JPS61199233A - Magnetic recording medium - Google Patents

Abstract

PURPOSE:To improve the crystal orientability and magnetic characteristic of a magnetic layer and to increase the number of times of CSS by providing a nonmagnetic underlying layer consisting of one kind among In, Ir, Pd, Ru, Ta and Pt between a nonmagnetic hardened layer and magnetic medium layer. CONSTITUTION:An alumite film is coated as the nonmagnetic hardened layer 2 to about 4mum on a disk-shaped aluminum alloy substrate 1. After the film is finished to a specular surface, the film of one kind among In, Ir, Pd, Ru, Ta and Pt is formed as the nonmagnetic underlying layer 3 thereon to the thickness ranging 50-2,400Angstrom and a thin gamma-Fe2O3 film is formed as the magnetic medium layer 4 thereon. The adverse influence of the nonmagnetic hardened layer 2 is prevented and the crystal orientability and magnetic characteristic of the magnetic layer are improved by providing the nonmagnetic underlying layer 3 consisting of, for example, the In film in the above-mentioned manner. The increase in the number of times of the contact start stop CSS is thus made possible.

Description

【発明の詳細な説明】 〔産業上の利用分野〕 この発明ｒｌＬ、　ｆｃとえばコバルト、コバルト合金
。[Detailed Description of the Invention] [Industrial Application Field] This invention rlL, fc, such as cobalt and cobalt alloys.

鉄、鉄合金、ニッケル、ニッケル台金などの金属強磁性
体よりなる磁性層、あるいは酸化鉄、酸化クロムなどの
金属愼化物強磁性体よりなろ磁性層を肩Ｔる磁気記録媒
体に関するものである。This relates to a magnetic recording medium in which the magnetic layer is made of a metal ferromagnetic material such as iron, iron alloy, nickel, or nickel base metal, or a magnetic layer made of a metal ferromagnetic material such as iron oxide or chromium oxide. .

〔従来の技術〕[Conventional technology]

近年、コンピュータ・システム／ｃｉ？ける磁気ディス
ク等の外部記１惹ｇ、直り重要ヰが増大し、高記録摺度
化に対する要求はますます高まっている。In recent years, computer systems/ci? The importance of external recording and repair of magnetic disks and the like is increasing, and the demand for high recording performance is increasing.

磁気記録装置は記録再生ヘッドおよび磁気ディスクの主
構成部から構成され、磁気ディスクば尚速で回転し記録
再生ヘッドハ蝿気ディスクより微小間隔浮上している。A magnetic recording device is composed of the main components of a recording/reproducing head and a magnetic disk.The magnetic disk rotates at a high speed, and the recording/reproducing head floats a minute distance above the fly disk.

磁気記録装置の高性能化に伴い、この浮上間隔を小さく
ｒるため罠記録再生ヘッドの荷Ｘを小さくｒるとともに
接触始動・停止（コンタクト・スタート・ストップ：Ｃ
ＢＦ３）Ｉ！ヘッド浮揚システムが採用されている。磁
気ディスクｔなわち磁気記録媒体の高記録府度化、高性
能化を図るためには、記録媒体り薄層化、均−一様化、
磁気特性の改良（保磁力、角形比り向上）。As the performance of magnetic recording devices improves, in order to reduce the flying distance, the load X of the trap recording/reproducing head is reduced and contact start/stop (contact start/stop: C
BF3) I! A head flotation system is used. In order to improve the recording density and performance of magnetic disks, that is, magnetic recording media, it is necessary to make the recording medium thinner, more uniform, and more efficient.
Improved magnetic properties (improved coercive force and squareness).

および低浮上量に２ける安定したヘッド浮揚状１憾を確
保しヘッドとディスクの新突（ヘッド・クラッシュ）を
防止ｔろためのディスク表面精度０同上、）耐ヘッドク
ラッシュ性等の向上が必要でめろ。Also, it is necessary to improve head crash resistance, etc. to ensure a stable head flying condition at low flying heights and prevent new head-to-disk collisions (head crashes). Stop it.

それに１＃−い磁性媒体層を支持する基板り品質の同上
が重要となっている。In addition, the quality of the substrate supporting the 1#-thick magnetic medium layer is also important.

高密度記録に適す石基板の条件としては機械的平坦性お
よび表面粗さが良好であり、欠陥が小さくその数も少な
いことが挙げられる。さらに、記録媒体の薄層化に伴い
基板の十分な硬度も必要とされてきた。−ｔなわち、基
板が軟かいと磁気ヘッドが磁気ディスクに接続した際に
陥没など、’）Ｋ形を起こし、磁気ヘッドの安定した浮
揚状態が得られないばかりか、磁気記録４直の信頼性を
表すコンタクトスタートストップ（０８８）回数が小さ
くなるという問題かめる。Conditions for a stone substrate suitable for high-density recording include good mechanical flatness and surface roughness, and a small number of defects. Furthermore, as the recording medium becomes thinner, the substrate needs to have sufficient hardness. -t In other words, if the substrate is soft, when the magnetic head is connected to the magnetic disk, it will cause a K-shape such as a depression, which will not only make it difficult to obtain a stable floating state of the magnetic head, but also make it difficult to achieve reliable 4-speed magnetic recording. The problem is that the number of contact start/stop (088) times that indicate gender is decreasing.

従来、磁気ディスクの基板にはアルミ合金が使われてい
るが２表面硬化や表面積度をだｔため。Traditionally, aluminum alloys have been used for the substrates of magnetic disks, but this is due to the need for surface hardening and surface area.

その上に硬化層を被覆している。この硬化層は研磨性の
良好なＮ１−Ｐめつき膜やアルマイト膜が用いられてき
た（たとえば、戒々公社研究実用化報告第３１巻第９号
１１３１〜１７４４貞、先行技術　脣祇昭５９−８８６
３３号、〜禎昭５９−１１１４６８号８Ａ［′４）。こ
の膜を形成した後２機械加工を行い表面積度をめげ、磁
性媒体ｌ―を形成する０この磁性媒体Ｉ−の磁気特性と
結晶配向性には密接な関係がわり、、結晶配向性はイみ
性媒体層の下地膜の種類忙影響されることがわかってい
る（たとえば、太田ら。A hardened layer is coated thereon. For this hardened layer, an N1-P plated film or an alumite film with good abrasive properties has been used (for example, Kaishu Kosha Research and Practical Report Vol. 31, No. 9, 1131-1744 Tei, Prior Art) -886
No. 33, ~ Sada Sho 59-111468 No. 8A ['4). After forming this film, mechanical processing is performed to reduce the surface area and form a magnetic medium I. There is a close relationship between the magnetic properties and crystal orientation of this magnetic medium I. It is known that the type of underlying film of the medium layer is influenced by the type of substrate (for example, Ota et al.

第８回日本ん６用磁気学会学術講演概要集、　１５ｐＢ
−ｄ（１９ｄ４））。たとえば、γ−Ｆｅ２０３薄膜の
場合はｒｔｔｔｒｕａ向、　　ｃｏおよびＣＯ合金４腺
の場合ｒｔｃ＠配向した場合が磁気特性が良好でめるこ
とがわめ・つている。Summary of the 8th Japan Magnetics Society Academic Lectures, 15pB
-d(19d4)). For example, it is said that magnetic properties are better when the γ-Fe203 thin film is oriented in the rtttrua orientation, and in the case of co and CO alloys, the rtc@ orientation is achieved.

〔発明が解決しようとをる問題点〕[Problem that the invention seeks to solve]

しかし、擁々の硬化層を形成し磁性媒体層を形成ｔ″る
と　ＩＩよとんどの場合望ましい結晶配向性になりに〈
＜、その結果磁化曲線から求められる角形比Ｓ＊が悪化
するなど磁気時性が良くならないという問題点がめった
。However, when a hardened layer is formed and a magnetic medium layer is formed, the desired crystal orientation is achieved in most cases.
As a result, problems such as deterioration of the squareness ratio S* determined from the magnetization curve and failure to improve magnetic time characteristics were encountered.

この発明に上記のような問題点を解決するためになされ
たもって、結晶配向性すなわち磁気特性が良好で０８８
回数が増大する信頼性の高い磁気記録媒体を得ることを
目的とをる。This invention was made to solve the above-mentioned problems, and the crystal orientation, that is, the magnetic properties are good, and the 088
The purpose is to obtain a highly reliable magnetic recording medium that can be used repeatedly.

〔問題点を解決するための手段〕[Means for solving problems]

この発明の磁気記録媒体に、非磁性硬化層と磁性媒体ｆ
−の間にＩｎ、工ｒ、Ｐｄ、Ｒｕ、Ｔａ、およびｐｔの
うちのいずれか１種よりなる非磁性下地層を形成したも
のでめ６゜ 〔作用〕 この発明に係るＩｎ、工ｒ、Ｐｄ、Ｒｕ、Ｔａ、および
ｐｔのうちのいずれρ）１種より成る非磁性下地層の形
成により、非磁性硬化層の悪影響を防止し、磁性媒体ｔ
Ｍの結晶配向性を艮くすることができ、非磁性硬化層の
硬く表噛、ｆＩ＃度の良好な特性？：減することがない
。The magnetic recording medium of the present invention includes a nonmagnetic hardened layer and a magnetic medium f.
- A non-magnetic underlayer made of any one of In, Al, Pd, Ru, Ta, and PT is formed between In, Al, Pd, Ru, Ta, and PT. By forming a non-magnetic underlayer made of one of Pd, Ru, Ta, and pt, the adverse effects of the non-magnetic hardened layer can be prevented and the magnetic medium t
Can the crystal orientation of M be changed, and the non-magnetic hardened layer has a hard surface texture and good fI# properties? : There is no decrease.

〔央ｍｙ＋ｊ］ 以下、この発明の一天雄桝Ｊを図について説明する。第
１図において、（！ｌは非磁性基板でるるアルミニウム
合金基板、（２）は非磁性硬化層、　！３１４ｄＰｔ非
磁性下地層、（４）は磁性媒体層でるる。[Omy + j] Hereinafter, the Ichiten Yumasu J of this invention will be explained with reference to the drawings. In FIG. 1, (!l is a nonmagnetic substrate, an aluminum alloy substrate, (2) is a nonmagnetic hardened layer, !314dPt nonmagnetic underlayer, and (4) is a magnetic medium layer.

以下、具体的実施例によりこの発明をより詳細に説明す
るが、この発明はこれに限定されるものではない〇 実施例 ディスク状アルミニウム合金基板（１）上に非磁性硬化
／ｌ＠１２１としてアルマイト膜を４μｍ被援被覆。ア
ルマイト膜を鏡面仕上げした後、非磁性下地ノ釦３１と
してｐｔ膜を反応スパッタ法により形成した０さらに、
磁性媒体Ｎｌ１ｔ４＋としてγ−Ｐａ２０．．　？ｌ膜
を形成した。Hereinafter, the present invention will be explained in more detail with reference to specific examples, but the present invention is not limited thereto.〇Example: Anodized aluminum as non-magnetic hardening/l@121 was applied on a disk-shaped aluminum alloy substrate (1). The membrane was coated with a 4 μm coating. After mirror-finishing the alumite film, a PT film was formed as a non-magnetic base button 31 by a reactive sputtering method.
As the magnetic medium Nl1t4+, γ-Pa20. ．． ? 1 film was formed.

Ｐｔｇの膜厚を変えた試料を作製し１種々の測定を行い
、結果を表にまとめたｏ＝Ｍ晶配面配向性いて框、Ｘ線
回折法により測定し、　　ｒ　Ｆｅ２０３（スピネル型
ＬＤｚｚｚ方向のピーク１　（２２２）と３１１方向の
ピーク１（３１１）の比によって表現した。角形比Ｓ＊
は磁化曲線より求めた０ さらに、非磁性下地層の膜厚と各特性１＋１の変化を、
非磁性下地層がｐｔの場合の例ｆｊ！：４２図に。Samples with different Ptg film thicknesses were prepared and various measurements were performed, and the results are summarized in the table below. It is expressed by the ratio of peak 1 (222) in the direction to peak 1 (311) in the 311 direction.Square ratio S*
is 0 obtained from the magnetization curve.Furthermore, the change in the thickness of the non-magnetic underlayer and each characteristic 1+1 is
Example when the non-magnetic underlayer is PT fj! : On figure 42.

非磁性下地層がＩｎの場合の例を第３図にそれぞれ示す
。図中９曲線１１はＩ（２２２）／１（３１１）の変化
。An example in which the nonmagnetic underlayer is made of In is shown in FIG. In the figure, curve 11 represents the change in I(222)/1(311).

曲線１２はＳ＊の変化１曲線１３はａｓｓ回数、Ｏ比り
変化を表す。A curve 12 represents a change in S*, and a curve 13 represents a change in the number of assaults compared to O.

庄）Ｐｔｄ厚が０λ（形成しない）の時のＣ８Ｃ８５ｌ
数を１として比で表した。Sho) C8C85l when Ptd thickness is 0λ (not formed)
Expressed as a ratio, with the number being 1.

表および４２図より明らかなように、　ｐｔの膜厚が５
０λを越えると、結晶配向性およびＳ＊の値が向上して
い〈〇一方、　　Ｐｔの膜厚が２４００１を越え３００
０＾以上になると、　　ａＳＳｌ数の悪化がみられた。As is clear from the table and Figure 42, the film thickness of pt is 5
When it exceeds 0λ, the crystal orientation and S* value improve.〇On the other hand, when the Pt film thickness exceeds 24001
When the value exceeded 0^, deterioration of the aSSl count was observed.

ｐｔの膜厚が厚すぎると、非磁性硬化層の効果が薄れて
しまい、　　ｃｓｓｌｊ１２１数の悪化につながったと
考えられる。また、　　３０００１以上だと熱膨張係数
の違いからクラックがはいることが多く、　　３０００
λ以上は望ましくない。It is thought that if the PT film thickness was too thick, the effect of the nonmagnetic hardened layer was weakened, leading to a deterioration in the csslj121 number. Also, if it is over 30001, cracks will often occur due to the difference in thermal expansion coefficient.
λ or more is not desirable.

上＝ｅ実施例では、　ｐｔ換の場合について説明したが
、Ｉｎ、工ｒ　、　ＰｅＬ　、　Ｒｕ　、　Ｔａ　　の
場合であっても同様の結果が得られ、上記実施νりと同
様の効果を奏する。In the above example, the case of pt exchange was explained, but similar results can be obtained even in the case of In, E, PeL, Ru, Ta, and the same effect as in the above-mentioned embodiment is achieved.

〔発明の効果〕〔Effect of the invention〕

以上のよう：（、この発明によれば、非磁性基板と、こ
の非両性基板に被覆された非感性硬化層と。As mentioned above: (According to the present invention, a non-magnetic substrate and a non-sensitive hardened layer coated on the non-ampholytic substrate.

この非磁性硬化層に被覆された工ｎ、Ｉｒ、Ｐｄ、Ｒｕ
。This non-magnetic hardened layer is coated with iron, Ir, Pd, Ru.
.

Ｔａ、、＆−よびｐｔ　／）うちのいずれか１種よりな
る非磁性Ｆ地層と、この非磁性下池１−に抜機された磁
性媒体層を備えたので、結晶−向性および磁気％性が同
上し、　　ａｓｓｌ！ｌ！ｌ数が増大し、信頼性の＾い
磁気記録媒体が得られる効果かめる。Since the non-magnetic F layer made of any one of Ta, , &- and pt/) and the magnetic medium layer cut out from this non-magnetic lower pond 1- are provided, the crystal orientation and magnetic % Same as above, assl! l! The effect of increasing the l number and obtaining a highly reliable magnetic recording medium can be seen.

ま次、Ｉｎ、■ｒ、Ｐｄ、Ｒｕ、Ｔａ、およびｐｔのう
ちＤいずれか１種よりなる非磁性下地層の厚さを５０〜
２４００＾の範囲にすると、一層上述の効果が増大する
０The thickness of the non-magnetic underlayer made of one of In, ■r, Pd, Ru, Ta, and PT is 50~
If the range is 2400^, the above effect will be further increased.

【図面の簡単な説明】[Brief explanation of drawings]

第１図はこの発明の一実施例により得られた磁気記録媒
体を示す断面図でるり、第２図および第３図は非磁性下
地層の膜厚と各特性値の変化を示す特注図でりる。 山・・・非磁性基板、（２）・・・非磁性硬化層、Ｉ３
）・・・ｐｔ非磁性下地層、（４）・・・磁性媒体層。Fig. 1 is a cross-sectional view showing a magnetic recording medium obtained by an embodiment of the present invention, and Figs. 2 and 3 are custom-made drawings showing changes in the thickness of the nonmagnetic underlayer and each characteristic value. Rir. Mountain...Nonmagnetic substrate, (2)...Nonmagnetic hardened layer, I3
)...PT nonmagnetic underlayer, (4)...magnetic medium layer.

Claims (2)

【特許請求の範囲】[Claims] （１）非磁性基板と、この非磁性基板に被覆された非磁
性硬化層と、この非磁性硬化層に被覆されたＩｎ、Ｉｒ
、Ｐｄ、Ｒｕ、Ｔａ、およびｐｔのうちのいずれか１種
よりなる非磁性下地層と、この非磁性下地層に被覆され
た磁性媒体層を備えた磁気記録媒体。(1) A nonmagnetic substrate, a nonmagnetic hardened layer coated on the nonmagnetic substrate, and an In, Ir coated nonmagnetic hardened layer.
, Pd, Ru, Ta, and pt, and a magnetic medium layer coated on the nonmagnetic underlayer. （２）Ｉｎ、Ｉｒ、Ｐｄ、Ｒｕ、Ｔａ、およびｐｔのう
ちのいずれか１種より形成された非磁性下地層の膜厚を
５０〜２４００Åの範囲にしたことを特徴とをる特許請
求の範囲第１項記載の磁気記録媒体。(2) The non-magnetic underlayer made of any one of In, Ir, Pd, Ru, Ta, and pt has a thickness in the range of 50 to 2400 Å. The magnetic recording medium according to scope 1.