JPH11296833A - Perpendicular magnetic recording medium and magnetic memory device - Google Patents
Perpendicular magnetic recording medium and magnetic memory deviceInfo
- Publication number
- JPH11296833A JPH11296833A JP9333498A JP9333498A JPH11296833A JP H11296833 A JPH11296833 A JP H11296833A JP 9333498 A JP9333498 A JP 9333498A JP 9333498 A JP9333498 A JP 9333498A JP H11296833 A JPH11296833 A JP H11296833A
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- Japan
- Prior art keywords
- magnetic
- film
- recording medium
- magnetic recording
- perpendicular magnetic
- Prior art date
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- Recording Or Reproducing By Magnetic Means (AREA)
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、高密度磁気記録に
適する垂直磁化膜を有する垂直磁気記録媒体及びこれを
用いた磁気記憶装置に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a perpendicular magnetic recording medium having a perpendicular magnetic film suitable for high-density magnetic recording and a magnetic storage device using the same.
【０００２】[0002]
【従来の技術】現在実用化されている磁気ディスク装置
は、面内磁気記録方式を採用している。面内磁気記録方
式においては、ディスク基板面と平行な方向に磁化し易
い面内磁気記録媒体に基板と平行な面内磁区を高密度に
形成することが技術課題となっている。この面内磁気記
録媒体の記録密度を伸ばす方式として、面内方向に磁化
容易軸を持つ記録媒体表面に、極薄の軟磁性膜を形成し
たキーパードメディアを用いる方法が提案されている。
この技術は例えば、41st Annual Conference onMagneti
sm & Magnetic Materials (November 12-15, 1996)で発
行されたアブストラクト集の１１６ページ（論文番号Ｄ
Ｑ−１３）及び１３３ページ（論文番号ＥＢ−１２）な
どに掲載されている。このような媒体構造を採用するこ
とにより、自己記録再生方式の薄膜ヘッドを用いて、磁
気記録の面記録密度を１Ｇｂ／ｉｎ2以上に向上できる
ことが述べられているが、面内記録方式の場合は、この
ような技術を用いても本質的に互いに隣接する記録ビッ
トの磁化が互いに向き合っているため、境界に幅をもっ
た磁化遷移領域が形成され、１０Ｇｂ／ｉｎ2以上の面
記録密度を実現するためには技術的な困難が予想され
る。2. Description of the Related Art Magnetic disk drives currently in practical use employ an in-plane magnetic recording system. In the longitudinal magnetic recording method, it is a technical problem to form in-plane magnetic domains parallel to the substrate at high density on a longitudinal magnetic recording medium which is easily magnetized in a direction parallel to the disk substrate surface. As a method of increasing the recording density of the in-plane magnetic recording medium, a method of using a keeper medium having an extremely thin soft magnetic film formed on the surface of the recording medium having an easy axis of magnetization in the in-plane direction has been proposed.
This technology is, for example, the 41st Annual Conference onMagneti
Page 116 of abstracts published in sm & Magnetic Materials (November 12-15, 1996) (Article number D
Q-13) and page 133 (article number EB-12). It is stated that the adoption of such a medium structure can improve the areal recording density of magnetic recording to 1 Gb / in 2 or more using a self-recording / reproducing thin film head. However, even when such a technique is used, the magnetizations of recording bits that are essentially adjacent to each other face each other, so that a magnetization transition region having a width is formed at the boundary, and the areal recording density of 10 Gb / in 2 or more is obtained. Technical difficulties are expected to be realized.
【０００３】一方、垂直磁気記録方式は薄膜媒体の膜面
に垂直に磁化を形成する方式であり、記録原理や媒体ノ
イズの発現機構が従来の面内磁気記録媒体の場合とは異
なるが、隣接する磁化が互いに向き合わないため、本質
的に高密度磁気記録に適した方式として注目され、垂直
磁気記録に適した媒体の構造などが提案されている。Ｃ
ｏ合金材料からなる垂直磁化膜の垂直配向性を改善する
ために、垂直磁化膜と基板との間に非磁性材料下地を設
ける方法が検討されている。例えば、特開昭５８−７７
０２５号公報、特開昭５８−１４１４３５号公報にはＣ
ｏ−Ｃｒ磁性膜の下地層としてＴｉ膜を形成する方法
が、特開昭６０−２１４４１７号公報には下地層として
Ｇｅ，Ｓｉ材料を用いる方法が、特開昭６０−０６４４
１３号公報にはＣｏＯ，ＮｉＯ等の酸化物下地層材料が
開示されている。また、単磁極型の記録ヘッドと組み合
わせて用いられる垂直磁気記録媒体として、基板と垂直
磁化膜の間にパーマロイなどの軟磁性膜層を設けた媒体
が検討されている。[0003] On the other hand, the perpendicular magnetic recording system is a system in which magnetization is formed perpendicularly to the film surface of a thin film medium. Since the magnetizations do not face each other, attention has been paid to a method that is essentially suitable for high-density magnetic recording, and a medium structure suitable for perpendicular magnetic recording has been proposed. C
In order to improve the perpendicular orientation of a perpendicular magnetic film made of an o-alloy material, a method of providing a nonmagnetic material base between the perpendicular magnetic film and the substrate has been studied. For example, JP-A-58-77
No. 025 and JP-A-58-141435 disclose C
A method of forming a Ti film as an underlayer of an o-Cr magnetic film is disclosed in JP-A-60-214417, and a method of using a Ge or Si material as an underlayer is disclosed in JP-A-60-0644.
No. 13 discloses oxide underlayer materials such as CoO and NiO. As a perpendicular magnetic recording medium used in combination with a single-pole type recording head, a medium provided with a soft magnetic film layer such as permalloy between a substrate and a perpendicular magnetic film is being studied.
【０００４】[0004]
【発明が解決しようとする課題】１０Ｇｂ／ｉｎ2以上
の高密度磁気記録が可能な垂直磁気記録媒体には、線記
録密度分解能が大きいことに加えて媒体ノイズが小さい
ことが必要とされる。今までの報告例によると、例えば
第５回垂直磁気記録シンポジウム会議資料集（１９９６
年１０月２３−２５日）９５〜１００頁の「単層垂直磁
気ディスク媒体の高Ｓ／Ｎ化」と題する論文に記載され
ているように、垂直磁化膜の厚さを小さくする、垂直磁
化膜と基板の間に非磁性のＣｏＣｒ下地を導入する、あ
るいはＣｏ合金磁性膜の添加元素としてＴａ等の非磁性
元素を添加する、磁性結晶粒径を小さくすることが有効
であることが知られている。このような対策を施すこと
で媒体ノイズをかなりの程度低減できるが、更にノイズ
を低減できれば磁気記録装置の記録密度をより容易に伸
ばすことが可能となる。A perpendicular magnetic recording medium capable of high-density magnetic recording of 10 Gb / in 2 or more needs to have high linear recording density resolution and low medium noise. According to the reports so far, for example, the 5th perpendicular magnetic recording symposium conference materials (1996)
As described in a paper entitled "Higher S / N ratio of a single-layer perpendicular magnetic disk medium" on pages 95 to 100, a perpendicular magnetization method in which the thickness of a perpendicular magnetization film is reduced. It is known that it is effective to introduce a non-magnetic CoCr underlayer between the film and the substrate, or to add a non-magnetic element such as Ta as an additive element of the Co alloy magnetic film, and to reduce the magnetic crystal grain size. ing. By taking such measures, the medium noise can be reduced to a considerable extent, but if the noise can be further reduced, the recording density of the magnetic recording device can be more easily increased.
【０００５】本発明は、垂直磁気記録方式のこのような
現状に鑑みてなされたもので、１０Ｇｂ／ｉｎ2以上の
高記録密度を実現するための低ノイズ特性をもつ垂直磁
気記録媒体、及びその媒体を用いた高密度磁気記憶装置
を提供することを目的とする。The present invention has been made in view of such a situation of the perpendicular magnetic recording system, and has an object to realize a perpendicular magnetic recording medium having low noise characteristics for realizing a high recording density of 10 Gb / in 2 or more. An object is to provide a high-density magnetic storage device using a medium.
【０００６】[0006]
【課題を解決するための手段】垂直磁気記録媒体の記録
磁化状態を磁気力顕微鏡や走査型スピン電子検出型顕微
鏡によって調べた結果、大部分のノイズは媒体面に存在
する逆磁区や磁化のミクロ的な揺らぎが原因であること
が判明した。ミクロな磁化の揺らぎとは、媒体表面の磁
化の強さが０．２〜１０μｍ程度のミクロンレベルの距
離で場所によって変動していることを指す。媒体ノイズ
を減らすためには、逆磁区を減らすとともに、媒体の表
面に存在するミクロな磁化の揺らぎを減らさなければな
らない。As a result of examining the recording magnetization state of a perpendicular magnetic recording medium using a magnetic force microscope or a scanning spin electron detection microscope, most of the noise is detected in the reverse magnetic domain or the magnetization microstructure existing on the medium surface. Was found to be due to typical fluctuations. Micro-fluctuations in the magnetization indicate that the intensity of the magnetization on the medium surface fluctuates from place to place on a micron-level distance of about 0.2 to 10 μm. In order to reduce the medium noise, it is necessary to reduce the number of reverse magnetic domains and reduce the fluctuation of microscopic magnetization existing on the surface of the medium.
【０００７】本発明者らの実験の結果、以下の方法によ
って前記目的を達成できることが明かになった。垂直磁
化膜を一方向に垂直磁化すると媒体表面には強い反磁界
が作用する。この反磁界の作用で、垂直磁化した方向と
は逆の向きを持つ、いわゆる逆磁区が形成される。この
逆磁区の形成を妨げるためには、磁気異方性エネルギー
の大きい垂直磁化膜を採用する必要がある。磁気異方性
エネルギーとして、２．５×１０6ｅｒｇ／ｃｃ以上あ
ることが望ましい。実用的な媒体として扱いやすいＣｏ
合金材料を用いた垂直磁化膜の磁気異方性エネルギーの
最大値は、５×１０6ｅｒｇ／ｃｃである。この値以上
の磁気異方性エネルギーを持つＣｏ合金系規則格子材料
も存在するが、規則相を得るには５００℃以上のプロセ
ス温度が必要となるため、基板材料の選択範囲が狭まっ
たり、あるいは磁性膜を構成する結晶粒が粗大化してノ
イズを低減するのが困難になる等の問題が生ずる。Ｃｏ
合金以外のＰｔ／Ｃｏ，Ｐｄ／Ｃｏなどの多層膜からな
る垂直磁化膜、あるいはＴｂＦｅＣｏなどの希土類元素
を含む非晶質構造を持つ垂直磁化膜は、磁気異方性エネ
ルギーがいずれも２．５×１０6ｅｒｇ／ｃｃ以上であ
るため、本課題を達成する材料系としては望ましいが、
そのままでは面内方向の磁気的相互作用が大きく、媒体
ノイズが大きくなってしまうため媒体ノイズを減らす特
別な工夫が必要となる。As a result of experiments by the present inventors, it has been found that the above-mentioned object can be achieved by the following method. When the perpendicular magnetization film is perpendicularly magnetized in one direction, a strong demagnetizing field acts on the medium surface. By the action of this demagnetizing field, a so-called reverse magnetic domain having a direction opposite to the direction of perpendicular magnetization is formed. In order to prevent the formation of the reverse magnetic domain, it is necessary to employ a perpendicular magnetization film having a large magnetic anisotropy energy. The magnetic anisotropy energy is desirably 2.5 × 10 6 erg / cc or more. Co that is easy to handle as a practical medium
The maximum value of the magnetic anisotropy energy of the perpendicular magnetization film using the alloy material is 5 × 10 6 erg / cc. There are Co alloy-based ordered lattice materials having a magnetic anisotropy energy greater than this value, but a process temperature of 500 ° C. or more is required to obtain an ordered phase, so that the selection range of the substrate material is narrowed, or The crystal grains constituting the magnetic film become coarse, and it becomes difficult to reduce noise. Co
A perpendicular magnetic film composed of a multilayer film of Pt / Co or Pd / Co other than an alloy or a perpendicular magnetic film having an amorphous structure containing a rare earth element such as TbFeCo has a magnetic anisotropy energy of 2.5 or less. Since it is × 10 6 erg / cc or more, it is desirable as a material system to achieve this object,
The magnetic interaction in the in-plane direction is large if it is as it is, and the medium noise becomes large. Therefore, a special device for reducing the medium noise is required.
【０００８】磁気記録の面密度を１０Ｇｂ／ｉｎ2以上
とするためには、線記録密度として３００ｋＦＣＩ以上
が必要となる。この線記録密度に対応するビット長は８
３ｎｍである。記録を担う磁気記録媒体の厚さとして
は、リングヘッドの記録能力を考慮すると最短のビット
長より小さいことが望ましく、垂直磁化膜の膜厚を７０
ｎｍ以下に設定する必要がある。膜厚が５ｎｍ以下にな
ると、熱揺らぎのために記録磁化が不安定になるため、
垂直磁化膜の適当な膜厚範囲は５ｎｍ以上７０ｎｍ以下
である。In order to increase the areal density of magnetic recording to 10 Gb / in 2 or more, a linear recording density of 300 kFCI or more is required. The bit length corresponding to this linear recording density is 8
3 nm. The thickness of the magnetic recording medium for recording is preferably smaller than the shortest bit length in consideration of the recording performance of the ring head.
It needs to be set to nm or less. When the film thickness is 5 nm or less, the recording magnetization becomes unstable due to thermal fluctuation.
An appropriate thickness range of the perpendicular magnetization film is 5 nm or more and 70 nm or less.
【０００９】ノイズの原因となる逆磁区の大きさは、垂
直磁気記録媒体を構成する多結晶膜の粒径と結晶粒間の
磁気的相互作用の強さに依存する。逆磁区の大きさを３
００ｋＦＣＩのビット長以下とするためには、結晶粒径
の平均を１５ｎｍ以下とすることが必要であることが判
明した。しかし、結晶粒径が小さくなりすぎると記録媒
体の保磁力が減少して記録媒体として適さなくなるた
め、粒径は５ｎｍ以上であることが望まれる。なお、本
明細書で結晶粒径の平均とは、磁気記録媒体の表面で観
察した結晶粒が占有する面積と等しい円の直径の平均値
をいう。The size of the reverse magnetic domain that causes noise depends on the grain size of the polycrystalline film constituting the perpendicular magnetic recording medium and the strength of the magnetic interaction between the crystal grains. The size of the reverse domain is 3
It has been found that the average crystal grain size needs to be 15 nm or less in order to make the bit length of 00 kFCI or less. However, if the crystal grain size is too small, the coercive force of the recording medium decreases and the recording medium becomes unsuitable as a recording medium. Therefore, the grain size is desired to be 5 nm or more. In this specification, the average of the crystal grain diameters refers to the average value of the diameter of a circle having the same area as the area occupied by the crystal grains observed on the surface of the magnetic recording medium.
【００１０】磁気異方性エネルギーの高い垂直磁化膜を
用いることにより、逆磁区の発生を抑えることができる
ので、逆磁区に起因する媒体ノイズの発生を防ぐことが
できるが、媒体ノイズの他の原因として、媒体表面に存
在する磁化のミクロレベルでの揺らぎがある。この揺ら
ぎには、磁性膜の面内方向の磁気的相互作用が大きい場
合、長周期の磁化の揺らぎが生ずる。また、垂直磁化膜
表面に磁気的な不均質性が存在すると、短周期の磁化揺
らぎが生じ、いずれも媒体ノイズの原因となることが判
明した。このような長周期、短周期の磁化揺らぎを抑制
するためには、垂直磁化膜を２層構造とし、上層側に磁
気異方性エネルギー（Ｋｕ）の高い垂直磁化膜を下層側
に磁気異方性エネルギーが小さくてしかも結晶粒間の磁
気的分離が促進されている垂直磁化膜を採用すればよい
ことが分かった。上層側の垂直磁化膜は、２．５×１０
6ｅｒｇ／ｃｃ＜Ｋｕ＜５×１０6ｅｒｇ／ｃｃとし、下
層側の垂直磁化膜は、１×１０6ｅｒｇ／ｃｃ＜Ｋｕ＜
２．５×１０6ｅｒｇ／ｃｃとするのが有効である。The use of a perpendicular magnetic film having a high magnetic anisotropy energy can suppress the occurrence of reverse magnetic domains, thereby preventing the occurrence of medium noise caused by the reverse magnetic domains. As a cause, there is fluctuation at the micro level of the magnetization existing on the medium surface. When the magnetic interaction in the in-plane direction of the magnetic film is large, the fluctuation causes a long-period magnetization fluctuation. In addition, it has been found that when magnetic inhomogeneity exists on the surface of the perpendicular magnetization film, short-period magnetization fluctuation occurs, and all of them cause medium noise. In order to suppress such long-period and short-period magnetization fluctuations, the perpendicular magnetization film has a two-layer structure, and the perpendicular magnetization film having a high magnetic anisotropy energy (Ku) is provided on the upper layer side and the magnetic anisotropy is provided on the lower layer side. It has been found that a perpendicular magnetization film having a low kinetic energy and promoting magnetic separation between crystal grains may be used. 2.5 × 10
6 erg / cc <Ku <5 × 10 6 erg / cc, and the lower side perpendicular magnetization film is 1 × 10 6 erg / cc <Ku <
It is effective to set it to 2.5 × 10 6 erg / cc.
【００１１】ここで、下層側の垂直磁化膜はミクロレベ
ルの磁化の揺らぎピッチを記録に用いるビット長よりも
微細化する役目を果たし、上層側の垂直磁化膜は前述の
ように逆磁区の形成を抑制する。両者の膜厚の比は下層
側が厚いほうが膜全体から発生するノイズを抑えるため
には望ましく、下層の厚さは上層の２倍以上とするのが
好ましい。下層の厚さを上層の厚さの２倍未満にする
と、ミクロレベルの磁化揺らぎのピッチを記録に用いる
ビット長以下にする役目を十分果たさなくなるのであま
り望ましくない。The lower perpendicular magnetic film serves to make the fluctuation pitch of the magnetization on the micro level smaller than the bit length used for recording, and the upper perpendicular magnetic film forms the reverse magnetic domain as described above. Suppress. It is desirable that the ratio of the film thicknesses of both layers is thicker on the lower layer side in order to suppress noise generated from the entire film, and it is preferable that the thickness of the lower layer is twice or more the thickness of the upper layer. If the thickness of the lower layer is less than twice the thickness of the upper layer, the function of reducing the pitch of the magnetization fluctuation at the micro level to the bit length or less used for recording is not sufficiently performed, which is not desirable.
【００１２】下層垂直磁化膜としては、結晶粒径の平均
が５ｎｍ以上１５ｎｍ以下であること、結晶粒間の磁気
的結合を低減するために結晶粒界に２５ａｔ％以上の非
磁性元素が析出するかもしくは空隙が形成されているこ
とが望ましい。Ｃｏ合金に含まれる非磁性添加元素の総
量を２５ａｔ％以上にすると、その材料の飽和磁化が極
端に低下し、添加元素の種類によっては非磁性化する。
このような弱磁性もしくは非磁性層が存在すると、磁性
結晶粒間の磁気的結合力を下げ、この結果、媒体ノイズ
が低下する望ましい効果が生ずる。また、磁気記録膜が
強い垂直磁気異方性を持つためには、上層と下層の垂直
磁化膜の結晶格子が連続であること、すなわち成長整合
性が保たれていることが必要である。The lower perpendicular magnetization film has an average crystal grain size of 5 nm or more and 15 nm or less, and at least 25 at% of non-magnetic elements are precipitated at crystal grain boundaries to reduce magnetic coupling between crystal grains. Or it is desirable that a void is formed. If the total amount of the non-magnetic additive element contained in the Co alloy is 25 at% or more, the saturation magnetization of the material is extremely reduced, and the material becomes non-magnetic depending on the type of the additive element.
The presence of such a weakly magnetic or non-magnetic layer lowers the magnetic coupling force between the magnetic crystal grains, resulting in a desirable effect of reducing the medium noise. Further, in order for the magnetic recording film to have strong perpendicular magnetic anisotropy, it is necessary that the crystal lattices of the upper and lower perpendicular magnetic films are continuous, that is, that the growth consistency is maintained.
【００１３】また、媒体ノイズを下げるためには磁性結
晶粒間の磁気的結合力を下げることに加えて、垂直磁化
膜の膜厚方向の結晶粒を磁気的に分離もしくは結合力を
下げることも有効である。このためには、上下２層の垂
直磁化膜の間に非磁性もしくは飽和磁化が５０ｅｍｕ／
ｃｃ以下の弱磁性の中間層を導入することも有効であ
る。中間層の厚さは０．１ｎｍから５ｎｍの範囲が適当
である。中間層の厚さが０．１ｎｍ未満の場合、中間層
導入による十分な効果が得られず、逆に５ｎｍを超える
と媒体全体の保磁力が低下したりするため望ましくな
い。中間層に用いる材料は、Ｐｔ，Ｐｄ，Ｉｒ，Ｒｅ，
Ｒｕなどの単体金属及びこれらの元素を主成分とする合
金、あるいはＣｏに２５ａｔ％以上の前記元素あるいは
非磁性元素を添加した材料などが適当である。In order to reduce the medium noise, in addition to reducing the magnetic coupling force between the magnetic crystal grains, it is also necessary to magnetically separate or reduce the crystal force in the thickness direction of the perpendicular magnetization film. It is valid. For this purpose, non-magnetic or saturated magnetization between the upper and lower two perpendicular magnetization films is 50 emu /
It is also effective to introduce a weak magnetic intermediate layer of cc or less. The thickness of the intermediate layer is suitably in the range of 0.1 nm to 5 nm. When the thickness of the intermediate layer is less than 0.1 nm, a sufficient effect due to the introduction of the intermediate layer cannot be obtained, and when it exceeds 5 nm, the coercive force of the entire medium is undesirably reduced. Materials used for the intermediate layer are Pt, Pd, Ir, Re,
A single metal such as Ru and an alloy containing these elements as a main component, or a material obtained by adding 25 at% or more of the above elements or nonmagnetic elements to Co are suitable.
【００１４】また、垂直磁化膜の表面に形成される逆磁
区は、熱活性過程で時間の経過とともに反磁界の影響で
増大することがある。このような時間経過に伴って発生
する逆磁区の形成を抑えるためには、垂直磁化膜の表面
に厚さが０．１ｎｍから５ｎｍ程度の薄い金属膜を形成
するのが有効であることが、本発明者らの実験の結果明
らかになった。金属膜としては、Ｐｔ，Ｐｄ，Ｉｒ，Ｒ
ｅ，Ｒｕもしくはこれらの元素を主成分とする合金、あ
るいはＣｏもしくはＣｏ合金と前述の元素もしくはそれ
らの元素を主成分とする合金の積層膜、あるいは稀土類
元素を含む非晶質磁性材料膜、もしくはパーマロイ、Ｆ
ｅ−Ｓｉ，Ｆｅ−Ｓｉ−Ａｌ，Ｃｏ−Ｎｂ−Ｚｒなどの
軟磁性膜、あるいはＣｏ，Ｎｉ，Ｆｅ，Ｃｏ−Ｎｉ，Ｃ
ｏ−Ｎｉ−Ｃｒなどの面内磁化し易い磁性膜を用いるこ
とが可能である。垂直磁化膜表面にＣ，Ｂ，Ｎ，Ｐなど
の軽元素を拡散もしくは打ち込みすることにより、垂直
磁化膜をその膜厚方向に見て表面側の一部を軟磁性膜化
もしくは面内磁化膜化しても良い。Further, the reverse magnetic domains formed on the surface of the perpendicular magnetization film may increase due to the influence of the demagnetizing field with the lapse of time in the thermal activation process. In order to suppress the formation of reverse magnetic domains that occur with the passage of time, it is effective to form a thin metal film having a thickness of about 0.1 nm to 5 nm on the surface of the perpendicular magnetization film. As a result of the experiment of the present inventors, it became clear. Pt, Pd, Ir, R
e, Ru or an alloy containing these elements as main components, or a laminated film of Co or a Co alloy and the above-mentioned elements or alloys containing these elements as main components, or an amorphous magnetic material film containing rare earth elements; Or Permalloy, F
Soft magnetic films such as e-Si, Fe-Si-Al, Co-Nb-Zr, or Co, Ni, Fe, Co-Ni, C
It is possible to use a magnetic film such as o-Ni-Cr which is easily magnetized in the plane. By diffusing or implanting a light element such as C, B, N, or P into the surface of the perpendicular magnetic film, the surface of the perpendicular magnetic film is formed into a soft magnetic film or an in-plane magnetic film when viewed in the film thickness direction. May be used.
【００１５】以上をまとめると、本発明は次の通りであ
る。本発明は、非磁性基板上に下地層を介して形成した
垂直磁化膜を備える垂直磁気記録媒体において、下地層
は、六方稠密構造もしくは非晶質構造を持つ材料からな
り基板と接する第１下地層と、六方稠密構造を持ち優先
成長方位が［０００１］であってその上に形成される垂
直磁化膜と整合成長し得る材料からなる第２下地層とか
らなり、垂直磁化膜は第２下地層に接する下層垂直磁化
膜と上層垂直磁化膜とを含み、下層及び上層の垂直磁化
膜はＣｏ合金多結晶膜であって、上層垂直磁化膜は下層
垂直磁化膜より非磁性元素の総添加元素濃度が低く、か
つ飽和磁化（Ｍｓ）及び磁気異方性エネルギー（Ｋｕ）
が大きく、第２下地層から上層垂直磁化膜まで連続的に
整合成長が実現されており、垂直磁化膜の総厚が５ｎｍ
以上７０ｎｍ以下であり、上層垂直磁化膜の表面側で測
定した結晶粒の平均粒径が５ｎｍ以上１５ｎｍ以下であ
ることを特徴とする。In summary, the present invention is as follows. The present invention relates to a perpendicular magnetic recording medium having a perpendicular magnetic film formed on a non-magnetic substrate via an underlayer, wherein the underlayer is made of a material having a hexagonal close-packed structure or an amorphous structure, And a second underlayer made of a material having a hexagonal close-packed structure, a preferential growth direction of [0001], and capable of matching and growing with a perpendicular magnetic film formed thereon. The lower and upper perpendicular magnetic films include a lower perpendicular magnetic film and an upper perpendicular magnetic film that are in contact with the formation layer, and the lower and upper perpendicular magnetic films are Co alloy polycrystalline films. Low concentration, saturation magnetization (Ms) and magnetic anisotropy energy (Ku)
And the continuous growth from the second underlayer to the upper perpendicular magnetization film is realized, and the total thickness of the perpendicular magnetization film is 5 nm.
70 nm or less, and the average grain size of crystal grains measured on the surface side of the upper perpendicular magnetization film is 5 nm or more and 15 nm or less.
【００１６】下層垂直磁化膜と上層垂直磁化膜の間に六
方稠密構造を持つ非磁性もしくはＭｓ＜５０ｅｍｕ／ｃ
ｃの中間層を設け、第２下地層から上層垂直磁化膜まで
連続的に整合成長させてもよい。上層垂直磁化膜の上に
厚さ０．１ｎｍから５ｎｍの金属膜を形成してもよい。
この金属膜は、Ｐｔ，Ｐｄ，Ｉｒ，Ｒｅ，Ｒｕもしくは
これらの元素を主成分とする合金、あるいはＣｏもしく
はＣｏ合金とＰｔ，Ｐｄ，Ｉｒ，Ｒｅ，Ｒｕもしくはそ
れらの元素を主成分とする合金との積層膜、あるいは稀
土類元素を含む非晶質磁性材料膜とすることができる。Nonmagnetic or Ms <50 emu / c having a hexagonal close-packed structure between the lower perpendicular magnetization film and the upper perpendicular magnetization film
An intermediate layer c may be provided, and a continuous matching growth may be performed from the second underlayer to the upper perpendicular magnetization film. A metal film having a thickness of 0.1 nm to 5 nm may be formed on the upper perpendicular magnetization film.
This metal film is made of Pt, Pd, Ir, Re, Ru or an alloy mainly containing these elements, or Co or a Co alloy and an alloy mainly containing Pt, Pd, Ir, Re, Ru or these elements. Or an amorphous magnetic material film containing a rare earth element.
【００１７】下層垂直磁化膜は、その結晶粒界に２５ａ
ｔ％以上の非磁性元素の偏析層を持つ多結晶膜であるこ
とが好ましい。下層垂直磁化膜の磁気異方性エネルギー
Ｋｕが１×１０6ｅｒｇ／ｃｃ以上、２．５×１０6ｅｒ
ｇ／ｃｃ以下、上層垂直磁化膜の磁気異方性エネルギー
が２．５×１０6ｅｒｇ／ｃｃ以上、５×１０6ｅｒｇ／
ｃｃ以下であることが好ましい。第２下地層と下層垂直
磁化膜の格子定数の差は５％以下であることが好まし
い。下層垂直磁化膜の厚さは上層垂直磁化膜の厚さの２
倍以上であることが好ましい。The lower perpendicular magnetization film has a grain boundary of 25a.
It is preferably a polycrystalline film having a segregation layer of a nonmagnetic element of t% or more. The magnetic anisotropy energy Ku of the lower perpendicular magnetization film is 1 × 10 6 erg / cc or more and 2.5 × 10 6 er
g / cc or less, and the magnetic anisotropy energy of the upper perpendicular magnetization film is 2.5 × 10 6 erg / cc or more and 5 × 10 6 erg /
cc or less. The difference in lattice constant between the second underlayer and the lower perpendicular magnetization film is preferably 5% or less. The thickness of the lower perpendicular magnetization film is 2 times the thickness of the upper perpendicular magnetization film.
It is preferably at least two times.
【００１８】また、本発明は、磁気記録媒体と、磁気記
録媒体を駆動する磁気記録媒体駆動手段と、記録部と再
生部とを備える磁気ヘッドと、磁気ヘッドを駆動する磁
気ヘッド駆動手段と、磁気ヘッドの記録再生信号処理手
段とを含む磁気記憶装置において、磁気記録媒体として
前記した本発明による垂直磁気記録媒体を用い、磁気ヘ
ッドの再生部として磁気抵抗効果素子もしくは巨大磁気
抵抗効果素子を用い、面記録密度１０Ｇｂ／ｉｎ2以上
で磁気記録再生を行なうことを特徴とする。Further, the present invention provides a magnetic recording medium, a magnetic recording medium driving means for driving the magnetic recording medium, a magnetic head having a recording unit and a reproducing unit, a magnetic head driving means for driving the magnetic head, In a magnetic storage device including a magnetic head recording / reproducing signal processing means, the above-described perpendicular magnetic recording medium according to the present invention is used as a magnetic recording medium, and a magnetoresistive element or a giant magnetoresistive element is used as a reproducing section of the magnetic head. The magnetic recording and reproduction are performed at an areal recording density of 10 Gb / in 2 or more.
【００１９】さらに、本発明は、磁気記録媒体と、磁気
記録媒体を駆動する磁気記録媒体駆動手段と、記録部と
再生部とを備える磁気ヘッドと、磁気ヘッドを駆動する
磁気ヘッド駆動手段と、磁気ヘッドの記録再生信号処理
手段とを含む磁気記憶装置において、磁気記録媒体とし
て前記した本発明による垂直磁気記録媒体を用い、磁気
ヘッドの再生部として磁気トンネル効果を用いた素子を
用い、面記録密度３０Ｇｂ／ｉｎ2以上で磁気記録再生
を行なうことを特徴とする。Further, the present invention provides a magnetic recording medium, a magnetic recording medium driving means for driving the magnetic recording medium, a magnetic head having a recording section and a reproducing section, a magnetic head driving means for driving the magnetic head, In a magnetic storage device including a recording / reproduction signal processing means for a magnetic head, the perpendicular magnetic recording medium according to the present invention described above is used as a magnetic recording medium, and an element using a magnetic tunnel effect is used as a reproduction section of the magnetic head. The magnetic recording / reproducing is performed at a density of 30 Gb / in 2 or more.
【００２０】[0020]
【発明の実施の形態】以下、図面を参照して本発明の実
施の形態を説明する。図１は、本発明による垂直磁気記
録媒体の第１の実施の形態を示す断面模式図である。こ
の垂直磁気記録媒体は、非磁性基板１１上に磁性膜の垂
直配向性向上や結晶粒径制御を目的とした下地層１２，
１３を介して垂直磁化膜が形成される。基板側に形成さ
れる第１下地層１２は、六方稠密構造をもつ第２下地層
１３の成長方位が［０００１］方位となるよう膜の核生
成過程を制御する役割を果たす。この目的に適当な材料
は、Ｔｉ，Ｒｕあるいはこれらの元素を主成分としてＣ
ｒ，Ｖ，Ｍｏ，Ｗなどの添加元素を含む六方稠密構造を
持つ材料、Ｓｉ，Ｇｅあるいはこれらの元素を主成分と
する非晶質材料が適当である。Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic sectional view showing a first embodiment of a perpendicular magnetic recording medium according to the present invention. This perpendicular magnetic recording medium includes an underlayer 12 on a nonmagnetic substrate 11 for the purpose of improving the perpendicular orientation of a magnetic film and controlling the crystal grain size.
A perpendicular magnetization film is formed through the intermediation of the perpendicular magnetization film 13. The first underlayer 12 formed on the substrate side has a role of controlling the nucleation process of the film such that the growth orientation of the second underlayer 13 having the hexagonal close-packed structure becomes the [0001] orientation. Materials suitable for this purpose are Ti, Ru or C
A material having a hexagonal close-packed structure containing additional elements such as r, V, Mo, and W, Si, Ge, or an amorphous material containing these elements as main components is suitable.
【００２１】第２下地層１３は、六方稠密構造を持つ非
磁性もしくは飽和磁化ＭｓがＭｓ＜５０ｅｍｕ／ｃｃ以
下の弱磁性の材料であり、例えばＣｏに２５ａｔ％以上
のＣｒ，Ｖ，Ｍｏ，Ｗ，Ｎｂ，Ｒｅ，Ｔｉ，Ｙ等の非磁
性元素を添加した材料が用いられる。この材料の磁化強
度が５０ｅｍｕ／ｃｃ以上となると記録再生時の分解能
を下げたり、ノイズが上昇したりするため望ましくな
い。この第２下地層はその上に形成される垂直磁化膜１
４と成長整合することになり、良好な整合成長を実現す
るためには、両者の格子定数の差を５％以下とする必要
がある。格子定数の差が５％以上になると、ミスフィッ
ト転位が導入されたり、磁性膜に歪が入り、磁気異方性
を低下させることになり、望ましくない。The second underlayer 13 is made of a nonmagnetic material having a hexagonal close-packed structure or a weak magnetic material having a saturation magnetization Ms of Ms <50 emu / cc or less. , Nb, Re, Ti, Y, and other non-magnetic elements are used. If the magnetization intensity of this material is 50 emu / cc or more, it is not desirable because the resolution at the time of recording / reproduction is reduced or noise is increased. The second underlayer is a perpendicular magnetic film 1 formed thereon.
4, and the difference in lattice constant between the two must be 5% or less in order to realize good matching growth. If the difference between the lattice constants is 5% or more, misfit dislocations are introduced, or the magnetic film is distorted, thereby lowering the magnetic anisotropy, which is not desirable.
【００２２】磁性膜としては、合金元素としてＣｒ，Ｔ
ａ，Ｐｔ，Ｐｄ，Ｓｉ，Ｖ，Ｎｂ，Ｗ，Ｍｏ，Ｈｆ，Ｒ
ｅ，Ｚｒ，Ｂ，Ｐ，Ｒｕなどから選ばれたすくなくとも
１種の元素を含むＣｏ合金が用いられる。この例では、
組成の異なる垂直磁化膜を上下に２層積層する。下層垂
直磁化膜１４は、上層垂直磁性膜１５に比べてＣｏに添
加する非磁性元素の総量を多くすることにより、磁気異
方性エネルギーＫｕを小さく調整すると同時に結晶粒界
により多くの非磁性元素の析出を行なわせるものであ
る。上層垂直磁化膜１５は下層垂直磁化膜１４と成長整
合性を保って形成され、結晶的には第２下地層１３から
上層垂直磁化膜１５表面まで連続した結晶成長が実現さ
れることになる。The magnetic film is made of Cr, T as an alloying element.
a, Pt, Pd, Si, V, Nb, W, Mo, Hf, R
A Co alloy containing at least one element selected from e, Zr, B, P, and Ru is used. In this example,
Two layers of perpendicular magnetic films having different compositions are vertically stacked. The lower perpendicular magnetization film 14 adjusts the magnetic anisotropy energy Ku to be small by increasing the total amount of nonmagnetic elements added to Co as compared with the upper perpendicular magnetic film 15, and at the same time, increases the number of nonmagnetic elements in the crystal grain boundaries. Is caused to precipitate. The upper perpendicular magnetic film 15 is formed while maintaining the growth consistency with the lower perpendicular magnetic film 14, and crystallographically, continuous crystal growth from the second underlayer 13 to the surface of the upper perpendicular magnetic film 15 is realized.
【００２３】この磁性膜は多結晶膜であり、高い線記録
密度特性と低いノイズ特性をもたせるために、結晶粒径
平均は１５ｎｍ以下で、しかも特に下層垂直磁化膜１４
の結晶粒界面には非磁性元素が優先的に偏析した構造が
用いられる。この垂直磁化膜は膜面方向では、結晶粒界
に偏析層が存在するために、磁気結合力は小さい。媒体
ノイズを低減するために、既に述べたように、この垂直
磁化膜の上に磁気異方性エネルギーＫｕが相対的に大き
い上層垂直磁化膜１５を形成する。上層垂直磁化膜１５
の表面には保護膜１６が形成される。This magnetic film is a polycrystalline film, and has an average crystal grain size of 15 nm or less and, in particular, a lower perpendicular magnetization film 14 in order to provide high linear recording density characteristics and low noise characteristics.
A structure in which nonmagnetic elements are preferentially segregated is used at the crystal grain interface. This perpendicular magnetization film has a small magnetic coupling force in the direction of the film surface because a segregation layer exists at the crystal grain boundary. In order to reduce the medium noise, as described above, the upper perpendicular magnetic film 15 having a relatively large magnetic anisotropy energy Ku is formed on the perpendicular magnetic film. Upper layer perpendicular magnetization film 15
A protective film 16 is formed on the surface of the substrate.
【００２４】図２から図４は、本発明による垂直磁気記
録媒体の他の実施の形態を示す断面模式図である。図２
に断面構造を示した第２の実施の形態の垂直磁気記録媒
体は、非磁性基板２１上に第１下地層２２、第２下地層
２３からなる２層の下地層を形成し、その上に磁性膜を
形成したものである。磁性膜は、下層垂直磁化膜２４と
上層垂直磁化膜２６からなる２層の積層した垂直磁化膜
の間に六方稠密構造を持つ非磁性もしくは飽和磁化Ｍｓ
がＭｓ＜５０ｅｍｕ／ｃｃの弱磁性を持つ中間層２５を
設けたものであり、媒体のノイズ低減を促進する効果が
ある。FIGS. 2 to 4 are schematic sectional views showing another embodiment of the perpendicular magnetic recording medium according to the present invention. FIG.
In the perpendicular magnetic recording medium according to the second embodiment, the cross-sectional structure of which is shown in FIG. 2, a two-layer underlayer consisting of a first underlayer 22 and a second underlayer 23 is formed on a non-magnetic substrate 21, and A magnetic film is formed. The magnetic film is made of a nonmagnetic or saturated magnetic material Ms having a hexagonal close-packed structure between two stacked perpendicular magnetic films composed of a lower perpendicular magnetic film 24 and an upper perpendicular magnetic film 26.
Is provided with an intermediate layer 25 having a weak magnetic property of Ms <50 emu / cc, and has an effect of promoting noise reduction of a medium.
【００２５】中間層２５は、上下の垂直磁化膜２４，２
６と結晶的には整合成長している。中間層の厚さは０．
５ｎｍ以上５ｎｍ以下が望ましく、さらに望ましい厚さ
の範囲は１ｎｍ以上３ｎｍ以下である。このような構造
を採用することにより、垂直磁化膜の結晶粒径や配向の
高度制御が可能になり、更なる低ノイズ特性を実現する
ことができる。上層垂直磁化膜２６の表面には保護膜２
７を形成する。第１下地層２２、第２下地層２３、下層
垂直磁化膜２４、上層垂直磁化膜２６などの材料には、
図１に示した第１の実施の形態の媒体構造と対応する部
分の材料と同じ材料を用いることができる。The intermediate layer 25 is composed of upper and lower perpendicular magnetization films 24, 2
6 is grown in a crystalline manner. The thickness of the intermediate layer is 0.
The thickness is preferably 5 nm or more and 5 nm or less, and a more desirable thickness range is 1 nm or more and 3 nm or less. By adopting such a structure, the crystal grain size and orientation of the perpendicular magnetization film can be highly controlled, and further low noise characteristics can be realized. The protective film 2 is formed on the surface of the upper perpendicular magnetization film 26.
7 is formed. Materials such as the first underlayer 22, the second underlayer 23, the lower perpendicular magnetization film 24, and the upper perpendicular magnetization film 26 include:
The same material as the material of the portion corresponding to the medium structure of the first embodiment shown in FIG. 1 can be used.
【００２６】図３に示した本発明の第３の実施の形態の
媒体構造は、第１図に示した第１の実施の形態の垂直磁
気記録媒体の磁性膜の上に金属膜３６を設けたものに相
当する。すなわち、この媒体構造は、非磁性基板３１上
に第１下地層３１、第２下地層３３からなる２層の下地
層を設け、その上に下層垂直磁化膜３４、上層垂直磁化
膜３５からなる２層構造の垂直磁化膜を用いる。上層垂
直磁化膜３５の上に金属膜３６を形成し、その上に保護
膜３７を形成する。下地層や垂直磁化膜の材料には、第
１の実施の形態で述べた材料を用いることができる。金
属膜３６としては、Ｐｔ，Ｐｄ，Ｉｒ，Ｒｅ，Ｒｕもし
くはこれらの元素を主成分とする合金、あるいはＣｏも
しくはＣｏ合金と前述の元素もしくはそれらの元素を主
成分とする合金の積層膜、あるいは稀土類元素を含む非
晶質磁性材料膜を用いる。In the medium structure of the third embodiment of the present invention shown in FIG. 3, a metal film 36 is provided on the magnetic film of the perpendicular magnetic recording medium of the first embodiment shown in FIG. Equivalent to In other words, this medium structure is provided with a two-layer underlayer consisting of a first underlayer 31 and a second underlayer 33 on a non-magnetic substrate 31, and a lower perpendicular magnetization film 34 and an upper perpendicular magnetization film 35 thereon. A perpendicular magnetization film having a two-layer structure is used. A metal film 36 is formed on the upper perpendicular magnetization film 35, and a protective film 37 is formed thereon. The materials described in the first embodiment can be used for the material of the underlayer and the perpendicular magnetization film. As the metal film 36, Pt, Pd, Ir, Re, Ru or an alloy containing these elements as a main component, or a laminated film of Co or a Co alloy and the above-described elements or an alloy containing these elements as a main component, or An amorphous magnetic material film containing a rare earth element is used.
【００２７】図４に示した本発明の第４の実施の形態の
媒体構造は、図２に示した第２の実施の形態の垂直磁気
記録媒体の磁性膜の上に金属膜４７を設けたものに相当
する。図４の非磁性基板４１、第１下地層４２、第２下
地層４３、下層垂直磁化膜４４、中間層４５、上層垂直
磁化膜４６、保護膜４８は、図２の非磁性基板２１、第
１下地層２２、第２下地層２３、下層垂直磁化膜２４、
中間層２５、上層垂直磁化膜２６、保護膜２７にそれぞ
れ対応する。金属膜４８としては、Ｐｔ，Ｐｄ，Ｉｒ，
Ｒｅ，Ｒｕもしくはこれらの元素を主成分とする合金、
あるいはＣｏもしくはＣｏ合金と前述の元素もしくはそ
れらの元素を主成分とする合金の積層膜、あるいは稀土
類元素を含む非晶質磁性材料膜を用いる。In the medium structure according to the fourth embodiment of the present invention shown in FIG. 4, a metal film 47 is provided on the magnetic film of the perpendicular magnetic recording medium according to the second embodiment shown in FIG. Equivalent to something. The nonmagnetic substrate 41, the first underlayer 42, the second underlayer 43, the lower perpendicular magnetic film 44, the intermediate layer 45, the upper perpendicular magnetic film 46, and the protective film 48 of FIG. 1 underlayer 22, second underlayer 23, lower perpendicular magnetization film 24,
They correspond to the intermediate layer 25, the upper perpendicular magnetization film 26, and the protective film 27, respectively. As the metal film 48, Pt, Pd, Ir,
Re, Ru or alloys containing these elements as main components,
Alternatively, a laminated film of Co or a Co alloy and the above-described elements or alloys containing these elements as main components, or an amorphous magnetic material film containing a rare earth element is used.
【００２８】図１から図４に示す媒体構造を採用するこ
とにより、垂直磁化膜の表面に存在する長周期、短周期
の磁気揺らぎが減少し、かつミクロな磁化揺らぎのピッ
チが記録ビット長より短くなり、媒体ノイズが低減す
る。以下、本発明を実施例により更に詳細に説明する。By employing the medium structure shown in FIGS. 1 to 4, long-period and short-period magnetic fluctuations existing on the surface of the perpendicular magnetization film are reduced, and the pitch of the microscopic magnetic fluctuations is smaller than the recording bit length. And the media noise is reduced. Hereinafter, the present invention will be described in more detail with reference to examples.
【００２９】［実施例１］直径２．５インチのガラス基
板を用いて、直流マグネトロンスパッタ法によって、図
１に示す断面構造を持つ磁気記録媒体を作製した。基板
１１上に、下地層１２，１３、垂直磁化膜１４，１５、
保護膜１６をこの順序で形成した。第１下地用にはＴｉ
−１０．２ａｔ％Ｃｒターゲット、第２下地用にはＣｏ
−３４ａｔ％Ｃｒターゲット、下層垂直磁化膜用にＣｏ
−１７ａｔ％Ｃｒ−５ａｔ％Ｔａターゲット、上層垂直
磁化膜用にＣｏ−１０ａｔ％Ｃｒ−１０ａｔ％Ｐｔター
ゲット、保護膜用にカーボンターゲットを用いた。スパ
ッタのＡｒガス圧力を３ｍＴｏｒｒ、スパッターパワー
を１０Ｗ／ｃｍ2、基板温度を２５０℃とした条件でＣ
ｒＴｉ膜を３０ｎｍ、Ｃｏ−Ｃｒ膜を３０ｎｍ、下層垂
直磁化膜を３０ｎｍ、上層垂直磁化膜を２ｎｍ、カーボ
ン膜を１０ｎｍの厚さ形成した。同様な条件で、上層垂
直磁化膜の厚さを５ｎｍ，１０ｎｍ，１５ｎｍ，２０ｎ
ｍ，３０ｎｍ，４０ｎｍとした以外は前記と同様な垂直
媒体を作製した。Example 1 A magnetic recording medium having a cross-sectional structure shown in FIG. 1 was manufactured by a DC magnetron sputtering method using a glass substrate having a diameter of 2.5 inches. On a substrate 11, underlayers 12 and 13, perpendicular magnetization films 14 and 15,
The protective film 16 was formed in this order. Ti for the first base
-10.2 at% Cr target, Co for the second underlayer
-34 at% Cr target, Co for lower perpendicular magnetization film
A -17 at% Cr-5 at% Ta target, a Co-10 at% Cr-10 at% Pt target for the upper perpendicular magnetization film, and a carbon target for the protective film were used. Ar gas pressure for sputtering is 3 mTorr, sputtering power is 10 W / cm 2 , and substrate temperature is 250 ° C.
The thickness of the rTi film was 30 nm, the thickness of the Co-Cr film was 30 nm, the thickness of the lower perpendicular magnetization film was 30 nm, the thickness of the upper perpendicular magnetization film was 2 nm, and the thickness of the carbon film was 10 nm. Under the same conditions, the thickness of the upper perpendicular magnetization film is set to 5 nm, 10 nm, 15 nm, and 20 n.
A perpendicular medium similar to the above was prepared, except that m, 30 nm and 40 nm were used.
【００３０】比較試料として、上層垂直磁化膜を設けな
い垂直磁気記録媒体及び上層垂直膜の膜厚を５０ｎｍと
した垂直磁気記録媒体を作製した。上層及び下層垂直磁
化膜の磁気特性を測定した結果、下層垂直磁化膜：Ｍｓ
＝３８５ｅｍｕ／ｃｃ，Ｋｕ＝１．８×１０6ｅｒｇ／
ｃｃ、上層垂直磁化膜：Ｍｓ＝６７５ｅｍｕ／ｃｃ，Ｋ
ｕ＝４．１×１０6ｅｒｇ／ｃｃであった。第２下地層
１３の飽和磁化は、Ｍｓ＝１２ｅｍｕ／ｃｃであった。
これらの垂直磁化膜の結晶粒径は、８〜１４ｎｍであ
り、結晶粒間には２６〜２８ａｔ％のＣｒが平均厚さ１
ｎｍの幅で偏析していることを電子顕微鏡を用いた分析
で確認した。また、第２下地層１３と下層垂直磁化膜１
４の格子定数の差は３．２％であった。As comparative samples, a perpendicular magnetic recording medium having no upper perpendicular magnetic film and a perpendicular magnetic recording medium having an upper perpendicular film with a thickness of 50 nm were prepared. As a result of measuring the magnetic properties of the upper and lower perpendicular magnetic films, the lower perpendicular magnetic film: Ms
= 385 emu / cc, Ku = 1.8 × 10 6 erg /
cc, upper perpendicular magnetization film: Ms = 675 emu / cc, K
u = 4.1 × 10 6 erg / cc. The saturation magnetization of the second underlayer 13 was Ms = 12 emu / cc.
The crystal grain size of these perpendicular magnetization films is 8 to 14 nm, and 26 to 28 at% of Cr has an average thickness of 1 between crystal grains.
It was confirmed by analysis using an electron microscope that the particles were segregated in a width of nm. The second underlayer 13 and the lower perpendicular magnetization film 1
The difference in lattice constant of No. 4 was 3.2%.
【００３１】これらの磁気記録媒体の記録再生特性を、
記録再生分離型の磁気ヘッドを用いて評価した。記録ヘ
ッドのギャップ長は０．２ｍｍ、再生用の磁気抵抗効果
型（ＭＲ）ヘッドのシールド間隔は０．２ｍｍ、測定時
のスペーシングは０．０６ｍｍとした。記録密度は低周
波の再生出力の半分になる出力半減記録密度（Ｄ50）を
測定して評価し、２０ｋＦＣＩの磁気記録を行なった場
合のＳ／Ｎは、上層垂直磁化膜のない比較試料のＳ／Ｎ
に対する相対値で評価した。これらの結果を表１に示
す。The recording and reproducing characteristics of these magnetic recording media are
The evaluation was performed using a recording / reproducing separation type magnetic head. The gap length of the recording head was 0.2 mm, the shield interval of the magnetoresistive (MR) head for reproduction was 0.2 mm, and the spacing at the time of measurement was 0.06 mm. The recording density was evaluated by measuring the output half-reduced recording density (D 50 ) at which half of the low-frequency reproduction output was obtained. S / N
The relative value was evaluated. Table 1 shows the results.
【００３２】[0032]
【表１】 [Table 1]
【００３３】本実施例の磁気記録媒体は、比較例に比べ
て出力半減記録密度Ｄ50が大幅に向上し、しかも媒体Ｓ
／Ｎが向上しており、高密度磁気記録媒体として望まし
いことがわかった。本実施例で作製した磁気記録媒体を
用いて、再生素子としてＭＲヘッドを用いた２．５イン
チの磁気記録再生装置を作製した。面記録密度１０Ｇｂ
／ｉｎ2の条件でエラーレート１０-9が確保でき、超高
密度記録再生装置として動作することを確認した。In the magnetic recording medium of this embodiment, the output half-reduction recording density D 50 is greatly improved as compared with the comparative example, and the medium S
/ N has been improved, indicating that it is desirable as a high-density magnetic recording medium. Using the magnetic recording medium manufactured in this example, a 2.5-inch magnetic recording and reproducing apparatus using an MR head as a reproducing element was manufactured. Surface recording density 10Gb
It was confirmed that an error rate of 10 -9 could be secured under the condition of / in 2 and that the device operated as an ultra-high density recording / reproducing apparatus.
【００３４】［実施例２］直径２．５インチのシリコン
基板を用いて、直流マグネトロンスパッタ法によって、
図２に示す断面構造を持つ垂直磁気記録媒体を作製し
た。基板２１上に、第１下地層２２、第２下地層２３、
下層垂直磁化膜２４、中間層２５、上層垂直磁化膜２
６、保護膜２７をこの順序で形成した。第１下地用には
Ｇｅターゲット、第２下地用にはＣｏ−３５ａｔ％Ｒｕ
ターゲット、下層垂直磁化膜用にはＣｏ−１５ａｔ％Ｃ
ｒ−６ａｔ％Ｐｔ−３ａｔ％Ｙターゲット、中間層用に
はＣｏ−４５ａｔ％Ｒｕターゲット、上層垂直磁化膜用
にはＣｏ−１４ａｔ％Ｃｒ−８ａｔ％Ｐｔターゲット、
保護膜用にはカーボンターゲットを用いた。Example 2 Using a 2.5 inch diameter silicon substrate, a DC magnetron sputtering method was used.
A perpendicular magnetic recording medium having the cross-sectional structure shown in FIG. 2 was manufactured. On a substrate 21, a first underlayer 22, a second underlayer 23,
Lower perpendicular magnetization film 24, intermediate layer 25, upper perpendicular magnetization film 2
6. The protective film 27 was formed in this order. Ge target for the first underlayer, Co-35 at% Ru for the second underlayer
Co-15at% C for target and lower perpendicular magnetization film
an r-6 at% Pt-3 at% Y target, a Co-45 at% Ru target for the intermediate layer, a Co-14 at% Cr-8 at% Pt target for the upper perpendicular magnetization film,
A carbon target was used for the protective film.
【００３５】Ｃｏ−３５ａｔ％Ｒｕの飽和磁化は１５ｅ
ｍｕ／ｃｃ以下であり、弱磁性膜が得られる。スパッタ
のＡｒガス圧力を３ｍＴｏｒｒ、スパッターパワーを１
０Ｗ／ｃｍ2、基板温度を２８０℃とした条件でＧｅ膜
を３０ｎｍ、Ｃｏ−Ｒｕ膜を１５ｎｍ、下層垂直磁化膜
を３０ｎｍ、中間層を０．１ｎｍ、上層垂直磁化膜のＣ
ｏ−Ｃｒ−Ｐｔ膜を２ｎｍ、カーボン膜を１０ｎｍの厚
さ形成し、図２に断面構造を示す垂直磁気記録媒体を形
成した。さらに、中間層２５の膜厚を１ｎｍ，２ｎｍ，
３ｎｍ，５ｎｍとした以外は同様の垂直媒体を作製し
た。The saturation magnetization of Co-35 at% Ru is 15 e
mu / cc or less, and a weak magnetic film can be obtained. Ar gas pressure for sputtering is 3 mTorr and sputtering power is 1
Under the conditions of 0 W / cm 2 and a substrate temperature of 280 ° C., the Ge film is 30 nm, the Co—Ru film is 15 nm, the lower perpendicular magnetization film is 30 nm, the intermediate layer is 0.1 nm, and the upper perpendicular magnetization film is C.
An o-Cr-Pt film was formed to a thickness of 2 nm and a carbon film was formed to a thickness of 10 nm to form a perpendicular magnetic recording medium whose sectional structure is shown in FIG. Further, the thickness of the intermediate layer 25 is set to 1 nm, 2 nm,
A similar perpendicular medium was prepared except that the thickness was 3 nm and 5 nm.
【００３６】また、比較試料として、上層垂直磁化膜形
成に用いたＣｏ−Ｃｒ−Ｐｔ膜３５ｎｍからなる単層垂
直磁気記録媒体を作製した。比較試料の下地と保護膜の
形成条件は上記実施例と同様とした。上層及び下層垂直
磁化膜の磁気特性を測定した結果、下層垂直磁化膜：Ｍ
ｓ＝３７０ｅｍｕ／ｃｃ，Ｋｕ＝２．０×１０6ｅｒｇ
／ｃｃ、上層垂直磁化膜：Ｍｓ＝６００ｅｍｕ／ｃｃ，
Ｋｕ＝４．３×１０6ｅｒｇ／ｃｃであった。中間層２
５のＭｓ＝０ｅｍｕ／ｃｃであった。上層垂直磁化膜の
表面で測定した結晶粒の平均粒径は１１ｎｍであり、下
層垂直磁化膜の結晶粒界には２７ａｔ％のＣｒが平均厚
さ１．２ｎｍの幅で偏析していることを電子顕微鏡を用
いた分析で確認した。また、第２下地層２３と下層垂直
磁化膜２４の格子定数の差は３％であった。As a comparative sample, a single-layer perpendicular magnetic recording medium comprising a 35 nm Co-Cr-Pt film used for forming the upper perpendicular magnetic film was manufactured. The conditions for forming the underlayer and the protective film of the comparative sample were the same as those in the above example. As a result of measuring the magnetic properties of the upper and lower perpendicular magnetic films, the lower perpendicular magnetic film: M
s = 370 emu / cc, Ku = 2.0 × 10 6 erg
/ Cc, upper perpendicular magnetization film: Ms = 600 emu / cc,
Ku = 4.3 × 10 6 erg / cc. Middle layer 2
Ms of 5 = 0 emu / cc. The average grain size of the crystal grains measured on the surface of the upper perpendicular magnetic film is 11 nm, and 27 at% of Cr is segregated at the grain boundary of the lower perpendicular magnetic film with an average thickness of 1.2 nm. It was confirmed by analysis using an electron microscope. The difference in lattice constant between the second underlayer 23 and the lower perpendicular magnetization film 24 was 3%.
【００３７】これらの磁気記録媒体の保磁力Ｈｃと記録
再生特性の評価を、それぞれ振動型磁力計（ＶＳＭ）、
記録再生分離型の磁気ヘッドを用いて行なった。記録ヘ
ッドのギャップ長は０．２ｍｍ、再生用の巨大磁気抵抗
効果型（ＧＭＲ）ヘッドのシールド間隔は０．１５ｍ
ｍ、測定時のスペーシングは０．０４ｍｍとした。記録
密度は低周波の再生出力の半分になる出力半減記録密度
（Ｄ50）を測定して評価し、２０ｋＦＣＩの磁気記録を
行なった場合のシグナルとノイズの比率Ｓ／Ｎは、比較
試料のＳ／Ｎに対する相対値によって評価した。これら
の結果を表２に示す。Evaluations of the coercive force Hc and the recording / reproducing characteristics of these magnetic recording media were performed using a vibrating magnetometer (VSM) and
The recording and reproduction were performed using a separated magnetic head. The gap length of the recording head is 0.2 mm, and the shield distance of the giant magnetoresistive (GMR) head for reproduction is 0.15 m.
m, and the spacing at the time of measurement was 0.04 mm. The recording density was evaluated by measuring the output half-reduced recording density (D 50 ), which is half of the low-frequency reproduction output. / N. Table 2 shows the results.
【００３８】[0038]
【表２】 [Table 2]
【００３９】本実施例の垂直磁気記録媒体は、比較例に
比べてＤ50，Ｓ／Ｎが大幅に改善されており、高密度磁
気記録媒体として望ましいことがわかった。本実施例で
作製した垂直磁気記録媒体を用いて、再生素子としてＧ
ＭＲヘッドを用いた２．５インチの磁気記録再生装置を
作製した。面記録密度２０Ｇｂ／ｉｎ2の条件でエラー
レート１０-9が確保でき、超高密度記録再生装置として
動作することを確認した。The perpendicular magnetic recording medium of this embodiment has a significantly improved D 50 and S / N as compared with the comparative example, indicating that it is desirable as a high-density magnetic recording medium. Using the perpendicular magnetic recording medium manufactured in this example, G
A 2.5-inch magnetic recording / reproducing apparatus using an MR head was manufactured. It was confirmed that an error rate of 10 -9 could be secured under the condition of a surface recording density of 20 Gb / in 2 , and that the device operated as an ultra-high density recording / reproducing apparatus.
【００４０】［実施例３］直径２．５インチのガラス基
板を用いて、直流マグネトロンスパッタ法によって、図
３に示す断面構造を持つ垂直磁気記録媒体を作製した。
基板３１上に、第１下地層３２、第２下地層３３、下層
垂直磁化膜３４、上層垂直磁化膜３５、金属膜３６、保
護膜３７をこの順序で形成した。第１下地層用にはＴｉ
ターゲット、第２下地層用にはＣｏ−３０ａｔ％Ｃｒ−
１０ａｔ％Ｒｕターゲット、下層垂直磁化膜用にはＣｏ
−１７ａｔ％Ｃｒ−１ａｔ％Ｙ−３ａｔ％Ｔａターゲッ
ト、上層垂直磁化膜用にはＣｏ−１８ａｔ％Ｃｒ−１０
ａｔ％Ｐｔターゲット、金属膜用にはＰｔターゲット、
保護膜用にはカーボンターゲットを用いた。スパッタの
Ａｒガス圧力を３ｍＴｏｒｒ、スパッターパワーを１０
Ｗ／ｃｍ2、基板温度を２５０℃とした条件でＴｉ膜を
３０ｎｍ、Ｃｏ−Ｃｒ−Ｒｕ膜を２０ｎｍ、Ｃｏ−Ｃｒ
−Ｙ−Ｔａ膜を２０ｎｍ、Ｃｏ−Ｃｒ−Ｐｔ膜を１ｎ
ｍ、Ｐｔ膜を０．５ｎｍ、カーボン膜を７ｎｍの厚さ形
成した。Example 3 Using a glass substrate having a diameter of 2.5 inches, a perpendicular magnetic recording medium having a sectional structure shown in FIG. 3 was produced by a DC magnetron sputtering method.
A first underlayer 32, a second underlayer 33, a lower perpendicular magnetization film 34, an upper perpendicular magnetization film 35, a metal film 36, and a protective film 37 were formed in this order on a substrate 31. Ti for the first underlayer
Co-30 at% Cr- for the target and second underlayer
10 at% Ru target, Co for lower perpendicular magnetization film
-17 at% Cr-1 at% Y-3 at% Ta target, Co-18 at% Cr-10 for upper perpendicular magnetization film
at% Pt target, Pt target for metal film,
A carbon target was used for the protective film. Ar gas pressure for sputtering is 3 mTorr and sputtering power is 10
W / cm 2 , a substrate temperature of 250 ° C., a Ti film of 30 nm, a Co—Cr—Ru film of 20 nm, and a Co—Cr film
-Y-Ta film is 20 nm, Co-Cr-Pt film is 1 n
m, a Pt film was formed to a thickness of 0.5 nm, and a carbon film was formed to a thickness of 7 nm.
【００４１】金属膜３６としてＰｔ膜の代わりに、Ｐｄ
膜（１ｎｍ）、Ｉｒ膜（１．５ｎｍ）、Ｒｅ膜（０．１
ｎｍ）、Ｒｕ膜（１．２ｎｍ）、及びＣｏ／Ｐｔ多層膜
（３ｎｍ）を形成した以外は前記と同様な垂直磁気記録
媒体を作製した。ここでＣｏ／Ｐｔ多層膜は、Ｃｏター
ゲットとＰｔターゲットを交互に用いてそれぞれ０．５
ｎｍの厚さずつ６サイクル形成し、合計３ｎｍ厚とし
た。比較試料として、上層垂直磁化膜と金属膜を省いた
試料、及び金属膜を省いた以外は実施例と同様の垂直磁
気記録媒体を作製した。Instead of the Pt film as the metal film 36, Pd
Film (1 nm), Ir film (1.5 nm), Re film (0.1
nm), a Ru film (1.2 nm), and a Co / Pt multilayer film (3 nm) were formed in the same manner as described above. Here, the Co / Pt multilayer film is formed by alternately using a Co target and a Pt target by 0.5% each.
Six cycles were formed with a thickness of nm each, giving a total thickness of 3 nm. As comparative samples, a sample in which the upper layer perpendicular magnetic film and the metal film were omitted, and a perpendicular magnetic recording medium similar to the example except that the metal film was omitted were produced.
【００４２】上層及び下層垂直磁化膜の磁気特性を測定
した結果、下層垂直磁化膜：Ｍｓ＝３４０ｅｍｕ／ｃ
ｃ，Ｋｕ＝１．５×１０6ｅｒｇ／ｃｃ、上層垂直磁化
膜：Ｍｓ＝４２０ｅｍｕ／ｃｃ，Ｋｕ＝３×１０6ｅｒ
ｇ／ｃｃであった。上層垂直磁化膜の表面で測定した結
晶粒の平均粒径は１２ｎｍであり、下層垂直磁化膜の結
晶粒界には２６〜３０ａｔ％のＣｒが平均厚さ１ｎｍの
幅で偏析していることを電子顕微鏡を用いた分析で確認
した。また、第２下地層３３と下層垂直磁化膜３４の格
子定数の差は４％であった。これらの磁気記録媒体の記
録再生特性を実施例２の場合と同様の方法で評価した。
結果を表３に示す。As a result of measuring the magnetic properties of the upper and lower perpendicular magnetic films, the lower perpendicular magnetic film: Ms = 340 emu / c
c, Ku = 1.5 × 10 6 erg / cc, upper perpendicular magnetization film: Ms = 420 emu / cc, Ku = 3 × 10 6 er
g / cc. The average grain size of the crystal grains measured on the surface of the upper perpendicular magnetic film is 12 nm, and 26 to 30 at% of Cr is segregated in the crystal grain boundary of the lower perpendicular magnetic film with an average thickness of 1 nm. It was confirmed by analysis using an electron microscope. The difference in lattice constant between the second underlayer 33 and the lower perpendicular magnetization film 34 was 4%. The recording and reproducing characteristics of these magnetic recording media were evaluated in the same manner as in Example 2.
Table 3 shows the results.
【００４３】[0043]
【表３】 [Table 3]
【００４４】本実施例の磁気記録媒体は、比較例に比べ
てＤ50，Ｓ／Ｎが大幅に改善されており、高密度磁気記
録媒体としてさらに望ましいことがわかった。本実施例
で作製した磁気記録媒体を用いて、再生素子として磁気
トンネル現象を応用した高感度再生ヘッドを用いた２．
５インチの磁気記録再生装置を作製した。面記録密度３
０Ｇｂ／ｉｎ2の条件で、表３に示すようにエラーレー
ト１０-9が確保でき、超高密度記録再生装置として動作
することを確認した。The magnetic recording medium of the present embodiment has significantly improved D 50 and S / N as compared with the comparative example, and it has been found that the magnetic recording medium is more desirable as a high-density magnetic recording medium. 1. Using the magnetic recording medium manufactured in this example, a high-sensitivity read head applying a magnetic tunnel phenomenon was used as a read element.
A 5-inch magnetic recording / reproducing apparatus was manufactured. Surface recording density 3
Under the condition of 0 Gb / in 2 , it was confirmed that an error rate of 10 −9 was secured as shown in Table 3 and that the device operated as an ultra-high density recording / reproducing apparatus.
【００４５】［実施例４］実施例２で試作した垂直磁気
記録媒体の上に、厚さ５ｎｍの（Ｃｏ−１０ａｔ％Ｃｒ
−３ａｔ％Ｔａ）／（Ｐｔ−４５ａｔ％Ｒｅ）多層膜を
設けた以外は同様にして、図４に示す断面構造を持つ垂
直磁気記録媒体を作製した。ここで（Ｃｏ−１０ａｔ％
Ｃｒ−３ａｔ％Ｔａ）／（Ｐｔ−４５ａｔ％Ｒｅ）多層
膜は、Ｃｏ−Ｃｒ−Ｔａターゲット、及びＰｔ−Ｒｅタ
ーゲットを交互に用いてそれぞれ０．２５ｎｍの厚さず
つ１０サイクル形成し、合計５ｎｍ厚の金属膜を作製し
た。比較例として、金属膜及び下層垂直膜、中間膜を設
けない垂直磁気記録媒体も作製した。実施例２と同様な
記録再生条件で特性比較を行なった結果を、表４に示
す。Example 4 A 5 nm-thick (Co-10 at% Cr) film was placed on the perpendicular magnetic recording medium experimentally produced in Example 2.
A perpendicular magnetic recording medium having a sectional structure shown in FIG. 4 was produced in the same manner except that a multilayer film of (-3 at% Ta) / (Pt-45 at% Re) was provided. Here, (Co-10at%
The Cr-3at% Ta) / (Pt-45at% Re) multilayer film is formed alternately using Co-Cr-Ta targets and Pt-Re targets for 10 cycles each having a thickness of 0.25 nm, for a total of 5 nm. A thick metal film was produced. As a comparative example, a perpendicular magnetic recording medium without a metal film, a lower perpendicular film, and an intermediate film was also manufactured. Table 4 shows the results of comparing the characteristics under the same recording and reproduction conditions as in Example 2.
【００４６】[0046]
【表４】 [Table 4]
【００４７】本発明の垂直磁気記録媒体の方が比較例に
比べ、Ｄ50，Ｓ／Ｎが改善されており、さらに高密度磁
気記録媒体として望ましいことが分かる。面記録密度２
０Ｇｂ／ｉｎ2の条件で、表４に示すようにエラーレー
ト１０-9が確保でき、超高密度記録再生装置として動作
することが分かった。The perpendicular magnetic recording medium of the present invention has improved D 50 and S / N as compared with the comparative example, and it can be seen that it is more desirable as a high-density magnetic recording medium. Surface recording density 2
Under the condition of 0 Gb / in 2 , an error rate of 10 −9 was secured as shown in Table 4, and it was found that the device operates as an ultra-high density recording / reproducing apparatus.
【００４８】［実施例５］実施例３で試作した垂直磁気
記録媒体と巨大磁気抵抗効果（ＧＭＲ）を用いた高感度
再生素子を持つ録再分離ヘッドを用いて磁気記憶装置を
作製した。この磁気記憶装置は、図５（ａ）に概略平面
図を、図５（ｂ）にそのＡＡ′断面図を示すように、磁
気記録媒体駆動部５２により回転駆動される磁気記録媒
体５１、磁気ヘッド駆動部５４により保持されて磁気記
録媒体５１に対して記録および再生を行う磁気ヘッド５
３、磁気ヘッド５３の記録信号および再生信号を処理す
る記録再生信号処理系５５を備える周知の構成の装置で
ある。記録ヘッドのトラック幅０．４ｍｍ，再生用のＧ
ＭＲヘッド素子のトラック幅０．３２ｍｍ、ヘッドと媒
体のスペーシング１５ｎｍとした。信号処理としてＰＲ
５方式を採用し、３０Ｇｂ／ｉｎ2の面記録密度の条件
で装置を動作させたところ、いずれの垂直媒体において
も１０-8以下の誤り率が得られた。[Embodiment 5] A magnetic storage device was manufactured using a perpendicular magnetic recording medium experimentally manufactured in Embodiment 3 and a recording / reproducing separation head having a high-sensitivity reproducing element using the giant magnetoresistance effect (GMR). As shown in a schematic plan view in FIG. 5A and a cross-sectional view along the line AA ′ in FIG. 5B, the magnetic storage device includes a magnetic recording medium 51 that is rotationally driven by a magnetic recording medium driving unit 52. Magnetic head 5 that is held by head drive unit 54 and performs recording and reproduction on magnetic recording medium 51
3. An apparatus having a known configuration including a recording / reproducing signal processing system 55 for processing a recording signal and a reproducing signal of the magnetic head 53. Track width of recording head 0.4 mm, G for reproduction
The track width of the MR head element was 0.32 mm, and the spacing between the head and the medium was 15 nm. PR as signal processing
When the apparatus was operated under the conditions of a surface recording density of 30 Gb / in 2 employing the five methods, an error rate of 10 -8 or less was obtained in any of the perpendicular media.
【００４９】[0049]
【発明の効果】本発明によれば、垂直磁気記録媒体のノ
イズを低減することができ、この結果高いＳ／Ｎ比が得
られるので、磁気ディスク装置の高密度化が可能とな
る、特に１０Ｇｂ／ｉｎ2以上の高密度磁気記録が可能
となり、装置の小型化や大容量化が容易になる。According to the present invention, the noise of the perpendicular magnetic recording medium can be reduced, and as a result, a high S / N ratio can be obtained, so that the density of the magnetic disk drive can be increased, especially 10 Gb. / In 2 or higher density magnetic recording becomes possible, making it easier to reduce the size and capacity of the device.
【図１】本発明による磁気記録媒体の一例の断面図。FIG. 1 is a sectional view of an example of a magnetic recording medium according to the present invention.
【図２】本発明による磁気記録媒体の他の例の断面図。FIG. 2 is a sectional view of another example of the magnetic recording medium according to the present invention.
【図３】本発明による磁気記録媒体の他の例の断面図。FIG. 3 is a sectional view of another example of the magnetic recording medium according to the present invention.
【図４】本発明による磁気記録媒体の他の例の断面図。FIG. 4 is a sectional view of another example of the magnetic recording medium according to the present invention.
【図５】磁気記憶装置の構成図。FIG. 5 is a configuration diagram of a magnetic storage device.
１１…基板、１２…第１下地層、１３…第２下地層、１
４…下層垂直磁化膜、１５…上層垂直磁化膜、１６…保
護膜、２１…基板、２２…第１下地層、２３…第２下地
層、２４…下層垂直磁化膜、２５…中間層、２６…上層
垂直磁化膜、２７…保護膜、３１…基板、３２…第１下
地層、３３…第２下地層、３４…下層垂直磁化膜、３５
…上層垂直磁化膜、３６…金属膜、３７…保護膜、４１
…基板、４２…第１下地層、４３…第２下地層、４４…
下層垂直磁化膜、４５…中間層、４６…上層垂直磁化
膜、４７…金属膜、４８…保護膜、５１…磁気記録媒
体、５２…磁気記録媒体駆動部、５３…磁気ヘッド、５
４…磁気ヘッド駆動部、５５…信号処理部11 ... substrate, 12 ... first underlayer, 13 ... second underlayer, 1
4 ... Lower perpendicular magnetization film, 15 ... Upper perpendicular magnetization film, 16 ... Protective film, 21 ... Substrate, 22 ... First underlayer, 23 ... Second underlayer, 24 ... Lower perpendicular magnetization film, 25 ... Intermediate layer, 26 ... Upper perpendicular magnetic film, 27 ... Protective film, 31 ... Substrate, 32 ... First underlayer, 33 ... Second underlayer, 34 ... Lower perpendicular magnetic film, 35
... upper perpendicular magnetization film, 36 ... metal film, 37 ... protective film, 41
... substrate, 42 ... first underlayer, 43 ... second underlayer, 44 ...
Lower perpendicular magnetization film, 45 middle layer, 46 upper perpendicular magnetization film, 47 metal film, 48 protective film, 51 magnetic recording medium, 52 magnetic recording medium drive unit, 53 magnetic head, 5
4: magnetic head drive unit, 55: signal processing unit
フロントページの続き (72)発明者 吉田 和悦 東京都国分寺市東恋ヶ窪一丁目280番地 株式会社日立製作所中央研究所内 (72)発明者 本多 幸雄 東京都国分寺市東恋ヶ窪一丁目280番地 株式会社日立製作所中央研究所内Continued on the front page (72) Inventor Kazuyoshi Yoshida 1-280 Higashi-Koigabo, Kokubunji-shi, Tokyo Inside Hitachi, Ltd. Central Research Laboratory (72) Inventor Yukio Honda 1-280 Higashi-Koigabo, Kokubunji-shi, Tokyo Hitachi, Ltd. Inside
Claims (9)
垂直磁化膜を備える垂直磁気記録媒体において、 前記下地層は、六方稠密構造もしくは非晶質構造を持つ
材料からなり前記基板と接する第１下地層と、六方稠密
構造を持ち優先成長方位が［０００１］であってその上
に形成される垂直磁化膜と整合成長し得る材料からなる
第２下地層とからなり、 前記垂直磁化膜は前記第２下地層に接する下層垂直磁化
膜と上層垂直磁化膜とを含み、前記下層及び上層の垂直
磁化膜はＣｏ合金多結晶膜であって、前記上層垂直磁化
膜は前記下層垂直磁化膜より非磁性元素の総添加元素濃
度が低く、かつ飽和磁化（Ｍｓ）及び磁気異方性エネル
ギー（Ｋｕ）が大きく、 前記第２下地層から前記上層垂直磁化膜まで連続的に整
合成長が実現されており、前記垂直磁化膜の総厚が５ｎ
ｍ以上７０ｎｍ以下であり、前記上層垂直磁化膜の表面
側で測定した結晶粒の平均粒径が５ｎｍ以上１５ｎｍ以
下であることを特徴とする垂直磁気記録媒体。1. A perpendicular magnetic recording medium comprising a perpendicular magnetic film formed on a nonmagnetic substrate via an underlayer, wherein the underlayer is made of a material having a hexagonal close-packed structure or an amorphous structure, and is in contact with the substrate. A first underlayer and a second underlayer made of a material having a hexagonal close-packed structure, having a preferential growth orientation of [0001], and capable of growing in alignment with a perpendicular magnetization film formed thereon; Includes a lower perpendicular magnetic film in contact with the second underlayer and an upper perpendicular magnetic film, wherein the lower and upper perpendicular magnetic films are Co alloy polycrystalline films, and the upper perpendicular magnetic film is the lower perpendicular magnetic film. The total added element concentration of the non-magnetic element is lower, the saturation magnetization (Ms) and the magnetic anisotropy energy (Ku) are larger, and matching growth is continuously realized from the second underlayer to the upper perpendicular magnetization film. And said The total thickness of the perpendicular magnetization film is 5n
a perpendicular magnetic recording medium, wherein the average grain size of the crystal grains measured on the surface side of the upper perpendicular magnetic film is 5 nm or more and 15 nm or less.
て、前記下層垂直磁化膜と上層垂直磁化膜の間に六方稠
密構造を持つ非磁性もしくはＭｓ＜５０ｅｍｕ／ｃｃの
中間層が設けられており、前記第２下地層から前記上層
垂直磁化膜まで連続的に整合成長されていることを特徴
とする垂直磁気記録媒体。2. The perpendicular magnetic recording medium according to claim 1, wherein a non-magnetic or Ms <50 emu / cc intermediate layer having a hexagonal close-packed structure is provided between the lower perpendicular magnetic film and the upper perpendicular magnetic film. A perpendicular magnetic recording medium characterized by being continuously grown from the second underlayer to the upper perpendicular magnetization film.
体において、前記上層垂直磁化膜の上に厚さ０．１ｎｍ
から５ｎｍの金属膜が形成されており、前記金属膜はＰ
ｔ，Ｐｄ，Ｉｒ，Ｒｅ，Ｒｕもしくはこれらの元素を主
成分とする合金、あるいはＣｏもしくはＣｏ合金とＰ
ｔ，Ｐｄ，Ｉｒ，Ｒｅ，Ｒｕもしくはそれらの元素を主
成分とする合金との積層膜、あるいは稀土類元素を含む
非晶質磁性材料膜であることを特徴とする垂直磁気記録
媒体。3. The perpendicular magnetic recording medium according to claim 1, wherein a thickness of 0.1 nm is formed on said upper perpendicular magnetization film.
A 5 nm metal film is formed, and the metal film is formed of P
t, Pd, Ir, Re, Ru or alloys containing these elements as main components, or Co or a Co alloy and P
A perpendicular magnetic recording medium characterized by being a laminated film of t, Pd, Ir, Re, Ru or an alloy containing these elements as a main component, or an amorphous magnetic material film containing a rare earth element.
媒体において、前記下層垂直磁化膜はその結晶粒界に２
５ａｔ％以上の非磁性元素の偏析層を持つ多結晶膜であ
ることを特徴とする垂直磁気記録媒体。4. The perpendicular magnetic recording medium according to claim 1, wherein said lower perpendicular magnetic film has a crystal grain boundary of 2 mm.
A perpendicular magnetic recording medium comprising a polycrystalline film having a segregation layer of a nonmagnetic element of 5 at% or more.
磁気記録媒体において、前記下層垂直磁化膜の磁気異方
性エネルギーが１×１０6ｅｒｇ／ｃｃ以上２．５×１
０6ｅｒｇ／ｃｃ以下、上層垂直磁化膜の磁気異方性エ
ネルギーが２．５×１０6ｅｒｇ／ｃｃ以上５×１０6ｅ
ｒｇ／ｃｃ以下であることを特徴とする垂直磁気記録媒
体。5. The perpendicular magnetic recording medium according to claim 1, wherein said lower perpendicular magnetic film has a magnetic anisotropy energy of 1 × 10 6 erg / cc or more and 2.5 × 1.
0 6 erg / cc or less, and the magnetic anisotropy energy of the upper perpendicular magnetization film is 2.5 × 10 6 erg / cc or more and 5 × 10 6 e.
rg / cc or less.
磁気記録媒体において、前記第２下地層と前記下層垂直
磁化膜の格子定数の差が５％以下であることを特徴とす
る垂直磁気記録媒体。6. The perpendicular magnetic recording medium according to claim 1, wherein a difference in lattice constant between said second underlayer and said lower perpendicular magnetic film is 5% or less. Perpendicular magnetic recording medium.
磁気記録媒体において、前記下層垂直磁化膜の厚さが前
記上層垂直磁化膜の厚さの２倍以上であることを特徴と
する垂直磁気記録媒体。7. The perpendicular magnetic recording medium according to claim 1, wherein the thickness of said lower perpendicular magnetic film is at least twice the thickness of said upper perpendicular magnetic film. Perpendicular magnetic recording medium.
動する磁気記録媒体駆動手段と、記録部と再生部とを備
える磁気ヘッドと、前記磁気ヘッドを駆動する磁気ヘッ
ド駆動手段と、前記磁気ヘッドの記録再生信号処理手段
とを含む磁気記憶装置において、 前記磁気記録媒体として請求項１〜７のいずれか１項記
載の垂直磁気記録媒体を用い、前記磁気ヘッドの再生部
として磁気抵抗効果素子もしくは巨大磁気抵抗効果素子
を用い、面記録密度１０Ｇｂ／ｉｎ2以上で磁気記録再
生を行なうことを特徴とする磁気記憶装置。8. A magnetic recording medium, a magnetic recording medium driving unit for driving the magnetic recording medium, a magnetic head including a recording unit and a reproducing unit, a magnetic head driving unit for driving the magnetic head, and the magnetic head 8. A magnetic storage device comprising: a read / write signal processing means for a head; wherein the perpendicular magnetic recording medium according to claim 1 is used as the magnetic recording medium, and a magnetoresistive element is used as a reproducing unit of the magnetic head. Alternatively, a magnetic storage device using a giant magnetoresistive element and performing magnetic recording and reproduction at a surface recording density of 10 Gb / in 2 or more.
動する磁気記録媒体駆動手段と、記録部と再生部とを備
える磁気ヘッドと、前記磁気ヘッドを駆動する磁気ヘッ
ド駆動手段と、前記磁気ヘッドの記録再生信号処理手段
とを含む磁気記憶装置において、 前記磁気記録媒体として請求項１〜７のいずれか１項記
載の垂直磁気記録媒体を用い、前記磁気ヘッドの再生部
として磁気トンネル効果を用いた素子を用い、面記録密
度３０Ｇｂ／ｉｎ2以上で磁気記録再生を行なうことを
特徴とする磁気記憶装置。9. A magnetic recording medium, a magnetic recording medium driving unit for driving the magnetic recording medium, a magnetic head including a recording unit and a reproducing unit, a magnetic head driving unit for driving the magnetic head, and the magnetic head A magnetic storage device including a recording / reproducing signal processing means for a head, wherein the perpendicular magnetic recording medium according to any one of claims 1 to 7 is used as the magnetic recording medium, and a magnetic tunnel effect is provided as a reproducing unit of the magnetic head. A magnetic storage device characterized by performing magnetic recording and reproduction at a surface recording density of 30 Gb / in 2 or more using the used element.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP10093334A JP3011918B2 (en) | 1998-04-06 | 1998-04-06 | Perpendicular magnetic recording medium and magnetic storage device |
| US09/285,751 US6183893B1 (en) | 1998-04-06 | 1999-04-05 | Perpendicular magnetic recording medium and magnetic storage apparatus using the same |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP10093334A JP3011918B2 (en) | 1998-04-06 | 1998-04-06 | Perpendicular magnetic recording medium and magnetic storage device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH11296833A true JPH11296833A (en) | 1999-10-29 |
| JP3011918B2 JP3011918B2 (en) | 2000-02-21 |
Family
ID=14079381
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP10093334A Expired - Fee Related JP3011918B2 (en) | 1998-04-06 | 1998-04-06 | Perpendicular magnetic recording medium and magnetic storage device |
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| Country | Link |
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| JP (1) | JP3011918B2 (en) |
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|---|---|---|---|---|
| JP2004111040A (en) * | 2002-09-19 | 2004-04-08 | Samsung Electronics Co Ltd | Perpendicular magnetic recording medium |
| JP2005222675A (en) * | 2004-01-09 | 2005-08-18 | Tohoku Univ | Perpendicular magnetic recording medium |
| JP2005353278A (en) * | 2001-01-03 | 2005-12-22 | Samsung Electronics Co Ltd | Perpendicular magnetic recording medium |
| SG118167A1 (en) * | 2001-12-07 | 2006-01-27 | Fuji Electric Co Ltd | Perpendicular magnetic recording medium and a method for manufacturing the same |
| JP2006155865A (en) * | 2004-10-29 | 2006-06-15 | Ken Takahashi | Perpendicular magnetic recording medium and perpendicular magnetic recording/reproducing device |
| WO2007114401A1 (en) * | 2006-03-31 | 2007-10-11 | Hoya Corporation | Vertical magnetic recording disk and method for manufacturing the same |
| KR100803201B1 (en) * | 2002-07-27 | 2008-02-14 | 삼성전자주식회사 | Perpendicular magnetic recording media |
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