TWI507265B - Laser cutting apparatus - Google Patents

Description

Laser cutting device

The invention relates to a laser cutting device.

Conventionally, a brittle material substrate such as a glass substrate is cut by, for example, the following method. First, a cutter wheel or the like is pressed against the substrate and rotated, whereby a scribe line formed of a vertical crack is formed on the substrate. Thereafter, an external force is applied to the substrate in the vertical direction along the scribe line. Thereby, the substrate is cut along the score line.

As described above, when the brittle substrate material is scribed with a cutter wheel, mechanical stress is applied to the brittle material substrate, and the substrate is likely to be defective. Therefore, when an external force is applied to cut the substrate, damage may occur due to defects.

Therefore, in recent years, a method of cutting a brittle material substrate using a laser has been put to practical use. In this method, a laser beam is irradiated onto the substrate while the substrate is heated to a temperature below the melting temperature. Thereafter, the substrate is cooled by the cooling medium, and thereby thermal stress is generated on the substrate. The surface of the substrate is cracked in a substantially vertical direction by the thermal stress (hereinafter, there is a case where it is described as "vertical crack"). In such a cutting method of a brittle material substrate using a laser beam, since the thermal stress is utilized, the tool does not directly contact the substrate. Therefore, the cut surface of the substrate becomes a smooth surface with less defects, and the strength of the substrate is maintained.

In the laser cutting method as described above, in order to deepen the vertical crack, it is necessary to increase the irradiation output of the laser beam or to slow down the scanning speed. However, if the irradiation output of the laser beam is increased, damage due to heating occurs on the surface of the substrate. Moreover, if the scanning speed of the laser beam is slowed down, the processing efficiency is lowered.

Therefore, there is a technical proposal to bend the substrate and irradiate the laser in this state to deepen the vertical crack. For example, in Patent Document 1, the substrate is bent by suction-fixing the substrate on a stage. Further, in Patent Document 2, the height of the supporting member is changed, and the substrate is bent by the weight of the body.

[Previous Technical Literature] (Patent Literature)

[Patent Document 1] Japanese Patent Laid-Open No. Hei 7-323384

[Patent Document 2] Japanese Patent Laid-Open Publication No. 2007-191363

In the method disclosed in Patent Document 1, since the substrate is held on a land formed with a predetermined height of protrusions or a predetermined curved surface, if the substrate is to be bent into a desired shape, it is necessary to use a curved surface state corresponding to the substrate. Platform. In addition, when the substrate is thick, the substrate may not be sufficiently bent, and the substrate may not be fixed to the top of the platform. Further, in the method of Patent Document 2, when the substrate is thick, the substrate does not sufficiently bend due to the weight of the body.

SUMMARY OF THE INVENTION An object of the present invention is to provide a laser cutting device capable of bending a substrate into a desired shape and fixing it even when a table is not exchanged and the substrate is thick.

The laser cutting device according to the first aspect of the invention is a device for cutting a brittle substrate material along a predetermined line of sculpt of a brittle material substrate, and includes a table on which the brittle material substrate is placed, a substrate means, and a pressing Means, laser irradiation means and cooling means. The substrate holding means presses the both sides of the scribed line to be placed on the brittle material substrate of the table to the table, and holds the brittle material substrate on the table. The pressing means presses a portion of the brittle material substrate including the predetermined line from the opposite side of the laser beam irradiation direction to bend a part of the substrate. The laser irradiation means irradiates the laser beam to the brittle material substrate along the scribed line, and heats the brittle material substrate to less than the melting temperature. The cooling means cools the substrate of the brittle material heated by the laser irradiation means, sprays the cooling medium, and forms a vertical crack along the predetermined line by the thermal stress generated on the substrate of the brittle material.

According to a first aspect of the invention, in the laser cutting device of the second aspect of the invention, the pressing means has a pressing member extending along a predetermined line of scribe. The pressing member is freely movable between a protruding position protruding from the substrate mounting surface of the table toward the laser irradiation surface side of the substrate and a sinking position where the substrate mounting surface sinks toward the opposite side of the laser irradiation surface of the substrate. When moving to the protruding position, a portion of the brittle substrate material including the predetermined line of scribe is bent.

According to a third aspect of the invention, in the apparatus of the second aspect of the invention, the apparatus includes: a first mounting portion, a side supporting a predetermined line of the brittle material substrate; and a second placing portion; The first placing portion is disposed with one space therebetween, and the other side of the scribed line of the brittle material substrate is supported. Then, the pressing member is disposed in a space between the first placing portion and the second placing portion.

According to a fourth aspect of the invention, in the apparatus of the second aspect of the invention, the apparatus includes: a first mounting portion, a side supporting a predetermined line of the brittle material substrate; and a second placing portion; The first placing portion is disposed with a space therebetween, and supports the other side of the scribed line of the brittle material substrate. Then, the pressing member faces the space between the first placing portion and the second placing portion via the brittle material substrate disposed on the table.

In the laser cutting device according to the fifth aspect of the invention, the pressing member is configured to protrude from the substrate mounting surface of the table toward the laser irradiation surface side of the substrate. The first protruding position of one amount and the second protruding position that protrudes to the second amount larger than the first amount.

In the laser cutting device according to the sixth aspect of the invention, in the apparatus according to the first to fifth aspects of the invention, the table is provided with a suction fixing means for fixing the brittle material member.

In the laser cutting device according to the present invention, since the substrate is bent by the pressing means while the substrate is held on the table by the substrate holding means, even if the table is not exchanged and the substrate is thick, The substrate can be bent to the desired amount. Then, by irradiating the laser beam to the substrate in a curved state, a deep vertical crack can be formed on the substrate.

(Embodiment 1)

Hereinafter, the laser cutting device according to an embodiment of the present invention will be described, but the present invention is not limited to the embodiments in any way.

Fig. 1 is a view showing a schematic configuration of a laser cutting device according to an embodiment of the present invention. In the laser device of this drawing, a brittle material substrate (hereinafter referred to as a "substrate") 50 is placed and fixed on the stage 11.

The table 11 has two left and right mounting portions 11a and 11b, and the first mounting portion 11a is provided to be freely movable in the left-right direction. Further, a plurality of intake holes (suction fixing means) 14 are formed on the surfaces of the placing portions 11a and 11b, and the plurality of suction holes 14 are connected to the vacuum pump P. The substrate 50 is suction-fixed to the table 11 by driving the vacuum pump P to attract air. In the central portion of the table 11, that is, between the first placing portion 11a and the second placing portion 11b, the long rod-shaped member (pressing member) 12 is disposed in the vertical direction (front-rear direction) with respect to the paper surface. The position protruding from the table 11 and the position sunk on the table 11 are freely movable. When the rod-shaped member 12 is moved from the work table 11 to the protruding position, the laser beam LB of the substrate 50 is curved so as to be convex. This will be detailed later.

A support table 31 is provided above the table 11 so as to be separated from and opposed to the table 11. The support table 31 is provided in the front-rear direction, and is provided with a cutter wheel (not shown) for forming a trigger crack on the surface of the substrate 50, an opening for irradiating the laser beam LB to the substrate 50, and A nozzle 37 (shown in Fig. 4) for cooling the surface of the substrate 50.

The cutter wheel train can be raised and lowered between the position where it is pressed against the substrate 50 and the non-contact position, and is lowered to the position of the crimp substrate 50 only when the trigger crack which is the starting point of the score line is formed. In order to suppress the occurrence of cracks in the unpredictable direction by the trigger crack, it is preferable to form the trigger crack at the inner side of the surface of the substrate 50.

The laser beam LB emitted from the laser output device 34 is reflected downward by a mirror 44, and is transmitted through an opening (not shown) to an opening formed in the support table 31 to be fixed to the table 11. The upper substrate 50.

Further, the cooling nozzle 37 is provided in the vicinity of the opening in which the laser beam LB is emitted from the support table 31. The water system as a cooling medium is ejected toward the substrate 50 by the cooling nozzle 37 together with the air. The position on the substrate 50 ejected by the cooling medium is on the scribe line 51 and on the rear side of the irradiation area of the laser beam LB (refer to Fig. 4).

On both sides in the left-right direction of the support table 31, rectangular parallelepiped holding members 13a and 13b which are elongated in the front-rear direction are provided. The holding members 13a and 13b are freely movable in the left-right direction and the vertical direction by a driving means (not shown). When the substrate 50 is fixed to the table 11, as will be described later, the rod-shaped member 12 is pressed as a center. The left and right sides of the substrate 50.

A pair of charge coupled devices (CCD) cameras 38, 39 are disposed above the table 11 to identify alignment marks pre-printed on the substrate 50. By the CCD cameras 38 and 39, the position is corrected so that the predetermined line 51 of the substrate 50 (shown in FIG. 4) and the rod-shaped member 12 are overlapped in plan view. Specifically, the positional deviation of the substrate 50 at the time of mounting is detected by the CCD cameras 38 and 39. For example, when the substrate 50 is offset by the angle θ, the table 11 is rotated by -θ, and when the substrate 50 is shifted by Y, The table 11 moves up to -Y.

Fig. 2 and Fig. 3 are views showing a state in which the substrate 50 is cut by using the cutting device having such a configuration. In addition, the occlusion fixing means, the laser beam irradiation means, and the cooling means for absorbing and fixing the substrate 50 to the table 11 are omitted in order to simplify the drawing.

First, the substrate 50 is placed on the table 11, and the vacuum pump P (shown in FIG. 1) is driven, and the substrate 50 is sucked and fixed by the suction hole 14 (shown in FIG. 1). Taiwan 11. Then, the alignment marks provided on the substrate 50 are taken by the CCD cameras 38, 39, and the table 11 is moved based on the photographing data so that the planned line 51 of the substrate 50 (shown in Fig. 4) is The rod-shaped member 12 is considered to be overlapped in plan view, and the substrate 50 is positioned at a predetermined position (Fig. 2(a)).

Next, the holding members 13a and 13b are moved to the center portion, and then lowered, and the substrate 50 is pressed and fixed to the table 11 (Fig. (b)). The degree of pressing and fixing of the substrate 50 by the holding members 13a and 13b is preferably controlled so as to be a predetermined pressing force by sensor detection. Further, the position at which the holding members 13a and 13b are fixed to the substrate 50 can be appropriately determined depending on the material and thickness of the substrate 50, and it is preferable to set the substrate 50 when the substrate 50 is bent by the protrusion of the rod-shaped member 12. The radius of curvature is 4000 mm or less. Therefore, when the amount of protrusion of the rod-shaped member 12 is in the range of 5 mm or less, the distance L from the rod-shaped member 12 to the holding members 13a and 13b is preferably set to 100 mm or more and 300 mm or less. Further, it is preferable that the holding members 13a and 13b are integrally pressed in the front-rear direction of the substrate 50, but the substrate 50 may be pressed at a predetermined interval in the front-rear direction.

Then, the rod-shaped member 12 is displaced to the first protruding position projected by the table 11. Thereby, the substrate 50 is bent (the same as (c)). In view of the amount of protrusion of the rod-shaped member 12, as described above, it is preferable to set the radius of curvature of the substrate 50 to 4000 mm or less, and is usually in the range of 0.1 mm to 5 mm.

Next, as described above, a trigger crack is formed on the substrate 50 by the cutter wheel. Then, the laser beam LB is emitted by the laser output device 34 (Fig. (d)). The laser beam LB is irradiated to the surface of the substrate 50 substantially perpendicularly by the reflecting mirror 44 as shown in FIG. Further, water is sprayed from the cooling nozzle 37 as a cooling medium at the same time near the rear end of the laser beam irradiation region. By irradiating the laser beam LB to the substrate 50, the substrate 50 is heated to a temperature lower than the melting temperature. The substrate 50 is intended to thermally expand, but cannot be expanded due to local heating, and compressive stress is generated around the irradiation point. After the heating instant, the surface of the substrate 50 is cooled by water, whereby the substrate 50 is shrunk to generate tensile stress. By the action of the tensile stress, the trigger crack is used as the starting point, and the vertical crack 53 is formed on the substrate 50 along the scribe line 51. Further, in the present device, since the tensile stress due to the bending of the substrate 50 is added due to the surface of the laser beam irradiated on the substrate 50, the vertical crack 53 is formed to be deeper than usual, depending on the case, vertical. The crack 50 will extend to the opposite side of the substrate 50.

Then, the laser beam LB and the cooling nozzle 37 are relatively moved in the front-rear direction along the scribe line 51, so that the vertical crack 53 progresses in the front-rear direction, and the scribe line 52 is formed on the substrate 50.

The laser beam LB used herein is not particularly limited, and may be appropriately determined depending on the material and thickness of the substrate, the depth of the vertical crack to be formed, and the like. In the case where the brittle material substrate is a glass substrate, it is suitable to use a laser beam having a large absorption wavelength of 9 to 11 μm on the surface of the glass substrate. In the case of such a laser beam, a CO ₂ laser can be exemplified. In terms of the shape of the irradiation spot of the laser beam, it is preferable to have an elliptical shape in which the relative movement direction of the laser beam is elongated, and the irradiation length in the relative movement direction is in the range of 10 to 60 mm, and the irradiation width is 1 to 5 mm. The scope is more appropriate.

As the cooling medium ejected from the cooling nozzle 37, water or alcohol or the like can be exemplified. Further, an additive such as a surfactant may be added to a range that does not adversely affect the use of the brittle material substrate after cutting. The amount of the cooling medium to be sprayed is usually about several ml/min. The cooling of the substrate by the cooling medium is preferably a so-called water jet method in which a gas (usually air) is sprayed together with water from the viewpoint of rapidly cooling the substrate heated by the laser beam. . The cooling zone of the cooling medium is preferably a circular or elliptical shape having a long diameter of about 1 to 5 mm. Further, the cooling area is preferably located behind the relative moving direction of the heating region caused by the laser beam, and is formed such that the distance between the cooling region and the center point of the heating region is about several mm to several tens of mm.

The relative movement speed of the laser beam LB and the cooling nozzle 37 is not particularly limited, and may be appropriately determined depending on the depth of the vertical crack to be obtained and the like. In general, the slower the relative movement speed, the deeper the vertical crack formed. Generally, the relative moving speed is about several hundred mm/sec.

Next, the rod-shaped member 12 is further protruded to the second protruding position (Fig. 3(e)). Thereby, the vertical crack 53 formed on the substrate 50 extends to the opposite surface of the substrate 50 side to cut the substrate 50. Furthermore, in the previous step of forming the vertical cracks 53 by the irradiation of the laser beam LB, the vertical cracks 53 have been extended to the opposite side of the substrate 50, and the steps shown in this figure are not required. The amount of protrusion of the rod-shaped member 12 is not particularly limited as long as the vertical crack 53 can progress to the opposite side of the substrate 50, and it is usually sufficient to have a protrusion amount of about 0.1 mm to 1 mm from the first projection position. Further, when the rod-shaped member 12 is displaced from the first protruding position to the second protruding position, both ends of the rod-shaped member 12 in the rear direction can be simultaneously protruded, and as shown in FIG. One end side of the rod-shaped member 12 in the front-rear direction first protrudes, and the other end side is delayed.

When the cutting of the substrate 50 is completed, the holding member 13a of one of the holding members 13a is lifted, and the pressing of the substrate 50a is released, and the first placing portion 11a moves in the direction away from the rod-shaped member 12 together with the substrate 50a (Fig. 3(f)). . Thereby, the substrates 50a and 50b which are cut into two are separated, and the occurrence of a defect such as a cut surface is prevented. Next, the rod-shaped member 12 is moved from the second protruding position toward the sinking position (Fig. (g)). Furthermore, the steps shown in Fig. 3(f) and the same figure (g) can also be performed simultaneously.

Then, the suction fixing of the first placing portion 11a is released, and the substrate 50a is moved to the next step (Fig. (h)). Then, the holding member 13b is lifted to release the pressing of the substrate 50b, and the suction fixing of the second placing portion 11b is released. Then, the substrate 50b is moved over the rod-like member 12 to a predetermined distance, and the above-described series of cuts are repeated.

The brittle substrate material 50 as the laser cutting device according to the present invention is not particularly limited, and examples thereof include conventionally known brittle material substrates such as glass, ceramic, enamel, and sapphire. The present invention is particularly useful for cutting of a tempered glass substrate such as chemically strengthened glass and air-cooled tempered glass having large surface compressive stress and difficulty in scribing. In addition, the thickness of the brittle material substrate 50 that can be cut by the laser cutting device of the present invention differs depending on the material of the brittle material substrate 50, etc., but the brittle material substrate 50 is a glass substrate. A thickness of about 2 mm is achieved.

Fig. 6 is a view showing another embodiment of the laser cutting device relating to the present invention. The laser cutting device shown in this figure is different from the device of the above-described embodiment in that the rod member 12 is pressed against the surface of the substrate 50 which is pressed by the surfaces of the holding members 13a and 13b. And the point at which the laser beam LB is illuminated by the table side of the substrate 50. Hereinafter, the cutting procedure of the substrate 50 using the apparatus will be mainly described in terms of differences from the apparatus of the above-described embodiment.

First, the substrate 50 is suction-fixed to the table 50 (Fig. 6(a)). Then, the holding members 13a and 13b are moved, and the both sides of the substrate 50 are pressed and fixed by the holding members 13a and 13b around the rod-shaped member 12 (Fig. (b)). Next, the rod-shaped member 12 is lowered, and the substrate 50 is bent (the same as (c)). The amount of protrusion of the rod-shaped member 12 which is downward from the surface of the table 11 is also exemplified herein.

Next, as described above, a trigger crack is formed on the substrate 50 by the cutter wheel. Then, the laser beam LB is emitted by the laser output device 34 (Fig. (d)).

Further, near the rear end of the laser beam irradiation region, water is ejected as a cooling medium by the cooling nozzle 37 (shown in FIG. 4) along the scribe line 51 (shown in FIG. 4) on the substrate 50. A vertical crack is formed. In the apparatus of this embodiment, since the tensile stress caused by the bending of the substrate 50 is also added to the laser beam irradiation surface side of the substrate 50, the vertical crack 53 is formed to be deeper than usual. Hereinafter, the same processing as that shown in Fig. 3 is performed in the apparatus of this embodiment.

(industrial availability)

According to the laser cutting device of the present invention, since the substrate is bent after the substrate is held on the stage, the substrate can be bent into a desired shape even when the substrate is not exchanged and the substrate is thick. It is then useful to form a deep vertical crack on the substrate by irradiating the substrate in a bent state with a laser beam.

11. . . Workbench

11a. . . First placing unit

11b. . . Second placement unit

12. . . Pressing member

13a, 13b. . . Holding member

14. . . Suction hole

31. . . Support desk

34. . . Laser output device

37. . . Cooling nozzle

38, 39. . . CCD camera

44. . . Reflective lens

50. . . Brittle material substrate

51. . . Scribe line

52. . . Scribing

53. . . Vertical crack

LB. . . Laser beam

P. . . Vacuum pump

Fig. 1 is a schematic explanatory view showing an embodiment of a laser cutting device according to the present invention.

Fig. 2 (a) to (d) are process diagrams showing a case where the substrate is cut by using the laser cutting device of Fig. 1.

Fig. 3 (e) to (h) are process diagrams showing a case where the substrate is cut by using the laser cutting device of Fig. 1.

Fig. 4 is a perspective view showing the operational state of the laser scribing.

Fig. 5 (a) to (c) are explanatory views of a movement state when the rod-shaped member is moved from the first protruding position to the second protruding position.

Fig. 6 (a) to (d) are process diagrams showing a case where another laser cutting device according to the present invention is used to cut a substrate.

11. . . Workbench

11a. . . First placing unit

11b. . . Second placement unit

12. . . Pressing member

13a, 13b. . . Holding member

50. . . Brittle material substrate

53. . . Vertical crack

LB. . . Laser beam

Claims (6)

A laser cutting device that illuminates a laser beam along a predetermined line of sculpt of a brittle material substrate to cut the brittle material substrate, the laser cutting device comprising: a table, a substrate for placing a brittle material; and a substrate holding means Pressing the two sides of the scribed line of the brittle material substrate placed on the table to the table, and fixing the brittle material substrate to the table; and pressing means for the opposite side from the direction of the laser beam irradiation Pressing a portion of the substrate of the brittle material including the predetermined line to be scribed to bend a portion of the substrate; and the laser irradiation means irradiating the laser beam to the substrate of the brittle material along the line of the scribe line to heat the substrate of the brittle material to no And a cooling means for cooling the substrate of the brittle material heated by the laser irradiation means, spraying the cooling medium to cool it, and predetermining along the scribe by thermal stress generated on the substrate of the brittle material The line forms a vertical crack; and the aforementioned base centered on the pressing means by the above-described table and the substrate holding means To be fixed on both sides of the state, the pressing means projecting from the mounting face above or below the table of the substrate, whereby the bent portion of the substrate. The laser cutting device of claim 1, wherein the pressing means has a line extending along the predetermined line of scoring a pressing member that protrudes from a substrate mounting surface of the table toward a laser irradiation surface side of the substrate and a side opposite to a laser irradiation surface that is sunk by the substrate mounting surface on the substrate The immersed position is free to move between, and when moving to the aforementioned protruding position, a portion of the brittle material substrate including the scribed line is bent. The laser cutting device according to claim 2, wherein the table has a first placing portion that supports one side of a predetermined line of the brittle material substrate; and a second loading portion The first mounting portion is disposed in a space apart from the first mounting portion, and supports the other side of the predetermined line of the brittle material substrate; the pressing member is disposed on the first mounting portion and the second mounting portion The space between. The laser cutting device according to claim 2, wherein the table has a first placing portion that supports one side of a predetermined line of the brittle material substrate; and a second loading portion And disposed in a space apart from the first placing portion, and supports the other side of the scribed line of the brittle material substrate; the pressing member is disposed so as to be interposed between the brittle material substrates placed on the table Relative to the first placement portion and the second portion The space between the placement sections. The laser cutting device according to claim 2, wherein the pressing member is capable of obtaining a first protruding position that protrudes from the substrate mounting surface of the table toward the laser irradiation surface side of the substrate by a first amount. And a second protruding position that protrudes to a second amount larger than the first amount. The laser cutting device according to claim 1, wherein the absorbing means is provided for fixing the brittle material substrate to the workbench.