JPH10289434A - Magnetic disk and magnetic recordor using the magnetic disk - Google Patents
Magnetic disk and magnetic recordor using the magnetic diskInfo
- Publication number
- JPH10289434A JPH10289434A JP9934397A JP9934397A JPH10289434A JP H10289434 A JPH10289434 A JP H10289434A JP 9934397 A JP9934397 A JP 9934397A JP 9934397 A JP9934397 A JP 9934397A JP H10289434 A JPH10289434 A JP H10289434A
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- Japan
- Prior art keywords
- magnetic
- film
- ferromagnetic
- layer
- recording
- Prior art date
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- Thin Magnetic Films (AREA)
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は高密度化に好適な磁
気ディスクおよびこれを利用した磁気記録装置に関す
る。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic disk suitable for high density recording and a magnetic recording apparatus using the same.
【０００２】[0002]
【従来の技術】従来磁気ディスクに使われる磁性層は、
たとえばデニスミー、エリック ダニエル著マグネティ
ック レコーディング ハンドブック、テクノロジー ア
ンド アプリケーション（マクグローヒル パブリッシン
グ カンパニー、１９９０）に示されているように基板
上に下地層を設け、その上に記録層として強磁性体膜を
積層し、さらに保護膜を積層する。現在主流のこのタイ
プの面内媒体では記録密度の上昇に従い媒体の膜厚を薄
くする必要がある。これは、記録ビット自身が生成する
反磁場によりそのビット形状が破壊されることを抑制す
るためである。2. Description of the Related Art Magnetic layers conventionally used in magnetic disks are:
For example, as shown in Dennis Me, Eric Daniel's Magnetic Recording Handbook, Technology and Applications (McGraw Hill Publishing Company, 1990), an underlayer is provided on a substrate, and a ferromagnetic film is laminated thereon as a recording layer. A protective film is laminated. In this type of in-plane medium, which is currently mainstream, it is necessary to reduce the thickness of the medium as the recording density increases. This is to prevent the bit shape from being destroyed by the demagnetizing field generated by the recording bit itself.
【０００３】また高密度化に従って、媒体ノイズを抑え
るため、媒体を構成する結晶粒を微細化する必要があ
る。媒体が薄膜化し、ビットサイズが微小化すると、１
ビットを構成する磁性体の体積が減少し、熱揺らぎ磁気
余効により、ビット内の磁化が時間とともに減少してし
まう。さらにビット内の結晶粒があるサイズ以下になる
と結晶粒内の磁化が熱のため揺らぎはじめ、キュリー温
度以下でも常磁性的な振る舞いをする超常磁性状態とな
る。Further, as the density increases, it is necessary to make the crystal grains constituting the medium finer in order to suppress medium noise. When the medium becomes thinner and the bit size becomes smaller, 1
The volume of the magnetic material constituting the bit decreases, and the magnetization in the bit decreases with time due to thermal fluctuation magnetic aftereffect. Furthermore, when the crystal grains in the bit become smaller than a certain size, the magnetization in the crystal grains starts to fluctuate due to heat, and becomes a superparamagnetic state that behaves paramagnetically even at a Curie temperature or lower.
【０００４】つまり、面内媒体では、高密度化が進むと
長時間記録情報を保持することがむづかしくなる。That is, as the density of an in-plane medium increases, it becomes difficult to hold recorded information for a long time.
【０００５】[0005]
【発明が解決しようとする課題】本発明は、上記熱揺ら
ぎ磁気余効、および超常磁性を抑え、高密度記録時でも
記録磁化を安定に保持する磁気ディスクおよびこれを利
用した磁気記録装置を提供することにある。SUMMARY OF THE INVENTION The present invention provides a magnetic disk which suppresses the above-mentioned thermal fluctuation magnetic aftereffect and superparamagnetism and stably retains recording magnetization even during high-density recording, and a magnetic recording apparatus using the same. Is to do.
【０００６】[0006]
【課題を解決するための手段】上記課題を解決する磁気
ディスクは磁性層として強磁性体と反強磁性体をそれぞ
れ１層以上使用した多層膜、あるいは強磁性体とフェリ
磁性体をそれぞれ１層以上使用した多層膜とすることで
達成可能となる。The magnetic disk for solving the above-mentioned problems is a multilayer film using at least one ferromagnetic material and one antiferromagnetic material as a magnetic layer, or one ferromagnetic material and one ferrimagnetic material. This can be achieved by using the multilayer film used above.
【０００７】[0007]
【発明の実施の形態】図１（ａ）は本発明に関わる磁気
ディスクの断面の基本的な構成を示す図であり、基板３
上に反強磁性体膜２、強磁性体膜１がそれぞれ１層成膜
され、その上にさらに保護膜４が塗布されている状態を
示す。反強磁性体膜２はネール温度が室温以上であるNi
O、FeMn、NiMn等を使用する。結晶性を制御するため反
強磁性体膜２と基板３との間には下地層を入れてもよ
い。反強磁性体膜２は多結晶薄膜となるようにスパッタ
リング法等で成膜し、強磁性体膜１は通常磁気ディスク
に使用されているCo系合金を使用し、スパッタリング法
等でゼロ磁場中で成膜する。ここで反強磁性体膜２の結
晶粒のサイズが１０ nm 以下となるように成膜条件を制
御する。図はこの媒体に０、１が交互に記録されている
状態を表しており、強磁性体膜１内の矢印は磁化５を表
している。また反強磁性体膜２内の矢印は内部の磁気モ
ーメント６を模式的に表したものである。強磁性体膜１
と反強磁性体膜２との界面７では、交換相互作用が働
き、界面７に接する強磁性体膜１内の磁気モーメントと
反強磁性体膜２の磁気モーメントとが平行になろうとす
る（交換異方性）。反強磁性体膜２が単結晶であり、界
面が平坦であれば、界面上での磁気モーメントの向きは
１方向になる場合があり、交換異方性が大きくなる。し
かし、反強磁性体膜２は多結晶であり、界面はミクロス
コピックには平坦ではないため、最表面のある方向を向
いた磁気モーメントとそれと反対方向を向いた磁気モー
メントの数はほぼ同数となる。このためマクロな交換異
方性は現れず、磁性膜のヒステリシスループはほぼ原点
対称となる。しかし、界面では交換相互作用が以前とし
て働いているため、強磁性体膜１の保磁力は、強磁性体
膜単独のときと比べ大きくなる。FIG. 1A is a diagram showing a basic configuration of a cross section of a magnetic disk according to the present invention.
This shows a state in which an antiferromagnetic material film 2 and a ferromagnetic material film 1 are each formed as a single layer, and a protective film 4 is further applied thereon. The antiferromagnetic film 2 is made of Ni having a Neel temperature of room temperature or higher.
O, FeMn, NiMn, etc. are used. An underlayer may be provided between the antiferromagnetic film 2 and the substrate 3 to control the crystallinity. The antiferromagnetic film 2 is formed by a sputtering method or the like so as to become a polycrystalline thin film. The ferromagnetic film 1 is made of a Co-based alloy usually used for a magnetic disk, and is subjected to a zero magnetic field by a sputtering method or the like. To form a film. Here, the film forming conditions are controlled so that the crystal grain size of the antiferromagnetic film 2 is 10 nm or less. The figure shows a state in which 0 and 1 are alternately recorded on this medium, and the arrow in the ferromagnetic film 1 indicates magnetization 5. Arrows in the antiferromagnetic film 2 schematically represent the internal magnetic moment 6. Ferromagnetic film 1
At the interface 7 between the ferromagnetic film 2 and the antiferromagnetic film 2, an exchange interaction acts so that the magnetic moment in the ferromagnetic film 1 in contact with the interface 7 and the magnetic moment of the antiferromagnetic film 2 try to be parallel ( Exchange anisotropy). If the antiferromagnetic film 2 is a single crystal and the interface is flat, the direction of the magnetic moment on the interface may be one direction, and the exchange anisotropy increases. However, since the antiferromagnetic film 2 is polycrystalline and the interface is not flat in microscopic terms, the number of magnetic moments directed in a certain direction on the outermost surface and the opposite direction is almost the same. Become. Therefore, macro exchange anisotropy does not appear, and the hysteresis loop of the magnetic film is almost symmetrical with the origin. However, at the interface, since the exchange interaction works as before, the coercive force of the ferromagnetic film 1 is larger than that of the ferromagnetic film alone.
【０００８】ＧＭＲヘッドへの応用のために、上記と同
様の反強磁性体膜上に強磁性体膜を成膜した系が研究さ
れている。例えば強磁性体として透磁率の高いパーマロ
イ薄膜を、反強磁性体としてＮｉＯを使用してチーワン
ライらがアイトリプルイートランザクションズ オン
マグネティックス、３１巻、６号、１９９５年、２６０
９ページから２６１１ページに報告している。図１
（ｂ）にＧＭＲヘッドの断面構造の模式図を示す。図に
おいて、３００は基板であり、基板３００上に反強磁性
体膜２００および強磁性体膜１００がそれぞれ１層成膜
される。その上にさらに非磁性体膜８００および強磁性
体膜９００がそれぞれ１層成膜される。図１（ａ）、
（ｂ）を対比してみると、基板３００上に反強磁性体膜
２００および強磁性体膜１００がそれぞれ１層成膜され
た構造は外見上同じ構造であるが、ＧＭＲヘッドで使用
される反強磁性体膜２００はその上に成膜した強磁性体
膜１００の磁化を一方向に向け、これをピン止めするた
めに使用される。これは強磁性体膜１００のヒステリシ
スループを磁場軸方向にシフトすることに対応し、その
シフト量を大きくすることが重要な課題となっている。
また保磁力はできるだけ小さくするのが望ましい。これ
に対し、本発明においては、反強磁性体膜２はその上に
成膜した強磁性体膜１の保磁力を大きくする目的で使用
されるものであって、本質的に異なるものである。な
お、ＧＭＲのヘッドでは、強磁性体膜９００の磁化の方
向は、強磁性体膜１００のそれに対して直角方向（図の
例では紙面の裏側に向かう方向）である。For application to a GMR head, a system in which a ferromagnetic film is formed on the same antiferromagnetic film as described above has been studied. For example, using a permalloy thin film with high magnetic permeability as a ferromagnetic material and NiO as an antiferromagnetic material, Qi Wan Rai et al.
Magnetics, Vol. 31, No. 6, 1995, 260
Reports from pages 9 to 2611. FIG.
FIG. 2B is a schematic diagram of a cross-sectional structure of the GMR head. In the figure, reference numeral 300 denotes a substrate on which one antiferromagnetic film 200 and one ferromagnetic film 100 are formed. A non-magnetic film 800 and a ferromagnetic film 900 are further formed thereon, respectively. FIG. 1 (a),
Compared with (b), the structure in which the antiferromagnetic film 200 and the ferromagnetic film 100 are each formed on the substrate 300 is the same in appearance, but is used in a GMR head. The antiferromagnetic film 200 is used to direct the magnetization of the ferromagnetic film 100 formed thereon in one direction and pin it. This corresponds to shifting the hysteresis loop of the ferromagnetic film 100 in the direction of the magnetic field axis, and increasing the shift amount is an important issue.
It is desirable that the coercive force be as small as possible. On the other hand, in the present invention, the antiferromagnetic film 2 is used for the purpose of increasing the coercive force of the ferromagnetic film 1 formed thereon, and is essentially different. . In the GMR head, the direction of magnetization of the ferromagnetic film 900 is a direction perpendicular to that of the ferromagnetic film 100 (in the example in the drawing, the direction toward the back of the paper).
【０００９】図２（ａ）は前述した磁気ディスク５０と
記録再生用の磁気ヘッド９およびレーザー光線８との関
係を断面図で示す。記録に際しては、書き込むビット近
傍をレーザー光線８によってネール温度TN付近まで加熱
し、強磁性体膜１と反強磁性体膜２の間に作用する交換
相互作用を十分小さくする。ここでは基板３は透明とし
ており、レーザー光線８を基板を通して反強磁性体膜２
に照射している。反強磁性体膜２の加熱された部分は常
磁性状態となり、磁気モーメントのオーダーが消失し、
これに伴い交換異方性も消失する。この部分の反強磁性
体膜２に隣接する強磁性体膜１に磁気ヘッド９からの磁
場でビット情報を書き込む。交換異方性が消失している
ので磁気ヘッド９の書き込み磁場は比較的小さなもので
よい。磁化反転後、反強磁性体膜２がTN以下になったと
き、反強磁性体の界面７の磁気モーメントは強磁性体膜
１の磁気モーメントに引きずられ平行に揃い、以下内部
の磁気モーメントも交互に配列することになる。これに
より、図２（ｂ）に示すように交換異方性が回復し記録
ビットは安定化する。図２（ｂ）と図1とを対照して分
かるように、図の右側2番目のビットが書き換えられて
いる。再生動作は通常の磁気記録装置と同様であり、イ
ンダクティブヘッド、MRヘッド等の磁気ヘッドにより媒
体からの漏れ磁場を検出してビット情報とする。FIG. 2A is a sectional view showing the relationship between the magnetic disk 50, the recording / reproducing magnetic head 9 and the laser beam 8. At the time of recording, the vicinity of the bit to be written is heated to near the Neel temperature TN by the laser beam 8 to sufficiently reduce the exchange interaction acting between the ferromagnetic film 1 and the antiferromagnetic film 2. Here, the substrate 3 is made transparent, and the laser beam 8 is passed through the substrate to form the antiferromagnetic film 2.
Irradiation. The heated portion of the antiferromagnetic film 2 becomes paramagnetic and the order of the magnetic moment disappears,
With this, the exchange anisotropy also disappears. Bit information is written to the ferromagnetic film 1 adjacent to the antiferromagnetic film 2 in this portion by the magnetic field from the magnetic head 9. Since the exchange anisotropy has disappeared, the writing magnetic field of the magnetic head 9 may be relatively small. After the magnetization reversal, when the antiferromagnetic material film 2 becomes T N or less, the magnetic moment at the interface 7 of the antiferromagnetic material is dragged by the magnetic moment of the ferromagnetic material film 1 and is aligned in parallel. Are also arranged alternately. As a result, as shown in FIG. 2B, the exchange anisotropy is recovered, and the recording bit is stabilized. As can be seen by comparing FIG. 2B and FIG. 1, the second bit on the right side of the figure is rewritten. The reproducing operation is the same as that of a normal magnetic recording device, and a magnetic head such as an inductive head or an MR head detects a leakage magnetic field from a medium to generate bit information.
【００１０】次に強磁性体と補償温度Tcompの存在する
フェリ磁性体を使用する場合を示す。まず図３（ａ）に
強磁性体とフェリ磁性体の磁化の温度変化を模式的に示
す。曲線１０、１１はそれぞれ強磁性体、フェリ磁性体
の磁化曲線である。強磁性体のキュリー温度Tc1はフェ
リ磁性体のキュリー温度Tc2より大きいものとする。こ
こでフェリ磁性体としてTbFeCo等の希土類金属と遷移金
属で構成されたものを、強磁性体としてCo合金等の遷移
金属合金を使用する。フェリ磁性体は遷移金属の磁化と
希土類金属の磁化が逆方向を向いている。このときT
comp以下では遷移金属の磁化が希土類金属の磁化より小
さく、Tcomp以上では大きくなる。Next, a case will be described in which a ferrimagnetic material and a ferrimagnetic material having a compensation temperature T comp are used. First, FIG. 3A schematically shows the temperature change of the magnetization of the ferromagnetic material and the ferrimagnetic material. Curves 10 and 11 are magnetization curves of a ferromagnetic material and a ferrimagnetic material, respectively. Curie temperature T c1 of the ferromagnetic body is made larger than the Curie temperature T c2 of the ferromagnetic body. Here, a ferrimagnetic material composed of a rare earth metal such as TbFeCo and a transition metal is used, and a ferromagnetic material is a transition metal alloy such as a Co alloy. In the ferrimagnetic material, the magnetization of the transition metal and the magnetization of the rare earth metal are in opposite directions. Then T
Below comp , the magnetization of the transition metal is smaller than that of the rare earth metal, and above T comp , it becomes larger.
【００１１】図３（ｂ）は磁気ディスクの断面を表して
おり、図１の反強磁性体膜２をフェリ磁性体膜１２に置
き換えた構造となっている。ここで、強磁性体膜１、フ
ェリ磁性体膜１２は垂直磁気異方性を持つと仮定した。
強磁性体膜１内の矢印は記録ビットの磁化５を示す。ま
たフェリ磁性体膜１２内の細い矢印、および太い矢印は
それぞれ遷移金属と希土類金属のそれぞれの磁気モーメ
ント１３、１４を模式的に示したものである。遷移金属
の磁性を担う3d電子は、希土類金属の磁性を担う4f電子
より空間的に拡がっているので、界面７では遷移金属の
磁気モーメント１３が強磁性体膜１の遷移金属の磁気モ
ーメント（磁化５の源）と相互作用し、図３（ｂ）の左
側に示すようにそれらの向きを揃える。このとき希土類
金属を含んだフェリ磁性体は異方性が大きいので、界面
での相互作用を通して強磁性体の記録ビットを安定化さ
せることになる。今Tcompを室温付近、あるいはTcomp <
室温 < Tc2とすると、図３（ａ）からわかるように、フ
ェリ磁性体膜１２の磁化はほぼゼロ、あるいはある値を
持つ。前者の場合フェリ磁性体膜１２は磁化５に静磁的
には影響を与えない。また後者の場合、磁化は強磁性体
１の磁化５と同方向なので強磁性体１単独の場合より静
磁エネルギー的に安定となる。さらにこの場合、漏れ磁
場は磁化５単独より大きくなり、再生時のS/Nを向上さ
せる。FIG. 3B shows a cross section of the magnetic disk, which has a structure in which the antiferromagnetic film 2 of FIG. Here, it is assumed that the ferromagnetic film 1 and the ferrimagnetic film 12 have perpendicular magnetic anisotropy.
The arrow in the ferromagnetic film 1 indicates the magnetization 5 of the recording bit. Thin arrows and thick arrows in the ferrimagnetic film 12 schematically show the magnetic moments 13 and 14 of the transition metal and the rare earth metal, respectively. Since the 3d electrons that carry the magnetism of the transition metal are more spatially spread than the 4f electrons that carry the magnetism of the rare earth metal, the magnetic moment 13 of the transition metal at the interface 7 changes the magnetic moment (magnetization) of the transition metal of the ferromagnetic film 1. 5 source) and align them as shown on the left side of FIG. 3 (b). At this time, since the ferrimagnetic material containing the rare earth metal has a large anisotropy, the recording bit of the ferromagnetic material is stabilized through the interaction at the interface. Now let T comp near room temperature or T comp <
Assuming that the room temperature is smaller than Tc2, as can be seen from FIG. 3A, the magnetization of the ferrimagnetic film 12 is almost zero or has a certain value. In the former case, the ferrimagnetic film 12 does not magnetostatically affect the magnetization 5. In the latter case, the magnetization is in the same direction as the magnetization 5 of the ferromagnetic material 1, so that the magnetostatic energy is more stable than when the ferromagnetic material 1 is used alone. Further, in this case, the leakage magnetic field is larger than the magnetization 5 alone, and the S / N during reproduction is improved.
【００１２】記録時は、図３（ｃ）に示すように図２
（ａ）と同様透明基板３の下方より、レーザー光線８を
照射してフェリ磁性体１２を加熱、Tc2付近、あるいは
それ以上とする。フェリ磁性体膜１２の磁気異方性は十
分小さく、あるいはゼロとなるので、磁気ヘッド９で磁
化５を比較的簡単に反転することが可能となる。再生時
はインダクティブヘッド、MRヘッド等の磁気ヘッドによ
り媒体からの漏れ磁場を検出してビット情報とする。T
compを室温付近に設定した場合、上述したようにレーザ
ー光線８でフェリ磁性体膜１２をTcomp以上Tc2以下に加
熱することによってビットからの漏れ磁場を増大させ、
再生信号のS/Nを向上させることも可能である。At the time of recording, as shown in FIG.
As in (a), the ferrimagnetic material 12 is heated by irradiating a laser beam 8 from below the transparent substrate 3 to near Tc2 or higher. Since the magnetic anisotropy of the ferrimagnetic film 12 is sufficiently small or zero, the magnetization 5 can be relatively easily reversed by the magnetic head 9. At the time of reproduction, a magnetic head such as an inductive head or an MR head detects a leakage magnetic field from the medium and converts it into bit information. T
If the comp set to around room temperature, increasing the leakage magnetic field from the bit by heating the ferrimagnetic material film 12 above T comp T c2 following laser 8 as described above,
It is also possible to improve the S / N of the reproduction signal.
【００１３】以上、強磁性体膜１と反強磁性体膜２、あ
るいはフェリ磁性体膜１２の２層膜で説明したが、多層
膜でも同様である。Although the above description has been made with reference to the two-layer film of the ferromagnetic film 1 and the antiferromagnetic film 2, or the ferrimagnetic film 12, the same applies to a multilayer film.
【００１４】実施例１ 本発明の磁気ディスクの実施例を図４により説明する。
図４は断面を表している。ガラス基板１５上に直接反強
磁性体NiO１６をスパッタ法で２０nm 成膜し、その後強
磁性体であるCoTaZr１７をスパッタ法で５０nm 成膜
し、さらに保護膜としてカーボン膜を成膜する。NiOの
ネール温度は約２５０度Cである。記録再生動作は通常
の磁気記録装置と同様であり、インダクティブヘッドに
よって記録を行い、インダクティブヘッドあるいはMRヘ
ッド等によって媒体からの漏れ磁場を検出してビット情
報とする。Embodiment 1 An embodiment of a magnetic disk according to the present invention will be described with reference to FIG.
FIG. 4 shows a cross section. An antiferromagnetic material NiO 16 is formed directly on the glass substrate 15 by sputtering to a thickness of 20 nm, then a ferromagnetic material CoTaZr 17 is formed to a thickness of 50 nm by sputtering, and a carbon film is formed as a protective film. The Neel temperature of NiO is about 250 ° C. The recording / reproducing operation is the same as that of a normal magnetic recording apparatus. Recording is performed by an inductive head, and a leakage magnetic field from a medium is detected by an inductive head or an MR head to generate bit information.
【００１５】実施例２ 本発明の記録装置の実施例を図５により説明する。図５
は装置の断面を表している。磁気ディスク１８、再生用
磁気ヘッド・記録用磁気ヘッドを組み込んだ磁気ヘッド
部１９、スライダー２０、磁気ヘッド用アーム２１、駆
動系２２、半導体レーザーと光学系を組み込んだ半導体
レーザーヘッド２３、半導体レーザーヘッド用アーム２
４より構成されている。ここでは磁気ディスク駆動系、
電気回路系、支持具等は省いている。磁気ディスク１８
の上面には保護膜、強磁性体膜、反強磁性体膜、あるい
はフェリ磁性体膜が積層されている。再生は通常の磁気
記録装置と同様に再生用磁気ヘッドによって媒体からの
漏れ磁場を検出してビット情報とする。Embodiment 2 An embodiment of the recording apparatus of the present invention will be described with reference to FIG. FIG.
Represents the cross section of the device. Magnetic disk 18, magnetic head unit 19 incorporating a reproducing magnetic head / recording magnetic head, slider 20, arm 21 for magnetic head, drive system 22, semiconductor laser head 23 incorporating a semiconductor laser and an optical system, semiconductor laser head Arm 2
4. Here, the magnetic disk drive system,
Electrical circuits, supports, etc. are omitted. Magnetic disk 18
A protective film, a ferromagnetic film, an antiferromagnetic film, or a ferrimagnetic film is laminated on the upper surface of the substrate. For reproduction, a leakage magnetic field from the medium is detected by a reproducing magnetic head and converted into bit information as in a normal magnetic recording device.
【００１６】記録時は以下のような動作となる。まず磁
気ヘッド部１９、半導体レーザーヘッド２３を駆動系２
２で所定の位置まで移動させる。半導体レーザーヘッド
２３内の半導体レーザーから照射されたレーザー光線２
５は光学系によって反強磁性体膜に収束され、反強磁性
体膜はネール点TN付近、あるいはそれ以上に加熱され
る。これと同時に記録用ヘッドを作動させ、ヘッドから
の漏れ磁場で強磁性体膜の微小領域を磁化させる。以上
の動作を磁気ディスク１８の回転に従って順次行い一連
の情報を磁気記録する。At the time of recording, the operation is as follows. First, the magnetic head unit 19 and the semiconductor laser head 23 are connected to the drive system 2.
2 to move to a predetermined position. Laser beam 2 emitted from semiconductor laser in semiconductor laser head 23
5 is converged on the antiferromagnetic film by the optical system, and the antiferromagnetic film is heated to near the Neel point TN or higher. At the same time, the recording head is operated to magnetize a minute region of the ferromagnetic film with a leakage magnetic field from the head. The above operations are sequentially performed according to the rotation of the magnetic disk 18 to magnetically record a series of information.
【００１７】反強磁性体膜の代わりにフェリ磁性体膜を
使用する場合も同様である。ただし、さきにも述べたよ
うに、再生時フェリ磁性体をTcomp以上Tc2以下に加熱す
る場合、記録時と同様にレーザー光線で加熱し再生動作
を行う。このときレーザー光線のパワーは強度、あるい
は時間で制御し、最適値にする。The same applies when a ferrimagnetic film is used in place of the antiferromagnetic film. However, as mentioned earlier, when heating the playback ferrimagnetic material below T comp than T c2, performs heating playback operation with laser beam in the same manner as in the recording. At this time, the power of the laser beam is controlled by the intensity or the time to make it an optimum value.
【００１８】以上、強磁性体膜と反強磁性体膜、あるい
はフェリ磁性体膜の２層膜で説明したが、多層膜でも同
様である。Although the above description has been made with reference to a two-layer film of a ferromagnetic film and an antiferromagnetic film, or a ferrimagnetic film, the same applies to a multilayer film.
【００１９】実施例３ 本発明の磁気記録装置の他の実施例を図６により説明す
る。図６はヘッド部分の断面を表している。基板２６、
保護膜、強磁性体膜、反強磁性体膜、あるいはフェリ磁
性体膜で構成された媒体部２７、再生用磁気ヘッド・記
録用磁気ヘッドを組み込んだ磁気ヘッド部１９、スライ
ダー２０、磁気ヘッド用アーム２１、半導体レーザー２
８、ミラー２９、レンズ３０、ハウジング３１、アーム
３２より構成されている。ここでは駆動系、電気回路
系、支持具等は省いている。半導体レーザー２８、ミラ
ー２９、レンズ３０はハウジング３１に固定されてお
り、このハウジング３１はアーム３２に固定されてい
る。磁気ヘッド部１９はレンズ３０、および媒体部２７
の近傍に配置する。Embodiment 3 Another embodiment of the magnetic recording apparatus of the present invention will be described with reference to FIG. FIG. 6 shows a cross section of the head portion. Substrate 26,
A medium unit 27 made of a protective film, a ferromagnetic film, an antiferromagnetic film, or a ferrimagnetic film, a magnetic head unit 19 incorporating a reproducing magnetic head and a recording magnetic head, a slider 20, and a magnetic head unit. Arm 21, semiconductor laser 2
8, a mirror 29, a lens 30, a housing 31, and an arm 32. Here, a drive system, an electric circuit system, a support, and the like are omitted. The semiconductor laser 28, the mirror 29, and the lens 30 are fixed to a housing 31, and the housing 31 is fixed to an arm 32. The magnetic head section 19 includes a lens 30 and a medium section 27.
Is placed in the vicinity of.
【００２０】半導体レーザー２８から照射されたレーザ
ー光線３３はミラー２９で反射されレンズ３０に入射す
る。レンズ３０は凸レンズの一部分であり、レーザー光
線３３は媒体部２７内の反強磁性体膜、あるいはフェリ
磁性体膜に収束される。磁気ヘッド部１９はレーザー光
線３３の収束位置の直上に配置するように位置決めす
る。記録・再生は実施例２と同様である。A laser beam 33 emitted from a semiconductor laser 28 is reflected by a mirror 29 and enters a lens 30. The lens 30 is a part of a convex lens, and the laser beam 33 is focused on an antiferromagnetic film or a ferrimagnetic film in the medium section 27. The magnetic head section 19 is positioned so as to be located immediately above the convergence position of the laser beam 33. Recording and reproduction are the same as in the second embodiment.
【００２１】以上、強磁性体膜と反強磁性体膜、あるい
はフェリ磁性体膜の２層膜で説明したが、多層膜でも同
様である。Although the above description has been made with reference to a two-layer film of a ferromagnetic film and an antiferromagnetic film, or a ferrimagnetic film, the same applies to a multilayer film.
【００２２】実施例４ 本発明の磁気記録装置の他の実施例を図７により説明す
る。図７はヘッド部分の断面を表している。図７は磁気
ヘッド、および磁気ディスクの断面を表している。磁気
ディスクは基板２６、保護膜、強磁性体膜、反強磁性体
膜、あるいはフェリ磁性体膜で構成された媒体部２７で
構成されている。磁気ヘッドはポールピース３４、コイ
ル３５、磁場検出部３６、磁気シールド３７、ヘッド保
持部３８、光ファイバー３９、スライダー２０、磁気ヘ
ッド用アーム２１より構成されている。ここで、ポール
ピース３４、コイル３５で記録用ヘッドを構成し、磁場
検出部３６、磁気シールド３７で再生用ヘッドを構成し
ている。また両者は磁気ヘッド保持部３８に固定されて
いる。光ファイバー３９は、その先端部をポールピース
３４間に入るように配置する。磁気ヘッド保持部３８は
スライダー２０に固定されており、スライダー２０は磁
気ヘッド用アーム２１に固定されている。ここでは駆動
系、電気回路系、支持具等は省いている。Embodiment 4 Another embodiment of the magnetic recording apparatus of the present invention will be described with reference to FIG. FIG. 7 shows a cross section of the head portion. FIG. 7 shows a cross section of a magnetic head and a magnetic disk. The magnetic disk includes a substrate 26, a protective film, a ferromagnetic film, an antiferromagnetic film, or a medium unit 27 formed of a ferrimagnetic film. The magnetic head includes a pole piece 34, a coil 35, a magnetic field detection unit 36, a magnetic shield 37, a head holding unit 38, an optical fiber 39, a slider 20, and a magnetic head arm 21. Here, the pole head 34 and the coil 35 constitute a recording head, and the magnetic field detecting unit 36 and the magnetic shield 37 constitute a reproducing head. Both are fixed to the magnetic head holder 38. The optical fiber 39 is disposed such that the tip end thereof is located between the pole pieces 34. The magnetic head holding section 38 is fixed to the slider 20, and the slider 20 is fixed to the magnetic head arm 21. Here, a drive system, an electric circuit system, a support, and the like are omitted.
【００２３】反強磁性体膜、あるいはフェリ磁性体膜を
加熱する場合、レーザー光線を光ファイバー３９でポー
ルピース３４直下に導き、矢印で示すように、媒体へ照
射することで可能となる。記録・再生動作は実施例２と
同じである。When the antiferromagnetic film or the ferrimagnetic film is heated, a laser beam can be guided under the pole piece 34 by the optical fiber 39 and irradiated on the medium as shown by an arrow. The recording / reproducing operation is the same as in the second embodiment.
【００２４】以上、強磁性体膜と反強磁性体膜、あるい
はフェリ磁性体膜の２層膜で説明したが、多層膜でも同
様である。Although the above description has been made with reference to a two-layer film of a ferromagnetic film and an antiferromagnetic film, or a ferrimagnetic film, the same applies to a multilayer film.
【００２５】実施例５ 本発明の磁気記録装置の他の実施例を図８により説明す
る。図８はヘッド部分の断面を表している。図８は磁気
ヘッド、および磁気ディスクの断面を表しており、実施
例４（図７）に示した磁気ディスクの光ファイバー３９
を高抵抗体薄膜４０で置き換えたものである。その他の
要素は同じであるので符合および説明を省略した。反強
磁性体膜、あるいはフェリ磁性体膜を加熱する場合、高
抵抗体薄膜４０を通電加熱し、ポールピース直下の媒体
を輻射で加熱する。記録・再生動作は実施例２と同じで
ある。Embodiment 5 Another embodiment of the magnetic recording apparatus according to the present invention will be described with reference to FIG. FIG. 8 shows a cross section of the head portion. FIG. 8 shows a cross section of the magnetic head and the magnetic disk, and shows the optical fiber 39 of the magnetic disk shown in the fourth embodiment (FIG. 7).
Is replaced by a high-resistance thin film 40. Since the other elements are the same, the symbols and explanations are omitted. When heating the antiferromagnetic film or the ferrimagnetic film, the high-resistance thin film 40 is heated by energization, and the medium immediately below the pole piece is heated by radiation. The recording / reproducing operation is the same as in the second embodiment.
【００２６】以上、強磁性体膜と反強磁性体膜、あるい
はフェリ磁性体膜の２層膜で説明したが、多層膜でも同
様である。Although the above description has been made with reference to a two-layer film of a ferromagnetic film and an antiferromagnetic film, or a ferrimagnetic film, the same applies to a multilayer film.
【００２７】実施例６ 本発明の磁気ディスクの他の実施例を図９により説明す
る。図９（a）は磁気ディスクの断面を表しており、磁
気ディスクは透明基板３、アレイ状に基板上に配置した
強磁性体４１、強磁性体間を埋める反強磁性体４２、保
護膜４より構成されている。ここで反強磁性体４２で孤
立させられた個々の強磁性体４１が、記録の単位となっ
ているので、この磁気ディスクは量子磁気ディスクと呼
ぶことができる。Embodiment 6 Another embodiment of the magnetic disk according to the present invention will be described with reference to FIG. FIG. 9A shows a cross section of a magnetic disk. The magnetic disk includes a transparent substrate 3, a ferromagnetic material 41 arranged on the substrate in an array, an antiferromagnetic material 42 filling the space between the ferromagnetic materials, and a protective film 4. It is composed of Here, since each ferromagnetic material 41 isolated by the antiferromagnetic material 42 is a unit of recording, this magnetic disk can be called a quantum magnetic disk.
【００２８】前述したように強磁性体４１と反強磁性体
４２の界面には相互作用が働き、強磁性体４１内の磁化
５と反強磁性体４２内の磁気モーメント６が平行とな
り、磁化５は安定化される。記録動作は実施例１、２と
同様であり、図９（ｂ）、（c）で説明する。図９
（ｂ）は書き込み時の磁気ディスクの断面を表したもの
である。レーザー光線８で強磁性体４１に隣接する反強
磁性体４２の界面４３近傍がネール温度TN以上になるよ
うに加熱する。このとき磁化５は相互作用が消失するた
め、磁気ヘッド９からの比較的小さな磁場でビット情報
を書き込むが可能となる。書き込み直後、反強磁性体４
２がTN以下になったとき、界面４３の磁気モーメントは
強磁性体４１の磁気モーメントに引きずられ平行に揃
い、以下内部の磁気モーメントも交互に配列することに
なる。これにより、図９（ｃ）に示すように相互作用が
回復し記録ビットは安定化する。本実施例の反強磁性体
４２をフェリ磁性体で置き換えたものも、同様に動作す
る。As described above, an interaction acts on the interface between the ferromagnetic material 41 and the antiferromagnetic material 42, and the magnetization 5 in the ferromagnetic material 41 and the magnetic moment 6 in the antiferromagnetic material 42 become parallel, 5 is stabilized. The recording operation is the same as in the first and second embodiments, and will be described with reference to FIGS. FIG.
(B) shows a cross section of the magnetic disk at the time of writing. The laser beam 8 is heated so that the vicinity of the interface 43 of the antiferromagnetic material 42 adjacent to the ferromagnetic material 41 becomes higher than the Neel temperature T N. At this time, since the interaction of the magnetization 5 disappears, bit information can be written with a relatively small magnetic field from the magnetic head 9. Immediately after writing, antiferromagnetic material 4
When 2 becomes equal to or less than T N , the magnetic moment of the interface 43 is dragged by the magnetic moment of the ferromagnetic material 41 and is aligned in parallel, and the internal magnetic moments are alternately arranged below. As a result, the interaction is restored as shown in FIG. 9C, and the recording bit is stabilized. A device in which the antiferromagnetic material 42 of this embodiment is replaced with a ferrimagnetic material operates in the same manner.
【００２９】その他の実施例 図１０、１１に強磁性体をアレイ状に配置したものを示
す。これらは、基板４６に反強磁性体４５、あるいはフ
ェリ磁性体４８、強磁性体４４を積層し、アレイ状に整
形したものである。各磁区の間は非磁性材料４７で区分
される。ここで、保護膜は省略している。これらは強磁
性体膜と反強磁性体膜、あるいはフェリ磁性体膜の２層
膜で説明したが、多層膜でも同様である。Other Embodiments FIGS. 10 and 11 show ferromagnetic materials arranged in an array. These are obtained by laminating an antiferromagnetic material 45 or a ferrimagnetic material 48 and a ferromagnetic material 44 on a substrate 46 and shaping them into an array. Each magnetic domain is separated by a non-magnetic material 47. Here, the protective film is omitted. These are described as a two-layer film of a ferromagnetic film and an antiferromagnetic film, or a ferrimagnetic film, but the same applies to a multilayer film.
【００３０】[0030]
【発明の効果】本発明によれば、熱揺らぎ磁気余効、お
よび超常磁性を抑え、高密度記録時でも記録磁化を安定
化させることが可能となり、面内磁気記録、垂直磁気記
録の高密度化が実現できる。According to the present invention, it is possible to suppress the thermal fluctuation magnetic after-effect and superparamagnetism and to stabilize the recording magnetization even at the time of high-density recording. Can be realized.
【図１】（ａ）は本発明に関わる磁気ディスクの断面の
基本的な構成を示す図。（ｂ）はＧＭＲヘッドの断面構
造の模式図を示す図。FIG. 1A is a diagram showing a basic configuration of a cross section of a magnetic disk according to the present invention. (B) is a diagram showing a schematic diagram of a cross-sectional structure of the GMR head.
【図２】（ａ）は前述した磁気ディスク５０と記録再生
用の磁気ヘッド９およびレーザー光線８との関係を示す
断面図。（ｂ）は書き込み後の磁気ディスクの記録状態
を示す断面図。FIG. 2A is a cross-sectional view showing a relationship between the magnetic disk 50 described above, a recording / reproducing magnetic head 9 and a laser beam 8; FIG. 3B is a cross-sectional view illustrating a recording state of the magnetic disk after writing.
【図３】（ａ）は強磁性体とフェリ磁性体の磁化の温度
変化を示す模式図、（ｂ）は磁気ディスクの記録状態を
示す断面図、（ｃ）は書き込み時の磁気ディスクの記録
状態の変化を示す断面図。3A is a schematic diagram showing a temperature change of magnetization of a ferromagnetic material and a ferrimagnetic material, FIG. 3B is a cross-sectional view showing a recording state of a magnetic disk, and FIG. Sectional drawing which shows a change of a state.
【図４】本発明の実施例の磁気ディスクを示す断面図。FIG. 4 is a sectional view showing a magnetic disk according to an embodiment of the present invention.
【図５】本発明の記録装置の概要の実施例を示す断面
図。FIG. 5 is a sectional view showing an embodiment of the outline of the recording apparatus of the present invention.
【図６】本発明の磁気記録装置の他の実施例のヘッド部
分を示す断面図。FIG. 6 is a sectional view showing a head portion of another embodiment of the magnetic recording apparatus of the present invention.
【図７】本発明の磁気記録装置の他の実施例のヘッド部
分を示す断面図。FIG. 7 is a sectional view showing a head portion of another embodiment of the magnetic recording apparatus of the present invention.
【図８】本発明の磁気記録装置の他の実施例のヘッド部
分を示す断面図。FIG. 8 is a sectional view showing a head portion of another embodiment of the magnetic recording apparatus of the present invention.
【図９】（ａ）は本発明の磁気ディスクのの他の実施例
を示す断面図、（ｂ）は書き込み時の磁気ディスクの記
録状態の変化を示す断面図、（ｃ）は磁気ディスクの記
録状態を示す断面図。9A is a cross-sectional view illustrating another embodiment of the magnetic disk of the present invention, FIG. 9B is a cross-sectional view illustrating a change in the recording state of the magnetic disk during writing, and FIG. Sectional drawing which shows a recording state.
【図１０】本発明の他の実施例の磁気ディスクを示す断
面図。FIG. 10 is a sectional view showing a magnetic disk according to another embodiment of the present invention.
【図１１】本発明の他の実施例の磁気ディスクを示す断
面図。FIG. 11 is a sectional view showing a magnetic disk according to another embodiment of the present invention.
１，１００，９００：強磁性体膜、２，２００：反強磁
性体膜、３，３００：基板、４：保護膜、５：磁化、
６：磁気モーメント、７：界面、８：レーザー光線、
９：磁気ヘッド、１０：磁化曲線、１１：磁化曲線、１
２：フェリ磁性体膜、１３：磁気モーメント、１４：磁
気モーメント、１５：ガラス基板、１６：ＮｉＯ、１
７：ＣｏＴａＺｒ、１８：磁気ディスク、１９：磁気ヘ
ッド部、２０：スライダー、２１：磁気ヘッド用アー
ム、２２：駆動系、２３：半導体レーザーヘッド、２
４：半導体レーザーヘッド用アーム、２５：レーザー光
線、２６：基板、２７：媒体部、２８：半導体レーザ
ー、２９：ミラー、３０：レンズ、３１：ハウジング、
３２：アーム、３３：レーザー光線、３４：ポールピー
ス、３５：コイル、３６：磁場検出部、３７：磁気シー
ルド、３８：磁気ヘッド保持部、３９：光ファイバー、
４０：高抵抗体薄膜、４１：強磁性体、４２：反強磁性
体、４３：界面、４４：強磁性体、４５：反強磁性体、
４６：基板、４７：非磁性体、４８：フェリ磁性体、５
０：磁気ディスク、８００：非磁性体膜。1,100,900: ferromagnetic film, 2,200: antiferromagnetic film, 3,300: substrate, 4: protective film, 5: magnetization,
6: magnetic moment, 7: interface, 8: laser beam,
9: magnetic head, 10: magnetization curve, 11: magnetization curve, 1
2: ferrimagnetic film, 13: magnetic moment, 14: magnetic moment, 15: glass substrate, 16: NiO, 1
7: CoTaZr, 18: magnetic disk, 19: magnetic head, 20: slider, 21: arm for magnetic head, 22: drive system, 23: semiconductor laser head, 2
4: arm for semiconductor laser head, 25: laser beam, 26: substrate, 27: medium, 28: semiconductor laser, 29: mirror, 30: lens, 31: housing,
32: arm, 33: laser beam, 34: pole piece, 35: coil, 36: magnetic field detector, 37: magnetic shield, 38: magnetic head holder, 39: optical fiber,
40: high-resistance thin film, 41: ferromagnetic, 42: antiferromagnetic, 43: interface, 44: ferromagnetic, 45: antiferromagnetic,
46: substrate, 47: non-magnetic material, 48: ferrimagnetic material, 5
0: magnetic disk, 800: non-magnetic film.
Claims (11)
気ディスクにおいて、磁性層として強磁性体と反強磁性
体をそれぞれ１層以上使用した多層膜、あるいは強磁性
体とフェリ磁性体をそれぞれ１層以上使用した多層膜と
することを特徴とする磁気ディスク。1. A magnetic disk comprising a substrate, an underlayer, a magnetic layer, and a protective film, a multilayer film using at least one ferromagnetic material and an antiferromagnetic material as a magnetic layer, or a ferromagnetic material and a ferrimagnetic material. A multi-layer film using at least one layer of each of the following.
あるいはフェリ磁性体の平均結晶粒径を１０nm以下とす
る請求項１記載の磁気ディスク。2. The magnetic disk according to claim 1, wherein the average crystal grain size of the antiferromagnetic material or ferrimagnetic material having a magnetic transition temperature of room temperature or higher is 10 nm or less.
求項１または２記載の磁気ディスク。3. The magnetic disk according to claim 1, wherein the ferromagnetic materials are arranged on the substrate in an array.
気ディスクと、その駆動手段と、磁性層に情報を記録す
る記録用磁気ヘッドと、再生時 磁性層 からの漏れ磁場
を検出する再生用磁気ヘッドと、記録・再生用磁気ヘッ
ドを保持する手段と、ヘッドを保持する手段を駆動する
手段から構成される磁気記録装置において、前記磁気デ
ィスクは基板、下地層、磁性層、保護膜からなる磁気デ
ィスクにおいて、磁性層として強磁性体と反強磁性体を
それぞれ１層以上使用した多層膜、あるいは強磁性体と
フェリ磁性体をそれぞれ１層以上使用した多層膜である
ことを特徴とする磁気記録装置。4. A magnetic disk having a magnetic layer for magnetically recording information, driving means for the magnetic disk, a recording magnetic head for recording information on the magnetic layer, and detecting a leakage magnetic field from the magnetic layer during reproduction. In a magnetic recording apparatus including a reproducing magnetic head, a unit for holding a recording / reproducing magnetic head, and a unit for driving a unit for holding the head, the magnetic disk includes a substrate, an underlayer, a magnetic layer, and a protective film. A magnetic layer comprising a ferromagnetic material and at least one ferromagnetic material as a magnetic layer, or a multi-layer film using at least one ferromagnetic material and a ferrimagnetic material as a magnetic layer. Magnetic recording device.
度を持つ反強磁性体あるいはフェリ磁性体の平均結晶粒
径を１０nm以下とした請求項４記載の磁気記録装置。5. The magnetic recording apparatus according to claim 4, wherein the magnetic disk has an average crystal grain size of an antiferromagnetic material or a ferrimagnetic material having a magnetic transition temperature equal to or higher than room temperature of 10 nm or less.
基板上に配置した請求項４または５記載の磁気記録装
置。6. The magnetic recording apparatus according to claim 4, wherein the ferromagnetic materials of the magnetic disk are arranged on a substrate in an array.
た請求項４ないし6のいずれかに記載の磁気記録装置。7. The magnetic recording apparatus according to claim 4, further comprising means for locally heating the magnetic layer.
Tc以下のネール温度TNを持つ反強磁性体を使用し、記録
時、ビット近傍をTN付近、あるいはそれ以上に加熱する
請求項７記載の磁気記録装置。8. A ferromagnetic material having a Curie temperature Tc as a magnetic layer.
8. The magnetic recording apparatus according to claim 7, wherein an antiferromagnetic material having a Neel temperature TN equal to or lower than Tc is used, and during recording, the bit vicinity is heated to near TN or higher.
とTc1以下のキュリー温度Tc2を持つフェリ磁性体を使用
し、記録時、磁性層をTc2近傍に加熱し、再生時、記録
層を加熱しない、あるいはフェリ磁性体の補償温度以上
Tc2以下に加熱する請求項７記載の磁気記録装置。9. Using the ferrimagnetic material having ferromagnetic and T c1 below the Curie temperature T c2 of the Curie temperature T c1 as a magnetic layer, and heating time of recording, a magnetic layer in the vicinity of T c2, during reproduction, Do not heat the recording layer or exceed the compensation temperature of the ferrimagnetic material
The magnetic recording apparatus according to claim 7, wherein the magnetic recording apparatus is heated to Tc2 or less.
導体レーザーを備えた請求項７記載の磁気記録装置。10. The magnetic recording apparatus according to claim 7, wherein a semiconductor laser is provided as means for locally heating the magnetic layer.
抵抗体の通電加熱手段を備えた請求項７記載の磁気記録
装置。11. The magnetic recording apparatus according to claim 7, further comprising a high-resistance current-carrying means as a means for locally heating the magnetic layer.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP9934397A JPH10289434A (en) | 1997-04-16 | 1997-04-16 | Magnetic disk and magnetic recordor using the magnetic disk |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP9934397A JPH10289434A (en) | 1997-04-16 | 1997-04-16 | Magnetic disk and magnetic recordor using the magnetic disk |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH10289434A true JPH10289434A (en) | 1998-10-27 |
Family
ID=14244979
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP9934397A Pending JPH10289434A (en) | 1997-04-16 | 1997-04-16 | Magnetic disk and magnetic recordor using the magnetic disk |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH10289434A (en) |
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