JPH0673199B2 - Magneto-optical recording medium - Google Patents
Magneto-optical recording mediumInfo
- Publication number
- JPH0673199B2 JPH0673199B2 JP30079986A JP30079986A JPH0673199B2 JP H0673199 B2 JPH0673199 B2 JP H0673199B2 JP 30079986 A JP30079986 A JP 30079986A JP 30079986 A JP30079986 A JP 30079986A JP H0673199 B2 JPH0673199 B2 JP H0673199B2
- Authority
- JP
- Japan
- Prior art keywords
- film
- magnetic
- layer
- magneto
- recording medium
- 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.)
- Expired - Lifetime
Links
- 239000010408 film Substances 0.000 claims description 39
- 239000010410 layer Substances 0.000 claims description 32
- 230000005415 magnetization Effects 0.000 claims description 20
- 239000000758 substrate Substances 0.000 claims description 7
- 239000011241 protective layer Substances 0.000 claims description 6
- 230000035699 permeability Effects 0.000 claims description 4
- 239000010409 thin film Substances 0.000 claims description 2
- 229910001004 magnetic alloy Inorganic materials 0.000 claims 1
- 229910045601 alloy Inorganic materials 0.000 description 8
- 239000000956 alloy Substances 0.000 description 8
- 239000007789 gas Substances 0.000 description 8
- 229910000684 Cobalt-chrome Inorganic materials 0.000 description 6
- 239000010952 cobalt-chrome Substances 0.000 description 6
- 239000000203 mixture Substances 0.000 description 5
- 238000004544 sputter deposition Methods 0.000 description 5
- 238000010586 diagram Methods 0.000 description 4
- 230000015654 memory Effects 0.000 description 4
- 230000001678 irradiating effect Effects 0.000 description 3
- 229910000599 Cr alloy Inorganic materials 0.000 description 2
- 230000008901 benefit Effects 0.000 description 2
- 230000008034 disappearance Effects 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 230000006870 function Effects 0.000 description 2
- 239000011521 glass Substances 0.000 description 2
- 230000005381 magnetic domain Effects 0.000 description 2
- 230000003287 optical effect Effects 0.000 description 2
- 229910000640 Fe alloy Inorganic materials 0.000 description 1
- 229910002546 FeCo Inorganic materials 0.000 description 1
- 229910052688 Gadolinium Inorganic materials 0.000 description 1
- 229910052689 Holmium Inorganic materials 0.000 description 1
- 229910001030 Iron–nickel alloy Inorganic materials 0.000 description 1
- 229910004298 SiO 2 Inorganic materials 0.000 description 1
- 229910052771 Terbium Inorganic materials 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 230000002996 emotional effect Effects 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 239000000696 magnetic material Substances 0.000 description 1
- 238000001755 magnetron sputter deposition Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 229910052759 nickel Inorganic materials 0.000 description 1
- AJCDFVKYMIUXCR-UHFFFAOYSA-N oxobarium;oxo(oxoferriooxy)iron Chemical compound [Ba]=O.O=[Fe]O[Fe]=O.O=[Fe]O[Fe]=O.O=[Fe]O[Fe]=O.O=[Fe]O[Fe]=O.O=[Fe]O[Fe]=O.O=[Fe]O[Fe]=O AJCDFVKYMIUXCR-UHFFFAOYSA-N 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 229910000889 permalloy Inorganic materials 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 229910052761 rare earth metal Inorganic materials 0.000 description 1
- 150000002910 rare earth metals Chemical class 0.000 description 1
- 238000005546 reactive sputtering Methods 0.000 description 1
- 230000035945 sensitivity Effects 0.000 description 1
- 229910052723 transition metal Inorganic materials 0.000 description 1
- 150000003624 transition metals Chemical class 0.000 description 1
Description
【発明の詳細な説明】 （産業上の利用分野） 本発明は光磁気メモリに用いられる記録媒体に関するも
のであり、更に詳しくは、膜面と垂直方向に磁化容易軸
を有する磁性膜を記録層とし、レーザなどの光ビームを
照射した領域に反転磁区を作ることにより情報を記録す
ることができ、磁気光学効果を利用して読み出すことの
できる光磁気記録媒体に関するものである。Description: TECHNICAL FIELD The present invention relates to a recording medium used in a magneto-optical memory, and more specifically, a magnetic layer having a magnetic easy axis in a direction perpendicular to the film surface of the recording layer. Further, the present invention relates to a magneto-optical recording medium capable of recording information by forming a reversed magnetic domain in a region irradiated with a light beam such as a laser and capable of reading by utilizing a magneto-optical effect.
（従来の技術） 光メモリは大容量ファイルメモリの一つとして注目され
ている。中でも光磁気メモリは、記録情報の書き替えが
可能であるという利点を持っていることから、各所で盛
んに研究されている。その記録媒体としては、Tb,Gd,D
y,Hoなどの希土類金属とFe,Co,Niなどの遷移金属との組
み合わせによって作製される非晶質磁性薄膜が、記録感
度が高い、粒界ノイズがない膜面に垂直方向の磁気異方
性を有する膜が容易に作れるなどの利点を有するため、
最も有望視されている。(Prior Art) An optical memory attracts attention as one of large-capacity file memories. Among them, the magneto-optical memory has the advantage that the recorded information can be rewritten, and is therefore actively studied in various places. The recording medium is Tb, Gd, D
Amorphous magnetic thin films prepared by combining rare earth metals such as y and Ho and transition metals such as Fe, Co and Ni are magnetically anisotropic in the perpendicular direction to the film surface with high recording sensitivity and no grain boundary noise. Since it has the advantage that a film with properties can be easily made,
Most promising.
従来、この様な記録媒体に対する情報の記録・消失は次
の様に行われる。記録は、一方向に着磁した記録媒体に
レーザ光ビームを照射して、媒体温度をキューリ温度Tc
もしくは補償温度Tcomp以上に上昇させ、外部印加磁界
と記録媒体の反磁界によって反転磁区を形成することに
より行われる。消失は、外部磁界を記録時とは逆極性に
印加し、レーザ光ビームを記録時と同等の強度で記録媒
体に一様に照射する。いわゆる一括消失により行われ
る。これにより記録媒体の磁化状態は、記録前の初期状
態に戻る。Conventionally, recording / erasing of information on such a recording medium is performed as follows. Recording is performed by irradiating a recording medium magnetized in one direction with a laser light beam to change the medium temperature to the Curie temperature Tc.
Alternatively, it is performed by increasing the temperature above the compensation temperature Tcomp and forming an inverted magnetic domain by an externally applied magnetic field and a demagnetizing field of the recording medium. For the disappearance, an external magnetic field is applied in the opposite polarity to that at the time of recording, and the laser light beam is uniformly applied to the recording medium at the same intensity as that at the time of recording. This is done by so-called collective disappearance. As a result, the magnetization state of the recording medium returns to the initial state before recording.
（発明が解決しようとする問題点） この様に、従来の光磁気記録媒体に対して、記録を行う
場合には、レーザ光ビームを発生する光学系以外に、外
部磁界印加手段が必須であるため、光磁気記録・再生装
置の構成は、複雑になる傾向があった。(Problems to be Solved by the Invention) As described above, when recording is performed on the conventional magneto-optical recording medium, the external magnetic field applying means is indispensable in addition to the optical system for generating the laser light beam. Therefore, the structure of the magneto-optical recording / reproducing apparatus tends to be complicated.
本発明の目的は、外部磁界印加手段を必要とせずにバイ
アス磁界を印加することができる光磁気記録媒体を提供
することにある。An object of the present invention is to provide a magneto-optical recording medium capable of applying a bias magnetic field without the need for an external magnetic field applying means.
（問題点を解決するための手段） 本発明の光磁気記録媒体は、基体上に、高透磁率磁性体
層が形成され、この上、膜面に垂直方向に、磁気異方性
を有する第１の垂直磁化膜から成る感情凸部が一定間隔
で形成され、次に第２の垂直磁化膜から成る記録層、誘
電体から成る保護層の順に形成され、更に前記第１及び
第２の垂直磁化膜が同一方向に着磁させることを特徴と
する。(Means for Solving the Problems) In the magneto-optical recording medium of the present invention, a high-permeability magnetic layer is formed on a substrate, and a magnetic layer having magnetic anisotropy is formed in the direction perpendicular to the film surface. The emotional protrusions composed of one perpendicular magnetic film are formed at regular intervals, then the recording layer composed of the second perpendicular magnetic film and the protective layer composed of a dielectric are formed in this order, and the first and second perpendicular magnetic films are formed. The magnetizing film is magnetized in the same direction.
（作用） 基体上に、高透磁率磁性体層と絶縁体層を介して形成さ
れた垂直磁化膜からなる凸部と、第２の垂直磁化膜から
成る記録層を、同じ垂直方向に着磁しておくことによっ
て、記録層は一方向に初期着磁されると共に、前記凸部
の間にある記録層部分には、突起部の磁化によって、初
期着磁とは逆向きにバイアス磁界が印加される。上記高
透磁率磁化体層は、記録層部分に、上記バイアス磁界を
効率良く導く働きをする。(Function) A convex portion formed of a perpendicular magnetic film formed through a high magnetic permeability magnetic layer and an insulating layer on a substrate and a recording layer formed of a second perpendicular magnetic film are magnetized in the same perpendicular direction. By doing so, the recording layer is initially magnetized in one direction, and a bias magnetic field is applied to the recording layer portion between the protrusions in the direction opposite to the initial magnetization due to the magnetization of the protrusions. To be done. The high-permeability magnet layer serves to efficiently guide the bias magnetic field to the recording layer portion.
（実施例） 次に本発明の実施例について図面を用いて詳細に説明す
る。第１図は本発明に係る光磁気記録媒体の実施例の断
面構成図を示す。ガラス基板１上に、パーマロイ等のNi
Fe合金から成る、厚さ1000Åの高透磁率磁性体層２が形
成され、この上にCoCr合金膜（組成:CO85CO15）等の垂
直磁化膜から成り、高さ約3000Åで幅約4000Åの台形状
凸部３が、約１μｍピッチで形成され、これらの上に第
二の垂直磁化膜から成る記録層４として、厚さ3000Åの
TbFeCo合金膜（組成:Tb0.22（Fe0.9Co0.1）0.78）さら
に、保護層５として屈折率2.0、厚さ800ÅのSi3N4膜の
順に形成されている。(Example) Next, the Example of this invention is described in detail using drawing. FIG. 1 shows a cross-sectional configuration diagram of an embodiment of a magneto-optical recording medium according to the present invention. Ni such as permalloy is placed on the glass substrate 1.
A high-permeability magnetic layer 2 with a thickness of 1000Å made of Fe alloy is formed, and a perpendicular magnetic film such as a CoCr alloy film (composition: CO 85 CO 15 ) is formed on the magnetic layer 2, and the height is about 3000Å and the width is about 4000Å. Trapezoidal protrusions 3 are formed at a pitch of about 1 μm, and a recording layer 4 made of a second perpendicular magnetization film has a thickness of 3000 Å.
TbFeCo alloy film (composition: Tb 0.22 (Fe 0.9 Co 0.1 ) 0.78 ) Further, as the protective layer 5, a Si 3 N 4 film having a refractive index of 2.0 and a thickness of 800 Å is formed in this order.
各層は、マグネトロンスパッタにより成膜される。ま
ず、CoCr合金膜から成る台形状凸部２は次の様にして形
成される。ガラス基板に、厚さ1000ÅのNiFe合金膜を成
膜し、次にCoCr合金ターゲットを用いて、Arガス雰囲気
で、パワー密度4W/cm2、スパッタガス圧3.5×10-1Pa
で、CoCr膜を3000Åの厚さにスパッタした後、第２図
（ａ）に示す様に、厚さ2000Å、幅5000Åのレジストパ
ターン６を１μｍピッチで形成し、Arを用いてガス圧2.
6×10-2Paで12分間イオンミリングする。さらに、酸素
プラズマにより残ったレジストを、はく離することによ
って、第２図（ｂ）に示す様に、高さ3000Å、幅4000Å
のCoCr膜から成る台形状凸部３が、約１μｍピッチで形
成される。記録層4TbFeCo合金膜は、FeCoターゲット上
にTb片を配した複合ターゲットを用い、Arガス雰囲気
で、パワー密度4W/cm2、スパッタガス圧3.5×10-1Paで
作製される。保護層5Si3N4膜は、Siターゲットを用い、
ArとN2の混合ガス（4.55％N2）をスパッタガスとした反
応性スパッタによりパワー密度2.2W/cm2、スパッタガス
圧8.3×10-2Paで、作製される。Each layer is formed by magnetron sputtering. First, the trapezoidal convex portion 2 made of a CoCr alloy film is formed as follows. A 1000Å-thick NiFe alloy film is formed on a glass substrate, and then a CoCr alloy target is used in an Ar gas atmosphere with a power density of 4 W / cm 2 and a sputtering gas pressure of 3.5 × 10 -1 Pa.
Then, after sputtering the CoCr film to a thickness of 3000Å, as shown in FIG. 2 (a), a resist pattern 6 having a thickness of 2000Å and a width of 5000Å is formed at a pitch of 1 μm, and a gas pressure of 2. is used by using Ar.
Ion mill for 12 minutes at 6 × 10 -2 Pa. Further, by peeling off the resist remaining by the oxygen plasma, as shown in FIG. 2 (b), the height is 3000 Å and the width is 4000 Å
The trapezoidal convex portions 3 made of the CoCr film are formed at a pitch of about 1 μm. The recording layer 4TbFeCo alloy film is formed using a composite target in which Tb pieces are arranged on a FeCo target, in an Ar gas atmosphere, with a power density of 4 W / cm 2 and a sputtering gas pressure of 3.5 × 10 -1 Pa. The protective layer 5Si 3 N 4 film uses a Si target,
It is produced by reactive sputtering using a mixed gas of Ar and N 2 (4.55% N 2 ) as a sputtering gas at a power density of 2.2 W / cm 2 and a sputtering gas pressure of 8.3 × 10 -2 Pa.
次に、本発明による光磁気記録媒体を用いた記録動作
を、第３図を用いて説明する。本媒体の垂直磁化膜（Co
Cr合金膜）から成る凸部３と第２の垂直磁化膜（TbFeCo
合金膜）から成る記録層４を同じ垂直方向（＋ｙの向
き）に、あらかじめ着磁しておくことによって、第３図
（ａ）に示す様に記録層は一定の向きに初期着磁８され
る。またこれらの凸部の間にある記録層には、突起を成
すCoCr合金膜の磁化によって、それらの磁化とは逆向き
（−ｙの向き）バイアス磁界９を印加することができ
る。従って、第３図（ｂ）に示す様に、初期着磁と逆向
き（−ｙの向き）に着磁するタイミングにあわせて、レ
ーザビーム11を、前記凸部の間にある記録層部分に照射
して記録層の温度をキュリ温度以上（220℃）に上昇す
るだけで、冷却過程で所望の反転磁圧10を形成すること
ができる。Next, a recording operation using the magneto-optical recording medium according to the present invention will be described with reference to FIG. Perpendicular magnetization film (Co
The protrusion 3 made of a Cr alloy film and the second perpendicular magnetization film (TbFeCo)
By pre-magnetizing the recording layer 4 made of an alloy film in the same vertical direction (+ y direction), the recording layer is initially magnetized 8 in a fixed direction as shown in FIG. 3 (a). It A bias magnetic field 9 in the opposite direction (−y direction) to the magnetization can be applied to the recording layer between these protrusions by the magnetization of the CoCr alloy film forming the protrusion. Therefore, as shown in FIG. 3 (b), the laser beam 11 is directed to the recording layer portion between the convex portions in accordance with the timing of magnetization in the direction opposite to the initial magnetization (direction of -y). Only by irradiating and raising the temperature of the recording layer to above the Curie temperature (220 ° C.), the desired reversal magnetic pressure 10 can be formed in the cooling process.
ここで、凸部を成す垂直磁化膜の高さ及びピッチ等の形
状及び膜組成並びに、高透磁率磁性体層の厚さは、上述
のものに限定されるものではなく、所望の記録媒体の記
録密度及びバイアス磁界の大きさに応じて、適宜選定さ
れる。凸部の高さとしては数十オングストローム、ピッ
チとしては、１μｍ前後が好ましい。凸部の膜組成はCo
Cr合金膜以外に、バリウムフェライトの垂直磁化膜でも
良い。また、記録層の組成も上述のものに限定されるも
のではなく、抗磁力Hcが、上記凸部からのバイアス磁界
より大きくできる範囲で、他の光磁気記録材料を選定し
ても良い。誘電体が成る保護層としては、Si3N4の他にA
lN,SiO2,SiO等を、数百Å〜数千Åの厚さに形成したも
のが用いられる。Here, the shape and film composition such as the height and pitch of the perpendicularly magnetized film forming the convex portion and the thickness of the high magnetic permeability magnetic layer are not limited to those described above, and the desired recording medium It is appropriately selected according to the recording density and the magnitude of the bias magnetic field. The height of the convex portions is preferably several tens of angstroms, and the pitch is preferably around 1 μm. The film composition of the protrusion is Co
A perpendicular magnetization film of barium ferrite may be used instead of the Cr alloy film. Also, the composition of the recording layer is not limited to the above-mentioned one, and other magneto-optical recording material may be selected within a range in which the coercive force Hc can be larger than the bias magnetic field from the convex portion. In addition to Si 3 N 4 , the protective layer consisting of a dielectric
It is used that has a thickness of several hundred Å to several thousand Å made of lN, SiO 2 , SiO and the like.
（発明の効果） 以上述べた様に、本発明によれば、一方向のバイアス磁
界印加手段を内蔵した光磁気記録媒体を提供できる。従
って、記録層をあらかじめ第１の垂直磁化膜と同一方向
に初期着磁しておけば、外部磁界印加手段を必要とせず
に、レーザビームの昇温だけで、反転磁圧の形成ができ
る。また、本媒体と、バイアス磁界と逆方向にだけ磁界
をスイッチングできる外部磁界印加手段を用いて、一定
レーザビームを照射しながら、前記バイアス磁界を外部
磁界印加手段からの磁界を組み合わせた磁界変調による
記録も容易になる。また、基体と垂直磁化膜から成る突
起の間に設けた高透磁率磁性体層は、上記バイアス磁界
を記録領域に効率良く導く働きがある。(Effects of the Invention) As described above, according to the present invention, it is possible to provide a magneto-optical recording medium incorporating a unidirectional bias magnetic field applying means. Therefore, if the recording layer is initially magnetized in the same direction as the first perpendicular magnetization film in advance, the reversal magnetic pressure can be formed only by raising the temperature of the laser beam without the need for an external magnetic field applying means. Further, by using this medium and an external magnetic field applying means capable of switching the magnetic field only in the direction opposite to the bias magnetic field, the bias magnetic field is modulated by a magnetic field modulation which combines the magnetic field from the external magnetic field applying means while irradiating a constant laser beam. Recording is also easy. Further, the high magnetic permeability magnetic layer provided between the substrate and the protrusion formed of the perpendicular magnetization film has a function of efficiently guiding the bias magnetic field to the recording region.
第１図は本発明の実施例を示す図、第２図は本発明の作
製法を示す図、第３図は、本発明の動作を説明する図で
ある。 図において、１……基板、２……高透磁率磁性体層、３
……垂直磁化膜から成る凸部、４……記録層、５……保
護層、６……レジストパターン、７……凸部内の磁化、
８……初期着磁・磁化、９……凸部内磁化からのバイア
ス磁界、10……反転磁化、11……レーザビームである。FIG. 1 is a diagram showing an embodiment of the present invention, FIG. 2 is a diagram showing a manufacturing method of the present invention, and FIG. 3 is a diagram explaining an operation of the present invention. In the figure, 1 ... Substrate, 2 ... High-permeability magnetic material layer, 3
...... Convex part consisting of perpendicular magnetization film, 4 ... Recording layer, 5 ... Protective layer, 6 ... Resist pattern, 7 ... Magnetization in convex part,
8 ... Initial magnetization / magnetization, 9 ... Bias magnetic field from magnetization in convex portion, 10 ... Inverted magnetization, 11 ... Laser beam.
Claims (2)
この上に、膜面に垂直方向に、磁気異方性を有する第１
の垂直磁化膜から成る環状の凸部が、一定間隔で形成さ
れ、次に、第２の垂直磁化膜から成る記録層、誘電体か
ら成る保護層の順に形成され、更に前記第１及び第２の
垂直磁化膜が同一方向に着磁されることを特徴とする光
磁記録媒体。1. A high magnetic permeability magnetic layer is formed on a substrate,
On top of this, a first layer having magnetic anisotropy in the direction perpendicular to the film surface.
Annular convex portions made of the perpendicular magnetic film are formed at regular intervals, and then a recording layer made of the second perpendicular magnetic film and a protective layer made of a dielectric are formed in this order, and further, the first and second 2. The magneto-optical recording medium, wherein the perpendicularly magnetized films of 1. are magnetized in the same direction.
非晶質磁性合金薄膜である特許請求の範囲第１項に記載
の光磁気記録媒体。2. A recording layer comprising the second perpendicular magnetization film,
The magneto-optical recording medium according to claim 1, which is an amorphous magnetic alloy thin film.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP30079986A JPH0673199B2 (en) | 1986-12-16 | 1986-12-16 | Magneto-optical recording medium |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP30079986A JPH0673199B2 (en) | 1986-12-16 | 1986-12-16 | Magneto-optical recording medium |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS63152048A JPS63152048A (en) | 1988-06-24 |
| JPH0673199B2 true JPH0673199B2 (en) | 1994-09-14 |
Family
ID=17889238
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP30079986A Expired - Lifetime JPH0673199B2 (en) | 1986-12-16 | 1986-12-16 | Magneto-optical recording medium |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0673199B2 (en) |
-
1986
- 1986-12-16 JP JP30079986A patent/JPH0673199B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPS63152048A (en) | 1988-06-24 |
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