JP5397403B2 - Scribing wheel and scribing device - Google Patents

Description

  The present invention relates to a scribing wheel and a scribing apparatus having the scribing wheel.

  Conventionally, a scribing wheel (cutter wheel) made of sintered diamond has been known as a tool used for forming a scribe line on a brittle material substrate (for example, a glass substrate).

JP 2009-166169 A

  Here, sintered diamond (PCD) is produced by sintering a mixture of diamond particles, a metal binder, and an additive under an ultra-high pressure and high temperature where diamond is thermodynamically stable. The Therefore, sintered diamond has no cleavage problem, does not have anisotropy in mechanical properties, and has excellent toughness as compared with single crystal diamond.

  However, the mechanical properties of sintered diamond at high temperatures are reduced due to the metal binder contained in the grain boundaries. For example, when the cutting edge of the scribing wheel comes into contact with the brittle material substrate to form a scribe line, the temperature of the cutting edge of the scribing wheel rises. As a result, the grain boundary bond strength of the sintered diamond is lowered, resulting in a problem that mechanical properties such as wear resistance are lowered.

  Therefore, an object of the present invention is to provide a scribing wheel capable of forming a good scribe line on a brittle material substrate, and a scribing apparatus having the scribing wheel.

In order to solve the above-mentioned problem, the invention of claim 1 is a scribing wheel made of polycrystalline diamond, comprising a disc-shaped main body, an annular blade provided on the outer periphery of the main body, A cutting edge provided along the outermost peripheral portion of the blade, the thickness of the blade decreases from the center of the main body portion toward the cutting edge, and the polycrystalline diamond has an average particle diameter of 0.5. Starting from diamond particles of ˜1 (μm) as a starting material, it is directly converted to diamond under ultra-high pressure and high temperature, and is characterized by consisting essentially of diamond.

  The invention according to claim 2 is the scribing wheel according to claim 1, wherein the cutting edge has a plurality of protrusions provided along the outermost periphery.

  The invention of claim 3 is a scribing unit for forming a scribe line on the brittle material substrate by rolling the scribing wheel according to claim 1 or 2 against the brittle material substrate. And a holding unit that moves the held brittle material substrate relative to the scribe unit while holding the brittle material substrate.

According to the first to third aspects of the present invention, the polycrystalline diamond constituting the scribing wheel is obtained by starting with diamond particles having an average particle diameter of 0.5 to 1 (μm) under ultra high pressure and high temperature. Directly converted to diamond and sintered. Polycrystalline diamond consists essentially of diamond.

  Thereby, this scribing wheel made of polycrystalline diamond can not only improve the hardness at normal temperature but also improve the mechanical properties at high temperature. Therefore, it is possible to further extend the life of the scribing wheel.

  In particular, according to the invention described in claim 2, the scribing wheel is formed of polycrystalline diamond, and the hardness of the scribing wheel at normal temperature and the mechanical characteristics of the scribing wheel at high temperature are improved. Therefore, even when a plurality of protrusions are provided on the outermost peripheral portion of the blade edge, it is possible to suppress the loss of each protrusion and achieve a longer life of the scribing wheel.

It is a front view which shows an example of the whole structure of the scribing apparatus in embodiment of this invention. It is a side view which shows an example of the whole structure of the scribing apparatus in embodiment of this invention. It is a front view which shows an example of a structure of the scribing wheel vicinity. It is a bottom view which shows an example of a structure of the scribing wheel vicinity. It is a bottom view for demonstrating a caster effect. It is a side view which shows an example of a structure of a scribing wheel. It is a front view which shows an example of a structure of a scribing wheel. It is an enlarged view of the A part of FIG. It is a figure which shows the other example of the groove shape formed in the blade edge | tip of the scribing wheel. It is a figure which shows the other example of the groove shape formed in the blade edge | tip of the scribing wheel. It is a figure which shows the other example of the groove shape formed in the blade edge | tip of the scribing wheel.

<1. Configuration of scribing device>
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIGS. 1 and 2 are a front view and a side view, respectively, showing an example of the overall configuration of the scribe device 1. 3 and 4 are a front view and a bottom view showing an example of the configuration in the vicinity of the scribing wheel 50. FIG. FIG. 5 is a bottom view for explaining the caster effect.

  The scribe device 1 includes a scribe line (cutting line: vertical crack) on the surface of a substrate 4 (hereinafter, also simply referred to as “brittle material substrate”) formed of a brittle material such as a glass substrate or a ceramic substrate. It is a device to put.

  As shown in FIGS. 1 and 2, the scribing apparatus 1 mainly includes a holding unit 10, a scribing unit 20, an imaging unit 60, and a control unit 90. 1 and the subsequent drawings have an XYZ orthogonal coordinate system in which the Z-axis direction is a vertical direction and the XY plane is a horizontal plane, as necessary, in order to clarify the directional relationship. .

  Here, as shown in FIG. 3, when the scribe line SL is formed on the surface of the brittle material substrate 4 by the scribe device 1, the brittle material substrate 4 has a vertical crack K extending in the vertical direction (Z-axis direction). Occurs (scribe process).

  Then, by applying a stress to the brittle material substrate 4 in which the vertical cracks K are generated (break process), the main surface on the opposite side from the main surface of the brittle material substrate 4 on which the scribe line SL is formed. The method of extending the vertical cracks K and cutting the brittle material substrate 4 is called “cleaving”.

  On the other hand, the vertical crack K is extended from the main surface of the scribe line SL of the brittle material substrate 4 to the main surface on the opposite side only by the scribe process (that is, without executing the break process), and the brittle material substrate 4 is cut. The technique is called “dividing”.

  These cleaving and dividing are cutting methods preferable to grinding cutting using a diamond cutting saw (or wheel) or a diamond dicing saw in that there are no chips.

  Examples of the material of the brittle material substrate 4 that can be cleaved or divided by the scribing method of the present embodiment include glass, ceramic, silicon, sapphire, and the like. In particular, in recent years, the transition from HTCC (High Temperature Co-fired Ceramics) to LTCC (Low Temperature Co-fired Ceramics), which is relatively easy to process, is accelerating as a substrate used in high-frequency modules related to communication equipment. Therefore, the scribing method of the present embodiment is used more and more effectively.

  The holding unit 10 holds the brittle material substrate 4 and moves the held brittle material substrate 4 relative to the scribe unit 20. As shown in FIG. 1, the holding unit 10 is provided on a base 10 a and mainly includes a table 11, a ball screw mechanism 12, and a motor 13.

  Here, the base 10a is formed of, for example, a substantially rectangular parallelepiped stone surface plate, and the upper surface (the surface facing the holding unit 10) is flattened. Thereby, the thermal expansion of the base 10a can be reduced, and the brittle material substrate 4 held by the holding unit 10 can be favorably moved.

  The table 11 sucks and holds the brittle material substrate 4 placed thereon. Further, the table 11 advances and retracts the held brittle material substrate 4 in the direction of the arrow AR1 (X-axis plus or minus direction: hereinafter, also simply referred to as “advance / retreat direction”) and rotates it in the direction of the arrow R1. As shown in FIGS. 1 and 2, the table 11 mainly includes a suction unit 11 a, a turntable 11 b, and a moving table 11 c.

  The adsorption part 11a is provided on the upper side of the turntable 11b. As shown in FIGS. 1 and 2, a brittle material substrate 4 can be placed on the upper surface of the suction portion 11 a. A plurality of suction grooves (not shown) are arranged in a lattice pattern on the upper surface of the suction portion 11a. Therefore, the brittle material substrate 4 is adsorbed to the adsorbing portion 11a by exhausting (suctioning) the atmosphere in each adsorption groove while the brittle material substrate 4 is placed.

  The turntable 11b is provided on the lower side of the suction portion 11a, and rotates the suction portion 11a around a rotation shaft 11d substantially parallel to the Z axis. The moving table 11c is provided below the rotating table 11b, and moves the suction unit 11a and the rotating table 11b along the advancing / retreating direction.

  Therefore, the brittle material substrate 4 sucked and held by the table 11 is moved forward and backward in the direction of the arrow AR1, and is rotated around the rotating shaft 11d that moves as the suction portion 11a moves back and forth.

  The ball screw mechanism 12 is disposed below the table 11 and moves the table 11 back and forth in the direction of the arrow AR1. As shown in FIGS. 1 and 2, the ball screw mechanism 12 mainly has a feed screw 12a and a nut 12b.

  The feed screw 12 a is a rod that extends along the advancing / retreating direction of the table 11. A spiral groove (not shown) is provided on the outer peripheral surface of the feed screw 12a. One end of the feed screw 12a is rotatably supported by the support portion 14a, and the other end of the feed screw 12a is rotatably supported by the support portion 14b. Further, the feed screw 12a is linked to the motor 13, and when the motor 13 rotates, the feed screw 12a rotates in the rotation direction.

  As the feed screw 12a rotates, the nut 12b advances and retreats in the direction of the arrow AR1 due to a rolling motion of a ball not shown. As shown in FIGS. 1 and 2, the nut 12b is fixed to the lower part of the movable table 11c.

  Therefore, when the motor 13 is driven and the rotational force of the motor 13 is transmitted to the feed screw 12a, the nut 12b advances and retreats in the direction of the arrow AR1. As a result, the table 11 to which the nut 12b is fixed advances and retreats in the direction of the arrow AR1 similarly to the nut 12b.

  The pair of guide rails 15 and 16 regulate the movement of the table 11 in the traveling direction. As shown in FIG. 2, the pair of guide rails 15 and 16 are fixed on the base portion 10a with a predetermined distance in the direction of the arrow AR2.

  A plurality of (two in the present embodiment) sliding portions 17 (17a, 17b) are slidable along the guide rail 15 in the direction of the arrow AR1. As shown in FIGS. 1 and 2, the sliding portions 17 (17a, 17b) are fixed at a predetermined distance in the direction of the arrow AR1 at the lower portion of the movable table 11c.

  A plurality of (two in the present embodiment: for convenience of illustration, only the sliding portion 18a is described) sliding portions 18 are slidable along the guide rail 16 in the direction of the arrow AR1. As shown in FIG. 1 and FIG. 2, each sliding portion 18 is fixed at a predetermined distance in the direction of the arrow AR1 at the lower portion of the movable table 11c, similarly to the sliding portion 17 (17a, 17b). .

  As described above, when the rotational force of the motor 13 is applied to the ball screw mechanism 12, the table 11 moves along the pair of guide rails 15 and 16. Therefore, it is possible to ensure straightness of the table 11 in the forward / backward direction.

  The scribing unit 20 presses and rolls a polycrystalline diamond scribing wheel 50 (see FIG. 3) against the brittle material substrate 4 held by the holding unit 10, thereby forming a scribe line on the surface of the brittle material substrate 4. SL is formed. As shown in FIGS. 1 and 2, the scribe unit 20 mainly includes a head unit 30 and a drive unit 40.

  The head unit 30 applies a pressing force (hereinafter, also simply referred to as “scribe load”) to the surface of the brittle material substrate 4 from the held scribing wheel 50 by a lifting / pressing mechanism (not shown). As shown in FIG. 3, the head unit 30 has a holder 35. The holder 35 is an element that holds the scribing wheel 50 rotatably. As shown in FIG. 3, the holder 35 mainly includes a pin 36, a support frame body 37, and a turning portion 38.

  The pin 36 is a rod body that is fixed in a state of being inserted into a through hole 50 a that penetrates the scribing wheel 50. Here, as shown in FIGS. 3 and 4, the through hole 50a extends along a rotation axis 50b substantially parallel to the X axis.

  As shown in FIG. 3, the support frame body 37 is a structure arranged so as to cover both openings (both ends) of the through hole 50 a. The pins 36 protruding from both ends of the through hole 50 a are rotatably installed with respect to the support frame 37. Therefore, the scribing wheel 50 fixed to the pin 36 is rotatable with respect to the support frame 37.

  As shown in FIG. 3, the swivel unit 38 is provided on the upper portion of the support frame 37 and rotates the support frame 37 around a rotation axis 38 a substantially parallel to the Z axis. As shown in FIG. 4, the position of the rotation shaft 38 a of the swivel unit 38 viewed from the lower surface and the installation position 50 c of the holding unit 10 on the brittle material substrate 4 are misaligned.

  As a result, when the traveling direction of the scribing wheel 50 changes from the arrow AR3 (two-dot chain line) direction to the arrow AR4 (solid line) direction as shown in FIG. Torque works. Therefore, the scribing wheel 50 rotates in the arrow R2 direction, and the position of the scribing wheel 50 changes from the two-dot chain line position to the solid line position.

  Thus, even when the traveling direction of the scribing wheel 50 is changed and the attitude of the scribing wheel 50 is shifted by the angle θ1 with respect to the traveling direction, torque in the direction of the arrow R2 acts on the scribing wheel 50. As a result, the scribing wheel 50 turns so that the posture of the scribing wheel 50 and the traveling direction of the scribing wheel 50 are substantially parallel.

  The drive unit 40 reciprocates the head unit 30 provided with the scribing wheel 50 in the direction of the arrow AR2 (Y-axis plus or minus direction: hereinafter, also simply referred to as “reciprocating direction”). As shown in FIG. 2, the drive unit 40 mainly includes a support column 41, a rail 42, and a motor 43. Although FIG. 2 shows an example in which a ball screw is used as the driving means, other means such as a linear motor (linear rail) can also be used.

  A plurality (two in this embodiment) of the columns 41 (41a, 41b) extend in the vertical direction (Z-axis direction) from the base portion 10a. As shown in FIG. 2, each guide rail 42 is fixed with respect to these support | pillars 41a and 41b in the state pinched | interposed between support | pillars 41a and 41b.

  A plurality of (two in this embodiment) guide rails 42 restrict the movement of the head unit 30 in the reciprocating direction. As shown in FIG. 2, the plurality of guide rails 42 are fixed at a predetermined distance apart in the vertical direction.

  The motor 43 is interlocked and connected to a feed mechanism (not shown) (for example, a ball screw mechanism). Accordingly, when the motor 43 rotates, the head unit 30 reciprocates in the direction of the arrow AR2 along the plurality of guide rails 42.

  The scribing wheel 50 is pressed and rolled on the brittle material substrate 4 to form a scribe line SL (see FIG. 3) on the brittle material substrate 4. The detailed configuration of the scribing wheel 50 will be described later.

  The imaging unit 60 images the brittle material substrate 4 held by the holding unit 10. As shown in FIG. 2, the imaging unit 60 has a plurality of cameras 65 (65a, 65b).

  A plurality (two in this embodiment) of cameras 65 (65a, 65b) are arranged above the holding unit 10 as shown in FIGS. Each camera 65 (65a, 65b) captures an image of a characteristic portion (for example, an alignment mark (not shown)) formed on the brittle material substrate 4. And the position and attitude | position of the brittle material board | substrate 4 are calculated | required based on the image imaged with each camera 65 (65a, 65b).

  Here, the “position” of the brittle material substrate 4 refers to an arbitrary position on the brittle material substrate 4 in the absolute coordinate system. The “posture” of the brittle material substrate 4 is the inclination of the reference line of the brittle material substrate 4 with respect to the reciprocating direction of the head portion 30 (for example, one of the four sides when the brittle material substrate 4 is square). Say it.

  Further, in the present embodiment, a square brittle material substrate 4 is used, and among the four corners of the brittle material substrate 4, alignment marks are formed at two adjacent corners. Each alignment mark is imaged by the corresponding camera 65a, 65b, and the position of each alignment mark in the absolute coordinate system is obtained based on these captured images. Based on the positions of these alignment marks, the position and posture of the brittle material substrate 4 are calculated.

  The control unit 90 realizes operation control of each element of the scribe device 1 and data calculation. As shown in FIGS. 1 and 2, the control unit 90 mainly has a ROM 91, a RAM 92, and a CPU 93.

  A ROM (Read Only Memory) 91 is a so-called nonvolatile storage unit, and stores, for example, a program 91a. As the ROM 91, a flash memory that is a readable / writable nonvolatile memory may be used. A RAM (Random Access Memory) 92 is a volatile storage unit and stores, for example, data used in the calculation of the CPU 93.

  The CPU (Central Processing Unit) 93 performs control according to the program 91a of the ROM 91 (control of forward / backward / revolving operation of the holding unit 10 and reciprocating operation of the head unit 30 by the driving unit 40), and the position of the brittle material substrate 4 And data processing such as posture calculation.

For example, the CPU 93
(1) While calculating the position and posture of the brittle material substrate 4,
(2) Based on the calculation results of the position and orientation, the rotating table 11b is rotated and the moving table 11c is moved back and forth, thereby executing the alignment process of the brittle material substrate 4 with respect to the head unit 30.

<2. Configuration of scribing wheel>
6 and 7 are a side view and a front view showing an example of the configuration of the scribing wheel 50. FIG. In the present embodiment, scribing wheel 50 is formed of polycrystalline diamond.

  As shown in FIGS. 3 to 7, the scribing wheel 50 is arranged such that the lower bottom surfaces of the two truncated cones (where the lower bottom surface has a larger area than the upper bottom surface) face each other. It has a shape (an abacus shape). As shown in FIGS. 6 to 8, the scribing wheel 50 mainly has a main body 51, a blade 52, and a blade edge 52a.

  As shown in FIGS. 6 and 7, the main body 51 has a disk shape, and a through hole 50 a that penetrates the main body 51 along the rotation shaft 50 b is provided near the center of the main body 51. Yes. An annular main body 51 is provided on the outer periphery of the main body 51.

  As shown in FIG. 6, the blade 52 is an annular body formed by concentric inner and outer circumferences around the rotation shaft 50 b. As shown in FIG. 7, the blade 52 is V-shaped when viewed from the front. The thickness Tb (see FIG. 7) of the blade 52 along the rotation shaft 50b gradually decreases from the rotation shaft 50b side toward the blade edge 52a.

  The blade edge 52a is provided along the outermost peripheral portion of the blade 52 (that is, the portion of the blade 52 where the distance from the rotation shaft 50b is maximum and the thickness Tb of the blade 52 is minimum). As shown in FIG. 6, each portion of the blade edge 52a has no intentionally formed irregularities, and the distance between each portion of the blade edge 52a and the rotating shaft 50b is the same.

  Then, the scribing wheel 50 rotates on the brittle material substrate 4 in a state in which the blade edge 52 a is in contact, so that a scribe line SL corresponding to the locus of the blade edge 52 a is formed on the brittle material substrate 4.

<2.1. Scribing wheel dimensions>
Here, the outer diameter Dm (see FIG. 7) of the scribing wheel 50 is usually in the range of 1 to 10 (mm), preferably 1 to 5 (mm) (more preferably 1 to 3 (mm)). is there. When the outer diameter Dm of the scribing wheel 50 is smaller than 1 mm, the handleability and durability of the scribing wheel 50 are lowered. On the other hand, when the outer diameter Dm of the scribing wheel 50 is larger than 5 mm, the vertical crack K at the time of scribing may not be formed deeply with respect to the brittle material substrate 4.

  The thickness Th (see FIG. 7) of the scribing wheel 50 is preferably in the range of 0.5 to 1.2 (mm) (more preferably 0.5 to 1.1 (mm)). When the thickness Th of the scribing wheel 50 is smaller than 0.5 mm, workability and handleability may be deteriorated. On the other hand, when the thickness Th of the scribing wheel 50 is larger than 12 mm, the material for the scribing wheel 50 and the cost for manufacturing increase.

  The blade edge angle θ2 (see FIG. 7) of the blade 52 is usually an obtuse angle, preferably in the range of 90 <θ2 ≦ 160 (deg) (more preferably 100 ≦ θ2 ≦ 140 (deg)). The specific angle of the blade edge angle θ2 is appropriately set based on the material and / or thickness of the brittle material substrate 4 to be cut.

<2.2. Materials included in scribing wheel>
The polycrystalline diamond used for forming the scribing wheel 50 is a crystal-type carbon material having a fine crystal grain structure or an amorphous material, which is directly converted to diamond under ultra-high pressure and high temperature. It is. Polycrystalline diamond is substantially composed only of diamond, and no other substance is intentionally added to the polycrystalline diamond.

Examples of the graphite-type carbon material having a fine crystal grain structure include diamond particles having an average particle diameter of 0.5 to 1 (μm). As the graphite type carbon material having an amorphous, amorphous carbon (amorphous Carbon: a-G) , a carbon nanotube (Carbon Nanotube: CNT), fullerene C ₆₀ is like.

  Here, various diamonds (for example, single crystal diamond, sintered diamond, and polycrystalline diamond) that can be used for forming the scribing wheel 50 will be compared.

  First, a comparison between polycrystalline diamond and single crystal diamond will be made. Single crystal diamond has a cleavage property and crystal anisotropy, and is known to have the highest hardness in a specific plane orientation.

  In contrast, polycrystalline diamond has no cleavage problem, does not have anisotropy in mechanical properties, and has excellent toughness as compared with single crystal diamond. Further, the hardness of the polycrystalline diamond is equivalent to the maximum hardness of the single crystal diamond that depends on a specific plane orientation at room temperature. For this reason, the hardness of the polycrystalline diamond in each plane orientation is substantially the same, which is equivalent to the maximum hardness of the single crystal diamond.

  Single crystal diamond is known to induce slip deformation in a specific (111) <110> direction at high temperatures. As a result, single crystal diamond has a problem that the hardness is lowered by heating.

  On the other hand, polycrystalline diamond has a high grain boundary bond strength and has the effect of suppressing crack propagation and the effect of plastic deformation at the grain boundary. Therefore, polycrystalline diamond has excellent hardness characteristics at high temperatures compared to single crystal diamond.

  Next, a comparative study will be made between polycrystalline diamond and sintered diamond. Sintered diamond is produced by sintering a mixture of diamond particles, metal binder, and additives. Therefore, sintered diamond, like polycrystalline diamond, has no cleavage problem, no anisotropy in mechanical properties, and has excellent toughness. .

  However, sintered diamond has a problem that the mechanical properties at high temperatures are lowered due to the binder contained in the grain boundaries.

  For example, in sintered diamond, adjacent diamond particles are bonded by the catalytic action of a metal binder. That is, the sintered diamond is substantially a composite material having a diamond structure formed by this bonding and a metal binding material. Therefore, in some cases, microcracks are generated in the diamond structure due to the difference between the thermal expansion coefficient of the diamond structure and the thermal expansion coefficient of the metal binder. As a result, when the sintered diamond is subjected to a thermal history, the hardness of the sintered diamond is reduced in some cases.

  On the other hand, polycrystalline diamond does not contain a sintering aid and metal binder, and is a single-phase diamond polycrystalline body. Polycrystalline diamond has a structure in which dense diamond particles of several tens of nanometers are firmly and directly bonded to each other. That is, polycrystalline diamond has substantially no inclusions at the grain boundaries and does not have the problem that microcracks are generated due to the inclusions. Therefore, unlike the sintered diamond, the polycrystalline diamond can reduce the problem that the hardness decreases due to the thermal history.

  Thus, polycrystalline diamond has heat resistance in addition to the advantages of single crystal diamond and the advantages of sintered diamond. Thereby, the scribing wheel 50 formed of polycrystalline diamond can not only improve the hardness at normal temperature, but also improve the mechanical characteristics at high temperature. Therefore, the life of the scribing wheel 50 can be further increased.

<3. Scribing wheel molding method>
Here, a method for forming the scribing wheel 50 from polycrystalline diamond will be described. First, in this shaping | molding method, the disk used as a desired radius is first cut out from the polycrystalline diamond made into suitable thickness (0.5-1.2 (mm)).

  Next, the peripheral portion of the disk is cut so that the thickness Tb of the blade 52 along the rotation shaft 50b gradually decreases from the rotation shaft 50b side toward the blade edge 52a. Thus, a V-shaped blade 52 in front view is formed at the peripheral edge of the disk.

<4. Scribing method>
Here, a method of forming the scribe line SL on the brittle material substrate 4 by the scribing wheel 50 will be described.

  In this method, the scribing wheel 50 of the head unit 30 is pressed against the brittle material substrate 4 by a lifting / pressurizing mechanism (not shown). Further, the motor 13 of the holding unit 10 and / or the motor 43 of the driving unit 40 is driven, and the head unit 30 is relatively relative to the brittle material substrate 4 held by the holding unit 10 in the horizontal plane. Moved. Therefore, a desired scribe line SL is formed on the brittle material substrate 4 by the scribing wheel 50, and a vertical crack K is generated.

  Here, the scribe load is preferably in the range of 5 to 50 (N) (more preferably 15 to 30 (N)). Further, the moving speed of the scribing wheel 50 relative to the brittle material substrate 4 (hereinafter also simply referred to as “scribe speed”) is usually 50 to 1200 (mm / sec), preferably 50 to 300 (mm / sec). It is a range. Note that specific values of the scribe load and the scribe speed are appropriately set based on the material and / or thickness of the brittle material substrate 4.

  Further, the following scribe lines SL are formed on the brittle material substrate 4 in accordance with the relative movement of the head portion 30.

  For example, when the motor 13 is driven while the motor 43 is stopped, the holding unit 10 is moved in the forward / backward direction (arrow AR1 direction in FIG. 1) while the head unit 30 is stopped. That is, the head unit 30 moves relative to the brittle material substrate 4 held by the holding unit 10 in the forward / backward direction. Therefore, a scribe line SL (see FIG. 3) is formed on the upper surface of the brittle material substrate 4 along the advance / retreat direction.

  On the other hand, when the motor 43 is driven while the motor 13 is stopped, the head unit 30 is moved in the reciprocating direction (the direction of the arrow AR2 in FIG. 2) while the holding unit 10 is stopped. That is, the head unit 30 moves relative to the brittle material substrate 4 held by the holding unit 10 in the reciprocating direction. Therefore, a scribe line SL (see FIG. 3) along the reciprocating direction is formed on the upper surface of the brittle material substrate 4.

  The operating states of the motors 13 and 43 are as follows: (1) the motor 43 is stopped and the motor 13 is driven; (2) the motor 13 is stopped and the motor 43 is driven. Is changed to the reciprocating direction (second horizontal direction) from the advancing / retreating direction (first horizontal direction) parallel to the brittle material substrate 4 by the caster effect. That is, the direction of the cutting edge 52a of the scribing wheel 50 is changed by 90 degrees while the scribing wheel 50 is in contact with the brittle material substrate 4. Therefore, a substantially L-shaped scribe line SL (see FIG. 3) is formed on the upper surface of the brittle material substrate 4.

  Furthermore, when the motors 13 and 43 rotate simultaneously, the traveling direction of the head unit 30 is inclined with respect to the forward / backward direction (arrow AR1 direction) and the reciprocating direction (arrow AR2 direction). Therefore, a scribe line SL (see FIG. 3) is formed on the upper surface of the brittle material substrate 4 in a state inclined with respect to the forward / backward direction and the reciprocating direction. Furthermore, when the rotation speeds of the motors 13 and 43 are changed, a curved scribe line SL (see FIG. 3) is formed.

  Here, in the present embodiment, generating the vertical crack K (see FIG. 3) in the brittle material substrate 4 so as to form a substantially L-shaped scribe line is also referred to as “L-shaped scribe”.

  In the case of cleaving, (1) the main surface on which the scribe line SL is formed (hereinafter also simply referred to as “formation surface”) among the main surfaces of the brittle material substrate 4 by a break device (not shown). (2) Stress is applied to the main surface opposite to the formation surface. Therefore, the vertical crack K generated in the brittle material substrate 4 in the scribe process extends to the surface opposite to the formation surface, and the brittle material substrate 4 is cut (break process).

  In the case of division, deep vertical cracks K are formed by a scribing process. Therefore, a break device (not shown) is not required, and the brittle material substrate 4 is cut only by a scribe process.

<5. Advantages of scribing wheel in the present embodiment>
As described above, the scribing wheel 50 of the present embodiment is made of polycrystalline diamond, and the polycrystalline diamond uses a fine grain structure or a graphite-type carbon material having an amorphous material as a starting material. It is directly converted to diamond under high pressure and high temperature. Polycrystalline diamond may contain a very small amount of nitrogen or the like, but it consists essentially of diamond, and no other substance is intentionally added to the polycrystalline diamond.

  Thereby, the scribing wheel 50 formed of polycrystalline diamond can not only improve the hardness at normal temperature, but also improve the mechanical characteristics at high temperature. Therefore, the life of the scribing wheel 50 can be further increased.

<6. Modification>
Although the embodiments of the present invention have been described above, the present invention is not limited to the above embodiments, and various modifications can be made.

  (1) In the present embodiment, it has been described that each portion of the blade edge 52a has no intentionally formed irregularities (see FIGS. 6 and 7), but the shape of the blade edge 52a is limited to this. Not a thing. FIG. 8 is an enlarged view of a portion A in FIG. As shown in FIG. 8, the blade edge 52a has a protrusion 54, and the blade edge 52a is provided with a groove 53 and a ridge line 54a.

  The plurality of grooves 53 are dents that are substantially V-shaped when viewed from the side and are formed by a conventionally known processing method such as laser processing, electric discharge processing, or grinding processing. As shown in FIG. 8, the adjacent grooves 53 are formed along the outer periphery of the blade 52 by a desired pitch P.

  However, the scribing wheel 50 of the present embodiment has a small diameter (1 to 5 (mm)) as described above, and processing accuracy is required for forming the groove 53. Therefore, laser processing is recommended as a processing method of the groove 53, and examples of the laser beam used include a YAG high frequency laser, a carbon dioxide gas laser, a green laser, a UV laser, and a femtosecond laser.

  As shown in FIG. 8, the plurality of protrusions 54 are provided along the outermost periphery of the main body 51. More specifically, each protrusion 54 is provided between adjacent grooves 53 among the plurality of grooves 53 provided along the cutting edge 52a.

  Thus, the blade edge 52a has a plurality of protrusions 54 (see FIG. 8), and when the brittle material substrate 4 is cut (divided or cleaved), each protrusion 54 comes into contact with (cuts into) the blade edge 52a. Is realized.

  Further, as described above, the scribing wheel 50 is formed of polycrystalline diamond. Thereby, the hardness of the scribing wheel 50 at normal temperature and the mechanical characteristics of the scribing wheel 50 at high temperature are improved.

  Therefore, even when the advancing direction of the scribing wheel 50 is changed in a state where the scribing wheel 50 is in contact with the brittle material substrate 4 to be cut, each protrusion 54 of the blade edge 52a is lost. Can be effectively prevented. Therefore, the life of the scribing wheel 50 can be further extended.

  In FIG. 8, only three grooves 53 and four protrusions 54 are shown for convenience of illustration. Further, the plurality of grooves 53 formed in the blade edge 52a are intentionally processed by a micrometer order. Therefore, the plurality of grooves 53 are distinguished from the grinding striations inevitably formed by the grinding process at the time of forming the blade edge 52a.

  Further, the depth Dp of the groove 53 formed in the blade edge 52a (in other words, the height of the protrusion 54: see FIG. 8) is usually 1 to 60 (μm), preferably 1 to 20 (μm) (further Preferably, it is the range of 1-15 (micrometer)). When the scribe line SL is continuously formed by the scribing wheel 50 in which the depth Dp of the groove 53 is 1 μm or more (particularly 2 μm or more), the scribe line SL in which the vertical crack K becomes the desired depth or more is formed. A sufficient length (hereinafter simply referred to as “effective cutting length”) can be secured. On the other hand, the depth Dp is set to 60 μm or less from the viewpoint of workability.

  Moreover, the pitch P (refer FIG. 8) between the adjacent groove | channels 53 is 10-200 (micrometer) normally, Preferably, it is the range of 50-200 (micrometer) (more preferably, 70-170 (micrometer)). It is. When the pitch P between the adjacent grooves 53 is smaller than 10 μm, wear of the cutting edge 52a of the scribing wheel 50 is increased, and durability may be lowered. On the other hand, when the pitch P is larger than 200 μm, a good vertical crack K may not be formed on the brittle material substrate 4.

  The length L (see FIG. 8) of the ridge line 54a formed between the adjacent grooves 53 is preferably in the range of 25 to 75 (μm) (more preferably 25 to 75 (μm)). . When the length L of the ridge line 54a is smaller than 25 μm, a sufficient effective cutting length cannot be ensured, resulting in a problem that the life of the scribing wheel 50 is shortened.

  Furthermore, the ratio Rt (= W / L) of the width W of the groove 53 to the length L of the ridge line 54a is usually 0.2 to 5.0, preferably 0.5 to 5.0 (further vertical The range is preferably 1.0 to 3.5 from the point of forming cracks, and preferably 0.5 to 1.0) from the point of view of the quality of the cut section or the divided surface. In this case, a sufficient effective cutting length can be secured.

  (2) Further, the shape of the plurality of grooves 53 provided in the blade edge 52a is not limited to a substantially V shape in a side view. FIGS. 9 to 11 are views showing other examples of the groove 53 formed in the cutting edge 52a of the scribing wheel 50. FIG. As shown in FIG. 9, the groove 53 may be, for example, a trapezoidal depression in a side view. Moreover, as shown in FIG. 10 and FIG. 11, the side view circular arc shape or a rectangular shaped dent may be sufficient.

DESCRIPTION OF SYMBOLS 1 Scribing device 4 Brittle material substrate 10 Holding unit 20 Scribe unit 50 Scribing wheel 51 Main body part 52 Outer peripheral part 52 Blade 52a Blade edge 53 Groove 54 Projection part 90 Control unit K Vertical crack SL Scribe line

Claims (3)

A scribing wheel made of polycrystalline diamond,
(a) a disc-shaped main body,
(b) an annular blade provided on the outer periphery of the main body,
(c) a cutting edge provided along the outermost periphery of the blade;
With
The thickness of the blade decreases from the center of the main body portion toward the blade edge,
The polycrystalline diamond is
Starting from diamond particles having an average particle size of 0.5 to 1 (μm), they are directly converted to diamond under ultra-high pressure and high temperature,
A scribing wheel characterized by consisting essentially of diamond. The scribing wheel according to claim 1,
The cutting edge is
(b-1) a plurality of protrusions provided along the outermost periphery,
The scribing wheel characterized by having. A scribing unit that forms a scribe line on the brittle material substrate by rolling the scribing wheel according to claim 1 or 2 against the brittle material substrate,
A holding unit that moves the held brittle material substrate relative to the scribe unit while holding the brittle material substrate;
A scribing device comprising:

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