JP6413693B2 - Method for dividing brittle substrate - Google Patents

Description

  The present invention relates to a method for dividing a brittle substrate.

  In the manufacture of electrical equipment such as flat display panels or solar cell 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 then the substrate is divided along the scribe line. The scribe line can be formed by mechanically processing the substrate using the cutting edge. When the blade edge slides or rolls on the substrate, a trench due to plastic deformation is formed on the substrate, and at the same time, a vertical crack is formed immediately below the trench. Thereafter, stress is applied, which is called a break process. Thus, the substrate is divided by causing the vertical crack to advance completely in the thickness direction.

  The process of dividing the substrate is relatively often performed immediately after the process of forming a scribe line on the substrate. However, it has also been proposed to perform a process of processing the substrate between the process of forming the scribe line and the break process.

  For example, according to the technique of International Publication No. 2002/104078, in the method of manufacturing an organic EL display, a scribe line is formed on a glass substrate for each region to be each organic EL display before mounting a sealing cap. For this reason, the contact between the sealing cap and the glass cutter, which becomes a problem when the scribe line is formed on the glass substrate after the sealing cap is provided, can be avoided.

  For example, according to the technique of International Publication No. 2003/006391, in a method for manufacturing a liquid crystal display panel, two glass substrates are bonded together after a scribe line is formed. As a result, two brittle substrates can be simultaneously broken in one break step.

International Publication No. 2002/104078 International Publication No. 2003/006391

  According to the above-described conventional technique, the brittle substrate is processed after the scribe line is formed, and then the break process is performed by applying stress. This means that vertical cracks already exist along the entire scribe line during processing into a brittle substrate. Therefore, the further extension in the thickness direction of the vertical crack occurs unintentionally during the processing, and the brittle substrate that should be integrated during the processing may be separated. Also, even when a substrate processing step is not performed between the scribe line formation step and the substrate break step, the substrate is usually transported or stored after the scribe line formation step and before the substrate break step. In this case, the substrate may be unintentionally divided.

  In order to solve the above-mentioned problems, the present inventor has developed a unique cutting technique. According to this technique, as a line that defines a position where a brittle substrate is divided, first, a trench line having no crack is formed immediately below the line. The formation of the trench line defines the position where the brittle substrate will be divided. Thereafter, if a state in which no crack is present immediately below the trench line is maintained, division along the trench line is not easily generated. By using this state, it is possible to prevent the brittle substrate from being unintentionally divided before the time point at which it should be divided, while predefining the position where the brittle substrate is to be divided.

  As described above, the trench line is less likely to break along the scribe line than the normal scribe line. While this is useful in the sense of preventing unintentional fragmentation, it means that special processing suitable for it is required to perform intentional fragmentation. In order to simplify the method of dividing the brittle substrate, it is desirable that this treatment be easy.

  SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and its purpose is to cut a brittle substrate that can be cut along a trench line that does not have a crack directly below it by a simple process. Is to provide.

  The method for dividing a brittle substrate includes the following steps. A brittle substrate provided with a surface having an edge is prepared. Next, the blade edge is moved on the brittle substrate while pressing the blade edge against the brittle substrate. The step of moving the cutting edge is performed by causing the cutting edge to ride on the edge of the brittle substrate, thereby forming a chip at the starting point that is one position on the edge, and the cutting edge that has been mounted on the starting point by the step of forming the chip. Forming a first trench line from a starting point to an ending point which is another position on the surface by generating plastic deformation on the surface of the brittle substrate by moving the cutting edge on the surface while pressing onto the surface of the substrate Including. The step of forming the first trench line is performed so as to obtain a crackless state in which the brittle substrate is continuously connected in the direction intersecting the first trench line immediately below the first trench line. Is called. Next, the brittle substrate is divided along the first trench line by applying a stress to the brittle substrate and extending the crack starting from the chip from the start point to the end point.

  According to the present invention, the chip formed at the edge of the brittle substrate is used as a trigger for extending the crack along the first trench line. This chipping is formed only by the cutting edge moving at the start of the formation of the first trench line riding over the edge of the brittle substrate. Therefore, the brittle substrate can be divided along the first trench line by a simple process.

It is a flowchart which shows schematically the division | segmentation method of a brittle board | substrate in Embodiment 1 of this invention. It is a top view which shows roughly 1 process of the cutting method of the brittle board | substrate in Embodiment 1 of this invention. FIG. 3 is schematic partial cross-sectional views (A) to (C) sequentially illustrating steps of a method for cutting a brittle substrate in the first embodiment of the present invention in a field of view along line III-III in FIG. 2. FIG. 4A is a schematic cross-sectional view taken along line IVA-IVA in FIG. 2, illustrating a configuration of a trench line in a crackless state, and a cross-sectional view illustrating a state in which a crack line is formed immediately below the trench line in a similar field of view. (B). It is a top view which shows roughly 1 process of the cutting method of the brittle board | substrate in Embodiment 1 of this invention. It is a side view which shows roughly the structure of the scribing instrument used for the cutting method of the brittle board | substrate in Embodiment 1 of this invention. It is the front view (A) which shows schematically the structure of the scribing wheel and pin in FIG. 6, and the elements on larger scale (B) of FIG. 7 (A). It is sectional drawing which shows roughly 1 process of the cutting method of the brittle board | substrate in Embodiment 1 of this invention. It is sectional drawing which shows roughly 1 process of the cutting method of the brittle board | substrate in Embodiment 1 of this invention. It is a schematic side view by the visual field corresponding to the arrow X of FIG. It is sectional drawing which shows roughly 1 process of the cutting method of the brittle board | substrate in Embodiment 1 of this invention. It is sectional drawing which shows roughly 1 process of the cutting method of the brittle board | substrate in Embodiment 1 of this invention. It is a top view which shows roughly 1 process of the cutting method of the brittle board | substrate in Embodiment 2 of this invention. It is a top view which shows roughly 1 process of the cutting method of the brittle board | substrate in Embodiment 3 of this invention. It is a top view which shows roughly 1 process of the cutting method of the brittle board | substrate in Embodiment 3 of this invention. It is a top view which shows roughly 1 process of the cutting method of the brittle board | substrate in Embodiment 3 of this invention. It is a partial top view (A)-(D) which shows roughly 1 process of the cutting method of the brittle board | substrate in Embodiment 4 of this invention. 17A is a schematic partial cross-sectional view along line XVIIIA-XVIIIA (A), FIG. 17B is a schematic partial cross-sectional view along line XVIIIB-XVIIIB (B), and FIG. 17C is a line XVIIIC-XVIIIC. FIG. 18 is a schematic partial cross-sectional view (C) taken along line A and a schematic partial cross-sectional view (D) taken along line XVIIID-XVIIID in FIG. The side view (A) which shows roughly the structure of the scribing instrument used for the cutting method of a brittle board | substrate in Embodiment 5 of this invention, and the bottom view of the blade edge | tip by the visual field corresponding to the arrow XIX of FIG. 19 (A) ( B). The side view (A) which shows roughly the structure of the scribing instrument used for the cutting method of the brittle substrate in the modification of the fifth embodiment of the present invention, and the cutting edge according to the field of view corresponding to the arrow XX in FIG. It is a bottom view (B).

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

(Embodiment 1)
FIG. 1 is a flowchart schematically showing a method for dividing a glass substrate 11 (brittle substrate) in the present embodiment. FIG. 2 is a top view schematically showing a state immediately after step S20 (FIG. 1). FIG. 3 is a schematic partial cross-sectional view (A) to (C) showing the steps in order in the field of view along line III-III in FIG.

  First, the glass substrate 11 is prepared (FIG. 1: step S10). The glass substrate 11 has an upper surface SF1 (front 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. In addition, a scribing instrument having a scribing wheel 51R provided with a cutting edge is prepared. Details of the scribing device will be described later.

  Next, the cutting edge contacts the edge EG of the upper surface SF <b> 1 of the glass substrate 11 by the movement of the scribing wheel 51 </ b> R indicated by the arrow M <b> 1 (FIG. 3A). Next, the blade edge is moved on the glass substrate 11 while pressing the blade edge against the glass substrate 11 (FIG. 1: step S20). Hereinafter, the process will be described.

  First, the cutting edge rides on the edge EG of the glass substrate 11 by the movement of the scribing wheel 51R indicated by the arrow M2 (FIG. 3B). Thereby, a chip CP (FIG. 3C) is formed at the start point N1 (FIG. 2) which is one position on the edge EG (FIG. 1: step S20C).

  Next, as shown in the arrow M3 (FIG. 3C), the cutting edge that has run over the starting point N1 in the step of forming the chip CP as described above is pressed onto the upper surface SF1 of the glass substrate 11, and then on the upper surface SF1. The scribing wheel 51R provided with the cutting edge is moved. As a result, plastic deformation occurs on the upper surface SF1 of the glass substrate 11. As a result, a trench line TL (first trench line) is formed from the start point N1 to the end point N3, which is another position on the upper surface SF1 (FIG. 1: step S20T).

  Referring to FIG. 4A, the step of forming trench line TL is a crackless state in which glass substrate 11 is continuously connected in a direction DC intersecting trench line TL immediately below trench line TL. Is done to obtain. In the crackless state, the trench line TL is formed by plastic deformation, but no crack is formed along the trench line TL. Therefore, even if a bending moment is applied to the glass substrate 11, the division along the trench line TL does not easily occur. In order to obtain a crackless state, the load with which the blade edge is pressed against the glass substrate 11 should not be excessively increased. FIG. 4B shows a comparative example of FIG. 4A, and shows a state in which a trench line TL and a crack line CL that is a crack extending directly below the trench line TL are formed.

  A desired number of trench lines can be formed by repeating the process of forming the trench lines TL as necessary. FIG. 2 illustrates a case where three trench lines TL are formed.

  Referring to FIG. 5, a break process is performed next. Specifically, the glass substrate 11 is divided along the trench line TL by applying a stress to the glass substrate 11 to extend a crack starting from the chip CP from the start point N1 to the end point N3 (FIG. 1). : Step S30). The break process can be performed a plurality of times depending on the number of trench lines TL. A more detailed method of the break process will be described later.

  As described above, the glass substrate 11 is divided along the trench line TL.

  Next, the details of the scribing instrument 50R having the above-described scribing wheel 51R will be described with reference to FIGS.

  The scribing instrument 50 </ b> R is attached to a scribe head (not shown) and moves relative to the glass substrate 11 to scribe the glass substrate 11. The scribing instrument 50R includes a scribing wheel 51R, a holder 52R, and a pin 53. The scribing wheel 51R has a substantially disk shape, and its diameter is typically about several millimeters. The scribing wheel 51R is held by a holder 52R via a pin 53 so as to be rotatable around a rotation axis RX.

  The scribing wheel 51R has an outer peripheral portion PF provided with a cutting edge. The outer peripheral portion PF extends in an annular shape around the rotation axis RX. As shown in FIG. 7A, the outer peripheral portion PF stands up like a ridge line at the visual level, thereby forming a cutting edge composed of a ridge line and an inclined surface. On the other hand, at the microscope level, the ridge line of the outer peripheral portion PF has a fine surface shape MS in the portion that actually acts when the scribing wheel 51R enters the glass substrate 11 (below the two-dot chain line in FIG. 7B). Have The surface shape MS preferably has a curved shape having a finite radius of curvature in a front view (FIG. 7B).

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

  Next, a method for using the scribing instrument 50R will be described. The scribing for forming the trench line TL (FIG. 3C) is performed by moving the cutting edge of the scribing instrument 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 due to rolling of the scribing wheel 51R (arrow RT) is the same as the direction of the in-plane component Fi. In other words, the direction in which the trench line TL is formed is the same as the direction of the in-plane component Fi.

  Next, a method particularly suitable for the break process in this embodiment will be described below.

  Referring to FIG. 8, glass substrate 11 (FIG. 2) on which trench lines TL are formed is placed on table 80 via rug 81 so that upper surface SF <b> 1 of glass substrate 11 faces table 80 via rug 81. Placed in. The rug 81 is made of a material that is more easily deformed than the materials of the glass substrate 11 and the table 80.

  With reference to FIGS. 9 and 10, a break bar 85 is prepared. As shown in FIG. 10, the break bar 85 preferably has a protruding shape so as to locally press the surface of the glass substrate 11, and has a substantially V-shaped shape in FIG. 10. As shown in FIG. 9, the protruding portion extends linearly.

  Next, the break bar 85 is brought into contact with a part of the lower surface SF2 of the glass substrate 11. This contact portion is separated from the facing portion SF2C facing the chip CP in the thickness direction (vertical direction in FIG. 9) of the lower surface SF2.

  Next, as indicated by arrow CT1, the contact portion is expanded along the trench line TL and approaches the facing portion SF2C. The break bar 85 comes into contact with the portion facing the trench line TL on the lower surface SF2 and away from the portion facing the chip CP by the first contact described above or subsequent expansion of the contact portion.

  Referring to FIG. 11, as indicated by arrow CT2, the contact portion reaches opposing portion SF2C. In other words, the break bar 85 applies stress to the trench line TL first by the above-described process, and then applies stress to the chip CP at the same time. Due to this stress, a crack extends from the chip CP along the trench line TL (see arrow PR in FIG. 12).

  The glass substrate 11 is divided (FIG. 5) by the above break process.

  According to the present embodiment, the chip CP formed on the edge EG of the glass substrate 11 is used as a trigger for extending the crack along the trench line TL. The chip CP is formed only when the cutting edge that moves at the start of formation of the trench line TL rides over the edge EG of the glass substrate 11. Therefore, the glass substrate 11 can be divided along the trench line TL in a simple process.

  For the formation of the chip CP, the cutting edge of the scribing wheel 51R, that is, the rotating cutting edge is used. Thereby, compared with the case where the fixed blade edge like a diamond point is used, the damage which a blade edge receives when a blade edge rides on the edge EG of the glass substrate 11 is suppressed.

(Embodiment 2)
Referring to FIG. 13, in the present embodiment, a process of forming high load section HR as a part of trench line TL and a process of forming low load section LR as a part of trench line TL are performed. . The high load section HR is formed from the start point N1 to an intermediate point N2 between the start point N1 and the end point N3. The low load section LR is formed from the midpoint N2 to the end point N3. The load applied to the cutting edge in the process of forming the low load section LR is lower than the load used in the process of forming the high load section HR.

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

  According to the present embodiment, the high load section HR that is a portion extending from the chip CP in the trench line TL is formed by plastic deformation due to the high load. Thereby, compared with the case where the whole trench line TL is formed by the plastic deformation by the low load used in the low load section LR, the crack is likely to occur from the chip CP to the trench line TL. Therefore, in the break process (FIGS. 8 to 12), a crack triggered by the chip CP can be generated more reliably. Therefore, the glass substrate 11 can be more reliably divided along the trench line TL using the extension of the crack.

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

(Embodiment 3)
Referring to FIG. 14, first, a trench line TL having a chip CP at the start point and extending to the end point is formed in the direction DL by a method substantially similar to that of the first embodiment.

  Referring to FIG. 15, next, the blade edge is moved in the direction DM on the upper surface SF <b> 1 while pressing the blade edge onto the upper surface SF <b> 1 of the glass substrate 11 by applying a load. Thus, plastic deformation is generated on the upper surface SF1 of the glass substrate 11, whereby a trench line TM (second trench line) is formed between the points T1 and T6. The trench line TM is formed so that a crackless state can be obtained with respect to the trench line TM, as described in the first embodiment with respect to the trench line TL (FIG. 4A).

  A high load section HR is formed as a part of the trench line TM between the points T1 and T2, between the points T3 and T4, and between the points T5 and T6. A low load section LR is formed as a part of the trench line TM between the points T2 and T3 and between the points T4 and T5. The load applied to the cutting edge in the process of forming the high load section HR is higher than the load used in the process of forming the low load section LR. The high load section HR intersects with the trench line TL. The method for forming the trench line TM can be the same as the method for forming the trench line TL.

  Next, the crack is extended along the trench line TL starting from the chip CP by the same break process as in the first embodiment. Thereby, the glass substrate 11 is divided along the trench line TL (FIG. 16). As a result of this division, cracks extend only in the high load section HR of the trench line TM. As a result, a crack line CL is formed along a part of the trench line TM. Specifically, a crack line CL is formed in the high load section HR in a portion between a side newly generated by the division and one of a pair of intermediate points sandwiching the side.

  Note that crack lines CL are unlikely to be formed in a portion between a side newly generated by the division and the other of the pair of intermediate points sandwiching the side, even in the high load section HR. This is because the ease of extension of cracks along the crack line CL is direction-dependent. This direction dependency is presumed to be 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. 4B, the glass substrate 11 is continuously connected in the direction DC intersecting the extending direction of the trench line TM by the crack line CL immediately below the trench line TM. It has been refused. Here, “continuous connection” means a connection that is not interrupted by a crack. In addition, in the state where the continuous connection is broken as described above, the portions of the glass substrate 11 may be in contact with each other through the cracks of the crack line CL.

  Next, by applying stress to the glass substrate 11 by the same break process as in the first embodiment, the crack extends along the low load section LR starting from the crack line CL. Thereby, the glass substrate 11 is divided along the trench line TM. That is, in addition to the division along the trench line TL described above, the division along the trench line TM is further performed.

  According to the present embodiment, substantially the same effect as in the first embodiment can be obtained. Further, the position where the glass substrate 11 is divided can be defined by the trench line TL and the trench line TM intersecting with the trench line TL.

(Embodiment 4)
With reference to FIG. 17 (A) and FIG. 18 (A), the cutting apparatus of the glass substrate 11 in this Embodiment is demonstrated first.

  The cutting device includes a scribing instrument 50 </ b> R, a conveyor 70, a break 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 instrument 50R is fixed to a scribe head (not shown), and scribes the upper surface SF1 of the glass substrate 11 by coming into contact with the glass substrate 11 moved by the conveyor 70.

  The break roller 61 is a member that locally presses the lower surface SF2 of the glass substrate 11 in order to perform a break process. The auxiliary roller 62 is a roller that comes into contact with the glass substrate 11 on the upper surface SF1 that is the opposite surface so that the break roller 61 can be pressed onto the lower surface SF2. The auxiliary roller 62 is disposed at a position different from the break roller 61 in the planar layout (FIG. 17A) so that the glass substrate 11 can be stably bent by being pressed by the break roller 61. Preferably, It arrange | positions so that a break roller may be pinched | interposed in a rotating shaft direction (vertical direction in FIG. 17 (A)).

  In addition, in order to make a figure legible in FIG. 17 (A) and FIG. 18 (A), the conveyor 70 is typically shown with the dashed-two dotted line. The same applies to the other drawings.

  Next, the cutting method by the above-described cutting apparatus will be described below.

  As the conveyor 70 moves in the conveyance direction CV, the glass substrate 11 is conveyed in the conveyance direction CV. Thereby, the cutting edge of the scribing wheel 51R of the scribing instrument 50R rides on the upper surface SF1 from the edge EG of the glass substrate 11. As a result, the chip CP is formed in the edge EG of the glass substrate 11.

  The cutting edge that rides on the upper surface SF1 moves in the direction opposite to the transport direction CV relative to the upper surface SF1 of the glass substrate 11 by moving the glass substrate 11 in the transport direction CV. The relative movement direction of the blade edge with respect to the upper surface SF1 corresponds to the direction DB (FIG. 17A). During this movement, a load is applied to the cutting edge, whereby a high load section HR of the trench line TL having the position of the chip CP as a starting point is formed on the upper surface SF1.

  Referring to FIGS. 17B and 18B, after the glass substrate 11 is further transported, the load applied to the blade edge is made smaller than that in the high load section HR, so that the trench line TL Formation of the low load section LR is started.

  Referring to FIGS. 17C and 18C, when glass substrate 11 is further conveyed, stress is applied to high load section HR provided with chip CP by break roller 61 and auxiliary roller 62. Is done. Thereby, a crack extends from the chip CP, and as a result, a crack line CL is formed in the high load section HR. In FIG. 18C, the crack line CL penetrates the glass substrate 11 in the thickness direction and reaches the lower surface SF2.

  With reference to FIG. 17D and FIG. 18D, when the glass substrate 11 is further conveyed, application of stress to the low load section LR by the break roller 61 and the auxiliary roller 62 is started. The crack extends from the crack line CL described above to the portion of the low load section LR that has been subjected to stress application. Thereafter, as the glass substrate 11 is conveyed, cracks extend in the low load section LR.

  When the crack is extended, the low load section LR is extended by forming the low load section LR by the scribing device 50R. Thereby, the division of the glass substrate 11 proceeds in accordance with the length of the trench line TL extended while the end point of the trench line TL moves away from the starting point. That is, the continuous division of the glass substrate 11 proceeds.

  According to the present embodiment, it is possible to continuously divide the glass substrate 11 using a crack that extends due to the chipping CP. Thereby, the glass substrate 11 can be divided without being restricted by the length of the glass substrate 11.

  In addition, unlike the high load section HR, in the low load section LR, the crack is difficult to extend to a portion where the stress application by the break roller 61 has not yet been received. Therefore, in the continuous cutting step shown in FIG. 18D, it is possible to prevent the crack from reaching the cutting edge and further extending beyond the position of the cutting edge. Thereby, the continuous division | segmentation of the glass substrate 11 can be performed stably.

(Embodiment 5)
Referring to FIGS. 19A and 19B, when the damage when the blade edge rides on the edge EG of the glass substrate 11 is not particularly problematic, a scribing instrument 50 having a fixed blade edge (FIG. 19A). And (B)) may be used.

  The scribing instrument 50 is attached to a scribe head (not shown) and moves relative to the glass substrate 11 to scribe the glass substrate 11. The scribing instrument 50 has a cutting edge 51 and a shank 52. The blade edge 51 is held by the shank 52.

  The blade edge 51 is provided with a top surface SD1 (first surface) and a plurality of surfaces surrounding the top surface SD1. The plurality of surfaces include a side surface SD2 (second surface) and a side surface SD3 (third surface). The top surface SD1 and the side surfaces SD2 and SD3 face different directions and are adjacent to each other. The blade edge 51 has a vertex at which the top surface SD1, the side surfaces SD2 and SD3 merge, and the protrusion PP of the blade edge 51 is configured by this vertex. Further, the side surfaces SD2 and SD3 form ridge lines constituting the side portion PS of the blade edge 51. The side part PS extends linearly from the protrusion part PP. Moreover, since the side part PS is a ridgeline as mentioned above, it has the convex shape extended linearly.

  The cutting edge 51 is preferably a diamond point. That is, the cutting edge 51 is preferably made of diamond. In this case, the hardness can be easily increased and the surface roughness can be decreased. More preferably, the cutting edge 51 is made of single crystal diamond. More preferably, crystallographically, 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 surfaces SD2 and SD3 have different orientations, they are crystal surfaces that are equivalent to each other in terms of crystallography.

  Diamond that is not a single crystal may be used. For example, polycrystalline diamond synthesized by a CVD (Chemical Vapor Deposition) method may be used. Alternatively, polycrystalline diamond sintered from fine graphite or non-graphitic carbon without containing a binder such as an iron group element, or sintered diamond obtained by bonding diamond particles with a binder such as an iron group element May be used.

  The shank 52 extends along the axial direction AX. The blade edge 51 is preferably attached to the shank 52 so that the normal direction of the top surface SD1 is approximately along the axial direction AX.

  In forming the trench line TL using the scribing instrument 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 the direction in which the direction extending along the side part PS from the protrusion PP is projected onto the upper surface SF1, and roughly corresponds to the direction opposite to the direction in which the axial direction AX is projected onto the upper surface SF1. ing.

  Note that when it is not necessary to form the chip CP on the edge EG of the glass substrate 11 as in the formation of the trench line TM (FIG. 15), the blade edge 51 may be slid 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 (the direction opposite to the direction DM in FIG. 15).

  The scribing device 50R and the scribing device 50 may be selectively used by a trench line. In particular, in the third embodiment, the trench line TL may be formed by the scribing instrument 50R, while the trench line TM may be formed by the scribing instrument 50 without causing the blade edge to run.

  With reference to FIG. 20 (A) and (B), the scribing instrument 50v may be used as a modification of this Embodiment. The cutting edge 51v of the scribing instrument 50v has a conical shape having a vertex and a conical surface SC. The protruding part PPv of the blade edge 51v is constituted by a vertex. The side portion PSv of the blade edge is configured along a virtual line (broken line in FIG. 20B) extending from the apex to the conical surface SC. Thereby, the side part PSv has a convex shape extending linearly.

  Although the method for dividing a brittle substrate according to each of the above embodiments is particularly preferably applied to a glass substrate, the brittle substrate may be made of a material other than glass. For example, ceramics, silicon, a compound semiconductor, sapphire, or quartz may be used as a material other than glass.

N1 start point N2 halfway point N3 end point EG edge CL crack line CP chipping SF1 upper surface (surface)
HR High load section SF2 Lower surface LR Low load section TL Trench line (first trench line)
TM trench line (second trench line)
11 Glass substrate (brittle substrate)
50, 50R, 50v Scribing tool 51, 51v Cutting edge 51R Scribing wheel 52 Shank 52R Holder 53 Pin 61 Break roller 62 Auxiliary roller 70 Conveyor 80 Table 81 Rug 85 Break bar

Claims (5)

Preparing a brittle substrate provided with a surface having an edge;
A step of moving the cutting edge on the brittle substrate while pressing the cutting edge against the brittle substrate, and the step of moving the cutting edge,
Forming a chip at a starting point which is one position on the edge by running the blade edge on the edge of the brittle substrate;
Generating plastic deformation on the surface of the brittle substrate by moving the blade edge on the surface while pressing the blade edge that has reached the starting point on the surface of the brittle substrate in the step of forming the chip. Forming a first trench line from the start point to an end point which is another position on the surface, and the step of forming the first trench line is performed immediately below the first trench line. It is performed so as to obtain a crackless state in which the brittle substrate is continuously connected in a direction intersecting the first trench line, and further, stress is applied to the brittle substrate, thereby starting the chip. The brittle substrate is extended along the first trench line by extending the crack from the start point to the end point. A method for dividing a brittle substrate, comprising a step of dividing.   The brittle substrate cutting method according to claim 1, wherein the step of moving the cutting edge is performed using a scribing wheel having an outer peripheral portion around a rotation axis, and the cutting edge is provided on the outer peripheral portion. Forming the first trench line comprises:
Forming a high load section as a part of the first trench line from the start point to an intermediate point between the start point and the end point;
Including a step of forming a low load section as a part of the first trench line from the intermediate point to the end point, and the load applied to the cutting edge in the step of forming the low load section is the high load section The method for dividing a brittle substrate according to claim 1, wherein the method is lower than a load used in a step of forming the substrate. A second trench line is formed by generating plastic deformation on the surface of the brittle substrate by moving the blade edge on the surface while pressing the blade edge onto the surface of the brittle substrate by applying a load. And the step of forming the second trench line is in a state in which the brittle substrate is continuously connected in a direction intersecting the second trench line immediately below the second trench line. The step of forming the second trench line is performed so as to obtain a certain crackless state,
Forming a low load section as part of the second trench line;
A step of forming a high load section as a part of the second trench line, and a load applied to the cutting edge in the step of forming the high load section is a load used in the step of forming the low load section The high load section intersects with the first trench line, and the high load section of the second trench line is triggered by a step of dividing the brittle substrate along the first trench line. Forming a crack line along a portion of the second trench line by extending the crack only in
Dividing the brittle substrate along the second trench line by applying a stress to the brittle substrate and extending the crack along the low load section starting from the crack line. Item 4. The method for dividing a brittle substrate according to any one of Items 1 to 3.   The step of forming the first trench line extends the first trench line when the crack extends in the step of dividing the brittle substrate along the first trench line. Item 4. The method for dividing a brittle substrate according to any one of Items 1 to 3.

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