JPH08180360A - Perpendicular magnetic recording medium and magnetic recorder - Google Patents
Perpendicular magnetic recording medium and magnetic recorderInfo
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- JPH08180360A JPH08180360A JP31795194A JP31795194A JPH08180360A JP H08180360 A JPH08180360 A JP H08180360A JP 31795194 A JP31795194 A JP 31795194A JP 31795194 A JP31795194 A JP 31795194A JP H08180360 A JPH08180360 A JP H08180360A
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- film
- alloy
- recording medium
- magnetic recording
- underlayer
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Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、高密度磁気記録に適す
る磁性膜を備えた垂直磁気記録媒体及びそれを用いた磁
気記録装置に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a perpendicular magnetic recording medium provided with a magnetic film suitable for high density magnetic recording and a magnetic recording apparatus using the same.
【０００２】[0002]
【従来の技術】情報化社会の発展を背景に、大量の情報
を蓄積し、高速に入出力することのできる磁気記録装置
への要求はますます高まっている。より多くの情報をコ
ンパクトに記録するために、従来から用いられている面
内磁気記録方式に代わって、さらに記録密度を向上でき
る新たな記録方式として、垂直磁気記録方式が注目を集
めてきた。2. Description of the Related Art With the development of information-oriented society, there is an increasing demand for a magnetic recording device capable of accumulating a large amount of information and inputting / outputting at high speed. In order to compactly record more information, the perpendicular magnetic recording method has attracted attention as a new recording method that can further improve the recording density in place of the in-plane magnetic recording method that has been conventionally used.
【０００３】垂直磁気記録は、記録媒体の表面に対して
垂直方向に形成した磁化を記録単位とする記録方式で、
磁化反転部分で反磁界の影響が小さくなるため、高密度
記録に適していると考えられる。これはアイイーイーイ
ー トランザクションズ オン マグネティクス（IEEE
Transactions on Magnetics），ＭＡＧ−１３(1977)１
２７２頁の論文に記述されている。この垂直磁気記録に
用いる記録媒体は、媒体表面に垂直な方向に磁化容易軸
を持ち、かつ大きな磁気異方性を持つ必要がある。この
ため、基板上に垂直磁化膜を形成した薄膜媒体の研究開
発が行われてきた。Perpendicular magnetic recording is a recording system in which the magnetization formed in the direction perpendicular to the surface of the recording medium is used as a recording unit.
Since the influence of the demagnetizing field is small in the magnetization reversal portion, it is considered suitable for high density recording. This is IEE Transactions on Magnetics (IEEE
Transactions on Magnetics), MAG-13 (1977) 1
It is described in the article on page 272. The recording medium used for this perpendicular magnetic recording must have an easy axis of magnetization in the direction perpendicular to the medium surface and have a large magnetic anisotropy. For this reason, research and development have been conducted on thin film media in which a perpendicularly magnetized film is formed on a substrate.
【０００４】垂直磁気記録媒体の記録膜には、磁気異方
性の大きいＣｏ合金を用いることが、従来から検討され
てきた。ＣｏＣｒ合金等のＣｏ合金は、六方最密充填構
造を持ち、そのｃ軸を磁化容易軸とする一軸磁気異方性
を示す。ガラスなどの非晶質基板の表面に、Ｃｏ合金の
薄膜を形成すると、原子の最稠密面である(０００１)面
が基板面に平行になりやすく、［０００１］配向した多
結晶薄膜が得られる。この膜は、垂直磁気異方性を示す
が、垂直磁気記録媒体として用いるには、さらに大きな
磁気異方性を持たせることが必要であった。It has been conventionally studied to use a Co alloy having a large magnetic anisotropy for the recording film of the perpendicular magnetic recording medium. Co alloys such as CoCr alloys have a hexagonal close-packed structure and exhibit uniaxial magnetic anisotropy with the c-axis as the easy axis of magnetization. When a Co alloy thin film is formed on the surface of an amorphous substrate such as glass, the (0001) plane, which is the closest packed atom plane, tends to be parallel to the substrate surface, and a [0001] oriented polycrystalline thin film is obtained. . Although this film exhibits perpendicular magnetic anisotropy, it was necessary to have a larger magnetic anisotropy in order to use it as a perpendicular magnetic recording medium.
【０００５】そこで、基板上に下地膜を設けて、Ｃｏ合
金磁性膜のｃ軸配向性を向上させる試みがなされてき
た。Ｔｉ等の六方最密充填構造を持つ薄膜は、［０００
１］配向しやすいため、これを下地膜として用い、Ｃｏ
合金磁性膜の配向性を改善できることが報告されてい
る。Ｔｉ下地膜を用いた垂直磁気記録媒体に関しては、
IEEE Transactions on Magnetics，ＭＡＧ−１９(１９
８３)１６４４頁に記載の論文に記述されている。Therefore, attempts have been made to improve the c-axis orientation of the Co alloy magnetic film by providing a base film on the substrate. A thin film having a hexagonal close-packed structure such as Ti is [000
1] Since it is easily oriented, it is used as a base film and Co
It has been reported that the orientation of the alloy magnetic film can be improved. Regarding a perpendicular magnetic recording medium using a Ti underlayer,
IEEE Transactions on Magnetics, MAG-19 (19
83) p. 1644.
【０００６】ところが、このようなＴｉ下地膜上に形成
したＣｏ合金磁性膜のｃ軸の分散の大きさも、十分小さ
いとはいえなかった。この原因は、ＴｉとＣｏ合金の格
子定数の差が１５％と大きいため、Ｃｏ合金の初期成長
時に配向性が乱れるためであると考えられる。そこで、
Ｃｏ合金磁性膜のｃ軸配向性をさらに向上させるための
新たな下地膜の開発が望まれていた。However, the magnitude of the c-axis dispersion of the Co alloy magnetic film formed on the Ti underlayer has not been sufficiently small. It is considered that this is because the difference between the lattice constants of Ti and Co alloy is as large as 15%, and the orientation is disturbed during the initial growth of Co alloy. Therefore,
It has been desired to develop a new undercoating film for further improving the c-axis orientation of the Co alloy magnetic film.
【０００７】[0007]
【発明が解決しようとする課題】本発明の目的は、従来
の下地膜上に形成したＣｏ合金膜に比べて、さらに結晶
配向性に優れ、垂直磁気異方性の大きな、垂直磁気記録
媒体を提供すること、及びそれを用いた磁気記録装置を
提供することにある。An object of the present invention is to provide a perpendicular magnetic recording medium which is more excellent in crystal orientation and has a large perpendicular magnetic anisotropy as compared with a conventional Co alloy film formed on a base film. It is to provide and a magnetic recording device using the same.
【０００８】[0008]
【課題を解決するための手段】本発明の垂直磁気記録媒
体は、図１に示すように、非磁性基板１１と，基板上に
形成された下地膜１２と，下地膜上に形成されたＣｏを
主成分とする合金の垂直磁化膜１３と，垂直磁化膜上に
形成された保護膜１４とからなる垂直磁気記録媒体であ
って、下地膜の材料がＣｏとＲｕの合金であることを特
徴とする。As shown in FIG. 1, a perpendicular magnetic recording medium of the present invention comprises a non-magnetic substrate 11, a base film 12 formed on the substrate, and a Co film formed on the base film. A perpendicular magnetic recording medium comprising a perpendicularly magnetized film 13 of an alloy containing as a main component and a protective film 14 formed on the perpendicularly magnetized film, wherein the material of the underlayer is an alloy of Co and Ru. And
【０００９】本発明の垂直磁気記録媒体の第二の特徴
は、図２に示すように、非磁性基板２１と，基板上に形
成された第一の下地膜２２と，第一の下地膜上に形成さ
れた第二の下地膜２３と，第二の下地膜上に形成された
Ｃｏを主成分とする合金の垂直磁化膜２４と，垂直磁化
膜上に形成された保護膜２５とからなる垂直磁気記録媒
体であって、第一の下地膜がＴｉまたはＲｕのいずれか
からなり、第二の下地膜がＣｏとＲｕの合金からなるこ
とにある。The second feature of the perpendicular magnetic recording medium of the present invention is, as shown in FIG. 2, a non-magnetic substrate 21, a first underlayer film 22 formed on the substrate, and a first underlayer film. A second underlayer film 23 formed on the second underlayer film, a perpendicular magnetization film 24 of an alloy containing Co as a main component formed on the second underlayer film, and a protective film 25 formed on the perpendicular magnetization film. In the perpendicular magnetic recording medium, the first underlayer film is made of either Ti or Ru, and the second underlayer film is made of an alloy of Co and Ru.
【００１０】本発明の第二の構成の垂直磁気記録媒体で
は、（１）ＣｏとＲｕの合金からなる下地膜が、Ｒｕの
濃度の異なる二層の膜からなり、垂直磁化膜の直下に位
置する層のＲｕ濃度が、この層の直下に位置する層のＲ
ｕ濃度よりも小さいこと、（２）ＣｏとＲｕの合金から
なる下地膜で、Ｒｕの濃度が、基板に近い側から垂直磁
化膜側に向かって、連続的に低下していること、のいず
れかを満足する構成としてもよい。In the perpendicular magnetic recording medium having the second structure of the present invention, (1) the underlayer film made of an alloy of Co and Ru is composed of two layers having different Ru concentrations, and is located immediately below the perpendicular magnetization film. The Ru concentration of the layer
It is smaller than the u concentration, or (2) the Ru film concentration is continuously decreased from the side close to the substrate to the side of the perpendicular magnetization film in the base film made of an alloy of Co and Ru. It may be configured to satisfy that.
【００１１】本発明の第一，第二の構成の垂直磁気記録
媒体では、ＣｏとＲｕの合金からなる下地膜は、Ｒｕの
濃度が４０ａｔ％Ｒｕ以上であることに特徴がある。The perpendicular magnetic recording medium of the first and second configurations of the present invention is characterized in that the underlying film made of an alloy of Co and Ru has a Ru concentration of 40 at% Ru or more.
【００１２】また本発明の第一，第二の構成の垂直磁気
記録媒体では、垂直磁化膜１３及び２４と，下地膜１
２，２２、及び２３がいずれも［０００１］優先方位配
向をしていることに特徴がある。Further, in the perpendicular magnetic recording medium of the first and second configurations of the present invention, the perpendicular magnetization films 13 and 24 and the base film 1 are used.
Each of 2, 22, and 23 is characterized by having a [0001] preferential azimuth orientation.
【００１３】さらに本発明の第一，第二の構成の垂直磁
気記録媒体では、基板１１及び２１の表面に微細な起伏
を設けた構成としてもよい。Further, the perpendicular magnetic recording medium of the first and second configurations of the present invention may have a configuration in which fine undulations are provided on the surfaces of the substrates 11 and 21.
【００１４】本発明の磁気記録装置は、上記で説明した
第一，第二の構成による垂直磁気記録媒体，垂直磁気記
録媒体を保持するための保持具，垂直磁気記録媒体に情
報を記録，再生するための磁気ヘッド，磁気ヘッドと垂
直磁気記録媒体の相対位置を移動させるための移動手
段、及びこれら各部を制御するための制御手段から構成
される。The magnetic recording apparatus of the present invention has the perpendicular magnetic recording medium having the above-described first and second configurations, a holder for holding the perpendicular magnetic recording medium, and information recording / reproducing on / from the perpendicular magnetic recording medium. A magnetic head for moving the magnetic head, a moving means for moving the relative position of the magnetic head and the perpendicular magnetic recording medium, and a control means for controlling each of these parts.
【００１５】[0015]
【作用】上記の構成に用いるＣｏＲｕ合金は、常温で全
組成範囲にわたって固溶体をつくることが知られてい
る。結晶構造はＣｏ及びＲｕと同じく六方最密充填構造
である。ガラス基板やＮｉＰをコーティングしたＡｌ合
金基板のような非晶質の表面を持つ基板上にこの合金の
薄膜を形成すると、（０００１）面が基板に平行にな
り、ｃ軸が垂直配向しやすい。このため、垂直磁気記録
媒体の記録膜として用いるＣｏ合金磁性膜のｃ軸垂直配
向性を向上させるための下地膜として用いることができ
る。Ｒｕの濃度が４０ａｔ％以上の組成域では、キュリ
ー温度が０℃以下になるため、この合金は強磁性を示さ
なくなる。非磁性の下地膜として用いる場合、Ｒｕの濃
度が４０ａｔ％Ｒｕ以上の範囲で用いるのが適切であ
る。It is known that the CoRu alloy used in the above structure forms a solid solution over the entire composition range at room temperature. The crystal structure is a hexagonal close-packed structure like Co and Ru. When a thin film of this alloy is formed on a substrate having an amorphous surface such as a glass substrate or a NiP-coated Al alloy substrate, the (0001) plane becomes parallel to the substrate, and the c-axis is easily oriented vertically. Therefore, it can be used as a base film for improving the c-axis vertical orientation of the Co alloy magnetic film used as the recording film of the perpendicular magnetic recording medium. In the composition range where the Ru concentration is 40 at% or higher, the Curie temperature is 0 ° C. or lower, so that this alloy does not exhibit ferromagnetism. When used as a non-magnetic underlayer, it is suitable to use Ru in a concentration of 40 at% Ru or more.
【００１６】ＣｏＲｕ合金の格子定数は、合金の組成に
比例して連続的に変化する。Ｃｏ及びＲｕのａ軸の格子
定数はそれぞれ０.２５１ｎｍ，０.２７０ｎｍである。
Ｃｏ−４０ａｔ％Ｒｕの格子定数は０.２５９ ｎｍであ
る。したがって、Ｃｏ−４０ａｔ％Ｒｕの合金を下地膜
に用いれば、Ｃｏ合金磁性膜（ａ軸の格子定数が約０.
２５ｎｍ)との格子定数の差は、ＣｏＲｕ合金を基準に
して−３％と小さくなる。したがって、この合金を下地
膜として用いると、Ｃｏ合金の初期成長時の配向の乱れ
を防止し、ｃ軸垂直配向性の高い垂直磁化膜を作製する
ことができる。The lattice constant of CoRu alloy continuously changes in proportion to the composition of the alloy. The a-axis lattice constants of Co and Ru are 0.251 nm and 0.270 nm, respectively.
The lattice constant of Co-40 at% Ru is 0.259 nm. Therefore, if an alloy of Co-40at% Ru is used for the underlayer film, the Co alloy magnetic film (the lattice constant of the a-axis is about 0.
25 nm) and the difference in lattice constant are as small as -3% based on the CoRu alloy. Therefore, when this alloy is used as the base film, the disorder of the orientation of the Co alloy during the initial growth can be prevented, and the perpendicular magnetization film having a high c-axis perpendicular orientation can be manufactured.
【００１７】Ｒｕ及びＴｉは、ｃ軸垂直配向しやすい
が、Ｃｏ合金磁性膜とのａ軸の格子定数の差は、Ｒｕを
下地膜に用いる場合は、−７％、Ｔｉを用いる場合は、
−１５％となり、ＣｏＲｕ合金の場合に比べていずれも
大きい。そこでＴｉあるいはＲｕの下地膜を形成した
後、その表面にＣｏＲｕ合金下地膜を形成することによ
り、格子定数差を緩和し、Ｃｏ合金の格子定数に近い格
子定数を持つ下地膜を作製することができる。Ru and Ti are likely to be vertically oriented on the c-axis, but the difference in the lattice constant of the a-axis from the Co alloy magnetic film is -7% when Ru is used as the underlayer, and when Ti is used,
-15%, which is larger than that of CoRu alloy. Therefore, by forming a Ti or Ru underlayer and then forming a CoRu alloy underlayer on the surface thereof, it is possible to alleviate the difference in lattice constant and produce an underlayer having a lattice constant close to that of Co alloy. it can.
【００１８】さらに、ＣｏＲｕ合金下地膜を、Ｒｕ濃度
の異なる二層の膜からなる構成とし、ＴｉあるいはＲｕ
の下地膜上にＲｕ濃度の高い層を形成し、その表面にＲ
ｕ濃度の低い層を形成することで、効果的に格子定数差
を緩和することができる。また、ＣｏＲｕ合金下地膜の
Ｒｕ濃度を、基板に近い側から垂直磁化膜側に向かっ
て、連続的に低下させることによっても、格子定数差を
緩和することができる。Further, the CoRu alloy base film is constituted by two layers of films having different Ru concentrations, and Ti or Ru is used.
Layer with a high Ru concentration is formed on the underlayer film of
By forming the layer having a low u concentration, the difference in lattice constant can be effectively mitigated. The lattice constant difference can also be relaxed by continuously decreasing the Ru concentration of the CoRu alloy underlayer film from the side closer to the substrate toward the side of the perpendicular magnetization film.
【００１９】このように、Ｃｏ合金磁性膜のａ軸の格子
定数に近い格子定数を持つＣｏＲｕ合金を、下地膜に用
いることにより、Ｃｏ合金磁性膜のｃ軸垂直配向性を高
め、従来よりも高密度記録に適した垂直磁気記録媒体を
提供できる。As described above, by using the CoRu alloy having a lattice constant close to that of the a-axis of the Co alloy magnetic film for the underlayer, the c-axis vertical orientation of the Co alloy magnetic film is enhanced, and the CoRu alloy magnetic film has a higher orientation than the conventional one. A perpendicular magnetic recording medium suitable for high density recording can be provided.
【００２０】[0020]
＜実施例１＞直径２.５ インチのガラス基板を用い、図
３に示すような断面構造を持つ磁気記録媒体を、ＤＣマ
グネトロンスパッタリング法によって作製した。基板３
１の両面に、ＣｏＲｕ合金下地膜３２，３２′，Ｃｏ合
金磁性膜３３，３３′，カーボン保護膜３４，３４′を
この順序で形成する。Example 1 A magnetic recording medium having a cross-sectional structure as shown in FIG. 3 was produced by a DC magnetron sputtering method using a glass substrate having a diameter of 2.5 inches. Board 3
CoRu alloy base films 32 and 32 ', Co alloy magnetic films 33 and 33', and carbon protective films 34 and 34 'are formed in this order on both surfaces of No. 1 in this order.
【００２１】成膜には、アルゴンガスを用い、ガスの圧
力０.７ Ｐａ，基板温度２６０℃，成膜速度毎分５０ｎ
ｍの条件で形成した。下地膜の形成に用いるターゲット
の組成はＣｏ−４０ａｔ％Ｒｕ，磁性膜の形成に用いる
ターゲットの組成はＣｏ−１５ａｔ％Ｃｒ−５ａｔ％Ｔ
ａとした。この組成のＣｏ合金磁性膜のａ軸の長さは
０.２５１ ｎｍであった。各膜の膜厚は、ＣｏＲｕ合金
下地膜が５０ｎｍ，Ｃｏ合金磁性膜が１００ｎｍ，カー
ボン保護膜が１０ｎｍとした。上記の膜形成はすべて同
一の真空槽内で真空を破ることなく連続して行った。Argon gas was used for film formation, the gas pressure was 0.7 Pa, the substrate temperature was 260 ° C., and the film formation rate was 50 n / min.
It was formed under the condition of m. The composition of the target used for forming the underlayer film is Co-40 at% Ru, and the composition of the target used for forming the magnetic film is Co-15 at% Cr-5 at% T.
a. The a-axis length of the Co alloy magnetic film having this composition was 0.251 nm. The film thickness of each film was 50 nm for the CoRu alloy base film, 100 nm for the Co alloy magnetic film, and 10 nm for the carbon protective film. The above film formation was continuously performed in the same vacuum chamber without breaking the vacuum.
【００２２】作製した試料の結晶配向をＸ線回折によっ
て、磁気特性を試料振動型磁力計（ＶＳＭ）を用いてそ
れぞれ測定した。Ｘ線回折では、ＣｏＲｕ合金下地膜及
びＣｏ合金磁性膜の０００２回折ピークが観測され、こ
の膜が［０００１］配向していることがわかった。Ｃｏ
合金磁性膜のＸ線０００２回折ピークのロッキング曲線
を測定したところ、本実施例の磁気記録媒体は、下地膜
を用いずに全く同様の条件で作製した磁気記録媒体と比
較して、ロッキング曲線の半値幅が減少しており、Ｃｏ
合金磁性膜の［０００１］配向が改善されていた。膜面
垂直方向の保磁力は３８％（４２０Ｏｅ）向上した。The crystal orientation of the prepared sample was measured by X-ray diffraction, and the magnetic characteristics were measured by using a sample vibrating magnetometer (VSM). In X-ray diffraction, a 0002 diffraction peak of the CoRu alloy underlayer film and the Co alloy magnetic film was observed, and it was found that this film had a [0001] orientation. Co
When the rocking curve of the X-ray 0002 diffraction peak of the alloy magnetic film was measured, the rocking curve of the magnetic recording medium of this example was higher than that of the magnetic recording medium manufactured under the same conditions without using the underlayer film. The full width at half maximum has decreased and Co
The [0001] orientation of the alloy magnetic film was improved. The coercive force in the direction perpendicular to the film surface was improved by 38% (420 Oe).
【００２３】さらに下地膜にＣｏ−５０ａｔ％Ｒｕ合
金，Ｃｏ−７５ａｔ％Ｒｕ合金を用いた場合にも、改善
効果が認められた。これらの結果を表１に示す。Further, when the Co-50 at% Ru alloy and the Co-75 at% Ru alloy were used for the underlayer film, the improvement effect was recognized. Table 1 shows the results.
【００２４】[0024]
【表１】 [Table 1]
【００２５】〈実施例２〉直径１.８ インチのＮｉＰを
コーティングしたＡｌ合金基板を用い、図４に示すよう
な断面構造を持つ磁気記録媒体を、ＤＣマグネトロンス
パッタリング法によって作製した。基板４１の両面に、
Ｒｕからなる第一の下地膜４２，４２′，ＣｏＲｕ合金
からなる第二の下地膜４３，４３′，Ｃｏ合金磁性膜４
４，４４′，カーボン保護膜４５，４５′をこの順序で
形成する。Example 2 A magnetic recording medium having a cross-sectional structure as shown in FIG. 4 was produced by a DC magnetron sputtering method using an Al alloy substrate coated with NiP having a diameter of 1.8 inches. On both sides of the substrate 41,
First underlayer films 42, 42 'made of Ru, second underlayer films 43, 43' made of CoRu alloy, Co alloy magnetic film 4
4, 44 'and carbon protective films 45, 45' are formed in this order.
【００２６】成膜には、アルゴンガスを用い、ガスの圧
力０.７ Ｐａ，基板温度２６０℃，成膜速度毎分５０ｎ
ｍの条件で形成した。ＣｏＲｕ合金下地膜の形成に用い
るターゲットの組成はＣｏ−４０ａｔ％Ｒｕ，磁性膜の
形成に用いるターゲットの組成はＣｏ−１２ａｔ％Ｃｒ
−１０ａｔ％Ｐｔとした。この組成のＣｏ合金磁性膜の
ａ軸の長さは０.２５５ ｎｍであった。各膜の膜厚は、
Ｒｕ下地膜が３０ｎｍ，ＣｏＲｕ合金下地膜が５０ｎ
ｍ，Ｃｏ合金磁性膜が１００ｎｍ，カーボン保護膜が１
０ｎｍとした。上記の膜形成はすべて同一の真空槽内で
真空を破ることなく連続して行った。Argon gas was used for film formation, the gas pressure was 0.7 Pa, the substrate temperature was 260 ° C., and the film formation rate was 50 n / min.
It was formed under the condition of m. The composition of the target used to form the CoRu alloy underlayer film is Co-40 at% Ru, and the composition of the target used to form the magnetic film is Co-12 at% Cr.
It was set to -10 at% Pt. The a-axis length of the Co alloy magnetic film having this composition was 0.255 nm. The thickness of each film is
Ru base film 30 nm, CoRu alloy base film 50 n
m, Co alloy magnetic film 100 nm, carbon protective film 1
It was set to 0 nm. The above film formation was continuously performed in the same vacuum chamber without breaking the vacuum.
【００２７】作製した試料の結晶配向をＸ線回折によっ
て、磁気特性を試料振動型磁力計（ＶＳＭ）を用いてそ
れぞれ測定した。Ｘ線回折では、Ｒｕ下地膜，ＣｏＲｕ
合金下地膜及びＣｏ合金磁性膜の０００２回折ピークが
観測され、この膜が［０００１］配向していることがわ
かった。Ｃｏ合金磁性膜のＸ線０００２回折ピークのロ
ッキング曲線を測定したところ、本実施例の磁気記録媒
体は、ＣoＲu合金下地膜を用いずに全く同様の条件で作
製した磁気記録媒体と比較して、ロッキング曲線の半値
幅が減少しており、Ｃｏ合金磁性膜の［０００１］配向
が改善されていた。膜面垂直方向の保磁力は１３％（１
９０Ｏｅ）向上した。The crystal orientation of the prepared sample was measured by X-ray diffraction, and the magnetic characteristics were measured by using a sample vibrating magnetometer (VSM). In X-ray diffraction, Ru underlayer, CoRu
0002 diffraction peaks of the alloy underlayer film and the Co alloy magnetic film were observed, and it was found that this film had a [0001] orientation. When the rocking curve of the X-ray 0002 diffraction peak of the Co alloy magnetic film was measured, the magnetic recording medium of this example was compared with a magnetic recording medium produced under exactly the same conditions without using the CoRu alloy underlayer film. The half-width of the rocking curve was reduced, and the [0001] orientation of the Co alloy magnetic film was improved. The coercive force in the direction perpendicular to the film surface is 13% (1
90 Oe) improved.
【００２８】さらにＲｕ下地膜に代えて、Ｔｉ下地膜を
用いた場合にも、改善効果が認められた。これらの結果
を表２に示す。Further, when the Ti underlayer film was used instead of the Ru underlayer film, the improvement effect was recognized. Table 2 shows the results.
【００２９】[0029]
【表２】 [Table 2]
【００３０】このような垂直磁気記録媒体を用いて、図
５に模式的に示すような垂直磁気記録方式による磁気記
録装置を作製した。垂直磁気記録媒体５１は、モータに
より回転する保持具により保持され、それぞれの各磁性
膜に対応して情報の書き込み，読み出しのための磁気ヘ
ッド５２が配置されている。この磁気ヘッド５２の磁気
記録媒体５１に対する位置をアクチュエータ５３とボイ
スコイルモータ５４により移動させる。さらにこれらを
制御するために記録再生回路５５，位置決め回路５６，
インターフェース制御回路５７が設けられている。Ｃｏ
Ｒｕ下地膜を用いた垂直磁気記録媒体で、高密度記録が
可能であることを確かめた。Using such a perpendicular magnetic recording medium, a magnetic recording apparatus according to the perpendicular magnetic recording system as schematically shown in FIG. 5 was manufactured. The perpendicular magnetic recording medium 51 is held by a holder rotated by a motor, and a magnetic head 52 for writing and reading information is arranged corresponding to each magnetic film. The position of the magnetic head 52 with respect to the magnetic recording medium 51 is moved by the actuator 53 and the voice coil motor 54. Further, in order to control these, a recording / reproducing circuit 55, a positioning circuit 56,
An interface control circuit 57 is provided. Co
It was confirmed that high density recording is possible with a perpendicular magnetic recording medium using a Ru underlayer.
【００３１】〈実施例３〉直径１.８ インチのガラス基
板を用い、図４に示すような断面構造を持つ磁気記録媒
体を、イオンビームスパッタリング法によって作製し
た。基板４１の両面に、Ｒｕからなる第一の下地膜４
２，４２′，ＣｏＲｕ合金からなる第二の下地膜４３，
４３′，Ｃｏ合金磁性膜４４，４４′，カーボン保護膜
４５，４５′をこの順序で形成する。Example 3 Using a glass substrate having a diameter of 1.8 inches, a magnetic recording medium having a cross sectional structure as shown in FIG. 4 was produced by the ion beam sputtering method. The first base film 4 made of Ru is formed on both surfaces of the substrate 41.
2, 42 ', a second base film 43 made of a CoRu alloy,
43 ', Co alloy magnetic films 44 and 44', and carbon protective films 45 and 45 'are formed in this order.
【００３２】成膜には、アルゴンガスを用い、基板温度
２６０℃，成膜速度毎分５０ｎｍの条件で形成した。Ｃ
ｏＲｕ合金下地膜の形成には、二つのイオン銃を用い、
ＣｏターゲットとＲｕターゲットを独立にスパッタリン
グして同時に成膜した。Ｒｕの成膜速度を制御すること
によって、膜中のＲｕの濃度を、膜厚方向に連続的に変
化させた。磁性膜の形成に用いるターゲットの組成はＣ
ｏ−１２ａｔ％Ｃｒ−１０ａｔ％Ｐｔとした。この組成
のＣo合金磁性膜のａ軸の長さは０.２５５ｎｍであっ
た。各膜の膜厚は、Ｒｕ下地膜が３０ｎｍ，ＣｏＲｕ合
金下地膜が５０ｎｍ，Ｃｏ合金磁性膜が１００ｎｍ，カ
ーボン保護膜が１０ｎｍとした。上記の膜形成はすべて
同一の真空槽内で真空を破ることなく連続して行った。Argon gas was used for the film formation, and the substrate temperature was 260 ° C. and the film formation rate was 50 nm / min. C
Two ion guns were used to form the oRu alloy base film,
A Co target and a Ru target were independently sputtered and deposited simultaneously. By controlling the Ru film formation rate, the Ru concentration in the film was continuously changed in the film thickness direction. The composition of the target used for forming the magnetic film is C
It was o-12 at% Cr-10 at% Pt. The length of the a-axis of the Co alloy magnetic film having this composition was 0.255 nm. The film thickness of each film was 30 nm for the Ru underlayer film, 50 nm for the CoRu alloy underlayer film, 100 nm for the Co alloy magnetic film, and 10 nm for the carbon protective film. The above film formation was continuously performed in the same vacuum chamber without breaking the vacuum.
【００３３】作製した試料の結晶配向をＸ線回折で、膜
厚方向の組成の変化をオージェ電子分光法により、磁気
特性を試料振動型磁力計（ＶＳＭ）を用いてそれぞれ測
定した。Ｘ線回折では、Ｒｕ下地膜，ＣｏＲｕ合金下地
膜及びＣｏ合金磁性膜の0002回折ピークが観測され、こ
の膜が［０００１］配向していることがわかった。Ｃｏ
合金磁性膜のＸ線０００２回折ピークのロッキング曲線
を測定したところ、本実施例の磁気記録媒体は、ＣｏＲ
ｕ合金下地膜を用いずに全く同様の条件で作製した磁気
記録媒体と比較して、ロッキング曲線の半値幅が３５％
減少しており、Ｃｏ合金磁性膜の［０００１］配向が改
善されていた。ＣｏＲｕ合金下地膜の膜厚方向の組成分
布は、膜表面に向かってＲｕ濃度がなだらかに減少して
おり、Ｒｕ下地膜との界面付近でＣｏ−７２ａｔ％Ｒ
ｕ，Ｃｏ合金磁性膜との界面付近でＣｏ−４６ａｔ％Ｒ
ｕであった。The crystal orientation of the prepared sample was measured by X-ray diffraction, the change in composition in the film thickness direction was measured by Auger electron spectroscopy, and the magnetic characteristics were measured by a sample vibrating magnetometer (VSM). In X-ray diffraction, 0002 diffraction peaks of the Ru underlayer film, the CoRu alloy underlayer film, and the Co alloy magnetic film were observed, and it was found that this film had a [0001] orientation. Co
The rocking curve of the X-ray 0002 diffraction peak of the alloy magnetic film was measured, and it was found that the magnetic recording medium of this example had CoR
The full width at half maximum of the rocking curve is 35% compared to the magnetic recording medium produced under exactly the same conditions without using the u alloy underlayer.
And the [0001] orientation of the Co alloy magnetic film was improved. The compositional distribution in the film thickness direction of the CoRu alloy underlayer film has a gradually decreasing Ru concentration toward the film surface, and Co-72at% R near the interface with the Ru underlayer film.
Co-46 at% R near the interface with the u and Co alloy magnetic film
It was u.
【００３４】この組成のＣｏＲｕ合金のａ軸の長さを見
積もると、Ｒｕ下地膜との界面付近で０.２６５ｎｍ，
Ｃｏ合金磁性膜との界面付近で０.２６０ｎｍである。
この値から見積もった、格子のミスフィット量は、Ｒｕ
下地膜とＣｏＲｕ合金下地膜の界面で−４.０％，Ｃｏ
Ｒｕ合金下地膜とＣｏ合金磁性膜の界面で−１.８％で
ある。膜面垂直方向の保磁力も２１％（３１０Ｏｅ）向
上した。The length of the a-axis of the CoRu alloy of this composition was estimated to be 0.265 nm near the interface with the Ru underlayer.
The thickness is 0.260 nm near the interface with the Co alloy magnetic film.
The amount of lattice misfit estimated from this value is Ru
At the interface between the base film and the CoRu alloy base film, -4.0%, Co
It is -1.8% at the interface between the Ru alloy base film and the Co alloy magnetic film. The coercive force in the direction perpendicular to the film surface was also improved by 21% (310 Oe).
【００３５】〈実施例４〉直径１.８ インチのガラス基
板を用い、図６に示すような断面構造を持つ磁気記録媒
体を、ＤＣマグネトロンスパッタリング法によって作製
した。基板６１の両面に、Ｔｉ下地膜６２，６２′,Ｃ
ｏ−７０ａｔ％Ｒｕ合金下地膜６３,６３′，Ｃｏ−４
０ａｔ％Ｒｕ合金下地膜６４，６４′，Ｃｏ合金磁性膜
６５，６５′，カーボン保護膜６６，６６′をこの順序
で形成する。成膜に先立ち、基板の表面をアルゴンイオ
ンによってスパッタリングし、平均深さ約２ｎｍの微細
な起伏を形成した。成膜には、アルゴンガスを用い、基
板温度２５０℃，成膜速度毎分５０ｎｍの条件で形成し
た。Example 4 Using a glass substrate having a diameter of 1.8 inches, a magnetic recording medium having a cross sectional structure as shown in FIG. 6 was produced by the DC magnetron sputtering method. On both surfaces of the substrate 61, Ti base films 62, 62 ', C
o-70 at% Ru alloy base film 63, 63 ', Co-4
The 0 at% Ru alloy base films 64 and 64 ', the Co alloy magnetic films 65 and 65', and the carbon protective films 66 and 66 'are formed in this order. Prior to film formation, the surface of the substrate was sputtered with argon ions to form fine undulations having an average depth of about 2 nm. Argon gas was used for the film formation, and the substrate temperature was 250 ° C. and the film formation rate was 50 nm / min.
【００３６】磁性膜の形成に用いるターゲットの組成は
Ｃo−１５ａｔ％Ｃｒ−５ａｔ％Ｔaとした。この組成の
Ｃｏ合金磁性膜のａ軸の長さは０.２５１ ｎｍであっ
た。各膜の膜厚は、Ｔｉ下地膜が３０ｎｍ，Ｃｏ−７０
ａｔ％Ｒｕ合金下地膜が２５ｎｍ，Ｃｏ−４０ａｔ％Ｒ
ｕ合金下地膜が２５ｎｍ，Ｃｏ合金磁性膜が１００ｎ
ｍ，カーボン保護膜が１０ｎｍとした。上記の膜形成は
すべて同一の真空槽内で真空を破ることなく連続して行
った。The composition of the target used for forming the magnetic film was Co-15 at% Cr-5 at% Ta. The a-axis length of the Co alloy magnetic film having this composition was 0.251 nm. Regarding the film thickness of each film, the Ti underlayer film is 30 nm, Co-70
at% Ru alloy base film is 25 nm, Co-40 at% R
u alloy underlayer film is 25 nm, Co alloy magnetic film is 100 n
m, the carbon protective film was 10 nm. The above film formation was continuously performed in the same vacuum chamber without breaking the vacuum.
【００３７】作製した試料の結晶配向をＸ線回折で、磁
気特性を試料振動型磁力計(ＶＳＭ)を用いてそれぞれ測
定した。Ｘ線回折では、Ｔｉ下地膜，ＣｏＲｕ合金下地
膜及びＣｏ合金磁性膜の０００２回折ピークが観測さ
れ、この膜が［０００１］配向していることがわかっ
た。The crystal orientation of the produced sample was measured by X-ray diffraction, and the magnetic characteristics were measured by using a sample vibrating magnetometer (VSM). In X-ray diffraction, 0002 diffraction peaks of the Ti underlayer film, the CoRu alloy underlayer film, and the Co alloy magnetic film were observed, and it was found that this film had a [0001] orientation.
【００３８】Ｃｏ合金磁性膜のＸ線０００２回折ピーク
のロッキング曲線を測定したところ、本実施例の磁気記
録媒体は、ＣｏＲｕ合金下地膜を用いずに全く同様の条
件で作製した磁気記録媒体と比較して、ロッキング曲線
の半値幅が２７％減少しており、Ｃｏ合金磁性膜の［０
００１］配向が改善されていた。この場合の格子のミス
フィット量は、Ｔｉ下地膜とＣｏ−７０ａｔ％Ｒｕ合金
下地膜の界面で−１０％，Ｃｏ−７０ａｔ％Ｒｕ合金下
地膜とＣｏ−４０ａｔ％Ｒｕ合金下地膜の界面で−２.
２ ％，Ｃｏ−４０ａｔ％Ｒｕ合金下地膜とＣｏ合金磁
性膜の界面で−２.９ ％である。膜面垂直方向の保磁力
も、ＣｏＲｕ合金下地膜を用いずに全く同様の条件で作
製した磁気記録媒体と比較して８％（１３０Ｏｅ）向上
した。The rocking curve of the X-ray 0002 diffraction peak of the Co alloy magnetic film was measured, and the magnetic recording medium of this example was compared with the magnetic recording medium prepared under exactly the same conditions without using the CoRu alloy underlayer. As a result, the full width at half maximum of the rocking curve is reduced by 27%, and the [0
001] orientation was improved. In this case, the amount of lattice misfit is -10% at the interface between the Ti underlayer and the Co-70at% Ru alloy underlayer, and at the interface between the Co-70at% Ru alloy underlayer and the Co-40at% Ru alloy underlayer- 2.
2%, Co-40 at% Ru-2.9% at the interface between the Ru alloy underlayer and the Co alloy magnetic film. The coercive force in the direction perpendicular to the film surface was also improved by 8% (130 Oe) as compared with the magnetic recording medium manufactured under exactly the same conditions without using the CoRu alloy base film.
【００３９】この垂直磁気記録媒体を用いて、図５に模
式的に示すような垂直磁気記録方式による磁気記録装置
を作製した。基板表面の微細な起伏の効果で、磁気ヘッ
ドが媒体表面に固着することなく、安定した記録再生が
行えた。Using this perpendicular magnetic recording medium, a magnetic recording device of the perpendicular magnetic recording system as schematically shown in FIG. 5 was produced. Due to the effect of fine undulations on the substrate surface, stable recording and reproduction could be performed without the magnetic head sticking to the medium surface.
【００４０】[0040]
【発明の効果】本発明のように、ＣｏＲｕ合金を下地膜
に用いることにより、Ｃｏ合金磁性膜のｃ軸垂直配向性
を高め、従来よりも高密度記録に適した高性能の垂直磁
気記録媒体を提供することができる。As in the present invention, by using a CoRu alloy for the underlayer film, the c-axis vertical orientation of the Co alloy magnetic film is enhanced, and a high-performance perpendicular magnetic recording medium suitable for high-density recording as compared with the prior art. Can be provided.
【図１】本発明の第一の実施例の垂直磁気記録媒体の断
面構造の説明図。FIG. 1 is an explanatory diagram of a sectional structure of a perpendicular magnetic recording medium according to a first embodiment of the present invention.
【図２】本発明の第二の実施例の垂直磁気記録媒体の断
面構造の説明図。FIG. 2 is an explanatory view of a sectional structure of a perpendicular magnetic recording medium of a second embodiment of the present invention.
【図３】本発明の第一の実施例の垂直磁気記録媒体の断
面構造の説明図。FIG. 3 is an explanatory diagram of a cross-sectional structure of the perpendicular magnetic recording medium of the first embodiment of the present invention.
【図４】本発明の第二の実施例の垂直磁気記録媒体の断
面構造の説明図。FIG. 4 is an explanatory view of a sectional structure of a perpendicular magnetic recording medium according to a second embodiment of the invention.
【図５】本発明の磁気記録装置のブロック図。FIG. 5 is a block diagram of a magnetic recording device of the present invention.
【図６】本発明の第三の実施例の垂直磁気記録媒体の断
面構造の説明図。FIG. 6 is an explanatory diagram of a sectional structure of a perpendicular magnetic recording medium according to a third embodiment of the invention.
１１…非磁性基板、１２…ＣｏＲｕ合金下地膜、１３…
Ｃｏ合金磁性膜、１４…保護膜。11 ... Non-magnetic substrate, 12 ... CoRu alloy base film, 13 ...
Co alloy magnetic film, 14 ... Protective film.
───────────────────────────────────────────────────── フロントページの続き (72)発明者 高山 孝信 東京都国分寺市東恋ケ窪１丁目280番地 株式会社日立製作所中央研究所内 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Takanobu Takayama 1-280 Higashi Koikekubo, Kokubunji, Tokyo Inside the Central Research Laboratory, Hitachi, Ltd.
Claims (8)
れた下地膜と，前記下地膜上に形成されたＣｏを主成分
とする合金からなる垂直磁化膜と，前記垂直磁化膜上に
形成された保護膜とからなる垂直磁気記録媒体におい
て、前記下地膜がＣｏとＲｕの合金からなることを特徴
とする垂直磁気記録媒体。1. A non-magnetic substrate, a base film formed on the non-magnetic substrate, a perpendicular magnetization film formed on the base film and made of an alloy containing Co as a main component, and a perpendicular magnetization film on the perpendicular magnetization film. A perpendicular magnetic recording medium comprising a protective film formed on the underlayer, wherein the underlayer film is made of an alloy of Co and Ru.
れた第一の下地膜と，前記第一の下地膜上に形成された
第二の下地膜と，前記第二の下地膜上に形成されたＣｏ
を主成分とする合金の垂直磁化膜と，前記垂直磁化膜上
に形成された保護膜とからなる垂直磁気記録媒体におい
て、前記第一の下地膜がＴｉまたはＲｕのいずれかから
なり、前記第二の下地膜がＣｏとＲｕの合金からなるこ
とを特徴とする垂直磁気記録媒体。2. A non-magnetic substrate, a first base film formed on the non-magnetic substrate, a second base film formed on the first base film, and the second base film. Co formed on top
In a perpendicular magnetic recording medium comprising a vertically magnetized film of an alloy containing as a main component and a protective film formed on the vertically magnetized film, the first underlayer is made of either Ti or Ru. A perpendicular magnetic recording medium, wherein the second underlayer film is made of an alloy of Co and Ru.
なる前記下地膜が、Ｒｕの濃度の異なる二層の膜からな
り、前記垂直磁化膜の直下に位置する層のＲｕ濃度が、
その直下に位置する層のＲｕ濃度よりも低い垂直磁気記
録媒体。3. The underlayer film made of an alloy of Co and Ru is formed of two layers having different Ru concentrations, and the Ru concentration of a layer located immediately below the perpendicularly magnetized film is:
A perpendicular magnetic recording medium having a Ru concentration lower than that of a layer located thereunder.
る、前記ＣｏとＲｕの合金からなる下地膜において、Ｒ
ｕの濃度が、前記非磁性基板に近い側から前記垂直磁化
膜側に向かって、連続的に低下している垂直磁気記録媒
体。4. The perpendicular film of the perpendicular magnetic recording medium according to claim 2, wherein R is a base film made of an alloy of Co and Ru.
A perpendicular magnetic recording medium in which the concentration of u continuously decreases from the side closer to the non-magnetic substrate toward the side of the perpendicular magnetization film.
気記録媒体における、前記ＣｏとＲｕの合金からなる下
地膜において、Ｒｕの濃度が、４０ａｔ％Ｒｕ以上であ
る垂直磁気記録媒体。5. The perpendicular magnetic recording medium according to any one of claims 1 to 4, wherein in the underlayer film made of an alloy of Co and Ru, the Ru concentration is 40 at% Ru or more.
各下地膜の優先配向方位と、前記垂直磁化膜の優先配向
方位が、ともに［０００１］である垂直磁気記録媒体。6. A perpendicular magnetic recording medium according to claim 1, 2, 3 or 4, wherein the preferred orientation azimuth of each underlayer and the preferred orientation azimuth of the perpendicular magnetization film are both [0001].
非磁性基板の表面に微細な起伏を設けた垂直磁気記録媒
体。7. The perpendicular magnetic recording medium according to claim 1, 2, 3 or 4, wherein fine undulations are provided on the surface of the non-magnetic substrate.
記載の垂直磁気記録媒体，前記垂直磁気記録媒体を保持
するための保持具，前記垂直磁気記録媒体に情報を記
録，再生するための磁気ヘッド，前記磁気ヘッドと前記
垂直磁気記録媒体の相対位置を移動させるための移動手
段、及びこれら各部を制御するための制御手段を有する
磁気記録装置。8. A perpendicular magnetic recording medium according to claim 1, 2, 3, 4, 5, 6 or 7, a holder for holding the perpendicular magnetic recording medium, and information recorded on the perpendicular magnetic recording medium. A magnetic recording device having a magnetic head for reproducing, a moving means for moving the relative position of the magnetic head and the perpendicular magnetic recording medium, and a control means for controlling each of these parts.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP31795194A JP3345199B2 (en) | 1994-12-21 | 1994-12-21 | Perpendicular magnetic recording medium and magnetic recording device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP31795194A JP3345199B2 (en) | 1994-12-21 | 1994-12-21 | Perpendicular magnetic recording medium and magnetic recording device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH08180360A true JPH08180360A (en) | 1996-07-12 |
| JP3345199B2 JP3345199B2 (en) | 2002-11-18 |
Family
ID=18093839
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP31795194A Expired - Fee Related JP3345199B2 (en) | 1994-12-21 | 1994-12-21 | Perpendicular magnetic recording medium and magnetic recording device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3345199B2 (en) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7083870B2 (en) | 2002-07-12 | 2006-08-01 | Showa Denko K. K. | Magnetic recording medium, method of manufacturing the same, and magnetic recording and reproduction apparatus |
| US7141315B2 (en) | 2002-07-31 | 2006-11-28 | Showa Denko K.K. | Magnetic recording medium, method of manufacturing the same, and magnetic recording and reproduction apparatus |
| JP2009187596A (en) * | 2008-02-01 | 2009-08-20 | Fujitsu Ltd | Vertical magnetic recording medium and magnetic storage unit |
| JP2011192326A (en) * | 2010-03-12 | 2011-09-29 | Showa Denko Kk | Magnetic recording medium and magnetic recording and reproducing device |
| WO2012081668A1 (en) * | 2010-12-17 | 2012-06-21 | Jx日鉱日石金属株式会社 | Ferromagnetic material sputtering target |
| WO2012086575A1 (en) * | 2010-12-22 | 2012-06-28 | Jx日鉱日石金属株式会社 | Ferromagnetic sputtering target |
-
1994
- 1994-12-21 JP JP31795194A patent/JP3345199B2/en not_active Expired - Fee Related
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7083870B2 (en) | 2002-07-12 | 2006-08-01 | Showa Denko K. K. | Magnetic recording medium, method of manufacturing the same, and magnetic recording and reproduction apparatus |
| US7141315B2 (en) | 2002-07-31 | 2006-11-28 | Showa Denko K.K. | Magnetic recording medium, method of manufacturing the same, and magnetic recording and reproduction apparatus |
| JP2009187596A (en) * | 2008-02-01 | 2009-08-20 | Fujitsu Ltd | Vertical magnetic recording medium and magnetic storage unit |
| JP2011192326A (en) * | 2010-03-12 | 2011-09-29 | Showa Denko Kk | Magnetic recording medium and magnetic recording and reproducing device |
| WO2012081668A1 (en) * | 2010-12-17 | 2012-06-21 | Jx日鉱日石金属株式会社 | Ferromagnetic material sputtering target |
| WO2012086575A1 (en) * | 2010-12-22 | 2012-06-28 | Jx日鉱日石金属株式会社 | Ferromagnetic sputtering target |
| CN103180481A (en) * | 2010-12-22 | 2013-06-26 | 吉坤日矿日石金属株式会社 | Ferromagnetic sputtering target |
Also Published As
| Publication number | Publication date |
|---|---|
| JP3345199B2 (en) | 2002-11-18 |
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