JPH0744915A - Production of magneto-optical recording medium - Google Patents
Production of magneto-optical recording mediumInfo
- Publication number
- JPH0744915A JPH0744915A JP18515493A JP18515493A JPH0744915A JP H0744915 A JPH0744915 A JP H0744915A JP 18515493 A JP18515493 A JP 18515493A JP 18515493 A JP18515493 A JP 18515493A JP H0744915 A JPH0744915 A JP H0744915A
- Authority
- JP
- Japan
- Prior art keywords
- layer
- film
- transition metal
- artificial lattice
- 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.)
- Pending
Links
Abstract
Description
【0001】[0001]
【産業上の利用分野】本発明は光を用い情報の記録、再
生、消去を行う光磁気記録媒体の製造方法に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a magneto-optical recording medium which records, reproduces and erases information by using light.
【0002】[0002]
【従来の技術】光磁気記録媒体を高密度化する手段のひ
とつとして、記録再生に短波長の光源を用いる方法があ
り、このような方法に用いる媒体として、短波長域で大
きな磁気光学効果を示す、Co層とPt層を交互に積層
した人工格子膜を用いた光磁気記録媒体が提案されてい
る。またこの人工格子膜の保磁力の小ささ、ノイズレベ
ルが高いことを補うために、希土類遷移金属合金層と磁
気的に交換結合した積層膜も提案されている。しかしな
がら、このような交換結合膜をスパッタ法等により成膜
すると、人工格子膜の各層の層厚の分布やカラム構造な
どに起因して、交換結合力の大きさが一定にならず、ば
らつきが大きいために、記録特性の制御が困難になると
いう問題があった。2. Description of the Related Art As one of means for increasing the density of a magneto-optical recording medium, there is a method of using a light source of short wavelength for recording / reproducing. As a medium used for such a method, a large magneto-optical effect in a short wavelength region is obtained. A magneto-optical recording medium using an artificial lattice film in which Co layers and Pt layers are alternately laminated has been proposed. In order to compensate for the low coercive force and high noise level of this artificial lattice film, a laminated film magnetically exchange-coupled with the rare earth-transition metal alloy layer has also been proposed. However, when such an exchange coupling film is formed by a sputtering method or the like, the magnitude of the exchange coupling force is not constant due to the layer thickness distribution of each layer of the artificial lattice film, the column structure, etc., and variations occur. Since it is large, there is a problem that it is difficult to control the recording characteristics.
【0003】[0003]
【発明が解決しようとする課題】本発明の目的は、上記
課題を解決し、人工格子膜と希土類遷移金属合金層との
良好に制御された磁気的結合力を得る光磁気記録媒体を
提供することを目的とする。SUMMARY OF THE INVENTION An object of the present invention is to solve the above problems and provide a magneto-optical recording medium having a well-controlled magnetic coupling force between an artificial lattice film and a rare earth transition metal alloy layer. The purpose is to
【0004】[0004]
【課題を解決するための手段】本発明者らは上記目的達
成のために鋭意研究を重ねた結果、基板上で人工格子膜
と希土類遷移金属合金層を成膜する際、人工格子膜層を
逆スパッタした後希土類遷移金属合金層を成膜すると、
これらの膜どうしの磁気的結合力の制御が容易になり、
交換結合力が均一で記録特性が安定した光磁気記録媒体
を得ることを見出した。Means for Solving the Problems As a result of intensive studies for achieving the above object, the present inventors have found that when forming an artificial lattice film and a rare earth transition metal alloy layer on a substrate, the artificial lattice film layer is formed. When a rare earth transition metal alloy layer is formed after reverse sputtering,
It becomes easy to control the magnetic coupling force between these films,
It has been found that a magneto-optical recording medium having a uniform exchange coupling force and stable recording characteristics can be obtained.
【0005】即ち本発明は、基板上にFe、Co、Ni
のうちから選ばれる少な姦と癌一つの元素から主とし監
なる層(遷移金属層)と、Ptお頑び運又はPdから主
としてなる冽(貴金属層)とを積層してなる人工格子膜
と、希土滿遷移金属合金層の少なくとも一冽と嬉磁気的
に結合して積冽し監な企膜嬉記濘層とする光磁気記録区
媒厠の仆造曄に於いて、成膜した人工格子膜を逆スパッ
タし、その後に希土類遷移金属合金層を成膜することを
特徴とする光磁気記録媒体の製造方法に関するものであ
る。That is, according to the present invention, Fe, Co, Ni are formed on the substrate.
An artificial lattice film formed by laminating a layer (transition metal layer) mainly composed of one element of cancer and a cancer (precious metal layer) composed mainly of Pd or Pd. , A rare earth-transition metal alloy layer was magnetically coupled with at least one magnetic layer, and was formed into a thin film. The present invention relates to a method for manufacturing a magneto-optical recording medium, which comprises performing reverse sputtering on an artificial lattice film and then forming a rare earth-transition metal alloy layer.
【0006】次に本発明で得られた光磁気記録媒体の例
を図面により更に説明する。Next, an example of the magneto-optical recording medium obtained by the present invention will be further described with reference to the drawings.
【0007】図1は本発明で得た記録媒体の一実施様態
を示す図である。図中1は透明基板であり、通常高分子
基板やガラス基板が用いられる。図中2は透明誘電体層
であり、SiN、ZnS、AlNなどを用いることがで
きる。図中3は人工格子膜で、遷移金属層(図中3−
1)と貴金属層(図中3−2)とからなる。図中4は希
土類遷移金属層、図中5は保護膜である。FIG. 1 is a diagram showing an embodiment of a recording medium obtained by the present invention. In the figure, 1 is a transparent substrate, and a polymer substrate or a glass substrate is usually used. In the figure, 2 is a transparent dielectric layer, and SiN, ZnS, AlN or the like can be used. Reference numeral 3 in the figure denotes an artificial lattice film, which is a transition metal layer (3-
1) and a noble metal layer (3-2 in the figure). In the figure, 4 is a rare earth transition metal layer, and 5 is a protective film.
【0008】本発明において、上記した記録媒体の各層
の形成は、通常の薄膜形成法であるスパッタ法や蒸着法
を用いることができる。又、人工格子膜の積層は遷移金
属層、貴金属層を通常は交互に積層するが、その順序は
遷移金属層から積層しても貴金属層から積層しても良い
(図1では遷移金属層から積層しぞ例を示した)。In the present invention, each layer of the above-mentioned recording medium can be formed by a usual thin film forming method such as a sputtering method or a vapor deposition method. Further, in the lamination of the artificial lattice film, the transition metal layer and the noble metal layer are usually laminated alternately, but the order may be laminated from the transition metal layer or the noble metal layer (in FIG. 1, the transition metal layer is laminated). An example of a laminated groove is shown).
【0009】この人工格子膜を構成する遷移金属層は、
Fe、Co、Niのうちから選ばれる少なくとも一つの
元素から主としてなる層で、その厚さは2〜8Aの厚さ
であることが好適である。この厚さが2Aよりも薄いと
十分なカー回転角が得られなくなり、8オングストロー
ムよりも厚いと十分な垂直磁気異方性が得られなくな
る。またPtおよび/又はPdから主としてなる貴金属
層の厚さは4〜20オングストロームの範囲が好適であ
る。その厚さが4オングストロームよりも薄いと好適な
垂直磁気異方性が得られなくなり、20オングストロー
ムよりも厚いとカー回転角が低下する。The transition metal layer constituting this artificial lattice film is
It is a layer mainly composed of at least one element selected from Fe, Co and Ni, and the thickness thereof is preferably 2 to 8A. If this thickness is thinner than 2 A, a sufficient Kerr rotation angle cannot be obtained, and if it is thicker than 8 Å, sufficient perpendicular magnetic anisotropy cannot be obtained. Further, the thickness of the noble metal layer mainly composed of Pt and / or Pd is preferably in the range of 4 to 20 angstrom. When the thickness is less than 4 angstroms, suitable perpendicular magnetic anisotropy cannot be obtained, and when it is more than 20 angstroms, the Kerr rotation angle decreases.
【0010】本発明の方法では、人工格子膜の成膜後に
その面を対象に逆スパッタを行い、その後希土類遷移金
属層を成膜する事が特徴であるが、逆スパッタの条件
は、人工格子膜がスパッタされすべてとり去られない条
件、あるいは残った人工格子膜のすべてが均一な合金層
とならない条件であればよい。The method of the present invention is characterized in that after the artificial lattice film is formed, reverse sputtering is performed on the surface of the artificial lattice film, and then a rare earth transition metal layer is formed. It is only necessary that the film is sputtered and not all removed, or that all of the remaining artificial lattice film does not form a uniform alloy layer.
【0011】その際、逆スパッタによって、人工格子膜
の一部において遷移金属層と貴金属層との界面において
混合層が形成されてもよい。又、目的によっては、人工
格子膜の成膜において最後に積層される層として貴金属
層を成膜し、この厚さを変化させることによって適宜交
換結合力の制御をすることも可能であるが、この場合で
も安定した交換結合力を有した記録膜を再現性良く作成
できる。At this time, a mixed layer may be formed at the interface between the transition metal layer and the noble metal layer in a part of the artificial lattice film by reverse sputtering. Further, depending on the purpose, it is possible to form a noble metal layer as the last layer to be laminated in the formation of the artificial lattice film and change the thickness to appropriately control the exchange coupling force. Even in this case, a recording film having a stable exchange coupling force can be produced with good reproducibility.
【0012】逆スパッタを行った後、TbFe、TbF
eCo、DyFeCo、GdDyFeCo、NdGdF
eCo等からなる希土類遷移金属層を成膜する。After performing reverse sputtering, TbFe, TbF
eCo, DyFeCo, GdDyFeCo, NdGdF
A rare earth transition metal layer made of eCo or the like is formed.
【0013】ところで、2つの垂直磁気異方性を持つ層
の界面に於ける磁気的交換結合エネルギーはそれぞれの
層の磁化反転を示すマイナーループの零点からの磁界シ
フト量に比例する。本発明の方法で得られた記録媒体の
場合単位面積当たりの交換結合エネルギーσwは磁気ヒ
ステリシスループから式(1)によって求められる。 σw=2・M・d・ΔH (1) ここでMは人工格子膜の単位体積当たりの飽和磁化、d
は人工格子膜の膜厚、ΔHは磁気ヒステリシスループの
人工格子膜の磁化のマイナーループの零点からのシフト
磁界の大きさである。従って、マイナーループのシフト
量を測定することによって交換結合エネルギーが所定の
大きさであるかを調べることができる。人工格子膜の磁
化のマイナーループがシフトすることによって、人工格
子膜の保磁力が実質的に増大、あるいは減少させること
ができる。The magnetic exchange coupling energy at the interface between two layers having perpendicular magnetic anisotropy is proportional to the amount of magnetic field shift from the zero point of the minor loop indicating the magnetization reversal of each layer. In the case of the recording medium obtained by the method of the present invention, the exchange coupling energy σ w per unit area is obtained from the magnetic hysteresis loop by the equation (1). σ w = 2 · M · d · ΔH (1) where M is the saturation magnetization per unit volume of the artificial lattice film, d
Is the film thickness of the artificial lattice film, and ΔH is the magnitude of the shift magnetic field from the zero point of the minor loop of the magnetization of the artificial lattice film of the magnetic hysteresis loop. Therefore, by measuring the shift amount of the minor loop, it is possible to check whether the exchange coupling energy has a predetermined magnitude. The coercive force of the artificial lattice film can be substantially increased or decreased by shifting the minor loop of the magnetization of the artificial lattice film.
【0014】光磁気記録媒体においては保磁力の実質的
増大によって、記録ピットの一層の安定化を計ることが
できる。In the magneto-optical recording medium, the recording pit can be further stabilized by substantially increasing the coercive force.
【0015】[0015]
【実施例】次に、実施例で本発明を更に詳述する。 実施例1 CoのターゲットとPtのターゲットを用い、5枚のガ
ラス基板(1−1〜5)を取り付けた基板ホルダーがそ
の上を基板が順次通過するようにしながらrfマグネト
ロンスパッタリングにより成膜した。スパッタリングは
5 mToorのAr雰囲気で行った。まず、Pt層から成膜
を始め、10Aの厚さのPt層および3.5Aの厚さの
Co層を各9回成膜した。次に、300Wのrfパワー
で1分間、逆スパッタした。引き続きTbFeCoター
ゲットをスパッタして、800AのTbFeCoを成膜
した。EXAMPLES Next, the present invention will be described in more detail with reference to Examples. Example 1 A Co target and a Pt target were used, and a film was formed by rf magnetron sputtering while a substrate holder to which five glass substrates (1-1 to 5) were attached so that the substrates sequentially passed therethrough. Sputtering was performed in an Ar atmosphere of 5 mToor. First, the film formation was started from the Pt layer, and the Pt layer having a thickness of 10 A and the Co layer having a thickness of 3.5 A were formed 9 times each. Next, reverse sputtering was performed at an rf power of 300 W for 1 minute. Subsequently, a TbFeCo target was sputtered to form a 800 A TbFeCo film.
【0016】得られた膜の磁気ヒステリシスループを振
動試料磁力計を用いて測定し図2に示した(尚、縦軸に
磁化、横軸に外部磁界を示す)。ヒステリシスループは
二段型のループを示した。人工格子の磁化の変化を示す
マイナーループを測定したところ、ループの中心の磁界
の零点からのシフトはそれぞれ次に示した通りであっ
た。 試料名 1−1 1−2 1−3 1−4 1−5 シフト量 3.2 3.2 3.3 3.3 3.2 (KOe) 実施例2 実施例1と同様にして、5枚のガラス基板上(2−1〜
5)に、同様のスパッタ条件で人工格子膜を成膜した
後、成膜装置に大気を導入し大気圧とした。次に、真空
に排気したのち、Arガスを導入して、逆スパッタを実
施例1と同様に行い、引き続きTbFeCo層を成膜し
た。得られた5つの試料における人工格子膜のマイナー
ループのシフト量はそれぞれ次に示した通りであった。 試料名 2−1 2−2 2−3 2−4 2−5 シフト量 3.0 2.9 3.1 3.0 3.1 (KOe) 比較例1 実施例1と同様に人工格子膜を成膜した後、逆スパッタ
を実施せずTbFeCo層を成膜した。得られた5つの
膜の人工格子膜(3−1〜5)のマイナーループのシフ
ト量はそれぞれ次に示した通りであった。 試料名 3−1 3−2 3−3 3−4 3−5 シフト量 2.4 2.1 2.6 2.3 2.0 (KOe) 比較例2 実施例1と同様に人工格子膜を成膜した後、成膜装置に
大気を導入し大気圧とした。再び真空にし、Arガスを
導入して、逆スパッタせずにTbFeCo層を成膜し
た。得られた5つの膜の人工格子膜(4−1〜5)のマ
イナーループのシフト量はそれぞれ次に示した通りであ
った。 試料名 4−1 4−2 4−3 4−4 4−5 シフト量 0.1 0.4 0.5 0.4 0.3 (KOe) The magnetic hysteresis loop of the obtained film was measured using a vibrating sample magnetometer and is shown in FIG. 2 (the ordinate represents the magnetization and the abscissa represents the external magnetic field). The hysteresis loop showed a two-stage loop. When the minor loop showing the change of the magnetization of the artificial lattice was measured, the shift of the magnetic field at the center of the loop from the zero point was as shown below. Sample name 1-1 1-2 1-3 1-3 1-4 1-5 shift amount 3.2 3.2 3.3 3.3 3.2 (KOe) Example 2 5 sheets in the same manner as Example 1. On the glass substrate (2-1 ~
In 5), an artificial lattice film was formed under the same sputtering conditions, and then atmospheric air was introduced into the film forming apparatus to bring it to atmospheric pressure. Next, after evacuation to vacuum, Ar gas was introduced and reverse sputtering was performed in the same manner as in Example 1, and subsequently a TbFeCo layer was formed. The shift amounts of the minor loops of the artificial lattice film in the five obtained samples were as shown below. Sample name 2-1 2-2 2-3 2-4 2-5 Shift amount 3.0 2.9 3.1 3.0 3.1 (KOe) Comparative Example 1 An artificial lattice film was prepared in the same manner as in Example 1. After forming the film, the TbFeCo layer was formed without performing reverse sputtering. The amounts of shifts of the minor loops of the obtained artificial lattice films (3-1 to 5) of the five films were as shown below. Sample name 3-1 3-2 3-3 3-4 3-5 Shift amount 2.4 2.1 2.6 2.3 2.0 (KOe) Comparative Example 2 An artificial lattice film was prepared in the same manner as in Example 1. After forming the film, the atmosphere was introduced into the film forming apparatus to set the atmospheric pressure. The vacuum was again applied, Ar gas was introduced, and a TbFeCo layer was formed without performing reverse sputtering. The shift amounts of the minor loops of the obtained artificial lattice films (4-1 to 5) of the five films were as shown below. Sample name 4-1 4-2 4-3 4-4 4-5 Shift amount 0.1 0.4 0.5 0.4 0.3 (KOe)
【0017】[0017]
【発明の効果】以上説明した通り、本発明で得た光磁気
記録媒体は、人工格子膜と希土類遷移金属層との磁気的
交換結合力の制御性に優れており、安定した磁気特性を
有した光磁気記録媒体であり、良好な記録再生特性が期
待できるものである。As described above, the magneto-optical recording medium obtained by the present invention has excellent controllability of the magnetic exchange coupling force between the artificial lattice film and the rare earth transition metal layer, and has stable magnetic characteristics. The above magneto-optical recording medium is expected to have good recording / reproducing characteristics.
【図1】本発明で得た光磁気記録媒体の一実施態様を示
す図。FIG. 1 is a diagram showing an embodiment of a magneto-optical recording medium obtained by the present invention.
【図2】実施例1で得た記録媒体の磁気ヒステリシスル
ープを示す図。FIG. 2 is a diagram showing a magnetic hysteresis loop of the recording medium obtained in Example 1.
1:透明基板 2:誘電体層 3:人工格子膜 3−1:遷移金属層 3−2:貴金属層 4:希土類遷移金属層 1: Transparent substrate 2: Dielectric layer 3: Artificial lattice film 3-1: Transition metal layer 3-2: Noble metal layer 4: Rare earth transition metal layer
─────────────────────────────────────────────────────
─────────────────────────────────────────────────── ───
【手続補正書】[Procedure amendment]
【提出日】平成5年8月5日[Submission date] August 5, 1993
【手続補正1】[Procedure Amendment 1]
【補正対象書類名】明細書[Document name to be amended] Statement
【補正対象項目名】0005[Name of item to be corrected] 0005
【補正方法】変更[Correction method] Change
【補正内容】[Correction content]
【0005】即ち本発明は、基板上にFe、Co、Ni
のうちから選ばれる少なくとも一つの元素から主として
なる層(遷移金属層)と、Ptおよび/又はPdから主
としてなる層(貴金属層)とを積層してなる人工格子膜
と、希土類遷移金属合金層の少なくとも一層とを磁気的
に結合して積層してなる膜を記録層とする光磁気記録媒
体の製造法に於いて、成膜した人工格子膜を逆スパッタ
し、その後に希土類遷移金属合金層を成膜することを特
徴とする光磁気記録媒体の製造方法に関するものであ
る。That is, according to the present invention, Fe, Co, Ni are formed on the substrate.
Formed by laminating a main and to <br/> comprising a layer (transition metal layer) mainly composed of a layer of Pt Contact good beauty / or Pd and (noble metal layer) from least for one of the elements are also selected from among the and an artificial lattice film, a magneto-optical recording medium to a magnetically coupled ing and product layer film and at least one layer of rare-earth transition metal alloy layer record layer
In the manufacturing method of the body, and reverse sputtering deposition artificial lattice film is then a method for manufacturing a magneto-optical recording medium, characterized by forming the rare earth-transition metal alloy layer.
【手続補正2】[Procedure Amendment 2]
【補正対象書類名】明細書[Document name to be amended] Statement
【補正対象項目名】0008[Correction target item name] 0008
【補正方法】変更[Correction method] Change
【補正内容】[Correction content]
【0008】本発明において、上記した記録媒体の各層
の形成は、通常の薄膜形成法であるスパッタ法や蒸着法
を用いることができる。又、人工格子膜の積層は遷移金
属層、貴金属層を通常は交互に積層するが、その順序は
遷移金属層から積層しても貴金属層から積層しても良い
(図1では遷移金属層から積層した例を示した)。In the present invention, each layer of the above-mentioned recording medium can be formed by a usual thin film forming method such as a sputtering method or a vapor deposition method. Further, in the lamination of the artificial lattice film, the transition metal layer and the noble metal layer are usually laminated alternately, but the order may be laminated from the transition metal layer or the noble metal layer (in FIG. 1, the transition metal layer is laminated). An example of stacking is shown).
Claims (2)
れる少なくとも一つの元素から主としてなる層と、Pt
および/又はPdから主としてなる層とを積層してなる
人工格子膜と、希土類遷移金属合金層の少なくとも一層
とを磁気的に結合して積層してなる膜を記録層とする光
磁気記録媒体の製造法に於いて、成膜した人工格子膜を
逆スパッタし、その後に希土類遷移金属合金層を成膜す
ることを特徴とする光磁気記録媒体の製造方法。1. A layer mainly composed of at least one element selected from Fe, Co and Ni, and Pt on a substrate.
A magneto-optical recording medium having an artificial lattice film, which is formed by laminating a layer mainly composed of Pd and / or Pd, and at least one layer of a rare earth transition metal alloy layer, which are magnetically coupled and laminated as a recording layer. A method for manufacturing a magneto-optical recording medium, characterized in that, in the manufacturing method, the formed artificial lattice film is reverse-sputtered, and then a rare earth transition metal alloy layer is formed.
層と4〜20Aの厚さのPt及び/またはPdからなる
層とを交互に2回以上積層し成膜したものである請求項
1記載の製造方法。2. An artificial lattice film, wherein a transition metal layer having a thickness of 2 to 8 A and a layer made of Pt and / or Pd having a thickness of 4 to 20 A are alternately laminated two or more times. The manufacturing method according to claim 1.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP18515493A JPH0744915A (en) | 1993-07-27 | 1993-07-27 | Production of magneto-optical recording medium |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP18515493A JPH0744915A (en) | 1993-07-27 | 1993-07-27 | Production of magneto-optical recording medium |
Publications (1)
Publication Number | Publication Date |
---|---|
JPH0744915A true JPH0744915A (en) | 1995-02-14 |
Family
ID=16165797
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP18515493A Pending JPH0744915A (en) | 1993-07-27 | 1993-07-27 | Production of magneto-optical recording medium |
Country Status (1)
Country | Link |
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JP (1) | JPH0744915A (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US7285105B2 (en) | 2000-06-15 | 2007-10-23 | Jms Co., Ltd | Automatic dialyzer and dialyzing method |
-
1993
- 1993-07-27 JP JP18515493A patent/JPH0744915A/en active Pending
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US7285105B2 (en) | 2000-06-15 | 2007-10-23 | Jms Co., Ltd | Automatic dialyzer and dialyzing method |
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