JPS63237242A - Magneto-optical recording system - Google Patents
Magneto-optical recording systemInfo
- Publication number
- JPS63237242A JPS63237242A JP62070278A JP7027887A JPS63237242A JP S63237242 A JPS63237242 A JP S63237242A JP 62070278 A JP62070278 A JP 62070278A JP 7027887 A JP7027887 A JP 7027887A JP S63237242 A JPS63237242 A JP S63237242A
- Authority
- JP
- Japan
- Prior art keywords
- magnetic layer
- temperature
- recording
- coercive force
- magnetic
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 239000000758 substrate Substances 0.000 claims abstract description 9
- 230000005415 magnetization Effects 0.000 claims description 32
- 238000000034 method Methods 0.000 claims description 15
- 230000001678 irradiating effect Effects 0.000 claims description 2
- 230000002441 reversible effect Effects 0.000 abstract description 3
- 230000005381 magnetic domain Effects 0.000 abstract 1
- 239000010410 layer Substances 0.000 description 63
- 238000004544 sputter deposition Methods 0.000 description 12
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 8
- 229910052786 argon Inorganic materials 0.000 description 4
- 230000000694 effects Effects 0.000 description 4
- 230000003993 interaction Effects 0.000 description 4
- 229910052761 rare earth metal Inorganic materials 0.000 description 4
- 238000010586 diagram Methods 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- 150000002910 rare earth metals Chemical class 0.000 description 3
- 229910005091 Si3N Inorganic materials 0.000 description 2
- 238000002474 experimental method Methods 0.000 description 2
- 229920000515 polycarbonate Polymers 0.000 description 2
- 239000004417 polycarbonate Substances 0.000 description 2
- 239000011241 protective layer Substances 0.000 description 2
- 229910052723 transition metal Inorganic materials 0.000 description 2
- 229910001020 Au alloy Inorganic materials 0.000 description 1
- 235000017166 Bambusa arundinacea Nutrition 0.000 description 1
- 235000017491 Bambusa tulda Nutrition 0.000 description 1
- 241001330002 Bambuseae Species 0.000 description 1
- 229910017061 Fe Co Inorganic materials 0.000 description 1
- 229910000640 Fe alloy Inorganic materials 0.000 description 1
- 239000004831 Hot glue Substances 0.000 description 1
- 230000005374 Kerr effect Effects 0.000 description 1
- 235000015334 Phyllostachys viridis Nutrition 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 239000011425 bamboo Substances 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 230000005684 electric field Effects 0.000 description 1
- 239000003353 gold alloy Substances 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 230000002427 irreversible effect Effects 0.000 description 1
- 229910001004 magnetic alloy Inorganic materials 0.000 description 1
- 239000013028 medium composition Substances 0.000 description 1
- 230000035945 sensitivity Effects 0.000 description 1
- 230000001568 sexual effect Effects 0.000 description 1
- 230000007704 transition Effects 0.000 description 1
- 150000003624 transition metals Chemical class 0.000 description 1
Landscapes
- Recording Or Reproducing By Magnetic Means (AREA)
Abstract
Description
【発明の詳細な説明】
（産業上の利用分野〕
本発明は、磁気カー効果を利用して読み出しすることの
できるキュリー点及び補償点記録タイプの光磁気記録媒
体を使用した、重ね古き可能な光磁気記録方式に関する
。DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention provides a multi-layer recording medium using a Curie point and compensation point recording type magneto-optical recording medium that can be read using the magnetic Kerr effect. Concerning magneto-optical recording methods.
（従来の技術）
消去可能な尤メモリとして光磁気メモリが知られている
。光磁気メモリは、従来の磁気ヘッドを使った磁気記録
媒体と比べて高密度記録、非接触での記録再生などが可
能であるという長所がある反面、記録面に一度記録部分
を消去しなければならない（一方向に着磁しなければな
らない）という欠点があった。この欠点を補う為に、記
録再生用ヘッドと消去用ヘッドを別々に設ける方式、あ
るいは、レーザーの連続ビームを照射すると同時に磁場
を変調しながら印加して記録する方式などが提案されて
いる。(Prior Art) Magneto-optical memory is known as an erasable memory. Magneto-optical memory has the advantage of being capable of high-density recording and non-contact recording and playback compared to magnetic recording media using conventional magnetic heads. It had the disadvantage that it cannot be magnetized in one direction (it must be magnetized in one direction). In order to compensate for this drawback, proposals have been made such as a method in which a recording/reproducing head and an erasing head are provided separately, or a method in which recording is performed by applying a modulated magnetic field at the same time as a continuous laser beam is irradiated.
しかし、これらの方法は、装置が大がかりとなり、コス
ト高になる欠点あるいは高速の変調が出来ないなどの欠
点を有する。However, these methods have disadvantages such as a large-scale apparatus, high cost, or inability to perform high-speed modulation.
本発明は上述従来例の欠点を除去し、従来の光磁気メモ
リの装置構成に簡易な構造の磁界発生手段を付設するだ
けで、磁気記録媒体と同様な重ね書き（オーバーライド
）を可能とした、光磁気記録方式を提供することを目的
とする。The present invention eliminates the drawbacks of the above-mentioned conventional example, and makes it possible to perform overwriting similar to that of a magnetic recording medium by simply adding a magnetic field generating means of a simple structure to the device configuration of a conventional magneto-optical memory. The purpose is to provide a magneto-optical recording system.
（問題点を解決するための手段）
Ｆ記目的達成可能な本発明は、
低いキュリー温度（”ｒｔ、 ’）と高い保磁力（Ｈｕ
）を有する第１磁性層と、この磁性層に比べて相対的に
高いキュリー温度（ＴＨ）と低い保磁力（ＨＬ）を＜ｒ
Ｌ且つ室温とキュリー温度（Ｔｏ）の間に補償温度（
ＴＣＯＭＰ）を有する第２磁性層とからなる、交換結合
をした二層構造の垂直磁化膜をＪ！：板ヒに有して成る
光磁気記録媒体を使用して、第１磁性層から記録情報を
読み出すようにした、次の二値の記録を行なうこを特徴
とする記録方式である。(Means for Solving the Problems) The present invention, which can achieve the objective F, has a low Curie temperature ("rt, ') and a high coercive force (Hu
) and a relatively high Curie temperature (TH) and low coercivity (HL) compared to this magnetic layer < r
L and the compensation temperature (To) between room temperature and Curie temperature (To)
J! J! : This is a recording method characterized by performing the following binary recording, in which recorded information is read from the first magnetic layer using a magneto-optical recording medium provided on a plate.
（ａ）該媒体に対して記録用ヘッドと異なる場所で、保
磁力ＨＢの第２磁性層を一方向に磁化するのに充分で保
磁力Ｈ１１の第１磁性層の磁化の向きを反転させること
のない大きさの外部磁界ＨＥを加え、
（ｂ）次に記録用ヘッドにより、バイアス磁界Ｈ８を印
加すると同時に低いキュリー温度（ＴＬ）付近まで且つ
補償温度（Ｔｃｏｖｐ）付近まで該媒体が昇温するだけ
のレーザーパワーを照射するとにより、第１磁性層の磁
化の向きを第２磁性層に対して安定な向きにそろえる第
１種の記録と、補償温度（ＴＣＯＭＰ）以トに該媒体が
昇温するだけのレーザーパワーを照射することにより第
２磁性層の磁化の向きを反転させ、「１η記第１種の記
録と反対方向に第１磁性層の磁化の向きをそろえる第２
種の記録と、の二値の記録
［実施態様と作用］
本発明に用いる光磁気メモリ用媒体の基本的構成は、透
光性基板りに第１＠性層と第２磁性層を順次６１層した
ものである。第１＠性層は低りキュリー温度（ＴＬ）と
高い保磁力（ＨＨ）を有し、第２磁性層は、高いキュリ
ー温度（ＴＨ）と低い保磁力（ｔ’ｔｔ、 ）を有しか
つ室温とキュリー温度との間に補償温度（ＴＣＱＭＰ）
をイｒする。ここで「高いＪ、「低い」とは両磁性層を
比較した場合の相対的な関係を表わす（保磁力は室温に
おける比較）。ただし、通常は第１＠性層のＴＬは７０
〜１８０℃、）Ｉｎは、３〜２０にＯｅ 、第２磁性層
のＴ１１は１５０〜４００℃、Ｈｌ、は１〜３にＯｃ、
ＴｃｏＭＰはＴ５．程度の範囲内にするとよい。 丼磁
性層の材料には、ｉ］ｊ直磁電磁気異方性し［つ比較的
大きな磁気光学効果を■するものが利用できるが、第１
磁性層にはＴｂ−Ｆｃ 、 Ｔｂ−Ｄｙ−Ｆｅ、Ｄｙ−
Ｆｅ、Ｔｂ−Ｐｅ−Ｇｏ、Ｔｂ−Ｄｙ−１’ｅ−Ｇｏ
、 Ｄｙ−Ｆｅ−（：ｏ等、第２磁性層には。(a) Reversing the direction of magnetization of the first magnetic layer with coercive force H11 at a location different from the recording head on the medium, sufficient to magnetize the second magnetic layer with coercive force HB in one direction; (b) Next, a bias magnetic field H8 is applied by the recording head, and at the same time the temperature of the medium is raised to around the low Curie temperature (TL) and around the compensation temperature (Tcovp). Type 1 recording, in which the direction of magnetization of the first magnetic layer is aligned in a stable direction with respect to the second magnetic layer, and the temperature of the medium is raised above the compensation temperature (TCOMP) by irradiating laser power of The direction of magnetization of the second magnetic layer is reversed by irradiation with a laser power equal to
Recording of seeds and recording of binary values [Embodiment and operation] The basic structure of the magneto-optical memory medium used in the present invention is that the first @ magnetic layer and the second magnetic layer are sequentially formed on a transparent substrate at 61° C. It is layered. The first magnetic layer has a low Curie temperature (TL) and a high coercive force (HH), and the second magnetic layer has a high Curie temperature (TH) and a low coercive force (t'tt, ). Compensation temperature (TCQMP) between room temperature and Curie temperature
Input. Here, "high J" and "low" refer to the relative relationship when comparing both magnetic layers (coercive force is compared at room temperature). However, normally the TL of the first @sexual layer is 70
~180°C, ) In is Oe from 3 to 20, T11 of the second magnetic layer is 150 to 400°C, Hl is Oc from 1 to 3,
TcoMP is T5. It is best to keep it within a certain range. As the material for the bowl magnetic layer, materials that have i]j direct magnetoelectromagnetic anisotropy [and have a relatively large magneto-optical effect can be used, but the first
The magnetic layer contains Tb-Fc, Tb-Dy-Fe, Dy-
Fe, Tb-Pe-Go, Tb-Dy-1'e-Go
, Dy-Fe-(:o, etc., in the second magnetic layer.
Ｔｂ−Ｆｅ 、 Ｔｂ−Ｄｙ−Ｆｅ、 Ｄｙ−ｒｅ ％
Ｔｂ−Ｆｅ−Ｃｏ、 Ｔｂ−Ｄｙ−Ｆｅ−（：ｏ、
Ｄｙ−Ｆｅ−Ｇｏ 、 Ｇｄ−Ｔｂ−Ｆｅ、 Ｇｄ−
Ｔｂ−Ｄｙ−Ｆｅ、Ｇｄ−Ｄｙ−Ｆｅ、 Ｇｄ−Ｔｂ−
Ｆｅ−Ｇｏ 、Ｇｄ−Ｔｂ−Ｄｙ−Ｆｅ−Ｇｏ、Ｇｄ−
ＤｙＦｅ−Ｇｏ等の希土類元素と遷移金属元素との非晶
質磁性合金が好ましい。Tb-Fe, Tb-Dy-Fe, Dy-re%
Tb-Fe-Co, Tb-Dy-Fe-(:o,
Dy-Fe-Go, Gd-Tb-Fe, Gd-
Tb-Dy-Fe, Gd-Dy-Fe, Gd-Tb-
Fe-Go, Gd-Tb-Dy-Fe-Go, Gd-
An amorphous magnetic alloy of a rare earth element and a transition metal element such as DyFe-Go is preferred.
なお、透光性の基板と磁性層の間や、磁性層の、該基板
と反対側に、耐久性を向トさせるための、あるいは記録
消去感度と磁気光学効果を向トさせるための適当な誘電
体層、あるいは反射層を設けてもよい。It should be noted that a suitable material may be added between the transparent substrate and the magnetic layer, or on the side of the magnetic layer opposite to the substrate, in order to improve durability, or to improve recording/erasing sensitivity and magneto-optic effect. A dielectric layer or a reflective layer may also be provided.
上述したような光磁気メモリ用媒体を用いることにより
実施できる本発明を以下、図面を参１１ｑシて詳細に説
明する。The present invention, which can be implemented using the magneto-optical memory medium as described above, will be described in detail below with reference to the drawings.
図１は本発明における記録過程を説明する図である。１
が第１磁性層、２が第２磁性層を示１−０（ａ）〜（ｇ
）の丼々は、両磁性層の磁化の状態を示す。記録過程中
、記録用ヘッドと異なる場所で、保磁力ＨＬの第２磁性
層を一方向に磁化するのに充分で保磁力Ｈ１，の第１磁
性層の磁化の向きを反転させることのない大きさの外部
磁界ＨＢが下方に印加されていて、さらに、記録用ヘッ
ドの場所において第２＠性層への記録を助けるバイアス
磁界Ｈｎが下方に印加されている。FIG. 1 is a diagram explaining the recording process in the present invention. 1
1-0(a) to (g) indicates the first magnetic layer and 2 indicates the second magnetic layer.
) indicates the state of magnetization of both magnetic layers. During the recording process, at a location different from the recording head, the magnitude is sufficient to magnetize the second magnetic layer with a coercive force HL in one direction and does not reverse the direction of magnetization of the first magnetic layer with a coercive force H1. An external magnetic field HB is applied downwardly, and a bias magnetic field Hn is further applied downwardly at the location of the recording head to assist in recording in the second @-type layer.
記録過程をその過程に従って説明する何に、その理解の
助けとなるように、まず、（ａ）〜 （ｇ）により表わ
される状態の概要及び各状態間の移行過程の様子等につ
いて説明しておく。To help you understand the recording process, I will first explain the outline of the states represented by (a) to (g) and the transition process between each state. .
（ａ）と（ｇ）は室温における２値の記録状態を示して
いて、レーザー光により加熱によって、（ｂ）（ｃ）
（ｄ）と温度が上昇する。（ｂ）と （「）、（Ｃ）と
（ｅ）はほぼ同じ温度での別の状態を示しいる。図中、
←は温度に対して可逆的な磁化過程を示し、→や←は非
可逆的な磁化過程を示す。また、（ｂ）ト（ｃ）、ある
いは（ｅ）と （ｆ）の間には、第２！ｆｉ性層の補償
温度が存在する。図１の例では、第１＆ｆｉ性層が希土
類格子磁化優勢であって、第２磁性層も希り類格子磁化
優勢の場合を示している。この場合には、両層間の交換
相互作用によって両層の磁化か平行な（ｇ）が安定状態
であり、反平行である（ａ）が不安定状態であって、こ
の不安定状態（ａ）では界面磁壁か存在する。ただし、
電界零でも不安定状態を保持することが可能であるよう
に、第２＠性層の保磁力を調整する必要がある。室温状
態Ｈａ） 、 （ｇ） ）では保磁力の小さい第２磁
性層の磁化は外部磁界Ｈ６によって常に図で下向きとな
っている。(a) and (g) show the binary recording state at room temperature, and by heating with laser light, (b) and (c)
(d) and the temperature increases. (b) and (''), (C) and (e) show different states at approximately the same temperature.In the figure,
← indicates a magnetization process that is reversible with respect to temperature, and → and ← indicate an irreversible magnetization process. Also, between (b) and (c), or between (e) and (f), there is a second! There is a compensation temperature of the fi-sensitive layer. The example in FIG. 1 shows a case where the first &fi layer has dominant rare earth lattice magnetization, and the second magnetic layer also has dominant rare earth lattice magnetization. In this case, due to the exchange interaction between the two layers, the parallel magnetization (g) is a stable state, and the antiparallel magnetization (a) is an unstable state, and this unstable state (a) Then, an interfacial domain wall exists. however,
It is necessary to adjust the coercive force of the second @-type layer so that an unstable state can be maintained even when the electric field is zero. At room temperature (Ha), (g)), the magnetization of the second magnetic layer, which has a small coercive force, is always directed downward in the figure due to the external magnetic field H6.
次に記録過程をその過程に従って説明する（ａ）の状態
から温度を上げると、図３に示すように第１磁性層の保
磁力が低下し、第２磁性層の保磁力が大きくなる。する
と、交換相互作用により両層の磁化が平行になろうとす
るために、第１磁性層の磁化が反転し下を向く（ｂ）。Next, the recording process will be explained according to the process.When the temperature is increased from the state shown in (a), the coercive force of the first magnetic layer decreases and the coercive force of the second magnetic layer increases, as shown in FIG. Then, because the magnetizations of both layers tend to become parallel due to exchange interaction, the magnetization of the first magnetic layer is reversed and points downward (b).
この状態から温度を下げると、磁化状態が変化しないま
ま冷え、（ｇ）の状態に移る。（ｇ）の状態から温度を
トげ、（ｂ）の状態になった後、温度を下げてもやはり
（ｇ）の状態に移る。即ち、（ｂ）の温度に相当するレ
ーザーパワーの印加によって、（ａ）の状態も（ｇ）の
状態もすべて（ｇ）の状態に移る。When the temperature is lowered from this state, the magnetization state remains unchanged and the state changes to state (g). After the temperature is increased from state (g) to state (b), the state still changes to state (g) even if the temperature is lowered. That is, by applying a laser power corresponding to the temperature (b), both the state (a) and the state (g) are transferred to the state (g).
次に、（ｂ）の状態からさらに温度をトげ、第２磁性層
の補償温度ＴＣＯＭ＋−を越して（Ｃ）の状態になると
、第２磁性層の磁化が可逆的に反転する。さらに温度を
Ｌげると第２磁、竹屑の保磁力が小さくなり、バイアス
磁界Ｈ８により反転する（ｄ）。この状態から温度を下
げると磁化状態が変化しないまま冷えＴＣＯＭＰを越す
と第２磁性層の磁化が可逆的に反転する。その前後で、
交換相互作用により第１磁性層の磁化が−Ｆ向きに生じ
、そのまま室温にまで冷え、第２磁性層が再び小さな保
磁力となり、外部磁界ＨＥにより反転する。ただし、こ
の際には第１磁性層の保磁力は大きいので、外部磁界Ｈ
Ｅによっては反転せず、記録状態を保持している。即ち
、（ｄ）の温度に相当するレーザーパワーの印加によっ
て（ａ）の状態も（ｇ）の状態もすべて（ａ）の状態に
移る。Next, when the temperature is further increased from the state (b), exceeding the compensation temperature TCOM+- of the second magnetic layer and reaching the state (C), the magnetization of the second magnetic layer is reversibly reversed. When the temperature is further increased by L, the coercive force of the second magnet and bamboo chips becomes smaller and is reversed by the bias magnetic field H8 (d). When the temperature is lowered from this state, the magnetization state remains unchanged, and when TCOMP is exceeded, the magnetization of the second magnetic layer is reversibly reversed. Before and after that,
Due to the exchange interaction, the magnetization of the first magnetic layer is generated in the −F direction, which is then cooled down to room temperature, and the second magnetic layer again has a small coercive force and is reversed by the external magnetic field HE. However, in this case, since the coercive force of the first magnetic layer is large, the external magnetic field H
Depending on E, the recording state is maintained without being reversed. That is, by applying laser power corresponding to the temperature (d), both the state (a) and the state (g) are transferred to the state (a).
従って、異なるレーザーパワーの印加によって異なる磁
化状態を取ることができ、即ちこれはＩｌｌね古き（オ
ーバーライド）が実現したことになる。Therefore, different magnetization states can be obtained by applying different laser powers, that is, override has been achieved.
図２の例では第１磁性層が遷移金属副格子磁化優勢で、
第２磁性層が希土類副格子磁化優勢の場合を示している
。この場合には、両層間の交換相互作用によって、両層
の磁化が反平行な（ａ）が安定状態であり、平行である
（ｇ）が不安定状態であって、この不安定状態（ｇ）で
は界面壁が存在する。図１の場合と同様、（ｂ）の温度
に相当するレーザーパワーの印加によって、（ａ）の状
態も（ｇ）の状態もすべて（ａ）の状態に移り、（ｄ）
の温度に相当するレーザーパワーの印加によって、（ａ
）の状態も（ｇ）の状態もすべて（ｇ）の状態に移る。In the example of FIG. 2, the first magnetic layer has dominant transition metal sublattice magnetization,
A case is shown in which the second magnetic layer has dominant rare earth sublattice magnetization. In this case, due to the exchange interaction between the two layers, (a) where the magnetizations of both layers are antiparallel is a stable state, and (g) where they are parallel is an unstable state, and this unstable state (g ), there is an interfacial wall. As in the case of Fig. 1, by applying laser power corresponding to the temperature of (b), both the state of (a) and the state of (g) shift to the state of (a), and the state of (d)
By applying a laser power corresponding to the temperature of (a
) and state (g) all shift to state (g).
従って、やはり異なるレーザーパワーの印加によって異
なる磁化状態を取ることができる。即ち、これは重ね書
き（オーバーライド）が実現したことになる。Therefore, different magnetization states can be obtained by applying different laser powers. In other words, this means that overwriting has been achieved.
なお、ＨＢの大きさはＨｌ：の大きさよりも小さい。Ｈ
Ｂの方がＨＥよりも大きければＨ６は必要ないが、媒体
の組成や膜厚の制御がむずかしくなかなり大きくなり、
そのような磁界の下で、図１の（ｆ）や図２の（ｂ）の
状態を磁界に逆って交換力によって実現するのはかなり
難しい。また、第２磁性層が補償温度を有することによ
って、図１の（ｆ）や図２の（ｆ）の状態の第２ｆｆｌ
性層の磁化の向きが、ＨＨに対して安定である効果があ
る。Note that the size of HB is smaller than the size of Hl:. H
If B is larger than HE, H6 is not necessary, but it is difficult to control the medium composition and film thickness, and it becomes quite large.
Under such a magnetic field, it is quite difficult to realize the states of FIG. 1(f) and FIG. 2(b) by exchange force against the magnetic field. Furthermore, since the second magnetic layer has a compensation temperature, the second ffl in the state shown in FIG. 1(f) or FIG. 2(f) is
This has the effect that the direction of magnetization of the magnetic layer is stable against HH.
（実施例）
実施例１
３元のターゲット源を備えたスパッタ装置内に、プリグ
ループ、プリフォーマット１３号の刻まれたポリカーボ
ネート製のディスク状基板を、ターゲットとの間の距１
１０ｃｍの間隔にセットし、回転させた。(Example) Example 1 A polycarbonate disc-shaped substrate with pregroup and preformat No. 13 engraved thereon was placed in a sputtering apparatus equipped with three target sources at a distance of 1 from the target.
They were set at 10 cm intervals and rotated.
アルゴン中で、第１のターゲットより、スパッタ速度
１００人／ｍｉｎ、スパッタ圧５Ｘ １０’ Ｔｏｒｒ
でＳｉ３Ｎ、を保護層として７００人の厚さに設けた。Sputtering speed from the first target in argon
100 people/min, sputtering pressure 5X 10' Torr
A protective layer of Si3N was applied to a thickness of 700 mm.
次にアルゴン中で、第２のターゲットよりスパッタ速度
１００人／ｍｉｎ、スパッタ圧５×ｌＯ°３Ｔｏｒｒで
ＴｂＦｅ合金をスパッタし、膜厚５００人、ＴＬ＝約１
３０℃、Ｈ７１＝約５ ＫＯｅのＴｂ副格−ｆ磁化優勢
の第１１１Ｉｉ性層を形成した。Next, in argon, TbFe alloy was sputtered from a second target at a sputtering rate of 100 mm/min and a sputtering pressure of 5×10°3 Torr, with a film thickness of 500 mm and TL=approximately 1.
A 111Ii layer with dominant Tb sub-f magnetization was formed at 30° C. and H71=approximately 5 KOe.
次に、アルゴン中で、第３のターゲットよりスパッタ速
度１００人／ｍｉｎ、スパッタ圧５ｘ ＩＱ−’ Ｔｏ
ｒｒでＧｄ−Ｔｂ−Ｆｅ−Ｇｏ金合金スパッタし、膜厚
８００人。Next, in argon, sputtering was performed from a third target at a sputtering rate of 100 people/min and a sputtering pressure of 5x IQ-' To
Gd-Tb-Fe-Go gold alloy sputtered with RR, film thickness 800mm.
Ｔ、、＝約２２０℃、ＨＢ、＝約１．５にＯｅ 、ＴＣ
ＯＭＰ＝約１４０℃のＧｄＴｂ副格子磁化優勢の第２磁
性層を形成した。T, = about 220℃, HB, = about 1.5 Oe, TC
A second magnetic layer with dominant GdTb sublattice magnetization was formed at an OMP of about 140°C.
次にアルゴン中で第１のターゲットよりスパッタ速度
！００人／ｍｉｎ、スパッタ圧５Ｘ １Ｏ−３Ｔｏｒｒ
で、Ｓｉ３Ｎ、を保護層として７００人の厚さに設けた
。Next, the sputtering speed is increased from the first target in argon.
! 00 people/min, sputtering pressure 5X 1O-3Torr
A protective layer of Si3N was formed to a thickness of 700 mm.
次に、上記の膜形成を終えた基板を、ホットメルト接着
剤を用いて、ポリカーボネートの貼り合わせ用基板と貼
り合わせ光磁気ディスクを作製した。この光磁気ディス
クを記録再生装置にセットし、２０００ｅのバイアス磁
界と２にＯｅの外部磁界を印加しつつ、線速度約８ｍ／
ｓｅｃ、約１．５μｍに集光した８３０ｎｍの波長のレ
ーザービームを５０％のデユーティで２ＭＩ＋７．で変
調させながら、２．７ｍＷと５゜５ｍ１ｆの２値のレー
ザーパワーで記録を行なった。Next, the substrate on which the film had been formed was bonded to a polycarbonate bonding substrate using a hot melt adhesive to produce a magneto-optical disk. This magneto-optical disk was set in a recording/reproducing device, and while applying a bias magnetic field of 2000e and an external magnetic field of 2 Oe, a linear velocity of about 8m/
sec, a laser beam with a wavelength of 830 nm focused to about 1.5 μm was applied at a duty of 50% for 2MI+7. Recording was performed using a binary laser power of 2.7 mW and 5°5 m1f while modulating the laser power.
その後１ｍＷのレーザービームを照射して再生を行なっ
たところ、２値の１８号の再生ができた。Thereafter, a 1 mW laser beam was irradiated to perform reproduction, and binary No. 18 was successfully reproduced.
次に、上記お実験を行なった後、同一トラックヒに３Ｍ
１ｌｚ、同一、パワーで記録を行なった。この結果、餌
に記録された１３号は検出されず、オーバーライドがｎ
１能であることが確認された。Next, after performing the above experiment, 3M
Recordings were made at 1lz, the same power. As a result, No. 13 recorded in the bait was not detected and the override was n.
It was confirmed that he was fully functional.
実施例２
第１磁性層として、第２のターゲットよりスパッタ速度
１００人／ｍｉｎ、スパッタ圧５ｘ １Ｏ−３Ｔｏｒｒ
でＴｂ−Ｆｅ合金をスパッタし、ｎｑ膜厚５００人ＴＬ
＝約１２５℃、Ｈｌ、＝約４にＯＣのＦｅ副格子磁化優
勢の磁性層を形成した以外は実施例１と同様な光磁気デ
ィスクを作製し、同様の実験を行な、つた。Example 2 The first magnetic layer was sputtered from a second target at a sputtering rate of 100 people/min and a sputtering pressure of 5x 1O-3 Torr.
sputtered Tb-Fe alloy with nq film thickness of 500 TL
A magneto-optical disk was prepared in the same manner as in Example 1 except that a magnetic layer in which the Fe sublattice magnetization of OC was dominant was formed at a temperature of about 125° C., a Hl of about 4, and a similar experiment was carried out.
その結果、やはりオーバーライドが可能であることが確
認された。As a result, it was confirmed that override is still possible.
以ト詳細に説明したように、光磁気メモリ用媒体として
、低いキュリー温度（ＴＬ）と高い保磁力（ＨＨ）を有
する第１磁性層と、この磁性層に比べて相対的に高いキ
ュリー温度（Ｔ１１）と低い保磁力（ＨＬ）を存し且つ
室温とキュリー温度（Ｔ、、）の間に補償温度を有する
第２磁性層とからなる。交換結合をした二層構造の電電
磁化膜を基板トに有して成る媒体を用い、記録時に、記
録用ヘッドと異なる場所に磁界発生部を設け、２値のレ
ーザーパワーで記録することにより、重ね計さくオーバ
ーライド）が可能になった。As explained in detail above, as a magneto-optical memory medium, a first magnetic layer having a low Curie temperature (TL) and a high coercive force (HH), and a first magnetic layer having a relatively high Curie temperature (HH) compared to this magnetic layer are used. T11) and a second magnetic layer having a low coercive force (HL) and a compensation temperature between room temperature and the Curie temperature (T, , ). By using a medium having a two-layer exchange-coupled electromagnetic film on the substrate, and during recording, a magnetic field generating section is provided at a location different from the recording head, and recording is performed using binary laser power. Override) is now possible.
【図面の簡単な説明】
図１９図２は本発明の記録過程を説明するための図、図
３は第１磁性層と第２磁性層の保磁力と温度との関係を
示す概略図である。
１．３＝第１磁性層
２．４：第２磁性層[Brief Description of the Drawings] Fig. 19 Fig. 2 is a diagram for explaining the recording process of the present invention, and Fig. 3 is a schematic diagram showing the relationship between coercive force and temperature of the first magnetic layer and the second magnetic layer. . 1.3=first magnetic layer 2.4: second magnetic layer
Claims (1)
）を有する第１磁性層と、この磁性層に比べて相対的に
高いキュリー温度（Ｔ＿Ｈ）と低い保磁力（Ｈ＿Ｌ）を
有し且つ室温とキュリー温度（Ｔ＿Ｈ）の間に補償温度
（Ｔ＿Ｃ＿Ｏ＿Ｍ＿Ｐ）を有する第２磁性層とからなる
、交換結合をした二層構造の垂直磁化膜を基板上に有し
て成る光磁気記録媒体を使用して、第１磁性層から記録
情報を読み出すようにした、次の二値の記録を行なうこ
を特徴とする記録方式。 （ａ）該媒体に対して記録用ヘッドと異なる場所で、保
磁力Ｈ＿Ｌの第２磁性層を一方向に磁化するのに充分で
保磁力Ｈ＿Ｈの第１磁性層の磁化の向きを反転させるこ
とのない大きさの外部磁界Ｈ＿εを加え、 （ｂ）次に記録用ヘッドにより、バイアス磁界Ｈ＿Ｂを
印加すると同時に低いキュリー温度（Ｔ＿Ｌ）付近まで
且つ補償温度（Ｔ＿Ｃ＿Ｏ＿Ｍ＿Ｐ）付近まで、該媒体
が昇温するだけのレーザーパワーを照射するとにより、
第１磁性層の磁化の向きを第２磁性層に対して安定な向
きにそろえる第１種の記録と、補償温度（Ｔ＿Ｃ＿Ｏ＿
Ｍ＿Ｐ）以上に該媒体が昇温するだけのレーザーパワー
を照射することにより第２磁性層の磁化の向きを反転さ
せ、前記第１種の記録と反対方向に第１磁性層の磁化の
向きをそろえる第２種の記録と、の二値の記録[Claims] 1) Low Curie temperature (T_L) and high coercive force (H_H)
), and a first magnetic layer having a relatively high Curie temperature (T_H) and low coercive force (H_L) compared to this magnetic layer, and a compensation temperature (T_C_O_M_P) between room temperature and the Curie temperature (T_H). Recorded information is read out from the first magnetic layer using a magneto-optical recording medium having a perpendicularly magnetized film with an exchange-coupled two-layer structure on a substrate. , a recording method characterized by recording the following binary values. (a) Reversing the direction of magnetization of the first magnetic layer with coercive force H_H at a location different from the recording head with respect to the medium, sufficient to magnetize the second magnetic layer with coercive force H_L in one direction; (b) Next, the recording head applies a bias magnetic field H_B and at the same time raises the temperature of the medium to around the low Curie temperature (T_L) and around the compensation temperature (T_C_O_M_P). By applying enough laser power to
The first type of recording, which aligns the magnetization direction of the first magnetic layer in a stable direction with respect to the second magnetic layer, and the compensation temperature (T_C_O_
M_P) The direction of magnetization of the second magnetic layer is reversed by irradiating the medium with a laser power sufficient to raise the temperature above that level, and the direction of magnetization of the first magnetic layer is reversed to the direction of the first type of recording. The second type of record that is aligned, and the binary record of
Priority Applications (15)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62070278A JPS63237242A (en) | 1987-03-26 | 1987-03-26 | Magneto-optical recording system |
| CA 541367 CA1340058C (en) | 1986-07-08 | 1987-07-06 | Magnetooptical recording medium allowing overwriting with tow or more magnetic layers and recording method utilizing the same |
| AU75306/87A AU593364C (en) | 1986-07-08 | 1987-07-07 | Magnetooptical recording medium allowing overwriting with two or more magnetic layers and recording method utilizing the same |
| AT98200007T ATE216528T1 (en) | 1986-07-08 | 1987-07-08 | APPARATUS AND SYSTEM FOR RECORDING ON A MAGNETOPTICAL RECORDING MEDIUM |
| EP98200007A EP0838815B1 (en) | 1986-07-08 | 1987-07-08 | Apparatus and system for recording on a magnetooptical recording medium |
| DE3752222T DE3752222T2 (en) | 1986-07-08 | 1987-07-08 | Magnetic optical recording medium with the possibility of overwriting with two or more magnetic layers and recording method using this medium |
| KR1019870007322A KR960003420B1 (en) | 1986-07-08 | 1987-07-08 | Magneto optical recording medium |
| EP98200006A EP0838814B1 (en) | 1986-07-08 | 1987-07-08 | Magnetooptical recording medium allowing overwriting with two or more magnetic layers and recording method utilizing the same |
| EP87306038A EP0258978B1 (en) | 1986-07-08 | 1987-07-08 | Magnetooptical recording medium allowing overwriting with two or more magnetic layers and recording method utilizing the same |
| AT87306038T ATE172047T1 (en) | 1986-07-08 | 1987-07-08 | MAGNETOPTICAL RECORDING MEDIUM WITH THE POSSIBILITY OF OVERWRITING WITH TWO OR MORE MAGNETIC LAYERS AND RECORDING METHOD USING SUCH MEDIUM |
| US07/475,941 US5132945A (en) | 1986-07-08 | 1990-01-30 | Magnetooptical recording medium allowing overwriting with two or more magnetic layers and recording method utilizing the same |
| US08/296,163 US5525378A (en) | 1986-07-08 | 1994-08-26 | Method for producing a magnetooptical recording medium |
| US08/312,930 US5481410A (en) | 1986-07-08 | 1994-09-30 | Magnetooptical recording medium allowing overwriting with two or more magnetic layers and recording method utilizing the same |
| US08/613,431 US5783300A (en) | 1986-06-18 | 1996-02-29 | Magnetooptical recording medium allowing overwriting with two or more magnetic layers and recording method utilizing the same |
| US09/080,215 US6028824A (en) | 1986-07-08 | 1998-05-18 | Magnetooptical recording medium allowing overwriting with two or more magnetic layers |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62070278A JPS63237242A (en) | 1987-03-26 | 1987-03-26 | Magneto-optical recording system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS63237242A true JPS63237242A (en) | 1988-10-03 |
Family
ID=13426874
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP62070278A Pending JPS63237242A (en) | 1986-06-18 | 1987-03-26 | Magneto-optical recording system |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS63237242A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6464152A (en) * | 1987-05-20 | 1989-03-10 | Nippon Telegraph & Telephone | Magneto-optical recording system |
| US5599619A (en) * | 1991-10-18 | 1997-02-04 | International Business Machines Corporation | Write once magneto-optic media and system |
-
1987
- 1987-03-26 JP JP62070278A patent/JPS63237242A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6464152A (en) * | 1987-05-20 | 1989-03-10 | Nippon Telegraph & Telephone | Magneto-optical recording system |
| US5599619A (en) * | 1991-10-18 | 1997-02-04 | International Business Machines Corporation | Write once magneto-optic media and system |
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