JPH0434744A - Production of magneto-optical or magnetic disk - Google Patents
Production of magneto-optical or magnetic diskInfo
- Publication number
- JPH0434744A JPH0434744A JP14056090A JP14056090A JPH0434744A JP H0434744 A JPH0434744 A JP H0434744A JP 14056090 A JP14056090 A JP 14056090A JP 14056090 A JP14056090 A JP 14056090A JP H0434744 A JPH0434744 A JP H0434744A
- Authority
- JP
- Japan
- Prior art keywords
- recording layer
- magnetic field
- external magnetic
- magneto
- optical
- 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
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 13
- 230000005415 magnetization Effects 0.000 claims abstract description 14
- 230000001678 irradiating effect Effects 0.000 abstract description 7
- 238000000034 method Methods 0.000 description 10
- 239000004065 semiconductor Substances 0.000 description 9
- 230000000694 effects Effects 0.000 description 3
- 229910001218 Gallium arsenide Inorganic materials 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 239000000758 substrate Substances 0.000 description 2
- 229910000980 Aluminium gallium arsenide Inorganic materials 0.000 description 1
- 230000005374 Kerr effect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000005530 etching Methods 0.000 description 1
- 150000004820 halides Chemical class 0.000 description 1
- 238000001459 lithography Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 238000000059 patterning Methods 0.000 description 1
- 238000003825 pressing Methods 0.000 description 1
- 238000004549 pulsed laser deposition Methods 0.000 description 1
Classifications
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
- G11B5/74—Record carriers characterised by the form, e.g. sheet shaped to wrap around a drum
- G11B5/743—Patterned record carriers, wherein the magnetic recording layer is patterned into magnetic isolated data islands, e.g. discrete tracks
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
- G11B5/74—Record carriers characterised by the form, e.g. sheet shaped to wrap around a drum
- G11B5/82—Disk carriers
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
- G11B2005/0002—Special dispositions or recording techniques
- G11B2005/0005—Arrangements, methods or circuits
- G11B2005/0021—Thermally assisted recording using an auxiliary energy source for heating the recording layer locally to assist the magnetization reversal
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
- G11B5/012—Recording on, or reproducing or erasing from, magnetic disks
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は、光磁気または磁気ディスクの製造方法に関し
、特に、再生専用の光磁気または磁気ディスクの製造に
適用して好適なものである。DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for manufacturing a magneto-optical or magnetic disk, and is particularly suitable for manufacturing a magneto-optical or magnetic disk for read-only use.
本発明は、光磁気または磁気ディスクの製造方法におい
て、記録層に垂直方向に第１の外部磁場を印加すること
により記録層の磁化の方向を第１の外部磁場の方向にそ
ろえた後、記録層に第１の外部磁場と逆方向の第２の外
部磁場を印加した状態で記録すべき信号に対応した開口
が形成されたマスクを用いて記録層にレーザ光を選択的
に照射してこの照射部の記録層の磁化を反転させること
により信号を記録するようにすることによって、再生専
用の光磁気または磁気ディスクを大量複製することがで
きるようにしたものである。In a method for manufacturing a magneto-optical or magnetic disk, the present invention applies a first external magnetic field perpendicularly to the recording layer to align the direction of magnetization of the recording layer with the direction of the first external magnetic field, and then performs recording. This is done by selectively irradiating the recording layer with laser light using a mask in which an opening corresponding to the signal to be recorded is formed while a second external magnetic field in the opposite direction to the first external magnetic field is applied to the layer. By recording signals by reversing the magnetization of the recording layer of the irradiation section, it is possible to make mass copies of read-only magneto-optical or magnetic disks.
光記録用のディスクとしては、オーディオ用としてはＣ
Ｄ（コンパクトディスク）、ビデオ用としてはＬＤ（レ
ーザーディスク）が普及しているが、これらのＣＤやＬ
Ｄはいずれも再生専用である。そして、これらのＣＤや
ＬＤは、記録すべき信号に対応したビットが形成された
スタンパをプラスチックディスクに押しつけて大容量の
信号ピットを一度に形成することにより容易に製造され
ることから、大量複製が可能となっている。For optical recording discs, for audio use, C.
D (compact disc) and LD (laser disc) are popular for video, but these CDs and L
Both D are for reproduction only. These CDs and LDs are easily manufactured by pressing a stamper on which bits corresponding to the signal to be recorded are formed onto a plastic disk to form a large capacity of signal pits at once, making them easy to reproduce in large quantities. is possible.
上述のようにＣＤ−ＰＬＤは大量複製が可能であるのに
対して、光磁気ディスクや磁気ディスクは、信号をカー
効果を利用して磁気光学的に読み出したり、磁気ヘッド
を用いて読み出したりするものであるため、再生専用の
光磁気ディスクや磁気ディスクを大量複製する方法は未
だ開発されていなかった。As mentioned above, CD-PLDs are capable of mass duplication, whereas magneto-optical disks and magnetic disks read out signals magneto-optically using the Kerr effect or using magnetic heads. As such, a method for mass duplicating read-only magneto-optical disks and magnetic disks had not yet been developed.
従って本発明の目的は、再生専用の光磁気または磁気デ
ィスクを大量複製することができる光磁気または磁気デ
ィスクの製造方法を提供することにある。SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a method for manufacturing a magneto-optical or magnetic disk, which enables mass duplication of read-only magneto-optical or magnetic disks.
上記目的を達成するために、本発明は、光磁気または磁
気ディスクの製造方法において、記録層（２）に垂直方
向に第１の外部磁場（Ｈｌ）を印加することにより記録
層（２）の磁化の方向を第１の外部磁場（Ｈｌ）の方向
にそろえた後、記録層（２）に第１の外部磁場（Ｈｌ）
と逆方向の第２の外部磁場（Ｈｗ）を印加した状態で記
録すべき信号に対応した開口（３ａ）が形成されたマス
ク（３）を用いて記録層（２）にレーザ光（５）を選択
的に照射してこの照射部の記録層（２）の磁化を反転さ
せることにより信号を記録するようにしている。In order to achieve the above object, the present invention provides a method for manufacturing a magneto-optical or magnetic disk by applying a first external magnetic field (Hl) perpendicularly to the recording layer (2). After aligning the direction of magnetization with the direction of the first external magnetic field (Hl), the first external magnetic field (Hl) is applied to the recording layer (2).
A laser beam (5) is applied to the recording layer (2) using a mask (3) in which an aperture (3a) corresponding to the signal to be recorded is formed while a second external magnetic field (Hw) in the opposite direction is applied. is selectively irradiated to reverse the magnetization of the recording layer (2) in the irradiated area, thereby recording a signal.
上述のように構成された本発明の光磁気または磁気ディ
スクの製造方法によれば、記録層（２）に垂直方向に第
１の外部磁場（Ｈ，）を印加してこの記録層（２）の磁
化の方向を第１の外部磁場（Ｈｌ）の方向にそろえるこ
とにより、初期化が行われる０次に、記録層（２）に第
１の外部磁場（Ｈｌ）と逆方向の第２の外部磁場（Ｈ，
）を印加した状態で記録すべき信号に対応した開口（３
ａ）が形成されたマスク（３）を用いて記録層（２）に
レーザ光（５）を選択的に照射することにより、この照
射部の記録層（２）が選択的に加熱される。そして、こ
のようにして選択的に加熱された部分の記録層（２）の
磁化は、第１の外部磁場（Ｈ＋ ）と逆方向に印加され
た第２の外部磁場（Ｈｗ）により反転し、これによって
信号が記録される。According to the method for manufacturing a magneto-optical or magnetic disk of the present invention configured as described above, the first external magnetic field (H, ) is applied perpendicularly to the recording layer (2) to Initialization is performed by aligning the magnetization direction of the first external magnetic field (Hl) with the direction of the first external magnetic field (Hl). External magnetic field (H,
) is applied and the aperture (3
By selectively irradiating the recording layer (2) with laser light (5) using the mask (3) on which a) is formed, the recording layer (2) in this irradiated area is selectively heated. Then, the magnetization of the recording layer (2) in the portion selectively heated in this way is reversed by a second external magnetic field (Hw) applied in the opposite direction to the first external magnetic field (H+), This records the signal.
このようにして、信号が記録された光磁気または磁気デ
ィスクが容易に製造されることから、再生専用の光磁気
または磁気ディスクを大量複製することができる。In this way, magneto-optical or magnetic disks on which signals are recorded can be easily manufactured, making it possible to mass-produce read-only magneto-optical or magnetic disks.
以下、本発明の一実施例について図面を参照しながら説
明する。An embodiment of the present invention will be described below with reference to the drawings.
第１図Ａ−Ｄは本発明の一実施例による光磁気または磁
気ディスクの製造方法を工程順に示す断面図であり、第
２図Ａ−Ｄはそれぞれ第１図Ａ〜Ｄに対応する平面図で
ある。1A to 1D are cross-sectional views showing a method for manufacturing a magneto-optical or magnetic disk according to an embodiment of the present invention in order of steps, and FIGS. 2A to 2D are plan views corresponding to FIGS. 1A to D, respectively. It is.
第１図Ａ及び第２図Ａに示すように、まず基板■上に垂
直磁化膜から成る記録層２が形成された光磁気または磁
気ディスクに垂直方向に初期化用の外部磁場Ｈ＋を印加
する。この場合、記録層２の保磁力をＨ９とすると、Ｈ
＋＞Ｈｅである。ただし、この初期化時に後述のように
レーザ光５を照射することにより熱アシストを行う場合
には、Ｈｒ ＜ Ｈｃでもよい、なお、記録層２中の矢
印は磁化を示す（以下同様）。As shown in FIG. 1A and FIG. 2A, first, an external magnetic field H+ for initialization is applied in the perpendicular direction to a magneto-optical or magnetic disk on which a recording layer 2 made of a perpendicularly magnetized film is formed on a substrate. . In this case, if the coercive force of the recording layer 2 is H9, then H
+>He. However, if thermal assist is performed by irradiating the laser beam 5 during this initialization as described later, Hr < Hc may be satisfied. Note that the arrow in the recording layer 2 indicates magnetization (the same applies hereinafter).
次に、第１図Ｂ及び第２図Ｂに示すように、記録すべき
信号に対応した多数の開口３ａが形成されたマスク３（
第３図参照）を記録層２上に載せる。ここで、このマス
ク３は、後述のレーザ光５が透過しない材料により形成
され、例えばこのレーザ光５が透過しない材料の膜をリ
ソグラフィー及びエツチング技術を用いてバターニング
することにより形成される。Next, as shown in FIGS. 1B and 2B, a mask 3 (
(see FIG. 3) is placed on the recording layer 2. Here, the mask 3 is formed of a material that does not transmit the laser beam 5, which will be described later, and is formed, for example, by patterning a film of the material that does not transmit the laser beam 5 using lithography and etching techniques.
次に、第１図Ｃ及び第２図Ｃに示すように、例えば半導
体レーザチップ（図示せず）を複数個ライン状に並べた
半導体レーザアレイ４によりディスク径よりも幅の大き
いライン状のレーザ光５を形成し、記録層２上にマスク
３が載せられた上述の光磁気または磁気ディスクをこの
半導体レーザアレイ４の下側を例えばレーザ光５の長手
方向に垂直方向に移動させることにより、マスク３の全
面にレーザ光５を照射する。ここで、このレーザ光５の
照射は、外部磁場Ｈ１と逆方向の外部磁場Ｈｗを記録層
２に印加した状態で行う、この場合には、レーザ光５の
照射により熱アシストが行われることから、Ｈｔｍ（Ｈ
ｃでよい。このようにしてマスク３の全面にレーザ光５
を照射することにより、このマスク３の開口３ａを通過
したレーザ光５により照射された部分の記録層２が選択
的に加熱されてこの部分の温度が上昇する。そして、外
部磁場Ｈ＋ と逆方向に印加された外部磁場Ｈｗにより
、この温度が上昇した部分の記録層２の磁化が反転し、
これによって信号が記録される（第４図参照）。Next, as shown in FIG. 1 C and FIG. By forming the light 5 and moving the above-mentioned magneto-optical or magnetic disk with the mask 3 placed on the recording layer 2 under the semiconductor laser array 4 in a direction perpendicular to the longitudinal direction of the laser light 5, The entire surface of the mask 3 is irradiated with laser light 5. Here, the irradiation with the laser beam 5 is performed while an external magnetic field Hw in the opposite direction to the external magnetic field H1 is applied to the recording layer 2. In this case, thermal assist is performed by the irradiation with the laser beam 5. , Htm(H
c is fine. In this way, the laser beam 5 is applied to the entire surface of the mask 3.
By irradiating the recording layer 2, the portion of the recording layer 2 irradiated by the laser beam 5 passing through the opening 3a of the mask 3 is selectively heated, and the temperature of this portion increases. Then, due to the external magnetic field Hw applied in the opposite direction to the external magnetic field H+, the magnetization of the recording layer 2 in the portion where the temperature has increased is reversed.
This records the signal (see Figure 4).
このようにして、第１図り及び第２図りに示すように、
信号が記録された光磁気または磁気ディスクが製造され
る。In this way, as shown in the first and second diagrams,
A magneto-optical or magnetic disk with recorded signals is manufactured.
なお、レーザ光５を発生させるための半導体レーザとし
ては、例えばＧａＡｓ／ＡｌＧａＡｓ半導体レーザが用
いられ、この場合のレーザ光５０波長は７８０〜８３０
ｎｍである。また、このレーザ光５のパワーは、この
レーザ光５の照射部の記録層２の温度が高くなり過ぎな
いように選ばれる。これは、特に記録層２が多結晶膜ま
たはアモルファス膜の場合に、記録ビットとしての磁区
間の界面が乱れたり、結晶化が生じたりするのを防止す
るためである。Note that as a semiconductor laser for generating the laser beam 5, for example, a GaAs/AlGaAs semiconductor laser is used, and the wavelength of the laser beam 50 in this case is 780 to 830.
It is nm. Further, the power of this laser beam 5 is selected so that the temperature of the recording layer 2 at the irradiated portion of this laser beam 5 does not become too high. This is to prevent the interface between the magnetic segments serving as recording bits from being disturbed or from crystallizing, especially when the recording layer 2 is a polycrystalline film or an amorphous film.
以上のように、この実施例によれば、あらかじめ初期化
された記録層２に外部磁場Ｈ＠を印加した状態で、記録
すべき信号に対応した開口３ａが形成されたマスク３を
用いてこの記録層２にレーザ光５を選択的に照射するこ
とにより信号を記録しているので、信号が記録された光
磁気または磁気ディスクを容易に製造することができる
。これによって、再生専用の光磁気または磁気ディスク
を容易に大量複製することができる。このような再生専
用の光磁気または磁気ディスクは、例えばオーディオ用
またはビデオ用のソフトディスクとして用いることがで
きる。As described above, according to this embodiment, while an external magnetic field H@ is applied to the recording layer 2 that has been initialized in advance, the mask 3 in which the aperture 3a corresponding to the signal to be recorded is formed is used to record the signal. Since signals are recorded by selectively irradiating the recording layer 2 with laser light 5, a magneto-optical or magnetic disk on which signals are recorded can be easily manufactured. This allows easy mass duplication of read-only magneto-optical or magnetic disks. Such a reproduction-only magneto-optical or magnetic disk can be used, for example, as an audio or video soft disk.
以上、本発明の実施例につき具体的に説明したが、本発
明は、上述の実施例に限定されるものではなく、本発明
の技術的思想に基づく各種の変形が可能である。Although the embodiments of the present invention have been specifically described above, the present invention is not limited to the above-described embodiments, and various modifications can be made based on the technical idea of the present invention.
例えば、上述の実施例においては、半導体レーザアレイ
４を用いてライン状のレーザ光５を形成しているが、こ
のライン状のレーザ光５は必ずしも半導体レーザアレイ
４を用いて形成する必要はなく、他の方法により形成す
ることも可能である。For example, in the above embodiment, the semiconductor laser array 4 is used to form the line-shaped laser beam 5, but the line-shaped laser beam 5 does not necessarily have to be formed using the semiconductor laser array 4. , it is also possible to form by other methods.
また、このレーザ光５としては、ＧａＡｓ／ＡｌＧａＡ
ｓ半導体レーザ以外の半導体レーザで発生されたものを
用いることも可能であり、さらには半導体レーザ以外の
レーザにより発生させたものを用いることも可能である
０例えば、このレーザ光５として、ＸｅＣ１エキシマ−
レーザー（波長３０８ｎｍ）、ＫｒＦエキシマ−レーザ
ー（波長２４８１ｍ） 、 ＸｅＦエキシマ−レーザー
（波長３０８ ｎｍ）などの希ガスハライドエキシマ−
レーザーにより発生されたものを用いることも可能であ
る。高密度記録を行うために記録ビットの大きさを小さ
くする場合にはマスク３の開口３ａの大きさも小さくす
る必要があることから、上述の希ガスハライドエキシマ
−レーザーなどにより発生される短波長のレーザ光をレ
ーザ光５として用いることは、マスク３の開口３ａをレ
ーザ光５が通過するときの回折効果を少なくする上で有
効である。Moreover, as this laser beam 5, GaAs/AlGaA
It is also possible to use light generated by a semiconductor laser other than the s semiconductor laser, and furthermore, it is also possible to use light generated by a laser other than the semiconductor laser. For example, as this laser light 5, XeC1 excimer −
Rare gas halide excimer such as laser (wavelength 308 nm), KrF excimer laser (wavelength 2481 m), XeF excimer laser (wavelength 308 nm)
It is also possible to use those generated by a laser. When reducing the size of recording bits for high-density recording, it is necessary to reduce the size of the aperture 3a of the mask 3. Using a laser beam as the laser beam 5 is effective in reducing the diffraction effect when the laser beam 5 passes through the aperture 3a of the mask 3.
以上述べたように、本発明によれば、記録層に第１の外
部磁場と逆方向の第２の外部磁場を印加した状態で記録
すべき信号に対応した開口が形成されたマスクを用いて
記録層にレーザ光を選択的に照射してこの照射部の記録
層の磁化を反転させることにより信号を記録するように
しているので、信号が記録された光磁気または磁気ディ
スクを容易に製造することができ、これによって再生専
用の光磁気または磁気ディスクを大量複製することがで
きる。As described above, according to the present invention, a mask in which an opening corresponding to a signal to be recorded is formed while a second external magnetic field in the opposite direction to the first external magnetic field is applied to the recording layer is used. Since signals are recorded by selectively irradiating the recording layer with laser light and reversing the magnetization of the recording layer in the irradiated area, it is easy to manufacture magneto-optical or magnetic disks on which signals are recorded. This enables mass duplication of read-only magneto-optical or magnetic disks.
第１図Ａ−Ｄは本発明の一実施例による光磁気または磁
気ディスクの製造方法を工程順に示す断面図、第２図Ａ
−Ｄはそれぞれ第１図Ａ−Ｄに対応する平面図、第３図
は本発明の一実施例による光磁気または磁気ディスクの
製造方法において用いられるマスクの一部分の拡大平面
図、第４図はレーザ光照射時の記録層及びマスクの一部
分の拡大断面図である。
図面における主要な符号の説明
１：基板、 ２：記録層、 ３：マスク、３ａ：開口、
４：半導体レーザアレイ、５：レーザ光。1A to 1D are cross-sectional views showing the manufacturing method of a magneto-optical or magnetic disk according to an embodiment of the present invention in the order of steps, and FIG. 2A
-D are plan views corresponding to FIGS. 1A-D, respectively, FIG. 3 is an enlarged plan view of a portion of a mask used in a method for manufacturing a magneto-optical or magnetic disk according to an embodiment of the present invention, and FIG. 4 is a plan view corresponding to FIGS. FIG. 3 is an enlarged cross-sectional view of a portion of the recording layer and mask during laser beam irradiation. Explanation of main symbols in the drawings 1: Substrate, 2: Recording layer, 3: Mask, 3a: Opening,
4: Semiconductor laser array, 5: Laser light.
Claims (1)
り上記記録層の磁化の方向を上記第１の外部磁場の方向
にそろえた後、上記記録層に上記第１の外部磁場と逆方
向の第２の外部磁場を印加した状態で記録すべき信号に
対応した開口が形成されたマスクを用いて上記記録層に
レーザ光を選択的に照射してこの照射部の上記記録層の
磁化を反転させることにより信号を記録するようにした
光磁気または磁気ディスクの製造方法。After aligning the direction of magnetization of the recording layer with the direction of the first external magnetic field by applying a first external magnetic field perpendicularly to the recording layer, applying a first external magnetic field to the recording layer in a direction opposite to the first external magnetic field. While applying a second external magnetic field, the recording layer is selectively irradiated with laser light using a mask in which an aperture corresponding to the signal to be recorded is formed, and the magnetization of the recording layer in the irradiated area is changed. A method of manufacturing a magneto-optical or magnetic disk in which signals are recorded by reversing the disk.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP14056090A JPH0434744A (en) | 1990-05-30 | 1990-05-30 | Production of magneto-optical or magnetic disk |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP14056090A JPH0434744A (en) | 1990-05-30 | 1990-05-30 | Production of magneto-optical or magnetic disk |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH0434744A true JPH0434744A (en) | 1992-02-05 |
Family
ID=15271522
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP14056090A Pending JPH0434744A (en) | 1990-05-30 | 1990-05-30 | Production of magneto-optical or magnetic disk |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0434744A (en) |
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0545690A2 (en) * | 1991-12-02 | 1993-06-09 | Nikon Corporation | Reproduction-only magnetooptical disk, and reproduction method and reproduction apparatus therefor |
| EP0596136A1 (en) * | 1992-05-19 | 1994-05-11 | Nikon Corporation | Read-only optomagnetic disk, and reproducing method and equipment |
| EP1122718A2 (en) * | 2000-02-03 | 2001-08-08 | Mitsubishi Chemical Corporation | Method for forming a magnetic pattern in a magnetic recording medium, method for producing a magnetic recording medium, magnetic pattern forming device, magnetic recording medium and magnetic recording device |
| JP2003514324A (en) * | 1999-11-12 | 2003-04-15 | シーゲイト テクノロジー エルエルシー | Patterning of magnetic media using thermally induced phase transition |
| US6731446B2 (en) | 2000-02-03 | 2004-05-04 | Matsushita Electric Industrial Co., Ltd. | Method for forming a magnetic pattern in a magnetic recording medium, method for producing a magnetic recording medium, magnetic pattern forming device, magnetic recording medium and magnetic recording device |
| US6781779B2 (en) | 2000-05-16 | 2004-08-24 | Matsushita Electric Industrial Co., Ltd. | Magnetic recording medium, its production method and magnetic recording apparatus |
| US6816330B2 (en) | 2000-12-22 | 2004-11-09 | Matsushita Electric Industrial Co., Ltd. | Method for forming a magnetic pattern in a magnetic recording medium, magnetic recording medium magnetic recording device and photomask |
| US6950261B2 (en) | 2001-01-24 | 2005-09-27 | Matsushita Electric Industrial Co., Ltd. | Magnetic pattern forming method, magnetic pattern forming apparatus, magnetic disk, and magnetic recording apparatus |
| KR100809760B1 (en) * | 2001-08-07 | 2008-03-04 | 마쯔시다덴기산교 가부시키가이샤 | Method and apparatus for forming magnetization pattern of magnetic recording medium, magnetic recording medium and method for manufacturing the same, and magnetic recording apparatus |
-
1990
- 1990-05-30 JP JP14056090A patent/JPH0434744A/en active Pending
Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0545690A2 (en) * | 1991-12-02 | 1993-06-09 | Nikon Corporation | Reproduction-only magnetooptical disk, and reproduction method and reproduction apparatus therefor |
| EP0596136A1 (en) * | 1992-05-19 | 1994-05-11 | Nikon Corporation | Read-only optomagnetic disk, and reproducing method and equipment |
| EP0596136A4 (en) * | 1992-05-19 | 1995-03-29 | Nippon Kogaku Kk | Read-only optomagnetic disk, and reproducing method and equipment. |
| JP2003514324A (en) * | 1999-11-12 | 2003-04-15 | シーゲイト テクノロジー エルエルシー | Patterning of magnetic media using thermally induced phase transition |
| EP1122718A2 (en) * | 2000-02-03 | 2001-08-08 | Mitsubishi Chemical Corporation | Method for forming a magnetic pattern in a magnetic recording medium, method for producing a magnetic recording medium, magnetic pattern forming device, magnetic recording medium and magnetic recording device |
| EP1122718A3 (en) * | 2000-02-03 | 2003-10-15 | Mitsubishi Chemical Corporation | Method for forming a magnetic pattern in a magnetic recording medium, method for producing a magnetic recording medium, magnetic pattern forming device, magnetic recording medium and magnetic recording device |
| US6731446B2 (en) | 2000-02-03 | 2004-05-04 | Matsushita Electric Industrial Co., Ltd. | Method for forming a magnetic pattern in a magnetic recording medium, method for producing a magnetic recording medium, magnetic pattern forming device, magnetic recording medium and magnetic recording device |
| US6781779B2 (en) | 2000-05-16 | 2004-08-24 | Matsushita Electric Industrial Co., Ltd. | Magnetic recording medium, its production method and magnetic recording apparatus |
| US6816330B2 (en) | 2000-12-22 | 2004-11-09 | Matsushita Electric Industrial Co., Ltd. | Method for forming a magnetic pattern in a magnetic recording medium, magnetic recording medium magnetic recording device and photomask |
| KR100846003B1 (en) * | 2000-12-22 | 2008-07-11 | 마쯔시다덴기산교 가부시키가이샤 | Method for forming a magnetic pattern in a magnetic recording medium, magnetic recording medium, magnetic recording device and photomask |
| US6950261B2 (en) | 2001-01-24 | 2005-09-27 | Matsushita Electric Industrial Co., Ltd. | Magnetic pattern forming method, magnetic pattern forming apparatus, magnetic disk, and magnetic recording apparatus |
| KR100809760B1 (en) * | 2001-08-07 | 2008-03-04 | 마쯔시다덴기산교 가부시키가이샤 | Method and apparatus for forming magnetization pattern of magnetic recording medium, magnetic recording medium and method for manufacturing the same, and magnetic recording apparatus |
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