TW201601890A - Method for splitting brittle substrate - Google Patents

Abstract

A cutting edge (51) is slid across the surface (SF1) of a brittle substrate (4) so as to cause plastic deformation and form a trench line (TL). The step in which said trench line (TL) is formed is performed in such a manner so as to produce a crack-free state in which, directly underneath the trench line (TL), the brittle substrate (4) is connected in a continuous fashion in a direction that intersects the trench line (TL). Next, a film (21) that at least partially covers the trench line (TL) is formed on the surface (SF1) of the brittle substrate (4), and a crack is then made to extend along the trench line (TL), forming a crack line (CL).

Description

Fragmentation method of brittle substrate

The present invention relates to a method for breaking a brittle substrate, and more particularly to a method for breaking a brittle substrate provided with a film.

In the manufacture of an electric device such as a flat display panel or a solar cell panel, it is often necessary to separate a brittle substrate such as a glass substrate. First, a scribe line is formed on the substrate, and then the substrate is separated along the scribe line. The scribing system can be formed by mechanically processing the substrate using a milling cutter. By sliding or rolling on the substrate by the milling cutter, grooves are formed on the substrate by plastic deformation, and vertical cracks are formed directly under the grooves. Thereafter, stress is applied in a so-called breaking process. The crack is continuously moved in the thickness direction by the breaking process, thereby breaking the substrate.

A film is sometimes provided on the brittle substrate that is broken. In this case, the surface of the brittle substrate is scribed together with the film. A method of cutting a color filter substrate for a flat display panel is disclosed in Japanese Laid-Open Patent Publication No. 2000-280234. The color filter substrate is manufactured by an inkjet method and has an ink containing layer and a protective layer provided on a glass substrate. When the film is provided on the substrate as described above, the scribe line tends to be unstable. In order to cope with the problem, according to the technique of the above publication, the scribing conditions are changed in the formation of the scribing.

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2000-280234

Although attempts have been made to improve the technique of the above-mentioned publication, it is still difficult to stably form a scribing system on a brittle substrate provided with a film. The reason for this is considered to be that it is difficult to optimize the scribing conditions for both the material of the film and the material of the brittle substrate. If the formation of the scribe line is unstable, the division of the substrate using the same is also unstable.

The present invention has been made to solve the above problems, and an object thereof is to provide a method for breaking a brittle substrate in which a brittle substrate having a film is stably separated.

The breaking method of the brittle substrate of the present invention comprises the steps of: preparing a brittle substrate having a surface and having a thickness direction perpendicular to the surface; pressing the blade edge against the surface of the brittle substrate; and pressing the pressing step The blade edge slides on the surface of the brittle substrate to thereby plastically deform the surface of the brittle substrate to form a groove line having a groove shape. The step of forming the trench line may be performed in a state in which the brittle substrate is continuously connected in a direction intersecting the trench line directly under the trench line, that is, in a crack-free state. Further, the breaking method of the brittle substrate of the present invention further includes the step of forming a film at least partially covering the groove line on the surface of the brittle substrate after the step of forming the groove line; After the step, the crack line is formed by stretching the crack of the brittle substrate along the groove line in the thickness direction. The fragile substrate is continuously connected to the brittle substrate in a direction crossing the groove line by the crack line directly under the groove line. The breaking method of the brittle substrate of the present invention further includes the step of dividing the brittle substrate along the crack line.

In addition, the above-mentioned "pressing the blade tip against the surface" means that the blade edge is pressed to any position of the "surface". Therefore, the blade edge may be pressed against the edge of the "surface".

According to the present invention, as a line defining the position of the brittle substrate, a groove line having no crack directly under it is formed. The crack line used as a direct trigger for breaking is tied to Formed after forming a groove line. Thereby, the brittle substrate before the formation of the groove line and before the formation of the crack line not only defines the position to be broken by the groove line, but also does not easily form a state in which the crack line is not formed. In this state, a film is formed on the groove line, that is, on the line defining the position of the brittle substrate. Thereafter, the crack line used as a direct trigger for the breaking is formed by stretching the crack in a self-aligned manner along the groove line. Thereby, the crack line can be stably formed almost without being affected by the presence of the film. Therefore, the brittle substrate can be stably separated.

4‧‧‧Glass substrate (brittle substrate)

4a‧‧‧Substrate film

4b‧‧‧Substrate film

11‧‧‧ components

21‧‧‧ film

Section 21a‧‧‧

Section 21b‧‧‧

22‧‧‧ film

Section 22a‧‧‧

Section 22b‧‧‧

50‧‧‧ cutting instruments

50p‧‧‧ cutting appliances

51‧‧‧Tool tip

51P‧‧‧ cutting edge

51v‧‧‧ pointed

52‧‧‧Knife

52p‧‧‧holder

AL‧‧‧Auxiliary line

AX‧‧‧ axis direction

CL‧‧‧ crack line

DA‧‧‧ directions

DB‧‧‧ direction

DC‧‧ direction

DT‧‧‧ thickness direction

ED1‧‧‧ side (1st side)

ED2‧‧‧ side (2nd side)

ED3‧‧‧ side

ED4‧‧‧ side

FB‧‧‧ external force

HL‧‧ cut

IB-IB‧‧‧ line

IIB-IIB‧‧‧ line

Line IIIB-IIIB‧‧

IVB-IVB‧‧‧ line

IXB-IXB‧‧‧ line

N1‧‧‧ position (1st position)

N2‧‧‧ position (2nd position)

N3‧‧‧ position

N4‧‧‧ position

PP‧‧‧Protruding

PPv‧‧‧Protruding

PS‧‧‧ side

PSv‧‧‧ side

SC‧‧‧Conical surface

SD1‧‧‧ top surface (1st side)

SD2‧‧‧ side (2nd side)

SD3‧‧‧ side (3rd side)

SF1‧‧‧ upper surface (surface)

SF2‧‧‧ lower surface

SL‧‧‧

S10~S60‧‧‧Steps

TL‧‧‧ trench line

UL‧‧‧ incision

VB-VB‧‧‧ line

VIB-VIB‧‧‧ line

XEt‧‧‧ end

XEs‧‧ End

XB-XB‧‧‧ line

XIB-XIB‧‧‧ line

XIIB-XIIB‧‧‧ line

XIIIB-XIIIB‧‧‧ line

XIVB-XIVB‧‧‧ line

XIXB-XIXB‧‧‧ line

XVB-XVB‧‧‧ line

XVIB-XVIB‧‧‧ line

XVIIB-XVIIB‧‧‧ line

XVIIIB-XVIIIB‧‧‧ line

XXB‧‧‧ arrow

XXXIIIB‧‧‧ arrow

Fig. 1 is a schematic plan view (A) showing a method of dividing a brittle substrate according to Embodiment 1 of the present invention, and a schematic cross-sectional view (B) along line IB-IB.

Fig. 2 is a schematic plan view (A) showing a breaking method of the brittle substrate according to the first embodiment of the present invention, and a schematic cross-sectional view (B) along the line IIB-IIB.

Fig. 3 is a schematic plan view (A) showing a method of dividing a brittle substrate according to the first embodiment of the present invention, and a schematic cross-sectional view (B) along the line IIIB-IIIB.

Fig. 4 is a schematic plan view (A) showing a breaking method of the brittle substrate according to the first embodiment of the present invention, and a schematic cross-sectional view (B) along the line IVB-IVB.

Fig. 5 is a schematic plan view (A) showing a breaking method of the brittle substrate according to the first embodiment of the present invention, and a schematic cross-sectional view (B) along the line VB-VB.

Fig. 6 is a schematic plan view (A) showing a method of dividing a brittle substrate according to the first embodiment of the present invention, and a schematic cross-sectional view (B) taken along line VIB-VIB.

Fig. 7 is a cross-sectional view (A) showing a configuration of a groove line formed in the breaking method of the brittle substrate according to the first embodiment of the present invention, and a cross-sectional view (B) schematically showing the configuration of the crack line.

Fig. 8 is a flow chart schematically showing the configuration of a breaking method of the brittle substrate according to the first embodiment of the present invention.

Fig. 9 is a plan view (A) showing a method of dividing a brittle substrate of a comparative example, and a cross-sectional view (B) along a line IXB-IXB thereof.

Fig. 10 is a plan view (A) showing a method of breaking a brittle substrate of a comparative example, and a cross-sectional view (B) along a line XB-XB thereof.

Fig. 11 is a schematic plan view (A) showing a method of dividing a brittle substrate according to a second embodiment of the present invention, and a schematic cross-sectional view (B) along the line XIB-XIB.

Fig. 12 is a schematic plan view (A) showing a method of dividing a brittle substrate according to a second embodiment of the present invention, and a schematic cross-sectional view (B) along the line XIIB-XIIB.

Fig. 13 is a schematic plan view (A) showing a method of dividing a brittle substrate according to a second embodiment of the present invention, and a schematic cross-sectional view (B) along the line XIIIB-XIIIB.

Fig. 14 is a schematic plan view (A) showing a method of dividing a brittle substrate according to a second embodiment of the present invention, and a schematic cross-sectional view (B) along the line XIVB-XIVB.

Fig. 15 is a schematic plan view (A) showing a method of dividing a brittle substrate according to a second embodiment of the present invention, and a schematic cross-sectional view (B) along the line XVB-XVB.

Fig. 16 is a plan view (A) showing a method of breaking a brittle substrate of a comparative example, and a sectional view (B) along the line XVIB-XVIB.

Fig. 17 is a plan view (A) showing a method of breaking a brittle substrate of a comparative example, and a sectional view (B) along the line XVIIB-XVIIB.

Fig. 18 is a schematic plan view (A) showing a method of dividing a brittle substrate according to a modification of the second embodiment of the present invention, and a schematic cross-sectional view (B) along the line XVIIIB-XVIIIB.

Fig. 19 is a schematic plan view (A) showing a method of dividing a brittle substrate according to a modification of the second embodiment of the present invention, and a schematic cross-sectional view (B) along the line XIXB-XIXB.

Fig. 20 is a side view (A) schematically showing the configuration of an apparatus used in the breaking method of the brittle substrate according to the third embodiment of the present invention, and schematically showing the apparatus having the arrow XXB in Fig. 20(A). Top view of the configuration of the tip (B).

21(A) and 21(B) are plan views schematically showing a method of dividing a brittle substrate according to a third embodiment of the present invention.

22(A) and 22(B) are diagrams schematically showing the brittleness of the first modification of the third embodiment of the present invention. A top view of the method of breaking the substrate.

Fig. 23 is a plan view schematically showing a method of dividing a brittle substrate according to a second modification of the third embodiment of the present invention.

Fig. 24 is a plan view schematically showing a method of dividing a brittle substrate according to a third modification of the third embodiment of the present invention.

Fig. 25 is a plan view schematically showing a first step of the breaking method of the brittle substrate according to the fourth embodiment of the present invention.

Fig. 26 is a plan view schematically showing a second step of the breaking method of the brittle substrate according to the fourth embodiment of the present invention.

Fig. 27 is a plan view schematically showing a third step of the breaking method of the brittle substrate according to the fourth embodiment of the present invention.

28 (A) and (B) are plan views schematically showing a method of dividing a brittle substrate according to a first modification of the fourth embodiment of the present invention.

FIG. 29 is a plan view schematically showing a method of dividing a brittle substrate according to a second modification of the fourth embodiment of the present invention.

30(A) and (B) are plan views schematically showing a method of dividing a brittle substrate according to a fifth embodiment of the present invention.

31(A) and (B) are plan views schematically showing a method of dividing a brittle substrate according to a sixth embodiment of the present invention.

Fig. 32 is a plan view schematically showing a method of dividing a brittle substrate according to a modification of the sixth embodiment of the present invention.

Figure 33 is a side view (A) schematically showing the configuration of an apparatus used in the breaking method of the brittle substrate according to the seventh embodiment of the present invention, and schematically showing the above-mentioned apparatus in the viewpoint of the arrow XXXIIIB of Figure 33 (A). Top view of the configuration of the tip (B).

Hereinafter, embodiments of the present invention will be described based on the drawings. In addition, the following figure The same or corresponding portions in the formula are denoted by the same reference numerals and the description thereof is not repeated.

(Embodiment 1)

The method of breaking the brittle substrate of the present embodiment will be described below.

Referring to Fig. 1 (A) and (B), first, a glass substrate 4 (brittle substrate) is prepared (Fig. 4: step S10). The glass substrate 4 has an upper surface SF1 (surface) and a surface SF2 opposite thereto. The glass substrate 4 has a thickness direction DT perpendicular to the upper surface SF1. Further, a cutting instrument 50 having a blade edge 51 and a shank 52 is prepared. The blade tip 51 is held by being fixed to the shank 52 as its holder.

Next, the blade edge 51 is pressed against the upper surface SF1 of the glass substrate 4 (FIG. 8: Step S20). Next, the pressed blade tip 51 is slid on the upper surface SF1 of the glass substrate 4 (see an arrow in FIG. 1(A)).

Referring to Figs. 2(A) and (B), plastic deformation occurs on the upper surface SF1 of the glass substrate 4 by the above-described sliding of the blade edge 51. Thereby, a groove line TL having a groove shape is formed on the upper surface SF1 (FIG. 8: step S30). Referring to FIG. 7(A), the process of forming the trench line TL may be performed by directly extending the glass substrate 4 and the trench line TL directly under the trench line TL (the horizontal direction of FIG. 2(A)). The state in which the cross direction is continuously connected to the DC is a crack-free state. In the crack-free state, although the groove line TL is formed by plastic deformation, a crack along it is not formed. Therefore, even if a force such as a bending moment is simply applied to the glass substrate 4 as in the previous breaking step, the breaking along the groove line TL is not easily caused. Therefore, the breaking process along the groove line TL is not performed in the state without the crack line. In order to obtain a crack-free state, the load applied to the cutting edge 51 is set to such an extent that cracks are not generated and are large to the extent of plastic deformation.

The crack-free state must be maintained for a necessary period of time. To maintain the crack-free state, it is only necessary to avoid the operation of applying excessive stress to the glass substrate 4 in the trench line TL, for example, applying a large external stress which may cause damage to the substrate or heating with a large temperature change. .

Referring to FIGS. 3(A) and (B), the crack-free state is maintained, and the film 21 is formed on the surface SF1 of the glass substrate 4 (FIG. 8: Step S40). The formation of the film 21 is performed in such a manner as to at least partially cover the groove line TL. The film 21 can be made of an inorganic material, in particular also of metal.

Referring to FIGS. 4(A) and (B), the glass substrate 4 is processed by maintaining the crack-free state. For example, the member 11 is provided on the film 21. The member 11 can also be spaced apart from the groove line TL. The member 11 has a portion that is separated by a groove line TL. Further, a member (not shown) may be provided on the lower surface SF2. The step of providing the member can be performed, for example, by joining a member prepared in advance or depositing a raw material.

5 (A) and (B), after the film 21 is formed as described above, the crack of the glass substrate 4 is stretched in the thickness direction DT along the groove line TL. Thereby, the crack line CL is formed in self-alignment with respect to the groove line TL (FIG. 8: Step S50). Referring to FIG. 7(B), the crack line CL is continuous under the groove line TL, and the glass substrate 4 is continuous in the direction DC which intersects with the extending direction of the groove line TL (the lateral direction of FIG. 5(A)). Connected disconnected. Here, the term "continuously connected", in other words, is not connected by a crack. Further, in a state of being continuously connected and disconnected as described above, one portion of the glass substrate 4 may be in contact with each other via a crack of the crack line CL.

The formation of the crack line CL is started by, for example, applying an internal stress-strain-like stress in the vicinity of the groove line TL to the glass substrate 4 by the end portion XEx or XEt (Fig. 4(A)) of the groove line TL. The application of the stress is performed, for example, by pressing the blade tip against the formed groove line TL to generate external stress, or by heating by irradiation of laser light or the like.

6(A) and (B), the glass substrate 4 is divided into the substrate sheets 4a and 4b along the crack line CL (FIG. 8: Step S60). That is, a so-called breaking process is performed. The breaking step can be performed, for example, by applying an external force FB to the glass substrate 4 (Fig. 5(B)). The film 21 is separated into the portions 21a and 21b together with the glass substrate 4 by the tension applied to the film 21 when the glass substrate 4 is divided. Thereby, the substrate piece 4a provided with the portion 21a of the film 21 and the substrate piece 4b provided with the portion 21b of the film 21 are obtained.

Next, the method of dividing the glass substrate 4 of the comparative example will be described below. In the present comparative example, a general scribing step and a breaking step were performed.

Referring to FIGS. 9(A) and (B), in the comparative example, the groove line TL is not formed, and the film 21 and the member 11 are provided on the glass substrate 4. Next, the blade edge 51 is pressed against the upper surface SF1 of the glass substrate 4. Next, the pressed blade edge 51 is slid over the upper surface SF1 on which the film 21 is provided (refer to the arrow in FIG. 9(A)).

Referring to Figs. 10(A) and (B), the film 21 is divided into portions 21a and 21b by the above sliding of the blade edge 51. At the same time, a scribe line SL having a crack is formed on the upper surface SF1 of the glass substrate 4. Next, the glass substrate 4 is separated along the scribe line SL by a breaking process.

In the comparative example, the upper surface SF1 of the glass substrate 4 is scribed together with the film 21. In such a case, the formation of the scribe line SL used as a direct trigger for breaking the glass substrate 4 tends to be unstable. As a result, the breaking of the glass substrate 4 is also liable to become unstable. Moreover, the quality of the cut surface of the film 21 is liable to lower.

On the other hand, according to the present embodiment, as a line defining the position at which the glass substrate 4 is cut, a groove line TL having no crack directly below is formed. The crack line CL used as a direct trigger for the breaking is formed after the groove line TL is formed. Thereby, the glass substrate 4 before the formation of the trench line TL and before the formation of the crack line CL not only defines the position of the glass substrate 4 by the groove line TL, but also does not easily form a crack because the crack line CL has not been formed. The state of the break. In this state, the film 21 is formed on the groove line TL, that is, the line defining the position at which the glass substrate 4 is separated. Thereafter, the crack line CL used as a direct trigger of the breaking is formed by self-aligning the crack along the groove line TL. Thereby, the crack line CL can be stably formed without being affected by the presence of the film 21. Therefore, the glass substrate 4 can be stably separated.

The step of forming the crack line CL of the present embodiment is substantially different from the so-called breaking step. The breaking process is such that the formed crack is further extended in the thickness direction to completely separate the substrate. On the other hand, the step of forming the crack line CL is changed from the crack-free state obtained by forming the groove line TL to the state in which the crack is present. The change is considered to be open Produced by the internal stress of the crack-free state. The plastic deformation at the time of forming the groove line TL and the magnitude or directivity of the internal stress generated by forming the groove line TL are both rolling using a rotary blade and using a blade tip sliding as in the present embodiment. The situation is different. When the blade tip is used for sliding, cracks are likely to occur under a wide scribing condition. Further, opening the internal stress requires a number of opportunities, and it is considered that the crack on the groove line TL is generated by the application of stress from the outside as described above. Details of a preferred method of forming the groove line TL and the crack line CL will be described in the following embodiments 3 to 7.

Further, according to the present embodiment, when the glass substrate 4 is separated, the film 21 is separated together with the glass substrate 4. Thereby, the film 21 can be separated by the breaking of the glass substrate 4. Therefore, it is not necessary to cut the film 21 using a cutting instrument. Therefore, it is possible to avoid the generation of chips due to the cutting of the film 21. Moreover, the wear of the blade edge 51 can be suppressed compared with the case where the scribe film 21 and the glass are simultaneously with the blade edge 51.

In the case where the film 21 is made of an inorganic material, a material which is difficult to break as a synthetic resin is not used for the film 21. Thereby, the breaking of the film 21 accompanying the division of the glass substrate 4 can be surely produced. Moreover, the generation of chips of inorganic materials can be avoided. Moreover, abrasion caused when the blade tip 51 is scribed with the inorganic material can be avoided. In particular, in the case where the film 21 is made of a metal, a material which is difficult to break as a synthetic resin is not used for the film 21. Thereby, the breaking of the film 21 accompanying the division of the glass substrate 4 can be surely produced. Also, metal chips can be avoided. Moreover, wear caused when the blade tip 51 is scribed to the metal can be avoided.

(Embodiment 2)

In the breaking method of the brittle substrate of the present embodiment, first, the same steps as in the first embodiment are carried out until the steps of FIGS. 2(A) and (B).

Referring to FIGS. 11(A) and (B), the film-free state is maintained on the surface SF1 of the glass substrate 4 (FIG. 8: Step S40). The formation of the film 22 is performed in such a manner as to at least partially cover the trench line TL. The film 22 can be made of synthetic resin.

Referring to Fig. 12 (A) and (B), next, a cutting instrument 50p having a blade edge 51p and a shank 52p is prepared. The blade tip 51p is held by being fixed to the shank 52p as its holder. The cutting tool 50p is preferably a processor that is more suitable for the film 22 than the cutting tool 50.

Further, referring to FIGS. 13(A) and (B), the slit HL is cut into the film 22 along the groove line TL (see the arrow of FIG. 12(A)) using the blade edge 51p. The slit HL is formed by completely cutting the film 22 in the thickness direction DT of the film 22. In other words, the slit HL penetrates the film 22 in the thickness direction DT. The portions 22a and 22b are separated by cutting into the slit HL film 22.

Referring to Fig. 14 (A) and (B), the crack line CL is formed by the same method as in the first embodiment (Figs. 5 (A) and (B)).

15 (A) and (B), the glass substrate 4 is divided into the substrate sheets 4a and 4b along the crack line CL (FIG. 8: Step S60). That is, a so-called breaking process is performed. The breaking step is the same as in the first embodiment (Fig. 5(B)), and can be performed by applying an external force FB to the glass substrate 4. By dividing the glass substrate 4, the substrate piece 4a provided with the portion 22a of the film 22 and the substrate piece 4b provided to the portion 22b of the film 22 are obtained.

Next, the method of dividing the glass substrate 4 of the comparative example will be described below. In the present comparative example, a general scribing step and a breaking step were performed.

Referring to FIGS. 16(A) and 16(B), in the comparative example, the trench line TL is not formed, and the film 22 is provided on the glass substrate 4. Next, the blade edge 51 is pressed against the upper surface SF1 of the glass substrate 4. Next, the pressed blade edge 51 is slid over the upper surface SF1 on which the film 22 is provided (refer to the arrow in FIG. 16(A)).

Referring to Figs. 17(A) and (B), the film 22 is divided into portions 22a and 22b by the above sliding of the blade edge 51. At the same time, a scribe line SL having a crack is formed on the upper surface SF1 of the glass substrate 4. Next, the substrate 4 is separated along the scribe line SL by a breaking process.

In the present comparative example, the upper surface SF1 of the glass substrate 4 is scribed together with the film 22. In such a case, the formation of the scribe line SL used as a direct trigger for breaking the glass substrate 4 tends to be unstable. As a result, the breaking of the glass substrate 4 is also liable to become unstable.

In particular, in the case where the film 22 is made of a synthetic resin, it is necessary to simultaneously form the cut film 22 and form the scribe line SL on the glass substrate 4. However, in the formation of the cut of the film 22 and the formation of the scribe line SL, generally, the optimum tool tip 51 and its use conditions are considerably different. Therefore, it is difficult to optimize the blade edge 51 and its use conditions, and as a result, the formation of the scribe line SL is particularly likely to become unstable.

On the other hand, according to the present embodiment, as in the first embodiment, the crack line CL can be stably formed without being affected by the presence of the film 22. Therefore, the glass substrate 4 can be stably separated.

Further, before the crack line CL is formed, the slit is cut into the film 22 along the groove line TL. Thereby, the film 22 is surely divided. The step of cutting the slit into the film 22 is performed by completely cutting the film 22 in the thickness direction DT of the film 22. Thereby, the film 22 is further divided more reliably.

In particular, in the case where the film 22 is made of a synthetic resin, since the toughness of the film 22 is high, it is difficult to obtain the breaking depending on the tension application as in the first embodiment. Even in this case, the film 22 can be separated by using the slit. Further, the film 22 of the synthetic resin is less likely to generate chips. Further, the synthetic resin film 22 makes the blade edge 51p less likely to be worn.

Further, instead of the cutting tool 50p (Fig. 12(B)) which is particularly suitable for the film 22, the cutting tool 50 (Fig. 1(B)) can be used, and in this case, a common cutting tool can be used in two processes.

Next, a first modification of the embodiment will be described. The film 22 is completely cut in the thickness direction DT in the above-described FIGS. 13(A) and (B), but in the present modification, as shown in FIGS. 18(A) and (B), the thickness of the film 22 is shown. The film 22 is partially cut in the direction DT. In other words, incomplete cutting is performed in the thickness direction DT. Thereby, the slit 22 which does not penetrate the film 22 is cut into the film 22.

Referring to Figs. 19(A) and (B), a crack line CL is formed next. The film 22 is not completely broken at this point in time. The incomplete slit is changed to a complete slit in the thickness direction DT by the tension applied to the film 22 when the glass substrate 4 is divided, and the film 22 is completely broken. According to the present modification, the glass substrate 4 is prevented from being damaged when the film 22 is cut.

Next, a second modification of the embodiment will be described. In the present variation, the film 22 is partially cut along the groove line TL. In other words, along the groove line TL, a portion where the slit is not formed is formed in one portion of the film 22. The slit may be intermittently formed along the groove line TL in the entirety or at one location. The incision system may be either in the thickness direction or incomplete. Thereby, the slit HL (refer to FIG. 13) or the slit UL (refer to FIG. 18) is cut along a portion of the groove line TL of the film 22.

Next, a crack line CL is formed. The film 22 is not completely broken at this point in time. The complete division of the film 22 is caused by the tension applied to the film 22 when the glass substrate 4 is broken, and the incomplete slit is continuously expanded along the groove line TL. According to the type of the film, if the film is easily cracked in a specific direction, according to the present modification, the film 22 can be easily cut by breaking the film 22 at the time of breaking, and the glass substrate 4 can be damaged. Hey.

(Embodiment 3)

First, the tip of the cutting method used in the brittle substrate of the present embodiment will be described below.

Referring to FIGS. 20(A) and (B), the cutting edge 51 is provided with a top surface SD1 (first surface) and a plurality of surfaces surrounding the top surface SD1. The plurality of faces include a side surface SD2 (second surface) and a side surface SD3 (third surface). The top surface SD1, the side surfaces SD2, and the SD3 (the first to third surfaces) are oriented in mutually different directions and adjacent to each other. The blade tip 51 has a vertex at which the top surface SD1, the side surfaces SD2, and SD3 meet, and the apex constitutes the protrusion PP of the blade edge 51. Further, the side faces SD2 and SD3 are ridge lines constituting the side portions PS of the blade edge 51. The side portion PS extends linearly from the protrusion portion PP. Further, since the side portion PS is a ridge line as described above, it has a convex shape extending linearly.

The tip 51 is preferably a diamond cutter head. That is, the tip 51 is preferably made of diamond in terms of the point where the hardness and the surface roughness can be reduced. More preferably, the tip 51 is made of single crystal diamond. More preferably, in terms of crystallography, the top surface SD1 is a {001} plane, and the side surfaces SD2 and SD3 are each a {111} plane. In this case, although the side surface SD2 and the side surface SD3 have different orientations, they are crystallographically equivalent to each other.

Further, a non-single crystal diamond may be used, for example, a polycrystalline diamond synthesized by a CVD (Chemical Vapor Deposition) method. Alternatively, the polycrystalline diamond particles obtained by sintering the binder containing no iron group element or the like from the particulate graphite or the non-graphite carbon may be used to bond the sintered diamond by a bonding material such as an iron group element.

The shank 52 extends along the axial direction AX. The blade edge 51 is preferably attached to the shank 52 so as to be substantially along the axial direction AX in the normal direction of the top surface SD1.

In order to form the groove line TL (FIG. 7(A)) using the cutting tool 50, the protrusion PP and the side portion PS of the blade edge 51 are pressed against the thickness direction DT of the glass substrate 4 on the upper surface SF1 of the glass substrate 4. . Next, the blade edge 51 is slid on the upper surface SF1 substantially along the direction in which the side portion PS is projected on the upper surface SF1. Thereby, a groove-like groove line TL having no vertical crack is formed on the upper surface SF1. The groove line TL is generated by plastic deformation of the glass substrate 4, but the glass substrate 4 may be slightly cut at this time. However, since such cutting may produce fine fragments, it is preferably as small as possible.

There are cases where the groove line TL and the crack line CL (Fig. 7(B)) are simultaneously formed by the sliding of the blade edge 51, and the case where only the groove line TL is formed. The crack line CL is a slit extending from the depression of the groove line TL in the thickness direction DT, and extends linearly on the upper surface SF1. According to the method described later, the crack line CL can be formed along the groove line TL.

Next, the method of dividing the glass substrate 4 will be described below.

Referring to Fig. 21(A), in step S10 (Fig. 8), the glass substrate 4 is first prepared. The glass substrate 4 has a flat upper surface SF1. The edge surrounding the upper surface SF1 includes sides ED1 (first side) and side ED2 (second side) facing each other. In the example shown in Fig. 21(A), the edges are rectangular. Therefore, the sides ED1 and ED2 are parallel to each other. Further, in the example shown in Fig. 21(A), the sides ED1 and ED2 are the short sides of the rectangle. Further, the glass substrate 4 has a thickness direction DT perpendicular to the upper surface SF1 (Fig. 20(A)).

Next, in step S20 (FIG. 8), the blade edge 51 is pressed to the position N1 on the upper surface SF1. Details of the position N1 will be described later. The pressing of the blade tip 51 is referred to FIG. 20(A) for the glass substrate 4 The protrusion PP of the blade edge 51 is disposed between the side ED1 and the side portion PS on the upper surface SF1, and the side portion PS of the blade edge 51 is disposed between the protrusion portion PP and the side ED2.

Next, in step S30 (FIG. 8), a plurality of groove lines TL (five lines in the drawing) are formed on the upper surface SF1. The formation of the groove line TL is performed between the position N1 (first position) and the position N3. The position N2 (the second position) is located between the positions N1 and N3. Therefore, the groove line TL is formed between the positions N1 and N2 and between the positions N2 and N3.

The positions N1 and N3 may be located at a distance from the edge of the upper surface SF1 of the glass substrate 4 as shown in Fig. 21(A), or one or both of them may be located at the edge of the upper surface SF1. The groove line TL to be formed has a distance from the edge of the glass substrate 4 in the former case and the edge of the glass substrate 4 in the latter case.

In the positions N1 and N2, the position N1 is closer to the side ED1; and in the positions N1 and N2, the position N2 is closer to the side ED2. Further, in the example shown in FIG. 21(A), the position N1 is closer to the side ED1 in the sides ED1 and ED2, and the position N2 is closer to the side ED2 in the sides ED1 and ED2, but may be the positions N1 and N2. They are all located close to either of the sides ED1 or ED2.

In the case where the groove line TL is formed, in the present embodiment, the blade edge 51 is displaced from the position N1 to the position N2, and is displaced from the position N2 to the position N3. That is, referring to Fig. 20(A), the cutting edge 51 is displaced in the direction DA from the side ED1 toward the side ED2. The direction DA corresponds to a direction in which the axis AX extending from the blade edge 51 is projected on the upper surface SF1. In this case, the blade tip 51 is dragged on the upper surface SF1 by the shank 52.

Next, the crack-free state (Fig. 7(A)) described in the first embodiment is maintained for a desired period of time. In the same period, as the step S40 (Fig. 8), the film 21 (Figs. 3(A) and (B)) is formed in the same manner as in the first embodiment, or the film 22 is formed in the same manner as in the second embodiment (Fig. 11(A) and (B)). In the latter case, in the above-described period, as described in the second embodiment or its modification, the slit is cut into the film 22 along the groove line TL (see the arrow in FIG. 12(A)) (for example, refer to FIG. 13 ( Incision HL) in B).

Referring to FIG. 21(B), in step S50 (FIG. 8), after the trench line TL is formed, by making the glass The crack of the substrate 4 extends along the groove line TL from the position N2 to the position N1 (in the drawing, with reference to the dotted arrow) in the thickness direction DT (Fig. 7(B)) to form the crack line CL. The formation of the crack line CL is started by the intersection of the auxiliary line AL and the groove line TL at the position N2. For this purpose, the auxiliary line AL is formed after the groove line TL is formed. The auxiliary line AL is accompanied by a general scribe line of the crack in the thickness direction DT, and is a strainer that releases the internal stress near the groove line TL. The method of forming the auxiliary line AL is not particularly limited, but as shown in FIG. 21(B), the edge of the upper surface SF1 may be formed as a base point.

Further, it is more difficult to form the crack line CL from the position N2 to the position N3 than in the direction from the position N2 to the position N1. That is, the ease of stretching of the crack line CL has a direction dependency. Therefore, there is a possibility that a crack line CL is formed between the positions N1 and N2 and is not formed between the positions N2 and N3. In the present embodiment, the glass substrate 4 is separated between the positions N1 and N2, and the glass substrate 4 is not separated along the positions N2 and N3. Therefore, it is necessary to form the crack line CL between the position N1 and the position N2. On the other hand, the difficulty in forming the crack line CL between the position N2 and the position N3 is not a problem.

Next, in step S60 (Fig. 8), the glass substrate 4 is separated along the crack line CL. Specifically, the breaking step is carried out. Further, when the crack line CL completely travels in the thickness direction DT when it is formed, the formation of the crack line CL and the breaking of the glass substrate 4 can be simultaneously generated. In this case, the breaking step can be omitted.

The division of the glass substrate 4 is performed by the above.

Next, the first to third modifications of the above-described breaking method will be described below.

Referring to Fig. 22(A), the first variation is a case where the timing of the formation of the crack line CL (Fig. 21(B)) by the intersection of the auxiliary line AL and the groove line TL is insufficient. Referring to Fig. 22(B), the glass substrate 4 is separated along the auxiliary line AL by applying an external force such as a bending moment to the glass substrate 4. Thereby, the crack line CL is started to be formed.

In addition, in FIG. 22(A), the auxiliary line AL is formed on the upper surface SF1 of the glass substrate 4, but the auxiliary line AL for separating the glass substrate 4 may be formed on the lower surface SF2 of the glass substrate 4. on. In this case, the auxiliary line AL and the groove line TL are arranged in a plan view and intersect each other at the position N2, but are not in direct contact with each other.

Further, in the first modification, the strain line CL is started to be formed by separating the glass substrate 4 and releasing the strain of the internal stress in the vicinity of the groove line TL. Therefore, the auxiliary line AL itself may be the crack line CL formed by applying stress to the groove line TL.

Referring to Fig. 23, in the second modification, in step S20 (Fig. 8), the blade edge 51 is pressed against the position N3 on the upper surface SF1 of the glass substrate 4. In step S30 (FIG. 8), when the groove line TL is formed, in the present modification, the blade edge 51 is displaced from the position N3 to the position N2, and further displaced from the position N2 to the position N1. That is, referring to Fig. 20, the blade edge 51 is displaced from the side ED2 toward the side ED1, that is, toward the direction DB. The direction DB corresponds to a direction opposite to a direction in which the axis AX extending from the blade edge 51 is projected on the upper surface SF1. In this case, the cutting edge 51 is advanced on the upper surface SF1 by the shank 52.

Referring to Fig. 24, in the third modification, in step S30 (Fig. 8), when the groove line TL is formed, it is pressed with a larger force at the position N2 than the position N1 of the upper surface SF1 of the glass substrate 4. Tip 51. Specifically, the position N4 is set as the position between the positions N1 and N2, and when the groove line TL forms the arrival position N4, the load of the blade edge 51 is increased. In other words, the load of the groove line TL is increased between the positions N4 and N3 which are the end portions of the groove line TL as compared with the position N1. Thereby, the load other than the end portion can be alleviated, and the crack line CL can be more easily formed from the position N2.

According to the present embodiment, the crack line CL can be formed more reliably from the groove line TL.

Further, in the present embodiment which is different from the fourth embodiment to be described later, the auxiliary line AL is not formed at the time of forming the groove line TL (Fig. 21(A)). Therefore, it is possible to maintain the crack-free state more stably without being affected by the auxiliary line AL. Further, in the case where the stability of the crack-free state is not a problem, the state in which the auxiliary line AL is not formed (Fig. 21 (A)) can be replaced, and the state in Fig. 22 (A) in which the auxiliary line AL is formed is maintained without cracks. status.

(Embodiment 4)

The breaking method of the brittle substrate of the present embodiment will be described below with reference to Figs. 25 to 27 .

Referring to Fig. 25, in the present embodiment, the auxiliary line AL is formed before the groove line TL is formed. The method of forming the auxiliary line AL itself is the same as that of Fig. 21 (B) (Embodiment 3).

Referring to Fig. 26, next to step S20 (Fig. 8), the blade edge 51 is pressed against the upper surface SF1, and then, in step S30 (Fig. 8), the groove line TL is formed. The method of forming the trench line TL itself is the same as that of FIG. 6(A) (Embodiment 3). The auxiliary line AL and the groove line TL cross each other at the position N2. Then, in the same manner as in the third embodiment, as the step S40 (Fig. 8), the film 21 is formed in the same manner as in the first embodiment (Figs. 3(A) and (B)), or the film 22 is formed in the same manner as in the second embodiment (Fig. 11). (A) and (B)). In the latter case, in the above-described period, as described in the second embodiment or its modification, the slit is cut into the film 22 along the groove line TL (see the arrow in FIG. 12(A)) (for example, refer to FIG. 13 ( Incision HL) in B).

Referring to Fig. 27, next, a glass substrate 4 is separated along the auxiliary line AL by applying a general breaking step of generating a force such as a bending moment to the glass substrate 4. Thereby, as the step S50 (FIG. 20), the formation of the crack line CL (FIG. 7(B)) is started (in the drawing, the dotted arrow is referred to). Further, in FIG. 25, the auxiliary line AL is formed on the upper surface SF1 of the glass substrate 4, but the auxiliary line AL for separating the glass substrate 4 may be formed on the lower surface SF2 of the glass substrate 4. In this case, the auxiliary line AL and the groove line TL cross each other at the position N2 in a plan view, but are not in direct contact with each other.

The configuration other than the above is substantially the same as the configuration of the above-described third embodiment.

Referring to Fig. 28(A), in the first modification, the auxiliary line AL is formed on the lower surface SF2 of the glass substrate 4. Next, similarly to FIG. 23 (Embodiment 3), the groove line TL is formed from the position N3 to the position N1. Referring to Fig. 28(B), the glass substrate 4 is separated along the auxiliary line AL by applying an external force such as a bending moment to the glass substrate 4. Thereby, the formation of the crack line CL is started (in the drawing, the dotted arrow is referred to).

Referring to Fig. 29, in the second variation, in step S30 (Fig. 8), the groove line TL is formed. At this time, the blade edge 51 is pressed with a greater force at the position N2 than the position N1 of the upper surface SF1 of the glass substrate 4. Specifically, the position N4 is set as the position between the positions N1 and N2, and the load of the blade edge 51 is increased when the groove line TL forms the arrival position N4. In other words, the load of the groove line TL is increased between the positions N4 and N3 which are the end portions of the groove line TL as compared with the position N1. Thereby, the load other than the terminal portion is alleviated, and the crack line CL can be more easily formed from the position N2.

(Embodiment 5)

Referring to Fig. 30(A), in the breaking method of the brittle substrate according to the present embodiment, in step S30 (Fig. 8), the groove line TL from the position N1 to the side ED2 via the position N2 is formed. Next, the crack-free state (Fig. 7(A)) described in the first embodiment is maintained for a desired period of time. In the same period, as the step S40 (Fig. 8), the film 21 (Figs. 3(A) and (B)) is formed in the same manner as in the first embodiment, or the film 22 is formed in the same manner as in the second embodiment (Fig. 11(A) and (B)). In the latter case, in the above-described period, as described in the second embodiment or its modification, the slit is cut into the film 22 along the groove line TL (see the arrow in FIG. 12(A)) (for example, refer to FIG. 13 ( Incision HL) in B).

Referring to Fig. 30(B), a strain stress which releases the internal stress near the groove line TL is applied between the position N2 and the side ED2. Thereby, the crack line is caused to form along the groove line TL (FIG. 8: step S50).

Specifically, as the application of the stress, the pressed blade edge 51 is slid on the upper surface SF1 between the position N2 and the side ED2 (the area between the broken line and the side ED2 in the drawing). This sliding proceeds until the edge ED2 is reached. The blade edge 51 preferably slides in such a manner as to intersect the track of the groove line TL originally formed, and more preferably slides in a manner overlapping the track of the groove line TL initially formed. The length of the re-sliding is, for example, about 0.5 mm. Moreover, the re-sliding system may be performed on each of the trench lines TL after forming a plurality of trench lines TL (FIG. 30(A)), or one trench line may be sequentially performed for each of the trench lines TL. The process of forming and re-sliding TL.

As a variant, in order to apply a stress between the position N2 and the side ED2, it is also possible to replace The blade tip 51 is again slid, and the laser beam is irradiated between the position N2 on the upper surface SF1 and the side ED2. By the thermal stress thus generated, the strain of the internal stress near the groove line TL can also be released, thereby causing the formation of the crack line to start.

The configuration other than the above is substantially the same as the configuration of the above-described third embodiment.

(Embodiment 6)

Referring to Fig. 31(A), in the breaking method of the brittle substrate according to the present embodiment, in step S30 (Fig. 8), the blade edge 51 is displaced from the position N1 to the position N2 and then to the position N3. A groove line TL spaced apart from the edge of the upper surface SF1. The method of forming the trench line TL itself is substantially the same as that of FIG. 21(A) (Embodiment 3).

Next, the crack-free state (Fig. 7(A)) described in the first embodiment is maintained for a desired period of time. In the same period, as the step S40 (Fig. 8), the film 21 (Figs. 3(A) and (B)) is formed in the same manner as in the first embodiment, or the film 22 is formed in the same manner as in the second embodiment (Fig. 11(A) and (B)). In the latter case, in the above-described period, as described in the second embodiment or its modification, the slit is cut into the film 22 along the groove line TL (see the arrow in FIG. 12(A)) (for example, refer to FIG. 13 ( Incision HL) in B).

Referring to Fig. 31 (B), the same stress application as that of Fig. 30 (B) (Embodiment 5 or a modification thereof) is performed. Thereby, the formation of the crack line along the groove line TL is caused (FIG. 8: step S50).

Referring to Fig. 32, as a variation of the step of Fig. 31(A), in the formation of the groove line TL, the blade edge 51 may be displaced from the position N3 to the position N2 and then from the position N2 to the position N1.

The configuration other than the above is substantially the same as the configuration of the above-described third embodiment.

(Embodiment 7)

Referring to Figs. 33(A) and (B), in the above embodiments, the blade edge 51v may be used instead of the blade edge 51 (Figs. 20(A) and (B)). The blade tip 51v has a conical shape including a vertex and a conical surface SC. The protrusion PPv of the blade edge 51v is constituted by a vertex. The side portion PSv of the blade tip is formed along a virtual line extending from the apex to the conical surface SC (dashed line in Fig. 33(B)). Thereby, the side portion PSv has a convex shape that extends linearly.

In each of the above embodiments, the first and second sides of the edge of the glass substrate are short sides of a rectangle, but the first and second sides may be long sides of a rectangle. Further, the shape of the edge is not limited to a rectangle, and may be, for example, a square. Further, the first and second sides are not limited to a straight line, and may be curved. Further, in each of the above embodiments, the surface of the glass substrate is a flat surface, but the surface of the glass substrate may be curved.

A glass substrate is used as the brittle substrate which is particularly suitable for the above-described breaking method, but the brittle substrate is not limited to the glass substrate. The brittle substrate can also be made of glass other than ceramics, germanium, compound semiconductors, sapphire, or quartz.

The present invention is within the scope of the invention, and the respective embodiments can be freely combined, and the respective embodiments can be appropriately changed and omitted.

4‧‧‧Glass substrate (brittle substrate)

11‧‧‧ components

21‧‧‧ film

CL‧‧‧ crack line

DT‧‧‧ thickness direction

FB‧‧‧ external force

SF1‧‧‧ upper surface (surface)

SF2‧‧‧ lower surface

TL‧‧‧ trench line

XEt‧‧‧ end

XEs‧‧ End

VB-VB‧‧‧ line

Claims (10)

A method for breaking a brittle substrate, comprising: preparing a brittle substrate having a surface and having a thickness direction perpendicular to the surface; pressing a blade edge on the surface of the brittle substrate; and pressing the pressing step The blade edge slides on the surface of the brittle substrate, thereby plastically deforming on the surface of the brittle substrate to form a groove line having a groove shape; and the step of forming the groove line is performed as follows: Directly below the groove line, the brittle substrate is continuously connected in a direction intersecting the groove line, that is, in a state of no crack; and further, after the step of forming the groove line, on the surface of the brittle substrate Forming a film at least partially covering the trench line; after the step of forming the film, forming a crack line by stretching the crack of the brittle substrate along the groove line in the thickness direction; a line, directly below the groove line, the continuous connection of the brittle substrate in a direction crossing the groove line ; Above and breaking the brittle substrate cracks along the line. The breaking method of the brittle substrate according to claim 1, wherein the step of dividing the brittle substrate includes a step of separating the film together with the brittle substrate. A method of breaking a brittle substrate according to claim 2, wherein the film is made of an inorganic material. A method of breaking a brittle substrate according to claim 2, wherein the film is made of metal. The method for breaking a brittle substrate according to claim 1, further comprising the step of cutting the slit into the film along the groove line before the step of forming the crack line. The method for breaking a brittle substrate according to claim 5, wherein the step of cutting into the slit is This is carried out by completely cutting the film in the thickness direction of the film. The breaking method of the brittle substrate according to claim 5, wherein the step of cutting the slit is performed by partially cutting the film in the thickness direction of the film. The method of breaking a brittle substrate according to any one of claims 5 to 7, wherein the film is made of a synthetic resin. The method of breaking a brittle substrate according to any one of claims 1 to 7, wherein the brittle substrate is made of glass. The method for dividing a brittle substrate according to any one of claims 1 to 7, wherein in the step of preparing the brittle substrate, the surface is surrounded by edges including the first and second sides facing each other; In the step of sharpening, the blade edge includes a protrusion and a side portion extending from the protrusion and having a convex shape, and the step of pressing the blade edge is to apply the side of the blade edge to the surface of the brittle substrate Arranging between the protrusion and the second side; and forming the groove line, forming a first position and a second position closer to the second side than the first position The groove line; the step of forming the crack line is performed by stretching the crack of the brittle substrate along the groove line from the second position to the first position in the thickness direction.