JP2012059307A - Disk-like substrate inner diameter measuring instrument, disk-like substrate inner diameter measuring method and method for manufacturing disk-like substrate - Google Patents

Disk-like substrate inner diameter measuring instrument, disk-like substrate inner diameter measuring method and method for manufacturing disk-like substrate Download PDF

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JP2012059307A
JP2012059307A JP2010198511A JP2010198511A JP2012059307A JP 2012059307 A JP2012059307 A JP 2012059307A JP 2010198511 A JP2010198511 A JP 2010198511A JP 2010198511 A JP2010198511 A JP 2010198511A JP 2012059307 A JP2012059307 A JP 2012059307A
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disk
substrate
inner diameter
shaped substrate
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Masanobu Itaya
旬展 板谷
Hiroaki Ikeda
宏明 池田
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Hoya Corp
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Abstract

PROBLEM TO BE SOLVED: To provide a disk-like substrate inner diameter measuring instrument capable of measuring an inner diameter with high accuracy without deteriorating a yield about the entire manufactured substrate for a magnetic disk, and to provide a disk-like substrate inner diameter measuring method and a method for manufacturing the disk-like substrate.SOLUTION: A laser displacement gauge (measuring instrument) 100 includes: a line laser light source 110 for irradiating a line laser 112 to a main surface of a disk-like substrate 200; a substrate holder 130 for supporting the disk-like substrate 200; a lifting and lowering part 140 for lifting and lowering the substrate holder 130 so as to make the line laser 112 pass through a circular hole 210 of the disk-like substrate 200; a laser sensor 120 for receiving the line laser 112 reflected on or passing through the disk-like substrate 200 during lifting or lowering the substrate holder 130 to acquire the light quantity distribution thereof; and an inner diameter measuring part 150 for measuring the inner diameter of the circular hole 210 from the light quantity distribution acquired by the laser sensor 120. The substrate holder 130 supports the disk-like substrate 200 such that a substrate posture during measurement is placed within the range of a predetermined angle from a vertical line with respect to a ground surface.

Description

本発明は、ハードディスクドライブ装置に搭載される磁気ディスク用基板の内径等の寸法を測定する円板状基板内径測定装置、円板状基板内径測定方法及び円板状基板の製造方法に関する。   The present invention relates to a disk-shaped substrate inner diameter measuring device, a disk-shaped substrate inner diameter measuring method, and a method for manufacturing a disk-shaped substrate that measure dimensions such as the inner diameter of a magnetic disk substrate mounted on a hard disk drive.

ハードディスクドライブ装置(HDD装置)に搭載される磁気記録媒体として磁気ディスクがある。磁気ディスクは、アルミニウム−マグネシウム合金などで構成された金属板上にNiP膜を被着した基板、ガラス基板、セラミックス基板上に磁性層や保護層を積層したりして作製される。従来では、磁気ディスク用の基板としてアルミニウム合金基板が広く用いられていたが、近年の磁気ディスクの小型化、薄板化、高密度記録化に伴って、アルミニウム合金基板に比べて表面の平坦度や薄板での強度に優れたガラス基板が用いられるようになってきている。   There is a magnetic disk as a magnetic recording medium mounted on a hard disk drive device (HDD device). A magnetic disk is manufactured by laminating a magnetic layer or a protective layer on a substrate, a glass substrate, or a ceramic substrate on which a NiP film is deposited on a metal plate made of an aluminum-magnesium alloy or the like. Conventionally, an aluminum alloy substrate has been widely used as a substrate for a magnetic disk. However, with recent downsizing, thinning, and high-density recording of magnetic disks, surface flatness and A glass substrate having excellent strength with a thin plate has been used.

このような磁気ディスク用基板は、形状加工工程及び第1ラッピング工程(第1研削工程);端部形状工程(中央部に円孔(穴部)を形成するコアリング工程、端部(外周端部及び内周端部)に面取り面を形成するチャンファリング工程(面取り面形成工程));端面研磨工程(外周端部及び内周端部);第2ラッピング工程(第2研削工程);主表面研磨工程(第1及び第2研磨工程);化学強化工程などの工程を経て製造される。   Such a magnetic disk substrate includes a shape processing step and a first lapping step (first grinding step); an end shape step (a coring step in which a circular hole (hole) is formed in the central portion; Chamfering step (chamfered surface forming step)) for forming a chamfered surface on the outer peripheral edge and the inner peripheral edge); end surface polishing step (outer peripheral edge and inner peripheral edge); second lapping step (second grinding step); Surface polishing process (first and second polishing processes); manufactured through processes such as a chemical strengthening process.

磁気ディスク用基板の製造後は、表面の粗さや端部形状などの測定、パーティクルなどの欠陥を検出する測定、基板の中央に形成した円孔の径を測定する検査など各種検査が行われる。表面の粗さや端部形状などの測定では、触針式測定機や光学式/干渉系測定機などが用いられ、欠陥検出には光学式自動外観検査(AOI;Automated Optical Inspection)などが用いられている。また、基板の中央に形成した円孔の径を測定する検査にはマイクロメータや内径測定装置(特許文献1)などが用いられている。   After the manufacture of the magnetic disk substrate, various inspections such as measurement of surface roughness and edge shape, detection of defects such as particles, and inspection of measuring the diameter of a circular hole formed in the center of the substrate are performed. For measurement of surface roughness and edge shape, stylus type measuring instruments and optical / interferometric measuring instruments are used, and optical automatic appearance inspection (AOI) is used for defect detection. ing. Further, a micrometer, an inner diameter measuring device (Patent Document 1), or the like is used for an inspection for measuring the diameter of a circular hole formed in the center of the substrate.

特許文献1で開示された内径測定装置は、ライン光を中央に円孔が形成された円板状基板の主表面に照射するライン光源と、前記円板状基板を支持する基板ホルダと、前記ライン光が前記円板状基板の円孔を通過するように前記基板ホルダ又は前記ライン光源を昇降させる昇降部と、前記昇降中、前記円板状基板を反射又は通過したライン光を受光し、その光量分布を取得する受光部と、前記受光部が取得した光量分布から、前記円板状基板の円孔の弦の長さを取得し、最大の弦の長さを円孔の内径とする内径測定部とを含み、前記基板ホルダは、円板状基板を複数の支点で支持する。   An inner diameter measuring device disclosed in Patent Document 1 includes a line light source that irradiates a main surface of a disk-shaped substrate having a circular hole formed in the center thereof, a substrate holder that supports the disk-shaped substrate, An elevating part that elevates and lowers the substrate holder or the line light source so that line light passes through a circular hole of the disk-shaped substrate; and during the elevating and receiving line light reflected or passed through the disk-shaped substrate; From the light receiving unit that acquires the light amount distribution and the light amount distribution acquired by the light receiving unit, the chord length of the circular hole of the disk-shaped substrate is acquired, and the maximum chord length is set as the inner diameter of the circular hole. The substrate holder supports the disc-shaped substrate at a plurality of fulcrums.

特開2009−014361号公報JP 2009-014361 A

ところで、磁気ディスク用基板の内径を測定する検査においてマイクロメータを用いた場合、測定の際に磁気ディスク用基板に押し当てることになるので、内径部分に傷を付けてしまう虞がある。傷を付けてしまうようなことがあると、製品として出荷できなくなるため、全数検査ができない。また、この検査では人手を要するので、磁気ディスク用基板の出荷保証をするには測定のバラツキが大きいという問題がある。これに対し、内径測定装置では、磁気ディスク用基板の円孔の内径測定を非接触で行えるので、全数検査が可能であり、またマイクロメータよりも測定精度を高くとれるので、測定値のバラツキを低く抑えることができる。   By the way, when a micrometer is used in the test for measuring the inner diameter of the magnetic disk substrate, it is pressed against the magnetic disk substrate at the time of measurement, so that there is a risk of scratching the inner diameter portion. If it is damaged, it will not be possible to ship as a product, and 100% inspection will not be possible. Further, since this inspection requires manpower, there is a problem that measurement variation is large in order to guarantee the shipment of the magnetic disk substrate. On the other hand, the inner diameter measuring device can measure the inner diameter of the circular hole of the magnetic disk substrate in a non-contact manner, so that 100% inspection is possible and the measurement accuracy is higher than that of a micrometer. It can be kept low.

しかしながら、特許文献1に記載されている内径測定装置では、円板状基板を複数の支点で支持した状態の基板ホルダを測定装置の接地面に対して鉛直方向に昇降させて内径を測定しているところ、円板状基板の昇降開始時に、昇降の駆動部のモータ等の振動により円板状基板が揺れてしまい、円板状基板が揺れている状態で内径を測ることとなり、同じ基板を複数回測定しても測定ごとに測定値にバラツキが生じるという問題が生じている。   However, in the inner diameter measuring apparatus described in Patent Document 1, the inner diameter is measured by moving the substrate holder in a state where the disk-shaped substrate is supported by a plurality of fulcrums vertically with respect to the ground plane of the measuring apparatus. However, at the start of raising and lowering the disk-shaped substrate, the disk-shaped substrate is shaken by the vibration of the motor of the lifting and lowering drive unit, and the inner diameter is measured while the disk-shaped substrate is shaking, and the same substrate is There is a problem that even if the measurement is performed a plurality of times, the measurement value varies for each measurement.

円孔は、磁気ディスクをHDD(Hard Disk Drive)に組み込むに際してスピンドル(回転軸)が取り付けられて回転されるため、重要な要素である。内径がスピンドルの径よりも小さければ、スピンドルを取り付ける際に内周端面(円孔の端面)に欠けが生じ、剥離した破片(コンタミ)が主表面(記録面)に付着して、記録ヘッドに損傷を与えたり、或いはその破片が内径部分に実施されるスピンドルと磁気ディスクを固定するクランピングへ不具合を与え、回転精度へ悪影響を与えたりするおそれがある。内径がスピンドルの径よりも大きければ、スピンドルの回転軸が磁気ディスクの重心に対して偏心してしまい、高速回転させると振動や騒音、読み書きエラーの原因となったりするおそれがある。特に、更なる高密度記録に対応させるべくBPM(ビットパターンドメディア)等の磁気ディスクに対しては、より正確な内径測定が求められると考えられる。   The circular hole is an important element because a spindle (rotary shaft) is attached and rotated when the magnetic disk is incorporated in an HDD (Hard Disk Drive). If the inner diameter is smaller than the diameter of the spindle, the inner peripheral end face (end face of the circular hole) is chipped when the spindle is mounted, and the separated debris (contamination) adheres to the main surface (recording face), and is attached to the recording head. There is a risk that damage may be caused, or the broken piece may cause a defect in the clamping that fixes the spindle and the magnetic disk, which is performed on the inner diameter portion, and adversely affects the rotation accuracy. If the inner diameter is larger than the diameter of the spindle, the rotation axis of the spindle is decentered with respect to the center of gravity of the magnetic disk, and if it is rotated at a high speed, vibration, noise and read / write errors may occur. In particular, it is considered that a more accurate inner diameter measurement is required for a magnetic disk such as a BPM (bit patterned medium) in order to cope with higher density recording.

本発明はかかる点に鑑みてなされたものであり、製造した磁気ディスク用基板の全てについて、高精度で内径測定を行うことができ、また内径以外に外径や厚みも測定することができる円板状基板内径測定装置、円板状基板内径測定方法及び円板状基板の製造方法を提供することを目的とする。   The present invention has been made in view of the above points, and it is possible to measure the inner diameter with high accuracy for all of the manufactured magnetic disk substrates and to measure the outer diameter and thickness in addition to the inner diameter. An object of the present invention is to provide a plate-shaped substrate inner diameter measuring device, a disk-shaped substrate inner diameter measuring method, and a method for manufacturing a disk-shaped substrate.

本発明の円板状基板内径測定装置は、中央に円孔が形成された円板状基板の内径を測定する円板状基板内径測定装置であって、ライン光を前記円板状基板の主表面上に照射するライン光源と、前記円板状基板を支持する基板ホルダと、前記ライン光が前記円板状基板の前記円孔を通過するように前記基板ホルダを昇降させる昇降部と、前記円板状基板の昇降中、前記円板状基板を反射又は通過したライン光を受光し、その光量分布を取得する受光部と、前記受光部が取得した光量分布から、前記円板状基板の円孔の弦の長さを取得し、最大の弦の長さを円孔の内径とする測定部と、を具備し、前記円板状基板を支持した基板ホルダは、該測定装置の接地面に対する鉛直線に対して0°を超え10°以下傾けた状態で昇降させることを特徴とする。   The disk-shaped substrate inner diameter measuring apparatus of the present invention is a disk-shaped substrate inner diameter measuring apparatus for measuring the inner diameter of a disk-shaped substrate having a circular hole formed in the center, and the line light is mainly emitted from the disk-shaped substrate. A line light source for irradiating the surface, a substrate holder for supporting the disk-shaped substrate, a lifting unit for moving the substrate holder up and down so that the line light passes through the circular hole of the disk-shaped substrate, and While the disk-shaped substrate is moved up and down, the line-shaped light reflected or passed through the disk-shaped substrate is received, and a light receiving unit that acquires the light amount distribution, and the light amount distribution acquired by the light receiving unit, A measurement unit that obtains the length of the chord of the circular hole and sets the maximum chord length as the inner diameter of the circular hole, and the substrate holder that supports the disk-shaped substrate is a ground plane of the measurement device. It is raised and lowered in a state tilted over 0 ° and 10 ° or less with respect to the vertical line with respect to .

この構成によれば、円板状基板の測定時の姿勢を地面に対して鉛直から所定の角度の範囲で傾けたので、円板状基板が重力によって確実に基板ホルダに固定され、振動による測定のバラツキを低く抑えることができる。なお、角度が10°を超えると、基板ホルダから円板状基板が落下してしまう。   According to this configuration, since the posture at the time of measurement of the disk-shaped substrate is tilted with respect to the ground within a predetermined angle range from the vertical, the disk-shaped substrate is securely fixed to the substrate holder by gravity and measured by vibration. Can be kept low. When the angle exceeds 10 °, the disc-shaped substrate falls from the substrate holder.

本発明の円板状基板内径測定装置において、前記昇降部は、モータと、該モータの回転運動を直線運動に変換する変換機構とを具備し、前記モータは、サーボモータ又はリニアモータであることを特徴とする。この構成によれば、モータと変換機構からなる簡易な構成とすることで、振動を発生する要素を最小限に抑えることができ、振動による測定のバラツキを低く抑えることができる。   In the disk-shaped substrate inner diameter measuring apparatus according to the present invention, the elevating unit includes a motor and a conversion mechanism that converts the rotational motion of the motor into a linear motion, and the motor is a servo motor or a linear motor. It is characterized by. According to this configuration, by adopting a simple configuration including the motor and the conversion mechanism, it is possible to minimize the elements that generate vibration, and to suppress measurement variations due to vibration.

本発明の円板状基板内径測定装置において、前記昇降部を構成する各種パーツの結合部分に弾性部材を用いたブッシュを設けたことを特徴とする。この構成によれば、昇降部を構成する各種パーツにおける振動を抑えることができる。   In the disk-shaped substrate inner diameter measuring apparatus according to the present invention, a bush using an elastic member is provided at a connecting portion of various parts constituting the elevating unit. According to this structure, the vibration in the various parts which comprise the raising / lowering part can be suppressed.

本発明の円板状基板厚さ測定装置は、中央に円孔が形成された円板状基板の厚さを測定する円板状基板厚さ測定装置であって、ライン光を前記基板に照射するライン光源と、前記基板を支持する基板ホルダと、前記ライン光が前記基板に照射されるように前記基板ホルダを昇降させる昇降部と、前記基板の昇降中、前記基板の表面及び裏面からの反射光を受光する受光部と、前記基板の表面及び裏面からの反射光の干渉状態を計測することで前記基板の厚さを測定する測定部と、を具備することを特徴とする。この構成によれば、円板状基板の厚さを測定することができる。   The disk-shaped substrate thickness measuring apparatus of the present invention is a disk-shaped substrate thickness measuring apparatus for measuring the thickness of a disk-shaped substrate having a circular hole formed in the center, and irradiates the substrate with line light. A line light source, a substrate holder that supports the substrate, an elevating unit that elevates and lowers the substrate holder so that the line light is irradiated on the substrate, and from the front and back surfaces of the substrate during the elevating and lowering of the substrate A light receiving unit that receives reflected light and a measurement unit that measures the thickness of the substrate by measuring an interference state of reflected light from the front surface and the back surface of the substrate. According to this configuration, the thickness of the disk-shaped substrate can be measured.

本発明の円板状基板内径測定方法は、中央に円孔が形成された円板状基板の寸法を測定する円板状基板内径測定方法であって、ライン光を前記円板状基板の主表面に照射するライン光照射工程と、基板ホルダによって前記円板状基板を支持する基板支持工程と、前記ライン光が前記円板状基板の前記円孔を通過するように前記基板ホルダを昇降させる昇降工程と、前記円板状基板の昇降中、前記円板状基板を反射又は通過したライン光を受光し、その光量分布を取得する受光工程と、前記受光工程で取得した光量分布から、前記円板状基板の円孔の弦の長さを取得し、最大の弦の長さを円孔の内径とする測定工程と、を具備し、前記円板状基板を支持した基板ホルダは、該測定装置の接地面に対する鉛直線に対して0°を超え10°以下傾けた状態で昇降させることを特徴とする。   The disk-shaped substrate inner diameter measuring method of the present invention is a disk-shaped substrate inner diameter measuring method for measuring a dimension of a disk-shaped substrate having a circular hole formed in the center, and the line light is mainly emitted from the disk-shaped substrate. A line light irradiation step for irradiating the surface, a substrate support step for supporting the disk-shaped substrate by a substrate holder, and raising and lowering the substrate holder so that the line light passes through the circular hole of the disk-shaped substrate. From the raising / lowering step, and during the raising / lowering of the disk-shaped substrate, the line light reflected or passed through the disk-shaped substrate is received, the light receiving step for obtaining the light amount distribution, and the light amount distribution obtained in the light receiving step, Measuring the length of the chord of the circular hole of the disk-shaped substrate and setting the maximum chord length as the inner diameter of the circular hole, and the substrate holder that supports the disk-shaped substrate comprises: Inclined by more than 0 ° and not more than 10 ° with respect to the vertical line to the ground plane of the measuring device It is characterized by being raised and lowered in a state.

この方法によれば、円板状基板の測定時の姿勢を地面に対して鉛直から所定の角度の範囲で傾けたので、円板状基板が重力によって確実に基板ホルダに固定され、振動による測定のバラツキを低く抑えることができる。   According to this method, since the posture at the time of measurement of the disk-shaped substrate is tilted with respect to the ground within a predetermined angle range from the vertical, the disk-shaped substrate is securely fixed to the substrate holder by gravity, and measurement by vibration Can be kept low.

本発明の円板状基板の製造方法は、上記発明の円板状基板内径測定方法を用いて円板状基板の内径を測定する内径測定工程と、前記測定した内径の値に応じて良品又は不良品のいずれかの判断を行う品質検査工程とを具備することを特徴とする。この方法によれば、品質が良く信頼性の高い円板状基板を製造することができる。   The manufacturing method of the disk-shaped substrate of the present invention includes an inner diameter measuring step of measuring the inner diameter of the disk-shaped substrate using the disk-shaped substrate inner diameter measuring method of the present invention, and a non-defective product according to the value of the measured inner diameter. And a quality inspection process for determining any defective product. According to this method, it is possible to manufacture a disc-shaped substrate with high quality and high reliability.

本発明の磁気ディスク製造方法は、上記発明の円板状基板の製造方法を用いて製造した円板状基板に少なくとも磁性層を形成することを特徴とする。この方法によれば、品質が良く信頼性の高い磁気ディスクを製造することができる。   The magnetic disk manufacturing method of the present invention is characterized in that at least a magnetic layer is formed on a disk-shaped substrate manufactured using the method for manufacturing a disk-shaped substrate of the above invention. According to this method, a magnetic disk with high quality and high reliability can be manufactured.

本発明の円板状基板内径測定装置は、製造した磁気ディスク用基板の全てについて、歩留まりを悪化させることなく高精度で内径測定を行うことができ、また内径以外に外径や厚みも測定することができる。   The disc-shaped substrate inner diameter measuring apparatus of the present invention can measure the inner diameter with high accuracy without deteriorating the yield of all the manufactured magnetic disk substrates, and also measures the outer diameter and thickness in addition to the inner diameter. be able to.

本発明の実施の形態に係る円板状基板内径測定装置の概略構成を示す図である。It is a figure which shows schematic structure of the disk shaped board | substrate inner diameter measuring apparatus which concerns on embodiment of this invention. 図1の円板状基板内径測定装置の昇降部の概略構成を示す図である。It is a figure which shows schematic structure of the raising / lowering part of the disk-shaped board | substrate inner diameter measuring apparatus of FIG. 図1の円板状基板内径測定装置の基板ホルダの爪部を示す断面図である。It is sectional drawing which shows the nail | claw part of the substrate holder of the disk-shaped board | substrate inner diameter measuring apparatus of FIG. 図1の円板状基板内径測定装置において、基板ホルダを鉛直方向に昇降させた場合の内径測定値の3σと、10°傾けた場合の内径測定値の3σを示すグラフである。2 is a graph showing 3σ of an inner diameter measurement value when the substrate holder is moved up and down in the vertical direction and 3σ of an inner diameter measurement value when tilted by 10 ° in the disc-shaped substrate inner diameter measurement apparatus of FIG. 図1の円板状基板内径測定装置を用いた円板状基板内径測定方法を説明するためのフローチャートである。It is a flowchart for demonstrating the disk-shaped board | substrate inner-diameter measuring method using the disk-shaped board | substrate inner diameter measuring apparatus of FIG.

以下、本発明の実施の形態について添付図面を参照して詳細に説明する。本実施の形態においては、磁気ディスク用基板がガラス基板である場合について説明する。   Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the present embodiment, the case where the magnetic disk substrate is a glass substrate will be described.

ここで、磁気ディスク用基板の材料としては、アルミノシリケートガラス、ソーダライムガラス、ボロシリケートガラス、アルミニウム−マグネシウム合金などを用いることができる。特に、化学強化を施すことができ、また主表面の平坦性及び基板強度において優れた磁気ディスク用基板を提供することができるという点で、アルミノシリケートガラスを好ましく用いることができる。   Here, as the material for the magnetic disk substrate, aluminosilicate glass, soda lime glass, borosilicate glass, aluminum-magnesium alloy, or the like can be used. In particular, aluminosilicate glass can be preferably used in that it can be chemically strengthened and can provide a magnetic disk substrate excellent in flatness of the main surface and substrate strength.

磁気ディスク用基板の製造工程は、形状加工工程及び第1ラッピング工程;端部形状工程(穴部を形成するコアリング工程、端部(外周端部及び/又は内周端部)に面取り面を形成するチャンファリング工程(面取り面形成工程));端面研磨工程(外周端部及び内周端部);第2ラッピング工程;主表面研磨工程(第1及び第2研磨工程);化学強化工程などの工程を含む。   The manufacturing process of the magnetic disk substrate includes a shape processing step and a first lapping step; an end shape step (a coring step for forming a hole, a chamfered surface at an end (outer peripheral end and / or inner peripheral end)) Chamfering step to be formed (chamfered surface forming step)); end surface polishing step (outer peripheral end and inner peripheral end); second lapping step; main surface polishing step (first and second polishing step); chemical strengthening step, etc. These steps are included.

以下に、磁気ディスク用基板の製造工程の各工程について説明する。
(1)形状加工工程及び第1ラッピング工程
まず、形状加工工程においては、板状ガラスの表面をラッピング(研削)加工してガラス母材とし、このガラス母材を切断してガラスディスクを切り出す。板状ガラスとしては、様々な板状ガラスを用いることができる。この板状ガラスは、例えば、溶融ガラスを材料として、プレス法やフロート法、ダウンドロー法、リドロー法、フュージョン法など、公知の製造方法を用いて製造することができる。これらの方法うち、プレス法を用いれば、板状ガラスを廉価に製造することができる。
Below, each process of the manufacturing process of the board | substrate for magnetic discs is demonstrated.
(1) Shape processing step and first lapping step First, in the shape processing step, the surface of the sheet glass is lapped (ground) to form a glass base material, and the glass base material is cut to cut out a glass disk. Various plate glasses can be used as the plate glass. This plate-like glass can be manufactured by using a known manufacturing method such as a press method, a float method, a downdraw method, a redraw method, or a fusion method using a molten glass as a material. Of these methods, if a press method is used, a sheet glass can be produced at a low cost.

第1ラッピング工程においては、板状ガラスの両主表面をラッピング加工し、ディスク状のガラス基材とする。このラッピング加工は、遊星歯車機構を利用した両面ラッピング装置により、アルミナ系遊離砥粒を用いて行うことができる。具体的には、板状ガラスの両面に上下からラップ定盤を押圧させ、遊離砥粒を含む研削液を板状ガラスの主表面上に供給し、これらを相対的に移動させてラッピング加工を行う。このラッピング加工により、平坦な主表面を有するガラス基板を得ることができる。   In the first lapping step, both main surfaces of the sheet glass are lapped to form a disk-shaped glass substrate. This lapping process can be performed using alumina free abrasive grains with a double-sided lapping apparatus using a planetary gear mechanism. Specifically, the lapping platen is pressed on both sides of the plate glass from above and below, the grinding liquid containing free abrasive grains is supplied onto the main surface of the plate glass, and these are moved relative to each other for lapping. Do. By this lapping process, a glass substrate having a flat main surface can be obtained.

(2)端部形状工程(穴部を形成するコアリング工程、端部(外周端部及び内周端部)に面取り面を形成するチャンファリング工程(面取り面形成工程))
コアリング工程においては、例えば、円筒状のダイヤモンドドリルを用いて、このガラス基板の中心部に内孔を形成し、円環状のガラス基板とする。チャンファリング工程においては、内周端面及び外周端面をダイヤモンド砥石によって研削し、所定の面取り加工を施す。
(2) End shape process (coring process for forming a hole, chamfering process for forming a chamfered surface at the end (outer peripheral end and inner peripheral end) (chamfered surface forming process))
In the coring step, for example, an inner hole is formed at the center of the glass substrate using a cylindrical diamond drill to obtain an annular glass substrate. In the chamfering step, the inner peripheral end surface and the outer peripheral end surface are ground with a diamond grindstone, and a predetermined chamfering process is performed.

(3)第2ラッピング工程
第2ラッピング工程においては、得られたガラス基板の両主表面について、第1ラッピング工程と同様に、第2ラッピング加工を行う。この第2ラッピング工程を行うことにより、前工程である切り出し工程や端面研磨工程において主表面に形成された微細な凹凸形状を予め除去しておくことができ、後続の主表面に対する研磨工程を短時間で完了させることができるようになる。
(3) Second Lapping Step In the second lapping step, the second lapping process is performed on both main surfaces of the obtained glass substrate in the same manner as in the first lapping step. By performing this second lapping step, it is possible to remove in advance the fine unevenness formed on the main surface in the cutting step and end surface polishing step, which are the previous steps, and shorten the subsequent polishing step on the main surface. Will be able to be completed in time.

(4)端面研磨工程
端面研磨工程においては、ガラス基板の外周端面及び内周端面について、ブラシ研磨方法により、鏡面研磨を行う。このとき、研磨砥粒としては、例えば、酸化セリウム砥粒を含むスラリー(遊離砥粒)を用いることができる。この端面研磨工程により、ガラス基板の端面は、ナトリウムやカリウムの析出の発生を防止できる鏡面状態になる。
(4) End surface polishing step In the end surface polishing step, the outer peripheral end surface and the inner peripheral end surface of the glass substrate are mirror-polished by a brush polishing method. At this time, as the abrasive grains, for example, a slurry containing cerium oxide abrasive grains (free abrasive grains) can be used. By this end face polishing step, the end face of the glass substrate is in a mirror state that can prevent the precipitation of sodium and potassium.

(5)主表面研磨工程(第1研磨工程)
主表面研磨工程として、まず第1研磨工程を施す。第1研磨工程は、前述のラッピング工程で主表面に残留したキズや歪みの除去を主たる目的とする工程である。この第1研磨工程においては、遊星歯車機構を有する両面研磨装置により、硬質樹脂ポリッシャを用いて、主表面の研磨を行う。研磨剤としては、酸化セリウム砥粒を用いることができる。
(5) Main surface polishing step (first polishing step)
As the main surface polishing step, first, a first polishing step is performed. The first polishing process is a process whose main purpose is to remove scratches and distortions remaining on the main surface in the lapping process described above. In the first polishing step, the main surface is polished using a hard resin polisher by a double-side polishing apparatus having a planetary gear mechanism. As the abrasive, cerium oxide abrasive grains can be used.

(6)化学強化工程
化学強化工程においては、前述のラッピング工程及び研磨工程を終えたガラス基板に化学強化を施す。化学強化に用いる化学強化液としては、例えば、硝酸カリウム(60%)と硝酸ナトリウム(40%)の混合溶液などを用いることができる。化学強化においては、化学強化液を300℃〜400℃に加熱し、洗浄済みのガラス基板を200℃〜300℃に予熱し、化学強化溶液中に3時間〜4時間浸漬することによって行う。この浸漬の際には、ガラス基板の表面全体が化学強化されるようにするため、複数のガラス基板が端面で保持されるように、ホルダに収納した状態で行うことが好ましい。
(6) Chemical strengthening step In the chemical strengthening step, the glass substrate that has been subjected to the lapping step and the polishing step described above is chemically strengthened. As a chemical strengthening solution used for chemical strengthening, for example, a mixed solution of potassium nitrate (60%) and sodium nitrate (40%) can be used. In the chemical strengthening, the chemical strengthening solution is heated to 300 ° C. to 400 ° C., the cleaned glass substrate is preheated to 200 ° C. to 300 ° C., and immersed in the chemical strengthening solution for 3 hours to 4 hours. In soaking, in order to chemically strengthen the entire surface of the glass substrate, the immersion is preferably performed in a state of being accommodated in a holder so that the plurality of glass substrates are held at the end surfaces.

このように、化学強化溶液に浸漬処理することによって、ガラス基板の表層のリチウムイオン及びナトリウムイオンが、化学強化溶液中の相対的にイオン半径の大きなナトリウムイオン及びカリウムイオンにそれぞれ置換され、ガラス基板が強化される。   Thus, by immersing in the chemical strengthening solution, the lithium ions and sodium ions in the surface layer of the glass substrate are respectively replaced with sodium ions and potassium ions having a relatively large ion radius in the chemical strengthening solution. Will be strengthened.

(7)主表面研磨工程(最終研磨工程)
次に、最終研磨工程として、第2研磨工程を施す。第2研磨工程は、主表面を鏡面状に仕上げることを目的とする工程である。第2研磨工程においては、遊星歯車機構を有する両面研磨装置により、軟質発泡樹脂ポリッシャを用いて、両主表面の鏡面研磨を行う。スラリーとしては、第1研磨工程で用いた酸化セリウム砥粒よりも微細な酸化セリウム砥粒やコロイダルシリカなどを用いることがきる。
(7) Main surface polishing process (final polishing process)
Next, a second polishing process is performed as a final polishing process. The second polishing step is a step aimed at finishing the main surface into a mirror surface. In the second polishing step, both main surfaces are mirror-polished using a soft foam resin polisher by a double-side polishing apparatus having a planetary gear mechanism. As the slurry, cerium oxide abrasive grains or colloidal silica finer than the cerium oxide abrasive grains used in the first polishing step can be used.

(8)内径測定工程
上記(7)主表面研磨工程までで完成されたガラス基板に対して、図1に示す円板状基板内径測定装置100を用いてガラス基板の内径を測定する。この測定で顧客へ出荷できる品質が得られるものを選別してディスクケースに収納する。
(8) Inner Diameter Measuring Step With respect to the glass substrate completed up to the above (7) main surface polishing step, the inner diameter of the glass substrate is measured using the disc-like substrate inner diameter measuring apparatus 100 shown in FIG. A product that can be shipped to a customer with this measurement is selected and stored in a disk case.

ここで、円板状基板内径測定装置100を詳細に説明する。図1において、円板状基板内径測定装置100は、中央に円孔210が形成された円板状基板200の内径を測定するものであり、ラインレーザ112を円板状基板200の主表面上に照射するラインレーザ光源(ライン光源)110と、円板状基板200を支持する基板ホルダ130と、ラインレーザ112が円板状基板200の円孔210を通過するように基板ホルダ130を昇降させる昇降部140と、円板状基板200の昇降中、円板状基板200を反射または通過したラインレーザ112を受光し、その光量分布を取得するレーザセンサ(受光部)120と、レーザセンサ120が取得した光量分布から、円板状基板200の円孔の弦の長さを取得し、最大の弦の長さを円孔の内径とする内径測定部(測定部)150と、を備えている。   Here, the disk-shaped substrate inner diameter measuring apparatus 100 will be described in detail. In FIG. 1, a disk-shaped substrate inner diameter measuring apparatus 100 measures the inner diameter of a disk-shaped substrate 200 having a circular hole 210 formed in the center, and a line laser 112 is placed on the main surface of the disk-shaped substrate 200. A line laser light source (line light source) 110 that irradiates the substrate, a substrate holder 130 that supports the disk-shaped substrate 200, and the substrate holder 130 is moved up and down so that the line laser 112 passes through the circular hole 210 of the disk-shaped substrate 200. A laser sensor (light receiving unit) 120 that receives the line laser 112 reflected or passed through the disk-shaped substrate 200 and acquires the light amount distribution during the lifting / lowering unit 140 and the disk-shaped substrate 200 is moved up and down. An inner diameter measuring unit (measuring unit) 150 that acquires the chord length of the circular hole of the disk-shaped substrate 200 from the acquired light amount distribution and uses the maximum chord length as the inner diameter of the circular hole. That.

基板ホルダ130は、図2に示すように円板状基板200を3個の支点220A〜220Cで支持する。すなわち、基板ホルダ130の3個の爪部130a〜130cで支持する。爪部130a〜130cのそれぞれには、図3に示すようにV字状の溝が形成されており、このV字溝により、円板状基板200をその姿勢が地面に対し鉛直から±10°の範囲に入るように支持する。このV字溝は、重力を利用して円板状基板200の支持を確実にするものである。なお、円板状基板200の保持を3点で行うことで、円板状基板200との接触面積を小さくでき、パーティクルの付着リストを軽減できる利点がある。   As shown in FIG. 2, the substrate holder 130 supports the disc-shaped substrate 200 with three fulcrums 220 </ b> A to 220 </ b> C. That is, it is supported by the three claw portions 130 a to 130 c of the substrate holder 130. Each of the claw portions 130a to 130c is formed with a V-shaped groove as shown in FIG. 3, and this V-shaped groove allows the disk-shaped substrate 200 to be placed at a position ± 10 ° from the vertical with respect to the ground. Support to be in the range. This V-shaped groove ensures the support of the disk-shaped substrate 200 using gravity. Note that holding the disk-shaped substrate 200 at three points has an advantage that the contact area with the disk-shaped substrate 200 can be reduced and the particle adhesion list can be reduced.

図4は、円板状基板内径測定装置100において、基板ホルダ130を鉛直方向に昇降させた場合の内径測定値の3σと、10°傾けた場合の内径測定値の3σを示す図である。同図は、9枚の円板状基板(Disk)を1つずつ測定した場合の3σである。CV1は、基板ホルダ130を0°傾けたときの3σ、CV2は基板ホルダ130を10°傾けたときの3σである。基板ホルダ130を10°傾けることにより、傾けない場合に比べて飛躍的に3σの値が改善されていることがわかる。   FIG. 4 is a diagram showing 3σ of the measured inner diameter when the substrate holder 130 is moved up and down in the vertical direction and 3σ of the measured inner diameter when tilted by 10 ° in the disc-shaped substrate inner diameter measuring apparatus 100. The figure shows 3σ when nine disk-shaped substrates (Disks) are measured one by one. CV1 is 3σ when the substrate holder 130 is tilted by 0 °, and CV2 is 3σ when the substrate holder 130 is tilted by 10 °. It can be seen that by inclining the substrate holder 130 by 10 °, the value of 3σ is drastically improved as compared with the case where the substrate holder 130 is not inclined.

図2において、昇降部140は、モータ140Aと、モータ140Aの回転運動を直線運動に変換する変換機構140Bとを備えている。基板の昇降はモータの回転運動を直接直線運動に変換する方式が望ましい。その理由は、間に他の変換機構を入れると、その分、がたつく要素が増えることと、基板と測定部分の相対的移動プロファイルの設定が困難になるからである。すなわち、モータ140Aの回転運動を直接直線運動に変換することにより、複雑な動作なしで円板状基板200の移動とレーザのスキャンエリアの移動のプロファイルを決定できる。なお、円板状基板200を昇降させて、レーザのスキャンエリアを通過させる方法以外に、円板状基板200を固定してレーザのスキャンエリアをレーザごと昇降させる方法や、円盤状基板200とレーザのスキャンエリアの双方を動かす方法もある。   In FIG. 2, the elevating unit 140 includes a motor 140A and a conversion mechanism 140B that converts the rotational motion of the motor 140A into a linear motion. As for the raising and lowering of the substrate, a method of directly converting the rotational motion of the motor into linear motion is desirable. The reason for this is that if another conversion mechanism is inserted in between, the number of elements that play is increased and the setting of the relative movement profile between the substrate and the measurement portion becomes difficult. That is, by directly converting the rotational motion of the motor 140A into a linear motion, it is possible to determine the profile of the movement of the disk-shaped substrate 200 and the movement of the laser scan area without complicated operations. In addition to the method of raising and lowering the disk-shaped substrate 200 and passing it through the laser scan area, a method of fixing the disk-shaped substrate 200 and raising and lowering the laser scan area together with the laser, the disk-shaped substrate 200 and the laser There is also a way to move both scan areas.

このように昇降部140をモータ140Aと変換機構140Bで構成することで、振動を発生する要素を最小限に抑えることができ、振動による測定のバラツキを低く抑えることが可能となる。なお、回転運動を直線運動に変換する変換機構として、ボールネジが知られている。また、モータ140Aとしては、サーボモータ又はリニアモータが好適である。これらのモータを使用することで振動を低く抑えることができる。また、これらのモータは速度の変更が容易で、かつ安定した駆動が可能となる。例えば、基板受け取り時は早めの速度とし、測定時は遅めにするような使い方ができる。   In this way, by configuring the elevating unit 140 with the motor 140A and the conversion mechanism 140B, it is possible to minimize the elements that generate vibrations, and to suppress variations in measurement due to vibrations. Note that a ball screw is known as a conversion mechanism that converts rotational motion into linear motion. Moreover, as the motor 140A, a servo motor or a linear motor is suitable. By using these motors, vibration can be kept low. In addition, these motors can be easily changed in speed and can be driven stably. For example, it is possible to use a faster speed when receiving a substrate and a slower speed when measuring.

また、昇降部140は、可動する複数のパーツを有しており、パーツ間の結合にはネジが用いられている。この結合部分にはゴムなどの弾性部材を用いたブッシュ(図示略)が設けられており、このブッシュにより各パーツの振動を抑えるようにしている。   Moreover, the raising / lowering part 140 has a several movable part, and the screw is used for the coupling | bonding between parts. A bush (not shown) using an elastic member such as rubber is provided at the coupling portion, and the vibration of each part is suppressed by this bush.

基板と測定部分の相対的な移動プロファイルは、上記のような構成の装置であれば指定することが可能であり、円板状基板200が昇降時の一定速度のとき、あるいは加速度がかかっているときに測定することができる。円板状基板200を移動させる速度を遅くすることで振動の影響を極小化できるが、量産のタクトタイムを満たすことができない。一方、速くし過ぎると、装置の振動、空気抵抗によるブレが生じるのみならず、円板状基板200と基板ホルダ130が接触するときの衝撃による円板状基板200へのダメージが無視できなくなるため、上限速度は衝撃による基板ダメージが生じない値となり、円板状基板200と爪部130aの材質に依存する。   The relative movement profile of the substrate and the measurement part can be specified as long as the apparatus has the above-described configuration. When the disk-shaped substrate 200 is at a constant speed during elevation or acceleration, the acceleration is applied. Sometimes it can be measured. Although the influence of vibration can be minimized by slowing down the speed at which the disk-shaped substrate 200 is moved, the tact time for mass production cannot be satisfied. On the other hand, if the speed is too fast, not only vibration due to vibration of the apparatus and air resistance will occur, but also damage to the disk-shaped substrate 200 due to impact when the disk-shaped substrate 200 and the substrate holder 130 come into contact cannot be ignored. The upper limit speed is a value that does not cause substrate damage due to impact, and depends on the material of the disc-like substrate 200 and the claw portion 130a.

なお、円板状基板200がディスクケース160を出てからの振動対策を、円板状基板200が円板状基板200を保持するパーツから落下しない程度でとどめ、円板状基板200を測定位置に移動させた後にレーザセンサ120を動かしてもよい。このようにすると装置のコストは上昇するが、基板振動が小さくなり測定精度は向上する。   It should be noted that vibration countermeasures after the disk-shaped substrate 200 exits the disk case 160 are limited to the extent that the disk-shaped substrate 200 does not drop from the parts holding the disk-shaped substrate 200, and the disk-shaped substrate 200 is measured. The laser sensor 120 may be moved after being moved to. This increases the cost of the apparatus, but reduces the substrate vibration and improves the measurement accuracy.

また、本実施の形態では、円板状基板200を3個の爪部130a〜130cで下から支えるだけのものであったが、上方から押さえるようにしてもよい。具体的には、チャンファ形状と平行な開き角度を持つ爪部を円板状基板200の上方に設置し、昇降部140が昇降する際に、円板状基板200と接触し、円板状基板200の傾きを抑制する。これにより、上下から挟むことによる円板状基板200の固定が達成でき、振動の抑制と円板状基板200の姿勢の決定が可能となる。因みに、精度を重視して、精密に測定する場合、姿勢制御が可能となる爪部は大きな役割を持つが、円板状基板200の「内径測定」時よりも「板厚測定」時の方が測定値の安定化に寄与する。   Further, in the present embodiment, the disk-shaped substrate 200 is only supported from below by the three claw portions 130a to 130c, but may be pressed from above. Specifically, a claw portion having an opening angle parallel to the chamfer shape is installed above the disc-shaped substrate 200, and contacts the disc-shaped substrate 200 when the elevating unit 140 moves up and down. The inclination of 200 is suppressed. Thereby, fixation of the disk-shaped board | substrate 200 by pinching from the upper and lower sides can be achieved, and suppression of vibration and determination of the attitude | position of the disk-shaped board | substrate 200 are attained. Incidentally, the claw part that can control the posture plays a big role in the case of precise measurement with an emphasis on accuracy, but it is more in the “plate thickness measurement” than the “inner diameter measurement” of the disc-shaped substrate 200. Contributes to the stabilization of the measured value.

次に、図5に示すフローチャートを参照して、円板状基板内径測定装置100を用いた内径測定方法を説明する。まずラインレーザ112を照射する(S300)。次いで、基板ホルダ130によって円板状基板200を支持する(S310)。円板状基板200を支持した後、ラインレーザ112が円板状基板200の円孔210を通過するように基板ホルダ130を昇降させるとともに、昇降中、円板状基板200を反射または通過したラインレーザ112を受光し、その光量分布を取得する(S320)。次いで、取得した光量分布から、円板状基板200の円孔210の弦の長さを取得し、最大の弦の長さを円孔210の内径とする内径測定を行う(S330)。円板状基板200の内径を測定した後、測定した内径の値に応じて良品または不良品のいずれかの判断を行う品質検査を行う(S340)。このとき、良品または不良品の判断を行うためのID公差として±10umを用いた。そして、良品と判断したものは後続の工程に送り(S350)、不良品と判断したものは廃棄する(S360)。   Next, an inner diameter measuring method using the disk-shaped substrate inner diameter measuring apparatus 100 will be described with reference to the flowchart shown in FIG. First, the line laser 112 is irradiated (S300). Next, the disk-shaped substrate 200 is supported by the substrate holder 130 (S310). After supporting the disk-shaped substrate 200, the substrate holder 130 is moved up and down so that the line laser 112 passes through the circular hole 210 of the disk-shaped substrate 200, and the line reflected or passed through the disk-shaped substrate 200 during the lifting and lowering. The laser 112 is received and the light quantity distribution is acquired (S320). Next, the chord length of the circular hole 210 of the disc-shaped substrate 200 is obtained from the acquired light quantity distribution, and the inner diameter measurement is performed with the maximum chord length as the inner diameter of the circular hole 210 (S330). After measuring the inner diameter of the disc-shaped substrate 200, a quality inspection is performed to determine whether the product is a good product or a defective product according to the value of the measured inner diameter (S340). At this time, ± 10 μm was used as an ID tolerance for determining whether the product is good or defective. Then, if it is determined to be a non-defective product, it is sent to the subsequent process (S350), and if it is determined to be defective, it is discarded (S360).

以上のように、本発明の円板状基板内径測定装置100は、装置の振動対策がなされていることから、測定時のばらつきを半減することができ、社内規格の緩和、あるいは顧客要求規格の厳格化に対応することができる。   As described above, the disk-shaped substrate inner diameter measuring apparatus 100 according to the present invention has a countermeasure against vibration of the apparatus, and thus can reduce the variation at the time of measurement by half. It can cope with strictness.

同時に振動対策がなされることにより、円板状基板200を支持するアームの長さをより長くすることで、円板状基板200が通過する領域を広げることも可能になる。広がった領域に別のセンサを設けることにより、一つの機能のみでなく、複数の機能を持つことが可能となる。具体的には、ディスクケース160から取り出した直後に円板状基板200の内径を測定し、その上に円板状基板200の板厚を測定するセンサを設けると、アームが長くなることによる振動の悪影響を受け難くなる。また、板厚センサの代わりに、基板の透過率、反射率を検出するセンサを設けることでガラスの種類、材質を判断することもできる。また、温度センサを置いた場合、基板測定時の温度を保証することができ、基板の寸法と温度を同時に保証することができる。今後、測定部分の小さなセンサが世の中に出回れば、数多くの測定部分を搭載することが可能となり、小さいフットプリントで数多くの品質保証項目の測定と適合/不適合の判断ができるようになる。今回の発明では、基本的にセンサを固定しているが、センサが基板並び方向に動作できる機構をつけることにより測定速度の向上を図ることができる。   By taking measures against vibration at the same time, it is possible to increase the length of the arm that supports the disk-shaped substrate 200, thereby expanding the region through which the disk-shaped substrate 200 passes. By providing another sensor in the expanded area, it is possible to have not only one function but also a plurality of functions. Specifically, when a sensor for measuring the inner diameter of the disc-shaped substrate 200 is provided immediately after removal from the disk case 160 and the thickness of the disc-shaped substrate 200 is provided thereon, vibration due to the length of the arm becomes longer. It becomes difficult to be adversely affected by. Moreover, the kind and material of glass can also be judged by providing the sensor which detects the transmittance | permeability of a board | substrate, and a reflectance instead of a plate | board thickness sensor. When a temperature sensor is placed, the temperature at the time of substrate measurement can be guaranteed, and the size and temperature of the substrate can be guaranteed at the same time. In the future, if a sensor with a small measurement part becomes available in the world, it will be possible to mount a large number of measurement parts, and it will be possible to measure many quality assurance items and judge conformity / nonconformity with a small footprint. In the present invention, the sensor is basically fixed, but it is possible to improve the measurement speed by adding a mechanism that allows the sensor to operate in the direction in which the substrates are arranged.

なお、ラインレーザ112の照射範囲を変えることで、円板状基板200の外径も測定することができる。即ち、ライン光源110は、ラインレーザ112を円板状基板200の主表面を照射するように照射範囲を変更し、昇降部140は、ラインレーザ112が円板状基板200の主表面を超える範囲で基板ホルダ130を昇降させ、レーザセンサ(受光部)120は、円板状基板200の昇降中、円板状基板200を反射又は通過したラインレーザ112を受光し、その光量分布を取得し、内径測定部(測定部)150は、レーザセンサ120が取得した光量分布から、円板状基板200の直径の長さを取得し、それを外径とする。   Note that the outer diameter of the disk-shaped substrate 200 can also be measured by changing the irradiation range of the line laser 112. That is, the line light source 110 changes the irradiation range so that the line laser 112 is irradiated on the main surface of the disk-shaped substrate 200, and the lifting unit 140 is a range where the line laser 112 exceeds the main surface of the disk-shaped substrate 200. The substrate holder 130 is moved up and down, and the laser sensor (light receiving unit) 120 receives the line laser 112 reflected or passed through the disk-shaped substrate 200 while the disk-shaped substrate 200 is moved up and down, and acquires the light amount distribution. The inner diameter measuring unit (measuring unit) 150 acquires the length of the diameter of the disk-shaped substrate 200 from the light amount distribution acquired by the laser sensor 120 and sets it as the outer diameter.

また、測定方法を変更することで、円板状基板200の厚さも測定することができる。即ち、ライン光源110から円板状基板200にラインレーザ112を照射し、基板ホルダ130で円板状基板200を支持し、昇降部140でラインレーザ112が円板状基板200に照射されるように基板ホルダ130を昇降させ、円板状基板200の昇降中、レーザセンサ(受光部)120で、円板状基板200の表面及び裏面からの反射光を受光し、内径測定部(測定部)150で、円板状基板200の表面及び裏面からの反射光の干渉状態を計測することで円板状基板200の厚さを測定する。   Moreover, the thickness of the disk-shaped board | substrate 200 can also be measured by changing a measuring method. That is, the line laser 112 is irradiated from the line light source 110 to the disk substrate 200, the disk substrate 200 is supported by the substrate holder 130, and the line laser 112 is irradiated to the disk substrate 200 by the elevating unit 140. The substrate holder 130 is moved up and down, and while the disk-shaped substrate 200 is moved up and down, the laser sensor (light receiving unit) 120 receives the reflected light from the front and back surfaces of the disk-shaped substrate 200, and the inner diameter measuring unit (measurement unit). At 150, the thickness of the disk-shaped substrate 200 is measured by measuring the interference state of the reflected light from the front and back surfaces of the disk-shaped substrate 200.

次に、本発明の効果を明確にするために行った実施例について説明する。
(実施例)
本実施例においては、以下の工程を経て、磁気ディスク用ガラス基板および磁気ディスクを製造した。
Next, examples performed for clarifying the effects of the present invention will be described.
(Example)
In this example, a glass substrate for magnetic disk and a magnetic disk were manufactured through the following steps.

(1)形状加工工程及び第1ラッピング工程
まず、溶融させたアルミノシリケートガラスを上型、下型、胴型を用いたダイレクトプレスによりディスク形状に成型し、アモルファスの板状ガラスを得た。なお、アルミノシリケートガラスとしては、化学強化用のガラスを使用した。ダイレクトプレス以外に、フュージョン法、ダウンドロー法、またはフロート法で形成したシートガラスから研削砥石で切り出して円板状の磁気ディスク用ガラス基板を得てもよい。また、上記ガラスとしてアルミノシリケートガラス以外にもソーダライムガラス等を用いることもできる。
(1) Shape processing step and first lapping step First, the melted aluminosilicate glass was molded into a disk shape by direct pressing using an upper die, a lower die, and a barrel die to obtain an amorphous plate glass. In addition, the glass for chemical strengthening was used as aluminosilicate glass. In addition to direct pressing, a disk-shaped glass substrate for a magnetic disk may be obtained by cutting with a grinding wheel from sheet glass formed by a fusion method, a downdraw method, or a float method. In addition to aluminosilicate glass, soda lime glass can be used as the glass.

次に、この板状ガラスの両主表面をラッピング加工し、ディスク状のガラス母材とした。このラッピング加工は、遊星歯車機構を利用した両面ラッピング装置により、アルミナ系遊離砥粒を用いて行った。具体的には、板状ガラスの両面に上下からラップ定盤を押圧させ、遊離砥粒を含む研削液を板状ガラスの主表面上に供給し、これらを相対的に移動させてラッピング加工を行った。このラッピング加工により、平坦な主表面を有するガラス母材を得た。   Next, both main surfaces of the plate glass were lapped to form a disk-shaped glass base material. This lapping process was performed using alumina free abrasive grains with a double-sided lapping apparatus using a planetary gear mechanism. Specifically, the lapping platen is pressed on both sides of the plate glass from above and below, the grinding liquid containing free abrasive grains is supplied onto the main surface of the plate glass, and these are moved relative to each other for lapping. went. By this lapping process, a glass base material having a flat main surface was obtained.

(2)切り出し工程(コアリング、フォーミング)
次に、ダイヤモンドカッタを用いてガラス母材を切断し、このガラス母材から、円板状のガラス基板を切り出した。次に、円筒状のダイヤモンドドリルを用いて、このガラス基板の中心部に円孔を形成し、ドーナツ状のガラス基板とした(コアリング)。そして内周端面および外周端面をダイヤモンド砥石によって研削し、所定の面取り加工を施した(フォーミング)。
(2) Cutting process (coring, forming)
Next, the glass base material was cut using a diamond cutter, and a disk-shaped glass substrate was cut out from the glass base material. Next, using a cylindrical diamond drill, a circular hole was formed in the center of the glass substrate to obtain a donut-shaped glass substrate (coring). Then, the inner peripheral end face and the outer peripheral end face were ground with a diamond grindstone and subjected to predetermined chamfering (forming).

(3)第2ラッピング工程
次に、得られたガラス基板の両主表面について、第1ラッピング工程と同様に、第2ラッピング加工を行った。この第2ラッピング工程を行うことにより、前工程である切り出し工程や端面研磨工程において主表面に形成された微細な凹凸形状を予め除去しておくことができ、後続の主表面に対する研磨工程を短時間で完了させることができるようになる。
(3) Second Lapping Step Next, a second lapping process was performed on both main surfaces of the obtained glass substrate in the same manner as in the first lapping step. By performing this second lapping step, it is possible to remove in advance the fine unevenness formed on the main surface in the cutting step and end surface polishing step, which are the previous steps, and shorten the subsequent polishing step on the main surface. Will be able to be completed in time.

(4)端面研磨工程
次に、ガラス基板の端面について、ブラシ研磨方法により、鏡面研磨を行った。このとき、研磨砥粒としては、酸化セリウム砥粒を含むスラリ(遊離砥粒)を用いた。この端面研磨工程により、ガラス基板の端面は、パーティクル等の発塵を防止できる鏡面状態に加工された。
(4) End surface polishing process Next, the end surface of the glass substrate was mirror-polished by a brush polishing method. At this time, slurry (free abrasive grains) containing cerium oxide abrasive grains was used as the abrasive grains. By this end surface polishing step, the end surface of the glass substrate was processed into a mirror surface state capable of preventing generation of particles and the like.

(5)主表面研磨工程(第1研磨工程)
主表面研磨工程として、まず第1研磨工程を施した。この第1研磨工程は、前述のラッピング工程において主表面に残留したキズや歪みの除去を主たる目的とするものである。この第1研磨工程においては、遊星歯車機構を有する両面研磨装置により、硬質樹脂ポリッシャを用いて、主表面の研磨を行った。研磨液としては、酸化セリウム砥粒を用いた。
(5) Main surface polishing step (first polishing step)
As a main surface polishing step, first, a first polishing step was performed. The first polishing process is mainly intended to remove scratches and distortions remaining on the main surface in the lapping process described above. In the first polishing step, the main surface was polished using a hard resin polisher by a double-side polishing apparatus having a planetary gear mechanism. As the polishing liquid, cerium oxide abrasive grains were used.

(6)化学強化工程
次に、前述のラッピング工程及び研磨工程を終えたガラス基板に、化学強化を施した。化学強化処理を行うことにより、磁気ディスク基板の表層部に高い圧縮応力を生じさせることができ、耐衝撃性を向上させることができる。
(6) Chemical strengthening process Next, the glass substrate which finished the above-mentioned lapping process and grinding | polishing process was chemically strengthened. By performing the chemical strengthening treatment, a high compressive stress can be generated in the surface layer portion of the magnetic disk substrate, and the impact resistance can be improved.

(7)主表面研磨工程(第1研磨工程)
次に、主表面研磨工程として、第2研磨工程を施した。この第2研磨工程は、主表面を鏡面状に仕上げることを目的とする。この第2研磨工程においては、遊星歯車機構を有する両面研磨装置により、軟質発泡樹脂ポリッシャを用いて、主表面の鏡面研磨を行った。研磨液としては、第1研磨工程で用いた酸化セリウム砥粒よりも微細な酸化セリウム砥粒を用いた。
(7) Main surface polishing step (first polishing step)
Next, a second polishing step was performed as the main surface polishing step. The purpose of this second polishing step is to finish the main surface into a mirror surface. In the second polishing step, mirror polishing of the main surface was performed using a soft foamed resin polisher by a double-side polishing apparatus having a planetary gear mechanism. As the polishing liquid, cerium oxide abrasive grains finer than the cerium oxide abrasive grains used in the first polishing step were used.

(8)精密洗浄工程
次に、化学強化処理が施されたガラス基板の精密洗浄を行った。これはヘッドクラッシュやサーマルアスペリティ障害の原因となる研磨剤残渣や外来の鉄系コンタミなどを除去し、表面が平滑で清浄なガラス基板を得るためのものである。精密洗浄工程としては、アルカリ性水溶液による洗浄の後に、水リンス洗浄、IPA洗浄工程を行った。
(8) Precision cleaning process Next, the glass substrate to which the chemical strengthening process was performed was precisely cleaned. This is to remove abrasive residues and foreign iron-based contaminants that cause head crush and thermal asperity failure, and to obtain a glass substrate with a smooth surface and a clean surface. As a precision cleaning process, a water rinse cleaning and an IPA cleaning process were performed after cleaning with an alkaline aqueous solution.

(9)内径測定工程
上記(8)の精密洗浄工程までで完成されたガラス基板に対して、前述した円板状基板内径測定装置100を適用し、以下の工程で内径を求めた。
ライン光照射工程:ラインレーザ112を円板状基板200であるガラス基板の主表面に照射する。
基板支持工程:基板ホルダ130によってガラス基板を支持する。
昇降工程:ラインレーザ112がガラス基板の円孔を通過するように基板ホルダ130を昇降させる。θ=10°とする。
受光工程:ガラス基板の昇降中、ガラス基板を反射又は通過したライン光を受光し、その光量分布を取得する。
測定工程:受光工程で取得した光量分布から、ガラス基板の円孔の弦の長さを取得し、最大の弦の長さを円孔の内径とする。
(9) Inner Diameter Measuring Step The above-described disk-shaped substrate inner diameter measuring apparatus 100 was applied to the glass substrate completed up to the precision cleaning step (8), and the inner diameter was determined in the following steps.
Line light irradiation step: The line laser 112 is irradiated to the main surface of the glass substrate which is the disc-shaped substrate 200.
Substrate support step: A glass substrate is supported by the substrate holder 130.
Elevating step: The substrate holder 130 is moved up and down so that the line laser 112 passes through the circular hole of the glass substrate. θ = 10 °.
Light receiving step: While the glass substrate is moved up and down, the line light reflected or passed through the glass substrate is received, and the light quantity distribution is acquired.
Measuring process: The length of the string of the circular hole of the glass substrate is acquired from the light quantity distribution acquired in the light receiving process, and the maximum string length is defined as the inner diameter of the circular hole.

(10)品質検査工程
上記(8)の内径測定工程を行った後、品質検査を行った。
品質検査工程:測定した内径の値に応じて良品または不良品のいずれかの判断を行う。良品または不良品の判断を行うためのID公差として±10umを用いた。
後続工程送致工程:良品と判断されたものは後続の工程に送る.
廃棄工程:不良品と判断されたものは廃棄する。
(10) Quality inspection process After performing the internal diameter measurement process of said (8), the quality inspection was performed.
Quality inspection process: Judges whether the product is good or defective according to the measured inner diameter value. ± 10 μm was used as an ID tolerance for determining whether the product is good or defective.
Subsequent process sending process: Products judged to be non-defective are sent to the subsequent process.
Disposal process: Dispose of defective products.

(11)磁気ディスク製造工程
上述した品質検査工程を経て良品と判断されたガラス基板の両面に、Cr合金からなる付着層、FeCoCrB合金からなる軟磁性層、Ruからなる下地層、CoCrPt−TiO2合金からなる垂直磁気記録層、水素化炭素からなる保護層、パーフルオロポリエーテルからなる潤滑層を順次成膜することにより、垂直磁気記録ディスクを製造した。なお、本構成は垂直磁気ディスクの構成の一例であるが、面内磁気ディスクとして磁性層等を構成してもよい。
(11) Magnetic disk manufacturing process An adhesive layer made of Cr alloy, a soft magnetic layer made of FeCoCrB alloy, an underlayer made of Ru, and a CoCrPt—TiO 2 alloy on both surfaces of a glass substrate that has been determined to be non-defective through the quality inspection process described above. A perpendicular magnetic recording disk was manufactured by sequentially forming a perpendicular magnetic recording layer made of, a protective layer made of hydrogenated carbon, and a lubricating layer made of perfluoropolyether. Although this configuration is an example of a configuration of a perpendicular magnetic disk, a magnetic layer or the like may be configured as an in-plane magnetic disk.

本発明は上記実施の形態に限定されず、適宜変更して実施することができる。上記実施の形態における材質、個数、サイズ、処理手順などは一例であり、本発明の効果を発揮する範囲内において種々変更して実施することが可能である。その他、本発明の目的の範囲を逸脱しない限りにおいて適宜変更して実施することが可能である。   The present invention is not limited to the above embodiment, and can be implemented with appropriate modifications. The material, the number, the size, the processing procedure, and the like in the above embodiment are merely examples, and various modifications can be made within the range where the effects of the present invention are exhibited. In addition, various modifications can be made without departing from the scope of the object of the present invention.

100 円板状基板内径測定装置
110 ラインレーザ光源
112 ラインレーザ
120 レーザセンサ
130 基板ホルダ
130a 爪部
140 昇降部
140A モータ
140B 変換機構
150 内径測定部
160 ディスクケース
200 円板状基板
210 円孔
220A〜220C 支点
DESCRIPTION OF SYMBOLS 100 Disk-shaped board | substrate inner diameter measuring apparatus 110 Line laser light source 112 Line laser 120 Laser sensor 130 Substrate holder 130a Claw part 140 Lifting part 140A Motor 140B Conversion mechanism 150 Inner diameter measurement part 160 Disc case 200 Disc-shaped board 210 Circular hole 220A-220C fulcrum

Claims (7)

中央に円孔が形成された円板状基板の内径を測定する円板状基板内径測定装置であって、
ライン光を前記円板状基板の前記円孔及びその周囲に照射するライン光源と、前記円板状基板を支持する基板ホルダと、前記ライン光が前記円板状基板の前記円孔を通過するように前記基板ホルダを昇降させる昇降部と、前記円板状基板の昇降中、前記円板状基板を反射又は通過したライン光を受光し、その光量分布を取得する受光部と、前記受光部が取得した光量分布から、前記円板状基板の円孔の弦の長さを取得し、最大の弦の長さを円孔の内径とする測定部と、を具備し、
前記円板状基板を支持した基板ホルダは、該測定装置の接地面に対する鉛直線に対して0°を超え10°以下傾けた状態で昇降させることを特徴とする円板状基板内径測定装置。
A disk-shaped substrate inner diameter measuring device for measuring the inner diameter of a disk-shaped substrate having a circular hole formed in the center,
A line light source that irradiates the circular hole of the disk-shaped substrate and the periphery thereof with line light, a substrate holder that supports the disk-shaped substrate, and the line light passes through the circular hole of the disk-shaped substrate. The elevating unit for elevating and lowering the substrate holder, the light receiving unit for receiving the line light reflected or passed through the disk-shaped substrate during the elevating of the disk-shaped substrate, and acquiring the light quantity distribution, and the light receiving unit From the obtained light amount distribution, the length of the string of the circular hole of the disk-shaped substrate is obtained, and a measuring unit having the maximum chord length as the inner diameter of the circular hole,
The disk-shaped substrate inner diameter measuring apparatus, wherein the substrate holder that supports the disk-shaped substrate is lifted and lowered in a state of being tilted by more than 0 ° and not more than 10 ° with respect to a vertical line with respect to the ground plane of the measuring device.
前記昇降部は、モータと、該モータの回転運動を直線運動に変換する変換機構とを具備し、前記モータは、サーボモータ又はリニアモータであることを特徴とする請求項1に記載の円板状基板内径測定装置。   2. The disk according to claim 1, wherein the elevating unit includes a motor and a conversion mechanism that converts a rotational motion of the motor into a linear motion, and the motor is a servo motor or a linear motor. Substrate inner diameter measuring device. 前記昇降部を構成する各種パーツの結合部分に弾性部材を用いたブッシュを設けたことを特徴とする請求項2に記載の円板状基板内径測定装置。   3. The disk-shaped substrate inner diameter measuring apparatus according to claim 2, wherein a bush using an elastic member is provided at a joint part of various parts constituting the elevating part. 中央に円孔が形成された円板状基板の厚さを測定する円板状基板厚さ測定装置であって、ライン光を前記基板に照射するライン光源と、前記基板を支持する基板ホルダと、前記ライン光が前記基板に照射されるように前記基板ホルダを昇降させる昇降部と、前記基板の昇降中、前記基板の表面及び裏面からの反射光を受光する受光部と、前記基板の表面及び裏面からの反射光の干渉状態を計測することで前記基板の厚さを測定する測定部と、を具備することを特徴とする円板状基板厚さ測定装置。   A disk-shaped substrate thickness measuring device for measuring the thickness of a disk-shaped substrate having a circular hole formed in the center, a line light source for irradiating the substrate with line light, a substrate holder for supporting the substrate, An elevating unit that elevates and lowers the substrate holder so that the line light is applied to the substrate; a light receiving unit that receives reflected light from the front and back surfaces of the substrate during elevating the substrate; and a surface of the substrate And a measuring unit that measures the thickness of the substrate by measuring the interference state of reflected light from the back surface. 中央に円孔が形成された円板状基板の寸法を測定する円板状基板内径測定方法であって、ライン光を前記円板状基板の主表面に照射するライン光照射工程と、基板ホルダによって前記円板状基板を支持する基板支持工程と、前記ライン光が前記円板状基板の前記円孔を通過するように前記基板ホルダを昇降させる昇降工程と、前記円板状基板の昇降中、前記円板状基板を反射又は通過したライン光を受光し、その光量分布を取得する受光工程と、前記受光工程で取得した光量分布から、前記円板状基板の円孔の弦の長さを取得し、最大の弦の長さを円孔の内径とする測定工程と、を具備し、前記円板状基板を支持した基板ホルダは、該測定装置の接地面に対する鉛直線に対して0°を超え10°以下傾けた状態で昇降させることを特徴とする円板状基板内径測定方法。   A disk-shaped substrate inner diameter measuring method for measuring a dimension of a disk-shaped substrate having a circular hole formed in the center, the line light irradiation step for irradiating the main surface of the disk-shaped substrate with line light, and a substrate holder A substrate supporting step for supporting the disk-shaped substrate, a lifting step for lifting and lowering the substrate holder so that the line light passes through the circular hole of the disk-shaped substrate, and during the lifting and lowering of the disk-shaped substrate A light-receiving step of receiving line light reflected or passed through the disk-shaped substrate and acquiring the light amount distribution; and a length of a chord of a circular hole of the disk-shaped substrate from the light amount distribution acquired in the light-receiving step And a measurement step in which the maximum chord length is the inner diameter of the circular hole, and the substrate holder that supports the disk-shaped substrate is 0 with respect to a vertical line with respect to the ground plane of the measurement device. A circle characterized by being raised and lowered in an inclined state exceeding 10 ° and not more than 10 ° Method for measuring the inner diameter of a plate substrate. 請求項5に記載の円板状基板内径測定方法を用いて円板状基板の内径を測定する内径測定工程と、前記測定した内径の値に応じて良品又は不良品のいずれかの判断を行う品質検査工程とを具備することを特徴とする円板状基板の製造方法。   An inner diameter measuring step for measuring the inner diameter of the disk-shaped substrate using the disk-shaped substrate inner diameter measuring method according to claim 5, and determining whether the product is non-defective or defective according to the value of the measured inner diameter. And a quality inspection step. A method of manufacturing a disk-shaped substrate. 請求項6に記載の円板状基板の製造方法を用いて製造した円板状基板に少なくとも磁性層を形成することを特徴とする磁気ディスク製造方法。   A magnetic disk manufacturing method comprising forming at least a magnetic layer on a disk-shaped substrate manufactured using the method for manufacturing a disk-shaped substrate according to claim 6.
JP2010198511A 2010-09-06 2010-09-06 Disk-like substrate inner diameter measuring instrument, disk-like substrate inner diameter measuring method and method for manufacturing disk-like substrate Pending JP2012059307A (en)

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2014052257A (en) * 2012-09-06 2014-03-20 Asahi Glass Co Ltd Device for measuring shape of disk-shaped substrate and method thereof
CN104457597A (en) * 2014-11-26 2015-03-25 福建省万达汽车玻璃工业有限公司 Detection method and detection device for hole diameter and hole site of glass
CN110345898A (en) * 2019-08-14 2019-10-18 大连凯晟科技发展有限公司 A kind of pressure vessel inner diameter measuring device

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2014052257A (en) * 2012-09-06 2014-03-20 Asahi Glass Co Ltd Device for measuring shape of disk-shaped substrate and method thereof
CN103673919A (en) * 2012-09-06 2014-03-26 旭硝子株式会社 Shape measurement device of disk-like substrate, and method thereof
CN104457597A (en) * 2014-11-26 2015-03-25 福建省万达汽车玻璃工业有限公司 Detection method and detection device for hole diameter and hole site of glass
CN110345898A (en) * 2019-08-14 2019-10-18 大连凯晟科技发展有限公司 A kind of pressure vessel inner diameter measuring device

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