TWI440543B - The inner circumferential processing method of brittle material substrate - Google Patents

Description

Inner circumference processing method of brittle material substrate

The present invention relates to an inner peripheral processing method for cutting a substrate of a brittle material along an inner contour line as an inner circumference. The present invention is applied to, for example, a process of processing a ring-shaped substrate for an information memory device from a square substrate. The substrate referred to herein includes materials such as ceramics, single crystal germanium, semiconductor wafers, and sapphire in addition to the glass substrate.

A glass-made annular substrate for a hard disk or the like is formed by cutting a circular glass substrate into a circular shape.

When the glass substrate is subjected to inner circumferential processing which is cut along a closed curve such as a circle, first, the one-side surface (first surface) of the substrate is used as a circle having an inner contour line, and the left and right edge angles are different. The scribing wheel processes a tangent (line) that is inclined in the depth direction. Next, the surface provided with the tangent is heated and deformed, whereby the crack formed along the tangent penetrates to the opposite side (the second surface). After that, the portion surrounded by the inner contour line is pressed by the pressing member to perform a process of cutting into a circular shape (see Patent Document 1). Further, when an annular glass substrate having an inner circumference and an outer circumference is formed in this manner, first, the cutting process is performed by the above method from the square substrate along the outer contour line of the outer circumference, and then the same method is repeated, and the writing is performed. The inner contour of the circumference is cut to form a ring-shaped substrate. That is, the secondary inner circumference processing is performed.

In addition, when the closed curve shape is cut out from the substrate, the scribing wheel which can cut the tangential line (crack) which can penetrate the crack more than the general scribing wheel (also known as the cutter wheel), A scribing wheel having an inclined groove in which a groove slanting with respect to the axial direction of the cutter wheel is periodically formed has been put into practical use (see Patent Document 2).

Fig. 9 is a view showing the cutting edge of the scribing wheel 22 having the inclined groove. Fig. 9(a) is a front view, Fig. 9(b) is a side view, and Fig. 9(c) is a cross-sectional view taken along line A-A. The inclined groove 22 of the inclined groove is such that the cut surface 22b of the groove 22a is inclined with respect to the axis 22c so that the amount of cut is not uniform on both sides of the ridge line.

Specifically, the groove diameter of 1 to 20 mm is set to be in the range of 20 μm to 200 μm. Further, as shown in FIG. 9(c), h1 is set to 2 μm to 2500 μm and h2 is set to 1 μm to 20 μm for the left and right groove depths h1 and h2.

By using a scribing wheel of such a special cutting edge (referred to as a high-permeability cutting edge), it is possible to form a crack that penetrates to a depth that is virtually unreachable by a generally grooveless scribing wheel.

Further, as a processing method of the annular processed article using the above-described high-permeability cutting edge, it has been disclosed that an annular region outside the inner contour line is heated, and a nozzle for jetting the refrigerant is brought close to a central portion of the inner side of the inner contour line. On the upper side, the refrigerant is sprayed from the nozzle to the central region to be cooled and contracted, whereby a center cutting process for separating the center region is performed (see Patent Document 3).

Further, as an auxiliary means for separating the center region by cooling only by the refrigerant, the nozzle is lowered to forcibly separate the center region, and the nozzle tip abuts against the center region and is pressed to make it mechanical. The method of separation.

Advanced technical literature

[Patent Document 1] Japanese Patent No. 2785906

[Patent Document 2] Japanese Patent No. 2989602

[Patent Document 3] JP-A-2009-190905

In the inner peripheral processing of the inner central region of the cut inner contour line (closed curve), it is necessary to not only surely separate the center region, but the excellent separation surface processing quality is very important.

According to Patent Document 3, a center cutting method for ejecting a refrigerant from a refrigerant ejection nozzle disposed above a central region toward a central region is widely used as a center cutting process for a glass substrate having a thickness of about 0.5 mm to 2 mm. It is regarded as a reliable processing method when it is used, especially in the cutting process of the inner circumference of the diameter of 20 mm.

However, in the inner peripheral processing of an annular glass substrate for a hard disk or the like, it is desirable to cut the diameter smaller than the present diameter for the diameter of the inner circumference to be cut, and specifically, it is required to be, for example, 15 mm or less. Preferably, the inner diameter is processed to a diameter of about 9 mm.

In general, the larger the area of the center area to be cut in the inner circumference processing, the larger the weight of the center area itself, and the easier separation. Therefore, if the diameter of the center area is about 20 mm, the refrigerant is previously formed only by the nozzle. The contraction effect can be surely separated.

However, when the diameter of the inner circumference is as small as about 15 mm, the cooling using only the refrigerant injection may cause a situation in which separation cannot be completely performed. Therefore, in the past, it has been common to lower the nozzle to abut against the center area and press for forced separation.

In this case, if the pressing force at the time of the nozzle abutting on the substrate is increased or the nozzle is brought into contact with the substrate in an instant, the center region can be surely separated, but the gap is formed on the separation surface (inner peripheral surface). There is a problem with the quality side.

Accordingly, an object of the present invention is to provide an inner peripheral machining method capable of reliably separating a center region and preventing a gap from being formed on the separation surface when the inner circumference of the inner contour line (closed curve) is cut.

In order to solve the above problems, the inner peripheral processing method of the brittle material substrate of the present invention is constituted by the following steps: (a) using the edge line of the edge of the scribing wheel to form a direction perpendicular to the axis of the scribing wheel a scribing wheel of the inclined groove, a scribing step of forming a scribe line as an inner contour line of the inner circumference on the first surface of the brittle material substrate; (b) for non-contact with a central area inside the inner contour line a step of pressurizing the substrate to support the substrate and applying a pressure to the central region; and (c) cooling the central region to contract to separate the central region of the central region in a pressurized state .

Here, the inner circumferential processing method described above can be applied to a circular shape in which the inner contour line has a diameter of 15 mm or less.

According to the present invention, in the scribing step, first, the scribing wheel having the inclined groove is rolled to form the first surface of the single side surface of the brittle material substrate, and the oblique crack is formed by the deep penetration in the depth direction (the thickness direction of the substrate). A scribe line is formed as an inner contour of the inner circumference. The oblique crack is formed so as to expand outward in the depth direction from the first surface side. The scribing formed by using the scribing wheel having the inclined groove may have a relative substrate thickness of, for example, 30% or more, preferably 40% or more, more preferably 50% or more (generally 80% or more). Deep cracks.

Next, in the pressurizing step, the substrate on which the inner contour line is formed is placed on the sheet provided with the hole to support the substrate. By arranging the hole of the plate to be non-contact with the central region inside the inner contour line, the central region can be separated through the hole.

Next, pressure is applied to the central region of the substrate supported by the sheet. Although it is only necessary to press the center region with the pressing member, the pressure point is such that the center region is not separated in the state where the pressure is applied, so that the pressing force is suppressed to be low. That is, in the next step, the stage before the cooling of the central region is performed to contract, the state in which the center region is first pressurized and the positive cooling is not performed is performed.

Next, in the center cutting step, the central region is cooled in a pressurized state to contract. As a result, the central region is sufficiently cooled and penetrates obliquely, and when the back surface is reached, since the central region is pressed, the central region is immediately separated.

As described above, by first applying pressure to the central region and then cooling the central region, it is possible to avoid the occurrence of a gap by a strong pressing force or an instantaneous pressing force in a state where the cooling is insufficient. In the case of failure, the inner circumference processing with excellent processing quality is performed.

Means and effects to solve other problems

In the pressurizing step of (b) of the above invention, the heating means provided on the sheet may heat the outer side region of the inner contour line.

In this way, since the temperature difference between the central region and the outer region can be increased, the oblique crack is easily infiltrated, and the separation can be performed more reliably.

In the pressurizing step of (b) of the above invention, the pressurization of the central region may be performed by pressing the metal member forming the inflow path of the cooling medium to the central region to impart pressure; in the center cutting step of (c) The cooling of the central region can be carried out by introducing a cooling medium into the inflow path of the cooling medium of the metal member.

In this manner, the cooling medium is pressed in a state where the cooling medium is not introduced into the metal member, and after the pressing, the cooling medium is introduced into the inflow path of the metal member, that is, it can be cooled in the normal state of the first pressurization.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. Here, the inner peripheral processing of the inner circumference of the disk-shaped glass substrate G and the inner circumference of 15 mm is cut out as an example.

Such inner peripheral processing is suitable for the production of, for example, a glass-made annular substrate for a hard disk.

Fig. 1 is a schematic view showing the overall configuration of a processing system MS1 suitable for the processing method of the present invention. The processing system MS1 is composed of a substrate loading unit 1, a scribing device 2, a breaking device 3, a substrate carrying unit 4, and a transfer robot 5.

The substrate carrying unit 1 is provided with a housing cassette for housing the substrate G, and a plurality of sheet substrates G before the inner circumference processing is carried in.

The scribing device 2 forms a scribe line as an inner contour line on the substrate G using the scribing wheel 22 having the inclined groove shown in FIG. Here, a circle of 15 mm is engraved on the first surface of the substrate G as an inner contour line. The specific configuration of the scribing device 2 will be described later.

The breaking device 3 cuts off the inner center region of the inner contour line on the substrate G on which the inner contour line is formed. The specific configuration of the breaking device 3 is also left to be described later.

The substrate carrying-out unit 4 is provided with a storage cassette that houses the substrate G similarly to the substrate loading unit 1 and carries out the substrate G that has been subjected to the center cutting process.

The transport robot 5 transports the robot arm that is equipped with the vacuum suction mechanism at the tip end at a time, and transports the components between the substrate loading unit 1, the scribing device 2, the breaking device 3, and the substrate carrying unit 4.

Next, the scribing device 2 will be described. The figure shows a schematic configuration of a scribing device.

The scribing device 2 has a loading table 11 and a scribe line 12. The loading table 11 includes a rotating table 13, a rotation driving mechanism 14, a Y stage 17 on which an X stage is mounted, and a Y stage driving mechanism 18, and the substrate G rotatably mounted on the rotating table 13 is moved in the XY direction to be relatively The scribing head 12 moves the substrate G.

The scribing head 12 is provided with a scribing wheel 22 (high-permeability cutting edge) having an inclined groove, and a wheel support for adjusting the crimping load of the scribing wheel 22 having the inclined groove to the substrate G loaded on the rotary table 13 The mechanism 23 and the mechanical arm 24 that adjusts the position of the wheel support mechanism 23 and the scribing wheel 22 having the inclined groove are formed.

The scribing wheel 22 having an inclined groove (see Fig. 9) is periodically formed with a groove 22a inclined with respect to the axial direction of the scribing wheel along the edge ridge line of the scribing wheel 22. Since the groove is formed in the edge ridge line, the penetration depth of the crack in the thickness direction is deeper than in the case of using the grooveless edge, and further, by forming the groove to be inclined with respect to the axis, the crack formed can be inclined. To the crack.

By using the scribing wheel 22 having the inclined groove, if the thickness of the glass substrate is about 2 mm, cracks (line) having a depth of 50% or more deep can be easily formed. . Further, as shown in the following, in the rolling direction of the scribing wheel 22, in order to make the inner side of the closed curve fall when the inner contour line (closed curve) is cut off, the center cut can be performed, so that the crack penetrates further toward the outer side in the depth direction. The direction of expansion is inclined. Specifically, the scribing wheel 22 is rolled toward the outer side of the closed curve toward the outer side of the closed curve, so that the crack is inclined in the direction in which the outer side of the closed curve is expanded as it penetrates in the depth direction.

The wheel support mechanism 23 incorporates a pressing load adjusting mechanism (not shown) using a spring, and can adjust the penetration depth of the crack formed on the substrate G by adjusting the pressure contact between the substrate G and the scribing wheel 22 having the inclined groove. .

The robot arm 24 is supported by the frame 25 and is movable together with the X stage drive mechanism 16 and the Y stage drive mechanism 18 to adjust the position of the scribing wheel 22 having the inclined groove to the loading table 11. That is, the position of the scribing wheel 22 having the inclined groove is adjusted by the mechanical arm 24, and by rotating the rotary table 13, a circle having a desired diameter (inner outline) can be scored on the substrate G. Further, by bringing the X stage 15 and the Y stage 17 of the loading table 11 in parallel, it is possible to move to a position where the substrate G can be received between the transfer robot 5 (see FIG. 1).

Next, the breaking device 3 will be described. FIG. 3 is a view showing a schematic configuration of the breaking device 3.

The breaking device 3 is composed of an annular plate 42 and a center cutting mechanism 43. 4 is a view showing a configuration of an annular plate, and FIG. 4(a) is a perspective view and FIG. 4(b) is a cross-sectional view.

A plurality of suction holes 47 are formed in the upper surface 46 of the annular plate 42 surrounded by the inner circumference and the outer circumference, and can be fixed when the substrate G is loaded. A heater 48 is housed inside the annular plate 42 for heating the area of the mounted substrate G that is in contact with the upper surface 46.

In the center of the annular plate 42, in order to allow the central region G0 (a circular plate having a diameter of 15 mm) to be cut off from the substrate G to be dropped when separated, a hole 49 having a larger diameter than the largest diameter of the central portion G0 is formed. In other words, a hole 49 as an inner peripheral surface having a diameter of 20 mm was formed.

The center cutting mechanism 43 is an air ejector 51 that supplies cooled air (refrigerant) through a supply line (not shown), a nozzle 52 that sprays the cooled air, and a holder 53 that supports the air ejector 51 and the nozzle 52. And an elevating mechanism 55 that moves the holder 53 up and down by the robot arm 54. The front end portion of the nozzle 52 is formed of a resin (for example, Teflon (registered trademark) resin) which is softer than the substrate G to prevent damage of the substrate G when the nozzle 52 abuts against the substrate G. Further, the diameter d of the tip end of the nozzle 52 is formed to be smaller than the diameter D of the center region G0 of the substrate G. Thus, only the center region G0 of the substrate G mounted on the annular plate 42 can be pressed downward with the front end of the nozzle 52. Further, a buffer mechanism is housed in the holder 53, and when the nozzle 52 abuts against the substrate G, a predetermined pressing force is not applied to the substrate G.

Next, the procedure of the inner circumference method of the present invention using the scribing device 2 and the breaking device 3 of the above-described processing system MS1 will be described with reference to the drawings.

First, as shown in FIG. 6, the substrate G conveyed from the substrate loading unit 1 to the rotary table 13 of the scribing device 2 is formed as an inner contour line on the first surface of the substrate G by the scribing wheel 22 having the inclined groove. Within the circumference of C1. At this time, an oblique crack which can penetrate to the thickness of the substrate sheet by half and expand outward in the depth direction is formed.

Next, as shown in FIG. 6, the substrate G is carried from the scribing device 2 to the breaking device 3, and is placed on the annular plate 42. At this time, the position of the central axis of the annular plate 42 and the substrate G is aligned so that the central region G0 of the substrate G is positioned on the hole 49, and the substrate G is loaded by the transport robot 5.

Further, the annular plate 42 sets the temperature so that the central region G0 does not suddenly fall from the substrate G. That is, if the overheating occurs, the oblique crack will penetrate to the back surface and be completely separated at this stage, so the temperature setting must avoid this. When the substrate G is thin, it may not be heated.

Next, as shown in FIG. 7, the refrigerant J is ejected from the nozzle 52 in a state where the pressure W is applied to cool the central region G0.

As a result, the center region G0 shrinks due to the cooling action, and the oblique crack penetrates. Soon after, the central region G0 is separated when the oblique crack reaches the back. In this way, there is no case where the separation is forcibly performed with an impact pressure in a state where the cooling is insufficient, so that separation without causing a notch on the inner peripheral surface can be performed.

In the above-described embodiment, the nozzle 52 for ejecting the refrigerant is lowered to apply the pressure W to the center region. However, a rod-shaped pressing member different from the nozzle 52 may be separately provided to apply the pressure.

Further, in the above embodiment, the refrigerant injection nozzle is used as the cooling means, but the Peltier element may be used for cooling.

Further, in the above embodiment, the inner circumference processing is performed to a diameter of about 15 mm, but the inner circumference processing of the smaller diameter may be performed. For example, it has been confirmed that the inner circumference processing can be performed with high reliability even at a level of 0.9 mm.

Further, the inner circumference processing is not limited to a circular shape, and may be an ellipse or other closed curve.

Industrial availability

The present invention can be utilized in the inner peripheral processing for cutting a brittle material substrate such as a glass substrate by circular or the like.

1. . . Substrate loading unit

2. . . Scribing device

3. . . Fracture device

4. . . Substrate carry-out

5. . . Transport robot

11. . . Loading station

12. . . Dash head

13. . . Rotary table

14. . . Rotary drive mechanism

15. . . X stage

16. . . X stage drive mechanism

17. . . Y stage

18. . . Y stage drive opportunity

twenty two. . . Dash wheel with inclined groove

22a. . . groove

22b. . . Cut surface

22c. . . Axis

twenty three. . . Wheel support mechanism

24, 54. . . Robotic arm

25. . . frame

42. . . Annular plate

43. . . Central resection mechanism

46. . . Above the substrate

47. . . Adsorption hole

48. . . Heater

49. . . hole

51. . . Air ejector

52. . . nozzle

53. . . Holder

55. . . Lifting mechanism

C1. . . Inner circumference

d. . . Diameter of the front end of the nozzle

D. . . Diameter of the central area

G. . . Substrate

G0. . . Central region

J. . . Refrigerant

MS1. . . Processing system

Fig. 1 is a view showing the entire configuration of an example of a processing system for carrying out the processing method of the present invention.

Fig. 2 is a view showing the configuration of a scribing device in the processing system of Fig. 1.

Figure 3 is a diagram showing the construction of a breaking device in the processing system of Figure 1.

Fig. 4 is a view showing the configuration of an annular plate of the breaking device of Fig. 3.

Fig. 5 is a view showing a processing state using a scribing device.

Fig. 6 is a view showing a state of processing using one of the breaking devices.

Fig. 7 is a view showing a state of processing using one of the breaking devices.

Fig. 8 is a view showing a state of processing using one of the breaking devices.

Fig. 9 is a view showing a cutting edge of a scribing wheel having an inclined groove.

C1. . . Inside contour

G. . . Brittle material substrate

G0. . . Central region

42. . . Plate

49. . . hole

Claims (5)

A method for processing an inner circumference of a brittle material substrate is composed of the following steps: (a) using a scribing wheel which is periodically formed with a groove inclined with respect to the axial direction of the scribing wheel at a cutting edge line of the scribing wheel, a scribing step of forming a scribe line as an inner contour of the inner circumference on the first surface of the brittle material substrate; (b) supporting the sheet having a hole for non-contact with a central region inside the inner contour line a substrate, and a pressurizing step of applying a pressure to the central region; and (c) a central cutting step of cooling the central region to contract to separate the central region in a pressurized state. The inner peripheral processing method of the brittle material substrate according to the first aspect of the invention, wherein the inner contour line has a circular shape with a diameter of 15 mm or less. An inner peripheral processing method for a brittle material substrate according to claim 1 or 2, wherein in the pressurizing step of (b), a heating mechanism provided on the sheet heats an outer side region of the inner contour line. An inner peripheral processing method for a brittle material substrate according to claim 1 or 2, wherein in the pressurizing step of (b), the pressurization of the central region is performed by an inflow path in which a cooling medium is formed. The metal member is pressed against the central region to impart pressure; in the central cutting step of (c), the cooling of the central region is performed by introducing the inflow path of the cooling medium of the metal member into the cooling medium. An inner peripheral processing method for a brittle material substrate according to claim 3, wherein in the pressurizing step of (b), the pressurization of the central region is performed by a metal member in which an inflow path of a cooling medium is formed. Pressing in the central region to impart pressure; in the central cutting step of (c), the cooling of the central region is performed by introducing the inflow path of the cooling medium of the metal member into the cooling medium.