JPH01148904A - Apparatus for inspecting magnetic disk - Google Patents
Apparatus for inspecting magnetic diskInfo
- Publication number
- JPH01148904A JPH01148904A JP30751487A JP30751487A JPH01148904A JP H01148904 A JPH01148904 A JP H01148904A JP 30751487 A JP30751487 A JP 30751487A JP 30751487 A JP30751487 A JP 30751487A JP H01148904 A JPH01148904 A JP H01148904A
- Authority
- JP
- Japan
- Prior art keywords
- disk
- displacement
- measured
- magnetic disk
- microcomputer
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000006073 displacement reaction Methods 0.000 claims abstract description 57
- 238000005259 measurement Methods 0.000 claims abstract description 25
- 238000007689 inspection Methods 0.000 claims 1
- 239000000758 substrate Substances 0.000 claims 1
- 238000000034 method Methods 0.000 description 11
- 238000012937 correction Methods 0.000 description 5
- 238000010586 diagram Methods 0.000 description 5
- 238000006243 chemical reaction Methods 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 238000013459 approach Methods 0.000 description 2
- 238000011161 development Methods 0.000 description 2
- 238000012423 maintenance Methods 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- 230000006866 deterioration Effects 0.000 description 1
- 239000000428 dust Substances 0.000 description 1
- 238000000691 measurement method Methods 0.000 description 1
- 238000011326 mechanical measurement Methods 0.000 description 1
- 238000005096 rolling process Methods 0.000 description 1
- 239000010409 thin film Substances 0.000 description 1
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は、磁気ディスク開発または製造時の形状測定に
係り、特に薄膜磁気ディスクの様な、高性能円板で、厳
しい形状仕様を持つものの製造または開発ライン上での
円板評価に好適な装置に関する。[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to shape measurement during the development or manufacturing of magnetic disks, particularly for high-performance disks such as thin-film magnetic disks that have strict shape specifications. The present invention relates to a device suitable for evaluating disks on a manufacturing or development line.
磁気ディスクの表面のうねり、反りは、従来より、静電
容量型の変位計を使用し、あるトラックで測定を行ない
そのトラックで検出されたうねりの最大ピークと最小谷
部の値をランナウトと称して把握していた。この測定方
法については、例えハ、エイΦエヌ・ニス拳アイ規格、
エックス３ビー７７１ｑ８１−５７第５頁において論じ
られている。Waviness and warpage on the surface of a magnetic disk have traditionally been measured using a capacitive displacement meter on a certain track, and the values of the maximum peak and minimum trough of the waviness detected on that track are called runout. I understood that. For this measurement method, for example,
Discussed on page 5 of X3B 771q81-57.
また、この種の静電容量型変位計を使用したディスクの
うねり測定に於いて、軸の振れによる誤差な相殺する工
夫を行ったものとして、特開昭５７−２１１５０３号が
知られている。Furthermore, Japanese Patent Laid-Open No. 57-211503 is known as a technique for canceling out errors caused by shaft vibration in measuring disk waviness using this type of capacitive displacement meter.
〔発明が解決しよ５とする問題点〕
上記従来技術では、測定電極をディスクの回転半径方向
に移動しながら測定を行なう争が考慮されて居もず、測
定電極の移動機構が員備されていない。従って、測定′
電極を半径方向にずらしながら、ディスク表面全面のう
ねりの形状を測定する事ができない。また、この装置で
、一般的な移動機構を組合せて、測定電極を別の半径位
置へ移動しても、ディスクの絶対的な形状を測定するに
は、回転軸に対して完全に直角な一直線上を移動しなけ
ればならないため、その様な送りステージは、寸法的に
大きく位置決め、軸合せの難しい機構となる。また、回
転軸のもみすり運動による円板の振れは、測定半径によ
って異なるため、一定半径位置の変位を基準として測定
電極の変位測定値との差を求める本−ｆｃｆＬには、測
定電極と基準電極が離れるに従い、誤差が増加するとい
う問題があったＯ
〔問題点を解決するための手段〕
上記問題点は、測定電極の移動機ｍな追加するφ及び、
測定電極の送り時の振れと回転軸のもみすり運動による
ディスクの振れｌｔ慣出するための、参照ディスクな被
測定ディスクと同一の回転軸に取付ける事により解決さ
れる。この参照ディスクは、あらかじめ別の方法で、高
精度に反シ量を測定しておいたものを使用し、測定電極
で測定された変位量から同時、または漁次に基準電極で
測定された変位ｔをさし引いた変位量がマイクロコンビ
エータにとり込まれた後に、さらにこの参照ディスクの
反り量を補正して、被測定ディスクの高精度な真の反り
量を算出する。[Problems to be Solved by the Invention] The above-mentioned prior art does not take into consideration the issue of performing measurements while moving the measuring electrode in the direction of the rotation radius of the disk, and does not include a mechanism for moving the measuring electrode. Not yet. Therefore, the measurement′
It is not possible to measure the shape of the undulations on the entire disk surface while shifting the electrode in the radial direction. In addition, even if this device is combined with a general movement mechanism to move the measurement electrode to another radial position, it is still necessary to move the measuring electrode in a completely perpendicular direction to the rotation axis in order to measure the absolute shape of the disk. Since such a feed stage must be moved along a line, it is a dimensionally large mechanism that is difficult to position and align. In addition, since the run-out of the disk due to the rubbing motion of the rotating shaft differs depending on the measurement radius, this book-fcfL, which calculates the difference between the displacement measurement value of the measurement electrode based on the displacement at a constant radial position, includes the measurement electrode and reference There is a problem that the error increases as the electrodes move away. [Means for solving the problem] The above problem is caused by the addition of φ and
This problem can be solved by attaching the reference disk to the same rotating shaft as the disk to be measured, in order to get used to the deflection of the disk due to the shaking during feeding of the measuring electrode and the rubbing motion of the rotating shaft. This reference disk is used to measure the amount of displacement with high precision using another method in advance, and the displacement measured with the reference electrode is calculated from the amount of displacement measured with the measurement electrode at the same time or after the measurement. After the amount of displacement obtained by subtracting t is taken into the micro combinator, the amount of warpage of this reference disk is further corrected to calculate a highly accurate true amount of warpage of the disk to be measured.
〔作用Ｊ 本発明の原理を第１図に従って詳細に述べる。[Action J The principle of the present invention will be described in detail with reference to FIG.
被測定ディスクと参照ディスクは、センタハブ４に互の
取付面が平行になる様に取り付けられており、モータ８
によって回転される。但し、軸受、架台等説明に不要な
ものは省略する。各ディスク表面の変位は、測定変位セ
ンサ２′と参照変位センサ１１によって各々測定される
。これら２つのセンサは、移動台１０と一体で２つのセ
ンサが相対的に動かないように固定されておシ、この移
動台は移動台送り機構１１によってディスクの半径方向
に移動する。これらのセンナの出力は、変位電圧変換回
路６１によって変位に対応した電気信号に変換され、両
者の差、つまり真のディスク変位な差動ユニット５で求
め、マイクロコンビエータ１２に入力される。マイクロ
コンビエータは、移動台の現在位置とその位置での真の
ディスク変位を記憶し、出力装置に出力する。The disk to be measured and the reference disk are mounted on the center hub 4 so that their mounting surfaces are parallel to each other, and the motor 8
rotated by However, things unnecessary for the explanation, such as bearings and frames, are omitted. The displacement of each disk surface is measured by a measurement displacement sensor 2' and a reference displacement sensor 11, respectively. These two sensors are integrated with a moving table 10 and fixed so that the two sensors do not move relative to each other, and this moving table is moved in the radial direction of the disk by a moving table feeding mechanism 11. The outputs of these sensors are converted into electric signals corresponding to displacement by a displacement voltage conversion circuit 61, and the difference between the two, that is, the true disk displacement, is determined by the differential unit 5 and inputted to the micro combinator 12. The micro combinator stores the current position of the movable table and the true disk displacement at that position, and outputs it to the output device.
被測定ディスク変位センサ１′は、ディスクの回転軸１
４に対して直角な平面内を、回転軸に対して、高精度に
直線運動する必要がある。従って、移動台の移動時の振
れな頂カ低減し、回転軸に対して直角出しを行なう必要
がある。しかし、移動台は、しゆう動面またはころがり
面を持ち、この面の平面精度を充分に上げる事は難かし
く、更にこの面に付着した塵介により新たな振れが生じ
る等、精度の維持は困難である。また、回転軸との直角
出しも、特に高精度な測定が必要であり、装置組立上の
コスト高と保守性低下を招く。しかし、本発明では、移
動台のうね９や、回転軸に直角な平面に対する傾き、ま
たは回転軸のもみすり運動等が影響して生じたディスク
表面の変位測定誤差が、参照ディスクと参照変位センサ
の変位を差し引くことにより相殺されるために、単純な
機構で高精度の測定が可能となる。The measured disk displacement sensor 1' is connected to the rotation axis 1 of the disk.
It is necessary to move linearly with high accuracy in a plane perpendicular to the axis of rotation. Therefore, it is necessary to reduce the vibration and peak force when the movable base is moved, and to align the movable base at right angles to the rotation axis. However, the moving table has a sliding surface or a rolling surface, and it is difficult to sufficiently improve the flatness of this surface, and furthermore, dust adhering to this surface causes new runout, making it difficult to maintain accuracy. Have difficulty. Furthermore, setting the angle at right angles to the rotating shaft also requires particularly high-precision measurement, which leads to higher equipment assembly costs and lower maintainability. However, in the present invention, the displacement measurement error of the disk surface caused by the influence of the ridges 9 of the moving table, the inclination with respect to the plane perpendicular to the rotation axis, or the rubbing motion of the rotation axis, etc. Since this is offset by subtracting the displacement of the sensor, highly accurate measurement is possible with a simple mechanism.
本発明では、出力結果の処理にマイクロコンビエータ１
２Ｉｋ：使用している。これは、別の方法で測定した参
照ディスクの表面形状もとにして、上記の機構上の測定
誤差相殺後の変位測定値を補正するためと、半径方向に
移動台を移動させながら取り込んだ測定値により、ディ
スクの反り量を表示したり、反りによる合否判定を行う
ためである。In the present invention, the micro combinator 1 is used to process the output results.
2Ik: Used. This is done in order to correct the displacement measurement value after canceling out the mechanical measurement error mentioned above based on the surface shape of the reference disk measured by another method, and also to correct the displacement measurement value taken while moving the movable table in the radial direction. This is to display the amount of warpage of the disc and to make pass/fail judgments based on the warpage.
参照ディスクの反りが、必要とされる測定値よシも充分
に小さい場合には、この補正は不要である。If the warpage of the reference disk is sufficiently small compared to the required measurements, this correction is not necessary.
〔実施例〕
本発明の実施例を第１１図に従って説明する。参照変位
センサ１′と測定変位センサ２′には、静電容Ｊｉｍの
変位計？：使用し、参照ディスクには、直径２１２ ｒ
ｎｌｎ ％ ５ ｍｍ厚のアルミディスクを高精度に研
磨したものを使用し、移動台にはクロスローラー型の１
・前ステージを使用し、移動台送り機構にはステッピン
グモータとボールネジＪｋｙ！用した。[Example] An example of the present invention will be described with reference to FIG. The reference displacement sensor 1' and the measurement displacement sensor 2' include capacitance Jim displacement meters. : Use and reference disk has a diameter of 212 r
nln % A highly precisely polished aluminum disk with a thickness of 5 mm is used, and the moving table is equipped with a cross roller type 1
・Uses the front stage and uses a stepping motor and ball screw Jky for the moving table feed mechanism! used.
ディスクを３００Ｏｒｐｍ で回転させた時の変位電圧
変換ユニットの直後の出力波形を縦軸、ディスクの回転
角度を横軸に示したグラフを第３図に示す。縦軸は、電
圧を変位に書き直して示す。半径ＩＱＯｍｍでの測定を
行ない、測定変位センサからの測定変位電圧２１と参照
変位センサからの参照変位電圧２２と、測定変位電圧か
ら参照変位電圧を差し引いた後の参照変位補正後′電圧
２３を測定すると、参照電圧には、軸の傾きによる変位
波形が見られるが、参照変位補正後電圧からは、その成
分が除去されており、本発明の効果が確認された。FIG. 3 shows a graph in which the vertical axis is the output waveform immediately after the displacement voltage conversion unit when the disk is rotated at 300 rpm, and the horizontal axis is the rotation angle of the disk. The vertical axis shows voltage rewritten as displacement. Perform measurement at a radius of IQOmm, and measure the measured displacement voltage 21 from the measured displacement sensor, the reference displacement voltage 22 from the reference displacement sensor, and the reference displacement corrected voltage 23 after subtracting the reference displacement voltage from the measured displacement voltage. As a result, although a displacement waveform due to the inclination of the axis was seen in the reference voltage, that component was removed from the reference displacement-corrected voltage, confirming the effect of the present invention.
ディスク回転角ｏｆ！Ｌに注目し、移動台を半径方向に
動かして測定した測定変位電圧と参照変位補正後電圧と
を、変位量に換Ｋして縦軸とし、半径を横軸としてプロ
ットしたグラフを第４図に示す。Disc rotation angle of! Figure 4 is a graph in which the measured displacement voltage measured by moving the movable table in the radial direction and the reference displacement-corrected voltage, focusing on L, are converted into displacement amount K and plotted on the vertical axis and the radius as the horizontal axis. Shown below.
測定変位は、移動台の傾きにより、外周に向う程増大す
るが、参照変位電圧補正後２３は、傾きが補正されてい
る。また、参照ディスクを予め測定して得た形状で補正
すると、参照ディスク形状補正後２４が得られ、ディス
クの反り形状を高精度に示している。The measured displacement increases toward the outer periphery due to the inclination of the moving table, but after the reference displacement voltage correction 23, the inclination is corrected. Further, when the reference disk is corrected using the shape obtained by measuring it in advance, a corrected reference disk shape 24 is obtained, which shows the warped shape of the disk with high accuracy.
参照ディスクの形状補正は、ディスク表面を極座標で半
径方向に９分割、周方向に１００分割し、各分割点での
回転軸方向の反りｔを、最内周クランプ面の近以平面か
ら求め、マイクロコンビ３−タに入力しておき、参照電
位補正後電圧なＡＤ変換してマイクロコンピュータに取
り込んだデータを差し引くことにより行なった。この分
割数は、必要とされる測定精度に従って変更可能である
。To correct the shape of the reference disk, the disk surface is divided into 9 parts in the radial direction and 100 parts in the circumferential direction using polar coordinates, and the warp t in the rotational axis direction at each dividing point is determined from the nearest plane of the innermost circumferential clamping surface. This was done by subtracting the data that had been input into the microcomputer, had been AD-converted into a voltage after reference potential correction, and had been taken into the microcomputer. This number of divisions can be changed according to the required measurement accuracy.
また、半径方向にステップ移動でなく、連続的に移動し
ながららせん状に変位測定を行なった場合には、補正デ
ータの形式を変更し、同様の形状補正を行う。Further, when the displacement is measured in a spiral shape while moving continuously in the radial direction instead of by step movement, the format of the correction data is changed and similar shape correction is performed.
変位センサの取付方法には第１図の方式と第５図の如く
２枚のディスクの内側に２個置く方式と・これら以外に
、２枚のディスクの外側に２個置く方式、測定ディスク
の内側と参照ディスクの外側とに置く方式等の変更が可
能であり、その場合には第５図の様に差動ユニット５の
前段に極圧反転ユニット３０を配置するか、差動ユニッ
トの代りに加算ユニットを配置する。倒れの場合も、２
枚のディスクの取付面が平行を保って回転するため、回
転または移動台の移動により一方のセンサにディスクが
近付くと他方のセンサからもう一方のディスクが離れる
時には加算、一方のセンナにディスクが近付くと他方の
センサからディスクからもう一方のディスクが近付く時
には差動を行なう様ニ、差動ユニット、加算ユニット、
極性反転ユニ ４ツトを配置する。There are two ways to install displacement sensors: the method shown in Figure 1, the method of placing two sensors on the inside of two disks as shown in Figure 5, and the method of placing two sensors on the outside of two disks, and the method of placing two sensors on the outside of two disks as shown in Figure 5. It is possible to change the method of placing it on the inside and the outside of the reference disk. In that case, the extreme pressure reversing unit 30 may be placed in front of the differential unit 5 as shown in FIG. Place the addition unit in . In case of falling, 2
Since the mounting surfaces of the two disks rotate while keeping parallel, when the disk approaches one sensor due to rotation or movement of the moving table, the addition increases when the other disk moves away from the other sensor, and the disk approaches one sensor. A differential unit, an addition unit,
Place 4 polarity reversal units.
差動ユニット、加算ユニットを使用せず、直接マイクロ
コンピュータに変位信号を入力し、デジタル信号に変え
てから、ロジックまたはプログラム上で、前記の差動回
路、加算回路または極性反転回路に相当する演Ｘを行う
装置を使用したでも、本実施例と同様の効果が得られた
。この時には、測定ディスクの変位計測と参照ディスク
の変位計測を、各々−周ずつ準時に行っても、得られた
結果は同じであった。The displacement signal is input directly to the microcomputer without using a differential unit or an addition unit, converted to a digital signal, and then executed in logic or program to perform an operation equivalent to the differential circuit, addition circuit, or polarity inversion circuit described above. Even when a device that performs X was used, the same effects as in this example were obtained. At this time, even if the measurement of the displacement of the measurement disk and the measurement of the displacement of the reference disk were performed quasi-simultaneously for each round, the obtained results were the same.
本発明により、移動台の送り精度に対する要求を緩和で
き、また精度低下に対する保守が簡略化され経済的であ
る。また回転軸との直角出しが不要になり、移動台と回
転軸の取外し保守が可卵となる。磁気ディスクの全表面
の微小な高さのうねりを回転中に軸振れをキャンセルし
ながら高精度に測定できる装置は、これまで報告されて
おらず、本装置はこの点で新しい機能である。According to the present invention, the requirement for the feed accuracy of the movable table can be relaxed, and maintenance to prevent deterioration of accuracy is simplified and economical. In addition, it is no longer necessary to set the movable table at right angles to the rotary shaft, and the movable table and rotary shaft can be removed for maintenance. Until now, no device has been reported that can accurately measure minute height waviness on the entire surface of a magnetic disk while canceling axial runout during rotation, and this device is new in this respect.
第１図は、本発明の一実施例の構収図、第２図は従来技
術の概略説明図、第３図は本発明実施例に於ける参照デ
ィスクを用いた較正結果を示す線図、第４図は、同じく
参照ディスク用いた較正結果を示すグラフ。第５図は、
本発明実施例に於ける他の変位センサ配置法を示す構収
図、第６図は、本発明実施例に於ける、他の較正方法ブ
ロック図である。
１・・・参照変位センサ、２・・・測足ＩＩＣ極、３・
・・ディスク、５・・・差動ユニット、６・・・変位電
圧変換回路、７・・・記録計、８・・・モータ、１０・
・・移動台。
２１−ノリ％［’ｌ宅づ［＝６を噌ｒｔｖ己 ２ｚ・ブ
ξζＪ哨ど１貸二イｉｆｌ ２３−メ呵ト１シ夫難棺
イ噴二呵ヒン玉＝躬 ２凹
５ ６′ ７
躬４０
半必装置（ｍ −ｎ ）
第６０FIG. 1 is a composition diagram of an embodiment of the present invention, FIG. 2 is a schematic explanatory diagram of the prior art, and FIG. 3 is a diagram showing the calibration results using a reference disk in the embodiment of the present invention. FIG. 4 is a graph showing the calibration results using the same reference disk. Figure 5 shows
FIG. 6, a composition diagram showing another displacement sensor arrangement method in an embodiment of the present invention, is a block diagram of another calibration method in an embodiment of the present invention. 1... Reference displacement sensor, 2... Foot measuring IIC pole, 3...
...Disk, 5...Differential unit, 6...Displacement voltage conversion circuit, 7...Recorder, 8...Motor, 10...
・・Moving table. 21-Nori % ['l home [=6 噌rtvself 2z・buξζJ扫do 1 loan 2iiifl 23-Meto 1shifufu coffin Ispun 2呵hin ball=躬 2 dents 5 6' 7 謬 40 Semi-necessary equipment (m - n ) No. 60
Claims (1)
用いて該磁気ディスク表面の反りの形状を計測する基板
形状測定装置に於いて、該磁気ディスクと同じ回転軸に
固定して回転させ、予め形状の測定されている参照円板
表面の変位と該磁気ディスク表面の変位とを、同じ移動
台上に固定された非接触形変位計で同時または準次に測
定し、該磁気ディスクの変位量を該参照円板の変位量を
もとに、電気的またはマイクロコンピュータを用いた演
算により較正し、更に必要に応じて予め測定された該参
照円板の形状をもとにして、該マイクロコンピュータを
用いて、較正することにより測定精度の向上を計ること
を特徴とする磁気ディスク検査装置。1. In a substrate shape measuring device that measures the shape of warpage on the surface of a magnetic disk using a non-contact displacement meter while rotating the magnetic disk, the device is fixed to the same rotation axis as the magnetic disk and rotated; The displacement of the reference disk surface whose shape has been measured in advance and the displacement of the magnetic disk surface are measured simultaneously or quasi-sequentially with a non-contact displacement meter fixed on the same moving table, and the displacement of the magnetic disk is measured. The amount is calibrated electrically or by calculation using a microcomputer based on the amount of displacement of the reference disk, and if necessary, the microcomputer is calibrated based on the shape of the reference disk measured in advance. A magnetic disk inspection device characterized by improving measurement accuracy by calibrating using a computer.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP30751487A JPH01148904A (en) | 1987-12-07 | 1987-12-07 | Apparatus for inspecting magnetic disk |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP30751487A JPH01148904A (en) | 1987-12-07 | 1987-12-07 | Apparatus for inspecting magnetic disk |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH01148904A true JPH01148904A (en) | 1989-06-12 |
Family
ID=17969993
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP30751487A Pending JPH01148904A (en) | 1987-12-07 | 1987-12-07 | Apparatus for inspecting magnetic disk |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH01148904A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2006300778A (en) * | 2005-04-21 | 2006-11-02 | Tohoku Univ | Surface shape measuring apparatus |
| JP2007305286A (en) * | 2006-04-11 | 2007-11-22 | Hitachi High-Technologies Corp | Magnetic disk defect test method, protrusion test device, and glide tester |
-
1987
- 1987-12-07 JP JP30751487A patent/JPH01148904A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2006300778A (en) * | 2005-04-21 | 2006-11-02 | Tohoku Univ | Surface shape measuring apparatus |
| JP2007305286A (en) * | 2006-04-11 | 2007-11-22 | Hitachi High-Technologies Corp | Magnetic disk defect test method, protrusion test device, and glide tester |
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