TWI653201B - Fragmentation method of brittle substrate - Google Patents

Abstract

The present invention utilizes simple steps to break along a grooved line without cracks.

A notch is formed at the starting point N1 on the edge EG by causing the tip to straddle the edge EG of the brittle substrate 11. The first groove line TL is formed from the start point N1 to the end point N3 by moving the tool tip across the starting point N1. The first groove line TL is formed in such a manner as to obtain a crack-free state. By applying stress to the brittle substrate 11, the crack starting from the notch is extended from the starting point N1 to the end point N3, whereby the brittle substrate 11 is separated along the first groove line TL.

Description

Fragmentation method of brittle substrate

The present invention relates to a method of breaking a brittle substrate.

In the manufacture of electrical equipment such as flat panel display panels or solar panel panels, it is often necessary to break a brittle substrate such as a glass substrate. First, a scribe line is formed on the substrate, and secondly, the substrate is separated along the scribe line. The scribing can be formed by mechanically processing the substrate using a blade tip. A groove caused by plastic deformation is formed on the substrate by sliding or rolling on the substrate, and a vertical crack is formed directly under the groove. Thereafter, a stress imparting called a breaking step is performed. Thereby, the substrate is separated by causing the above-mentioned vertical crack to travel completely in the thickness direction.

The step of breaking the substrate is relatively more performed immediately after the step of forming the scribe line on the substrate. However, the step of processing the substrate between the step of forming the scribe line and the step of breaking is also proposed.

For example, according to the technique of International Publication No. 2002/104078, in the manufacturing method of an organic EL (electroluminescence) display, on the glass substrate, each region of each organic EL display is mounted before the sealing cap is mounted. Form a line. Therefore, contact between the sealing cap and the glass cutter which is a problem when the scribing is formed on the glass substrate after the sealing cap is provided can be avoided.

Further, for example, according to the technique of the international publication No. 2003/006391, in the method of manufacturing a liquid crystal display panel, two glass substrates are bonded together after forming a scribe line. Thereby, two brittle substrates can be simultaneously separated in one breaking step.

[Prior Art Literature] [Patent Literature]

[Patent Document 1] International Publication No. 2002/104078

[Patent Document 2] International Publication No. 2003/006391

According to the above-described conventional technique, the processing of the brittle substrate is performed after the scribing is formed, and the breaking step is performed by the subsequent stress application. This means that there are already vertical cracks along the entire scribe line when processing the brittle substrate. As a result, the vertical crack is unexpectedly generated in the thickness direction during processing, whereby the brittle substrate which is integrated in the process may be separated. Further, even in the case where the substrate processing step is not performed between the step of forming the scribe line and the step of dividing the substrate, it is usually necessary to transport or store the substrate after the step of forming the scribe line and before the step of dividing the substrate. The substrate is sometimes accidentally broken.

In order to solve the above problems, the inventors have developed a separate breaking technique. According to this technique, a groove line having no crack immediately below is formed as a line defining a position at which the brittle substrate is broken. The position at which the brittle substrate is broken is defined by the formation of the grooved line. Thereafter, as long as the state in which the groove line is not present in the crack is maintained, the break along the groove line is less likely to occur. By using this state, the position at which the brittle substrate is broken can be defined in advance, and the brittle substrate can be prevented from being accidentally broken before the time point at which the breakage should be made.

As described above, the groove lines are more difficult to produce the break along them than the usual scribe lines. This situation means that it is useful in preventing accidental breaks, but on the other hand means that special treatments suitable for it must be carried out for intentional breaking. In order to simplify the breaking method of the brittle substrate, it is preferable that the treatment is relatively easy.

The present invention has been made to solve the above problems, and an object thereof is to provide a brittle substrate which can be separated by a simple step without a crack line directly under the groove line. The method of breaking.

The breaking method of the brittle substrate has the following steps. A brittle substrate provided with a surface having an edge is prepared. Next, the blade edge is moved against the brittle substrate while the blade edge is pressed against the brittle substrate. The step of moving the blade tip includes the step of forming a notch at one of the edges on the edge by traversing the edge of the brittle substrate, and the step of traversing the starting point by using a step of forming the notch The step of pressing the blade toward the surface of the brittle substrate and moving the blade tip on the surface to cause plastic deformation on the surface of the brittle substrate, thereby forming the first groove line from the starting point to the other end of the surface, that is, the end point . The step of forming the first groove line is performed such that the brittle substrate directly under the first groove line is continuously connected in a direction intersecting the first groove line, that is, in a state of no crack. Next, by applying stress to the brittle substrate, the crack starting from the notch extends from the starting point to the end point, thereby breaking the brittle substrate along the first groove line.

According to the present invention, a notch formed at the edge of the brittle substrate is used as a trigger for extending the crack along the first groove line. The notch is formed only by the edge of the blade that moves when the first groove line is formed to straddle the edge of the brittle substrate. Thereby, the breaking of the brittle substrate can be performed along the first groove line by a simple procedure.

11‧‧‧Glass substrate (brittle substrate)

50, 50R, 50v‧‧‧ marking equipment

51, 51v‧‧‧ tip

51R‧‧‧marking wheel

52‧‧‧ handle

52R‧‧‧ Keeper

53‧‧ ‧ sales

61‧‧‧breaking rolls

62‧‧‧Auxiliary roller

70‧‧‧ conveyor

80‧‧‧stage

81‧‧‧Cushion

85‧‧‧ broken rod

AX‧‧‧ axis direction

CL‧‧‧crack line

CP‧‧‧ gap

CT1, CT2, XX, XIX, M1, M2, M3, PR, RT, X‧‧‧ arrows

CV, DA, DC, DL, DM‧‧ direction

DB‧‧‧direction of travel

DT‧‧‧ thickness direction

EG‧‧‧ edge

F‧‧‧load

Fp‧‧‧ vertical component

Fi‧‧‧Inside ingredients

HR‧‧‧High load range

Lines III, IVA, XVIIIA, XVIIIB, XVIIIC, XVIIID‧‧

LR‧‧‧Low load range

MS‧‧‧ surface shape

Starting point for N1‧‧

N2‧‧‧ halfway point

N3‧‧‧ end point

PF‧‧‧Outer Week

PP, PPv‧‧‧ protrusion

PS, PSv‧‧‧ side

RX‧‧‧Rotary axis

SD1‧‧‧ top surface

SD2, SD3‧‧‧ side

SC‧‧‧Conical surface

SF1‧‧‧ upper surface (surface)

SF2‧‧‧ lower surface

SF2C‧‧‧ opposite part

T1, T2, T3, T4, T5, T6‧‧ points

TL‧‧‧ Groove line (1st groove line)

TM‧‧‧ Groove line (2nd groove line)

S10, S20, S20C, S20T, S30‧‧ steps

Fig. 1 is a flow chart schematically showing a method of dividing a brittle substrate according to the first embodiment of the present invention.

Fig. 2 is a plan view schematically showing one step of the breaking method of the brittle substrate according to the first embodiment of the present invention.

3(A) to 3(C) are schematic cross-sectional views showing the steps of the breaking method of the brittle substrate according to the first embodiment of the present invention, in the field of view of the line III-III of Fig. 2, in order.

Figure 4 is a schematic cross-sectional view taken along line IVA-IVA of Figure 2, and (A) shows a state without cracks. The diagram of the structure of the groove line below, and (B) is a cross-sectional view showing a state in which a crack line is formed directly under the groove line in the same field of view.

Fig. 5 is a plan view schematically showing one step of the breaking method of the brittle substrate according to the first embodiment of the present invention.

Fig. 6 is a side view schematically showing the configuration of a scribing device used in the breaking method of the brittle substrate according to the first embodiment of the present invention.

Fig. 7(A) is a front view schematically showing the configuration of the scribing wheel and the pin of Fig. 6, and Fig. 7(B) is a partially enlarged view of Fig. 7(A).

Fig. 8 is a cross-sectional view schematically showing a step of a method of dividing a brittle substrate according to the first embodiment of the present invention.

Fig. 9 is a cross-sectional view schematically showing a step of a method of dividing a brittle substrate according to the first embodiment of the present invention.

Fig. 10 is a schematic side view of the field of view corresponding to the arrow X of Fig. 9.

Fig. 11 is a cross-sectional view schematically showing a step of a method of dividing a brittle substrate according to the first embodiment of the present invention.

Fig. 12 is a cross-sectional view schematically showing a step of a method of dividing a brittle substrate according to the first embodiment of the present invention.

Fig. 13 is a plan view schematically showing one step of the breaking method of the brittle substrate according to the second embodiment of the present invention.

Fig. 14 is a plan view schematically showing one step of the breaking method of the brittle substrate according to the third embodiment of the present invention.

Fig. 15 is a plan view schematically showing one step of the breaking method of the brittle substrate according to the third embodiment of the present invention.

Fig. 16 is a plan view schematically showing one step of the breaking method of the brittle substrate according to the third embodiment of the present invention.

17(A) to (D) are diagrams schematically showing a brittle substrate according to Embodiment 4 of the present invention. Partial view of one of the steps of the breaking method.

Figure 18(A) is a schematic partial cross-sectional view taken along line XVIIIA-XVIIIA of Figure 17(A), (B) is a schematic partial cross-sectional view taken along line XVIIIB-XVIIIB of Figure 17(B), and (C) is taken along Figure 17 ( A schematic partial cross-sectional view of the line XVIIIC-XVIIIC of C), and (D) is a schematic partial cross-sectional view taken along line XVIIID-XVIIID of Fig. 17(D).

Fig. 19(A) is a side view schematically showing the configuration of a scribing device used in the breaking method of the brittle substrate according to the fifth embodiment of the present invention, and (B) is an arrow XIX of Fig. 19(A). The bottom view of the blade tip in the corresponding field of view.

Fig. 20 (A) is a side view schematically showing the configuration of a scribing device used in the breaking method of the brittle substrate according to the modification of the fifth embodiment of the present invention, and (B) and Fig. 20 (A) The bottom view of the tool tip in the field of view corresponding to arrow XX.

Hereinafter, a method of dividing a brittle substrate according to each embodiment of the present invention will be described based on the drawings. In the following drawings, the same or corresponding parts are denoted by the same reference numerals, and the description thereof is not repeated.

(Embodiment 1)

Fig. 1 is a flow chart schematically showing a method of dividing the glass substrate 11 (brittle substrate) of the present embodiment. Fig. 2 is a plan view schematically showing a state immediately after completion of step S20 (Fig. 1). 3(A) to (C) are schematic partial cross-sectional views showing the steps sequentially along the line III-III of Fig. 2.

First, the glass substrate 11 is prepared (FIG. 1: Step S10). The glass substrate 11 includes a surface SF1 (surface) having an edge EG and a lower surface SF2. Further, the glass substrate 11 has a thickness direction DT perpendicular to the upper surface SF1. Further, a scribing tool having a scribing wheel 51R provided with a blade edge is prepared. The details of the scribing apparatus will be described below.

Next, the blade edge of the scribing wheel 51R is brought into contact with the edge EG of the upper surface SF1 of the glass substrate 11 by the movement of the scribing wheel 51R shown by the arrow M1 (Fig. 3(A)). Second, one The blade edge is pressed against the glass substrate 11 to move the blade edge on the glass substrate 11 (FIG. 1: Step S20). Hereinafter, this step will be described.

First, the blade edge straddles the edge EG of the glass substrate 11 by the movement of the scribing wheel 51R shown by the arrow M2 (Fig. 3(B)). Thereby, the notch CP (FIG. 3(C)) is formed at a position on the edge EG, that is, the starting point N1 (FIG. 2) (FIG. 1: Step S20C).

Then, the blade tip of the starting point N1 is pushed over the upper surface SF1 of the glass substrate 11 by the step of forming the notch CP as described above, and is set as indicated by an arrow M3 (Fig. 3(C)). The knurled wheel 51R having the tip end moves on the upper surface SF1. Thereby, plastic deformation occurs on the upper surface SF1 of the glass substrate 11. As a result, the groove line TL (first groove line) is formed from the starting point N1 to the other end position on the upper surface SF1, that is, the end point N3 (FIG. 1: Step S20T).

Referring to FIG. 4(A), the step of forming the trench line TL is such that a state in which the glass substrate 11 is continuously connected in a direction DC intersecting the trench line TL directly under the trench line TL, that is, a crack-free state is obtained. get on. In the crack-free state, although the groove line TL is formed by plastic deformation, cracks along the groove line TL are not formed. Thereby, even if a bending moment is applied to the glass substrate 11, the division along the groove line TL is less likely to occur. In order to obtain a crack-free state, the load of the blade tip 11 being pressed against the glass substrate 11 may be excessively large. 4(B) shows a comparative example of FIG. 4(A), and shows a state in which the groove line TL and the crack line CL which is a crack extending directly below the groove line TL are formed.

The desired number of trench lines can be obtained by repeating the above-described formation steps of the trench lines TL as needed. FIG. 2 illustrates a case where three groove lines TL are formed.

Referring to Figure 5, the breaking step is performed next. Specifically, by applying stress to the glass substrate 11, the crack starting from the notch CP is extended from the starting point N1 to the end point N3, whereby the glass substrate 11 is separated along the groove line TL (FIG. 1: Step S30). The breaking step can be performed plural times depending on the number of groove lines TL. Furthermore, a more detailed method of the breaking step will be described later.

The glass substrate 11 is separated along the groove line TL by the above steps.

Referring to Fig. 6 and Fig. 7, the details of the scribing device 50R having the scribing wheel 51R will be described below.

The scribing tool 50R is scribed to the glass substrate 11 by being attached to a scribing head (not shown) so as to be relatively moved with respect to the glass substrate 11. The scribing tool 50R has a scribing wheel 51R, a retainer 52R, and a pin 53. The scribing wheel 51R has a substantially disk-like shape, and its diameter is typically about several mm. The scribing wheel 51R is rotatably held around the rotation axis RX via the pin 53 and held by the holder 52R.

The scribing wheel 51R has a peripheral portion PF provided with a blade edge. The outer peripheral portion PF extends in an annular shape around the rotation axis RX. As shown in Fig. 7(A), the outer peripheral portion PF is ridged at a visual level to form a blade edge including a ridge line and an inclined surface. On the other hand, at the microscope level, the ridge line of the outer peripheral portion PF is finely formed by the portion of the scribing wheel 51R that actually intrudes into the glass substrate 11 (below the two-point chain line of FIG. 7(B)). Surface shape MS. The surface shape MS is in a front view (Fig. 7(B)), preferably in the shape of a curve having a finite radius of curvature.

The scribing wheel 51R is formed using a hard material such as cemented carbide, sintered diamond, polycrystalline diamond, or single crystal diamond. From the viewpoint of reducing the surface roughness of the ridge line and the inclined surface, the entire scribing wheel 51R may be made of single crystal diamond.

Next, a method of using the scribing device 50R will be described. The scribe line forming the groove line TL (Fig. 3(C)) is formed by moving the blade edge of the scribing tool 50R on the surface SF1 of the glass substrate 11 (see Fig. 6). At this time, the load F applied to the blade edge has a vertical component Fp parallel to the thickness direction DT of the glass substrate 11 and an in-plane component Fi parallel to the upper surface SF1. The traveling direction DB of the scribing wheel 51R caused by the rolling (arrow RT) of the scribing wheel 51R is the same as the direction of the in-plane component Fi. In other words, the direction in which the groove line TL is formed is the same as the direction in which the in-plane component Fi is formed.

Next, the breaking step which is particularly suitable for the present embodiment will be described below.

Referring to Fig. 8, the substrate 80 is interposed between the upper surface SF1 of the glass substrate 11 via the spacer 81. In the opposite manner, the glass substrate 11 (FIG. 2) on which the groove lines TL are formed is placed on the stage 80 via the spacer 81. The backing 81 includes a material that is more deformable than the material of the glass substrate 11 and the stage 80.

Referring to Fig. 9 and Fig. 10, the breaking lever 85 is prepared. The breaking lever 85 preferably has a shape that protrudes in such a manner as to locally press the surface of the glass substrate 11, as shown in Fig. 10. The shape is roughly V-shaped. As shown in Fig. 9, the protruding portion extends linearly.

Next, the breaking rod 85 is brought into contact with a portion of the lower surface SF2 of the glass substrate 11. The contact portion is separated from the opposite portion SF2C opposite to the notch CP in the thickness direction (the longitudinal direction of FIG. 9) from the lower surface SF2.

Next, as indicated by the arrow CT1, the above-mentioned contact portion spreads along the groove line TL and approaches toward the side of the opposing portion SF2C. At the initial contact, or by extension of the subsequent contact portion, the breaking bar 85 is in contact with the portion of the lower surface SF2 opposite to the groove line TL and facing away from the notch CP. The state of leaving.

Referring to Fig. 11, the contact portion reaches the opposite portion SF2C as indicated by an arrow CT2. In other words, the breaking lever 85 first applies stress to the groove line TL by the above-described steps, and thereafter applies stress to the notch CP at the same time. The crack is caused to extend from the notch CP along the groove line TL by the stress (refer to the arrow PR of FIG. 12).

The division of the glass substrate 11 is performed by the above-described breaking step (Fig. 5).

According to the present embodiment, the notch CP formed on the edge EG of the glass substrate 11 is used as a trigger for extending the crack along the groove line TL. This notch CP is formed only by the edge EG of the glass substrate 11 which is moved by the cutting edge when the groove line TL is formed. Thereby, the division of the glass substrate 11 can be performed along the groove line TL by a simple procedure.

Further, in the formation of the notch CP, the cutting edge of the scribing wheel 51R, that is, the rotating blade edge is used. Thereby, it is possible to suppress the damage of the blade tip when the blade edge straddles the edge EG of the glass substrate 11 as compared with the case of using a blade tip fixed like a diamond pen.

(Embodiment 2)

Referring to Fig. 13, in the present embodiment, a step of forming a high load section HR as one of the trench lines TL and a step of forming the low load section LR as one of the trench lines TL are performed. The high load section HR is formed from the starting point N1 to the intermediate point N2 between the starting point N1 and the ending point N3. The low load section LR is formed from the midway point N2 to the end point N3. The load applied to the tool tip in the step of forming the low load interval LR is lower than the load used in the step of forming the high load interval HR.

In addition, the configuration other than the above is substantially the same as the configuration of the first embodiment, and the same or corresponding elements are denoted by the same reference numerals, and the description thereof will not be repeated.

According to the present embodiment, the high-load section HR which is a portion extending from the notch CP in the groove line TL is formed by plastic deformation due to high load. Thereby, it is easy to generate a crack from the notch CP to the groove line TL as compared with the case where the entire groove line TL is formed by plastic deformation due to the low load used in the low load section LR. As a result, in the breaking step (Figs. 8 to 12), cracks caused by the notch CP can be more reliably generated. Thereby, it is possible to more reliably perform the extension of the crack to separate the glass substrate 11 along the groove line TL.

Further, in FIG. 2, the end point N3 is separated from the edge EG of the glass substrate 11, but the end point N3 may also be located on the edge EG of the glass substrate 11 (in the example of FIG. 2, on the edge of the right side of the surface SF1 of the glass substrate 11) .

(Embodiment 3)

Referring to Fig. 14, first, in the same manner as in the first embodiment, the groove line TL having the notch CP at the starting point and extending to the end point is formed in the direction DL.

Referring to Fig. 15, the blade tip is pressed against the upper surface SF1 of the glass substrate 11 by applying a load, and the blade edge is moved toward the upper surface SF1 in the direction DM. Thereby, plastic deformation occurs on the upper surface SF1 of the glass substrate 11, and a groove line TM (second groove line) is formed between the points T1 and T6. The formation of the groove line TM and the groove in the first embodiment The method described in the line TL (Fig. 4(A)) is the same, and the groove line TM is obtained in a manner of obtaining a crack-free state.

A high load section HR is formed between the point T1 and the point T2, between the points T3 and T4, and between the points T5 and T6 as one of the groove lines TM. A low load section LR is formed between the points T2 and T3 and between the points T4 and T5 as a part of the groove line TM. The load applied to the tool tip in the step of forming the high load interval HR is higher than the load used in the step of forming the low load interval LR. The high load interval HR intersects the groove line TL. Further, the method of forming the trench line TM can be performed in the same manner as the method of forming the trench line TL.

Next, by the same breaking step as in the first embodiment, the crack is extended along the groove line TL with the notch CP as a starting point. Thereby, the glass substrate 11 is separated along the groove line TL (Fig. 16). Taking this break as an opportunity, the crack extends only in the high load interval HR in the groove line TM. As a result, a crack line CL is formed along one portion of the groove line TM. Specifically, a crack line CL is formed in the high load section HR on a portion between the side newly formed by the division and one of the midway points passing through the side.

Further, it is difficult to form the crack line CL even in the high load section HR in the portion between the side newly formed by the division and the other of the midway points. The reason for this is that the ease of stretching of the crack along the crack line CL has a directional dependence. It is presumed that this direction dependence is caused by the distribution of internal stress generated when the glass substrate 11 is scribed.

In the high load section HR, as shown in FIG. 4(B), the glass substrate 11 is continuous under the groove line TM, and is continuous in the direction of the intersection with the direction in which the groove line TM extends due to the crack line CL. The connection is disconnected. Here, "continuous connection", in other words, is not connected by cracks. Further, in a state where the continuity is disconnected as described above, portions of the glass substrate 11 can also be in contact with each other via the crack of the crack line CL.

Then, stress is applied to the glass substrate 11 by the same breaking step as in the first embodiment, whereby the crack propagates along the crack line CL as a starting point along the low load section LR. Thereby, the glass substrate 11 is separated along the groove line TM. That is, in addition to the division along the above-mentioned groove line TL, The line is broken along the groove line TM.

According to this embodiment, substantially the same effects as those of the first embodiment can be obtained. Further, the position of the glass substrate 11 to be separated can be defined by the groove line TL and the groove line TM intersecting therewith.

(Embodiment 4)

Referring to Fig. 17 (A) and Fig. 18 (A), first, a breaking device of the glass substrate 11 of the present embodiment will be described.

The breaking device has a scribing device 50R, a conveyor 70, a breaking roller 61, and an auxiliary roller 62. The conveyor 70 conveys the glass substrate 11 in the direction CV while exposing the upper surface SF1 of the glass substrate 11. The scribing tool 50R is fixed to a scribing head (not shown), and is in contact with the glass substrate 11 moved by the conveyor 70 to scribe the upper surface SF1 of the glass substrate 11.

The breaking roller 61 is a member for performing a breaking step to locally press the lower surface SF2 of the glass substrate 11. The auxiliary roller 62 is in contact with the roller of the glass substrate 11 on the opposite surface, that is, the upper surface SF1, by being pressed against the lower surface SF2 by the breaking roller 61. The auxiliary roller 62 is disposed at a position different from the breaking roller 61 in a planar layout (FIG. 17(A)) so that the glass substrate 11 can be stably deflected by the pressing of the breaking roller 61. It is disposed so as to be separated from the breaking roller in the direction of the rotation axis (the longitudinal direction of FIG. 17(A)).

Further, in FIGS. 17(A) and 18(A), the conveyor 70 is schematically shown by a two-dot chain line for easy observation. The same is true in other figures.

Next, the following description will be made on the breaking method using the above-described breaking device.

The glass substrate 11 is conveyed in the conveyance direction CV as the conveyer 70 moves to the conveyance direction CV. Thereby, the blade edge of the scribing wheel 51R which the scribing tool 50R has has straddles the upper surface SF1 from the edge EG of the glass substrate 11. A notch CP is formed on the edge EG of the glass substrate 11 by the straddle.

The blade tip on the upper surface SF1 is moved by the glass substrate 11 in the transport direction CV, On the other hand, the upper surface SF1 of the glass substrate 11 is relatively moved in the opposite direction to the transport direction CV. The moving direction of the relative orientation of the blade edge with respect to the upper surface SF1 is the direction corresponding to the direction DB (Fig. 17(A)). In this movement, a high load section HR of the groove line TL having the position of the notch CP as a starting point is formed on the upper surface SF1 by applying a load to the blade edge.

Referring to FIGS. 17(B) and 18(B), after the glass substrate 11 is further conveyed, the load applied to the blade edge is made smaller than the load in the high load section HR, thereby starting the low load section LR in which the groove line TL is formed. .

Referring to FIGS. 17(C) and 18(C), the glass substrate 11 is further conveyed, and stress application by the breaking roller 61 and the auxiliary roller 62 to the high load section HR in which the notch CP is provided is performed. Thereby, the crack spreads from the notch CP, and as a result, the crack line CL is formed in the high load section HR. In FIG. 18(C), the crack line CL penetrates the glass substrate 11 in the thickness direction and reaches the lower surface SF2.

Referring to FIGS. 17(D) and 18(D), the glass substrate 11 is further conveyed, and the stress application to the low load section LR by the breaking roller 61 and the auxiliary roller 62 is started. The crack extends from the above-mentioned crack line CL until the portion of the low load section LR subjected to stress application. Hereinafter, as the glass substrate 11 is conveyed, the cracks are stretched in the low load section LR.

When the crack is stretched, the low load section LR is extended by the use of the scribing tool 50R to form the low load section LR. Thereby, the end of the groove line TL is separated from the starting point, and the glass substrate 11 is separated according to the length of the groove line TL. That is, the continuity of the glass substrate 11 is divided.

According to the present embodiment, the glass substrate 11 can be continuously separated by using the crack which is stretched by the notch CP. Thereby, the glass substrate 11 can be separated without being restricted by the length of the glass substrate 11.

Further, unlike the high load section HR, in the low load section LR, it is difficult for the crack to extend to a portion that has not been subjected to the stress applied by the breaking roller 61. Thus, in Figure 18(D) In the continuous breaking step shown, it is possible to prevent the crack from reaching the tip or extending beyond the position of the tip. Thereby, the continuity of the glass substrate 11 can be stably performed.

(Embodiment 5)

Referring to Figs. 19(A) and (B), when the damage of the blade edge over the edge EG of the glass substrate 11 does not become a particular problem, a scribing device 50 having a fixed tip can also be used (Fig. 19). (A) and (B)).

The scribing tool 50 scribes the glass substrate 11 by relatively moving relative to the glass substrate 11 by being attached to a scribing head (not shown). The scribing tool 50 has a blade tip 51 and a handle 52. The tip 51 is held by the shank 52.

The blade tip 51 is provided with a top surface SD1 (first surface) and a plurality of surfaces surrounding the top surface SD1. These multiple 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 face different directions from each other and are adjacent to each other. The blade edge 51 has a vertex where the top surface SD1, the side surfaces SD2, and SD3 merge, and the apex constitutes the protrusion PP of the blade edge 51. Further, the side faces SD2 and SD3 form a ridge line constituting the side portion 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 in a line shape.

The tip 51 is preferably a diamond pen. That is, it is preferable that the blade edge 51 is made of diamond. In this case, the hardness can be easily made high and the surface roughness can be made small. More preferably, the tip 51 is made of single crystal diamond. Further, in crystallography, it is preferable that the top surface SD1 is a {001} plane, and each of the side surfaces SD2 and SD3 is a {111} plane. In this case, although the side faces SD2 and SD3 have mutually different directions, they are crystallographically equivalent crystal faces.

Further, a diamond which is not a single crystal may be used, and for example, a polycrystalline diamond synthesized by a CVD (Chemical Vapor Deposition) method may also be used. Alternatively, a polycrystalline diamond obtained by sintering particulate graphite or non-graphite carbon in a case where a bonding material such as an iron group element is not contained, or a sintered diamond in which diamond particles are bonded by a bonding material such as an iron group element may be used. .

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

In the formation of the groove line TL using the scribing tool 50, the pressed blade edge 51 is slid in the direction DB on the upper surface SF1. The direction DB is a direction opposite to a direction in which the direction in which the protrusion portion PP extends along the side portion PS is projected onto the upper surface SF1, and substantially corresponds to a direction opposite to a direction in which the axial direction AX is projected onto the upper surface SF1.

Further, when the groove line TM (FIG. 15) is formed without forming the notch CP at the edge EG of the glass substrate 11, the blade edge 51 can also slide in the direction DA opposite to the direction DB. In this case, the moving direction of the blade edge on the upper surface SF1 of the glass substrate 11 is reversed (in the direction opposite to the direction DM in Fig. 15).

The scribing tool 50R and the scribing tool 50 can also be used separately according to the groove line. In particular, in the third embodiment, the groove line TL can be formed by the scribing tool 50R, and the groove line 50 can be formed by the scribing tool 50 on the side without the blade edge.

Referring to Figs. 20(A) and (B), a scribing device 50v may be used as a modification of the embodiment. The blade edge 51v of the scribing tool 50v has a conical shape having 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 edge is constituted by an imaginary line (dashed line in Fig. 20(B)) extending from the vertex along the conical surface SC. Thereby, the side portion PSv has a convex shape extending in a line shape.

The breaking method of the brittle substrate of each of the above embodiments can be particularly preferably applied to a glass substrate, but the brittle substrate can also be made of a material other than glass. For example, as a material other than glass, ceramics, ruthenium, compound semiconductors, sapphire or quartz can also be used.

Claims (6)

A method for breaking a brittle substrate, comprising: preparing a brittle substrate provided with a surface having an edge; and step of moving the blade edge on the brittle substrate while pressing the blade edge toward the brittle substrate; The step of moving the cutting edge includes: forming a notch at a position on the edge, that is, a starting point, by traversing the edge of the brittle substrate; and using a step of forming the notch by one side The blade tip is pushed over the surface of the brittle substrate and the blade edge is moved on the surface to cause plastic deformation on the surface of the brittle substrate, thereby from the starting point to the surface a step of forming a first trench line at another position, wherein the step of forming the first trench line is to obtain the fragile substrate directly under the first trench line and the first trench line a state in which the direction of the intersection is continuously connected, that is, a state in which no crack is present; and the method of breaking the brittle substrate further includes the following steps: Stress is applied to the brittle substrate, and a crack starting from the notch is extended from the starting point toward the end point, thereby breaking the brittle substrate along the first groove line. The breaking method of the brittle substrate according to claim 1, wherein the step of moving the blade edge is performed by using a scribing wheel having an outer peripheral portion around a rotating shaft, and the blade edge is provided on the outer peripheral portion. The breaking method of the brittle substrate according to claim 1, wherein the step of forming the first groove line includes: forming a high load section as the first groove line from the starting point to a middle point between the starting point and the end point a part of the steps; and a step of forming a low load section as one of the first groove lines from the midway point to the end point; and applying a load to the blade tip in the step of forming the low load section is lower than forming the high load section The load used in the steps. The breaking method of the brittle substrate according to claim 2, wherein the step of forming the first groove line includes: forming a high load section as the first groove line from the starting point to a middle point between the starting point and the end point And a step of forming a low load section as one of the first groove lines from the midway point to the end point; and applying a load to the blade tip in the step of forming the low load section is lower than The load used in the step of forming the above-described high load section. The method for breaking a brittle substrate according to any one of claims 1 to 4, further comprising the step of: pressing the blade tip onto the surface of the brittle substrate while applying a load, and causing the blade tip to be Moving on the surface, plastic deformation occurs on the surface of the brittle substrate, thereby forming a second groove line; and the step of forming the second groove line is obtained directly below the second groove line The brittle substrate is continuously connected in a direction intersecting the second groove line, that is, in a state of no crack, and the step of forming the second groove line includes forming a low load section as the second groove line And a step of forming a high load section as a part of the second groove line; and applying a load to the blade tip in the step of forming the high load section is higher than a step of forming the low load section The load used in the above, the high load section intersects with the first groove line; the breaking method of the brittle substrate further includes: breaking the fragile along the first groove line The opportunity of the step substrate cracks a step of forming a crack line along one of the second groove lines only in the high load section of the second groove line; and applying a stress to the brittle substrate to cause a crack to be the crack line The step of extending the fragile substrate along the second groove line by extending the starting point along the low load section. The method for breaking a brittle substrate according to any one of claims 1 to 4, wherein, in the step of dividing the brittle substrate along the first groove line, forming the first groove during the stretching of the crack The first groove line is extended by the step of the line.