JPS5965416A - Perpendicular magnetic recording medium - Google Patents
Perpendicular magnetic recording mediumInfo
- Publication number
- JPS5965416A JPS5965416A JP57174870A JP17487082A JPS5965416A JP S5965416 A JPS5965416 A JP S5965416A JP 57174870 A JP57174870 A JP 57174870A JP 17487082 A JP17487082 A JP 17487082A JP S5965416 A JPS5965416 A JP S5965416A
- Authority
- JP
- Japan
- Prior art keywords
- film
- perpendicular magnetic
- magnetic
- recording medium
- magnetic recording
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 239000010955 niobium Substances 0.000 claims abstract description 18
- 229910052758 niobium Inorganic materials 0.000 claims abstract description 12
- 229910052713 technetium Inorganic materials 0.000 claims abstract description 11
- 229910052726 zirconium Inorganic materials 0.000 claims abstract description 10
- QCWXUUIWCKQGHC-UHFFFAOYSA-N Zirconium Chemical compound [Zr] QCWXUUIWCKQGHC-UHFFFAOYSA-N 0.000 claims abstract description 4
- GUCVJGMIXFAOAE-UHFFFAOYSA-N niobium atom Chemical compound [Nb] GUCVJGMIXFAOAE-UHFFFAOYSA-N 0.000 claims abstract description 4
- GKLVYJBZJHMRIY-UHFFFAOYSA-N technetium atom Chemical compound [Tc] GKLVYJBZJHMRIY-UHFFFAOYSA-N 0.000 claims abstract description 4
- 239000011651 chromium Substances 0.000 claims description 15
- 229910052804 chromium Inorganic materials 0.000 claims description 8
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 claims description 6
- 229910017052 cobalt Inorganic materials 0.000 claims description 3
- 239000010941 cobalt Substances 0.000 claims description 3
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 claims description 3
- 239000013078 crystal Substances 0.000 abstract description 9
- 229910000599 Cr alloy Inorganic materials 0.000 abstract description 3
- 229910002056 binary alloy Inorganic materials 0.000 abstract description 2
- 239000010408 film Substances 0.000 description 48
- 239000000758 substrate Substances 0.000 description 25
- 230000005415 magnetization Effects 0.000 description 16
- 238000004544 sputter deposition Methods 0.000 description 14
- 239000008188 pellet Substances 0.000 description 7
- 239000000203 mixture Substances 0.000 description 6
- 239000004642 Polyimide Substances 0.000 description 5
- 238000005566 electron beam evaporation Methods 0.000 description 5
- 229920001721 polyimide Polymers 0.000 description 5
- 239000010409 thin film Substances 0.000 description 5
- 229920002799 BoPET Polymers 0.000 description 4
- 239000005041 Mylar™ Substances 0.000 description 4
- 229910045601 alloy Inorganic materials 0.000 description 4
- 239000000956 alloy Substances 0.000 description 4
- 238000010586 diagram Methods 0.000 description 4
- 229910052782 aluminium Inorganic materials 0.000 description 3
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 3
- 230000007423 decrease Effects 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 238000010884 ion-beam technique Methods 0.000 description 3
- 238000001755 magnetron sputter deposition Methods 0.000 description 3
- 238000000034 method Methods 0.000 description 3
- 229920000139 polyethylene terephthalate Polymers 0.000 description 3
- 239000005020 polyethylene terephthalate Substances 0.000 description 3
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 2
- 229910000684 Cobalt-chrome Inorganic materials 0.000 description 2
- WAIPAZQMEIHHTJ-UHFFFAOYSA-N [Cr].[Co] Chemical compound [Cr].[Co] WAIPAZQMEIHHTJ-UHFFFAOYSA-N 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 239000010952 cobalt-chrome Substances 0.000 description 2
- 238000009826 distribution Methods 0.000 description 2
- 230000008020 evaporation Effects 0.000 description 2
- 238000001704 evaporation Methods 0.000 description 2
- 238000002474 experimental method Methods 0.000 description 2
- 239000011521 glass Substances 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 239000012528 membrane Substances 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 229910000889 permalloy Inorganic materials 0.000 description 2
- 230000035699 permeability Effects 0.000 description 2
- 238000007747 plating Methods 0.000 description 2
- -1 polyethylene terephthalate Polymers 0.000 description 2
- 229910002058 ternary alloy Inorganic materials 0.000 description 2
- 229910000859 α-Fe Inorganic materials 0.000 description 2
- 229910019580 Cr Zr Inorganic materials 0.000 description 1
- 229910019817 Cr—Zr Inorganic materials 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 229910052786 argon Inorganic materials 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 238000010894 electron beam technology Methods 0.000 description 1
- 238000005530 etching Methods 0.000 description 1
- 238000011156 evaluation Methods 0.000 description 1
- 230000001747 exhibiting effect Effects 0.000 description 1
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 description 1
- 239000010931 gold Substances 0.000 description 1
- 229910052737 gold Inorganic materials 0.000 description 1
- 238000001659 ion-beam spectroscopy Methods 0.000 description 1
- 239000000696 magnetic material Substances 0.000 description 1
- 238000001552 radio frequency sputter deposition Methods 0.000 description 1
- 238000005096 rolling process Methods 0.000 description 1
- 229920006395 saturated elastomer Polymers 0.000 description 1
- 238000000682 scanning probe acoustic microscopy Methods 0.000 description 1
- 229910000702 sendust Inorganic materials 0.000 description 1
- 238000003860 storage Methods 0.000 description 1
- 238000003852 thin film production method Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
- G11B5/62—Record carriers characterised by the selection of the material
- G11B5/64—Record carriers characterised by the selection of the material comprising only the magnetic material without bonding agent
- G11B5/65—Record carriers characterised by the selection of the material comprising only the magnetic material without bonding agent characterised by its composition
- G11B5/656—Record carriers characterised by the selection of the material comprising only the magnetic material without bonding agent characterised by its composition containing Co
Landscapes
- Magnetic Record Carriers (AREA)
- Thin Magnetic Films (AREA)
Abstract
Description
【発明の詳細な説明】
本発明は、磁気記録材料、より詳しく述べるならば、コ
バルト・クロム垂直磁気記録媒体に関するものである。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to magnetic recording materials, and more particularly to cobalt chromium perpendicular magnetic recording media.
磁気記録媒体は、コンピー−ターの記憶装置に用いられ
一般に記録媒体の長手方向に磁化させている。しかしな
がらこのような磁化方式では記録密度の高密度化に限界
があり、はるかに高密度化が可能となる記録媒体の面に
垂直な方向に磁化する方式が提案されている。そして、
磁性薄膜に対して垂直方向に磁化可能な垂直磁気記録媒
体にはコバルト・クロム（以下Ｏｏ −Ｏｒと略記する
）が使用され、スパッタリングによって基板上に薄膜□
を形成している。垂直記録媒体の作成には、膜面垂直方
向の反磁界に打勝つ垂直磁気異方性を付与することが必
要である。最密六方晶コバルトはＣ軸方向に大きい結晶
磁気異方性を有しているが、磁化が大きいために形状磁
気異方性エネルギーが大きく、垂直磁気異方性膜は得ら
れない。そのため、クロムを添加することにより飽和磁
化を減少させるとともに、最密六方晶のＣ軸を基板垂直
方向に強く配向させることにより垂直磁気異方性膜を作
成することが可能になる。ところが、超高密度磁気記録
を実現させた場合、１つのビットにおける減磁界は、薄
膜時の最大の減磁界４πＭ８（Ｍｓは飽和磁化）より相
当域る筈であり、必ずしも Ｋ ｕ ＞ ２πＭｓｚ
（’Ｋｕは磁化膜の結晶異方性定数である）の条件を満
たす必要はないと考えられる。Magnetic recording media are used in computer storage devices and are generally magnetized in the longitudinal direction of the recording medium. However, such a magnetization method has a limit in increasing the recording density, and a method has been proposed in which magnetization is performed in a direction perpendicular to the surface of the recording medium, which makes it possible to achieve a much higher density. and,
Cobalt chromium (hereinafter abbreviated as Oo-Or) is used for perpendicular magnetic recording media that can be magnetized in the direction perpendicular to a magnetic thin film, and a thin film □ is formed on a substrate by sputtering.
is formed. To create a perpendicular recording medium, it is necessary to provide perpendicular magnetic anisotropy that overcomes the demagnetizing field in the direction perpendicular to the film plane. Close-packed hexagonal cobalt has large magnetocrystalline anisotropy in the C-axis direction, but because of its large magnetization, the shape magnetic anisotropy energy is large, making it impossible to obtain a perpendicular magnetic anisotropic film. Therefore, by adding chromium, it is possible to reduce the saturation magnetization and to strongly orient the C axis of the hexagonal close-packed crystal in the direction perpendicular to the substrate, thereby making it possible to create a perpendicular magnetic anisotropic film. However, when ultra-high-density magnetic recording is realized, the demagnetizing field for one bit should be considerably larger than the maximum demagnetizing field for thin films, 4πM8 (Ms is saturation magnetization), and it is not necessary that K u > 2πMsz
It is considered that it is not necessary to satisfy the condition ('Ku is the crystal anisotropy constant of the magnetized film).
一方、Ｏｏ −’ Ｏｒ垂直磁化膜は、バルクの場合コ
バルトの飽和磁化が、クロム含有量が増えるに従い、直
線的に減少するのに対し、その直線よりやや高い飽和磁
化の減少傾向を示していることから、結晶粒界にクロム
が偏析していることが予想され、最近、膜の断面のオー
ジェ電子分光分析によって実証された。つまり、飽和磁
化を下げ、減磁界を小さくするために、結晶粒中に適度
にクロムが混入することと、結晶粒界にクロムが偏析し
、非磁性ｊ音を形成することによって、磁壁移動による
磁化機構を減少させ、結晶粒間を磁気的に分離させて、
単磁区粒子の磁化回転のみにすることが理想的な垂直磁
気記録媒体と考えられる。On the other hand, in the Oo −'Or perpendicularly magnetized film, the saturation magnetization of cobalt decreases linearly as the chromium content increases in the bulk case, but the saturation magnetization decreases slightly higher than the straight line. Therefore, it is predicted that chromium is segregated at the grain boundaries, and this was recently demonstrated by Auger electron spectroscopy analysis of a cross section of the film. In other words, in order to lower the saturation magnetization and reduce the demagnetizing field, an appropriate amount of chromium is mixed into the crystal grains, and chromium is segregated at the grain boundaries, forming a non-magnetic j-sound. By reducing the magnetization mechanism and magnetically separating grains,
An ideal perpendicular magnetic recording medium is considered to have only the magnetization rotation of single domain grains.
従来のＯｏ −Ｏｒ垂直磁化記録媒体は、膜の垂直異方
性（特にここでは垂直異方性磁界Ｈｋで表わす。）を上
げると垂直方向の保磁力Ｈ’ｃ（１）も上昇しでしまう
。In conventional Oo-Or perpendicular magnetization recording media, when the perpendicular anisotropy of the film (particularly expressed here as perpendicular anisotropy magnetic field Hk) is increased, the perpendicular coercive force H'c(1) also increases. .
４インチＧｏターゲットにＣｒペレットをおいて、１２
５μｍ厚のポリイミドにＲＦマグネトロンスパッタ形成
させた例を以下に記す。Place a Cr pellet on a 4 inch Go target and
An example in which 5 μm thick polyimide was formed by RF magnetron sputtering is described below.
例１ 初期真空度 ３ ×Ｉ Ｆ８ｔｏｒｒ投入電力
ＩＫｖ ７０ｍＡ
時間 １ ｈｏｕｒ
における膜特性は、
例２ 初期真空度 ３．５ ：Ｘ： １０−８ｔｏｒｒ
投入電力 ２Ｋｖ １２７ｍＡ
時間 １０ｒｎｉｎ
における膜特性は、
であった。Example 1 Initial degree of vacuum 3 × I F8 torr Input power IKv 70 mA Time 1 hour The film characteristics are as follows: Example 2 Initial degree of vacuum 3.5 :X: 10-8 torr
The membrane properties at input power of 2Kv 127mA and time of 10rnin were as follows.
これは、投入電力を変えた場合の例であるが、基板加熱
した場合も同様の傾向を示す。つまり、熱が膜形成時Ｃ
Ｊかかることによって、保磁力Ｈａも異方性磁界Ｈｋも
上昇する。ところがこれは、現実に非常に不都合である
。垂直記録媒体は、例２′のように高Ｈｋが当然望まし
いのであるが、Ｈｃ（、Ｌ）が大きくなりすぎると、フ
ェライト、パーマロイ、センダスト、アモルファス軟磁
性体等を用いた磁気ヘッドでは飽和させる為に、ヘッド
に流す電流を非常に大きくしなければならない。たとえ
、飽和記録できても消去が固唾であったり、オーバーラ
イド特性が劣化してしまうという欠点が生じる。一方、
例１のような場合には、書き込み電流及び、オーバライ
ドの特性は改善されるが、垂直磁気記録の本来の垂直異
方性磁界が小であるため、高密度記録における磁化反転
がシャープでなく記録密度特性が悪化してしまう。This is an example when the input power is changed, but the same tendency is shown when the substrate is heated. In other words, the heat is C during film formation.
By applying J, both the coercive force Ha and the anisotropic magnetic field Hk increase. However, this is actually very inconvenient. For perpendicular recording media, it is naturally desirable to have a high Hk as in Example 2', but if Hc (, L) becomes too large, magnetic heads using ferrite, permalloy, sendust, amorphous soft magnetic materials, etc. will be saturated. Therefore, the current flowing through the head must be made extremely large. Even if saturation recording is possible, there are drawbacks such as erasing is difficult and override characteristics are deteriorated. on the other hand,
In a case like Example 1, the write current and override characteristics are improved, but because the original perpendicular anisotropy field of perpendicular magnetic recording is small, the magnetization reversal in high-density recording is not sharp and recording Density characteristics deteriorate.
本発明はかかる点を鑑み、Ｃ，ｏ−Ｃｒ系に更に第三元
素としてジルコニウム、ニオビウム、テクネチウムのう
ち少なくとも一種を添加することによりこれらの難点を
解決したものである。In view of these points, the present invention solves these difficulties by further adding at least one of zirconium, niobium, and technetium as a third element to the C, o-Cr system.
本発明の目的は、結晶粒間を磁気的に分離させ、超高密
度磁気記録媒体を提供することにある。An object of the present invention is to magnetically separate crystal grains and provide an ultra-high density magnetic recording medium.
本発明の他の目的は１００ＫＦＲＰＩ以上の超高密度磁
気記録における出力及び分解能を飛躍的に高めることに
ある。Another object of the present invention is to dramatically increase the output and resolution in ultra-high density magnetic recording of 100 KFRPI or more.
本発明はＯｏ −Ｏｒに更に２０重量％（以下ｗｔ％と
略記す）までのジルコニウム（以下Ｚ ｒと略す）、ニ
オビウム（以下Ｎｂと略す）、テクネチウム（以下ＴＣ
と略す）のうち少なくとも１種を加えることにより明ら
かに効果を発揮する。The present invention further includes up to 20% by weight (hereinafter abbreviated as wt%) of zirconium (hereinafter abbreviated as Zr), niobium (hereinafter abbreviated as Nb), and technetium (hereinafter abbreviated as TC) in addition to Oo-Or.
It is clearly effective to add at least one of the following.
Ｚ−ｒ、Ｎｂ、Ｔｃの添加量が２． Ｏｗｔ％を超える
と膜の結晶性が著しく低下し、膜の垂直磁気異方性が急
激に落ちる。従来０ｏＯｒ２元素では、Ｏｒが１２〜３
０ ｗｔ％の範囲で磁気特性、結晶配向とも良好である
とされていたが、本発明のＺ ｒ 、 Ｎ ｂ 、 Ｔ
ａ、添加によってＣｒ量の下限が広がり二元系の場合よ
りも良い特性を示した。When the amount of Z-r, Nb, and Tc added is 2. When the amount exceeds Owt%, the crystallinity of the film is significantly reduced, and the perpendicular magnetic anisotropy of the film is sharply reduced. In the conventional 0oOr2 element, Or is 12 to 3
It was said that the magnetic properties and crystal orientation were good in the range of 0 wt%, but the present invention's Z r , N b , T
a. The lower limit of the amount of Cr was expanded by addition, and the properties were better than those of the binary system.
第１図に本発明の効果を示す。表中の数字はＣＯ中のＣ
ｒとＺｒ、Ｎｂ、Ｔｃの含有■を重量％で表示した。斜
線部が本発明によっ°Ｃ垂直磁気異方性が改善された領
域で、その他は本発明の効果を示さない領域である。FIG. 1 shows the effects of the present invention. The numbers in the table are C in CO.
The contents of r and Zr, Nb, and Tc are expressed in weight%. The shaded area is the area where the °C perpendicular magnetic anisotropy is improved by the present invention, and the other areas are areas where the effect of the present invention is not exhibited.
具体例をして、ＤＣスパッタ、ＲＦスパッタ。Specific examples include DC sputtering and RF sputtering.
マグネトロンスパッタ、対向ターゲット方式スパッタ、
イオンゼームスバソタ、イオンブレーティング電子ビー
ム蒸着、メッキ等薄膜作製法あるいはポリエチレンテレ
フタラート、ポリイミド、ガラス、アルマイト処理した
アルミ基板等の基板１ａ質にかかわらず、本発明のＺｒ
、Ｎｂ、Ｔｃ添加効果がある。一般に、垂直磁気記録媒
体として、垂直磁気記録層単層の場合とその下に裏うち
層として高透磁率層を設ける場合があるが、本発明は裏
うち高透磁率層の材質、例えばパーマロイ、 Ｃｊ。Magnetron sputtering, facing target sputtering,
The Zr of the present invention can be used regardless of the thin film production method such as ion beam evaporation, ion blating electron beam evaporation, or plating, or the quality of the substrate 1a such as polyethylene terephthalate, polyimide, glass, or alumite-treated aluminum substrate.
, Nb, and Tc have the effect of adding. In general, perpendicular magnetic recording media have a single perpendicular magnetic recording layer and a high magnetic permeability layer is provided thereunder as a backing layer. Cj.
系、Ｆｅ系アモルファス高透磁率薄膜を各種変更しても
なりたつ。Even if various changes are made to the Fe-based amorphous high permeability thin film.
以下、実施例にもとずいて本発明を説明する。Hereinafter, the present invention will be explained based on Examples.
実施例１
ポリイミド基板にＲＦｔ源でＣｏ −Ｃ＊及びＣｏ −
Ｃｒ −Ｚ ｒ垂直磁化膜を形成した。Example 1 Polyimide substrate was coated with Co-C* and Co-
A Cr-Zr perpendicular magnetization film was formed.
ターゲットは、Ｃｏ −１３ｗｔ％Ｏｒ、０ｏ−１’６
ｗｔ％Ｑｒ 、Ｃｏ−２０ｗｔ％Ｃ！ｒと３種類のＣ
ｏ −Ｃ！ ｒ合金ターゲットを用いた。Ｃｏ −Ｏｒ
−、Ｚｒ三元系垂直磁化膜については、ｃｏ−ｃｒ合金
ターゲット上に、５ Ｘ ５ Ｘ １ ｍｍのサイズの
Ｚｒペレットを分布が均一になるように配置して各種の
Ｚｒ量の薄膜を作製した。The target is Co-13wt%Or, 0o-1'6
wt%Qr, Co-20wt%C! r and three types of C
o-C! An r alloy target was used. Co-Or
-, Zr ternary perpendicularly magnetized films were prepared by arranging Zr pellets of 5 x 5 x 1 mm in size on a co-cr alloy target so that the distribution was uniform, and producing thin films with various amounts of Zr. did.
各成分の含有量はＸＭＡにて定量を行った。The content of each component was determined by XMA.
スパッタ条件
スパッタ前にペルジャーのベーキング及び、ポリイミド
基板のガス出しを行った。スパッタ中は基板ホルダーを
水冷した。スパッタ時間ハ、１５分で、膜厚は約０６μ
ｍであった。以下↓こ、作製した膜のロッキングカーブ
の半値幅△θ５ｏと磁気特性を示す。Sputtering conditions Prior to sputtering, Pelger baking was performed and the polyimide substrate was degassed. The substrate holder was water-cooled during sputtering. Sputtering time: 15 minutes, film thickness is approximately 0.6μ
It was m. Below ↓ shows the half width Δθ5o of the rocking curve and the magnetic properties of the fabricated film.
Ｃｏ −１３ｗｔ％Ｃ’ｒターゲット上にＺｒペレット
を置いた場合を第１表に示す。同様に、Ｏｏ−１６ｗｔ
％Ｏｒ 、’Ｏｏ’−２０ｗｔ％Ｑｒターゲットを用い
た場合をそれぞれ第２表、第３表に示す。Table 1 shows the case where Zr pellets were placed on a Co-13wt%C'r target. Similarly, Oo-16wt
%Or and 'Oo'-20wt%Qr targets are shown in Tables 2 and 3, respectively.
第１表 （Ｃ”８７ Ｃｒ１３）＋０Ｏ−ｚＺｒｅ第２
表 （Ｃ０８４Ｃｒｌ）ＩＯＱ−ＺＺｒＺ 、
’第６表 （Ｃ０８０Ｃｒ２０）＋００− ｚＺｒｘ本
データは、それぞれ６回の実験の平均をとったもので、
Ｚｒ量は±１％の誤差をもっている。Table 1 (C”87 Cr13)+0O-zZre 2nd
Table (C084Crl)IOQ-ZZrZ,
'Table 6 (C080Cr20)+00- zZrxThis data is the average of 6 experiments each.
The Zr amount has an error of ±1%.
本データにより、次のことがわがる。This data reveals the following:
ｏＺｒを２０ ｗｔ％以下添加することにより、垂直磁
気異方性が２０％近く上昇する。By adding 20 wt% or less of oZr, the perpendicular magnetic anisotropy increases by nearly 20%.
ｏＣｒ（ｉが増加するにつれ、異方性磁界Ｈｋが最大値
をとるｚｒｙｔが低い方へずれている。As oCr(i increases, zryt, where the anisotropic magnetic field Hk takes the maximum value, shifts toward the lower side.
即ち、Ｏｎ、。。−τＯｒｌ のπの値によりＺｒ添
加の最適量は変わる。That is, On. . The optimum amount of Zr addition changes depending on the value of π of -τOrl.
ｏｚｒを２０ｗｔ％以上添加すると結晶配向性が急に悪
化し、垂直磁気異方性も急激に低くなる。When 20 wt% or more of ozr is added, the crystal orientation deteriorates rapidly and the perpendicular magnetic anisotropy also decreases rapidly.
実施例２゜
電子ビーム蒸発源を三個備え、基板と電子ビーム蒸発源
の間に高周波を印加するコイルを備えたイオンブレーテ
ィング装置によりポリイミドテープにＯｏ −Ｏｒ −
Ｔα３元系メディアを作製した。Example 2 Oo -Or - was applied to a polyimide tape using an ion blating device equipped with three electron beam evaporation sources and a coil that applied high frequency between the substrate and the electron beam evaporation source.
Tα ternary media was produced.
各電子ビーム蒸発源にはそれぞれＣｏ 、 Ｃｊｒ 。Each electron beam evaporation source contains Co and Cjr, respectively.
ＴＣを充填し各電子ビームのパワーをコントロールする
ことにより付着膜の組成を変えることが可能である。成
膜速度は約５ｏｏｏｉ／ＦＩｅｃであ・った。It is possible to change the composition of the deposited film by filling it with TC and controlling the power of each electron beam. The film formation rate was about 5oooi/FIec.
実験はＣＯとＯｒの蒸発源のパワーの比を三段階に変更
して生成膜のＣｏとＣｒの重量比が９０：１０，８５：
１５，８０：２０のものに対してＴＣのパワーを変動さ
せて三種の元素の組成を変更した。いずれの場合におい
てもＴｃの量が１０重量％を越えるとＨｋは急激に低下
した。その様子を第２図に示す。０印はＣＯとＯｒの比
が９０：１０．Δ印はＣＯとＯｒの比が８５＝１５．Ｘ
印はＣｏとＣｒ比が８０：２０である。In the experiment, the power ratio of the CO and Or evaporation sources was changed in three stages, and the weight ratio of Co and Cr in the produced film was 90:10, 85:
The composition of the three elements was changed by varying the TC power for the 15, 80:20 sample. In any case, when the amount of Tc exceeded 10% by weight, Hk decreased rapidly. The situation is shown in Figure 2. Mark 0 indicates that the ratio of CO and Or is 90:10. The Δ mark indicates that the ratio of CO and Or is 85=15. X
The mark indicates a Co:Cr ratio of 80:20.
実施例６
対向ターゲット方式スパッタ装置を用い、ビデオ川テー
プを作製し画像処理を行った。Example 6 A video tape was produced using a facing target sputtering device and subjected to image processing.
第６図に対向ターゲット方式スパッタ装置の概略図を示
す。Ｃ０−Ｃｒ２元系ターゲット１と専用の直流電源（
以下ＤＣ電源と記す）２とそれに対向して設けられたＣ
ｏ −Ｃ！ ｒ ７ Ｎ ｂ ３元系ターゲット３と
専用のＤＣ電源４からなり、この対向したターゲット間
に約６００ガウスの磁界を発生させ、基板５がプラズマ
にさらされないようにペルジャーの外側に電磁石６を備
えた構成である。FIG. 6 shows a schematic diagram of a facing target type sputtering apparatus. C0-Cr binary target 1 and dedicated DC power supply (
(hereinafter referred to as DC power supply) 2 and C provided opposite to it
o-C! r 7 N b Consisting of a ternary target 3 and a dedicated DC power source 4, it generates a magnetic field of about 600 Gauss between the opposing targets, and is equipped with an electromagnet 6 outside the Pelger to prevent the substrate 5 from being exposed to plasma. The configuration is as follows.
基板５は、ロール方式で巻き取れるように設計してあり
、後方の加熱及び水冷可能な基板ホルダー７及びそれと
連動したガイド棒によって上下に可動になっている。The substrate 5 is designed to be rolled up in a roll manner, and is movable up and down by a substrate holder 7 at the rear that can be heated and cooled by water, and a guide rod interlocked with the substrate holder 7.
この対向ターゲット方式スパッタ装置は、それぞれの電
極に電源を独立に設けているため、Ｃ０−０ｒ膜中のＮ
ｂ 、ｕｉを変えるにはそれぞれターゲットに加える
パワーを変えればよく、パワーを変えたことによる膜厚
分布の変動は、基板ホルダー及び基板の上下によって制
御した。This facing target type sputtering equipment has an independent power supply for each electrode, so the N in the C0-0r film is
b and ui can be changed by changing the power applied to the target, and the variation in film thickness distribution due to changing the power was controlled by the substrate holder and the vertical position of the substrate.
第４１：ＡにＮ ｂ ｆｉを変えたときの△θ、。と、
Ｈｋの変化を示す。Ｎｌ）が２０ｗｔ％以下の範囲では
ＨｋがＮｂ添加によって急激に上昇している。ただしＮ
ｂが２０ｗｔ％以上添加されると△θ、。が異常に大と
なり結晶性及びその配向性が悪化したと思われる。41st: Δθ when changing N b fi to A. and,
It shows the change in Hk. In the range where Nl) is 20 wt% or less, Hk rapidly increases due to the addition of Nb. However, N
When 20 wt% or more of b is added, Δθ. It is thought that the crystallinity and its orientation deteriorated due to the abnormally large amount of crystallinity.
第４図は、第２図の傾向と全く同様であり、膜形成装置
及び、基板による差はない。The tendency in FIG. 4 is exactly the same as that in FIG. 2, and there is no difference depending on the film forming apparatus and substrate.
実施例４
カウフマン型イオン源から引き出されたアルゴンイオン
ビームをターゲットに照射するイオンビームスパッタ装
置を用いガラス基板上にＣｏ−０ｒ−Ｚ ｒ ３元系メ
ディアを作製した。Example 4 Co-0r-Zr ternary media was produced on a glass substrate using an ion beam sputtering device that irradiates a target with an argon ion beam extracted from a Kauffman ion source.
Ｏｏ −１’ Ｏｗｔ％Ｃ！ｒ、Ｃｏ−１５ｗｔ％Ｃｒ
。Oo −1' Owt%C! r, Co-15wt%Cr
.
（ｊ ｏ ＝ ２０ ｗｔ％Ｏｒの三種ｑ〕メタ−ゲッ
ト上５鵡角で厚さ１ｗｔｂのＺｒペレットを載せてイオ
ンビームを照射しスパッタした。Ｚｒペレットの個数及
１び配置によりガラ段基板上に付着する。・−０・−Ｚ
ｒの組成が変った。いずれのターゲットを用いた場合
でもＺｒが微量混入することにより結晶配向性及び垂直
異方性磁界が向上するが、Ｚｒの量が２０ ｗｔ％を超
えると結晶配向性及び垂直異方性磁界のいずれも極端に
悪化した。(Three types of q with j o = 20 wt% Or) Zr pellets with a thickness of 1 wtb and 5 square meters were placed on the metal get and ion beam irradiation was performed to sputter them. Depending on the number and arrangement of Zr pellets, Adheres to.・-0・-Z
The composition of r has changed. Regardless of which target is used, the crystal orientation and perpendicular anisotropy magnetic field are improved by mixing a small amount of Zr, but when the amount of Zr exceeds 20 wt%, both the crystal orientation and the perpendicular anisotropy magnetic field are improved. has also deteriorated significantly.
実施例５゜
前記８インチマグネトロンスパッタ装置を用い、記録再
生評価用５インチコロッピーメディアを作製した。本ス
パッタ装置は、３基の８インチタ−ゲントを備えており
、電極１にはＣＯメタ−ゲット上膜組成がＣｏ ６５
Ｚ ｒ、 ５ （重電％表示）となるようにＺｒペレッ
トを置いたもの、′４Ｌ極２にはｃｏ−１６ｗｔ％Ｏｒ
ターゲット、電極６にはＣ。Example 5 Using the 8-inch magnetron sputtering apparatus described above, a 5-inch colloppy medium for recording/reproduction evaluation was produced. This sputtering apparatus is equipped with three 8-inch targets, and the CO metal target film composition on electrode 1 is Co65.
Zr pellets were placed so that Zr, 5 (heavy electric % display) was placed, and co-16wt%Or was placed on '4L pole 2.
C for target and electrode 6.
−１６ｗｔ％Ｏｒターゲット上にＮｂベレットを膜組成
が（” ０８４ Ｃｒ１１５ Ｌ６ Ｎｂ４となるよう
に配置した。基板は、５０μｍ厚ポリエチレンテレフタ
ラートを用いた。一般にＰＥＴとか、マイラといわれて
いるものであり、耐熱性に乏しいため、ＤＣ電源により
膜を形成した。スパッタの順序としては、別々の基板に
Ｃｏ ｇ５ Ｚ ｒ、 ５膜を０３μ所同−条件で形成
後、１つの基板には（１！ ０６４０ ｒ １６膜を０
６μｍ、別の基板には（Ｃ（’８４ （ａｒ、６）ｏ
ａＮｂ４膜を０６μｍ作製した。後でメディアにソリが
ないように反対面にも同一条件で膜を形成した。A Nb pellet was placed on a -16wt%Or target so that the film composition was (084Cr115L6Nb4).The substrate used was 50μm thick polyethylene terephthalate.It is generally called PET or Mylar. However, due to its poor heat resistance, the film was formed using a DC power supply.The sputtering order was as follows: Cog5 Zr, 5 films were formed on separate substrates under the same conditions for 0.3μ, and then on one substrate (1! 0640 r 16 membranes 0
6μm, another substrate has (C('84 (ar, 6)o
An aNb4 film with a thickness of 06 μm was fabricated. Later, a film was formed on the opposite side under the same conditions to prevent warping of the media.
スパッタ条件
第５図に、本実施例によって作製したメディアの構成を
示す。メディアＡは、５０μｍマイラ８の両面に０３μ
ｍ厚のＣ０８５Ｚ ｒ１５アモルファス軟磁性膜９と０
６μｍ厚のＣｊ ｏ ｇ ６ Ｃ！ ｒ Ｈ６垂直磁化
膜１０を形成したものであり、メディアＢは、５０ Ｉ
ｔ ｍ マイラ８の両面に０．３ ／ｊ Ｍ厚のＣｏ８
． Ｚｒ、。Sputtering Conditions FIG. 5 shows the structure of the media produced according to this example. Media A is 03 μm on both sides of 50 μm Mylar 8.
m-thick C085Z r15 amorphous soft magnetic film 9 and 0
6 μm thick Cj o g 6 C! r H6 perpendicular magnetization film 10 is formed, and the media B is 50 I
t m 0.3/j M thick Co8 on both sides of Mylar 8
．． Zr.
７ ％ ／ｌｚファス軟磁軟膜性膜９６μｍ厚の（Ｃｏ
８４Ｃｒｌ ）９６ Ｎｂ４垂直磁化膜１１を形成した
ものである。第４表にそれぞれの膜の特性を示す。7%/lz Fass soft magnetic pia film 96 μm thick (Co
84Crl)96Nb4 perpendicular magnetization film 11 is formed. Table 4 shows the characteristics of each film.
ただし、ＣＯ８４Ｃｒ＋６膜と（ａ ｏ８４ｃ ｒ、、
）ｏ６Ｎｂ。However, CO84Cr+6 film and (a o84c r,,
)o6Nb.
膜は、下ｆｆｉのＣｏＺｒアモルファス膜をエツチング
除去したものの特性である。The film has characteristics obtained by etching away the CoZr amorphous film on the bottom ffi.
以上の様な磁気特性を示す膜から構成されたメディアＡ
とメディアＢを、１３μｍ厚パーマロイ主磁極−補助磁
極タイブヘッドで記録再生したときの記録密度特性を第
６図に示す。Media A composed of a film exhibiting the above magnetic properties
FIG. 6 shows the recording density characteristics when recording and reproducing media B and B using a 13 μm thick permalloy main pole-auxiliary pole type head.
第６図は両対数グラフ上でプロットしである。FIG. 6 is plotted on a log-log graph.
縦軸は相対出力、描軸は記録密度を（ＫＦＲＰ、Ｉ）の
単位で記しである。同図からメディアＢの方がセカンド
ビーク、サードピークの出力がかなり大きくなっている
。このことは、Ｃｏ０ｒ膜にＮｂを添加したＣｏＣｒＮ
ｂ三元系垂直磁化膜が、実用上においても０ｏＯｒ二元
系膜よりも優れており、１００に、ＦＲＰＩ以上の超高
密度磁気記録を十分可能ならしめうる。The vertical axis represents relative output, and the drawing axis represents recording density in units of (KFRP, I). From the figure, the second peak and third peak outputs of media B are considerably larger. This means that CoCrN, which is a Co0r film with Nb added,
The b ternary perpendicular magnetization film is superior to the 0oOr binary film in practical terms, and can sufficiently enable ultra-high density magnetic recording of 100 times higher than FRPI.
実施例６゜
８インチターゲットを有するマグネトロンス／ぐツタ装
置を用い、５インチのアルマイト処理したアルミディス
ク上に、非磁性アモルファスＣＯ５゜Ｔα、。（重置％
）を０５μｍ形成させ、ディスクＣにはＣ０１１４０ｒ
１６を０３μｍ、ディスクＤにゆ（００８４Ｏｒ、６）
ｌ＋６．ＴＣ４を０３μｍ作製した。Example 6 Non-magnetic amorphous CO5°Tα was deposited on a 5-inch anodized aluminum disk using a magnetron/gutter device with an 8-inch target. (overlapping%
) was formed to a thickness of 05 μm, and C01140r was formed on disk C.
16 to 03μm, disk D (0084Or, 6)
l+6. TC4 was fabricated to a thickness of 03 μm.
構成図は、第７図に示した。上記２種ディスクの磁気特
性を第５表に示す。The configuration diagram is shown in FIG. Table 5 shows the magnetic properties of the above two types of disks.
０５μｍ 非磁性アモルファスＣｏ、。Ｔ（＋５゜を下
層に設けたのは、アルマイト処理したディスク表面の粗
さを緩和させることと、その上の００８４”ｒ１６と（
Ｃ０８４Ｃｒ＋６ ）９５ ＴＣ５の磁気特性を上昇さ
せるためである。05μm non-magnetic amorphous Co. The reason why T (+5°) was provided in the lower layer was to reduce the roughness of the alumite-treated disk surface, and to provide 0084"r16 and (
This is to improve the magnetic properties of C084Cr+6)95TC5.
上記２種のディスクを用い、５インチウィンチェスター
ディスクドライブで記録再生を行った。Recording and reproduction were performed using the above two types of discs with a 5-inch Winchester disc drive.
浮上量を小さくするため、標準の３６００ ｒｐｍから
１００Ｏｒｐｍに落とした。浮上隈は、ｏ２μｍ程度で
ある。磁気ヘッドは、標準のＭｎ−Ｚｒ−フェライトで
、ギャップは１μηｌであった。In order to reduce the flying height, the standard speed of 3600 rpm was reduced to 100 Orpm. The floating area is about 02 μm. The magnetic head was a standard Mn-Zr-ferrite with a gap of 1 μηl.
ディスクＣとディスクＤを用いた場合の記録密度特性を
第８図に示すＨ軸は相対出力、横軸は記録密度（単位は
ＫＦＲＰ工）である。Ｔｏを４％添加したディスクＤは
、ディスクＣに較べ、セカンドビーク値で倍の出力を得
ている。FIG. 8 shows the recording density characteristics when using disks C and D. The H axis is the relative output, and the horizontal axis is the recording density (unit: KFRP units). Disk D with 4% To added has twice the output in second peak value compared to disk C.
なお、本発明は前記実施例に制約されない。Note that the present invention is not limited to the above embodiments.
Ｃｏ−０ｒ−Ｚｒ、Ｃｏ−０ｒ−Ｎｂ、（１！ｏ−（１
！ ｒ −Ｔ ｃ等の３元合金を作製しうるスパッタ以
外の他の手段、例えば、電子ビーム蒸着、メッキ、ロー
ル法等でもよい。また、実施例２では対向ターゲット方
式の改良装置を用いた例を挙げたが、Ｃｏ −Ｏｒ −
Ｔ Ｏ３元合金で最良の垂直磁気異方性を有する成分組
成が決定されれば、対向する二個のターゲットともに同
一３元材質を用い、同一の直流もしくは高周波電源を使
用する方式でもよい。また、実施例１及び実施例３は基
板を水冷しているが基板加熱を行なうとＣｏ−０，ｒ２
元金膜は例えばＨｋ−６８００と高くなるがＺｒ、Ｎｂ
、Ｔｃ添加により、Ｈｋ＝７’８００〜８５００と更に
高くなる。Co-0r-Zr, Co-0r-Nb, (1!o-(1
! Other means than sputtering that can produce a ternary alloy such as r-Tc, such as electron beam evaporation, plating, and a roll method, may also be used. In addition, in Example 2, an example was given in which the improved device of the facing target method was used, but Co -Or -
Once the composition of the T 2 O ternary alloy with the best perpendicular magnetic anisotropy is determined, the two opposing targets may be made of the same ternary material and the same direct current or high frequency power source may be used. Furthermore, in Examples 1 and 3, the substrate was water-cooled, but when the substrate was heated, Co-0, r2
The base gold film is high, for example, Hk-6800, but Zr, Nb
, by adding Tc, Hk becomes even higher to 7'800 to 8500.
本発明は、以上説明したように、Ｃ０−Ｃｒ膜にＺｒ
、Ｎｂ 、Ｔｃを２０重量％以下含有させ、ＣｏＣｒ２
元合金における垂直磁気異方性の限界を大きく上回る垂
直磁気記録媒体を作り出し、現在の記録密度特性を大幅
に改善した超高密度磁気記録媒体を作り出すものである
。As explained above, in the present invention, Zr is added to the C0-Cr film.
, Nb, and Tc at 20% by weight or less, and CoCr2
The aim is to create a perpendicular magnetic recording medium that greatly exceeds the limit of perpendicular magnetic anisotropy in the original alloy, and to create an ultra-high-density magnetic recording medium that greatly improves current recording density characteristics.
第１図は本発明の詳細な説明する図である。
第２図は実施例２を説明するためのもので、Ｔｃ添加量
に対する異方性磁界Ｈｋの変化を示したもの。
第！１図及び第４図は、実施例６を説明するためのもの
で、それぞれ装置の構成図、Ｎｂ量に対する膜特性の変
化を示したもの。
第５図、第６図は、実施例５を説明するためのもので、
メディアの構ｒｆｊＪｍ及びそれぞれのメディアの記録
密度特性。
第７図、第８図は、実施例６を説明するだめのもので、
磁気ディスクの構成図及びそれぞれの磁気ディスクの記
録密度特性である。
１・・・０ｏＯｒ合金ターゲット
２・・・直流電源
３・・・Ｃｏ ＣｒＮｂ合金ターゲット４・・・直流電
源
５・・・基板
６・・・電磁石
７・・・基板ホルダー
８・・・マイラ（５０μｍ）
９ ・＝ Ｏｏ Ｚ’： ｒ膜（０６μｍ）１０− Ｏ
ｏ Ｃｒ膜（０６μｔｎ）
１１・＝Ｏｏ’０ｒＮｂ膜（０６μｔｎ）１２・・・ア
ルミディスク（１，９語）１３・・・アルマイト
１ ４− Ｃｏ Ｔ ａ膜（ｏ５ｕ ｍ ）ｉ ５−
Ｏｏ Ｏｒ膜あるいはＣｏ （！ｒＴｃ膜（０３μｍ
）
以 上
第１図
７ｃ （１１／ｌ； ％ ）
Ｎ１１ ｔ どｗｔ −７，）
第５図
第６図
第７図
１１１７ （ｋＦｌ’ＦＩ）
第８図FIG. 1 is a diagram illustrating the present invention in detail. FIG. 2 is for explaining Example 2, and shows the change in the anisotropic magnetic field Hk with respect to the amount of Tc added. No.! 1 and 4 are for explaining Example 6, and show the configuration of the apparatus and the change in film properties with respect to the amount of Nb, respectively. FIG. 5 and FIG. 6 are for explaining Example 5,
Media structure rfjJm and recording density characteristics of each media. FIG. 7 and FIG. 8 are for explaining the sixth embodiment.
1 is a configuration diagram of a magnetic disk and recording density characteristics of each magnetic disk. 1...0oOr alloy target 2...DC power source 3...Co CrNb alloy target 4...DC power source 5...Substrate 6...Electromagnet 7...Substrate holder 8...Mylar (50 μm ) 9 ・= Oo Z': r film (06 μm) 10- O
o Cr film (06μtn) 11・=Oo'0rNb film (06μtn) 12... Aluminum disk (1,9 words) 13... Alumite 1 4- Co Ta film (o5um) i 5-
Oo Or film or Co (!rTc film (03 μm
) Above Figure 1 7c (11/l; % ) N11 t wt -7,) Figure 5 Figure 6 Figure 7 1117 (kFl'FI) Figure 8
Claims (1)
、テクネチウムのうち少なくとも一種を含有することを
特徴とする垂直磁気記録媒体。A perpendicular magnetic recording medium characterized by containing at least one of zirconium, niobium, and technetium in addition to cobalt and chromium.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP57174870A JPS5965416A (en) | 1982-10-05 | 1982-10-05 | Perpendicular magnetic recording medium |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP57174870A JPS5965416A (en) | 1982-10-05 | 1982-10-05 | Perpendicular magnetic recording medium |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS5965416A true JPS5965416A (en) | 1984-04-13 |
| JPH0514406B2 JPH0514406B2 (en) | 1993-02-25 |
Family
ID=15986094
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP57174870A Granted JPS5965416A (en) | 1982-10-05 | 1982-10-05 | Perpendicular magnetic recording medium |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS5965416A (en) |
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS61204836A (en) * | 1985-06-18 | 1986-09-10 | Victor Co Of Japan Ltd | Production of vertical magnetic recording medium |
| JPS61204823A (en) * | 1985-06-18 | 1986-09-10 | Victor Co Of Japan Ltd | Vertical magnetic recording medium |
| JPS61204825A (en) * | 1985-06-18 | 1986-09-10 | Victor Co Of Japan Ltd | Vertical magnetic recording medium |
| JPS61204828A (en) * | 1985-03-07 | 1986-09-10 | Victor Co Of Japan Ltd | Vertical magnetic recording medium |
| JPS61204821A (en) * | 1985-06-18 | 1986-09-10 | Victor Co Of Japan Ltd | Vertical magnetic recording medium |
| JPS61204822A (en) * | 1985-06-18 | 1986-09-10 | Victor Co Of Japan Ltd | Vertical magnetic recording medium |
| JPS61204824A (en) * | 1985-06-18 | 1986-09-10 | Victor Co Of Japan Ltd | Vertical magnetic recording medium |
| US4792486A (en) * | 1985-03-28 | 1988-12-20 | Victor Company Of Japan, Ltd. | Perpendicular magnetic recording medium |
-
1982
- 1982-10-05 JP JP57174870A patent/JPS5965416A/en active Granted
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS61204828A (en) * | 1985-03-07 | 1986-09-10 | Victor Co Of Japan Ltd | Vertical magnetic recording medium |
| US4792486A (en) * | 1985-03-28 | 1988-12-20 | Victor Company Of Japan, Ltd. | Perpendicular magnetic recording medium |
| JPS61204836A (en) * | 1985-06-18 | 1986-09-10 | Victor Co Of Japan Ltd | Production of vertical magnetic recording medium |
| JPS61204823A (en) * | 1985-06-18 | 1986-09-10 | Victor Co Of Japan Ltd | Vertical magnetic recording medium |
| JPS61204825A (en) * | 1985-06-18 | 1986-09-10 | Victor Co Of Japan Ltd | Vertical magnetic recording medium |
| JPS61204821A (en) * | 1985-06-18 | 1986-09-10 | Victor Co Of Japan Ltd | Vertical magnetic recording medium |
| JPS61204822A (en) * | 1985-06-18 | 1986-09-10 | Victor Co Of Japan Ltd | Vertical magnetic recording medium |
| JPS61204824A (en) * | 1985-06-18 | 1986-09-10 | Victor Co Of Japan Ltd | Vertical magnetic recording medium |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0514406B2 (en) | 1993-02-25 |
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