JPH04147428A - Magnetic disk - Google Patents
Magnetic diskInfo
- Publication number
- JPH04147428A JPH04147428A JP27395890A JP27395890A JPH04147428A JP H04147428 A JPH04147428 A JP H04147428A JP 27395890 A JP27395890 A JP 27395890A JP 27395890 A JP27395890 A JP 27395890A JP H04147428 A JPH04147428 A JP H04147428A
- Authority
- JP
- Japan
- Prior art keywords
- thin film
- metal thin
- radial direction
- ferromagnetic metal
- head
- 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
- 230000005291 magnetic effect Effects 0.000 title claims abstract description 19
- 229910052751 metal Inorganic materials 0.000 claims abstract description 11
- 239000002184 metal Substances 0.000 claims abstract description 11
- 230000005294 ferromagnetic effect Effects 0.000 claims abstract description 10
- 239000010409 thin film Substances 0.000 claims abstract description 10
- 239000010408 film Substances 0.000 abstract description 17
- 239000000758 substrate Substances 0.000 abstract description 9
- VTYYLEPIZMXCLO-UHFFFAOYSA-L Calcium carbonate Chemical compound [Ca+2].[O-]C([O-])=O VTYYLEPIZMXCLO-UHFFFAOYSA-L 0.000 abstract description 4
- -1 polyethylene terephthalate Polymers 0.000 abstract description 4
- 239000011247 coating layer Substances 0.000 abstract description 3
- 239000010419 fine particle Substances 0.000 abstract description 3
- 229920000139 polyethylene terephthalate Polymers 0.000 abstract description 3
- 239000005020 polyethylene terephthalate Substances 0.000 abstract description 3
- 229910052684 Cerium Inorganic materials 0.000 abstract description 2
- 239000004734 Polyphenylene sulfide Substances 0.000 abstract description 2
- 229910000019 calcium carbonate Inorganic materials 0.000 abstract description 2
- 235000010216 calcium carbonate Nutrition 0.000 abstract description 2
- 230000007423 decrease Effects 0.000 abstract description 2
- 229920000069 polyphenylene sulfide Polymers 0.000 abstract description 2
- 229910020630 Co Ni Inorganic materials 0.000 abstract 1
- 229910002440 Co–Ni Inorganic materials 0.000 abstract 1
- 238000005299 abrasion Methods 0.000 abstract 1
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 abstract 1
- 229910052593 corundum Inorganic materials 0.000 abstract 1
- RSEIMSPAXMNYFJ-UHFFFAOYSA-N europium(III) oxide Inorganic materials O=[Eu]O[Eu]=O RSEIMSPAXMNYFJ-UHFFFAOYSA-N 0.000 abstract 1
- 125000005487 naphthalate group Chemical group 0.000 abstract 1
- 229910001845 yogo sapphire Inorganic materials 0.000 abstract 1
- 239000010410 layer Substances 0.000 description 7
- 229910018487 Ni—Cr Inorganic materials 0.000 description 4
- 230000000694 effects Effects 0.000 description 4
- 230000001681 protective effect Effects 0.000 description 4
- 238000004544 sputter deposition Methods 0.000 description 4
- 230000000052 comparative effect Effects 0.000 description 3
- 235000014113 dietary fatty acids Nutrition 0.000 description 3
- 229930195729 fatty acid Natural products 0.000 description 3
- 239000000194 fatty acid Substances 0.000 description 3
- 150000004665 fatty acids Chemical class 0.000 description 3
- 239000004642 Polyimide Substances 0.000 description 2
- 239000000314 lubricant Substances 0.000 description 2
- 230000005415 magnetization Effects 0.000 description 2
- 239000010702 perfluoropolyether Substances 0.000 description 2
- 238000007747 plating Methods 0.000 description 2
- 229920001721 polyimide Polymers 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 229910020517 Co—Ti Inorganic materials 0.000 description 1
- 229910020515 Co—W Inorganic materials 0.000 description 1
- 229910000861 Mg alloy Inorganic materials 0.000 description 1
- 229910003271 Ni-Fe Inorganic materials 0.000 description 1
- 239000004696 Poly ether ether ketone Substances 0.000 description 1
- 239000004952 Polyamide Substances 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 229910052804 chromium Inorganic materials 0.000 description 1
- 238000004140 cleaning Methods 0.000 description 1
- 229910017052 cobalt Inorganic materials 0.000 description 1
- 239000010941 cobalt Substances 0.000 description 1
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 description 1
- 238000005566 electron beam evaporation Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 229910021385 hard carbon Inorganic materials 0.000 description 1
- 150000002500 ions Chemical class 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 229910052750 molybdenum Inorganic materials 0.000 description 1
- 229910052759 nickel Inorganic materials 0.000 description 1
- 238000005457 optimization Methods 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 229920001643 poly(ether ketone) Polymers 0.000 description 1
- 229920003207 poly(ethylene-2,6-naphthalate) Polymers 0.000 description 1
- 229920002647 polyamide Polymers 0.000 description 1
- 229920000728 polyester Polymers 0.000 description 1
- 229920006393 polyether sulfone Polymers 0.000 description 1
- 229920002530 polyetherether ketone Polymers 0.000 description 1
- 239000011112 polyethylene naphthalate Substances 0.000 description 1
- 229920006254 polymer film Polymers 0.000 description 1
- 229910052707 ruthenium Inorganic materials 0.000 description 1
- 150000003839 salts Chemical class 0.000 description 1
- 229910000702 sendust Inorganic materials 0.000 description 1
- 229910052715 tantalum Inorganic materials 0.000 description 1
Landscapes
- Compositions Of Macromolecular Compounds (AREA)
- Magnetic Record Carriers (AREA)
Abstract
Description
【発明の詳細な説明】
産業上の利用分野
本発明は磁気記録密度を高めることのできる磁気ディス
クに関する。DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a magnetic disk capable of increasing magnetic recording density.
従来の技術
従来、Ｃｏ Ｐ ＊ Ｃｏ Ｎ ｔ Ｐめっき膜
。Conventional technology Conventionally, CoP*CoNtP plating film.
Ｃｏ−Ｎｉ、Ｃｏ−Ｎｉ−Ｃｒスパッタ膜等の強磁性金
属薄膜を磁気記録層とする磁気ディスクは高密度記録に
適するものとして期待され、一部の系で実用に供されて
いる。これらの磁気ディスクは耐久信頼性に難点があり
、直接ヘッドと強磁性金属薄膜が接触することのないよ
うコバルト熱酸化膜やスピンコード５ｉ０２膜、Ｒｈめ
っき膜等の保護膜を配したり［特公昭５Ｃ）−１４３８
号公報。Magnetic disks whose magnetic recording layer is a ferromagnetic metal thin film such as a Co--Ni or Co--Ni-Cr sputtered film are expected to be suitable for high-density recording, and some systems are in practical use. These magnetic disks have problems with durability and reliability, and protective films such as cobalt thermal oxide films, spin code 5i02 films, Rh plating films, etc. are provided to prevent direct contact between the head and the ferromagnetic metal thin film. Kosho 5C)-1438
Publication No.
特開昭５２−１０４９０３号公報、特公昭５７６１７７
号公報］、基板表面に傷を入れて接触面積を減らしたり
［特開昭６１−２０２３２４号公報、特開昭６３−２２
５９１９号公報］、号公報法の改善提案［特開昭６３−
１７７３１４号公報、特開昭６３−１７７３１３号公報
１等が続けられている。Japanese Patent Publication No. 52-104903, Japanese Patent Publication No. 576177
No. 61-202324, Japanese Patent Application Laid-open No. 63-22, the surface of the substrate is scratched to reduce the contact area.
No. 5919], a proposal for improvement of the method [Unexamined Japanese Patent Publication No. 1983-
Publication No. 177314, Japanese Unexamined Patent Publication No. 177313/1983, etc. are continuing.
発明が解決しようとする課題
しかしながら、上記した構成を採用しても、フロッピー
ディスクでの耐久信頼性は十分ではなく、経時的にエラ
ー率が劣化するといった課題があり改善が望まれていた
。Problems to be Solved by the Invention However, even if the above configuration is adopted, the durability and reliability of the floppy disk is not sufficient, and there is a problem that the error rate deteriorates over time, and an improvement has been desired.
本発明は上記した事情に鑑みなされたもので、エラー率
の安定した磁気ディスクを提供するものである。The present invention was made in view of the above-mentioned circumstances, and it is an object of the present invention to provide a magnetic disk with a stable error rate.
課題を解決するための手段
上記した課題を解決するため本発明の磁気ディスクは、
粒状突起を有する強磁性金属薄膜が半径方向に膜厚傾斜
をもつようにしたものである。Means for Solving the Problems In order to solve the above-mentioned problems, the magnetic disk of the present invention has the following features:
A ferromagnetic metal thin film having granular protrusions has a thickness gradient in the radial direction.
作用
本発明の磁気ディスクは上記した構成により、粒状突起
の拡がりが半径方向で変化することになるので、トラッ
ク移動時にヘッド前面への衝撃が変化し、清浄化作用で
、ヘッドと媒体間に短波長でスペーシング損失として影
響を大きく与える異物介在を許さなくなるので、良好な
高密度記録特性を維持できる。Function: Due to the above-described structure of the magnetic disk of the present invention, the spread of the granular protrusions changes in the radial direction, so the impact on the front surface of the head changes during track movement, and the cleaning effect creates a short distance between the head and the medium. Since the presence of foreign matter that significantly affects the wavelength as a spacing loss is not allowed, good high-density recording characteristics can be maintained.
実施例
以下、図面を参照しながら本発明の一実施例について説
明する。第１図は本発明の一実施例の磁気ディスクの拡
大断面図で、第２図は本発明の同磁気ディスクの上面図
である。第１図で１はポリエチレンテレフタレート、ポ
リエチレンナフタレート、ポリフェニレンサルファイド
、ポリエーテルケトン、ポリエーテルエーテルケトン、
ポリエーテルサルフオン、ポリアミド、ポリイミド等の
高分子フィルムや、ガラス、ＡＩ！ −Ｍｇ合金等の基
板である。２はＡＱ ２０３．、ＣａＣＯ３，Ｅｕ２Ｏ
３゜Ｈｆ ０２＋ ＭｇＯ，Ｚ ｒＯ２，Ｓ ｉ ０２
．ポリエステル球、ポリイミド球等の微粒子塗布層で、
直径６０Ａから３５ＯＡのものを、０．１〜１００ケ／
（μｍ）２の範囲で配したものが好ましい。３はＣｏ−
Ｎｉ。Embodiment Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is an enlarged sectional view of a magnetic disk according to an embodiment of the present invention, and FIG. 2 is a top view of the same magnetic disk according to the present invention. In Figure 1, 1 is polyethylene terephthalate, polyethylene naphthalate, polyphenylene sulfide, polyether ketone, polyether ether ketone,
Polymer films such as polyether sulfon, polyamide, polyimide, glass, AI! - A substrate made of Mg alloy or the like. 2 is AQ 203. , CaCO3, Eu2O
3゜Hf 02+ MgO,Z rO2,S i 02
．． With a coating layer of fine particles such as polyester spheres and polyimide spheres,
0.1 to 100 pieces/diameter 60A to 35OA
(μm)2 is preferable. 3 is Co-
Ni.
Ｃｏ−Ｃｅ、Ｃｏ−Ｃｒ、Ｃｏ−Ｔａ、Ｃｏ−Ｔｉ。Co-Ce, Co-Cr, Co-Ta, Co-Ti.
Ｃｏ−Ｍｏ、Ｃｏ−Ｗ、Ｃｏ−Ｒｕ、Ｃｏ−Ｎｉ−Ｃｒ
、Ｃｏ−Ｃｒ−Ｎｂ等の強磁性金属薄膜で電子ビーム蒸
着法、イオンブレーティング法、スパッタリング法等に
より形成するもので必要であれば、Ｔｉ、Ｓｉ、Ｇｅ、
Ｃｒ等の下地層やＮｉ−Ｆｅ等の軟磁性層を介して形成
してもよい。本発明は第２図に示したようにディスク上
面の磁気記録層５で、半径方向ｒに関して、上記した強
磁性金属薄膜の膜厚がＡからＢへ増大傾向か又はその逆
に減少傾向の傾斜をもつようにしたもので、そのことに
より形成される粒状突起の拡がりが径方向に傾斜をもつ
ことになり、研磨性を異ならせトラック移動時にヘッド
前面の清浄化をはかれるようになるのである。そのため
必要な膜厚傾斜は、記録再生に用いる部分の範囲で５％
から１５％の範囲がよい。１５％以上では電磁変換特性
面で不利が生じるからである。４は保護潤滑剤層でプラ
ズマ重合層、カーボン膜、脂肪酸、脂肪酸アミド、脂肪
酸の金属塩、パーフルオロポリエーテル等を組み合わせ
たものでスペーシング損失が大きくならないで所望の保
護効果を得ることができるような最適化が望まれる。本
発明は片面アクセスか両面アクセスかについて限定され
るものではなく、フロッピーディスクであれハードディ
スクであれ採用できる。但し、ハードディスクでは本発
明の効果は耐Ｃ８Ｓ性の改善に対して発揮されるもので
広義にはエラー率の経時安定性の確保といえるものであ
る。Co-Mo, Co-W, Co-Ru, Co-Ni-Cr
, Co-Cr-Nb or other ferromagnetic metal thin film formed by electron beam evaporation, ion blating, sputtering, etc. If necessary, Ti, Si, Ge,
It may be formed through an underlayer such as Cr or a soft magnetic layer such as Ni-Fe. As shown in FIG. 2, in the magnetic recording layer 5 on the upper surface of the disk, the thickness of the ferromagnetic metal thin film described above tends to increase from A to B, or vice versa, with respect to the radial direction r. As a result, the spread of the granular protrusions formed has an inclination in the radial direction, which changes the abrasiveness and makes it possible to clean the front surface of the head during track movement. Therefore, the required film thickness gradient is 5% in the area used for recording and reproduction.
A range of 15% is preferable. This is because if it exceeds 15%, there will be disadvantages in terms of electromagnetic conversion characteristics. 4 is a protective lubricant layer which is a combination of a plasma polymerized layer, a carbon film, a fatty acid, a fatty acid amide, a metal salt of a fatty acid, a perfluoropolyether, etc., and can obtain the desired protective effect without increasing the spacing loss. Such optimization is desired. The present invention is not limited to single-sided or double-sided access, and can be applied to either floppy disks or hard disks. However, in the case of hard disks, the effect of the present invention is exhibited in improving C8S resistance, and in a broad sense, it can be said to ensure stability of error rate over time.
以下、フロッピーディスクの例で具体的に本発明につい
て比較例との対比で説明する。Hereinafter, the present invention will be specifically explained using the example of a floppy disk in comparison with a comparative example.
［実施例−１］
厚み４０μｍのポリエチレンテレフタレートフィルム上
に直径１００Ａの５ｉ０２微粒子を１５ケ／（μｍ）２
配し、Ｃｏ−Ｎ１−Ｃｒ（Ｃｏ：Ｎｉ：Ｃｒ＝８０：１
４：６ｗｔ％）をターゲットにして、スリットを設け、
ターゲットと基板をずらし、５インチのディスク状にし
た基板を回転しながら、ＡからＢへ向かって記録部（半
径方向で１４＋ｎｍ）でＣｏ−Ｎｉ−Ｃｒ膜厚が１０５
０Ａから１１８０Ａへ厚くなるようにつけたもの（ディ
スク■）と、逆に１２００Ａから１０５０Ａへと薄くな
るもの（ディスク■）の２種類を高周波スパッタリング
法で製造した。保護潤滑層として、グラファイトをター
ゲットにしてＡ ｒ ＋Ｈ２−０，０８（Ｔｏ ｒ ｒ
）、Ａ ｒ：Ｈ２−１： ３゜１３、５６ （ＭＨｚ）
、 １ （ｋｗ）でスパッタリングして、８０Ａのダ
イアモンド状硬質炭素膜を配しその上にパーフルオロポ
リエーテルとして市販のモンテフルオス社製のフオンブ
リンＺ−２５を０．５■／−配し、５インチディスクと
した。[Example-1] 15 particles of 5i02 with a diameter of 100A/(μm)2 were placed on a polyethylene terephthalate film with a thickness of 40 μm.
arrangement, Co-N1-Cr (Co:Ni:Cr=80:1
4:6 wt%) and provided a slit,
While rotating the 5-inch disk-shaped substrate by shifting the target and the substrate, the Co-Ni-Cr film thickness was 105 at the recording part (14+nm in the radial direction) from A to B.
Two types of discs were manufactured using a high-frequency sputtering method: one in which the thickness increases from 0A to 1180A (disk ■) and one in which the thickness decreases from 1200A to 1050A (disc ■). As a protective lubricant layer, A r + H2-0,08 (To r r
), A r:H2-1: 3゜13,56 (MHz)
, a diamond-like hard carbon film of 80A was deposited by sputtering at 1 (kw), and on top of that, 0.5 cm/- of Foomblin Z-25 manufactured by Montefluos, a commercially available perfluoropolyether, was deposited to form a 5-inch film. It was made into a disc.
［実施例−２１
実施例−１の基板を用い、Ｃｏ−Ｃｒ（Ｃｏ：８０ｗｔ
％）をターゲットにし、ターゲットと基板を傾け、スリ
ットを用い、基板を回転しながら、Ｃｏ−Ｃｒ垂直磁化
膜をスパッタリング法で形成した。ＡからＢへ向かって
、１９００Ａから２ ］、 ＯＯＡへと厚くしたもの（
ディスク■）、その逆に２１００Ａから１９００Ａへと
薄（したものを（ディスク■）準備し、他は同じ構成で
５インチディスクを得た。[Example 21 Using the substrate of Example 1, Co-Cr (Co: 80wt
%), a Co--Cr perpendicular magnetization film was formed by sputtering while tilting the target and substrate and rotating the substrate using a slit. From A to B, from 1900A to 2], thickened to OOA (
On the other hand, a 5-inch disk was prepared with the same configuration except for the disk (■), which was thinned from 2100A to 1900A (disk ■).
［比較例−１１
実施例−１でＣｏ−Ｎｉ−Ｃｒ膜を均一に１１００Ａ形
成（厳密には２５Ａ程度の不均一性がある。）した以外
は同じ条件でディスクを得た。Comparative Example 11 A disk was obtained under the same conditions as in Example 1, except that a Co-Ni-Cr film was uniformly formed at a thickness of 1100A (strictly speaking, there was a non-uniformity of about 25A).
［比較例−２］
実施例−２でＣｏ−Ｃｒ垂直磁化膜を２０００人形成し
た以外は同じ条件でディスクを得た。[Comparative Example-2] A disk was obtained under the same conditions as in Example-2 except that 2000 Co--Cr perpendicular magnetization films were formed.
上記したディスクをギャップ長０．１８μｍのセンダス
トスパッタ膜を用いたメタルインギヤ・ツブ型リングヘ
ッドでビット長０．２２μｍ、トラック幅３０μｍの記
録再生を行い、エラー率を比較した。エラー率は任意の
１０トラツクを選び計測した値の平均値を初期値とし、
経時安定性は初期値で規格化し、最小値と最大値の範囲
で示した。Recording and reproduction were performed on the above-mentioned disk using a metal-in-gear knob type ring head using a sendust sputtered film with a gap length of 0.18 μm with a bit length of 0.22 μm and a track width of 30 μm, and the error rates were compared. The initial value of the error rate is the average value of the values measured by selecting 10 arbitrary tracks.
The stability over time was normalized by the initial value and expressed as the range between the minimum and maximum values.
発明の効果
以上のように本発明によれば、ヘッド・ディスク間のス
ペーシングロスとなる異物介在が殆どみられず、経時的
にもエラー率の変化が小さく、高密度記録可能な磁気デ
ィスクが得られるといったすぐれた効果がある。Effects of the Invention As described above, according to the present invention, there is almost no foreign matter that causes spacing loss between the head and the disk, and the error rate changes little over time, making it possible to create a magnetic disk capable of high-density recording. There are excellent effects that can be obtained.
第１図は本発明の一実施例に係わる磁気ディスクの拡大
断面図、第２図は同磁気ディスクの上面図である。
１・・・・・・基板、２・・・・・・微粒子塗布層、３
・・・・・・強磁性金属薄膜、５・・・・・・磁気記録
層。FIG. 1 is an enlarged sectional view of a magnetic disk according to an embodiment of the present invention, and FIG. 2 is a top view of the same magnetic disk. 1... Substrate, 2... Fine particle coating layer, 3
...Ferromagnetic metal thin film, 5...Magnetic recording layer.
Claims (1)
をもつことを特徴とする磁気ディスク。A magnetic disk characterized in that a ferromagnetic metal thin film having granular protrusions has a thickness gradient in the radial direction.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP27395890A JPH04147428A (en) | 1990-10-11 | 1990-10-11 | Magnetic disk |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP27395890A JPH04147428A (en) | 1990-10-11 | 1990-10-11 | Magnetic disk |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH04147428A true JPH04147428A (en) | 1992-05-20 |
Family
ID=17534946
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP27395890A Pending JPH04147428A (en) | 1990-10-11 | 1990-10-11 | Magnetic disk |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH04147428A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100438802B1 (en) * | 1996-12-17 | 2004-08-31 | 삼성전자주식회사 | A quantum disk and a method for fabricating the same |
| CN100380453C (en) * | 2004-03-25 | 2008-04-09 | Tdk股份有限公司 | Information recording medium |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH02149919A (en) * | 1988-11-30 | 1990-06-08 | Matsushita Electric Ind Co Ltd | Magnetic disk |
-
1990
- 1990-10-11 JP JP27395890A patent/JPH04147428A/en active Pending
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH02149919A (en) * | 1988-11-30 | 1990-06-08 | Matsushita Electric Ind Co Ltd | Magnetic disk |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100438802B1 (en) * | 1996-12-17 | 2004-08-31 | 삼성전자주식회사 | A quantum disk and a method for fabricating the same |
| CN100380453C (en) * | 2004-03-25 | 2008-04-09 | Tdk股份有限公司 | Information recording medium |
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