Device for manufacturing disk-shaped substrate, and method for manufacturing disk-shaped substrate

Abstract

This device for manufacturing a disk-shaped substrate comprises: a lower surface plate on which a disk-shaped substrate is placed; an upper surface plate that rotates while the disk-shaped substrate is sandwiched between the lower surface plate and the upper surface plate and polishes or grinds the disk-shaped substrate; a shaft part that is provided above the upper surface plate and extends in a vertical direction; a flange that protrudes in the radial direction at a lower section of the shaft part and in which a plurality of through-holes penetrating in the vertical direction are arranged in the radial direction; and a fastening member that fastens the flange to the upper surface plate through the through-holes and can be replaced with the plurality of through-holes.

Description

Disk-shaped substrate manufacturing apparatus and disk-shaped substrate manufacturing method

[0001] The present disclosure relates to a disk-shaped substrate manufacturing apparatus and a disk-shaped substrate manufacturing method.

[0002] Known disk-shaped substrate manufacturing apparatuses include a lower surface plate and an upper surface plate, as disclosed in Japanese Patent Application Laid-Open Nos. 2004-216492 and 2006-150507. In the manufacturing apparatuses disclosed in Japanese Patent Application Laid-Open Nos. 2004-216492 and 2006-150507, a vertically extending shaft is provided above the upper surface plate. A flange extending radially is provided at the lower end of this shaft. A plurality of pulleys are attached to each of the flange and the upper surface plate. A single wire is stretched across the plurality of pulleys. The shape of the upper surface plate is corrected by adjusting the tension of the wire.

[0003] In the manufacturing apparatuses disclosed in JP 2004-216492 A and JP 2006-150507 A, the upper surface plate is suspended from the flange by wires, supports, or the like, so the weight of the upper surface plate can cause deformation of the flange itself. If the flange is deformed, the shape of the upper surface plate cannot be corrected with high precision. As a result, a discrepancy occurs in the flatness between the lower surface of the upper surface plate and the upper surface of the lower surface plate, reducing the processing precision of the disk-shaped substrate.

[0004] Therefore, an object of the present disclosure is to provide a disk-shaped substrate manufacturing apparatus and a disk-shaped substrate manufacturing method that can suppress a decrease in the processing accuracy of the disk-shaped substrate.

[0005] The present disclosure includes the following aspects. <1> A disk-shaped substrate manufacturing device comprising: a lower surface plate on which a disk-shaped substrate is placed; an upper surface plate that rotates with the disk-shaped substrate sandwiched between the lower surface plate and the upper surface plate and polishes or grinds the disk-shaped substrate; a shaft portion provided above the upper surface plate and extending in the vertical direction; a flange that protrudes radially from a lower portion of the shaft portion, the flange having a plurality of through holes that penetrate in the vertical direction and are arranged in the radial direction; and fastening members that fasten the flange to the upper surface plate through the through holes and are replaceable in the plurality of through holes. <2> The disk-shaped substrate manufacturing device described in <1>, wherein the plurality of through holes have fastening positions where the fastening members are fastened and non-fastening positions where the fastening members are not fastened, and the fastening members fastened at the fastening positions can be replaced in the non-fastening positions. <3> The disk-shaped substrate manufacturing device described in <1> or <2>, wherein the plurality of through holes are arranged in a circumferential direction of the flange. <4> A method for manufacturing a disk-shaped substrate, comprising: a first step of rotating an upper surface plate with a disk-shaped substrate sandwiched between it and a lower surface plate and polishing or grinding the disk-shaped substrate; and a second step of changing a fastening position of a fastening member depending on the flatness of the lower surface of the upper surface plate, wherein the fastening member fastens a flange to the upper surface plate through a through hole, the flange is a flange that protrudes radially from a lower part of a shaft portion, and a plurality of the through holes that penetrate in the vertical direction are arranged in the radial direction, and the shaft portion is provided above the upper surface plate and extends in the vertical direction. <5> The plurality of through holes have fastening positions where the fastening members are fastened and non-fastening positions where the fastening members are not fastened, and the method for manufacturing a disk-shaped substrate described in <4>, wherein the fastening positions of the fastening members are changed by relocating the fastening members fastened at the fastening positions to the non-fastening positions in the second step.

[0006] According to the present disclosure, there are provided a disk-shaped substrate manufacturing apparatus and a disk-shaped substrate manufacturing method that can suppress a decrease in the processing accuracy of the disk-shaped substrate.

[0007] Fig. 1 is a perspective view showing a manufacturing apparatus according to an embodiment of the present disclosure; Fig. 2 is a side cross-sectional view showing a manufacturing apparatus according to an embodiment of the present disclosure; Fig. 3 is a plan view showing an upper surface plate and a flange according to an embodiment of the present disclosure; Fig. 4 is a flow chart of a manufacturing method according to an embodiment of the present disclosure.

[0008] Embodiments of the present disclosure will be described below. However, the present disclosure is not limited to the following embodiments. In the following embodiments, components are not essential unless otherwise specified. When embodiments are described with reference to drawings in the present disclosure, the configuration of the embodiment is not limited to the configuration shown in the drawings. Furthermore, the sizes of the components in each drawing are conceptual. Therefore, the front-to-back, left-to-right, and top-to-bottom dimensional ratios of each component, and the front-to-back, left-to-right, and top-to-bottom dimensional ratios between each component, are not limited to the illustrated dimensional ratios. Furthermore, the front-to-back, left-to-right, and top-to-bottom dimensional ratios of each component may differ from the actual dimensional ratios. Furthermore, unless otherwise specified in the present disclosure, the number of each component of the present disclosure is not limited to one, and multiple components may be present. Note that in the following description of the drawings, similar parts are designated by similar symbols.

[0009] <Manufacturing Apparatus 10> A manufacturing apparatus 10 according to this embodiment will be described with reference to the drawings. Note that the manufacturing apparatus for disk-shaped substrates according to the present disclosure is not limited to the manufacturing apparatus 10. As an example, the manufacturing apparatus 10 is an apparatus that polishes a disk-shaped substrate 100 to manufacture a disk-shaped substrate 200. The disk-shaped substrate 200 is a processed disk-shaped substrate obtained by performing a polishing process on the disk-shaped substrate 100.

[0010] 1 and 2, the manufacturing apparatus 10 includes a lower surface plate 12, an upper surface plate 20, a shaft portion 28, a flange 29, a fastening member 34, a sun gear 40, an internal gear 42, and a carrier 44. Below, the disk-shaped substrate 100, each portion of the manufacturing apparatus 10, modified examples of the manufacturing apparatus 10, a manufacturing method for the disk-shaped substrate 200, and modified examples of the manufacturing method will be described.

[0011] <Disc-shaped substrate 100> The disc-shaped substrate 100 is a substrate formed in a disc shape. Specifically, the disc-shaped substrate 100 is formed in an annular shape having holes in a plan view. Note that the plan view here refers to the case where the disc-shaped substrate 100 is viewed from one side in the thickness direction of the disc-shaped substrate 100. The disc-shaped substrate 100 is a substrate before a polishing process is performed.

[0012] The disk-shaped substrate 100 may be, for example, a substrate for a magnetic recording medium. Furthermore, the disk-shaped substrate 100 may be a substrate made of a metal material such as aluminum or an aluminum alloy substrate, or glass. Hereinafter, aluminum substrates, aluminum alloy substrates, glass substrates, etc. will also be collectively referred to as "substrates." Hereinafter, aluminum substrates and aluminum alloy substrates will also be collectively referred to as "aluminum substrates." A plating layer may be formed on the surface of the aluminum substrate. Note that the use, material, type, shape, etc. of the disk-shaped substrate 100 are not limited to those described above, and various disk-shaped substrates may be used as the disk-shaped substrate 100.

[0013] <Lower surface plate 12> As shown in Figures 1 and 2, the lower surface plate 12 is a disk-shaped member. The lower surface plate 12 has a circular, horizontal upper surface. A polishing cloth 14 is disposed on the upper surface of the lower surface plate 12. A disk-shaped substrate 100 is placed on this polishing cloth 14. The lower surface plate 12 is supported by a support unit (not shown) so as to be rotatable about a vertical axis VA. The lower surface plate 12 rotates by receiving a rotational force from a drive unit 16.

[0014] <Upper surface plate 20, shaft portion 28, flange 29, and fastening member 34> As shown in Figures 1 and 2, the upper surface plate 20 is a disk-shaped member. The upper surface plate 20 has a horizontal, annular lower surface. A polishing cloth 24 is disposed on the lower surface of the upper surface plate 20. The polishing cloth 24 disposed on the upper surface plate 20 is positioned opposite the polishing cloth 14 disposed on the lower surface plate 12. The shaft portion 28 is disposed above the upper surface plate 20 and extends vertically along the vertical axis VA. The flange 29 protrudes radially from the lower portion of the shaft portion 28. The flange 29 is formed in a disk shape. The outer diameter of the flange 29 is, for example, 50% or more but less than 100% of the outer diameter of the upper surface plate 20. The flange 29 and the shaft portion 28 are connected by a connecting portion 27. The connecting portion 27 is, for example, configured as a universal joint that allows the angle of the flange 29 to be changed relative to the shaft portion 28.

[0015] The flange 29 is formed with a plurality of through holes 32 penetrating in the up-down direction. The plurality of through holes 32 are arranged in the radial direction of the flange 29, as shown in FIGS. 1, 2, and 3. Hereinafter, the plurality of through holes 32 arranged in the radial direction of the flange 29 will be referred to as a hole group 33. In this embodiment, the hole group 33 is composed of three through holes 32 arranged in a row in the radial direction of the flange 29. A plurality of hole groups 33 are arranged in the circumferential direction of the flange 29. In this embodiment, four sets of hole groups 33 are arranged at equal angular intervals in the circumferential direction of the flange 29. In other words, the hole groups 33 are arranged at 90-degree intervals in the circumferential direction of the flange 29.

[0016] The fastening members 34 fasten the flange 29 to the upper surface plate 20 through the through holes 32. In this embodiment, the fastening members 34 inserted into the through holes 32 fasten the upper surface plate 20 and the flange 29 together while the lower surface of the flange 29 is in contact with the upper surface of the upper surface plate 20. In this manner, the positions of the through holes 32 are the fastening positions using the fastening members 34. Nuts 35 having internal threads are provided at positions on the upper surface plate 20 corresponding to the through holes 32. The fastening members 34 are screwed onto the nuts 35. The fastening members 34 are replaceable with each of the through holes 32 in the hole group 33. In the example shown in FIGS. 1 and 2 , the fastening members 34 fasten the flange 29 to the upper surface plate 20 at the innermost through hole 32 in the hole group 33. The fastening members 34 can also be replaced with the outermost through holes 32. In this manner, in this embodiment, the fastening members 34 are fastened to some of the multiple through holes 32. In other words, the plurality of through holes 32 have fastening portions where the fastening members 34 are fastened and non-fastening portions where the fastening members 34 are not fastened. The fastening members 34 fastened at the fastening portions can be relocated to the non-fastening portions.

[0017] The upper surface plate 20 is supported by the support unit 22 via a flange 29 and a shaft unit 28 so as to be rotatable about a vertical axis VA. The upper surface plate 20 rotates by receiving a rotational force from the drive unit 26. In this embodiment, the upper surface plate 20 rotates with the disk-shaped substrate 100 sandwiched between it and the lower surface plate 12, and polishes the disk-shaped substrate 100. The support unit 22 is supported by the lifting unit 23 so that the upper surface plate 20 can be raised and lowered along the vertical axis VA. The support unit 22 and the upper surface plate 20 are raised and lowered by driving the lifting unit 23. The upper surface plate 20 moves towards and away from the lower surface plate 12 as it is raised and lowered.

[0018] 1 and 2, the sun gear 40 is provided at the center of the lower surface plate 12. The sun gear 40 rotates about a vertical axis VA by being driven by a drive unit 41. The sun gear 40 may be a spur gear, a pin gear, or the like, having a row of teeth integrally formed on its side surface.

[0019] The internal gear 42 is arranged concentrically with the sun gear 40. The internal gear 42 has an annular cylindrical body 49. Internal teeth are formed on the inner peripheral surface of the cylindrical body 49. The internal gear 42 of this embodiment is held non-rotatably by a holding member (not shown). Alternatively, a drive unit that rotates the internal gear 42 may be provided, and the internal gear 42 may be rotated around the vertical axis VA. When the internal gear 42 is rotated, the sun gear 40 may be held non-rotatably. Furthermore, the internal gear 42 may be a pin gear or the like in addition to a spur gear.

[0020] The carrier 44 is a thin, disk-shaped member. External teeth are formed on the outer circumferential surface of the carrier 44. As shown in Fig. 1, the carrier 44 has a plurality of holding holes 46 formed therein. The holding holes 46 hold the disk-shaped substrates 100.

[0021] A plurality of carriers 44 are arranged on the lower surface plate 12. The carriers 44 mesh with the sun gear 40 and the internal gear 42, and rotate around the sun gear 40 while revolving around the sun gear 40 in response to the rotation of at least one of the sun gear 40 and the internal gear 42.

[0022] In this embodiment, the upper surface plate 20 contacts the upper surface of the disk-shaped substrate 100 held by the carrier 44, and the lower surface plate 12 contacts the lower surface of the disk-shaped substrate 100. By revolving and rotating the carrier 44 in this state, both the upper and lower surfaces of the disk-shaped substrate 100 are polished by the polishing cloths 14, 24.

[0023] <Modifications of the manufacturing apparatus 10> In the above-described embodiment, the hole group 33 is configured with three through holes 32, but the number of through holes 32 in the hole group 33 is not limited to three and may be any number. In the above-described embodiment, the hole groups 33 are arranged at 90-degree intervals in the circumferential direction of the flange 29, but this is not limited thereto. The hole groups 33 may be arranged at intervals of, for example, 30 degrees, 45 degrees, 60 degrees, 180 degrees, etc. Furthermore, the hole groups 33 may not be arranged at equal angular intervals.

[0024] The manufacturing apparatus 10 in the above-described embodiment is an apparatus that polishes the disk-shaped substrate 100, but is not limited to this. The manufacturing apparatus 10 may also be an apparatus that grinds the disk-shaped substrate 100. The manufacturing apparatus 10 in the above-described embodiment may further include one or more other devices. Examples of such other devices include a storage rack that stores the disk-shaped substrate 100 before processing or the disk-shaped substrate 200 after processing, a cleaning device that cleans the disk-shaped substrate 200, a drying device that dries the disk-shaped substrate 200, and the like.

[0025] <Method for manufacturing disk-shaped substrate 200> An example of a method for manufacturing a disk-shaped substrate according to the present disclosure will be described below with reference to the drawings. Note that the method for manufacturing a disk-shaped substrate according to the present disclosure is not limited to the following example. The manufacturing method of this embodiment is a method for manufacturing a disk-shaped substrate 200. The manufacturing method of this embodiment is performed using a manufacturing apparatus 10, as an example.

[0026] For example, if the disk-shaped substrate 100 is an aluminum substrate, the manufacturing method for the disk-shaped substrate 200 includes the following steps, as shown in FIG. 4 : Blank substrate preparation step: An aluminum substrate of the desired dimensions is prepared. The aluminum substrate of the desired dimensions can be obtained, for example, by rolling an aluminum alloy ingot to obtain an aluminum alloy plate material of approximately 2 mm or less in thickness, and then punching the obtained aluminum alloy plate material into a disk shape. Cutting step: The prepared aluminum substrate is subjected to chamfering of the inner and outer diameters and cutting of both main surfaces. Grinding step: Both main surfaces of the cut aluminum substrate are subjected to grinding using a grinding wheel. The grinding step can reduce, for example, the surface roughness and waviness of the cut aluminum substrate. Plating step: The ground aluminum substrate is plated with NiP or the like. Plating can, for example, harden the surface or suppress surface defects. Polishing step: Both main surfaces of the aluminum substrate on which the plating film has been formed are polished. In the polishing step, the upper surface plate 20 rotates with the disk-shaped substrate 100 sandwiched between it and the lower surface plate 12, and the surface of the disk-shaped substrate 100 is polished.

[0027] When the disk-shaped substrate 100 is a glass substrate, the manufacturing method of the disk-shaped substrate 200 includes, for example, the following steps. Note that when the disk-shaped substrate 100 is a glass substrate, the manufacturing method differs from when the disk-shaped substrate 100 is an aluminum substrate in that it does not include a cutting step. Manufacturing apparatus preparation step: A manufacturing apparatus 10 is prepared. Blank substrate preparation step: A glass blank substrate of the desired size is prepared. The glass blank substrate of the desired size is, for example, produced by press molding or the like from a glass blank that serves as the material for a plate-shaped glass substrate for a magnetic recording medium having a pair of main surfaces, and a circular hole is formed in the center of the produced glass blank to form an annular shape. Next, shaping is performed to obtain a glass substrate having a chamfered surface. The inner and outer peripheral end surfaces of the shaped glass substrate are ground and polished. Grinding step: The main surfaces of the glass substrate after the edge polishing are ground using a fixed abrasive. Polishing step: The main surfaces of the glass substrate after the grinding step are polished using a predetermined abrasive. During the polishing process, the glass substrate may be subjected to a chemical strengthening treatment. In the polishing process, the upper surface plate 20 rotates with the disk-shaped substrate 100 sandwiched between the upper surface plate 20 and the lower surface plate 12, and the surface of the disk-shaped substrate 100 is polished.

[0028] Furthermore, the manufacturing method of this embodiment includes a measuring step and a changing step, as shown in FIG. 4 . The measuring step and the changing step are performed, for example, after the polishing step is performed. The measuring step and the changing step may be performed each time the polishing step is performed, or may be performed after the polishing step is performed multiple times. The measuring step and the changing step can be performed at any time after the manufacturing apparatus 10 is prepared, as long as the upper surface plate 20 and the lower surface plate 12 are not in use. The manufacturing apparatus preparation step described above is an example of a first step. The polishing step described above is an example of a second step. The measuring step is an example of a third step. The changing step is an example of a fourth step.

[0029] <Measurement Step> In the measurement step, the flatness of the lower surface of the upper surface plate 20 is measured. The flatness of the upper surface plate 20 is measured, for example, by a measurement sensor attached to the upper surface plate 20. As the measurement sensor, a strain sensor, a displacement sensor, or the like can be used.

[0030] <Modification Process> In the modification process, the fastening positions of the fastening members 34 are changed according to the flatness of the upper surface plate 20 measured in the measurement process. The modification of the fastening positions of the fastening members 34 is performed, for example, by relocating the fastening members 34, which are fastened at the fastening positions of the multiple through holes 32, to non-fastening positions. For example, if downward deflection occurs on the outer periphery of the upper surface plate 20, the fastening positions can be changed to the outer periphery by relocating the fastening members 34 to the outer periphery-side through holes 32 in the hole groups 33. The fastening positions do not have to be consistent in the circumferential direction of the flange 29 in each hole group 33. That is, each hole group 33 may be fastened at different positions in the circumferential direction of the flange 29. Furthermore, each hole group 33 may be fastened at multiple fastening positions. Furthermore, if the flatness measured in the measurement process is within the allowable range, the modification process is optional. That is, in the manufacturing method of this embodiment, the modification process may be performed if the flatness exceeds the allowable range.

[0031] In the changing step, the fastening positions of the fastening members 34 are changed in accordance with the flatness of the upper surface plate 20 measured in the measuring step, but this is not limited to this. For example, in the changing step, the fastening positions may be changed periodically regardless of the flatness measurement results. Furthermore, the fastening positions may be changed based on the quality (edge ​​sagging, flatness, minute waviness, etc.) of the processed disk-shaped substrate 200, assuming that the flatness of the upper surface plate 20 has deteriorated. In this way, when the fastening positions are changed regardless of the flatness measurement results, the measurement step may be omitted. In other words, the measurement step is optional in the manufacturing method disclosed herein.

[0032] As described above, in this embodiment, the fastening members 34 are replaceable with the multiple through holes 32, so the fastening positions of the fastening members 34 can be changed depending on the flatness of the upper surface plate 20. As a result, it is possible to eliminate any discrepancy in flatness between the lower surface of the upper surface plate 20 and the upper surface of the lower surface plate 12, and it is possible to suppress a decrease in the processing accuracy of the disk-shaped substrate 100. In this embodiment, as described above, multiple hole groups 33 are arranged in the circumferential direction of the flange 29, so it is possible to change the load acting on the upper surface plate 20 at each portion of the flange 29 in the circumferential direction. As a result, it is possible to correct the flatness of the lower surface of the upper surface plate 20 with high precision. This suppresses a decrease in the processing accuracy of polishing or grinding performed by the upper surface plate 20 and the lower surface plate 12. Furthermore, it is possible to realize high-precision processing using the manufacturing apparatus for a long period of time.

[0033] <Modification of Manufacturing Method> The manufacturing method of the disk-shaped substrate of the present disclosure is not limited to the above-described example, and may include at least a measurement step and a modification step. The manufacturing method of this embodiment is performed using the manufacturing apparatus 10 described above, but may also be performed without using the manufacturing apparatus 10 described above. In this disclosure, the manufacturing method of the disk-shaped substrate 200 may include one or more other commonly known processes depending on the type of disk-shaped substrate 200. In the manufacturing method of this embodiment, the polishing step is performed using the manufacturing apparatus 10, but this is not limited to this. A grinding step may also be performed using the manufacturing apparatus 10. In this embodiment, the manufacturing apparatus 10 may be used to perform, for example, either the grinding step or the polishing step, or both.

[0034] The disclosure of Japanese Patent Application No. 2024-109913, filed on July 8, 2024, is incorporated herein by reference in its entirety. All publications, patent applications, and technical standards mentioned herein are incorporated herein by reference to the same extent as if each individual publication, patent application, and technical standard was specifically and individually indicated to be incorporated by reference.

Claims

1. A manufacturing device for disk-shaped substrates comprising: a lower surface plate on which a disk-shaped substrate is placed; an upper surface plate which rotates with the disk-shaped substrate sandwiched between said lower surface plate and said upper surface plate and which polishes or grinds said disk-shaped substrate; a shaft part which is provided above said upper surface plate and extends in the vertical direction; a flange which protrudes radially from a lower part of said shaft part and has a plurality of through holes which penetrate vertically and are arranged in said radial direction; and fastening members which fasten said flange to said upper surface plate through said through holes and which are replaceable into said plurality of through holes.

2. The disk-shaped substrate manufacturing device according to claim 1, wherein the plurality of through holes have fastening points where the fastening members are fastened and non-fastening points where the fastening members are not fastened, and the fastening members fastened at the fastening points can be transferred to the non-fastening points.

3. The disk-shaped substrate manufacturing device according to claim 1, wherein the plurality of through holes are arranged in a circumferential direction of the flange.

4. A method for manufacturing a disk-shaped substrate, comprising: a first step in which an upper surface plate rotates with a disk-shaped substrate sandwiched between it and a lower surface plate, and polishes or grinds the disk-shaped substrate; and a second step in which the fastening position of a fastening member is changed depending on the flatness of the lower surface of the upper surface plate, wherein the fastening member fastens a flange to the upper surface plate through a through hole, the flange is a flange that protrudes radially from a lower part of a shaft portion, and a plurality of through holes that penetrate in the vertical direction are arranged in the radial direction, and the shaft portion is provided above the upper surface plate and extends in the vertical direction.

5. A method for manufacturing a disk-shaped substrate as described in claim 4, wherein the plurality of through holes have fastening points where the fastening members are fastened and non-fastening points where the fastening members are not fastened, and in the second step, the fastening positions of the fastening members are changed by transferring the fastening members fastened at the fastening points to the non-fastening points.

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