JPH02165411A - Perpendicular magnetic recording medium - Google Patents
Perpendicular magnetic recording mediumInfo
- Publication number
- JPH02165411A JPH02165411A JP32129488A JP32129488A JPH02165411A JP H02165411 A JPH02165411 A JP H02165411A JP 32129488 A JP32129488 A JP 32129488A JP 32129488 A JP32129488 A JP 32129488A JP H02165411 A JPH02165411 A JP H02165411A
- Authority
- JP
- Japan
- Prior art keywords
- magnetic
- layer
- film
- perpendicular magnetic
- recording medium
- 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
- 238000007747 plating Methods 0.000 claims abstract description 10
- 238000000034 method Methods 0.000 claims abstract description 9
- 239000000758 substrate Substances 0.000 claims description 6
- 229910003271 Ni-Fe Inorganic materials 0.000 abstract description 10
- 238000004544 sputter deposition Methods 0.000 abstract description 9
- 230000004304 visual acuity Effects 0.000 abstract 2
- 239000010408 film Substances 0.000 description 40
- 239000010936 titanium Substances 0.000 description 4
- 230000000694 effects Effects 0.000 description 3
- 239000010409 thin film Substances 0.000 description 3
- 230000005284 excitation Effects 0.000 description 2
- 230000004907 flux Effects 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 229910000702 sendust Inorganic materials 0.000 description 2
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 239000000919 ceramic Substances 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 230000035699 permeability Effects 0.000 description 1
- 230000002250 progressing effect Effects 0.000 description 1
- 230000008929 regeneration Effects 0.000 description 1
- 238000011069 regeneration method Methods 0.000 description 1
- 229910052719 titanium Inorganic materials 0.000 description 1
Landscapes
- Magnetic Record Carriers (AREA)
Abstract
Description
【発明の詳細な説明】
〔概 要〕
垂直磁気記録媒方式の磁気ディスク装置に用いられる二
層膜構造の垂直磁気記録媒体に関し、軟磁性層の機械的
強度を改善して、高記録分解能で、再生出力の富い、し
かも耐久性に優れた新規な二層膜構造の垂直磁気記録媒
体を得ることを目的とし、
非磁性基板上に軟磁性層を介して垂直磁気記録層を設け
た二層膜構造の記録媒体において、上記軟磁性層が硬質
な第一磁性膜と、その上にめっき法により形成する第二
磁性膜とからなる構成とする。[Detailed Description of the Invention] [Summary] Regarding a perpendicular magnetic recording medium with a double-layer structure used in a perpendicular magnetic recording medium type magnetic disk device, the mechanical strength of the soft magnetic layer is improved to achieve high recording resolution. , with the aim of obtaining a new perpendicular magnetic recording medium with a double-layer structure that has high reproduction output and excellent durability. In a recording medium having a layered film structure, the soft magnetic layer is composed of a hard first magnetic film and a second magnetic film formed thereon by a plating method.
本発明は垂直磁気記録媒方式の磁気ディスク装置に用い
られる垂直磁気記録媒体に係り、特に二層膜構造の垂直
磁気記録媒体の改良に関するものである。The present invention relates to a perpendicular magnetic recording medium used in a perpendicular magnetic recording medium type magnetic disk device, and particularly relates to an improvement of a perpendicular magnetic recording medium having a double-layer structure.
情報を磁気記録層の膜厚方向に磁化して記録する垂直磁
気記録媒体は、従来の水平記録方式の媒体に比べて遥か
に高密度記録が可能であることから注目され、近来、こ
れら垂直磁気記録媒体の実用化が活発に進めれている。Perpendicular magnetic recording media, which record information by magnetizing it in the thickness direction of the magnetic recording layer, have attracted attention because they are capable of much higher density recording than conventional horizontal recording media. The practical application of recording media is actively progressing.
垂直磁気記録媒体としては、磁気特性、記録再生特性及
び耐蝕性等の観点から高透磁率な軟磁性層と垂直磁気記
録層を順に積層した二層膜構造の垂直磁気記録媒体が最
も有利とされ、またこの記録媒体の作成手段としてはス
パッタリング法が主流となっている。このような垂直磁
気記録媒体では、高記録分解能で、再生出力の高い、し
かも耐久性に優れた媒体構造が必要とされている。As a perpendicular magnetic recording medium, a perpendicular magnetic recording medium having a two-layer structure in which a soft magnetic layer with high magnetic permeability and a perpendicular magnetic recording layer are sequentially laminated is considered to be the most advantageous from the viewpoint of magnetic properties, recording/reproducing characteristics, and corrosion resistance. Furthermore, the sputtering method is the mainstream method for producing this recording medium. Such perpendicular magnetic recording media require a medium structure with high recording resolution, high reproduction output, and excellent durability.
従来の二層膜構造の垂直磁気記録媒体の基本的な構造は
、第２図に示すように例えばアルマイト表面処理を施し
たアルミニウム（Ａ ｆ ）等からなる非磁性基板１上
に、スパッタリング法により例えば０．５μｍの膜厚の
Ｎｉ−Ｆｅからなる軟磁性層（軟磁性裏打ち層とも称す
る）２と、その軟磁性層２上に０．３μｍの膜厚のＣｏ
−Ｃｒからなる垂直磁気記録層３が順に積層状に配設さ
れた構成からなっている。The basic structure of a conventional perpendicular magnetic recording medium with a two-layer film structure is, as shown in FIG. For example, a soft magnetic layer (also referred to as a soft magnetic backing layer) 2 made of Ni-Fe with a thickness of 0.5 μm, and a Co layer with a thickness of 0.3 μm on the soft magnetic layer 2.
It has a configuration in which perpendicular magnetic recording layers 3 made of -Cr are sequentially arranged in a laminated manner.
そしてこのような構成の垂直磁気記録媒体への情報の記
録再生としては、該媒体面に所定間隔を隔てて対向する
例えば単磁極型の垂直記録再生用磁気ヘッドの励磁コイ
ルに通電する信号電流により主磁極先端より発生する磁
束が前記媒体の垂直磁気記録層３を垂直に通り、その直
下の軟磁性層２内を水平に通過して再び前記垂直磁気記
録層３を垂直に通って対向する前記磁気ヘッドの補助磁
極を経て前記主磁極へ帰還する磁気回路系によって記録
を行い、また上記のように情報が磁化−記録された前記
記録媒体の垂直磁気記録層３がらの漏洩磁束を前記磁気
ヘッドの主磁極で検出し、励磁コイルに生じる信号電圧
を出力することによって再生を行っている。Information is recorded and reproduced on a perpendicular magnetic recording medium having such a configuration by using a signal current that is applied to an excitation coil of, for example, a single-pole type perpendicular recording and reproducing magnetic head that faces the surface of the medium at a predetermined distance. The magnetic flux generated from the tip of the main magnetic pole passes perpendicularly through the perpendicular magnetic recording layer 3 of the medium, horizontally through the soft magnetic layer 2 immediately below it, and again perpendicularly passes through the perpendicular magnetic recording layer 3 to form the opposite side of the perpendicular magnetic recording layer 3. Recording is performed by a magnetic circuit system that returns to the main magnetic pole via the auxiliary magnetic pole of the magnetic head, and leakage magnetic flux from the perpendicular magnetic recording layer 3 of the recording medium on which information has been magnetized and recorded as described above is transferred to the magnetic head. Regeneration is performed by detecting the main magnetic pole of the magnet and outputting the signal voltage generated in the excitation coil.
ところで上記したような構成、の垂直磁気記録媒体にお
いては、高い再生出力を得るために前記Ｃｏ−Ｃｒから
なる垂直磁気記録層３の保磁力を大きくし、また記録分
解能を高めるために該垂直磁気記録層３の膜厚を薄くす
る必要がある。そのため第３図に示すように非磁性基板
１上に設けたＮｉ−Ｆｅからなる軟磁性層２上に、数百
オングストロームの膜厚のチタン（Ｔｉ）からなる中間
層１１を介在して０．２μｍ以下の薄い膜厚のＣｏ−Ｃ
ｒからなる垂直磁気記録層１２を設けて該垂直磁気記録
層１２の保磁力を高めた媒体構造が提案されている。By the way, in the perpendicular magnetic recording medium having the above-mentioned configuration, the coercive force of the perpendicular magnetic recording layer 3 made of Co--Cr is increased in order to obtain a high reproduction output, and the perpendicular magnetic recording layer 3 is increased in order to increase the recording resolution. It is necessary to reduce the thickness of the recording layer 3. Therefore, as shown in FIG. 3, an intermediate layer 11 made of titanium (Ti) with a thickness of several hundred angstroms is interposed on a soft magnetic layer 2 made of Ni--Fe provided on a non-magnetic substrate 1. Co-C with a thin film thickness of 2 μm or less
A media structure has been proposed in which a perpendicular magnetic recording layer 12 made of r is provided to increase the coercive force of the perpendicular magnetic recording layer 12.
しかし、そのような媒体構造における中間［１１の介在
は、記録再生時において当該媒体面と所定間隔を隔てて
対向する単磁極型垂直記録再生用磁気ヘッドの主磁極先
端と前記軟磁性層２との間隔を増加させるため、高める
べき記録分解能を逆に低下させてしまうといった欠点が
あった。However, in such a medium structure, the intermediate [11] is present between the tip of the main pole of the single-pole type perpendicular recording/reproducing magnetic head and the soft magnetic layer 2, which face the medium surface at a predetermined distance during recording and reproduction. This method has the drawback that the recording resolution, which should be improved, is reduced because the interval between the two is increased.
そこで上記した問題を解決するため、前記軟磁性層２と
してはスパッタリング法により形成するＮｉ−Ｆｅ層層
外外例えばＣｏ−Ｚｒ膜、或いはセンダスト膜（Ｆｅ−
５ｉ−Ａ ｊ２膜）等を用いることも試みたが、これら
の軟磁性層上に保磁力の大きいＣｏ−Ｃｒからなる垂直
磁気記録層を設けるには、やはり軟磁性層と垂直磁気記
録層との間にＴｉからなる中間層を介在する必要があっ
た。Therefore, in order to solve the above-mentioned problem, the soft magnetic layer 2 is made of a Ni--Fe layer formed by sputtering, for example, a Co--Zr film or a sendust film (Fe-
5i-Aj2 film), etc., but in order to provide a perpendicular magnetic recording layer made of Co-Cr with a large coercive force on these soft magnetic layers, it is still necessary to have a soft magnetic layer and a perpendicular magnetic recording layer. It was necessary to interpose an intermediate layer made of Ti between the two.
一方、めっき法により形成するＮｉ−Ｆｅ膜を用いた場
合には、その軟磁性層上にＴｉからなる中間層を介在さ
せずに保磁力の大きい改質の良い垂直磁気記録層を設け
ることができ、その結果、高い再生出力が得られると共
に、記録分解能が向上することが判明した。ところが前
記めっき法により形成するＮｉ−Ｆｅ膜はスパッタリン
グ法により形成したＮｉ−Ｆｅ膜と比べて、その膜自身
が柔らかいために磁気ヘッドの接触、衝撃等に対する耐
久性が低く、信相性の上で問題があった。On the other hand, when using a Ni-Fe film formed by plating, it is possible to provide a well-modified perpendicular magnetic recording layer with a large coercive force on the soft magnetic layer without intervening an intermediate layer made of Ti. It has been found that as a result, high reproduction output can be obtained and recording resolution can be improved. However, the Ni-Fe film formed by the plating method is softer than the Ni-Fe film formed by the sputtering method, so it has lower durability against contact with a magnetic head, impact, etc., and has poor reliability. There was a problem.
本発明は、上記した従来の問題点に鑑み、軟磁性層の機
械的強度を改善して、高記録分解能で、再生出力の高い
、しかも耐久性に優れた新規な二層膜構造の垂直磁気記
録媒体を提供することを目的とするものである。In view of the above-mentioned conventional problems, the present invention aims to improve the mechanical strength of the soft magnetic layer to provide a perpendicular magnetic layer with a novel two-layer film structure that has high recording resolution, high reproduction output, and excellent durability. Its purpose is to provide recording media.
本発明は上記した目的を達成するため、非磁性基板上に
軟磁性層を介して垂直磁気記録層を設けた二層膜構造の
記録媒体において、上記軟磁性層が硬質な第一磁性膜と
、その上にめっき法により形成した第二磁性膜とからな
る構成とする。In order to achieve the above object, the present invention provides a recording medium having a two-layer structure in which a perpendicular magnetic recording layer is provided on a non-magnetic substrate via a soft magnetic layer, in which the soft magnetic layer is a hard first magnetic film. , and a second magnetic film formed thereon by plating.
本発明の垂直磁気記録媒体ではスパッタリング法により
形成したＮｉ−Ｆｅ等からなる軟磁性膜は比較的硬質で
あり、その軟磁性膜上に直接薄い膜厚のＣｏ−Ｃｒから
なる垂直磁気記録層を設けた場合、該垂直磁気記録層の
保磁力が低下する。まためっき法により形成されたＮｉ
−Ｆｅ等からなる軟磁性膜は、前記スパッタリング法に
よるＮｉ−Ｐｅ等からなる軟磁性膜と比較して柔らかく
、その軟磁性膜上に薄い膜厚のＣｏ −Ｃｒからなる垂
直磁気記録層を設けた場合、該垂直磁気記録層の保磁力
は低下せずに維持される、といった軟磁性膜の硬度と、
成膜法による膜質の違う軟磁性膜上に設けられた藩い膜
厚のＣｏ−Ｃｒからなる垂直磁気記録層の保磁力の変化
に着目して、スパッタリング法等により形成した比較的
硬質なＮｉ−Ｐｅ等からなる軟磁性層（第一磁性膜）と
垂直磁気記録層との間に、従来介在させていたＴ１中間
層の代わりにめっき法で形成したＮｉ−Ｆｅ等からなる
軟磁性膜（第二磁性膜）を介在しているため、硬質の第
一磁性膜と第二磁性膜とで構成する軟磁性層の耐久性は
、その主体とする硬質の第一磁性膜の耐久性とほぼ同等
となり、記録分解能を低下させることなく、高い再生出
力を得ることができる。In the perpendicular magnetic recording medium of the present invention, the soft magnetic film made of Ni-Fe or the like formed by sputtering is relatively hard, and a thin perpendicular magnetic recording layer made of Co-Cr is directly formed on the soft magnetic film. When provided, the coercive force of the perpendicular magnetic recording layer is reduced. Also, Ni formed by plating method
The soft magnetic film made of -Fe etc. is softer than the soft magnetic film made of Ni-Pe etc. formed by the sputtering method, and a thin perpendicular magnetic recording layer made of Co -Cr is provided on the soft magnetic film. the hardness of the soft magnetic film such that the coercive force of the perpendicular magnetic recording layer is maintained without decreasing when
Focusing on changes in the coercive force of a perpendicular magnetic recording layer made of Co-Cr with a large film thickness, which is provided on a soft magnetic film with different film qualities depending on the film formation method, we developed a relatively hard Ni film formed by a sputtering method etc. - A soft magnetic film (first magnetic film) made of Ni-Fe etc. formed by plating method instead of the conventional T1 intermediate layer interposed between the soft magnetic layer (first magnetic film) made of -Pe etc. and the perpendicular magnetic recording layer. The durability of the soft magnetic layer composed of the hard first magnetic film and the second magnetic film is almost the same as that of the hard first magnetic film, which is the main component of the soft magnetic layer. Therefore, high reproduction output can be obtained without reducing recording resolution.
以下図面を用いて本発明の実施例について詳細に説明す
る。Embodiments of the present invention will be described in detail below with reference to the drawings.
第１図は本発明に係る垂直磁気記録媒体の一実施例を示
す要部断面図である。FIG. 1 is a sectional view of a main part of an embodiment of a perpendicular magnetic recording medium according to the present invention.
図において、２１は例えばアルマイト表面処理を施した
アルミニウム（Ａ／り、或いはガラス、セラミックなど
からなる非磁性基板であり、該非磁性基板２１上には、
例えばスパッタリング法により形成された０、３μｍの
膜厚のＮｉ−Ｆｅからなる硬質な第一磁性膜２２ａと、
その上にめっき法により形成された数百人の薄い膜厚の
Ｎｉ−Ｆｅからなる第二磁性膜２２ｂとからなる軟磁性
層２２を設けており、その軟磁性層２２の表面には従来
例と同様の例えば０．２μｍ以下の比較的薄い膜厚のＧ
ｏ−Ｃｒからなる垂直磁気記録層２３が設けられている
。In the figure, 21 is a non-magnetic substrate made of, for example, alumite surface-treated aluminum, glass, ceramic, etc. On the non-magnetic substrate 21,
For example, a hard first magnetic film 22a made of Ni-Fe with a film thickness of 0.3 μm formed by sputtering method,
On top of that, a soft magnetic layer 22 consisting of a second magnetic film 22b made of Ni-Fe with a thin film thickness of several hundred layers is formed by plating, and the surface of the soft magnetic layer 22 is G with a relatively thin film thickness of, for example, 0.2 μm or less, similar to
A perpendicular magnetic recording layer 23 made of o-Cr is provided.
従って、かかる構成の垂直位Ｊａ録媒体における軟磁性
層２２の耐久性、即ち磁気ヘッドの接触、衝撃に対する
耐久性は該軟磁性層２２主体となる硬質の第一磁性膜２
２ａの耐久性とほぼ同等に維持され、しかも記録分解能
を低下させずに高い再生出力が得られる。Therefore, the durability of the soft magnetic layer 22 in the vertical Ja recording medium with such a configuration, that is, the durability against contact with the magnetic head and impact, is limited to the hard first magnetic film 2 which is the main component of the soft magnetic layer 22.
The durability is maintained almost equal to that of 2a, and high reproduction output can be obtained without reducing the recording resolution.
なお、以上の実施例では軟磁性層を構成する硬質な第一
磁性膜として、スパッタリング法により形成されたＮｉ
−Ｆｅ膜を用いた場合の例について説明したが、本発明
はこの例に限定されるものではなく、例えばＣｏ −Ｚ
ｒ ％或いはセンダスト（Ｆｅ−３ｉ−Ａ ｌ ）等
からなる硬質な磁性膜を用いた場合にも同様な効果が得
られる。In the above embodiments, the hard first magnetic film constituting the soft magnetic layer is made of Ni formed by sputtering.
Although an example in which a -Fe film is used has been described, the present invention is not limited to this example; for example, a Co -Z film is used.
A similar effect can be obtained when using a hard magnetic film made of R% or sendust (Fe-3i-Al).
第１図は本発明に係る垂直磁気記録媒体の一実施例を示
す要部断面図、
第２図は従来の基本的な垂直磁気記録媒体を説説明する
ための要部断面図、
第３図は従来の垂直磁気記録媒体の他の例を示す要部断
面図である。
第１図において、
２１は非磁性基板、２２は軟磁性Ｎ、２２ａは第一磁性
膜、２２ｂは第二磁性膜、２３は垂直磁気記録層をそれ
ぞれ示す。
〔発明の効果］
以上の説明から明らかなように、本発明に係る垂直磁気
記録媒体によれば、高記録分解能で、しかも耐久性の優
れた高い再生出力の二層膜構造の垂直磁気記録媒体を容
易に得ることが可能となる利点を有し、実用上の効果は
大きい。FIG. 1 is a sectional view of a main part showing an embodiment of a perpendicular magnetic recording medium according to the present invention, FIG. 2 is a sectional view of a main part of a conventional basic perpendicular magnetic recording medium, and FIG. FIG. 2 is a cross-sectional view of a main part of another example of a conventional perpendicular magnetic recording medium. In FIG. 1, 21 is a nonmagnetic substrate, 22 is a soft magnetic N, 22a is a first magnetic film, 22b is a second magnetic film, and 23 is a perpendicular magnetic recording layer. [Effects of the Invention] As is clear from the above description, the perpendicular magnetic recording medium according to the present invention has a double-layer structure perpendicular magnetic recording medium with high recording resolution, excellent durability, and high reproduction output. It has the advantage that it can be easily obtained, and has great practical effects.
Claims (1)
磁気記録層（２３）を設けた二層膜構造の記録媒体にお
いて、 上記軟磁性層（２２）が硬質な第一磁性膜（２２ａ）と
、その上にめっき法により形成する第二磁性膜（２２ｂ
）とからなることを特徴とする垂直磁気記録媒体。[Claims] A recording medium having a two-layer structure in which a perpendicular magnetic recording layer (23) is provided on a non-magnetic substrate (21) via a soft magnetic layer (22), wherein the soft magnetic layer (22) is A hard first magnetic film (22a) and a second magnetic film (22b) formed thereon by a plating method.
) A perpendicular magnetic recording medium comprising:
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP32129488A JPH02165411A (en) | 1988-12-19 | 1988-12-19 | Perpendicular magnetic recording medium |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP32129488A JPH02165411A (en) | 1988-12-19 | 1988-12-19 | Perpendicular magnetic recording medium |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH02165411A true JPH02165411A (en) | 1990-06-26 |
Family
ID=18130965
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP32129488A Pending JPH02165411A (en) | 1988-12-19 | 1988-12-19 | Perpendicular magnetic recording medium |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH02165411A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6846583B2 (en) | 2000-11-09 | 2005-01-25 | Hitachi Maxell, Ltd. | Magnetic recording medium and magnetic recording apparatus |
-
1988
- 1988-12-19 JP JP32129488A patent/JPH02165411A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6846583B2 (en) | 2000-11-09 | 2005-01-25 | Hitachi Maxell, Ltd. | Magnetic recording medium and magnetic recording apparatus |
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