JP2017014031A - Scribe method and scribe device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a scribe method and a scribe device, capable of accurately forming a crack for segmentation.SOLUTION: A surface of a glass substrate M on an adsorptive table 1 is heated by a laser B1 for glass heating, and a heated region is quickly cooled by coolant. Then, crack S for segmentation is created along the scribe planned line on the surface of the glass substrate M, by extending a trigger formed at a tip of the scribe planned line by heat stress raised in the glass substrate M, in the scribe method and the device. The surface of the glass substrate M is irradiated with the laser B1 for glass heating in a state that the glass substrate M is stuck to the resin sheet 20 and adsorbed to the adsorptive table 1, and at the same time, a sheet heating beam B2 of a wave length, which is transmitted through the glass substrate M and adsorbed to the resin sheet 20 is applied together with the laser B1 for glass heating, to an irradiation point of the laser B1 for glass heating, and thereby, the crack S is formed on the glass substrate M.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a scribing method and a scribing apparatus for processing a splitting crack in a thin glass substrate made of alkali-free glass or the like. In particular, the present invention relates to a scribing method and a scribing apparatus for scribing a thin glass substrate used in a flat panel display (FPD) such as a liquid crystal display or a plasma display.

  Conventionally, using a laser scribing method that scans while irradiating a laser beam and generates a thermal stress distribution on the substrate to perform scribing, for example, as in Patent Document 1, a split crack (crack) is formed, Or the technique of carrying out complete parting (full cut processing) like patent document 2 is known.

In the conventional laser scribing method, as shown in FIG. 6A, a glass substrate M is mounted and fixed on a suction table 21 having a large number of air suction holes, and laser light 22 such as a CO ₂ laser is used. The vicinity of the surface of the glass substrate M is scanned and heated along the scheduled scribe line L, and the coolant 23 is jetted from the nozzle of the cooling mechanism to the heating region following this. In addition, the code | symbol E1 shows the heating area | region by the laser beam 22, and the code | symbol E2 shows the quenching area | region by the refrigerant | coolant 23. FIG. As a result, as shown in FIG. 6B, the trigger (initial crack) T is developed by the thermal stress distribution caused by the compressive stress P1 generated by the preceding heating and the tensile stress P2 generated by the subsequent rapid cooling, and the glass substrate M A crack S for cutting is generated on the surface, or the full thickness is processed by infiltrating the crack S in the entire thickness.

  The adsorption table for adsorbing and holding the glass substrate during scribing is made of a metal plate having a large number of suction holes made by machining on a metal plate and a porous plate such as a ceramic having a large number of pores. Some of them are formed and sucked with air during laser scribing to hold the glass substrate. However, in recent years, the thinning of the glass substrate has progressed due to the reduction in the weight and thickness of video display devices such as smartphones, and thus, for example, a thin film-like glass substrate of 0.2 mm or less has been required. If such a thin glass substrate is adsorbed by an adsorption table, the following problems occur and laser scribing becomes difficult.

  In general, the hole diameter of the suction holes provided in the metal table is about 1 to 2 mm, and the hole diameter of the pores of the porous plate table is smaller than that and is about 50 to 60 μm. When laser scribing is performed by directly adsorbing the glass substrate to the openings of the suction holes and pores, the heat dissipation due to the presence or absence of contact with the adsorption table between the vicinity of the opening and the flat part without the opening is caused. A difference will arise in the thermal stress in a glass substrate. This difference in thermal stress becomes even more pronounced with thin glass substrates of 0.2 mm or less, and it becomes impossible to generate thermal stress evenly over the entire length of the scribe line, resulting in incomplete cracks or unevenness. Therefore, laser scribing with high accuracy cannot be performed. Further, in the case of a thin glass substrate, heat is taken away by direct contact with the table surface, and there is a problem that thermal stress cannot be sufficiently exhibited in the substrate and cracks become insufficient.

International Publication WO2003 / 008352 JP 2001-170786 A

  Therefore, as shown in FIG. 7, the present applicant attaches a resin sheet 20 ′ to a glass substrate M and places the resin sheet 20 ′ on the lower surface and places the resin sheet 20 ′ on the suction table 1 made of a porous plate. I applied for a method of scribing earlier.

  According to this method, the unevenness of the thermal stress caused by the suction holes can be solved, and the formation of the crack S is promoted by interposing the resin sheet 20 ′ between the suction table 1 and the glass substrate M. .

However, since the laser used to generate thermal stress in the glass substrate is generally a CO ₂ laser or the like in which thermal energy is easily absorbed by the glass, the output is appropriate for generating thermal stress. When the laser is irradiated, the amount of heat transferred from the glass substrate to the lower resin sheet is small. Therefore, since the rise due to the thermal expansion of the resin sheet is reduced, the effect of promoting cracks cannot be expected so much, the instability remains in crack formation accuracy, and when the laser scanning speed is increased, the resin sheet is sufficiently The resin sheet cannot be heated and cannot be thermally expanded. Moreover, since the appropriate range for generating the thermal stress due to the laser output is limited, the laser output cannot be increased more than necessary to increase the amount of heat transmitted from the glass substrate.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a scribing method and a scribing device that can reliably and accurately form a deep crack for cutting by laser scribing.

  In order to achieve the above object, the present invention takes the following technical means. That is, the present invention heats the surface of the glass substrate adsorbed on the adsorption table along the scribe line using a glass heating laser, and rapidly cools the heating region with a refrigerant, thereby A scribing method in which a trigger formed at a leading portion of the scribe line is developed by a thermal stress generated in the scribe line, and a crack for breaking along the scribe line is generated on the surface of the glass substrate, the glass substrate The surface of the glass substrate is irradiated with the laser for heating the glass with the glass substrate facing upward and held on the suction table with the glass substrate facing upward, and at the same time, the glass substrate is transmitted through the glass substrate. A sheet heating beam having a wavelength absorbed by the resin sheet is directed toward the irradiation point of the glass heating laser. By irradiating with the glass heating laser, and forming cracks in the glass substrate along the scribed line.

The sheet heating light beam is preferably a light beam having a wavelength of 0.3 to 2.0 μm, for example, green light, which is transmitted through the glass substrate and absorbed by the resin sheet.
The resin sheet has a thickness of 50 to 200 μm and an expansion coefficient of 50 × 10 ^{−6 to} 400 × 10 ⁻⁶ , for example, polyvinyl chloride, polyethylene, polyethylene terephthalate, polyvinylidene chloride, polyvinylidene fluoride. , Silicon rubber, polyurethane resin and the like.

  In addition, the present invention heats the surface of the glass substrate adsorbed on the adsorption table along a scribe line using a glass heating laser, and rapidly cools the heating region with a refrigerant. A scribing device that develops a trigger formed at a head portion of the planned scribe line by the generated thermal stress and generates a crack for splitting along the planned scribe line on the surface of the glass substrate, wherein the glass substrate is , Having a laminated structure in which a resin sheet is attached to the lower surface thereof, and configured to be sucked and held by the suction table in a state in which the glass substrate is faced upward, apart from the glass heating laser, A light source that irradiates a sheet heating beam having a wavelength that passes through the glass substrate and is absorbed by the resin sheet is provided. When the glass heating laser is irradiated with the glass heating laser simultaneously with the irradiation of the glass heating laser, the glass substrate is cracked along the planned scribe line. The scribe device is also characterized.

  The glass substrate may be a three-layer substrate in which a resin sheet is interposed between two glass substrates.

  According to the present invention, apart from the glass heating laser for generating thermal stress on the glass substrate, the resin sheet is heated by a sheet heating beam having a wavelength that is transmitted through the glass substrate and absorbed by the resin sheet. The thermal expansion of the resin sheet causes the upper glass substrate to bulge into a convex shape, which increases the tensile stress on the glass substrate surface generated by the thermal stress caused by the laser and ensures deep cracks. In addition, there is an effect that processing can be performed with high accuracy.

  In addition, in the present invention, since the resin sheet is interposed between the glass substrate and the suction table when scribing with the glass heating laser, there is no opening portion in the vicinity of the suction opening of the suction table. There is no difference in downward heat dissipation between the locations, and unevenness in the generation of thermal stress inside the glass substrate can be eliminated. This also has the effect that the thermal stress can be uniformly generated over the entire length of the scribe line, and a crack can be stably formed.

1 is a schematic front view showing an embodiment of a scribing apparatus according to the present invention. Sectional drawing which shows the adsorption | suction table in this invention. Explanatory drawing which shows the scribing method of this invention. Explanatory drawing which expands and shows the crack part formed by this invention. Explanatory drawing which shows another Example of this invention. Explanatory drawing which shows the conventional laser scribing method. Explanatory drawing at the time of sticking a resin sheet on the substrate lower surface at the time of laser scribing.

  Hereinafter, the details of the present invention will be described based on the embodiments shown in the drawings. In this embodiment, a film-like non-alkali glass plate having a thickness of 0.03 to 0.2 mm is used as the glass substrate to be processed.

FIG. 1 shows a scribing apparatus A used in the method of the present invention, and includes a suction table 1 on which a glass substrate M is placed and sucked and held.
As shown in FIG. 2, the suction surface of the suction table 1 is formed of a porous plate 3 made of ceramic or carbon having a large number of pores. The porous plate 3 is held by a frame member 4, and the chamber 5 formed below is sucked by a suction pump P, thereby generating a suction force in the pores serving as the suction openings, and holding the glass substrate M by suction. It is formed as follows.
The porous plate 3 is preferably formed with a pore diameter of 1 to 10 μm and a porosity of 10 to 40%. In this embodiment, the porous plate 3 is formed with a pore diameter of 5 μm and a porosity of 35%.
The suction table 1 can be moved in the Y direction (front-rear direction in FIG. 1) along a horizontal rail 6 and is driven by a screw shaft 7 that is rotated by a motor (not shown). Further, the suction table 1 can be rotated in a horizontal plane by a rotation drive unit 8 incorporating a motor.

  A bridge 11 provided with support columns 9 and 9 on both sides of the suction table 1 and a beam (horizontal beam) 10 extending horizontally in the X direction is provided so as to straddle the suction table 1. Yes. The beam 10 is provided with a guide 12 extending horizontally in the X direction. The guide 12 includes a laser irradiation unit 13 that irradiates a glass heating laser B1, a refrigerant injection nozzle 14 that rapidly cools a heated portion immediately after laser irradiation, and a light source 15 that irradiates a sheet heating light beam B2. 16 is attached. Further, the guide 12 is provided with a scribe head 18 that holds a cutter wheel 17 for processing a trigger (initial crack) at a head portion of a scheduled scribe line of the glass substrate M. The scribe heads 16 and 18 can be moved in the X direction along the guide 12 by a moving mechanism (not shown) using a motor 19 as a drive source.

Next, the scribing method of the present invention using the above apparatus will be described with reference to FIGS.
As the glass heating laser B1 irradiated from the laser irradiation unit 13, a laser beam such as a CO ₂ laser that is easily absorbed by glass is used.
Further, the sheet heating light beam B2 irradiated from the light source 15 has a wavelength that is transmitted through the glass substrate M and absorbed by the resin sheet 20, and thermally expands the resin sheet 20 bonded to the lower surface of the glass substrate M. A light beam having heat energy that can be used is used. As this light beam, for example, a light beam having a wavelength of 0.3 to 2.0 μm or green light can be used. As the light source, a semiconductor laser or a near infrared light source can be used.

First, the glass substrate M is affixed on the resin sheet 20, placed on the suction table 1 with the resin sheet 20 facing down, and held by suction.
The resin sheet 20 has a thickness of 50 to 200 μm, and has a high coefficient of linear expansion and a heat-resistant temperature, and is likely to increase in temperature (low thermal conductivity and low specific heat), that is, an expansion coefficient of 50 × 10 ^−. A resin material of ^{6 to} 400 × 10 ⁻⁶ is used. As this resin material, for example, polyvinyl chloride, polyethylene, polyethylene terephthalate, polyvinylidene chloride, polyvinylidene fluoride, silicon rubber, polyurethane and the like can be used.
In addition, it is preferable that the resin sheet 20 is colored in a color in which the light of the sheet heating light beam B2 is easily absorbed, for example, black.

  Prior to laser scribing, a trigger is processed by the cutter wheel 17 at a portion of the surface of the glass substrate M which becomes the tip of the scribe line. The processing of the trigger is formed by lowering the cutter wheel 17 toward the surface of the glass substrate M at a position slightly inside from the edge of the glass substrate M. As the cutter wheel 17 for processing the trigger, for example, a grooved cutter wheel in which grooves (notches) and cutting edges are alternately formed along a circumferential ridgeline may be used.

Next, starting from the trigger, the laser irradiation unit 13 scans and heats the glass heating laser B1 along the scheduled scribe line, and the refrigerant is jetted from the refrigerant jet nozzle 14 to the heating region following this. As a result, a splitting crack S starting from the trigger is formed along the scheduled scribe line by the thermal stress distribution due to the compressive stress P1 generated by the preceding heating and the tensile stress P2 generated by the subsequent rapid cooling.
Furthermore, simultaneously with this laser scribing, the sheet heating light beam B2 is irradiated toward the irradiation point of the glass heating laser B1, and scribing is performed along the planned scribe line together with the glass heating laser B1. Thereby, as the heated portion of the resin sheet 20 is thermally expanded and swells upward, the portion where the thermal stress of the glass substrate M is generated swells upward in a convex shape. Due to the convex rise of the glass substrate M, the tensile stress of the material itself generated on the surface side of the glass substrate M promotes the tensile stress P2 of the thermal stress, and the deep crack S can be processed with high accuracy.

  Further, in the present invention, since the resin sheet 20 is interposed between the glass substrate M and the suction table 1 at the time of laser scribing, the suction table 1 near the suction opening portion and the portion without the opening portion. Since there is no difference in heat dissipation downward, there is no unevenness in the generation of thermal stress inside the glass substrate M. As a result, thermal stress can be evenly generated over the entire length of the scribe line, and the crack S can be formed cleanly without unevenness.

In the above embodiment, laser scribing of a two-layer structure substrate in which the resin sheet 20 is bonded to the glass substrate M has been described. However, as shown in FIG. 6, the resin sheet is interposed between the upper and lower glass substrates M and M. Also for a three-layered substrate with 20 interposed, a crack S for cutting can be formed by laser scribing by the same means as in the above embodiment.
That is, as in the previous embodiment, the substrate surface of the three-layer structure placed on the suction table 1 is heated by irradiating the glass heating laser B1 from the laser irradiation unit along the planned scribe line. The heating area is quenched with a refrigerant. In the same manner as in the previous embodiment, simultaneously with the glass heating laser B1, the sheet heating beam B2 is irradiated and scribed along a scribe line.
Also in this case, the heated portion of the intermediate resin sheet 20 is thermally expanded by the sheet heating light beam B2, and the upper glass substrate M rises upward, whereby the tensile stress P2 is increased and the crack S is reliably formed. can do.

  In this embodiment, the crack S formed by laser scribing is not completely divided, but the target value is 70 to 90% of the entire thickness of the glass substrate M. However, the crack S penetrates the entire thickness. Of course, it is possible to divide completely.

  While typical examples of the present invention have been described above, the present invention is not necessarily limited to the above-described embodiments, and can be appropriately modified and changed within the scope of achieving the object and not departing from the scope of the claims. Is possible.

  The present invention is mainly used for laser scribing for forming a splitting crack in a thin glass substrate having a thickness of 0.03 to 0.2 mm.

A Scribing device B1 Glass heating laser B2 Sheet heating beam M Glass substrate P1 Compressive stress P2 Tensile stress S Crack 1 Suction table 13 Laser irradiation unit 14 Refrigerant jet nozzle 15 Light source 20 Resin sheet

Claims (8)

The surface of the glass substrate adsorbed on the adsorption table is heated along the scribe line using a glass heating laser, and the heating region is rapidly cooled with a refrigerant, thereby generating the thermal stress generated in the glass substrate. A scribing method for developing a trigger formed at the beginning of a scribe line and causing a crack for dividing along the scribe line on the surface of the glass substrate,
The glass substrate is affixed on a resin sheet, and the glass substrate is irradiated with the glass heating laser with the glass substrate facing upward and held on the suction table, and simultaneously transmitted through the glass substrate. By irradiating the sheet heating light beam having a wavelength absorbed by the resin sheet with the glass heating laser toward the irradiation point of the glass heating laser, the glass substrate along the planned scribe line. A scribing method characterized by forming a crack in the surface.   The scribing method according to claim 1, wherein the sheet heating light beam is transmitted through the glass substrate and absorbed by the resin sheet, and has a wavelength of 0.3 to 2.0 μm. The scribing method according to claim 1, wherein the resin sheet has a thickness of 50 to 200 μm and an expansion coefficient of 50 × 10 ^{−6 to} 400 × 10 ⁻⁶ .   The scribing method according to any one of claims 1 to 3, wherein a material of the resin sheet is selected from polyvinyl chloride, polyethylene, polyethylene terephthalate, polyvinylidene chloride, polyvinylidene fluoride, silicon rubber, and polyurethane resin.   The scribing method according to any one of claims 1 to 4, wherein the resin sheet is colored in a color that is easily absorbed by heat.   The scribing method according to any one of claims 1 to 5, wherein the glass substrate has a thickness of 0.03 to 0.2 mm. The surface of the glass substrate adsorbed on the adsorption table is heated along the scribe line using a glass heating laser, and the heating region is rapidly cooled with a refrigerant, thereby generating the thermal stress generated in the glass substrate. A scribing device that develops a trigger formed at the beginning of a scribe line and causes a crack for cutting along the scribe line on the surface of the glass substrate,
The glass substrate has a laminated structure in which a resin sheet is attached to the lower surface thereof, and is configured to be sucked and held by the suction table with the glass substrate facing upward,
In addition to the glass heating laser, a light source is provided that irradiates a sheet heating beam having a wavelength that passes through the glass substrate and is absorbed by the resin sheet.
The sheet heating beam forms a crack in the glass substrate along the planned scribe line by irradiating with the glass heating laser simultaneously with the irradiation of the glass heating laser and toward the same irradiation point. A scribing device characterized by that.   The scribing apparatus according to claim 7, wherein the glass substrate is formed in a three-layer structure in which a resin sheet is interposed between two glass substrates.

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