KR20130045166A

KR20130045166A - Scribe method for glass substrate and scribe processing apparatus for glass substrate

Info

Publication number: KR20130045166A
Application number: KR1020120094034A
Authority: KR
Inventors: 유 항 수; 타케시 이케다; 코지 야마모토
Original assignee: 미쓰보시 다이야몬도 고교 가부시키가이샤
Priority date: 2011-08-30
Filing date: 2012-08-28
Publication date: 2013-05-03
Also published as: CN102964059A; JP2013049588A; TWI491573B; TW201313639A; CN102964059B; JP5437333B2; KR101396990B1

Abstract

PURPOSE: A scribing method and a processing device thereof are provided to stably form a scribe groove on tempered glass by holding a glass edge of a predetermined scribing line with a strong adhesion force. CONSTITUTION: A scribing method of a glass substrate comprises the following steps: placing glass on a table which has a plurality of adsorption holes for holding the substrate and suctioning a glass end on an edge side of a predetermined scribing line of the glass with a stronger adhesion force than the center part; forming a premature crack on the glass surface; and heating the glass surface with a laser light, cooling the heated area, and forming a scribe groove by progressing the crack along the predetermined scribing line. A processing device of the glass substrate comprises a table(2), a laser irradiating part(4), a cooling part(5), a mobile tool, and a suction pressure controlling part(8). The suction pressure controlling part controls the suction pressure on the table.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a method of scribing a glass substrate,

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 its surface along a planned scribing line. It also relates to a processing apparatus for scribing glass.

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. In this method, however, 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 grooves, 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 scribe grooves are not formed is formed at the terminal end portion of the scribing line. 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.

Japanese Patent Application Laid-Open No. 3-489 Japanese Patent Application Laid-Open No. 9-1370 Japanese Patent Laid-Open Publication No. WO2007 / 094348

However, in the FPD (flat panel display) industry in recent years, since the strength of the cross section 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 a cross-section 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 , Experimentally found that it is divided into natural parts. 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 this deep crack is caused by the development along the scribe grooves. The reason why the scribe groove is deepened in the periphery of the glass substrate is considered as follows.

At the end portion of the glass substrate on which the scribe groove is formed, since the cross section is not constrained, both sides of the scribe groove are likely to spread.

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 carry out a post-treatment.

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.

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

A method of scribing 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 along a planned scribing line, and has the following steps.

Step 1: Glass is placed on a table having a plurality of suction holes for holding a substrate, and a glass end on the end side of the line to be scribed of glass, Is adsorbed at a strong adsorption pressure compared with the central portion.

Second step: Initial cracks are formed on the surface of the glass.

Third step: The surface of the glass is irradiated with a laser beam to be heated, and the heated area is cooled, and cracks are developed along the planned scribing line to form scribe grooves.

Here, first, the glass to be processed is placed on the table. On the table, a plurality of adsorption holes are provided, and the glass is sucked through the adsorption holes and held at a predetermined position of the table. At this time, the glass end portion on the end side of the line to be scribed is attracted and held by the stronger force as compared with the other region. After the initial crack is formed, the glass surface is irradiated with laser light to be heated, and further the heated region is cooled. By this heating and cooling process, the initial cracks propagate along the planned scribing line, and scribe grooves are formed.

In this method, the glass end on the end side of the line to be scribed is held on the table with stronger attraction force. Therefore, the glass end portion is less likely to deform when heated and cooled. As a result, cracks do not easily spread at the glass end, formation of deep cracks can be suppressed, 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 which concerns on 2nd invention is the scribing method of 1st invention WHEREIN: In a 1st process, strong adsorption is carried out compared with the glass end of the start end side of the scribe plan line of glass compared with a center part. Adsorbed by pressure.

For example, when the depth of the groove of the initial crack is deep, in the process of forming the scribe groove (the third step), cracks are generated in a direction opposite to the scanning direction of heating and cooling from the initial crack, , Which may cause natural division.

Thus, in the second invention, the glass end on the start end side of the line to be scribed is held with strong attraction force. Thus, deformation of the glass end portion at the time of formation of the scribe groove is suppressed, and crack propagation toward the start end side of the line to be scribed can be suppressed. Therefore, natural division can be avoided.

The scribing method of the glass substrate according to the third invention is the scribing method according to the first invention, wherein in the third step, the scribe grooves are formed along a plurality of scribing lines perpendicular to each other. In the first step, the entire outer circumferential end of the glass is compared with the other regions and adsorbed by strong adsorption pressure.

In this case, when cross-scribing is performed, it is possible to suppress formation of deep cracks at the glass end portion as in the above, and natural division can be avoided.

A glass substrate processing apparatus according to a fourth aspect of the present invention is an apparatus for scribing a glass having a reinforcing layer having a compressive stress on a surface thereof along a planned scribing line and is provided with a table, an irradiating section, a cooling section, . The table has a plurality of suction holes, and adsorbs and holds the glass placed on the surface. The irradiation part irradiates the laser beam onto the glass. The cooling part cools the heated area by the irradiation part. The moving means relatively moves the irradiation unit and the cooling unit along the scheduled scribing line set in the glass. The suction pressure control unit controls the suction pressure in the table so that at least the end of the end of the glass to be scribed line on the longitudinal side is strengthened compared to the central portion.

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 portion 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.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic block diagram of an apparatus for carrying out a scribing method according to an embodiment of the present invention; FIG.
2 is a view showing a relationship between a substrate suction pressure on a table and a scribing process;

[Device configuration]

1 is a diagram showing a schematic configuration of a scribing apparatus for performing a method according to an embodiment of the present invention. 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 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 a table 2 on which a glass substrate G is placed, a cutter wheel 3, a laser irradiation unit 4, a cooling unit 5, a driving mechanism 6, Two suction pumps 7a and 7b, and a control unit 8. [0034]

In the table 2, a plurality of through holes 10 in which the upper portion is released to the table surface are formed. The through hole 10a formed at the position corresponding to the outer peripheral end of the glass substrate G among the plurality of through holes 10 is connected to the first suction pump 7a through the first passage 11 indicated by the solid line have. A 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 a one-dot chain line.

The cutter wheel 3 is a tool for forming an initial crack at the end of the glass substrate G serving as a starting point of the scribe. The cutter wheel 3 mainly has a holder and a scribing wheel supported by the holder.

The laser irradiation unit 4 has a laser oscillator (for example, a CO ₂ laser) that irradiates a laser beam and irradiates the laser beam as a beam spot on the glass substrate G through an optical system . The cooling section 5 also forms a cooling spot by injecting a coolant (for example, water, air, helium gas, etc.) supplied from a coolant source (not shown) through a nozzle.

The drive mechanism 6 is a mechanism for moving the cutter wheel 3, the laser irradiation part 4 and the cooling part 5 along the rail 14. [ The cutter wheel 3, the laser irradiation unit 4 and the cooling unit 5 are moved along the planned scribing line set on the glass substrate G by the drive mechanism 6. [

The control unit 8 controls the cutter wheel 3, the laser irradiation unit 4, the cooling unit 5, the driving mechanism 6, and the two suction pumps 7a and 7b. Specifically, the control unit 8 controls the pressure of the cutter wheel 3 to be applied to the glass substrate G, the pressure of the cutter wheel 3, the laser output, the amount of the coolant injected, (Adsorption pressure) of the adsorbent 7a, 7b is controlled.

[Relationship between Substrate Adsorption Pressure and Scribe]

The results of the scribing in the case where the laser output and the scanning speed are changed and the adsorption pressure is changed under the respective conditions are shown below. The summary of each experimental example is shown in Fig.

The adsorption pressure (kPa) of the glass substrate (G) on the table (2): 5, 10, 20

Laser output: 140W

Scanning speed: 190 mm / s

In Experimental Example 1, scribing was possible at a low adsorption pressure of 5 kPa (indicated by "O" in FIG. 2), but scribing was not possible at a high adsorption pressure of 10 and 20 kPa (indicated by "x" in the figure).

Laser power: 160W

Scanning speed: 230mm / s

In Experimental Example 2, scribing was possible at the adsorption pressure of 5 and 10 kPa, but scribing was not possible at the adsorption pressure of 20 kPa.

Laser power: 170W

Scanning Speed: 250mm / s

In Experimental Example 3, scribing was possible at the adsorption pressure of 5 and 10 kPa, but scribing was not possible at the adsorption pressure of 20 kPa.

Laser power: 180W

Scanning speed: 260 mm / s

In Experimental Example 4, scribing was possible at the adsorption pressure of 5 and 10 kPa, but scribing was not possible at the adsorption pressure of 20 kPa.

As is evident from the above experimental example, it can be seen that, when the suction pressure is increased, that is, the suction force is made strong, and the deformation of the glass substrate is suppressed at the time of forming the scribe groove, the progress of the crack is stopped.

[Scribe method]

Based on the above findings, in this embodiment, the scribe groove is formed by the following scribing method.

First, the glass substrate G to be processed is placed on the table 2. Then, the first suction pump 7a and the second suction pump 7b are driven to suck the glass substrate G onto the table 2. At this time, the control unit 8 controls the rotation speed of each of the suction pumps 7a and 7b, controls the suction pressure by the first suction pump 7a to be 20 kPa or more, controls the second suction pump 7b, Is controlled to be 10 kPa or less.

Next, the cutter wheel 3 is used to form an initial crack at the end portion of the glass substrate G serving as a starting point of the scribe.

Next, a 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 the scheduled scribing line. The glass substrate G is heated to a temperature lower than the softening point of the glass substrate G by the beam spot. Further, the cooling spots are made to follow the backward (rearward) direction of movement of the beam spot.

As described above, although a compressive stress is generated in the vicinity of the beam spot heated by the irradiation of the laser beam, since a cooling spot is formed by the injection of the coolant immediately thereafter, a tensile stress effective for forming a vertical crack is generated. Due to this tensile stress, a vertical crack is formed along the planned scribing line starting from the initial crack formed at the end of the glass substrate G, and a desired scribe groove is formed.

Here, in the step of forming the scribe groove, the start end and the end portion of the line to be scribed, that is, the end portion of the glass substrate G are held as a strong suction pressure (suction force). Therefore, the deformation of the glass substrate G by the heating and cooling processing is suppressed, and crack progression can be suppressed. Therefore, it is possible to suppress formation of a deep crack at the end portion of the glass substrate G, and it is possible to prevent the substrate from being divided naturally.

[Characteristic]

In this embodiment, since the end portion of the glass substrate is held on the table with a strong force to suppress deformation during processing, it is possible to suppress the formation of deep cracks in the end portion of the glass substrate. Therefore, natural division of the substrate can be avoided.

In addition, since the suction pressure of the substrate on the table is controlled by means of the means for stopping the crack propagation at the end portion of the glass substrate, the natural division of the substrate can be avoided by a simple method.

[Other Example]

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

(a) In the above embodiment, both the end on the start side and the end on the end side of the line to be scribed in the glass substrate are held on the table with a strong force, but the end on the end side of the line to be scribed It may be possible to have only a strong force. Further, if the end on the start side is held with a strong force, the advance of the initial crack is suppressed and the scribe groove may not be formed. Therefore, the end on the start side is weaker than the end on the end side, They may be compared with each other and viewed strongly.

(b) In the above embodiment, the table 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 table may be moved.

(c) In the above embodiment, the cutter wheel for forming the initial crack is provided in the same apparatus together with the laser irradiation unit. However, the cutter wheel may be provided in a separate apparatus from the laser irradiation unit or the like. In this case, after the initial crack is formed, the glass substrate is adsorbed on the table. That is, the order of the initial crack forming process (second process) and the step of placing the glass substrate on the table (the first process) are reverse to those of the above-described embodiment.

(d) In the above embodiment, the cutter wheel is used to form the initial crack. However, the laser beam such as laser ablation or modification may be used to form the initial crack. In this case, a laser irradiation mechanism using a UV laser or a green laser as a light source is provided for the initial crack formation.

1: scribe device
2: table
3: Cutter wheel
4: laser irradiation unit
5: Cooling section
6: Driving mechanism
7a, 7b: suction pump
8:
10: Through hole
G: glass substrate

Claims

A glass substrate scribing method for scribing a glass having a reinforcing layer having a compressive stress on a surface thereof along a line to be scribed,
The glass is placed on a table having a plurality of suction holes for holding a substrate and a glass end portion on the terminal end side of the glass scribing line is compared with a central portion to form a strong A first step of adsorbing the adsorbent by adsorption pressure;
A second step of forming an initial crack on the surface of the glass,
A third step of heating the surface of the glass by irradiating laser light and cooling the heated region to form a scribe groove by advancing the crack along the planned scribing line,
And scribing the glass substrate.

The method of claim 1,
The said 1st process WHEREIN: The scribing method of the glass substrate which adsorb | sucks by the strong adsorption pressure compared with the center part of the glass edge part of the start end side of the scribe plan line of glass.

The method of claim 1,
In the third step, scribe grooves are formed along a plurality of lines to be scribed orthogonal to each other,
In the first step, the entire outer circumferential end of the glass is compared with the other region and is adsorbed by a strong adsorption pressure,
Scribing method of glass substrate.

A glass substrate processing apparatus for scribing glass having a reinforcing layer having a compressive stress on its surface along a line to be scribed,
A table having a plurality of suction holes for adsorbing and holding glass placed on the surface,
An irradiation unit for irradiating the laser beam onto the glass,
A cooling unit for cooling the area heated by the irradiation unit,
Moving means for relatively moving the irradiation unit and the cooling unit along a planned scribing line set in the glass,
The suction pressure in the table is controlled so that at least the end of the glass on the longitudinal end side of the line to be scribed becomes stronger in comparison with the central portion,
And a processing unit for processing the glass substrate.