JP5383268B2 - Manufacturing method of disk-shaped substrate - Google Patents

Description

  The present invention relates to a method for manufacturing a disk-shaped substrate such as a glass substrate for a magnetic recording medium.

  In response to the increasing demand for recording media, the manufacture of disk substrates, which are disk-shaped substrates, has recently become active. As a magnetic disk substrate which is one of the disk substrates, an aluminum substrate and a glass substrate are widely used. This aluminum substrate is characterized by high workability and low cost, and one glass substrate is characterized by excellent strength, surface smoothness and flatness. In particular, recently, the demand for miniaturization and high density of the disk substrate has been remarkably increased, and the degree of attention of the glass substrate capable of achieving high density with small roughness of the surface of the substrate has increased.

In the manufacturing process of such a disk-shaped substrate, the disk-shaped substrate is accommodated in the opening of the carrier, and grinding using an upper grinding surface plate and a lower grinding surface plate may be performed.
By the way, various improvements have been proposed for this grinding process. As a conventional technique described in the publication, for example, an annular groove is provided in the inner wall portion of the storage hole provided in the carrier plate, and this groove is filled with a soft resin. The technique which performs is proposed (for example, refer patent document 1).
Further, for example, a ring-shaped buffer member made of a resin material softer than the material of the glass substrate is fitted over the entire inner peripheral surface of the work holding hole of the carrier, and the workpiece is positioned in a space surrounded by the buffer member. The technique to make is proposed (for example, refer patent document 2).

JP 2000-280167 A JP 2000-198064 A

By the way, when grinding a disk-shaped substrate using a carrier, it is necessary to set the disk-shaped substrate with respect to the opening provided in the carrier. At this time, the carrier and, for example, the outer peripheral portion of the disk-shaped substrate are in contact with each other. However, scratches may occur on the carrier and the disk-shaped substrate. Further, the setting of the disk-shaped substrate in the opening may be performed by sliding the disk-shaped substrate in surface contact with the surface of the carrier toward the opening. In this case as well, the surface of the carrier and the disc-shaped substrate may be damaged.
An object of the present invention is to reduce scratches and the like that occur when a disk-shaped substrate is set.

For this purpose, the disk-shaped substrate manufacturing method to which the present invention is applied is a disk-shaped substrate in which a carrier is placed on the lower polishing surface plate of a pair of upper and lower grinding surface plates, and the disk-shaped substrate is set in the opening of the carrier. A method of manufacturing a disk-shaped substrate in which the front and back surfaces of a substrate are ground with a pair of grinding surface plates, wherein an opening is formed corresponding to the opening of the carrier, and the flexibility is higher than that of the carrier. The removable carrier adapter is positioned on the carrier so that the opening of the carrier adapter and the opening of the carrier overlap with each other, the surface of the carrier is covered with the carrier adapter, and then the disc is inserted through the opening of the carrier adapter. The substrate is set in the opening of the carrier.

Here, key catcher rear adapters and carrier may be characterized by having an index portion indicative of the time of positioning. Further, the carrier index portion is provided on the outer peripheral side of the carrier formed in a disk shape, and the carrier adapter index portion is provided on the outer peripheral side of the carrier adapter formed in a disk shape. It can be.

Here, the carrier adapter may be characterized in that a ring-shaped member into which the user's finger can be inserted when the carrier adapter is removed from the carrier by the user is attached.
From another point of view, the manufacturing method of the disk-shaped substrate to which the present invention is applied is such that the carrier is placed on a pair of upper and lower grinding surface plates, and the disk-shaped substrate is set in the opening of the carrier. Is manufactured using a pair of grinding surface plates, and the carrier surface is coated with a carrier adapter that can be attached to and detached from the carrier, and then the disk-shaped substrate is attached to the opening of the carrier. And a step of removing the carrier adapter from the carrier before the lapping step or the polishing step.

  ADVANTAGE OF THE INVENTION According to this invention, when setting a disk shaped board | substrate to a carrier, it becomes possible to reduce the damage | wound which arises in a carrier.

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings.
FIGS. 1-1 (a) to (d) and FIGS. 1-2 (e) to (h) are diagrams showing a manufacturing process of a disk-shaped substrate (disk substrate) to which the present embodiment is applied.

(Primary lapping process)
FIG. 1-1 (a) shows the primary lapping process. In this step, first, lapping is performed by the lapping machine 40, and the surface 11 of the workpiece 10 which is a raw material of the disk-shaped substrate is ground smoothly. The wrapping machine 40 includes a lower surface plate 21a on which the workpiece 10 is placed, and an upper surface plate 21b that presses the workpiece 10 from above and applies pressure to wrap the workpiece 10.
Note that lapping in this embodiment can be performed using an abrasive. Although it does not specifically limit as an abrasive, For example, the abrasives which consist of an alumina or a diamond can be used by slurrying. Moreover, you may provide the grindstone in which these abrasives were disperse | distributed and included in the upper surface plate 21b and the lower surface plate 21a.

(Inner and outer grinding process)
FIG. 1-1 (b) shows the inner and outer peripheral grinding steps. In this step, grinding that is roughing of the inner peripheral surface of the opening 12 of the workpiece 10 and the outer peripheral surface of the outer periphery 13 of the workpiece 10 is performed. In the present embodiment, the inner peripheral surface and the outer peripheral surface are simultaneously ground. Specifically, the opening 12 provided in the center of the workpiece 10 is ground by the inner peripheral grindstone 22, and the outer periphery 13 of the workpiece 10 is ground by the outer peripheral grindstone 23. At this time, the workpiece 10 is sandwiched between the inner peripheral grindstone 22 and the outer peripheral grindstone 23 and simultaneously processed. Thereby, it becomes easy to ensure the concentricity of the inner diameter and the outer diameter of the workpiece 10.

  Moreover, in this Embodiment, the surface shape of the inner periphery grindstone 22 and the outer periphery grindstone 23 is a waveform. In other words, the inner peripheral grindstone 22 and the outer peripheral grindstone 23 have convex portions that become peaks and concave portions that become valleys on the surfaces thereof. Here, a plurality of convex portions and concave portions are provided, and are alternately provided along the axial direction of the inner peripheral grindstone 22 and the outer peripheral grindstone 23. For this reason, in this embodiment, not only the inner peripheral surface of the opening 12 and the outer peripheral surface of the outer periphery 13 of the workpiece 10 can be ground, but also the chamfering of the edges in the opening 12 and the outer periphery 13 can be performed together. It becomes possible.

(Inner grinding process)
FIG. 1-1 (c) shows the inner periphery polishing step. In this step, polishing is performed to further smooth the inner peripheral surface of the workpiece 10 that has been ground in the inner and outer peripheral grinding step shown in FIG.
Specifically, the workpieces 10 are first stacked and set on a holder (not shown). And the brush 24 is inserted in the opening 12 of the workpiece | work 10 set to this holder. Then, the brush 24 is rotated at a high speed while pouring the polishing liquid into the opening 12 of the workpiece 10. Thereby, the inner peripheral surface of the workpiece 10 is polished by the brush 24. In this embodiment, since the brush 24 is used in this way, the inner peripheral surface of the workpiece 10 can be polished, and the chamfered portion in the inner and outer peripheral grinding step can also be polished. As the polishing liquid, for example, a slurry obtained by dispersing cerium oxide abrasive grains in water can be used.

  Here, FIG. 2 is a diagram showing an example of the brush 24 used in the inner periphery polishing step. The brush 24 includes a brush portion 61 in which hair ends are arranged in a spiral shape, and a shaft 62 that is formed continuously at both ends of the brush portion 61 and forms one end and the other end. For example, when polishing the inner peripheral surface of a small-diameter disk such as 0.85 inch, it is necessary to make the core of the brush 24 thinner. Therefore, in the present embodiment, for example, between a plurality of wires (material: for example, a mild steel wire (SWRM), a hard steel wire (SWRH), a stainless wire (SUSW), a brass wire (BSW), etc.) The brush portion 61 is formed by sandwiching hair (material: nylon (trade name of DuPont, for example)) and twisting the wire in which the hair is sandwiched. Here, by twisting the wire to form the brush part 61, the brush tip of the brush formed on the brush part 61 can be spiral. In addition, by making the brush tip formed in the brush portion 61 spiral, the polishing liquid can flow in the axial direction through the opening 12 of the workpiece 10 to be inserted. As a result, the polishing liquid can be transported satisfactorily.

(Secondary lap process)
FIG. 1-1 (d) shows the secondary lapping process. In this step, the lapping is again performed on the surface 11 of the workpiece 10 that has been lapped in the primary lapping step shown in FIG. More specifically, a wrapping machine 40 having a lower surface plate 21a on which the workpiece 10 is placed and an upper surface plate 21b that presses the workpiece 10 from above and applies pressure to wrap the workpiece 10 is provided. Then, lapping is performed again on the surface 11 of the workpiece 10.

(Outer periphery polishing process)
FIG. 1-2 (e) shows the outer periphery polishing step. In this step, polishing is performed to further smooth the outer peripheral surface of the workpiece 10 ground in the inner and outer peripheral grinding step shown in FIG. 1-1 (b).
Specifically, first, the workpiece 10 is stacked on the opening 12 portion of the workpiece 10 through the jig 25, and the workpiece 10 is set on the jig 25. Then, the brush 26 is brought into contact with the stacked workpieces 10 while being poured into the outer peripheral portion 13 of the workpiece 10 and rotated at a high speed. Thereby, the outer peripheral surface of the workpiece | work 10 can be grind | polished.
At this time, since the brush 26 is used for polishing, the outer peripheral surface of the workpiece 10 can be polished, and the chamfered portion in the inner and outer peripheral grinding step can also be polished. As the polishing liquid, as in the case of the inner peripheral polishing step, for example, a slurry obtained by dispersing cerium oxide abrasive grains in water can be used.

(Primary polishing process)
FIG. 1-2 (f) shows the primary polishing process. In this step, the surface 11 of the workpiece 10 lapped in the secondary lapping step shown in FIG. 1-1 (d) is further polished by polishing using a polishing machine 60 to increase the smoothness. . The polishing machine 60 has substantially the same configuration as the lapping machine 40 described above, but the materials used for polishing are partially different as shown below.
In this primary polishing step, for example, a hard polishing cloth formed of urethane is used. In this primary polishing step, cerium oxide abrasive grains dispersed in water and slurried can be used as an abrasive.

(Secondary polishing process)
FIG. 1-2 (g) shows the secondary polishing step. In this step, the surface 11 of the workpiece 10 polished in the primary polishing step shown in FIG. 1-2 (f) is further polished by precision polishing using a polishing machine 60, and the surface 11 is finally polished. Finish.
In this secondary polishing step, for example, a suede-like soft polishing cloth is used. In the secondary polishing step, cerium oxide abrasive grains or colloidal silica dispersed in a solvent such as water and slurried can be used as an abrasive.

(Final cleaning / inspection process)
FIG. 1-2 (h) shows the final cleaning / inspection process. In the final cleaning, the abrasive used in the series of steps described above is removed. For the cleaning, a method such as chemical cleaning with a detergent (chemical) using ultrasonic waves can be used.
In the inspection process, for example, the surface of the workpiece 10 is inspected for scratches or distortions by an optical inspection device using a laser.

Here, the secondary polishing step shown in FIG. 1-2 (g) will be described in more detail. In the secondary polishing step, the surface 11 of the workpiece 10 is polished using the polishing machine 60 as described above.
Here, FIG. 3 is a diagram showing the structure of the polishing machine 60.
As shown in the figure, a polishing machine 60 includes a lower surface plate (grinding surface plate, lower polishing surface plate) 21a on which the workpiece 10 is placed, and an upper surface plate that presses the workpiece 10 from above and applies pressure to the workpiece 10. (Grinding surface plate) 21b.

Here, the tooth part 42 is provided in the outer peripheral part of the lower surface plate 21a. A sun gear 44 is provided at the center of the lower surface plate 21a. Further, a disk-shaped carrier 30 for positioning the workpiece 10 when lapping is performed is placed on the lower surface plate 21a.
Five carriers 30 are installed in the polishing machine 60 shown in FIG. A tooth portion 32 is provided on the outer peripheral portion of the carrier 30, and the carrier 30 meshes with both the tooth portion 42 of the lower surface plate 21 a and the sun gear 44 via the tooth portion 32. Further, rotation shafts 46a and 46b for rotating the lower surface plate 21a and the upper surface plate 21b are provided at the center portions of the lower surface plate 21a and the upper surface plate 21b, respectively.

In the secondary polishing step, the carrier 30 is first placed on the lower surface plate 21a of the polishing machine 60. Next, the workpiece 10 is placed.
FIG. 4 is an enlarged view of the carrier 30. As shown above, the carrier 30 shown in FIG. The carrier 30 is provided with a plurality of circular holes (openings) 34 on which the workpiece 10 is placed (set) when lapping. The diameter of the hole 34 is slightly larger than the diameter of the workpiece 10. By setting it as such a form, when lapping is performed, it can suppress that extra stress is applied to a part of outer periphery end of the workpiece | work 10. FIG.

Here, in the present embodiment, the diameter of the hole 34 is, for example, about 1 mm larger than the diameter of the workpiece 10. Further, the holes 34 are arranged at almost equal intervals, and in the case of the present embodiment, 35 holes 34 are provided. More specifically, the carrier 30 is provided with five hole portions 34 provided along the circumferential direction and arranged at equal intervals at a location closest to the center of the carrier 30. In addition, twelve hole portions 34 are provided on the outer peripheral side of the five hole portions 34 and are also provided along the circumferential direction and arranged at equal intervals. Further, 18 hole portions 34 provided along the circumferential direction and arranged at equal intervals are provided on the outer peripheral side of the twelve hole portions 34 (the outermost peripheral side of the carrier 30).
Although it does not specifically limit as a material of the carrier 30, For example, the epoxy resin reinforced by mixing an aramid fiber and glass fiber can be used.

Here, after setting the workpiece 10 inside the hole 34 in the carrier 30, the upper surface plate 21 b is moved until it contacts the workpiece 10, and the polishing machine 60 is operated.
The operation of the polishing machine 60 at this time will be described with reference to FIG. When the polishing machine 60 is operated, the upper rotating shaft 46b in the drawing is rotated in one direction, and the upper surface plate 21b is rotated in the same one direction. Further, the lower rotating shaft 46a in the figure is rotated in the opposite direction to the rotation of the rotating shaft 46b, and the lower surface plate 21a is rotated in the same direction as the rotating shaft 46a. Thereby, the tooth part 42 of the lower surface plate 21a also rotates in the same direction as the rotating shaft 46a. The sun gear 44 at the center also rotates in the same direction as the rotation shaft 46a.

  Thus, by rotating the upper surface plate 21b, the lower surface plate 21a, and the sun gear 44, the carrier 30 meshing with these gears performs a so-called planetary motion in which a rotation motion and a revolution motion are combined. Similarly, the workpiece 10 placed inside the hole 34 in the carrier 30 also performs planetary motion. By using such a polishing machine 60, the workpiece 10 can be polished more accurately and quickly.

By the way, when the workpiece 10 is set in the hole 34 of the carrier 30 during the secondary polishing, the outer peripheral portion of the workpiece 10 may come into contact with the surface of the carrier 30 and the surface of the carrier 30 or the workpiece 10 may be damaged. is there.
Here, FIG. 5 (state diagram when setting the workpiece 10) will be described in detail. As shown in FIG. 5A, when the workpiece 10 is set in the hole 34 of the carrier 30, the workpiece 10 The outer peripheral portion may come into contact with the surface of the carrier 30, and the surface of the carrier 30 or the outer peripheral portion of the workpiece 10 may be damaged. Also, as shown in FIG. 5B, when the workpiece 10 is slid along the surface of the carrier 30 and set, the surface of the carrier 30 and the surface of the workpiece 10 may be damaged.
For this reason, in the secondary polishing step in the present embodiment, a sheet-like carrier adapter (an example of a covering member) that covers the surface of the carrier 30 is placed on the carrier 30 before starting the setting of the workpiece 10. It is said.

FIG. 6 is a diagram illustrating the carrier adapter.
The carrier adapter 50 shown in the figure is substantially the same shape as the carrier 30 and is formed in a disc shape. The carrier adapter 50 also includes a plurality of holes (openings) 54. Here, the plurality of hole portions 54 have the same arrangement relationship as the arrangement relationship of the hole portions 34 (see FIG. 4) provided in the carrier 30. That is, the carrier adapter 50 is provided with a hole 54 corresponding to the hole 34 of the carrier 30.

  More specifically, the carrier adapter 50 has 35 holes 54. More specifically, the carrier adapter 50 is provided with five hole portions 54 provided along the circumferential direction and arranged at equal intervals at a location closest to the center of the carrier adapter 50. Further, twelve hole portions 54 are also provided on the outer peripheral side of the five hole portions 54 and are provided along the circumferential direction and arranged at equal intervals. Furthermore, 18 holes 54 provided along the circumferential direction and arranged at equal intervals are provided on the outer peripheral side of the twelve holes 54 (the outermost peripheral side of the carrier adapter 50).

  Further, the carrier adapter 50 in the present embodiment is more flexible and softer than the carrier 30. Here, for the carrier adapter 50, for example, the same material as the suede-like soft polishing cloth used in the secondary polishing step can be used. Moreover, you may form with a rubber material, for example. Further, the thickness of the carrier adapter 50 is not particularly limited, but preferably has a thickness that can be recessed when the workpiece 10 is abutted against the carrier adapter 50. In this embodiment, the thickness is about 2 mm.

Further, a second hole 58 for facilitating positioning of the carrier adapter 50 with respect to the carrier 30 is provided in the vicinity of the outer periphery of the carrier adapter 50. The second hole 58 is provided so as to penetrate the carrier adapter 50 and has a triangular shape.
On the other hand, although not described above, as shown in FIG. 4, a triangular mark 38 having a color different from that of the main body portion of the carrier 30 is attached to the surface of the carrier 30 and in the vicinity of the outer peripheral portion. The mark 38 is slightly smaller than the second hole 58 in the carrier adapter 50.

  Here, when the carrier adapter 50 is attached to the carrier 30, if the carrier 30 and the carrier adapter 50 are out of phase, the hole 34 of the carrier 30 and the hole 54 of the carrier adapter 50 may not match. It can happen. In the present embodiment, when the carrier adapter 50 is mounted on the carrier 30, the carrier 34 and the carrier adapter 50 are positioned so that the mark 38 can be seen through the second hole 58. The hole portion 54 of the adapter 50 is matched.

In other words, if the carrier 30 and the carrier adapter 50 are positioned so that the mark 38 can be seen through the second hole 58, the hole 34 of the carrier 30 and the hole 54 of the carrier adapter 50 overlap each other. . By providing the second hole 58 and the mark 38 in this manner, the hole 34 of the carrier 30 and the hole 54 of the carrier adapter 50 can be promptly matched.
In the present embodiment, the second hole 58 is provided on the outer peripheral side of the carrier adapter 50, and the mark 38 is also provided on the outer peripheral side of the carrier 30. Thus, when the 2nd hole 58 and the mark 38 are provided in the outer peripheral part side, the positioning of the carrier 30 and the carrier adapter 50 can be performed more simply compared with the case where it provides in the center part side. In addition, the 2nd hole 58 and the mark 38 can be grasped | ascertained as a parameter | index part used as the parameter | index at the time of positioning with the carrier 30 and the carrier adapter 50. FIG.

  The carrier adapter 50 has a through hole 59a and a ring portion 59b (an example of a ring-shaped member) that is formed by a string being tied at both ends and is passed through the through hole 59a. The ring portion 59b has a diameter that allows the finger of an operator (user) who removes the carrier adapter 50 to pass through. In other words, it has a diameter into which an operator's finger can be inserted. When the carrier adapter 50 is removed from the carrier 30 (described later), the operator's finger is hung on the ring portion 59b. When the ring portion 59b is provided in this way, the carrier adapter 50 can be removed more easily than when the ring portion 59b is not provided.

  Here, FIG. 7 shows a state after the carrier adapter 50 is attached to the carrier 30. If the carrier 30 and the carrier adapter 50 are positioned so that the mark 38 can be seen through the second hole 58 as described above and as shown in FIG. 7A, the hole 34 of the carrier 30 and the hole 54 of the carrier adapter 50 are provided. Matches.

  Here, FIG. 7B shows a cross section taken along line AA of FIG. As shown in the figure, it can be seen that the surface of the carrier 30 is covered with the carrier adapter 50 by attaching the carrier adapter 50 to the carrier 30. In this embodiment, the workpiece 10 is set in the hole 34 of the carrier 30 through (through) the hole 54 of the carrier adapter 50 in the state shown in this figure. Then, after the setting of the workpiece 10 is completed, the carrier adapter 50 is removed by pulling up the ring portion 59b. Thereafter, as described above, the upper surface plate 21b is moved until it contacts the workpiece 10, and the polishing machine 60 is operated.

In the primary wrapping process and the secondary wrapping process, a wrapping machine 40 having the same configuration as the polishing machine 60 is used. In the primary polishing process, a polishing machine 60 is used. When using the lapping machine 40 and the polishing machine 60, the carrier adapter 50 can be attached to the carrier 30 in the same manner as described above. That is, the carrier adapter 50 can be used not only in the secondary polishing process but also in the primary wrapping process, the secondary wrapping process, and the primary polishing process.
Further, in this embodiment, the carrier 30 is covered by one carrier adapter 50 provided with a plurality of holes 54. For example, a plurality of sheet-like members are placed so as not to overlap the holes 34. Thus, the carrier 30 may be coated.

It is the figure which showed the manufacturing process of the disk shaped board | substrate (disk board | substrate). It is the figure which showed the manufacturing process of the disk shaped board | substrate (disk board | substrate). It is the figure which showed an example of the brush used in an inner periphery grinding | polishing process. It is the figure which showed the structure of the polishing machine. It is the figure which expanded and showed the carrier. It is a state figure at the time of setting a workpiece | work. It is a figure explaining a carrier adapter. It is the figure which showed the state after mounting | wearing a carrier adapter with a carrier.

DESCRIPTION OF SYMBOLS 10 ... Work, 21a ... Lower surface plate, 21b ... Upper surface plate, 30 ... Carrier, 34 ... Hole part, 38 ... Mark, 50 ... Carrier adapter, 54 ... Hole part, 58 ... Second hole part, 59b ... Ring part

Claims (5)

A carrier is placed on the lower polishing surface plate of a pair of upper and lower grinding surface plates, a disk-shaped substrate is set in the opening of the carrier, and the front and back surfaces of the disk-shaped substrate are ground by the pair of grinding surface plates. A method for manufacturing a disc-shaped substrate,
An opening is formed corresponding to the opening of the carrier, and the opening of the carrier adapter and the opening of the carrier are overlapped with a carrier adapter that is more flexible than the carrier and can be attached to and detached from the carrier. The disk-shaped substrate is set in the opening of the carrier through the opening of the carrier adapter after the surface of the carrier is covered with the carrier adapter in a state of being positioned as described above. A method for manufacturing a disc-shaped substrate. Said carrier adapter and the carrier, the manufacturing method of the disk-shaped substrate according to claim 1, characterized in that it has an index portion indicative of the time of the positioning. The indicator portion of the carrier is provided on the outer peripheral side of the carrier formed in a disc shape,
3. The method for manufacturing a disk-shaped substrate according to claim 2 , wherein the index portion of the carrier adapter is provided on an outer peripheral side of the carrier adapter formed in a disk shape. The said carrier adapter, the production of disk-shaped substrate according to claim 1, wherein the fingers of the user can be inserted a ring-shaped member when the carrier adapter is removed from the carrier is attached by the user Method. A disk-shaped substrate mounted on a pair of upper and lower grinding surface plates, a disk-shaped substrate is set in the opening of the carrier, and the front and back surfaces of the disk-shaped substrate are ground by the pair of grinding surface plates. A manufacturing method comprising:
After covering the surface of the carrier with a carrier adapter that can be attached to and detached from the carrier, the step of setting the disk-shaped substrate in the opening of the carrier, and before the lapping step or the polishing step, A method for manufacturing a disk-shaped substrate, comprising a step of removing a carrier adapter from the carrier.

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