JPH0224815A - Magnetic recording medium - Google Patents
Magnetic recording mediumInfo
- Publication number
- JPH0224815A JPH0224815A JP17393688A JP17393688A JPH0224815A JP H0224815 A JPH0224815 A JP H0224815A JP 17393688 A JP17393688 A JP 17393688A JP 17393688 A JP17393688 A JP 17393688A JP H0224815 A JPH0224815 A JP H0224815A
- Authority
- JP
- Japan
- Prior art keywords
- magnetic
- film
- layer
- recording medium
- anisotropic film
- 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.)
- Granted
Links
- 239000000758 substrate Substances 0.000 claims abstract description 8
- 230000005415 magnetization Effects 0.000 abstract description 8
- 229910052782 aluminium Inorganic materials 0.000 abstract description 2
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 abstract description 2
- 238000007747 plating Methods 0.000 abstract description 2
- 229910018104 Ni-P Inorganic materials 0.000 abstract 1
- 229910018536 Ni—P Inorganic materials 0.000 abstract 1
- 238000010030 laminating Methods 0.000 abstract 1
- 239000010410 layer Substances 0.000 description 23
- 238000000034 method Methods 0.000 description 11
- 230000007423 decrease Effects 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 229910052759 nickel Inorganic materials 0.000 description 3
- 229910052804 chromium Inorganic materials 0.000 description 2
- 230000008878 coupling Effects 0.000 description 2
- 238000010168 coupling process Methods 0.000 description 2
- 238000005859 coupling reaction Methods 0.000 description 2
- 230000004907 flux Effects 0.000 description 2
- 239000000696 magnetic material Substances 0.000 description 2
- 229910000889 permalloy Inorganic materials 0.000 description 2
- 229920000139 polyethylene terephthalate Polymers 0.000 description 2
- 239000005020 polyethylene terephthalate Substances 0.000 description 2
- 230000001681 protective effect Effects 0.000 description 2
- 229910000859 α-Fe Inorganic materials 0.000 description 2
- MYMOFIZGZYHOMD-UHFFFAOYSA-N Dioxygen Chemical compound O=O MYMOFIZGZYHOMD-UHFFFAOYSA-N 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 238000013459 approach Methods 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 229910001882 dioxygen Inorganic materials 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- -1 polyethylene terephthalate Polymers 0.000 description 1
- 239000011148 porous material Substances 0.000 description 1
- 229920006395 saturated elastomer Polymers 0.000 description 1
- 239000002356 single layer Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000007738 vacuum evaporation Methods 0.000 description 1
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は磁気記録媒体に係り、さらに詳しくは磁気ヘッ
ドと磁気記録媒体との距離が大きいワイドスペーシング
であっても優れた磁気記録再生特性を示す垂直磁気異方
性膜を有する磁気記録媒体に関する。[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a magnetic recording medium, and more specifically, it provides excellent magnetic recording and reproducing characteristics even in wide spacing where the distance between a magnetic head and a magnetic recording medium is large. The present invention relates to a magnetic recording medium having a perpendicular magnetic anisotropic film.
近年、高密度記録の需要の増加に伴い、新しい記録方式
の検討が活発に行われている。中でも磁気記録の分野で
は、垂直磁気記録方式が有望な高密度記録の一方法とし
て盛んに検討されている（テレビジョン学会誌Ｖｏ１．
３９． Ｎｏ、４ （１９８５）第３５７頁から第３６
５頁〕。In recent years, with the increasing demand for high-density recording, new recording methods have been actively studied. In the field of magnetic recording, perpendicular magnetic recording is being actively studied as a promising high-density recording method (Television Society Journal Vol. 1.
39. No. 4 (1985) pp. 357-36
5 pages].
この垂直磁気記録方式の最大の特徴とするところは、記
録密度の増加と共に記録磁化に加わる反磁界が減少し、
自己減磁の影響を免かれ得ることができるからである。The biggest feature of this perpendicular magnetic recording method is that as the recording density increases, the demagnetizing field applied to the recorded magnetization decreases.
This is because the influence of self-demagnetization can be avoided.
したがって、垂直磁気記録方式は本質的に高密度磁気記
録に適した方式であると言うことができる。しかし、こ
の垂直磁気記録方式に問題が無いわけではない。すなわ
ち、垂直磁気記録方式においては、磁気ヘッドと記録媒
体間の距離（以下、スペーシングと言う）が、従来の面
内記録方式の場合に比べて記録再生特性に大きな影響を
与え、狭いスペーシング領域においてのみ垂直磁気記録
方式の本質的な優位性が保たれるが、逆にスペーシング
が広く（大きく）なると面内記録方式の方が特性面で優
位になる傾向にある。このスペーシングの依存性は、特
にリングヘッドと単層膜媒体との組合せにおいて著しく
、垂直磁気記録方式を実用化する上での一つの大きな問
題となっていた。Therefore, it can be said that the perpendicular magnetic recording method is essentially a method suitable for high-density magnetic recording. However, this perpendicular magnetic recording method is not without its problems. In other words, in the perpendicular magnetic recording method, the distance between the magnetic head and the recording medium (hereinafter referred to as spacing) has a greater effect on the recording and reproducing characteristics than in the case of the conventional longitudinal recording method. The essential superiority of the perpendicular magnetic recording method is maintained only in the area, but on the other hand, when the spacing becomes wider (larger), the longitudinal recording method tends to be superior in terms of characteristics. This spacing dependence is particularly noticeable in the combination of a ring head and a single-layer film medium, and has been a major problem in putting the perpendicular magnetic recording system into practical use.
上述したごとく、従来技術における垂直磁気記録媒体は
、磁気ヘッドと磁気記録媒体との距離が大きい、いわゆ
るワイドスペーシングの場合においては高密度磁気記録
が達成できないという問題があった。As described above, the conventional perpendicular magnetic recording medium has the problem that high-density magnetic recording cannot be achieved in the case of so-called wide spacing, in which the distance between the magnetic head and the magnetic recording medium is large.
本発明の目的は、上記従来技術の間層点を解消し、磁気
ヘッドと磁気記録媒体との距離が大きいワイドスペーシ
ングであっても優れた記録再生特性を示す垂直磁気異方
性膜を有する磁気記録媒体を提供することにある。An object of the present invention is to eliminate the above-mentioned problems of the prior art, and to provide a perpendicular magnetic anisotropic film that exhibits excellent recording and reproducing characteristics even in wide spacing where the distance between the magnetic head and the magnetic recording medium is large. The purpose of this invention is to provide a magnetic recording medium.
上記本発明の目的は、非磁性基板上に、直接もしくは下
地層を介して垂直磁気異方性膜を形成し、この垂直磁気
異方性膜上に、直接もしくは非磁性の中間層を介して軟
磁性材料からなる軟磁性層を設けることにより、達成さ
れる。The object of the present invention is to form a perpendicular magnetic anisotropic film on a non-magnetic substrate directly or through an underlayer, and to form a perpendicular magnetic anisotropic film on the perpendicular magnetic anisotropic film directly or through a non-magnetic intermediate layer. This is achieved by providing a soft magnetic layer made of a soft magnetic material.
本発明の磁気記録媒体において、垂直磁気異方性膜を構
成する磁性材料は、特に限定するものではないが、例え
ばＣｏ−Ｃｒ、Ｃｏ−０，Ｆｅ−０などからなる垂直磁
気異方性膜、あるいはアルマイト微細孔中に磁性体を充
填した形態の垂直磁気異方性膜を用いることができる。In the magnetic recording medium of the present invention, the magnetic material constituting the perpendicular magnetic anisotropic film is not particularly limited; for example, a perpendicular magnetic anisotropic film made of Co-Cr, Co-0, Fe-0, etc. Alternatively, a perpendicular magnetic anisotropic film in which a magnetic substance is filled in fine alumite pores can be used.
本発明の磁気記録媒体において、垂直磁気異方性膜上に
設ける軟磁性層は、その膜厚が１０〜１１００ｎの範囲
で、保磁力が１００ＸＩＯ３／（４π）Ａ／ｍ（１００
Ｏｅ）以下の特性を示すものであればよく、例えばＮｉ
、ＦｅまたはＣｏなどの単体金属もしくはこれらを主成
分とする合金、あるいはＮｉ、 ＦｅまたはＧｏを含む
フェライト膜などを好適に用いることができる。また、
垂直磁気異方性膜の上に。In the magnetic recording medium of the present invention, the soft magnetic layer provided on the perpendicular magnetic anisotropic film has a thickness in the range of 10 to 1100 nm and a coercive force of 100XIO3/(4π)A/m (100
Oe) Any material may be used as long as it exhibits the following characteristics, for example, Ni
Single metals such as , Fe, or Co, or alloys containing these as main components, or ferrite films containing Ni, Fe, or Go can be suitably used. Also,
on top of a perpendicular magnetic anisotropic film.
直接軟磁性層を形成させると７両者の磁気的カプリング
により軟磁性層が硬質磁性層化してしまう場合があるが
、この場合には５０ｎ ｍ以下の非磁性中間層を設ける
ことにより解決される。なお、非磁性中間層の膜厚が５
０ｎ ｍを超えると、両者の磁気的結合が弱くなり過ぎ
るので、軟磁性層の磁化が垂直磁気異方性膜の漏洩磁場
に追従しなくなるので好ましくない。さらに、当然のこ
とであるが、非磁性基板と垂直磁気異方性膜との間にも
、軟磁性層あるいは非磁性の下地層を設けて、記録磁化
の安定化あるいは垂直磁気異方性膜の磁気特性の改善を
はかることができることは言うまでもない。If the soft magnetic layer is formed directly, the soft magnetic layer may turn into a hard magnetic layer due to magnetic coupling between the two, but this can be solved by providing a nonmagnetic intermediate layer with a thickness of 50 nm or less. Note that the thickness of the nonmagnetic intermediate layer is 5
If it exceeds 0 nm, the magnetic coupling between the two becomes too weak and the magnetization of the soft magnetic layer no longer follows the leakage magnetic field of the perpendicular magnetic anisotropic film, which is not preferable. Furthermore, as a matter of course, a soft magnetic layer or a non-magnetic underlayer is provided between the non-magnetic substrate and the perpendicular magnetic anisotropic film to stabilize the recorded magnetization or to stabilize the perpendicular magnetic anisotropic film. Needless to say, it is possible to improve the magnetic properties of.
本発明の磁気記録媒体の作動原理を第１図により説明す
る。磁気ヘッドにより本発明の磁気記録媒体に記録を行
う際には１表面の軟磁性層１の膜厚が薄いため比較的に
容易に飽和し、磁気ヘッドの磁界分布は大きく乱される
ことがない。その結果、軟磁性層１の下部に存在する垂
直磁気異方性膜２は垂直磁気記録される６そして、垂直
磁気異方性膜２の表面に現れる漏洩磁場により軟磁性層
１が磁化され、面内磁化の記録パターンが磁気記録媒体
の表面に残ることになる。ついで、このように記録され
た媒体の表面に磁気ヘッドが近づくと、磁気ヘッドは媒
体の軟磁性層１表面の面内記録パターンからの磁束を検
出し、再生信号が得られる。このようにして、本発明の
磁気記録媒体では、記録を高分解能の垂直記録で行うこ
とができ。The operating principle of the magnetic recording medium of the present invention will be explained with reference to FIG. When recording on the magnetic recording medium of the present invention with a magnetic head, since the thickness of the soft magnetic layer 1 on one surface is thin, it is relatively easily saturated, and the magnetic field distribution of the magnetic head is not significantly disturbed. . As a result, the perpendicular magnetic anisotropic film 2 existing under the soft magnetic layer 1 is perpendicularly magnetically recorded6, and the soft magnetic layer 1 is magnetized by the leakage magnetic field appearing on the surface of the perpendicular magnetic anisotropic film 2. A recorded pattern of in-plane magnetization remains on the surface of the magnetic recording medium. Then, when the magnetic head approaches the surface of the medium recorded in this way, the magnetic head detects the magnetic flux from the in-plane recording pattern on the surface of the soft magnetic layer 1 of the medium, and a reproduced signal is obtained. In this way, in the magnetic recording medium of the present invention, recording can be performed with high resolution perpendicular recording.
また再生の際には、面内磁化成分を利用することから再
生時のスペーシング損失を大きく低減することができる
。その結果、リジッドディスクのようにスペーシングの
大きい磁気記録の分野においても、優れた高密度記録性
能および高い再生出力を得ることができる。Furthermore, since the in-plane magnetization component is used during reproduction, spacing loss during reproduction can be greatly reduced. As a result, excellent high-density recording performance and high reproduction output can be obtained even in the field of magnetic recording with large spacing such as rigid disks.
なお、本発明の磁気記録媒体における軟磁性層１の膜厚
は、ｌθ〜１００ｎ ｍの範囲にあることが好ましく、
ｌＯｎｍ未満では再生出力の低下を引き起し、１００ｎ
ｍを超えると磁気ヘッドからの磁束が垂直磁気異方性
膜２に浸透しにくくなるため垂直磁気記録が充分にでき
なくなるため好ましくない、また、軟磁性層１の保磁力
は１００ＸＩＯ”／（４π）Ａ／ｍ以下であることが好
ましく、１００ＸＩＯ３／ （４７ｃ）Ａ／ｍを超える
と軟磁性層１の磁化が記録された垂直磁気異方性膜２か
らの漏洩磁場に追従しなくなり。The thickness of the soft magnetic layer 1 in the magnetic recording medium of the present invention is preferably in the range of lθ to 100 nm,
If it is less than 1Onm, the reproduction output will decrease, and if it is less than 100nm,
If it exceeds m, it becomes difficult for the magnetic flux from the magnetic head to penetrate into the perpendicular magnetic anisotropic film 2, making perpendicular magnetic recording insufficient. ) A/m or less, and if it exceeds 100XIO3/(47c) A/m, the magnetization of the soft magnetic layer 1 will no longer follow the leakage magnetic field from the recorded perpendicular magnetic anisotropic film 2.
著しい出力低下を引き起すので好ましくない。This is not preferable because it causes a significant decrease in output.
以下に本発明の一実施例を挙げ、さらに詳細に説明する
。An example of the present invention will be described below in more detail.
（実施例 １）
アルミニウム基板上に、厚さ１０μ個のＮ１−Ｐメツキ
を施し、さらにその上に配向制御用のＧｅ膜（５０ｎ
ｍ ）、垂直磁気異方性膜としてｃｏ７．ｃｒ２．ＷＡ
（２００ｎ’ｍ ）を積層し、この上に軟磁性層として
Ｎｉ、、Ｃｒ、膜を、膜厚を０から２００ｎ ｍの範囲
内で種々変化させて形成し磁気記録媒体の試料を第１表
に示すごとく、１〜８種類作製した。(Example 1) N1-P plating with a thickness of 10 μm was applied on an aluminum substrate, and a Ge film (50 nm
m), co7. as a perpendicular magnetic anisotropic film. cr2. W.A.
(200 nm), and on top of this, Ni, Cr, and Ni films were formed as soft magnetic layers with varying film thicknesses within the range of 0 to 200 nm. Samples of magnetic recording media are shown in Table 1. As shown in the figure, 1 to 8 types were produced.
作製した試料の記録再生特性は、ギャップ長さ０．４μ
ｍのＭｎ−Ｚｎフェライトヘッドを用い、１０ｋｆｃｉ
および６０ｋｆｃｉにおける出力を求め評価した。The recording and reproducing characteristics of the prepared sample were as follows: gap length 0.4μ
10kfci using Mn-Zn ferrite head
The output at 60 kfci was determined and evaluated.
なお、出力（ｄ Ｂ ）の値は、軟磁性層であるパーマ
ロイ膜の膜厚が０の場合をＯｄＢとし、これを基準にし
て比較値で表した。その結果を、第１表に示す。Note that the value of the output (dB) is OdB when the thickness of the permalloy film, which is a soft magnetic layer, is 0, and is expressed as a comparative value using this as a reference. The results are shown in Table 1.
第１表から明らかなごとく、本発明のパーマロイ膜の膜
厚を１０〜１１００ｎとした軟磁性層を設けた磁気記録
媒体は、いずれも優れた再生特性を示すことが分かる。As is clear from Table 1, all the magnetic recording media provided with the soft magnetic layer of the permalloy film of the present invention having a thickness of 10 to 1100 nm exhibit excellent reproduction characteristics.
（実施例２）
厚さ４０μＩのＰＥＴ （ポリエチレンテレフタレート
）基板上に、酸素ガスを導入しながらＧｏを蒸発させて
Ｇｏ−０からなる垂直磁気異方性膜を。(Example 2) On a PET (polyethylene terephthalate) substrate with a thickness of 40 μI, Go was evaporated while introducing oxygen gas to form a perpendicular magnetic anisotropic film made of Go-0.
真空蒸着法によって膜厚３５０ｎ ｍに成膜し、その上
に軟磁性層としてＣＯ単体膜をＯから２００ｎ ｍの範
囲に膜厚を種々変化させて形成し、さらに保護膜として
Ｓｉ膜を５０ｎ ｍの膜厚に設けた磁気記録媒体の試料
を、第２表に示すごとく、１〜７種類作製した。作製し
た試料の記録再生特性の評価方法は、実施例１と同様で
あるが、磁気ヘッドとのスペーシングは、保護膜の膜厚
５０ｎ ｍにヘッドの平均浮上量５０ｎ ｍを加えた約
１１００ｎであった。その結果を、第２表に示す。A film with a thickness of 350 nm was formed by vacuum evaporation, and on top of this a CO film was formed as a soft magnetic layer with the film thickness varying from O to 200 nm, and a Si film was further formed as a protective film with a thickness of 50 nm. As shown in Table 2, 1 to 7 types of magnetic recording medium samples were prepared with a film thickness of . The method for evaluating the recording and reproducing characteristics of the prepared sample was the same as in Example 1, but the spacing with the magnetic head was approximately 1100 nm, which is the sum of the protective film thickness of 50 nm and the average flying height of the head of 50 nm. there were. The results are shown in Table 2.
第２表
膜を１０〜１１００ｎの範囲内で設けた磁気記録媒体は
、いずれも優れ再生特性を示すことが分がる。It can be seen that all the magnetic recording media in which the second surface film is provided within the range of 10 to 1100 nm exhibit excellent reproduction characteristics.
以上詳細に説明したごとく、本発明の垂直磁気異方性膜
上に、薄い所定の膜厚の軟磁性層を設けた磁気記録媒体
は、垂直磁気異方性膜の記録パターンを軟磁性層に転写
して、その面内磁化成分を磁気ヘッドで再生することが
可能となるので、スペーシング損失を著しく低減するこ
とができる効果がある。As explained in detail above, the magnetic recording medium of the present invention in which a thin soft magnetic layer of a predetermined thickness is provided on a perpendicular magnetic anisotropic film has a recording pattern of the perpendicular magnetic anisotropic film on the soft magnetic layer. Since it is possible to transfer and reproduce the in-plane magnetization component with a magnetic head, it is possible to significantly reduce spacing loss.
第１図は本発明の磁気記録媒体の基本的構成および作動
原理を示す模式図である。
１・・・軟磁性層
２・・・垂直磁気異方性膜
３・・・基板
代理人弁理士 中 村 純之助FIG. 1 is a schematic diagram showing the basic structure and operating principle of the magnetic recording medium of the present invention. 1... Soft magnetic layer 2... Perpendicular magnetic anisotropic film 3... Junnosuke Nakamura, patent attorney representing the substrate
Claims (1)
磁気異方性膜を形成し、該垂直磁気異方性膜上に、直接
もしくは非磁性中間層を介して軟磁性層を設けたことを
特徴とする磁気記録媒体。 ２、特許請求の範囲第１項の磁気記録媒体において、軟
磁性層の膜厚を１０〜１００ｎｍの範囲とすることを特
徴とする磁気記録媒体。 ３、特許請求の範囲第１項の磁気記録媒体において、軟
磁性層の膜厚を１０〜１００ｎｍの範囲となし、かつ軟
磁性層の保磁力を１００×１０＾３／（４π）Ａ／ｍ〔
１００Ｏｅ〕以下とすることを特徴とする磁気記録媒体
。[Claims] 1. A perpendicular magnetic anisotropic film is formed on a non-magnetic substrate directly or through an underlayer, and a perpendicular magnetic anisotropic film is formed directly or through a non-magnetic intermediate layer on the perpendicular magnetic anisotropic film. A magnetic recording medium characterized by being provided with a soft magnetic layer. 2. The magnetic recording medium according to claim 1, wherein the soft magnetic layer has a thickness in the range of 10 to 100 nm. 3. In the magnetic recording medium according to claim 1, the thickness of the soft magnetic layer is in the range of 10 to 100 nm, and the coercive force of the soft magnetic layer is 100×10^3/(4π) A/m. [
100 Oe] or less.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP17393688A JP2615144B2 (en) | 1988-07-14 | 1988-07-14 | Magnetic recording media |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP17393688A JP2615144B2 (en) | 1988-07-14 | 1988-07-14 | Magnetic recording media |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0224815A true JPH0224815A (en) | 1990-01-26 |
| JP2615144B2 JP2615144B2 (en) | 1997-05-28 |
Family
ID=15969814
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP17393688A Expired - Lifetime JP2615144B2 (en) | 1988-07-14 | 1988-07-14 | Magnetic recording media |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2615144B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7807278B2 (en) | 2003-09-30 | 2010-10-05 | Showa Denko K.K. | Perpendicular magnetic recording medium and magnetic storage apparatus |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2002197635A (en) * | 2000-12-28 | 2002-07-12 | Showa Denko Kk | Magnetic recording medium, method of manufacturing for the same and magnetic recording and reproducing device |
-
1988
- 1988-07-14 JP JP17393688A patent/JP2615144B2/en not_active Expired - Lifetime
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7807278B2 (en) | 2003-09-30 | 2010-10-05 | Showa Denko K.K. | Perpendicular magnetic recording medium and magnetic storage apparatus |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2615144B2 (en) | 1997-05-28 |
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