KR101396989B1

KR101396989B1 - Scribe method for glass substrate

Info

Publication number: KR101396989B1
Application number: KR1020120088561A
Authority: KR
Inventors: 유 항 수; 타케시 이케다; 코지 야마모토
Original assignee: 미쓰보시 다이야몬도 고교 가부시키가이샤
Priority date: 2011-08-24
Filing date: 2012-08-13
Publication date: 2014-05-21
Also published as: TW201313636A; KR20130023081A; CN102951837A

Abstract

[PROBLEMS] A desired scribe groove is easily and stably formed on a surface-reinforced glass to prevent natural division.
[MEANS FOR SOLVING PROBLEMS] This scribing method is a scribing method for tempered glass having a reinforcing layer having a compressive stress on its surface, and includes a crack regulating groove forming step and a scribing groove forming step. In the crack regulating groove forming step, a groove for regulating cracks having a predetermined width is formed on the surface of the glass in a direction intersecting the planned scribing line at the terminal end of the line to be scribed. In the scribe groove forming step, the surface of the glass is irradiated with laser light and heated, and the heated region is cooled to advance the crack along the planned scribing line to form the scribe groove.

Description

[0001] SCRIBE METHOD FOR GLASS SUBSTRATE [0002]

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

As a method of forming a scribe groove for dividing a glass substrate, there is a method of forming a scribe groove using laser light. In this case, laser light is irradiated along the planned scribing line, and a portion of the substrate is dissolved and evaporated, and a scribe groove is formed. However, in this method, a part of the dissolved and evaporated substrate adheres to the surface of the substrate, which may lead to deterioration in quality. In addition, the flaws formed in the melted and evaporated portions cause a decrease in the strength of the end face of the substrate.

As another method of forming the scribe groove, there is a method as shown in Patent Document 1 or 2. In this case, an initial crack is formed at a position that becomes a starting point of the scribe groove of the glass substrate, and the laser beam is irradiated to this initial crack. As a result, a thermal stress is generated in the laser-irradiated portion, and cracks develop to form scribe grooves.

Further, in the method of forming the scribe groove by irradiating the laser beam, the crack of the scribe groove tends to deepen in the peripheral edge portion of the glass substrate. In this state, when the glass substrate is divided along the scribe grooves, there arises a problem of deteriorating the quality of the sectional plane and a problem that the scribe grooves are not formed straight.

Thus, Patent Document 3 shows a laser scribing method in which a region where a scribe groove is not formed is formed at a terminal end of a line to be scribed. According to this method, it is described that the quality of the cross section after the glass substrate is divided at the end portion can be improved without complicated control.

Patent Document 1: JP-A-3-489 Patent Document 2: JP-A-9-1370 Patent Document 3: Japanese Published Patent Application No. WO2007 / 094348

However, in the FPD (flat panel display) industry in recent years, since the strength of the end face of the substrate is important, a chemically tempered glass having a reinforcing layer formed on its surface is mainly used as a glass substrate. This chemical tempered glass has a layer (reinforcing layer) having a surface subjected to compressive stress by ion exchange treatment, and tensile stress is present in the inside. Such a chemically tempered glass is recently used in a cover glass such as a touch panel in which end surface strength is particularly required.

When the scribe groove is formed on a tempered glass having a particularly high surface strength and developed by the laser scribing method among the above tempered glass, the inventor has found that a deep crack develops mainly along the scribe groove from the end portion of the scribe groove , And it was found by experiments that natural division is possible. Here, the natural division refers to a phenomenon in which the glass substrate is divided along the scribe groove without performing the dividing step after the scribe groove is formed.

It can be considered that the natural division is caused by the deepening of the cracks in the scribe grooves at the periphery of the glass substrate and it can be considered that the deep cracks are generated by advancing along the scribe grooves. The reason why the scribe groove is deepened in the periphery of the glass substrate is considered as follows.

At both end portions of the glass substrate on which the scribe grooves are formed, both sides of the scribe grooves tend to spread because the end faces are not confined.

At the end of the glass substrate on which the scribe groove is formed, there is no place for heat to escape from there, and the end portion is filled with heat.

If natural division occurs due to the above-described causes, it becomes difficult to perform the post-processing.

Thus, it is conceivable to shield the laser light by attaching an aluminum tape to the end portion of the line to be scribed so that the scribe groove is not formed in the peripheral portion of the glass substrate. However, this method is not practical from the viewpoint of productivity.

It is also conceivable to prevent the scribe groove from reaching the end of the line to be scribed by controlling the irradiation of the laser beam so that the peripheral portion of the glass substrate is not heated and cooled. However, in this method, it is difficult to stop the scribe groove at a desired position, and there is no stability.

Furthermore, the inventors of the present invention have found that similar problems arise not only at the end portion of the glass substrate but also at the start end (start end). That is, if an initial crack is formed at the edge or end of the glass substrate which is the start end of the line to be scribed, the initial crack is formed deeply in the process of forming the scribe groove. Then, due to this deep crack, after the scribe groove is formed, the glass substrate is naturally divided without performing the dividing step.

Therefore, it is conceivable to form the initial crack by offsetting from the starting end (the edge of the substrate) to the inside as a countermeasure for avoiding natural division. However, even if such countermeasures are carried out, there is a case where natural division is likewise performed. The phenomenon in this case will be described in more detail. Initially, in the step of forming the scribe groove, in some cases, cracks may advance toward the edge of the glass substrate, as opposed to the scanning direction of laser light, from the initial crack. Then, when cracks propagate from the initial cracks to the edge of the glass substrate, the depth of the cracks in the edge portions of the glass substrate deepens to the entire thickness of the substrate. Due to the deep cracks formed in the edge portions, the glass substrate is naturally divided along the scribe groove. If such a natural division occurs, it becomes difficult to perform post-processing.

Therefore, it is also conceivable to increase the amount of the offset. However, if the amount of the offset is increased, a useless portion (a portion which can not be secured as a product) is increased in the periphery of the glass substrate, and the yield is poor.

An object of the present invention is to form a desired scribe groove easily and stably, particularly on a surface-reinforced glass, to prevent natural division.

A scribing method of a glass substrate according to the first invention is a method of scribing a glass having a reinforcing layer having a compressive stress on its surface and includes a crack regulating groove forming step and a scribing groove forming step. In the crack regulating groove forming step, a groove for regulating cracks having a predetermined width in the direction intersecting the planned scribing line is formed at the end of the line to be scribed on the surface of the glass. In the scribe groove forming step, the surface of the glass is irradiated with laser light and heated, and the heated region is cooled to advance the crack along the planned scribing line to form the scribe groove.

Here, grooves for regulating crack propagation in the direction intersecting the planned scribing line are formed at the end portion of the planned scribing line. Thereafter, the glass surface is irradiated with laser light to be heated, and further the heated region is cooled. By this heating and cooling process, cracks are developed along the planned scribing line, and scribe grooves are formed. The progress of the crack is regulated by the crack-forming groove formed first. Therefore, the scribe groove is not formed at the end portion of the line to be scribed.

By this method, it is possible to prevent deep cracks from being formed at the end portion of the line to be scribed, and natural division can be avoided. Further, complicated operations such as attaching an aluminum tape are unnecessary, and further, the formation of the scribe grooves can be stably stopped at a desired position.

The scribing method of the glass substrate according to the first aspect of the present invention is characterized in that as an earlier step of the scribe groove forming step, an initial crack forming step of removing a part of the strengthening layer to form an initial crack .

Here, a part of the reinforcing layer formed on the surface of the glass is removed by a cutter wheel or the like, and an initial crack is formed. Thereafter, the initial crack is irradiated with laser light to be heated, and further the heated region is cooled. This allows the initial crack to propagate along the planned scribe line. Therefore, a desired scribe groove can be stably formed.

A scribing method of a glass substrate according to a third aspect of the present invention is a scribing method for scribing a glass having a reinforcing layer having a compressive stress on its surface and includes an initial crack forming step, a scribing groove forming step, do. The initial cracking process removes at least a portion of the enhancement layer on the surface of the glass to form an initial crack. In the scribe groove forming step, the surface of the glass is irradiated with laser light and heated, and the heated region is cooled to advance the initial crack along the planned scribing line to form the scribe groove. The crack regulating groove forming step is a step of regulating the initial cracking process in the scribe groove forming process in order to regulate the advance of the initial crack in the direction opposite to the crack progressing direction, A crack restricting groove having a predetermined width in a direction intersecting the direction in which the planned scribing line extends is formed between the initial crack and the edge of the glass substrate on the surface of the glass substrate.

Here, an initial crack is formed in the vicinity of the start end of the line to be scribed. A groove is formed between the initial crack and the edge of the glass substrate so as to restrict cracks from propagating in a direction opposite to the direction in which the planned scribing line extends. Thereafter, the glass surface is irradiated with laser light to be heated, and further the heated region is cooled. By this heating and cooling process, cracks are developed along the planned scribing line, and scribe grooves are formed. At this time, the crack advances toward the end portion of the scribing line, but may also proceed in the reverse direction. However, this crack developing in the reverse direction is stopped by the groove formed between the initial crack and the edge of the glass substrate.

Therefore, it is possible to prevent the initial crack from developing in the reverse direction and forming a deep crack in the glass substrate edge portion. Therefore, the natural division after the scribe groove formation can be suppressed.

In addition, since the formation of cracks from the initial cracks toward the substrate edge can be regulated, the portion that can not be secured as a product between the initial crack and the substrate edge can be reduced and the yield of the product can be improved.

The scribing method of a glass substrate according to a fourth invention is characterized in that in the scribing method of the first or third invention, in the crack regulating groove forming step, the crack regulating groove is formed so as to extend in a direction perpendicular to the planned scribing line do.

Here, since the crack restricting grooves are formed in the direction perpendicular to the planned scribing line, the progress of the crack can be more reliably stopped.

In the scribing method of a glass substrate according to the fifth invention, in the scribing method of the first or third invention, in the crack regulating groove forming step, the crack regulating groove is shallower than the depth of the scribe groove formed in the scribing groove forming step .

Here, when the crack regulating groove is deepened, cracks naturally propagate starting from the crack regulating groove by the tensile stress inside the glass substrate, and the substrate may be separated by this crack.

Thus, in the fifth invention, the crack restricting groove is shallower than the depth of the scribe groove, so that the natural division of the substrate is avoided.

In the scribing method of the glass substrate according to the sixth invention, in the scribing method of the first or third invention, the initial crack formed in the initial crack forming step and the groove formed in the crack regulating groove forming step are both And a space between them.

Here, since the initial cracks and the crack-restricting grooves are formed apart from each other, it is possible to more reliably prevent the initial crack from advancing to the edge of the glass substrate.

As described above, according to the present invention, it is possible to easily and stably stop the advance of cracks in the glass immediately before the end of the planned scribing line with respect to the glass having the reinforcing layer having the compressive stress on the surface thereof. Therefore, it is possible to prevent the natural division of the glass at the time when the scribe groove is formed in the glass.

Further, in the present invention, it is possible to suppress the initial crack from propagating in the reverse direction toward the edge of the glass substrate. Therefore, it is possible to prevent the natural division of the glass at the time when the scribe groove is formed in the glass.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic configuration view of an apparatus for carrying out a scribing method according to a first embodiment of the present invention; FIG.
2 is a schematic structural view of an apparatus for carrying out a scribing method according to a second embodiment of the present invention;
3 is a view showing a state in which a substrate is naturally separated when scribing is performed by a conventional method;
Fig. 4 is a diagram showing the relation between the pressing load and the initial crack for the initial crack formation for tempered glass having a thickness of 0.55 mm and the scribe result. Fig.
5 is an enlarged cross-sectional view of a portion of a tempered glass having an initial crack formed;
6 is a diagram showing the relationship between the pressing load and the initial crack for the initial crack formation for tempered glass having a thickness of 0.7 mm and the scribe result.
7 is a diagram showing the relationship between the pressing load and the initial crack for the initial crack formation for tempered glass having a thickness of 1.1 mm and the scribe result.

[Device Configuration]

BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a diagram showing a schematic configuration of a scribe apparatus for carrying out a method according to an embodiment of the present invention; FIG. The scribe device 1 is, for example, an apparatus for dividing a mother glass substrate into a plurality of unit substrates used in an FPD (flat panel display). The glass substrate used here is mainly a chemically tempered glass having a reinforcing layer formed on its surface. As described above, this chemically tempered glass has a reinforcing layer that imparts compressive stress to the surface by ion exchange treatment.

The scribing apparatus 1 includes an irradiating unit 2 for irradiating the laser beam toward the glass substrate G, a cooling unit 3, and a moving unit (not shown). The cooling section 3 forms a cooling spot CP by injecting a coolant supplied from a coolant source (coolant source), not shown, through the nozzle 4. [ The moving unit relatively moves the nozzles 4 of the irradiation unit 2 and the cooling unit 3 with the glass substrate G along the planned scribing line SL set on the glass substrate G. [

The irradiation unit 2 has a laser oscillator (for example, a CO ₂ laser) for irradiating a laser beam LB and irradiates the laser beam LB onto a glass substrate G through an optical system, ).

Incidentally, although not shown here, an initial crack forming means for forming an initial crack to be a starting point of the scribe is provided at the end of the glass substrate G. As the initial crack forming means, a mechanical tool such as a cutter wheel is used, but it is also possible to form an initial crack by irradiation with a laser beam.

[How to scribe]

- First Embodiment -

First, as shown in Fig. 1, an initial crack TR to be a starting point of a scribe is formed at the end of the glass substrate G by using an initial crack forming means such as a cutter wheel or the like. At this time, the depth of the initial crack TR is set to a depth to the extent that the reinforcing layer formed on the surface of the glass substrate (tempered glass) is peeled off. Specifically, the depth of the initial crack TR is set to 1.0 times or more and 2.0 times or less the thickness of the reinforcing layer.

A plurality of crack regulating grooves S for stopping the crack progressing along the planned scribing line SL are formed at the end portion of the scribing line SL as the previous step or the subsequent step of the initial crack. Each of the plurality of crack restricting grooves S is formed with a predetermined width in a direction orthogonal to the planned scribing line SL. It is preferable that the depth of the crack regulating groove S is shallower than the depth of the scribe groove formed in a later step. The reason is that if the crack regulating groove S is too deep, cracks naturally develop starting from the crack regulating groove S by the tensile stress inside the glass substrate, and the substrate is separated by this crack to be. Further, it is preferable that the depth of the crack regulating groove S is made deeper than the thickness of the reinforcing layer.

In addition, the crack regulating groove S may be one groove perpendicular to all the scribing lines SL. However, it is preferable to form a plurality of grooves locally in order to reduce foreign matter such as dust generated during the formation of the grooves.

Next, the laser beam LB is irradiated to the glass substrate G from the irradiating unit 2. Then, This laser beam LB is irradiated onto the glass substrate G as a beam spot LS. The laser beam LB emitted from the irradiation unit 2 is moved along the planned scribing line SL relative to the glass substrate G. [ The glass substrate G is heated to a temperature lower than the softening point of the glass substrate G by the beam spot LS. Further, the cooling spots CP follow the movement direction of the beam spot LS. It is also conceivable to stop at the groove for crack growth stop in the scanning of the beam spot and the cooling spot. However, in order to facilitate the control of the laser irradiation, it is preferable to perform the scanning to the end of the glass substrate G.

As described above, although the compressive stress is generated in the vicinity of the heated beam spot LS by the irradiation of the laser beam LB, since the cooling spot CP is formed by the injection of the coolant immediately thereafter, a tensile stress is effectively generated in the formation of cracks. This tensile stress forms a vertical crack along the planned scribing line SL starting from the initial crack TR formed at the end of the glass substrate G to form a desired scribe groove.

Since the crack regulating groove S is formed at the end portion of the line to be scribed SL, that is, the periphery of the glass substrate G, cracks propagating along the line to be scribed SL are formed in the groove S Stop by. Therefore, the crack does not advance to the entire depth of the glass substrate G, and it is possible to prevent the substrate from naturally being divided.

- Second Embodiment -

Fig. 2 shows an embodiment related to another method. In this embodiment, only the position where the crack regulating groove is formed is different from the embodiment of Fig. 1, and the other method is the same as the embodiment of Fig.

Specifically, in the scribe groove forming step, which is a next step, as a pre-step or a post-step of forming the initial crack TR, the direction from the initial crack TR to the direction in which the cracks are advanced (laser beam LB) A crack regulating groove S is formed in order to prevent cracks from advancing in a direction opposite to the direction of the cracks. This groove S is formed between the initial crack TR on the surface of the glass substrate G and the edge Ge of the glass substrate G. [ The crack regulating groove S is formed with a predetermined width in a direction perpendicular to the direction in which the planned scribing line SL extends.

In addition, the depth and the number of the crack restricting grooves S are the same as those in the first embodiment. That is, the depth of the crack regulating groove S is preferably formed shallower than the depth of the scribe groove formed in the later process. The crack regulating groove S may be formed corresponding to each of the plurality of scribing lines SL and may be one groove orthogonal to all the scribing lines SL.

The initial crack TR and the glass substrate G can be prevented from cracking even if the crack progresses in the direction opposite to the scanning direction of the laser beam LB from the initial crack TR in the scribe groove forming step. The cracks are stopped in the crack regulating groove S because the crack restricting grooves S are formed between the edge portions of the cracks. Therefore, it is possible to avoid cracks from being propagated from the initial cracks TR to the edge Ge of the glass substrate G to form deep cracks at the edge portions of the glass substrate G. Thereby, it is possible to prevent the glass substrate G from being divided naturally.

[Experimental Example]

[Verification about division of glass substrate]

&Lt; Experimental Example by Conventional Example &

Fig. 3 shows an example in which laser heating and cooling are performed from the start end to the end end (end end) of the line to be scribed without forming the crack regulating groove S in the conventional method. The substrate is tempered glass having a total thickness of 0.7 mm and a reinforcing layer thickness of 18 탆. The conditions of the laser beam are 200 W laser output and 200 mm / sec scanning speed. Incidentally, in Fig. 3, the end region of the glass substrate is not shown.

3 (a) shows a state immediately after scribing. Here, the scribe groove is a state in which the scribe groove does not extend over the entire depth of the substrate (hereinafter, this state is referred to as " half cut ") and is shown as a thin line in the drawing.

3 (b) shows a state after 5 seconds from the scribe process. Here, a scribe line is shown as a full cut (indicated by a thick line in the drawing) from the start side of the scribe (right side of the figure) to the center of the figure.

3 (c) shows a state after 20 seconds from the scribing process. Here, in all the portions shown in the drawings, the scribe lines are full-cut (indicated by a dark line in the drawing).

In this way, when the scribe grooves are formed by laser heating and cooling all over the area from the start end to the end end of the scribing line, the substrate is naturally divided (full cut).

By forming the crack regulating groove S between the end portions of the lines to be scribed SL, that is, 10 to 20 mm from the end face of the glass substrate G, A full cut of the substrate could be avoided.

By forming the crack regulating groove S between the initial crack TR and the edge Ge of the glass substrate G, cracks are generated from the initial crack TR toward the substrate edge Ge So that it is possible to avoid the full cut of the substrate, that is, the natural division.

Incidentally, in any of the cases, the groove S is formed shallower than the depth of the scribe groove to be formed.

[A Study on Initial Cracking]

In the method of the present embodiment, the depth of the initial crack or the like greatly affects the manufacturing quality. Therefore, an experimental example concerning the depth of the initial crack is shown below.

Fig. 4 shows Experimental Example 1 in which a scribe groove is formed on tempered glass having a total thickness of 0.55 mm and a thickness of the reinforcing layer of 18 m. Specifically, FIG. 4 shows the relationship between the load of the pressing of the tool against the glass at the time of forming the initial crack and the depth of the groove at that time, and the subsequent laser heating and cooling processing FIG.

The laser output for the heat treatment in this case is 200 W and the processing speed is 230 mm / sec. The cooling condition is such that a cooling nozzle is disposed at the rear end of the beam, and the cooling water and air are discharged to a portion heated by the beam spot.

It can be seen from Experimental Example 1 that if the groove depth of the initial crack is 19 to 30 占 퐉 (1.05 to 1.67 times the thickness of the reinforcing layer), a desired scribe groove is formed along the planned scribing line. When the groove depth is less than 19 탆, the cracks do not evolve securely (unstable). When the groove depth exceeds 30 탆, splitting occurs, and cracks are formed in other than the planned scribing line.

In addition, an example of the groove depth of the initial crack is shown in Fig. As shown in Fig. 5, the depth to the deepest portion where a predetermined area is ensured is referred to as " groove depth ", and the crack reaching the deep portion in some sharply is ignored .

[Experimental Example 2]

6 shows Experimental Example 2 in which a scribe groove is formed in tempered glass having a total thickness of 0.7 mm and a thickness of the reinforcing layer of 21 m. The relationship between the horizontal axis and the vertical axis in the figure is the same as that in FIG. The laser output for the heat treatment in this case is 200 W and the processing speed is 170 mm / sec. The cooling conditions were the same as those in Experimental Example 1.

It can be seen from Experimental Example 2 that a desired scribe groove is formed along the planned scribing line when the groove depth of the initial crack is about 24 to 50 mu m (1.14 to 2.38 times the thickness of the reinforcing layer). When the groove depth is less than 24 占 퐉, cracks do not evolve securely (unstable). When the groove depth is more than 50 占 퐉, splitting occurs, and cracks are formed in addition to the planned scribing line. In addition, if the pressing load is about 6 to 24N, a desired scribe groove is formed even if the groove depth exceeds 50 占 퐉. However, if only the groove depth is applied, the groove depth of the initial crack is about 24 to 50 占 퐉.

[Experimental Example 3]

7 shows Experimental Example 3 in which a scribe groove is formed on tempered glass having a total thickness of 1.1 mm and a thickness of the reinforcing layer of 34 m. The relationship between the abscissa and the ordinate in the figure is the same as in Fig. The laser output for the heat treatment in this case is 200 W and the processing speed is 170 mm / sec. The cooling conditions were the same as those in Experimental Example 1.

It can be seen from Experimental Example 3 that a desired scribe groove is formed along the planned scribing line when the groove depth of the initial crack is about 24 to 60 mu m (0.71 to 1.76 times the thickness of the reinforcing layer). When the groove depth is too shallow, the crack does not advance, and when the groove depth is more than 60 μm, the crack propagation is unstable. In addition, as in Experimental Example 2, if a pressing load is about 6N to 24N, a desired scribe groove is formed even if the groove depth exceeds 60 mu m. However, if only the groove depth is taken into consideration, the groove depth of the initial crack is about 24 to 60 mu m Do

[theorem]

From the above, it can be understood that the depth of the initial crack is preferably 1.0 times or more and 2.0 times or less the thickness of the reinforcing layer of the tempered glass in order to form a desired scribe groove along the planned scribing line. The depth of the initial crack is preferably 30 μm (5.5%) or less when the thickness of the glass plate is 0.55 mm, 50 μm (7.1%) or less when the thickness of the glass plate is 0.7 mm and 60 μm (5.4% . This indicates that the depth of the initial crack is preferably 7% or less of the thickness of the glass even at the maximum.

[Characteristic]

- First Embodiment -

(1) Since the grooves S for stopping crack growth and stopping perpendicular to the planned scribing line SL are formed in the end portion of the planned scribing line SL, that is, the end region on the scanning end side, And it is possible to avoid the natural division of the substrate. Therefore, a subsequent machining process such as cross-scribing becomes easy.

(2) Because grooves are formed as means for stopping the crack propagation at the end portion of the scribing line, natural division of the substrate can be avoided by a simple method.

- Second Embodiment -

(1) Since the groove S for regulating the crack is formed between the initial crack and the substrate edge at the starting end of the planned scribing line SL, which is perpendicular to the planned scribing line SL, It is possible to prevent the crack from advancing from the initial crack toward the substrate edge. Therefore, it is possible to avoid formation of a deep crack in the edge portion of the substrate, and natural division of the substrate due to the deep crack can be avoided. Therefore, a subsequent machining process such as cross-scribing becomes easy.

(2) Since the formation of a crack from the initial crack toward the substrate edge can be regulated, the offset amount of the initial crack from the substrate edge can be reduced. Therefore, the portion of the substrate that can not be secured as a product is reduced, and the yield of the product can be improved.

(3) Because grooves are formed as means for stopping the crack from the initial crack toward the substrate edge, natural partitioning of the substrate can be avoided by a simple method.

(4) Since the initial cracks and the crack restricting grooves are formed apart from each other, it is possible to more reliably stop the cracks from the initial cracks toward the substrate edge.

- Common features -

(1) Since the crack restricting grooves are locally formed, generation of dust and the like can be suppressed as much as possible, and deterioration of the quality of the glass substrate can be avoided.

[Other Embodiments]

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

It is preferable that the grooves for crack propagation stop are formed so as to be orthogonal to the planned scribing line, but they may not be orthogonal if they are formed so as to intersect the planned scribing line.

G: glass substrate
LB: laser beam
LS: Beam spot
SL: Scheduled line to be scribed
CP: Cooling spot
TR: initial crack
S: Crack regulating groove

Claims

A scribing method of a glass substrate scribing a glass having a reinforcing layer having a compressive stress on a surface thereof,
A crack regulating groove forming step of forming a crack regulating groove on the surface of the glass having a predetermined width in a direction intersecting with a planned scribing line at a terminal end of a line to be scribed,
A scribe groove forming step of forming a scribe groove by advancing a crack along a planned scribing line by cooling the heated region and irradiating the glass surface with laser light and heating it,
/ RTI >
Further comprising an initial crack forming step of forming an initial crack on the surface of the glass by removing a part of the strengthening layer as a previous step of the scribe groove forming step,
Scribing method of glass substrate.

delete

A scribing method of a glass substrate scribing a glass having a reinforcing layer having a compressive stress on a surface thereof,
An initial crack forming step of removing at least a portion of the reinforcing layer on the surface of the glass to form an initial crack,
A scribe groove forming step for forming a scribe groove by irradiating a laser beam onto the surface of the glass and heating it, cooling the heated area to advance the initial crack along the planned scribe line,
In order to regulate the advance of the initial crack in the scribe groove forming step in the direction opposite to the crack propagation direction, it is preferable that, as the pretreatment or post-treatment of the initial crack forming step, A crack regulating groove forming step of forming a crack regulating groove having a predetermined width in a direction intersecting with a direction in which the planned scribing line extends from between the initial crack and the edge of the glass substrate
And scribing the glass substrate.

The method according to claim 1 or 3,
Wherein the crack regulating groove is formed so as to extend in a direction perpendicular to the line to be scribed in the crack regulating groove forming step.

The method according to claim 1 or 3,
Wherein the crack regulating groove is formed shallower than the depth of the scribe groove formed in the scribe groove forming step in the crack regulating groove forming step.

The method according to claim 1 or 3,
Wherein an initial crack formed in the initial crack forming step and a groove formed in the crack regulating groove forming step are formed with a gap therebetween.