the scribe line of the glass is sucked by a stronger suction pressure than the central portion; In the second step, an initial crack is formed on the surface of the glass; and in the third step, the laser light is irradiated on the surface of the glass and heated, and the heated region is cooled, and the crack is progressed along the predetermined line of the scribe line. And forming a scribe groove. The method for scribing a glass substrate according to claim 1, wherein in the first step, the glass is scribed at a starting end side of a predetermined line with a stronger suction pressure than the central portion. The ends of the glass on both sides of the terminal side are sucked. The scribe line method for a glass substrate according to claim 1, wherein in the third step, the scribe line is formed along a predetermined line of a plurality of scribe lines orthogonal to each other, and the In the first step, the entire outer peripheral end of the glass is sucked by a stronger suction pressure than the other regions. A processing device for a glass substrate, which is a device for dicing a glass having a reinforcing layer having a compressive stress on a surface along a predetermined line of a scribe line, and has a pedestal having a plurality of absorbing holes And suck and keep placed on a glass on the surface; the illuminating portion radiates the laser beam to the glass; the cooling portion cools the region heated by the illuminating portion; and the moving means is scribed along a predetermined line set at the glass The illuminating unit and the cooling unit are relatively moved, and the absorbing pressure control unit controls the squeezing pressure of the seat so that the end portion on the terminal side of the predetermined line of the scribe line of the glass is stronger than the center portion.