JPS60187923A - Vertical magnetization recording medium - Google Patents

Abstract

PURPOSE:To obtain a reproducing signal having a high output value and high resolution by selecting a medium so that a magnetic recording layer has a axis easy for magnetization in a direction perpendicular to the film face and its magnetic characteristic has a prescribed value. CONSTITUTION:The vertical magnetization recording head is constituted that a high-permeability magnetic thin film 16 is opposed closely to the vertical magnetization film 11, a high-permeability magnetic member 14 is arranged at the opposite side while clipping a recording medium and an exciting coil 15 is wound. The vertical magnetic recording medium is formed that a resistance magnetic layer 12 if formed on a nonmagnetic base 13, the axis easy for magnetization is provided in a direction perpendicular to the film face on the layer, the saturated magnetic flux density is 400-800emv/cc, the coercive force is 600-800 Oersted and the anisotropic magnetic field is 2-3k Oersted by using the vertical magnetization film 11. Then the reproduction with high resolution and high density is attained by applying a recording current to the exciting coil 15 to excite the magnetic member 14, concentrating, the magnetic flux on the medium opposed face of the magnetic thin film 16 to magnetize vertically the magnetizing film 11.

Description

【発明の詳細な説明】 （技術分野） 本発明は、垂直磁化記録媒体、すなわち磁気記（従来技
術） 磁気記録における記録密度の向上にともない、従来の磁
気記録媒体の膜面に平行に磁化記録を行う方式では、減
磁界の影響を減少させるため、媒体を薄膜化する等、種
々の方法が行なわれているが、実際には、限界近い状態
となっている。これに対し、近年、媒体の膜面に対し垂
直な方向に記録を行う垂直磁化記録方式が提案され、現
在に紋るまで盛んに研究が行なわれている。Detailed Description of the Invention (Technical Field) The present invention relates to a perpendicular magnetization recording medium, that is, a magnetic recording medium (prior art). In order to reduce the influence of the demagnetizing field, various methods have been used, such as making the medium thinner, but in reality they are close to reaching their limits. On the other hand, in recent years, a perpendicular magnetization recording method in which recording is performed in a direction perpendicular to the film surface of the medium has been proposed, and has been actively researched to this day.

垂直記録の記録再呈方式としては、膜面に対して垂直な
方向に一軸異方性を有する六方晶系の結晶構造を有する
Ｃ０系合金あるいろＢａ−フェライト等の薄膜（以後垂
直磁化膜と呼ぶ）と１通常の長手記録用のリングヘッド
との組み合わせによる記録再生方式と、前記垂直磁化膜
をイ氏抗磁力材からなる磁性薄膜上に形成した二層構造
の媒体と、高透磁率で且つ低抗磁力を有する磁性薄膜か
らなるヘッドを直接あるいは間接的に励磁して前記垂直
磁化膜に垂直に磁化記録を行う方式とがある。As a recording re-presentation method of perpendicular recording, a thin film (hereinafter referred to as perpendicular magnetization film) of a C0 alloy or Ba-ferrite having a hexagonal crystal structure with uniaxial anisotropy in the direction perpendicular to the film surface is used. 1) A recording/reproducing method combining a conventional ring head for longitudinal recording, a two-layer structure medium in which the perpendicular magnetization film is formed on a magnetic thin film made of I-coercive material, and a high magnetic permeability medium. Another method is to directly or indirectly excite a head made of a magnetic thin film having low coercive force to record magnetization perpendicularly to the perpendicularly magnetized film.

前者は孤立反転磁化に対応する再生波形は双峰性のパル
ス波形（ダイパルス波形）となり、波形等化あるいは符
号の制約等の条件が非常に厳しくなり、実際の装置とし
ては現在に致るまで製品化されていない。後者の場合に
は、再生波形は単峰性のパルス波形となり、前者のよう
な問題はない。In the former case, the reproduced waveform corresponding to isolated inversion magnetization is a bimodal pulse waveform (dipulse waveform), and conditions such as waveform equalization and sign restrictions are extremely strict, and as a result, as an actual device, it has not been possible to manufacture products until now. has not been standardized. In the latter case, the reproduced waveform becomes a unimodal pulse waveform, and there is no problem like the former.

このような二層構造の記録媒体は、記録過程においては
、低抗磁力層内に磁性薄膜からなるヘッドの影像磁化が
生じ、前記ヘッドから発生する磁界を強める作用をする
。また、この低抗磁力層によって、垂直磁化膜の裏面の
磁気回路を部分的に閉じ、減磁作用を軽減し、残留磁化
を強めることが可能となる。In such a two-layered recording medium, during the recording process, image magnetization of the head made of a magnetic thin film occurs in the low coercive force layer, which acts to strengthen the magnetic field generated from the head. Moreover, this low coercive force layer makes it possible to partially close the magnetic circuit on the back surface of the perpendicularly magnetized film, reduce demagnetization effect, and strengthen residual magnetization.

しかし、このような効果が記録再生において有効に働く
には、垂直磁化膜の磁気％性１％に、異方性磁界Ｈｋ、
膜面に垂直な方向の抗磁力ＨｃＬ、更に飽和磁化Ｍ、が
最も良い状態ｐ値に選定されなければならない。However, in order for such an effect to work effectively in recording and reproduction, an anisotropic magnetic field Hk,
The coercive force HcL in the direction perpendicular to the film surface and the saturation magnetization M must be selected to have the best p value.

また、二層構造の媒体と、低抗磁力を有する磁性薄膜と
の組み合わせによる再生信号の出力レベルは非常に低い
ために、信号対維音比の向上は必要欠くべからざる条件
である。Furthermore, since the output level of the reproduced signal produced by the combination of the two-layer structure medium and the magnetic thin film having low coercive force is extremely low, improvement of the signal-to-sound ratio is an essential condition.

更に、再生におけるエラー！−ジンを拡大するためには
、高分解能な記録密度の領域で使用せざるを得ないため
１分解能の向上も必要である。Furthermore, errors in playback! - In order to enlarge the resolution, it is necessary to improve the resolution by 1 because it has to be used in a high-resolution recording density area.

（発明の目的） 本発明の目的は、かかる点にかんがみ、高出力値で高分
解能をもつ再生信号を得ることのできる二層構造の垂直
磁化記録の媒体を提供することである。(Object of the Invention) In view of the above points, an object of the present invention is to provide a perpendicular magnetization recording medium with a two-layer structure capable of obtaining a reproduced signal with a high output value and high resolution.

（発明の構成） 本発明によれば、単極型主磁極を有する磁気ヘッドの前
記主磁極に近接対向、ないしは接触対向する磁気記録層
と低抗磁力材層とを具備し、前記磁気ヘッドの漏洩磁束
によって記録がなされる垂直磁化記録媒体において、前
記磁気記録層が膜面に垂直な方向に磁化容易軸を有し、
前記磁気記録層の飽和磁束密度を４　Ｑ　Ｑ　ｅｍｖ／
ｃ　ｃ　后８００　ｅｍｖ７ｃｃに、前記磁気記録層の
抗磁力を６００エルステツド乃至８００エルステツドに
、前記磁気記録層の異方性磁界を２キロエルステツド乃
至３キロエルステツドに選定することを特徴とする垂直
磁化記録媒体が得られる。(Structure of the Invention) According to the present invention, a magnetic head having a unipolar main pole includes a magnetic recording layer and a low coercive force material layer that are closely opposed to or in contact with the main pole of the magnetic head. In a perpendicular magnetization recording medium in which recording is performed by leakage magnetic flux, the magnetic recording layer has an axis of easy magnetization in a direction perpendicular to the film surface,
The saturation magnetic flux density of the magnetic recording layer is 4 Q Q emv/
c c 800 emv7cc, a perpendicular magnetization recording medium characterized in that the coercive force of the magnetic recording layer is selected from 600 oersted to 800 oersted, and the anisotropic magnetic field of the magnetic recording layer is selected from 2 kilooersted to 3 kilooersted. can get.

（実施例） 以下図面を用いて本発明の実施例について説明する。(Example) Embodiments of the present invention will be described below with reference to the drawings.

第１図は本発明の一実施例の垂直磁化記録媒体と基本的
な垂直磁化記録ヘッドとの構成図を示している。FIG. 1 shows a configuration diagram of a perpendicular magnetization recording medium and a basic perpendicular magnetization recording head according to an embodiment of the present invention.

ポリエステル等よりなる非磁性基体１３上にスパッタリ
ング等により、低抗磁力層１２を形成し、その上にスパ
ッタリングあるいは蒸着等により膜面に対して垂直な方
向に磁化容易軸を有し、飽和磁束密度が４００　ｅｍｖ
／ｃ　ｃ乃至８００ｅｍｖ／ｃｃとし。A low coercive force layer 12 is formed by sputtering or the like on a non-magnetic substrate 13 made of polyester or the like, and a low coercive force layer 12 is formed thereon by sputtering or vapor deposition, and has an axis of easy magnetization in a direction perpendicular to the film surface, and has a saturation magnetic flux density. is 400 emv
/cc c to 800emv/cc.

抗磁力が６００エルステツド（以後Ｏｅと表す）乃至８
０００ｅとし、異方性磁界が２ＫＯｅ乃至３ＫＯｅとな
るよう垂直磁化膜１１を形成する。Coercive force is 600 oersted (hereinafter referred to as Oe) to 8
000e, and the perpendicular magnetization film 11 is formed so that the anisotropic magnetic field is 2KOe to 3KOe.

垂直磁化記録ヘッドは、高透磁率磁性薄膜１６を垂直磁
化膜１１に近接対向し記録媒体をはさんで反対側に高透
磁率磁性部材１４を配置し、励磁コイル１５を高透磁率
磁性部材１４に巻層した構成からなっている。励磁コイ
ル１５に記録電流を印加し、高透磁率磁性部材１４を励
磁し、磁束が漏洩すると、高透磁率磁性薄膜１６の媒体
対向面近傍に磁束が集中し、垂直磁化膜１１を垂直に磁
化する。The perpendicular magnetization recording head has a high permeability magnetic thin film 16 facing the perpendicular magnetization film 11 in close proximity and a high permeability magnetic member 14 on the opposite side with the recording medium in between, and an excitation coil 15 connected to the high permeability magnetic member 14. It consists of a layered structure. When a recording current is applied to the excitation coil 15 to excite the high permeability magnetic member 14 and the magnetic flux leaks, the magnetic flux concentrates near the medium facing surface of the high permeability magnetic thin film 16 and magnetizes the perpendicularly magnetized film 11 perpendicularly. do.

このような構成によれば、高分解能で高密度の記録再生
が可能となる。According to such a configuration, high-resolution and high-density recording and reproduction is possible.

第２図は垂直磁化膜の磁気特性を変化させシミュレーシ
冒ンにより最大再生出力値を示したものであり、記録再
生の条件はスペーシングを０１１５μｍとし、高透磁率
磁性薄膜を００とＺｎとの合金とし、膜厚を０．３μｍ
とし、記録密度を５０ＫＢＰＩとした。実線で示した曲
線は等しい出力値を結んだものである。抗磁力ＨｃＬに
対して見ると、６０００ｅ以下では急激な出力低下が見
られ、８０００ｅ以上に対しても同様の傾向がみられる
。異方性磁界Ｈｋに対して見ると、抗磁力ＨＣＬと飽和
磁束密度Ｍ、の値が高い場合に２ＫＯｅ以下と３ＫＯｅ
以下で出力が低下している。飽和磁束密度Ｍ、に対して
見ると４００ｅｍｖ／ｃｃ以下及び８ＱＱｅｍｖ／ｃｃ
以上において出力が低下している。Figure 2 shows the maximum reproduction output value by running simulations by changing the magnetic properties of the perpendicularly magnetized film.The recording and reproduction conditions were a spacing of 0115 μm, and high permeability magnetic thin films of 00 and Zn. with a film thickness of 0.3 μm.
The recording density was set to 50KBPI. The curve shown as a solid line connects equal output values. When looking at the coercive force HcL, a sharp drop in output is seen below 6000e, and a similar tendency is seen above 8000e. Looking at the anisotropic magnetic field Hk, when the values of coercive force HCL and saturation magnetic flux density M are high, 2KOe or less and 3KOe
The output is reduced below. When looking at the saturation magnetic flux density M, 400 emv/cc or less and 8QQemv/cc
In the above conditions, the output is reduced.

従って、実施例で示したようにＨ８Ｌ、Ｍ、及びＨｋＯ
値の選定することにより、高出力な再生信号が得られる
。Therefore, as shown in the example, H8L, M, and HkO
By selecting the value, a high output reproduction signal can be obtained.

第３図は垂直磁化膜の磁気特性を変化させたときの分解
能を示したものである。ここで分解能は記録密度５０Ｋ
ＤＰＩにおける最大再生出力値と２５ＫＢＰＩにおける
最大再生出力β値の比としこれをチで示した。記録再生
の条件は第２図における条件と同一で行った。FIG. 3 shows the resolution when changing the magnetic properties of the perpendicularly magnetized film. Here, the resolution is recording density 50K
This is the ratio of the maximum reproduction output value at DPI and the maximum reproduction output β value at 25KBPI, and is shown by H. The recording and reproducing conditions were the same as those shown in FIG.

実線で示した曲線は等しい分解能を結んだものである。The solid curves connect the same resolution.

抗磁力Ｈ８ＬＫ対して見ると７０００．で最大値を持ち
１両端に向って単調に減少していく。The coercive force is 7000 compared to H8LK. It has a maximum value at 1 and decreases monotonically toward both ends.

分解能を８０−以上とすると６０００．以下及び８００
０ｅ以上ではこれを満足できない。異方性磁界Ｈｋに対
して見ると１．５　Ｋ　Ｏ，以下及び３．５ＫＯｅ以下
では分解能８０％以上を満足できない。飽和磁束密度Ｍ
、に対して見ると３５ｏｅｍｖ／ｃｃ以下及び８００ｅ
ｍｖ／ｃｃ以上では分解能８０チ以上を満足できない。If the resolution is 80- or more, it is 6000. Below and 800
Above 0e, this cannot be satisfied. When looking at the anisotropic magnetic field Hk, a resolution of 80% or higher cannot be achieved at 1.5 KO or less and 3.5 KOe or less. Saturation magnetic flux density M
, 35oemv/cc or less and 800e
If it is mv/cc or more, the resolution of 80 inches or more cannot be satisfied.

従って、実施例で示したようにＨｃＬｌＭ、及び、）（
ｋの値を選定することにより高分解能な再生信号を得る
ことができる。Therefore, as shown in the example, HcLlM and )(
By selecting the value of k, a high-resolution reproduction signal can be obtained.

（発明の効果） 本発明によると、高出力値で高分解能をもつ再生信号を
得る効果がある。(Effects of the Invention) According to the present invention, there is an effect of obtaining a reproduced signal having a high output value and high resolution.

【図面の簡単な説明】[Brief explanation of drawings]

第１図は本発明の一実施例の垂直磁化記録媒体と基本的
な垂直磁化記録ヘッドとの栴成図、第２図は垂直磁化膜
の磁匈特性を変化させたときの最大再生出力値の特性図
、第３図は垂直磁化膜の磁気特性を変化させたときの分
解能の特性図を示している。 １１・・・・・・垂直磁化膜、１２・・・・・・抵抗磁
力層。 １３・・・・・・非磁性基板、１４・・・・・・高透磁
率磁性部材、１５・・・・・・励磁コイル、１６・・山
高透磁率磁性薄膜竿　ｌＩ！ｌFigure 1 is a schematic diagram of a perpendicular magnetization recording medium according to an embodiment of the present invention and a basic perpendicular magnetization recording head, and Figure 2 is the maximum reproduction output value when changing the magnetic force characteristics of the perpendicular magnetization film. FIG. 3 shows a characteristic diagram of the resolution when the magnetic properties of the perpendicularly magnetized film are changed. 11... Perpendicular magnetization film, 12... Resistive magnetic layer. 13...Nonmagnetic substrate, 14...High permeability magnetic member, 15...Excitation coil, 16...High permeability magnetic thin film rod lI! l

Claims (1)

【特許請求の範囲】[Claims] 単極型土ａｉｉを有する磁気ヘッドの前記主磁極に近接
対向、ないしは接触対向する磁気記録層と１（５，抗磁
力材層とを具備し、前記磁気ヘッドの漏洩磁束によって
記録がなされる垂直磁化記録媒体において、前記磁気記
録層が膜面に垂直な方向に磁化容易軸を有し、前記磁気
記録層の飽和磁束密度を４００　ｅｍｖ／ｃ　ｃ乃至８
００ｅｍｖ／ｃｃに、前記磁気記録層の膜面に垂直な方
向の抗磁力を６００エルステツド乃至８００エルステツ
ドに、前記磁気記録層の異方性磁界を２キロエルステツ
ド乃至３キロエルステツドに選定したことを特徴とする
垂直磁化記録媒体A magnetic head having a single-pole type soil AII includes a magnetic recording layer closely facing or contacting the main pole, and a coercive material layer 1 (5), and a perpendicular magnetic head on which recording is performed by leakage magnetic flux of the magnetic head. In the magnetic recording medium, the magnetic recording layer has an axis of easy magnetization in a direction perpendicular to the film surface, and the saturation magnetic flux density of the magnetic recording layer is 400 emv/cc to 8.
00 emv/cc, the coercive force in the direction perpendicular to the film surface of the magnetic recording layer is set to 600 to 800 Oersted, and the anisotropic magnetic field of the magnetic recording layer is set to 2 to 3 Kiloersted. Perpendicular magnetization recording medium