TW201741106A - Segmentation method for brittle substrate - Google Patents

Abstract

To secure an easy preparation of a blade tip and a sufficient lifetime of the tip when the tip having an apex where three faces joint is slid with the ridgeline on the back side. A blade tip 51 is prepared which has a first face SD1, a second face SD2 adjacent to the first face SD1, and a third face SD3 that makes a ridgeline PS by adjacency to the second face SD2 and makes an apex PP by adjacency to each of the first face SD1 and the second face SD2. The ridgeline PS is processed by bevelling. A trench line TL having a groove shape is cracklessly formed on one face SF1 of the brittle substrate 4 by sliding the tip 51 on one face SF1 of the brittle substrate 4 from the ridgeline PS in a direction toward the first face SD1. A crack line CL is formed along the trench line TL. The brittle substrate 4 is segmented along the 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 using a sliding edge of a blade.

In the manufacture of electrical equipment such as flat panel displays or solar panel panels, it is often necessary to break the brittle substrate. In a typical breaking method, first, a crack line is formed on a brittle substrate. In the present specification, the term "crack line" means a crack that partially advances in the thickness direction of the brittle substrate and linearly extends on the surface of the brittle substrate. Next, a so-called breaking step is performed. Specifically, by applying stress to the brittle substrate, the crack of the crack line is completely advanced in the thickness direction. Thereby, the brittle substrate is broken along the crack line.

According to Patent Document 1, the depression on the upper surface of the glass sheet is generated at the time of cutting. In Patent Document 1, the recess is referred to as "line". Further, at the same time as the scribe line, a crack extending from the scribe line in the downward direction is generated. As disclosed in the technique of Patent Document 1, in the conventional technique of the prior art, a crack line is formed simultaneously with the formation of the scribe line.

According to Patent Document 2, there is proposed a breaking technique which is significantly different from the above-described typical breaking technique. According to this technique, first, a plastic deformation is performed by sliding of the leading edge of the blade on the brittle substrate, and a groove shape called "scribe line" in Patent Document 2 is formed. In this description In the book, the shape of the groove will be referred to as a "groove line" in the future. At the point in time when the groove line is formed, no crack is formed below it. Then, the crack line is formed by stretching the crack along the groove line. That is, unlike the typical technique, once the groove line without the crack is formed, a crack line is formed along the groove line. The usual breaking step is then carried along the crack line.

In the present specification, a technique of actively utilizing a groove line not accompanied by a crack as in the technique of Patent Document 2 described above is referred to as a "crack-free scribe technique". The groove line formed in the crack-free scribing technique can be formed by sliding the leading edge of the blade with a lower load than the typical scribing formed at the same time as the crack. If the load is small, the damage applied to the leading edge of the blade also becomes small. Therefore, according to the breaking technique, the life of the leading edge of the blade can be extended. As one of the configurations of the leading edge of the blade, according to the above Patent Document 2, a vertice having three faces intersecting and a ridge extending therefrom is disclosed. Specifically, the leading edge of the blade has an apex at which the top surface intersects the first side surface and the second side surface, and a ridge line formed by the first side surface and the second side surface. As a direction in which the leading edge of the blade slides on the brittle substrate, a first direction from the top surface toward the ridge line and a second direction from the ridge line toward the top surface are disclosed.

[Previous Technical Literature]

[Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. Hei 9-188534

[Patent Document 2] International Publication No. 2015/151755

The blade leading edge is not limited to the crack-free scribe technique, and is widely used in the sculpt technique which is accompanied by the typical cracking. In the typical scribing technique, the leading edge The first direction of the sliding direction is standard. In other words, the ridge line is the front side and the top surface is the back side. The reason for this is that it is easy to suppress damage to the leading edge of the blade. On the other hand, in the crack-free scribing technique, since the load on the leading edge of the blade is low, damage to the leading edge of the blade is suppressed, and the second direction is also sufficiently practical. Further, in the crack-free scribing technique, there is a case where the second direction is not particularly desired depending on the use thereof. Regarding the specific composition of the leading edge of the blade suitable for such a situation, the research on the technique of crack-free scoring has just begun, and no specific research has been conducted.

The leading edge of the blade used for industrial purposes is expected to be easy to prepare because of the relatively high frequency of replacement. In particular, when the second direction is selected as the sliding direction of the leading edge of the blade, it is easier to apply damage to the leading edge of the blade than when the first direction is selected. Therefore, the life of the leading edge of the blade is likely to be shortened, and the frequency of replacement of the leading edge of the blade is likely to become high. Therefore, it is further desirable that the leading edge of the blade be an easy preparer.

The present invention has been made in order to solve the above problems, and an object of the invention is to provide a method for breaking a brittle substrate, which is a case where a blade leading edge having a vertex of three faces intersects with a ridge line as a rear side and slides The leading edge of the blade can be easily prepared and the full life of the leading edge of the blade can be ensured.

The breaking method of the brittle substrate according to one aspect of the present invention has the following steps a) to e).

a) Prepare a brittle substrate having a face and a thickness direction perpendicular to one face.

b) preparing a leading edge of the blade, the leading edge of the blade having: a first surface; a second surface adjacent to the first surface; and a third surface formed by forming a ridge line adjacent to the second surface With each of the first side and the second side Adjacent to form a vertex. The ridge line is the one that has not been chamfered.

c) A groove line having a groove shape is formed on one surface of the brittle substrate by plastic deformation by sliding the leading edge of the blade toward the first surface on one surface of the brittle substrate. The groove lines are formed in a non-cracked state, that is, a state in which the brittle substrates are continuously connected in a direction intersecting the groove lines below the groove lines.

d) After step c), the crack line is formed by stretching the crack of the brittle substrate in the thickness direction along the groove line. By the crack line, the connection of the brittle substrate in the direction intersecting the groove line is interrupted below the groove line.

e) Break the brittle substrate along the crack line.

The breaking method of the brittle substrate according to another aspect of the present invention has the following steps a) to e).

a) Prepare a brittle substrate having a face and a thickness direction perpendicular to one face.

b) preparing a leading edge of the blade, the leading edge of the blade having: a first surface; a second surface adjacent to the first surface; and a third surface formed by forming a ridge line adjacent to the second surface Adjacent to each of the first surface and the second surface, an apex is formed. The leading edge of the blade has a radius of curvature of 2 μm or less in a cross section perpendicular to the ridge line.

c) A groove line having a groove shape is formed on one surface of the brittle substrate by plastic deformation by sliding the leading edge of the blade toward the first surface on one surface of the brittle substrate. The groove lines are formed in a non-cracked state, that is, a state in which the brittle substrates are continuously connected in a direction intersecting the groove lines below the groove lines.

d) After step c), the crack line is formed by stretching the crack of the brittle substrate in the thickness direction along the groove line. By the crack line, below the groove line, the brittle substrate is in the groove The continuity of the continuity of the slot line is interrupted.

e) Break the brittle substrate along the crack line.

According to the breaking method of the brittle substrate according to an aspect of the present invention, the ridgeline of the leading edge of the blade is a non-chamfered processor. Thereby, it is easier to prepare the leading edge of the blade than when the ridgeline of the leading edge of the blade is a chamfered processor. Moreover, by using the crack-free scribe technique, the load on the leading edge of the blade can be reduced. Thereby, the slanting of the ridge line can be performed, and the sufficient life of the leading edge of the blade can be ensured.

According to the breaking method of the brittle substrate according to another aspect of the present invention, the leading edge of the blade has a radius of curvature of 2 μm or less in a cross section perpendicular to the ridge line. Such a radius of curvature can be easily obtained only by controlling chamfering with respect to the ridge line after forming one surface opposite to the ridge line. Therefore, the leading edge of the blade can be easily prepared. Moreover, by using the crack-free scribe technique, the load on the leading edge of the blade can be reduced. Thereby, the slanting of the ridge line can be performed, and the sufficient life of the leading edge of the blade can be ensured.

Edge of ED‧‧

AL‧‧‧Auxiliary line

CL‧‧‧crack line

SD1‧‧‧ top surface (1st side)

SD2‧‧‧ side (2nd side)

SD3‧‧‧ side (3rd side)

SF, SF1‧‧‧ upper surface (one side)

PP‧‧‧ vertex

TL‧‧‧ trench line

PS‧‧‧ ridgeline

CLa‧‧‧Assisted Crack Line

TLa‧‧‧Auxiliary groove line

4‧‧‧Glass substrate (brittle substrate)

51‧‧‧blade front

51a‧‧‧Auxiliary edge

Fig. 1 is a side view schematically showing the configuration of a cutting instrument used in the breaking method of the brittle substrate according to the first embodiment of the present invention.

Figure 2 is a schematic plan view of the viewpoint of the arrow II of Figure 1.

Figure 3 is a partial enlarged view of the vicinity of the apex of Figure 2.

Fig. 4 is a graph schematically showing a surface distribution for calculating a radius of curvature of a section perpendicular to the ridgeline of Fig. 3.

Fig. 5 is a flow chart schematically showing the configuration of a breaking method of the brittle substrate according to the first to fifth embodiments of the present invention.

Fig. 6 is a plan view schematically showing a first step of the breaking method of the brittle substrate according to the first embodiment of the present invention.

Fig. 7 is a schematic end view taken along line VII-VII of Fig. 6.

Fig. 8 is a plan view schematically showing a second step of the breaking method of the brittle substrate according to the first embodiment of the present invention.

Figure 9 is a schematic end view taken along line IX-IX of Figure 8.

FIG. 10 is a plan view schematically showing a configuration of a cutting instrument used in the breaking method of the brittle substrate of Comparative Example 1. FIG.

Fig. 11 is a side view showing the breaking shape of the brittle substrate according to the embodiment of the first embodiment.

Fig. 12 is a side view showing the breaking shape of the brittle substrate of Comparative Example 3.

Fig. 13 is a flow chart showing the configuration of a method of forming a groove line in the breaking method of the brittle substrate according to the second embodiment of the present invention.

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

Figure 15 is a schematic end view taken along line XV-XV of Figure 14.

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

Fig. 17 is a plan view schematically showing a third step of the breaking method of the brittle substrate according to the third embodiment of the present invention.

FIG. 18 is a view schematically showing a method of dividing a brittle substrate according to Embodiment 4 of the present invention; A top view of the 1 step.

Fig. 19 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. 20 is a cross-sectional view showing the configuration of a blade leading edge used in the breaking method of the brittle substrate according to the fifth embodiment of the present invention.

Fig. 21 is a cross-sectional view showing the configuration of the leading edge of the auxiliary blade used in the breaking method of the brittle substrate according to the fifth embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described based on the drawings. In the following drawings, the same or corresponding components are designated by the same reference numerals, and the description is not repeated.

<Embodiment 1>

(Composition of cutting instruments)

First, the configuration of the cutting tool 50 used in the step of forming the groove line of the method for dividing the glass substrate 4 (brittle substrate) of the present embodiment will be described with reference to FIG. 1 and FIG. The cutting instrument 50 has a blade leading edge 51 and a shank 52. The leading edge 51 of the blade is held by being fixed to the shank 52 as its holder.

A top surface SD1 (first surface) and a plurality of surfaces surrounding the top surface SD1 are provided on the blade leading edge 51. 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 leading edge 51 has an apex where the top surface SD1, the side surfaces SD2, and SD3 intersect. The protrusion of the blade leading edge 51 is formed by the vertex PP. Further, the side faces SD2 and SD3 are formed to form the side of the blade leading edge 51. The ridgeline PS. The ridge line PS extends linearly from the apex PP and has a convex shape extending linearly. According to the above configuration, the blade leading edge 51 has a top surface SD1, a side surface SD2 adjacent to the top surface SD1, and a side surface SD3 which is formed adjacent to the side surface SD2 to form the ridge line PS and by the top surface SD1 Each of the side faces SD2 is adjacent to each other to form a vertex PP.

The ridge line PS is a person who has not been chamfered. Therefore, the ridgeline of the blade leading edge 51 has a sharp shape. Specifically, the blade leading edge 51 has a radius of curvature of 2 μm or less, preferably has a radius of curvature of 1 μm or less, and has a radius of curvature as a cross section perpendicular to the ridge line PS (hereinafter, simply referred to as "curvature radius of the ridge line PS"). . Hereinafter, an example of a method of measuring the radius of curvature will be described.

Referring to Fig. 3, the radius of curvature can be calculated from the measurement results of the surface distributions of the side faces SD2 and SD3 on the measurement line SR. The measurement line SR is located in the action portion ER which acts substantially on the glass substrate 4 in the vicinity of the vertex PP in the blade leading edge 51. The measurement line SR is orthogonal to the ridge line PS at a position away from the vertex PP. The action portion ER has a dimension L1 in a direction orthogonal to the ridge line PS and a dimension L2 in a direction along the ridge line PS. Typically, the dimension L1 is 30 μm or more and 50 μm or less, and the dimension L2 is 10 μm or more and 30 μm or less. The interval LD between the vertex PP and the measurement line SR is an interval in which the influence on the surface distribution caused by the presence of the vertex PP is sufficiently small, and is, for example, about 5 μm. Fig. 4 is a view schematically showing the surface distribution of the measurement result of the relationship between the position on the measurement line SR and the height H. The measurement of the surface distribution can be carried out, for example, using a laser microscope. The radius of curvature can be calculated by applying a circle RR to the position at which the obtained surface is distributed over the ridge line PS.

Preferably, the leading edge 51 of the blade is a diamond dot. That is, the blade leading edge 51 is preferably made of diamond in terms of reducing hardness and surface roughness. More preferably, the leading edge 51 is made of single crystal diamond. Further preferably, in terms of crystallography, the top surface SD1 is a {001} plane, Each of the side faces SD2 and SD3 is a {111} face. In this case, the side faces SD2 and SD3 have different directions, but are crystallographically equivalent to each other.

Further, a diamond which is not a single crystal may be used. For example, a polycrystalline diamond synthesized by a CVD (Chemical Vapor Deposition) method may also be used. Alternatively, a sintered diamond in which polycrystalline diamond particles not containing a bonding material such as an iron group element are bonded by a binder such as an iron group element may be used from graphite or non-graphite carbon.

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

(Method of breaking glass substrate)

Next, a description will be given of a method of dividing the glass substrate 4 with reference to a flow chart shown in FIG.

In step S10 (Fig. 5), the glass substrate 4 (Fig. 1) to be broken is prepared. The glass substrate 4 has an upper surface SF1 (one surface) and an opposite lower surface SF2 (the other surface). An edge ED is provided on the upper surface SF1. In the example shown in Fig. 6, the edge ED has a rectangular shape. The glass substrate 4 has a thickness direction DT perpendicular to the upper surface SF1. Further, in step S20 (Fig. 5), the cutting tool 50 (Figs. 1 and 2) having the blade leading edge 51 is prepared.

Referring to Fig. 6, a groove line TL is formed in step S30 (Fig. 5). Specifically, the following steps are performed.

First, the vertex PP of the blade leading edge 51 (Fig. 1) is pressed against the upper surface SF1 at the position N1. Thereby, the blade leading edge 51 is in contact with the glass substrate 4. Preferably, the position N1 is separated from the edge ED of the upper surface SF1 of the glass substrate 4 as shown. In other words, at the sliding start timing of the blade leading edge 51, the blade leading edge 51 is prevented from colliding with the edge ED of the upper surface SF1 of the glass substrate 4.

Next, the blade leading edge 51 which is pressed as described above is slid on the upper surface SF1 of the glass substrate 4 (see an arrow in Fig. 6). The blade leading edge 51 (Fig. 1) slides on the upper surface SF1 in the direction from the ridge line PS toward the top surface SD1. Strictly speaking, the blade leading edge 51 slides in a direction DB formed by projecting the ridge line PS from the apex PP toward the top surface SD1 toward the upper surface SF1. The direction DB is projected substantially in the direction in which the ridge line PS in the vicinity of the vertex PP is projected to the upper surface SF1. In FIG. 1, the direction DB corresponds to a direction opposite to the direction in which the axial direction AX extending from the blade leading edge 51 is projected onto the upper surface SF1. Therefore, the blade leading edge 51 is pressed into the upper surface SF1 by the shank 52.

Each of the ridge line PS and the top surface SD1 of the blade leading edge 51 (FIG. 1) which slides on the upper surface SF1 of the glass substrate 4 forms an angle AG1 and an angle AG2 with the upper surface SF1 of the glass substrate 4. Preferably, the angle AG2 is smaller than the angle AG1.

Plastic deformation occurs on the upper surface SF1 by the above sliding. Thereby, a groove line TL having a groove shape is formed on the upper surface SF1 (FIG. 7). Preferably, the groove line TL is generated only by plastic deformation of the glass substrate 4, and in this case, no cutting occurs on the upper surface SF1 of the glass substrate 4. In order to avoid cutting, it is sufficient that the load on the leading edge 51 of the blade is not excessively high. Since there is no cutting, it is possible to avoid generation of fine and fine fragments on the upper surface SF1. However, a small amount of cutting is usually allowed.

The groove line TL is formed by sliding the blade leading edge 51 from the position N1 to the position N3e via the position N2 between the position N1 and the position N3e. The position N2 is separated from the edge ED of the upper surface SF1 of the glass substrate 4. The position N3e is located at the edge ED of the upper surface SF1 of the glass substrate 4.

The groove line TL is formed in a non-cracked state, that is, in the groove line Below the TL, the glass substrate 4 is continuously connected in a direction DC (FIG. 7) intersecting with the extending direction of the groove line TL (the horizontal direction in FIG. 6). In the non-cracked state, although the groove line TL formed by plastic deformation is formed, cracks along it are not formed. In order to obtain a proper crack-free state, the load applied to the leading edge 51 of the blade is adjusted so as to be small as to the extent that the groove line TL is formed at a point in time without cracking, and is generated as if it can be produced in a subsequent step. The degree of plastic deformation of the state of the internal stress of the crack.

In order to form the groove line TL, the leading edge 51 of the sliding edge as described above finally reaches the position N3e. When the blade leading edge 51 is at the position N2, the crack-free state is maintained, and the crack-free state is maintained until the blade leading edge 51 reaches the position N3e. If the blade leading edge 51 reaches the position N3e, the ridge line PS (Fig. 1) of the blade leading edge 51 cuts off the edge ED of the upper surface SF1 of the glass substrate 4.

Referring to Fig. 8 and Fig. 9, by the above-described cutting, fine destruction occurs at the position N3e. Starting from this destruction, cracks are generated in such a manner that the internal stress near the groove line TL is released. Specifically, the crack of the glass substrate 4 in the thickness direction DT extends from the groove line TL at a position N3e located at the edge ED of the upper surface SF1 of the glass substrate 4 (refer to an arrow in FIG. 8). In other words, the formation of the crack line CL begins. Thereby, as step S50 (FIG. 5), the crack line CL is formed from the position N3e to the position N1.

Further, in order to make the formation of the crack line CL more certain, the speed at which the blade leading edge 51 slides from the position N2 to the position N3e may be made smaller than the speed from the position N1 to the position N2. Similarly, the load applied from the position N2 to the position N3e to the leading edge 51 of the blade can be made larger than the load from the position N1 to the position N2 in the range of maintaining the crack-free state.

By the crack line CL, under the trench line TL, the glass substrate 4 is The connection of the continuity DC (Fig. 9) in the direction in which the groove line TL extends (the horizontal direction in Fig. 8) is interrupted. Here, "continuous connection" means, in other words, a connection that is not obscured by cracks. Further, in the state in which the continuous connection is interrupted as described above, the portions of the glass substrate 4 may be brought into contact with each other via the crack of the crack line CL. Further, a slight continuous connection may be left immediately below the groove line TL.

The direction in which the crack line CL (Fig. 8) extends along the groove line TL (Fig. 6) (arrow of Fig. 8) is opposite to the direction in which the groove line TL is formed (arrow of Fig. 6). In order to generate the crack line CL by such a directional relationship, it is preferable to make the angle AG2 smaller than the angle AG1 when the blade leading edge 51 is slid in the direction DB (FIG. 1) in order to form the groove line TL. If the angle relationship is not satisfied, the crack line CL is less likely to occur. Moreover, if the angle AG1 and the angle AG2 are substantially the same, whether or not the crack line CL is generated tends to be unstable.

Next, in step S60 (Fig. 5), the glass substrate 4 is separated along the crack line CL. That is, a so-called breaking step is performed. The breaking step can be performed by applying an external force to the glass substrate 4. For example, a stress applying member (for example, a member called a "breaking bar") is pressed against the lower surface SF2 toward the crack line CL (FIG. 9) on the upper surface SF1 of the glass substrate 4, and the crack is opened, for example. The stress of the crack of the line CL is applied to the glass substrate 4. Further, in the case where the crack line CL is completely advanced in the thickness direction DT at the time of its formation, the formation of the crack line CL is simultaneously generated with the division of the glass substrate 4.

The division of the glass substrate 4 is performed based on the above. Furthermore, the step of forming the crack line CL described above is substantially different from the so-called breaking step. The rupture step is to completely separate the substrate by stretching the already formed cracks in the thickness direction. On the other hand, the step of forming the crack line CL is from a crack-free state obtained by the formation of the groove line TL to a crack The change in state. This change is thought to be produced by the release of internal stresses in the crack-free state.

(Comparative Example 1)

Referring to Fig. 10, the apex PP of the blade leading edge 59 of this comparative example is set at a portion where the four faces SE1 to SE4 intersect. The vertices PP are provided with four ridge lines PS1 to PS4. In this case, in the step of FIG. 6, the edge ED of the upper surface SF1 of the glass substrate 4 can be cut by any of the ridge lines PS1 to PS4. Therefore, similarly to the present embodiment, there is an advantage that the crack line CL can be easily formed reliably. On the other hand, the formation of the leading edge 59 requires a high degree of processing accuracy, and therefore has the disadvantage that it is not easy to form. The reason for this is that, in the case where the vertex PP of the blade leading edge is provided in the portion where the surfaces SE1 to SE4 intersect as in the present comparative example, the remaining one must be made by passing the points where the three faces intersect. The position of the face is the same.

(Comparative Example 2)

In the present comparative example, the sliding direction of the blade leading edge 51 is set to be opposite to the direction DB (FIG. 1). In this case, in the step of FIG. 6, the edge ED of the upper surface SF1 of the glass substrate 4 is cut by the top surface SD1 instead of the ridge line PS. That is, in the case of cutting, the sharp ridge line PS acts in the above-described embodiment, whereas in the comparative example, the flat top surface SD1 functions. Therefore, in the comparative example, it is difficult to cause fine breakage which is a trigger for the formation of the crack line CL. Therefore, it is indeed difficult to form the crack line CL.

(Examples and Comparative Example 3)

Fig. 11 is a side view schematically showing the breaking shape of the glass substrate 4 of the embodiment of the embodiment. Fig. 12 is a side view schematically showing the breaking shape of the glass substrate 4 of Comparative Example 3. The thickness of the glass substrate 4 to be divided was set to 0.1 mm. The surface obtained by breaking the glass substrate 4 (hereinafter, also referred to as "cross-section") corresponds to the right side of FIGS. 11 and 12, and is based on the surface distribution obtained by a laser microscope, and emphasizes the height difference of the cross-section. The ridge line PS (Fig. 3) of the blade leading edge 51 used at the time of breaking is assumed to be a non-chamfering process in the embodiment, and is subjected to a chamfering process in Comparative Example 3. The radius of curvature of the ridge line PS was 0.6 μm in the examples and 3.9 μm in the comparative example 3.

The cross-section of the example was better than the cross-section of Comparative Example 3, and the straight angle with respect to the upper surface SF1 was good. Further, the cross-section of the example was superior to the cross-section of Comparative Example 3 in flatness. Specifically, the height difference of the cross-section was 0.5 μm in the examples and 2.3 μm in Comparative Example 3. The term "height difference" as used herein refers to the difference between the lowest position and the highest position in the surface distribution of the sectional section. Thus, it is presumed that the reason why a good cross-section is obtained in comparison with the comparative example 3 is that the internal stress applied to the glass substrate 4 is more locally concentrated when the groove line TL is formed because the radius of curvature of the ridge line PS is small. Give.

(summary of effects)

According to this embodiment, the blade leading edge 51 can be easily prepared. The first reason is that, unlike the first comparative example 1, the apex of the blade leading edge 51 is provided as a portion where the three faces of the top surface SD1, the side surface SD2, and the side surface SD3 intersect. It is assumed that when the apex of the blade leading edge is provided by a portion where more than three faces intersect, it is necessary to make the positions of the remaining faces coincide by the point where the three faces intersect. Therefore, higher processing accuracy is required. On the other hand, when the apex of the blade leading edge is provided by the portion where the three faces intersect, the processing precision is not required to be high. The second reason is that the ridge line PS of the blade leading edge 51 is a person who has not been chamfered. Thereby, the blade leading edge 51 can be easily prepared as compared with the case where the ridge line PS of the blade leading edge 51 is a chamfered processor. If the situation is observed from other viewpoints, the reason is that the blade leading edge 51 has 2 μm in the cross section perpendicular to the ridge line PS. Hereinafter, the radius of curvature of 1 μm or less is preferable. Such a radius of curvature can be easily obtained by controlling the chamfering process with respect to the ridge line PS only after the opposite side of the ridge line PS is formed. Therefore, the blade leading edge 51 can be easily prepared.

Further, according to the present embodiment, the load on the leading edge 51 of the blade can be reduced by using the crack-free scribe technique. Thereby, the sufficient life of the blade leading edge 51 can be ensured while the top surface SD1 is the front side and the ridge line PS is the rear side.

Further, according to the present embodiment, a good cross section is obtained as compared with Comparative Example 3 in which chamfering is performed with respect to the ridge line PS. Specifically, a cross section having a good straight angle with respect to the upper surface SF1 is obtained. Further, a cross section having a good flatness is obtained.

Further, according to the present embodiment, the crack line CL along the groove line TL can be formed more reliably. The first reason is that, unlike the above-described Comparative Example 2, the edge line ED of the upper surface SF1 of the glass substrate 4 is cut by the ridge line PS of the blade leading edge 51 which is slid to form the groove line TL. The second reason is that the ridge line PS thus cut is not chamfered or has a radius of curvature of 2 μm or less, so that it is in a sharp state. The crack line CL can be formed more surely by cutting the edge ED of the upper surface SF1 of the glass substrate 4 by the sharp ridge line PS.

<Embodiment 2>

Referring to Fig. 6, in the present embodiment, a lubricant is supplied to a position where the blade leading edge 51 slides on the upper surface SF1 of the glass substrate 4. In other words, the step of forming the groove line TL (Fig. 6) (Fig. 5: step S30), as shown in Fig. 13, includes the step S31 of supplying the lubricant, and the step of sliding the blade leading edge 51 at the position where the lubricant is supplied. S32. In order to carry out step S31, for example, a lubricant supply unit (not shown) may be provided in the shank 52 (Fig. 1). Incidentally, the configuration other than the above is substantially the same as the configuration of the above-described first embodiment, and thus the description thereof will not be repeated. also, Step S31 can also be applied to the following embodiments 3 to 5.

In the present embodiment, as in the first embodiment, the direction DB (Fig. 1) is selected as the forward direction of the blade leading edge 51. Under the condition that the load on the leading edge 51 of the blade is the same, the sliding in the direction DB is more likely to cause damage to the leading edge 51 of the blade than in the opposite direction. According to this embodiment, the damage can be effectively suppressed. Thereby, the life of the leading edge of the blade can be extended.

<Embodiment 3>

Referring to Fig. 14, in step S10 (Fig. 5), the same glass substrate 4 as in the first embodiment described above is prepared. However, in the present embodiment, the auxiliary line AL is provided on the upper surface SF1 of the glass substrate 4. Referring to Fig. 15, the auxiliary line AL has an auxiliary groove line TLa and an auxiliary crack line CLa. The auxiliary groove line TLa has a groove shape. The auxiliary crack line CLa is formed by extending a crack of the glass substrate 4 in the thickness direction DT along the auxiliary groove line TLa.

In the present embodiment, the auxiliary line AL is provided on the upper surface SF1 of the glass substrate 4 by the step of simultaneously forming the auxiliary groove line TLa and the auxiliary crack line CLa. Such an auxiliary line AL can be formed by a typical typical cutting method. For example, such an auxiliary line AL can be carried out by placing the leading edge of the blade on the edge ED of the upper surface SF1 of the glass substrate 4 and then moving it on the upper surface SF1 as indicated by the arrow of FIG. The fine crack is generated by the impact at the time of the rest, so that the auxiliary crack line CLa can be easily formed simultaneously when the auxiliary groove line TLa is formed. In order to suppress damage to the leading edge of the blade and the glass substrate 4 during the rest, the leading edge of the blade preferably has a shape suitable for rest depending on the shape of the leading edge 51 of the blade. Specifically, the leading edge of the blade is preferably a holder that can be rotated (wheel type). In other words, the leading edge of the blade is preferably rotated on the glass substrate 4 rather than being a slider. Furthermore, the starting point of the auxiliary line AL is the edge ED in FIG. 14, but it can also be separated from the edge ED.

Next, in step S20 (Fig. 5), the blade leading edge 51 similar to that of the first embodiment is prepared. Further, in order to facilitate the preparation of the leading edge of the auxiliary line AL for the blade, the blade leading edge 51 may be used to form the above-described auxiliary line AL. Alternatively, the auxiliary line AL may be formed using a blade leading edge having the same shape as the shape of the blade leading edge 51.

Referring to Fig. 16, second, a groove line TL is formed in step S30 (Fig. 5). Specifically, the following steps are performed.

First, the same operation as in the first embodiment is performed. Specifically, the vertex PP of the blade leading edge 51 (FIG. 1) is pressed against the upper surface SF1 at the position N1. Next, the pressed blade leading edge 51 is slid in the direction DB (FIG. 1) on the upper surface SF1 of the glass substrate 4 (see an arrow in FIG. 16). Thereby, the groove line TL is formed on the upper surface SF1 in a crack-free state.

In the present embodiment, the groove line TL is formed by sliding the blade leading edge 51 between the position N1 and the position N3a from the position N1 to the position N3a via the position N2. The position N3a is arranged on the auxiliary line AL. The position N2 is disposed between the position N1 and the position N3a. Preferably, the leading edge 51 of the blade exceeds the position N3a on the auxiliary line AL and then slides to the position N4. Preferably, position N4 exits from edge ED.

In order to form the groove line TL, the leading edge 51 of the sliding edge as described above intersects the auxiliary line AL at the position N3a. Therefore, the ridge line PS (Fig. 1) of the blade leading edge 51 also intersects the auxiliary line AL. By this intersection, fine destruction occurs at the position N3a. The break is used as a starting point, and a crack is generated in such a manner as to release the internal stress near the groove line TL. Specifically, the crack of the glass substrate 4 in the thickness direction DT extends from the groove line TL from the position N3a located on the auxiliary line AL (refer to the arrow of FIG. 17). In other words, the crack line CL extends along the groove line TL from the auxiliary line AL which is crossed by the ridge line PS of the blade leading edge 51. Thereby, as step S50 (Fig. 5), from position N3a A crack line CL is formed toward the position N1. After the crack line CL is formed, in the same manner as in the first embodiment, the connection of the glass substrate 4 in the direction intersecting the groove line TL is interrupted by the crack line CL.

After the blade leading edge 51 reaches the position N3a, it leaves from the glass substrate 4. Preferably, the blade leading edge 51 is separated from the glass substrate 4 after the position N3a has slid to the position N4.

Next, in step S60 (FIG. 5), the glass substrate 4 is cut along the crack line CL in the same manner as in the first embodiment. Based on the above, the method of dividing the glass substrate 4 of the present embodiment is performed.

According to the present embodiment, as in the first embodiment, the crack line CL along the groove line TL can be formed more reliably. The reason for this is that the ridge line PS of the blade leading edge 51 which slides to form the groove line TL is directed to the auxiliary line AL provided on the upper surface SF1 of the glass substrate 4 and the groove formed by the apex of the leading edge 51 of the sliding blade. The position N3a (Fig. 16) where the line TL intersects locally applies stress. By the application of the stress, the start of the formation of the crack line CL is obtained with higher certainty. Further, substantially the same effects as those of the first embodiment were obtained.

<Embodiment 4>

In the present embodiment, unlike the third embodiment, each of the auxiliary groove line TLa and the auxiliary crack line CLa included in the auxiliary line AL (Figs. 15 and 16) is similar to that described in the first embodiment. It is formed by the method of forming the groove line TL and the crack line CL. Hereinafter, the method will be specifically described.

First, the leading edge of the blade for forming the auxiliary line AL is prepared. The leading edge of the blade may be the same as the leading edge 51 of the blade (Figs. 1 and 2). That is, the formation of the auxiliary line AL and the formation of the groove line TL which is then formed can also be performed by the common blade leading edge 51. Or as a substitute The leading edge of the edge of the auxiliary wire AL can also be prepared with a blade leading edge different from the leading edge 51 (hereinafter referred to as "auxiliary blade leading edge"). The leading edge of the cutting edge may also have the same shape as the leading edge 51 (Figs. 1 and 2). Alternatively, the leading edge of the cutting edge may have a different shape than the shape of the leading edge 51 of the blade. In the case where the leading edge of the auxiliary blade has a shape different from the shape of the leading edge 51 of the blade, it is preferable that the leading edge of the auxiliary blade has a top surface SD1, a side surface SD2, and a side surface SD3 which form the apex PP and the ridge line PS, The difference in shape is caused by the difference in the configuration between the components. Here, the "shape" of the leading edge of the blade is the portion near the vertex PP in the leading edge of the blade, that is, the shape of the portion that acts on the glass substrate 4, and the shape of the portion away from the active portion is usually not important. Hereinafter, in order not to be described again, there is a case where the leading edge of the blade used for forming the auxiliary line AL is simply referred to as a "blade leading edge" regardless of whether it is the leading edge 51 or the leading edge of the auxiliary blade.

Referring to Fig. 18, second, the auxiliary groove line TLa is formed in a crack-free state by a method similar to the formation of the groove line TL (Fig. 6). Referring to Fig. 19, second, the auxiliary trench line TLa along the auxiliary trench line TLa (Fig. 18) is formed by a method similar to the method of forming the crack line CL along the groove line TL (Fig. 8). According to the above, the auxiliary line AL (Fig. 15) is formed.

Next, in the same manner as in the third embodiment, the groove lines TL (Fig. 16) and the crack lines CL (Fig. 17) are formed in steps S30 and S50 (Fig. 5), and in step S60 (Fig. 5), along the cracks. The line CL separates the glass substrate 4. Based on the above, the method of dividing the glass substrate 4 of the present embodiment is performed.

In the present embodiment, the load applied to the blade leading edge 51 at the time of formation of the groove line TL (Fig. 16) is larger than the load applied to the leading edge of the blade when the auxiliary groove line TLa (Fig. 18) is formed. . According to the experimental study by the inventors, by setting the difference in the load as described above, The crack line CL is more reliably produced (Fig. 17).

Preferably, the angle AG2 (Fig. 1) at the time of formation of the groove line TL (Fig. 16) is smaller than the angle AG2 (Fig. 1) at the time of formation of the auxiliary groove line TLA. By using such an angular relationship, in particular, even when the leading edge of the blade for forming the auxiliary groove line TLa is the blade leading edge 51 or the auxiliary blade leading edge having the same shape as the blade leading edge 51 It is also easy to set the difference in the above load. This reason is that, in the case where the shape of the leading edge of the blade is the same, the smaller the angle AG2 is, the larger the load of the groove line TL (or the auxiliary groove line TLA) can be formed without cracking. When the groove line TL is formed, if the angle AG2 is excessively large, it is difficult to simultaneously achieve a load in which the groove line TL is formed in a crack-free state and the load is larger when the auxiliary groove line TLA is formed. On the other hand, when the angle AG2 (FIG. 1) at the time of formation of the groove line TL (FIG. 16) is smaller than the angle AG2 (FIG. 1) at the time of formation of the auxiliary groove line TLA, the formation of the groove line TL At the time, it is easy to use a load with a larger load than when the auxiliary trench line TLA is formed. Therefore, there is no need to worry about applying a blade leading edge design for the high load to the leading edge 51 of the groove line TL, and applying a blade leading edge design for the low load on the leading edge of the auxiliary groove line TLa. Therefore, at the time of forming the auxiliary groove line TLA, the blade leading edge 51 used in the formation of the groove line TL or the auxiliary blade leading edge having the same shape as that of the groove line TL can be used.

When the difference is set to the angle AG2 (FIG. 1) as described above, it is preferable that the leading edge of the blade for forming the auxiliary groove line TLa is different from the leading edge 51 of the blade for forming the groove line TL. , prepare the auxiliary blade leading edge. Thereby, the posture of the blade leading edge 51 can be fixed in the state where the angle AG2 of the blade leading edge 51 is suitable for the formation of the groove line TL. In other words, between the step of forming the auxiliary groove line TLa and the step of forming the groove line TL, the posture adjustment of the blade leading edge 51 for optimizing the angle AG2 is not required.

<Embodiment 5>

Referring to Fig. 20 and Fig. 21, in the present embodiment, the blade leading edge 51 is used for forming the groove line TL, and the auxiliary blade leading edge 51a is used as the fourth embodiment for forming the auxiliary groove line TLA. The leading edge of the auxiliary blade. The shape of the blade leading edge 51 and the shape of the auxiliary blade leading edge 51a are different from each other. For example, in the vicinity of the apex PP (see FIG. 2), each of the blade leading edge 51 and the auxiliary blade leading edge 51a has an angle AP and an angle APa of the ridge line PS of the cross section perpendicular to the ridge line PS, and the angle AP is larger than the angle APa. Incidentally, the configuration other than the above is substantially the same as the configuration of the above-described fourth embodiment, and thus the description thereof will not be repeated.

According to the present embodiment, when the auxiliary groove line TLA is formed and the groove line TL is formed, a blade leading edge having a different shape is used. Therefore, as the shape of the leading edge of the blade, when each of the auxiliary groove line TLa and the groove line TL is formed, a suitable low load and a low load can be used. Therefore, the crack-free state can be more surely obtained when the auxiliary trench line TLA and the trench line TL are formed, and the auxiliary crack line CLa can be more reliably generated from each of the auxiliary trench line TLA and the trench line TL. Crack line CL.

Further, in the above embodiments, the case where the edge of the upper surface SF1 is formed in a rectangular shape is illustrated, but other shapes may be used. Further, the case where the upper surface SF1 is flat is described, but the upper surface may be curved. Further, the case where the groove line TL is linear is described, but the groove line TL may have a curved shape. Further, although the case where the glass substrate 4 is used as the brittle substrate has been described, the brittle substrate may be made of a brittle material other than glass, and may be made of, for example, ceramic, germanium, compound semiconductor, sapphire or quartz.

AG1‧‧‧ angle

AG2‧‧‧ angle

AX‧‧‧ axial

DB‧‧‧ direction

DT‧‧‧ thickness direction

Edge of ED‧‧

PP‧‧‧ vertex

PS‧‧‧ ridgeline

SD1‧‧‧ top surface (1st side)

SD3‧‧‧ side (3rd side)

SF1‧‧‧ upper surface (one side)

SF2‧‧‧ lower surface (the other side)

4‧‧‧Glass substrate (brittle substrate)

50‧‧‧ cutting instruments

51‧‧‧blade front

52‧‧‧ handle

Claims (4)

A method for breaking a brittle substrate, comprising the steps of: a) preparing a brittle substrate having a surface and a thickness direction perpendicular to the one surface; and further comprising the steps of: b) preparing a blade leading edge, the blade leading edge having: a first surface; a second surface adjacent to the first surface; and a third surface formed by a ridge line adjacent to the second surface and each of the first surface and the second surface The ridge line is adjacent to the apex; the ridge line is not chamfered; and further comprising: c) causing the edge of the blade to face the ridge line from the ridge line on the one surface of the brittle substrate Sliding, and forming a groove line having a groove shape on the one surface of the brittle substrate by plastic deformation, wherein the groove line is formed in a non-cracked state, that is, below the groove line, a state in which the brittle substrate is continuously connected in a direction intersecting the groove line; and further comprising the step of: d) extending the crack of the brittle substrate in the thickness direction along the groove line after the step c) And forming a crack line, wherein the fragile substrate is interrupted in a direction perpendicular to the groove line by the crack line; and further comprising the following steps: e) along the crack line The above brittle substrate is separated. A method for breaking a brittle substrate, which has the following steps: a) preparing a brittle substrate having one surface and a thickness direction perpendicular to the one surface; and further comprising the steps of: b) preparing a leading edge of the blade, the leading edge of the blade having a first surface; a second surface, and the first surface And a third surface formed by forming a ridge line adjacent to the second surface and adjacent to each of the first surface and the second surface; the front edge of the blade is The cross section perpendicular to the ridge line has a radius of curvature of 2 μm or less, and further includes the step of: c) sliding the leading edge of the blade toward the first surface from the ridge line on the one surface of the brittle substrate Forming a groove line having a groove shape on the one surface of the brittle substrate by plastic deformation, and the groove line is formed in a non-cracked state, that is, below the groove line, the brittle substrate is a state in which the direction intersecting the groove line is continuously connected; and further comprising the step of: d) extending the crack of the brittle substrate in the thickness direction along the groove line after the step c) a crack line, wherein the brittle substrate is discontinuously connected to the groove line in a direction perpendicular to the groove line by the crack line; and further comprising the following steps: e) along the crack line The above brittle substrate is broken. The method for breaking a brittle substrate according to claim 1 or 2, wherein the step d) comprises the step of: cutting the brittle base by the ridge of the leading edge of the blade which is slid by the above step c) An edge of the one surface of the plate; and the edge of the crack line extending from the edge line by the ridge line of the leading edge of the blade. The method for breaking a brittle substrate according to claim 1 or 2, wherein the step a) comprises the step of forming an auxiliary line, the auxiliary line having: an auxiliary groove line having the one surface of the brittle substrate a groove shape; and an auxiliary crack line formed by extending the crack of the brittle substrate in the thickness direction along the auxiliary groove line; and the step d) includes the step of: sliding the above by the step c) The ridge line of the leading edge of the blade intersects with the auxiliary line provided on the one surface of the brittle substrate; and the crack line extends along the groove line from the auxiliary line intersecting by the ridge line of the blade leading edge .