JPS6052919A - Vertical magnetic recording medium and its production - Google Patents
Vertical magnetic recording medium and its productionInfo
- Publication number
- JPS6052919A JPS6052919A JP16077683A JP16077683A JPS6052919A JP S6052919 A JPS6052919 A JP S6052919A JP 16077683 A JP16077683 A JP 16077683A JP 16077683 A JP16077683 A JP 16077683A JP S6052919 A JPS6052919 A JP S6052919A
- Authority
- JP
- Japan
- Prior art keywords
- magnetic
- substrate
- disk
- recording
- 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
Abstract
Description
【発明の詳細な説明】
本発明はフロッピー・ディスク及び磁気ディスク装置等
に使用される磁気記録体、特に垂直磁気記録方式に適し
た磁気記録体及びその製造方法に関する。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a magnetic recording body used in floppy disks, magnetic disk drives, etc., and particularly to a magnetic recording body suitable for perpendicular magnetic recording, and a method for manufacturing the same.
垂直磁気記録方式は、第１図及び第２図に示す様に記録
媒体面に垂直方向の磁化状態として情報を記録するもの
であり、従来の面内記録方式に比べて原理的に短波長特
性が勝れ、高密度記録が可能という点で注目されている
。As shown in Figures 1 and 2, the perpendicular magnetic recording system records information as a magnetization state perpendicular to the surface of the recording medium, and in principle has shorter wavelength characteristics than the conventional in-plane recording system. It is attracting attention because of its superior performance and its ability to perform high-density recording.
この方式に用いる磁気記録体としては、基体ｌ上に形成
した垂直方向（厚さ方向）に磁化容易軸を持つＣｏＣｒ
合金、バリウムフェライトなどの磁気記録層２（以下、
垂直磁化膜）もしくは、この垂直磁化膜２と基体との間
にＮｉＦｅ合金等の高透磁率磁性層３を有する２層膜が
知られている。The magnetic recording material used in this method is a CoCr film with an axis of easy magnetization in the perpendicular direction (thickness direction), which is formed on a substrate L.
Magnetic recording layer 2 made of alloy, barium ferrite, etc. (hereinafter referred to as
A two-layer film having a high permeability magnetic layer 3 of NiFe alloy or the like between the perpendicular magnetization film 2 and the substrate is known.
又、磁気ヘッドとしては、高透磁率磁性膜から成る短冊
状の主磁極４と記録再生用巻線６を有しかつ、主磁極４
より十分厚い磁性体から成る補助磁極５とを記録体９又
は１ｏを挾んで配置したもの、もしくは記録体９又は１
ｏの片面側だけで記録再生ができる様に短冊状の主磁極
７に記録再生用巻線８を施したもの等が用いられる。そ
してこれらの磁気ヘッドを用いる場合には、先述した２
層膜を用いることによって記録再生効率が向上すること
が知られており、基体１と垂直磁化膜２との間に設けた
高透磁率磁性層３の効果が注目されている。The magnetic head has a rectangular main pole 4 made of a high permeability magnetic film and a recording/reproducing winding 6.
An auxiliary magnetic pole 5 made of a sufficiently thicker magnetic material is placed between the recording body 9 or 1o, or a recording body 9 or 1
A strip-shaped main magnetic pole 7 provided with a recording and reproducing winding 8 is used so that recording and reproducing can be performed only on one side of the magnetic pole. When using these magnetic heads, the above-mentioned 2.
It is known that the recording and reproducing efficiency is improved by using a layered film, and the effect of the high permeability magnetic layer 3 provided between the base body 1 and the perpendicularly magnetized film 2 is attracting attention.
これは高透磁率磁性層３が、記録体１０の構成要素であ
りながら磁気ヘッドの１部分と見なすことができ、それ
が垂直磁化膜２に近接して設けられた効果と考えること
ができる。This can be considered to be an effect of the high permeability magnetic layer 3 being provided close to the perpendicular magnetization film 2, since it can be considered as a part of the magnetic head, although it is a component of the recording body 10.
従って、２層膜を用いた場合の記録再生効率はこの高透
磁率磁性層３の特性によっても影響を受けるので、媒体
作製に当って新たな問題を生じている。Therefore, since the recording and reproducing efficiency when using a two-layer film is also affected by the characteristics of this high permeability magnetic layer 3, a new problem has arisen in producing the medium.
例えば、２層膜を７０ツピニデイスクや磁気ディスクの
様な同心円板状の基体上に形成する場合を考えると、高
透磁率磁性層はスパッタリングや蒸着やメッキ等による
成膜時に誘導磁気異方性によって、通常第３図に示す様
に一軸方向Ｃｙ軸方向）に磁化容易軸１３を有する異方
性を生じる。For example, if we consider the case where a two-layer film is formed on a concentric disk-shaped substrate such as a 70-tupini disk or a magnetic disk, the high magnetic permeability magnetic layer is formed by induced magnetic anisotropy during film formation by sputtering, vapor deposition, plating, etc. , an anisotropy having an easy axis of magnetization 13 in the uniaxial direction (Cy-axis direction) is usually produced as shown in FIG.
その結果、円板１２上の場所によって記録再生効率の違
いを生じる。つまり、記録位置における高透磁率磁性層
の異方性が第３図のＡＢＣに示す様に困難軸方向の場合
、その透磁率は広い周波数領域で高いので、記録再生効
率の向上も顕著であるが、第３図のＢやＤに示す様に容
易軸方向の場合特に高い周波数においては、透磁率が低
下するので記録再生効率もあまり向上しなくガる。その
ため、たとえ垂直磁化膜の特性が円板１２上で、均一で
あっても、第４図に示す様な円板−周における再生出力
１４の変動を生じる。As a result, the recording and reproducing efficiency differs depending on the location on the disk 12. In other words, when the anisotropy of the high magnetic permeability magnetic layer at the recording position is in the difficult axis direction as shown by ABC in Figure 3, the magnetic permeability is high in a wide frequency range, so the improvement in recording and reproducing efficiency is also remarkable. However, as shown in B and D in FIG. 3, in the case of the easy axis direction, especially at high frequencies, the magnetic permeability decreases, so that the recording and reproducing efficiency does not improve much. Therefore, even if the characteristics of the perpendicularly magnetized film are uniform on the disk 12, the reproduction output 14 varies along the circumference of the disk as shown in FIG.
この様な不都合をなくすため、通常は円板状基体１２を
回転させながら高透磁率磁性層３を成膜することによっ
て磁気特性を等方向にする手法がとられるが、この場合
の磁気特性は分散的となりがちである。従って、その透
磁率はあまり高くできないので、記録再生効率の向上も
十分とは言えない０
本発明の目的は以上の様な問題点を解決し、円板全面に
おいて記録再生効率が向上した２層膜から成る磁気記録
体を提供することにある。In order to eliminate such inconveniences, a method is usually adopted in which the high permeability magnetic layer 3 is formed while rotating the disc-shaped substrate 12 to make the magnetic properties uniform. They tend to be decentralized. Therefore, since the magnetic permeability cannot be increased too much, the improvement in recording and reproducing efficiency cannot be said to be sufficient.The purpose of the present invention is to solve the above-mentioned problems, and to provide a two-layer structure with improved recording and reproducing efficiency over the entire surface of the disk. An object of the present invention is to provide a magnetic recording body made of a film.
本発明にかかる垂直磁気記録体は、同心円板状の基体上
に高透磁率磁性層１次いで膜面に垂直な方向に磁化容易
軸を有する磁性層の順に形成して成る垂直磁気記録体に
おいて、前記高透磁率磁性層は、磁化容易軸を前記円板
の半径方向に放射状に有することを特徴とする。A perpendicular magnetic recording body according to the present invention is a perpendicular magnetic recording body in which a high permeability magnetic layer is sequentially formed on a concentric disk-shaped substrate, followed by a magnetic layer having an axis of easy magnetization in a direction perpendicular to the film surface. The high permeability magnetic layer is characterized in that it has an axis of easy magnetization radially in the radial direction of the disk.
又、本発明による垂直磁気記録体の製造方法は前記高透
磁率磁性層成膜時に前記円板状基体の中心から半径方向
に放射状の直流磁界を印加するととを特徴とする。Further, the method for manufacturing a perpendicular magnetic recording body according to the present invention is characterized in that a radial direct current magnetic field is applied in a radial direction from the center of the disc-shaped substrate when forming the high permeability magnetic layer.
次に、本発明の実施例について図面を用いて説明する。Next, embodiments of the present invention will be described using the drawings.
第５図（ａ）（ｂ）は本発明による垂直磁気記録体の特
徴を示した図であり、同心円板状基体１５上に形成され
た高透磁率磁性層３の容易磁化方向１６が、円板１５の
半径方向に放射状になっている。5(a) and 5(b) are diagrams showing the characteristics of the perpendicular magnetic recording body according to the present invention, in which the easy magnetization direction 16 of the high permeability magnetic layer 3 formed on the concentric disc-shaped substrate 15 is circular. It is radial in the radial direction of the plate 15.
次に、この様な高透磁率磁性層３の作製方法を説明する
。第６図はＲＦスパッタリングによる作製方法を模式的
に示したものである。これによれば、ＮｉＦｅ合金から
成るターゲット１７が、ターゲットホルダ１８に固定さ
れ、さらにマツチングボックス２０を介して高周波電源
２１に接続されている。Next, a method for manufacturing such a high permeability magnetic layer 3 will be explained. FIG. 6 schematically shows a manufacturing method using RF sputtering. According to this, a target 17 made of a NiFe alloy is fixed to a target holder 18 and further connected to a high frequency power source 21 via a matching box 20.
一方、同心円板状基体１５を固定したもう一方の電極ｚ
２の下で円板の中心近傍に垂直方向に着磁した永久磁石
２３が配設されている。この永久磁石２３によって第７
図に示す様に前記円板状基体１５には数十エルテッド以
上の直流磁界２４が、半径方向に放射状に印加されてい
る。On the other hand, the other electrode z to which the concentric disk-shaped substrate 15 is fixed
A permanent magnet 23 magnetized perpendicularly is arranged near the center of the disk under the magnet 2 . This permanent magnet 23 causes the seventh
As shown in the figure, a DC magnetic field 24 of tens of elts or more is applied radially to the disk-shaped base 15.
この状態でチャンバー１９内を１０ＴＯｒｒ以下に真空
引きした後、例えば次の条件でス／＜ツタリングを行う
と、誘導磁気異方性によって円板状基体１５上には、こ
の円板の半径方向に放射状の磁化容易軸を有するＮｉＦ
ｅ膜が０．５μｍの厚さに成膜される。After evacuating the inside of the chamber 19 to 10 TOrr or less in this state, for example, when starching is carried out under the following conditions, the induced magnetic anisotropy causes the disk-shaped substrate 15 to be evacuated in the radial direction of the disk. NiF with radial easy axis of magnetization
An e-film is deposited to a thickness of 0.5 μm.
第８図は蒸着による作製法を示したもので、第６図と同
様、円板状基体１５の裏側で円板の中心近傍に、垂直方
向に着磁した永久磁石２３が配設されている。この場合
も円板の半径方向に放射状の直流磁界２４が印加された
状態で、Ｎ１ｃｅの蒸着が行われるので、同様の磁化容
易軸を有するＮｉＦｅ膜が成膜される。FIG. 8 shows a manufacturing method by vapor deposition, and as in FIG. 6, a permanent magnet 23 magnetized in the vertical direction is arranged near the center of the disk on the back side of the disk-shaped substrate 15. . In this case as well, since N1ce is deposited while the radial DC magnetic field 24 is applied in the radial direction of the disk, a NiFe film having a similar axis of easy magnetization is formed.
尚、同心円板状基体１５としては、厚さ数十ミクロンの
ポリエステル、ポリイミド、ポリアミドもしくは厚さ数
ミリメートルのガラス、アルミニウム合金板の上にアル
マイト皮膜金膜けたもの、もしくはアルミニウム合金板
の上にＮｉＰをメッキしたもの等が用いられ、外径は７
００〜２００順内径は１０〜３０朋である。The concentric disk-shaped substrate 15 may be made of polyester, polyimide, or polyamide with a thickness of several tens of microns, glass with a thickness of several millimeters, an aluminum alloy plate with an alumite coating and a gold film, or an aluminum alloy plate with an alumite coating and a gold film, or NiP on an aluminum alloy plate. Plated, etc. are used, and the outer diameter is 7
The inner diameter in order of 00 to 200 is 10 to 30 mm.
以上の様にして形成された高透磁率磁性層３の上に、さ
らにＣｏＣｒ合金やバリウムフェライト等の垂直磁化膜
２を数千〜数ミクロンの厚さにスパッタリング、蒸着等
の成膜技術もしくは塗布技術によって、形成することに
よって本発明の垂直磁気記録体が得られる。この記録体
では円板上の全ての記録位置において、高透磁率磁性層
３の磁気異方性が困難軸となっているので、高い透磁率
が広い周波数領域で実現されている。On top of the high permeability magnetic layer 3 formed as described above, a perpendicularly magnetized film 2 made of CoCr alloy, barium ferrite, etc. is further applied to a thickness of several thousand to several microns using film formation techniques such as sputtering or vapor deposition, or coating. The perpendicular magnetic recording body of the present invention can be obtained by forming the perpendicular magnetic recording body according to the technique. In this recording medium, the magnetic anisotropy of the high permeability magnetic layer 3 is the hard axis at all recording positions on the disk, so high magnetic permeability is achieved over a wide frequency range.
従って、第１図および第２図で示した磁気ヘッドを用い
た時の記録再生効率は、円板上の全ての位置で向上しエ
ンベロープも良好なものとなる。Therefore, when using the magnetic heads shown in FIGS. 1 and 2, the recording and reproducing efficiency is improved at all positions on the disk, and the envelope is also good.
以上、高透磁率磁性層３としては、０．５μｍ厚のＮｉ
Ｆｅ合金についてのみ述べたが、とれに限定されるもの
ではなく、厚みは数千オングストローム−数ミクロンの
範囲で良く、又ＮｉＦｅ系合金以外にＣｏＺｒ系アモル
ファス合金等他の高透磁率磁性材料も同様に適用できる
。叉、磁界発生手段として基体１５の裏に永久磁石２３
を配設する方法についてのみ述べだが、これに限らず円
心円板状基体１５に対して半径方向に放射状の磁界を発
生できるならば、永久磁石の位置及び形状を変えても良
い。As described above, the high permeability magnetic layer 3 is made of Ni with a thickness of 0.5 μm.
Although only the Fe alloy has been described, it is not limited to iron, and the thickness may be in the range of several thousand angstroms to several microns.In addition to NiFe alloys, other high permeability magnetic materials such as CoZr amorphous alloys can also be used. Applicable to Additionally, a permanent magnet 23 is provided on the back of the base 15 as a magnetic field generating means.
Although only the method of arranging the permanent magnets is described above, the position and shape of the permanent magnets may be changed as long as a radial magnetic field can be generated in the radial direction with respect to the circular disk-shaped base 15.
以上述べた様に本発明によれば、同心円板状の全面にお
いて記録再生効率の向上した２層膜から成る垂直磁気記
録体が提供できる。As described above, according to the present invention, it is possible to provide a perpendicular magnetic recording body consisting of a two-layer film with improved recording and reproducing efficiency over the entire surface of a concentric disk shape.
第１図、第２図は垂直磁気記録方式を説明するだめの図
、第３図？ｄ従来例を示す図、第４図は従来例の動作を
示す図、第５図（ａｌｂ）は本発明の実施例を示す図、
第６〜８図は本発明の製造方法を示す図である。
図において、■は基本、２は垂直磁化膜、３は高透磁率
磁性層、４，７は主磁極、５は補助ｉ極、６．８は巻線
、９は単層膜記録体、１ｏは２層膜記録体、１１は磁化
、１２．１５は同心円板状基体、１３゜１６は磁化容易
軸方向、１４１寸再生出力、１７１ｄスパツタターゲツ
ト、１８はターゲットホルダ、１９はスパッタチャンバ
、２０ｉｄマツチングボツクス、２１は高周波電源、２
２は基板電極、２３は永久磁石、２４（ｄ直流磁界、２
５は蒸着装置チャンバ、拠はルツボ、２７は蒸着源を示
す。
代理人弁理士 市原 晋
７１図
７２図
７３図
Ａ
第４図
第５図
２１−６図
７７図
４
７８図Figures 1 and 2 are just diagrams to explain the perpendicular magnetic recording system, and Figure 3? d A diagram showing the conventional example, FIG. 4 is a diagram showing the operation of the conventional example, FIG. 5 (alb) is a diagram showing the embodiment of the present invention,
6 to 8 are diagrams showing the manufacturing method of the present invention. In the figure, ■ is the basic, 2 is the perpendicular magnetization film, 3 is the high permeability magnetic layer, 4 and 7 are the main magnetic poles, 5 is the auxiliary i-pole, 6.8 is the winding, 9 is the single-layer film recording body, 1o is a two-layer film recording body, 11 is magnetization, 12.15 is a concentric disk-shaped substrate, 13° 16 is an axis of easy magnetization, 141 inch reproduction output, 171 d sputter target, 18 is a target holder, 19 is a sputter chamber, 20 id Matching box, 21 is a high frequency power supply, 2
2 is a substrate electrode, 23 is a permanent magnet, 24 (d DC magnetic field, 2
5 is a vapor deposition apparatus chamber, base is a crucible, and 27 is a vapor deposition source. Representative Patent Attorney Susumu Ichihara71Figure 72Figure 73Figure AFigure 4Figure 5Figure 21-6Figure 77Figure 4 78
Claims (2)
面に垂直な方向に磁化容易軸を有する磁性層の順に形成
されて成る垂直磁気記録体において、前記高透磁率磁性
層は、磁化容易軸を前記円板の半径方向に放射状に有す
ることを特徴とする垂直磁気記録体。(1) In a perpendicular magnetic recording body in which a high magnetic permeability magnetic layer is formed on a concentric disk-shaped substrate, and then a magnetic layer having an easy axis of magnetization in a direction perpendicular to the film surface is formed in this order, the high magnetic permeability magnetic layer is . A perpendicular magnetic recording body, characterized in that the axis of easy magnetization is radial in the radial direction of the disk.
性層上に膜面に垂直な方向に磁化容易軸を有する磁性層
を形成する垂直磁気記録体の製造方法において高透磁率
磁性層成膜時に前記円板状基体の中心から半径方向に放
射状の直流磁界を印加することを特徴とする垂直磁気記
録体の製造方法。(2) A method for manufacturing a perpendicular magnetic recording body in which a high magnetic permeability magnetic layer is formed on a concentric disc-shaped substrate, and a magnetic layer having an axis of easy magnetization in a direction perpendicular to the film surface is formed on the magnetic layer. A method for manufacturing a perpendicular magnetic recording body, characterized in that a radial direct current magnetic field is applied in a radial direction from the center of the disc-shaped substrate when forming a magnetic layer.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP16077683A JPS6052919A (en) | 1983-09-01 | 1983-09-01 | Vertical magnetic recording medium and its production |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP16077683A JPS6052919A (en) | 1983-09-01 | 1983-09-01 | Vertical magnetic recording medium and its production |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS6052919A true JPS6052919A (en) | 1985-03-26 |
| JPH0473212B2 JPH0473212B2 (en) | 1992-11-20 |
Family
ID=15722204
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP16077683A Granted JPS6052919A (en) | 1983-09-01 | 1983-09-01 | Vertical magnetic recording medium and its production |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6052919A (en) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6348610A (en) * | 1986-08-15 | 1988-03-01 | Nec Corp | Magnetic recording medium |
| US5176965A (en) * | 1987-10-05 | 1993-01-05 | Digital Equipment Corporation | Magnetic medium for longitudinal recording |
| JPH06342512A (en) * | 1991-09-30 | 1994-12-13 | Victor Co Of Japan Ltd | Perpendicular magnetic recording medium and its production |
| US5765460A (en) * | 1995-12-18 | 1998-06-16 | Wathieu; Patrick | Paper cutter for variable format |
| WO2006082948A1 (en) * | 2005-02-01 | 2006-08-10 | Tohoku University | Perpendicular magnetic recording media, production process thereof, and perpendicular magnetic recording and reproducing apparatus |
| JP2009230826A (en) * | 2008-03-25 | 2009-10-08 | Fujifilm Corp | Magnetic transfer method and magnetic recording medium |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5868226A (en) * | 1981-10-16 | 1983-04-23 | Hitachi Ltd | Magnetic recording medium |
-
1983
- 1983-09-01 JP JP16077683A patent/JPS6052919A/en active Granted
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5868226A (en) * | 1981-10-16 | 1983-04-23 | Hitachi Ltd | Magnetic recording medium |
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6348610A (en) * | 1986-08-15 | 1988-03-01 | Nec Corp | Magnetic recording medium |
| US5176965A (en) * | 1987-10-05 | 1993-01-05 | Digital Equipment Corporation | Magnetic medium for longitudinal recording |
| US5431969A (en) * | 1987-10-05 | 1995-07-11 | Quantum Corporation | Method of making a magnetic medium for longitudinal recording |
| JPH06342512A (en) * | 1991-09-30 | 1994-12-13 | Victor Co Of Japan Ltd | Perpendicular magnetic recording medium and its production |
| US5765460A (en) * | 1995-12-18 | 1998-06-16 | Wathieu; Patrick | Paper cutter for variable format |
| WO2006082948A1 (en) * | 2005-02-01 | 2006-08-10 | Tohoku University | Perpendicular magnetic recording media, production process thereof, and perpendicular magnetic recording and reproducing apparatus |
| JP2006244688A (en) * | 2005-02-01 | 2006-09-14 | Tohoku Univ | Perpendicular magnetic recording medium, production process thereof, and perpendicular magnetic recording and reproducing apparatus |
| US7943248B2 (en) | 2005-02-01 | 2011-05-17 | Tohoku University | Perpendicular magnetic recording media, production process thereof, and perpendicular magnetic recording and reproducing apparatus |
| JP2009230826A (en) * | 2008-03-25 | 2009-10-08 | Fujifilm Corp | Magnetic transfer method and magnetic recording medium |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0473212B2 (en) | 1992-11-20 |
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