JP2016210169A - Scribing wheel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a scribing wheel capable of generating a vertical crack nearly from a position, in which the "hook" characteristic is so excellent for a brittle material substrate of a high hardness that a vertical crack can be generated shortly from a position, at which a scribe was started.SOLUTION: An inclined plane having a V-shaped section and made of a single crystal diamond or a polycrystalline diamond is formed on the outer circumference of a scribing wheel, and the arithmetic average roughness Ra of the inclined plane is set at 0.01 μm or less. At the portion of a ridge line 13, in which inclined planes 14a and 14b intersect, there are formed grooves 15a and 15b of a constant pitch less than 8 μm. As a result, the "hook" characteristics can be improved in the scribing wheel made of diamond.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a scribing wheel suitable for scribing a brittle material substrate having high hardness.

  Conventionally, in a manufacturing process of a liquid crystal display panel, a solar cell, or the like, a brittle material substrate dividing process is provided. In the cutting process, the scribing wheel is applied to the surface of the brittle material substrate while applying a load corresponding to various conditions such as the material and thickness of the brittle material substrate to the scribing wheel made of cemented carbide or polycrystalline sintered diamond (PCD). A scribe line is formed by rolling up, and a vertical crack extending from the scribe line in the thickness direction of the brittle material substrate is formed. Then, by applying a predetermined force along the scribe line of the brittle material substrate, the brittle material substrate is divided to manufacture respective panels and glass plates.

  As a result of various improvements in substrate materials and heat treatment processing at glass material manufacturers, when scribing using a scribing wheel (hereinafter also referred to as a normal wheel) equipped with a conventional cutting edge (normal cutting edge) The phenomenon that the cutting edge slips on the substrate surface immediately after the scribing wheel rolls and a scribe line is not formed has been observed.

  Patent Document 1 discloses a scribing wheel having a high penetration effect. This scribing wheel has a large number of notches and protrusions alternately formed in the circumferential direction along a circumferential ridge line having a V-shaped cross section. When this scribing wheel is used, it is possible to form a vertical crack that is relatively deep with respect to the thickness of the glass substrate in the vertical direction from the surface of the glass substrate.

  Such highly penetrating cutting edge scribing wheels are known as “faster” cutting edges than normal cutting edge scribing wheels.

Japanese Patent No. 3074143

  However, when scribing a high-hardness brittle material substrate such as a ceramic harder than a glass substrate, the scribing wheel made of cemented carbide or PCD is composed of a binder such as tungsten carbide or diamond particles and cobalt, so the cutting edge May not be able to form long distance cracks due to chipping or wear. Therefore, when scribing a hard brittle material substrate, a diamond scribing wheel made of a single crystal of a hard material that is harder and more homogeneous than cemented carbide or sintered diamond is preferable. In a diamond material scribing wheel, the cutting edge is mirror-like and the surface roughness of the inclined surface is reduced. For this reason, it is considered that it is more slippery on the substrate, the “hanging” becomes worse, and it becomes difficult to generate a vertical crack immediately after the start of scribing.

  The present invention has been made in view of the problems of such a diamond material scribing wheel, and even when scribing a brittle material substrate using a diamond material scribing wheel, "hanging" is good, An object of the present invention is to provide a scribing wheel that easily generates vertical cracks.

  In order to solve this problem, a scribing wheel of the present invention has a cutting edge having a V-shaped cross section composed of a ridge line made of diamond and a pair of inclined surfaces around a disk, and an arithmetic average of the pair of inclined surfaces. The roughness is 0.01 [mu] m or less, and grooves having a pitch of less than 8 [mu] m are provided on the entire circumference of the ridge line portion of at least one inclined surface of the cutting edge.

  Here, the groove of the scribing wheel may be formed in parallel to the central axis of the disc of the scribing wheel.

  Here, the scribing wheel may be made of single crystal diamond.

  The depth of the groove applied to the ridge line portion of the scribing wheel may be 0.3 μm or less.

  The pitch of grooves applied to the ridge line portion of the scribing wheel may be 1 μm or less.

  In order to solve this problem, the scribing wheel of the present invention has a cutting edge having a V-shaped cross section composed of a ridge line formed of diamond and a pair of inclined surfaces around a disk, and the scribing wheel of the pair of inclined surfaces. Patterning is performed on the entire circumference with an arithmetic average roughness of 0.01 μm or less and a pitch of less than 12 μm and a depth of less than 0.7 μm within a width of 10 μm including the ridge line of at least one inclined surface of the cutting edge. It is a thing.

  Here, the patterning process may be performed such that a convex portion having a curvature radius of 8 to 12 μm is provided on the ridge line in a side view.

  According to the present invention having such a feature, grooving is performed on the entire circumferential portion of the cutting edge of the inclined surface of the scribing wheel, and the groove pitch of the cutting edge is formed with a small pitch of 8 μm or less. For this reason, it is possible to obtain an effect that the substrate has high hardness and can scribe a substrate having high hardness with a deep crack immediately after the start of scribing.

FIG. 1 is a side view and a front view of a scribing wheel according to a first embodiment of the present invention. FIG. 2 is an enlarged side view and front view of the cutting edge portion of the diamond wheel of the present embodiment. FIG. 3 is a perspective view and a side view of the ridge line portion of the cutting edge of the scribing wheel of the present embodiment. FIG. 4 is a side view of the ridge line portion of the cutting edge of a modified example of the scribing wheel of the present embodiment. FIG. 5 is an enlarged side view and front view of a cutting edge portion of a scribing wheel according to a second embodiment of the present invention. FIG. 6 is an enlarged side view and front view of a cutting edge portion of a scribing wheel according to a third embodiment of the present invention.

  Hereinafter, scribing wheels according to embodiments of the present invention will be described in detail with reference to the drawings. The brittle material substrate to be processed in the present embodiment is a SiC substrate having high hardness, but is not limited to this, a glass substrate such as a liquid crystal display panel or a plasma display panel, a single crystal silicon substrate, A brittle material substrate such as a ceramic substrate or a sapphire substrate may be used. Further, “arithmetic average roughness Ra” used in the present specification is one of the parameters representing the surface roughness of industrial products defined in JIS B0601.

  The shape of the scribing wheel according to the first embodiment of the present invention will be described. FIG. 1A is a front view of the scribing wheel according to the present embodiment as viewed from the central axis direction, and FIG. 1B is a side view of the scribing wheel. 2A is an enlarged side view showing the ridge line portion, and FIG. 2B is a front view thereof.

  The scribing wheel 10 of the first embodiment is a disc-shaped wheel formed of single crystal diamond, and supports the scribing wheel 10 at the center of the center shaft 11 as shown in FIGS. 1 and 2. There is a through hole 12 through which a pin (not shown) is inserted. The outer peripheral surface of the scribing wheel 10 is cut out so as to have a V-shaped cross section, a ridge line 13 is formed at the center thereof, and inclined surfaces 14a and 14b are provided on the left and right as illustrated. The inclined surfaces 14a and 14b are formed to have a convergence angle (α). The inclined surfaces 14a and 14b are processed so that the arithmetic average roughness Ra of the inclined surfaces is, for example, 0.01 μm or less. Thus, by reducing the arithmetic average roughness of the inclined surface, the load applied to the substrate during scribing can be concentrated, and the depth of the vertical crack can be made constant. In addition, chipping of the scribe line of the scribing wheel and damage to the substrate can be reduced.

  In the scribing wheel of this embodiment, as shown in FIG. 1, patterning with a constant line pitch P is performed on the entire circumference of the inclined surfaces 14a and 14b including the edge line 13 of the cutting edge within a predetermined width w. It has been done. Here, it is preferable that the patterning process be formed at least in a portion that contacts the substrate at the time of scribing. In the present embodiment, the width w is, for example, 10 to 20 μm. In this patterning process, as shown in enlarged views in FIGS. 2 and 3, a large number of grooves 15a and 15b are formed at a constant pitch P so as to be parallel to the central axis 11 of the disk. The pitch P of the grooves 15a and 15b for patterning is 0.5 μm or more and less than 12 μm, preferably less than 8 μm, more preferably 1 μm or less, and the depth d of the grooves 15a and 15b of the scribing wheel 10 is 0.05 μm or more and 0 or less. Less than 7 μm, preferably 0.3 μm or less.

  By forming such a fine patterning process on both sides of the ridge line 13, a constant friction coefficient can be ensured even for a substrate such as a SiC substrate having a high hardness, and the workability can be improved. In addition, by reducing the depth of the groove, the influence on the scribe quality can be sufficiently reduced.

  The patterning process for the ridgeline and the inclined surface formed of diamond according to the first embodiment can be performed using a surface processing apparatus using a femtosecond laser. A femtosecond laser is a light source whose power is compressed in an extremely short time in units of femtoseconds, and grooves and patterns having a periodic structure can be formed in various materials. Here, as shown in FIG. 2 and FIG. 3, groove processing parallel to the central axis is performed on the inclined surfaces 14 a and 14 b including the ridge line. Then, by appropriately selecting the light source and pulse width of the femtosecond laser, it is possible to perform groove processing with a desired pitch P and depth d.

  The patterning process may be performed so as to include an unprocessed portion in which a ridge line is left between the grooves as in the present embodiment, and as a modified example, as illustrated in FIG. The protrusion 16 having a radius of curvature and the groove 15 therebetween may be provided. The curvature radius R of the convex portion 16 is preferably about 8 to 12 μm.

  In the first embodiment of the present invention, as shown in FIGS. 2 and 3, grooves 15a and 15b having the same length are arranged symmetrically on the inclined surfaces 14a and 14b with respect to the ridge line 13. The lengths of the inclined surfaces 14a and 14b may be different from each other.

  Next, a scribing wheel according to a second embodiment of the present invention will be described. In the present embodiment, the same parts as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted. As shown in FIG. 5, the scribing wheel of the second embodiment is formed by alternately forming grooves 15a and 15b on the entire circumference on inclined surfaces 14a and 14b. Other configurations are the same as those in the first embodiment. In this case, the pitch P of the grooves is the same as that of the first embodiment, and the depth d of the grooves 15a and 15b is also the same as that of the first embodiment. By doing this, the patterning angle with respect to the ridgeline and the inclined surface is reduced, and almost the same effect can be obtained.

  Next, a scribing wheel according to a third embodiment of the present invention will be described. In the present embodiment, the same parts as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted. As shown in FIG. 6, the scribing wheel according to the third embodiment has grooves 15a formed on only one of the inclined surfaces, here the inclined surface 14a. Other configurations are the same as those in the first embodiment. In this case, the groove pitch P is the same as that of the first embodiment, and the depth d of the groove 15a is the same as that of the first embodiment. By doing this, the patterning angle with respect to the ridgeline and the inclined surface is reduced, and almost the same effect can be obtained. In this embodiment, the groove 15b may be formed on the entire circumference only on the other inclined surface 14b.

  The scribing wheel of each embodiment of the present invention has good workability, and can generate a vertical crack immediately after the start of scribing without slipping even on a substrate with high hardness. Therefore, it is possible to obtain an excellent effect that internal scribing can be performed even on a substrate having a high hardness. Further, since no slip occurs, the scribe line of the scribing wheel is uniformly worn, and the life of the scribing wheel can be further extended.

  In each of the embodiments described above, the scribing wheel is made of single crystal diamond, but polycrystalline diamond may be used as the material. In this case as well, a scribing wheel having the same effect can be configured by performing the same groove processing on the ridge line portion of the scribing wheel.

  In each of the above-described embodiments, the entire scribing wheel is made of single crystal diamond. For example, the wheel body made of cemented carbide or the like has a cutting edge made of single crystal or polycrystalline diamond. The present invention can also be applied to a scribing wheel in which a portion is fixed by adhesion or film formation. With such a scribing wheel, it is possible to reduce the use of expensive diamond and to provide an inexpensive scribing wheel.

  The present invention can be applied to a scribing apparatus for scribing a brittle material substrate having high hardness.

DESCRIPTION OF SYMBOLS 10 Scribing wheel 11 Center axis 12 Through-hole 13 Ridge line 14a, 14b Inclined surface 15a, 15b, 15 Groove | groove 16 Convex part

Claims (7)

  There is a cutting edge having a V-shaped cross section composed of a ridge line made of diamond and a pair of inclined surfaces around the disc, and the arithmetic average roughness of the pair of inclined surfaces is 0.01 μm or less, and at least one of the cutting edges A scribing wheel having grooves with a pitch of less than 8 μm in the ridge portion of the inclined surface.   The scribing wheel according to claim 1, wherein the groove of the scribing wheel is formed in parallel to a central axis of a disc of the scribing wheel.   The scribing wheel according to claim 1, wherein the scribing wheel is made of single crystal diamond.   The scribing wheel according to any one of claims 1 to 3, wherein a depth of a groove applied to a ridge line portion of the scribing wheel is 0.3 µm or less.   The scribing wheel according to any one of claims 1 to 4, wherein a pitch of grooves provided on a ridge line portion of the scribing wheel is 1 µm or less.   There is a cutting edge having a V-shaped cross section composed of a ridge line made of diamond and a pair of inclined surfaces around the disc, and the arithmetic average roughness of the pair of inclined surfaces is 0.01 μm or less, and at least one of the cutting edges A scribing wheel in which a patterning process having a pitch of less than 12 μm and a depth of less than 0.7 μm is performed on the entire circumference within a range of 10 μm in width including the ridge line of the inclined surface.   The scribing wheel according to claim 6, wherein the patterning process is performed such that a convex portion having a curvature radius of 8 to 12 μm is provided on the ridge line in a side view.

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