JPS63257916A - Magnetic recording medium - Google Patents
Magnetic recording mediumInfo
- Publication number
- JPS63257916A JPS63257916A JP9084787A JP9084787A JPS63257916A JP S63257916 A JPS63257916 A JP S63257916A JP 9084787 A JP9084787 A JP 9084787A JP 9084787 A JP9084787 A JP 9084787A JP S63257916 A JPS63257916 A JP S63257916A
- Authority
- JP
- Japan
- Prior art keywords
- thin film
- coercive force
- magnetic thin
- film
- thickness
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 230000005291 magnetic effect Effects 0.000 title claims abstract description 87
- 239000000758 substrate Substances 0.000 claims abstract description 11
- 239000010409 thin film Substances 0.000 claims description 57
- 230000007423 decrease Effects 0.000 claims description 6
- 238000013459 approach Methods 0.000 claims description 2
- 230000001681 protective effect Effects 0.000 abstract description 9
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 abstract description 8
- 229910052782 aluminium Inorganic materials 0.000 abstract description 8
- 239000011651 chromium Substances 0.000 abstract description 5
- 239000000463 material Substances 0.000 abstract description 5
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 abstract description 3
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 abstract description 3
- 229910052799 carbon Inorganic materials 0.000 abstract description 3
- 229910052804 chromium Inorganic materials 0.000 abstract description 3
- ZGDWHDKHJKZZIQ-UHFFFAOYSA-N cobalt nickel Chemical compound [Co].[Ni].[Ni].[Ni] ZGDWHDKHJKZZIQ-UHFFFAOYSA-N 0.000 abstract description 3
- 238000005260 corrosion Methods 0.000 abstract description 3
- 230000007797 corrosion Effects 0.000 abstract description 3
- SIBIBHIFKSKVRR-UHFFFAOYSA-N phosphanylidynecobalt Chemical compound [Co]#P SIBIBHIFKSKVRR-UHFFFAOYSA-N 0.000 abstract description 2
- 230000003247 decreasing effect Effects 0.000 abstract 2
- 229910000990 Ni alloy Inorganic materials 0.000 abstract 1
- 229910001096 P alloy Inorganic materials 0.000 abstract 1
- 239000010408 film Substances 0.000 description 13
- 238000000034 method Methods 0.000 description 12
- 238000007740 vapor deposition Methods 0.000 description 8
- 238000004544 sputter deposition Methods 0.000 description 7
- 238000010586 diagram Methods 0.000 description 6
- 238000007747 plating Methods 0.000 description 5
- 239000000956 alloy Substances 0.000 description 3
- 229910045601 alloy Inorganic materials 0.000 description 3
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 2
- 230000001050 lubricating effect Effects 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- PXHVJJICTQNCMI-UHFFFAOYSA-N nickel Substances [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 2
- 229910052760 oxygen Inorganic materials 0.000 description 2
- 239000001301 oxygen Substances 0.000 description 2
- 238000004458 analytical method Methods 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 238000004364 calculation method Methods 0.000 description 1
- 238000000151 deposition Methods 0.000 description 1
- 230000008021 deposition Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
Landscapes
- Magnetic Record Carriers (AREA)
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は、磁気記憶装置に関し、特に、磁気ディスク装
置及びフロッピーディスク装置に使用される磁気記録媒
体に関するものである。DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a magnetic storage device, and particularly to a magnetic recording medium used in a magnetic disk device and a floppy disk device.
磁気記憶装置の高記録密度化に伴ない、磁気記録媒体の
高保磁力が必要となり、それに対撚するためにメッキ法
、蒸着法、スパッタ法等で磁性薄膜を形成する磁気記録
媒体が検討されている。第４図は、従来のメッキ法、蒸
着法、スパッタ法等による磁気ディスク装置用の磁気記
録媒体の断面図である。第４図において、磁性薄膜記録
媒体１は、アルミニウム素材からなるアルミ基板２上に
、下地膜３、磁性薄膜４．保護膜５をメッキ法、蒸着法
、スパッタリング法等により順次形成している。下地膜
３は１通常磁性薄膜４の耐食性及び強度向上等のために
クロム（Ｃｒ）膜が使用されているが、磁性薄膜４の組
成によって下地膜３の材質も変わって来る。前記の場合
には、磁性薄膜４の組成は、コバルト−ニッケル（Ｃｏ
−Ｎｉ）系合金である。また、保護膜５は、磁性薄膜４
の耐食性及びヘッド６との耐摺動特性を向上させるため
に潤滑性の材質、例えばカーボン（Ｃ）を使用している
。このような磁性薄膜記録媒体１は、保磁力ＨＣが高く
、また、その特徴を生かすためにも、ヘッド６と磁性薄
膜記録媒体１の表面までのスペーシング量ａを約０．２
μｍ位と小さくシ、かつ。As the recording density of magnetic storage devices increases, magnetic recording media need to have high coercive force, and magnetic recording media that form magnetic thin films using plating, vapor deposition, sputtering, etc. are being considered to counter twist. There is. FIG. 4 is a cross-sectional view of a magnetic recording medium for a magnetic disk device using a conventional plating method, vapor deposition method, sputtering method, or the like. In FIG. 4, a magnetic thin film recording medium 1 is constructed of an aluminum substrate 2 made of an aluminum material, a base film 3, a magnetic thin film 4. The protective film 5 is sequentially formed by a plating method, a vapor deposition method, a sputtering method, or the like. The base film 3 is usually a chromium (Cr) film to improve the corrosion resistance and strength of the magnetic thin film 4, but the material of the base film 3 varies depending on the composition of the magnetic thin film 4. In the above case, the composition of the magnetic thin film 4 is cobalt-nickel (Co
-Ni) based alloy. Further, the protective film 5 is a magnetic thin film 4
A lubricating material such as carbon (C) is used to improve the corrosion resistance of the head 6 and the sliding resistance with respect to the head 6. Such a magnetic thin film recording medium 1 has a high coercive force HC, and in order to take advantage of this feature, the spacing amount a between the head 6 and the surface of the magnetic thin film recording medium 1 is set to approximately 0.2.
It is as small as μm.
保護ＷＡ５の厚みｂは約０．０５μｍ、磁性薄膜４の厚
みＣは約０．０５〜０．１μｍ程度となっている。なお
、この種の磁性薄膜記録媒体１に関連するものについて
は、例えば１日本応用磁気学会誌、Ｖｏ １．ｌ Ｏ，
Ｎｏ、１（１９８６）の第７頁から第９頁において論じ
られている。The thickness b of the protection WA5 is approximately 0.05 μm, and the thickness C of the magnetic thin film 4 is approximately 0.05 to 0.1 μm. For information related to this type of magnetic thin film recording medium 1, see, for example, 1 Journal of the Japanese Society of Applied Magnetics, Vol. l O,
No. 1 (1986), pages 7-9.
第５図は、ヘッド６の表面からの距離とヘッド６の水平
方向磁界強度の関係を磁界解析計算により求めた図であ
り、ヘッド表面からの距離ｙ［μｍ］が大きくなるに従
い、ヘッドの水平方向磁界強度Ｈχ［Ｏｅ］が急激に低
下する。高記録密度化には磁性薄膜記録媒体ｌの保磁力
Ｈｅを大きくすることが一策であるが、従来では第４図
及び第５図に示すように、ヘッド６から磁性薄膜４の下
面までの距離ｅにおけるヘット６の水平方向磁界強度Ｈ
χ２以下すなわち、Ｈｅ：ｒａＨχ２になるように磁性
薄膜記録媒体１の保磁力ＨＯを設定する必要があり、保
磁力Ｈｅを余り大きくすることはできない。FIG. 5 shows the relationship between the distance from the surface of the head 6 and the horizontal magnetic field strength of the head 6, obtained by magnetic field analysis calculation. As the distance y [μm] from the head surface increases, the horizontal direction of the head increases. The directional magnetic field strength Hχ [Oe] decreases rapidly. One way to increase the recording density is to increase the coercive force He of the magnetic thin film recording medium l, but conventionally, as shown in FIGS. Horizontal magnetic field strength H of head 6 at distance e
It is necessary to set the coercive force HO of the magnetic thin film recording medium 1 so that it is less than χ2, that is, He:raHχ2, and the coercive force He cannot be made too large.
また、ヘッド６から磁性薄膜４の下面までの距ｓＩｅを
小さくするには、磁性薄膜４の厚みＣを薄くすることも
できるが、その場合には、再生出力が低下することにな
る。また、ヘッド６と磁性薄膜記録媒体１の表面までの
スペーシング量ａ及び保護膜５の厚みｂを小さくするこ
ともできるが。Further, in order to reduce the distance sIe from the head 6 to the lower surface of the magnetic thin film 4, the thickness C of the magnetic thin film 4 can be reduced, but in that case, the reproduction output will be reduced. Furthermore, the spacing amount a between the head 6 and the surface of the magnetic thin film recording medium 1 and the thickness b of the protective film 5 can also be reduced.
この場合には、ヘッド６と磁性薄膜記録媒体１との摺動
特性の信頼性を大幅に低下させることになる。In this case, the reliability of the sliding characteristics between the head 6 and the magnetic thin film recording medium 1 will be significantly reduced.
しかしながら、上記従来技術では、磁性薄膜記録媒体ｌ
の高保磁力の特徴を充分反映させるための配Ｉ＃がされ
ておらず、高記録密度化に対して。However, in the above conventional technology, the magnetic thin film recording medium l
The arrangement I# is not designed to fully reflect the characteristics of high coercive force of the magnetic disk, and this is necessary for increasing the recording density.
保磁力を余り大きくできず、また、保磁力を大きくしよ
うとした場合には、再生出力の低下や、ヘッド６と磁性
薄膜記録媒体１との摺動特性の信頼性を低下させるとい
う問題があった。If the coercive force cannot be increased too much, and if an attempt is made to increase the coercive force, there are problems such as a decrease in reproduction output and a decrease in the reliability of the sliding characteristics between the head 6 and the magnetic thin film recording medium 1. Ta.
本発明は、前記問題点を解決するためになされたもので
ある。The present invention has been made to solve the above problems.
本発明の目的は、磁性薄膜の厚み及びスペーシング量と
保護膜の厚みを薄くすることなく、高記録密度化を達成
することができる磁性薄膜記録媒体を提供することにあ
る。An object of the present invention is to provide a magnetic thin film recording medium that can achieve high recording density without reducing the thickness and spacing of the magnetic thin film and the thickness of the protective film.
本発明の前記ならびにその他の目的と新規な特徴は１本
明Ｉ書の記述及び添付図面によって明らかになるであろ
う。The above and other objects and novel features of the present invention will become clear from the description of this specification and the accompanying drawings.
本願において開示される発明のうち１代表的なものの概
要を簡単に説明すれば、下記のとおりである。A brief overview of one typical invention disclosed in this application is as follows.
すなわち、磁性薄膜を有する磁気記録媒体において、前
記磁性薄膜をその厚さ方向の保磁力が前記基板に近づく
程小さくなるように構成されたものである。That is, in a magnetic recording medium having a magnetic thin film, the coercive force in the thickness direction of the magnetic thin film decreases as it approaches the substrate.
前記手段によれば、磁気記憶装置において、記のために
は、ヘッドの水平方向磁界強度Ｈχより性薄膜の保磁力
Ｈｅを厚み方向に変化させることにより１重ね書きによ
るＳ／Ｎ比を低下させることなく、磁性薄膜の保磁力Ｈ
ｅを高くすることができる。According to the above means, in the magnetic storage device, the S/N ratio due to one overwrite is reduced by changing the coercive force He of the thin film in the thickness direction from the horizontal magnetic field strength Hχ of the head. The coercive force H of the magnetic thin film is
e can be increased.
以下１本発明の一実施例を１図面を用いて具体的に説明
する。An embodiment of the present invention will be specifically described below with reference to one drawing.
なお、実施例を説明するための全回において。In addition, in all the times for explaining the example.
同一機能を有するものは同一符号を付け、その繰り返し
の説明は省略する。Components having the same function are given the same reference numerals, and repeated explanations thereof will be omitted.
第１図は、本発明の一実施例の磁気記録媒体の概略構成
及び磁性薄膜厚に対する保磁力との関係を説明するため
の説明図である。FIG. 1 is an explanatory diagram for explaining the schematic structure of a magnetic recording medium according to an embodiment of the present invention and the relationship between coercive force and magnetic thin film thickness.
第１図において、磁性薄膜記録媒体ｌは、アルミニウム
素材からなるアルミ基板２上に、コバルト−リン（Ｃｏ
−Ｐ）系合金及びクロム（Ｃｒ）の下地膜３をメッキ
法、蒸着法、スパッタリング法等により形成し、次に、
コバルト−ニッケル（Ｃ。In FIG. 1, a magnetic thin film recording medium 1 is made of cobalt-phosphorus (Co) on an aluminum substrate 2 made of an aluminum material.
-P) based alloy and chromium (Cr) base film 3 is formed by a plating method, vapor deposition method, sputtering method, etc., and then,
Cobalt-nickel (C.
、、＝Ｎｉ）系合金からなる磁性薄膜４を蒸着法または
スパッタリング法により０．０５μｍ〜０．１μｍの厚
みで形成し、更に磁性薄膜４の上部には磁性薄膜４の耐
食性及びヘッド６との耐摺動特性を向上させるために潤
滑性のカーボン（Ｃ）を蒸着法またはスパッタリング法
により約０．０５μｍの厚みで形成している。この場合
、磁性薄膜４の保磁力Ｈｅは、磁性薄膜４の厚み方向に
よって変化させである。すなわち、アルミ基板２側の磁
性薄膜４の下面部の保磁力Ｈｃ ２及び磁性薄膜記録媒
体１の表面側の磁性薄１１Ａ４の上面部の保磁力Ｈｃｌ
は、Ｈｃｓ ＞ＨＣ２の関係を有し、かつ、第５図に示
すヘッド６の表面からの距離ｙに対するヘッド６の水平
方向磁界強度Ｈχよりも小さくなるようにしである（Ｈ
ｅ≦Ｈχ）。例えば、ヘッド６の表面からの距離ｙがｅ
の時はＨｃ２≦Ｈχ２、ｄの時はＨｅ ｒ≦Ｈχ１であ
る。A magnetic thin film 4 made of a Ni)-based alloy is formed with a thickness of 0.05 μm to 0.1 μm by vapor deposition or sputtering. In order to improve the sliding properties, lubricating carbon (C) is formed to a thickness of about 0.05 μm by vapor deposition or sputtering. In this case, the coercive force He of the magnetic thin film 4 is changed depending on the thickness direction of the magnetic thin film 4. That is, the coercive force Hc 2 of the lower surface of the magnetic thin film 4 on the aluminum substrate 2 side and the coercive force Hcl of the upper surface of the magnetic thin film 11A4 on the front side of the magnetic thin film recording medium 1
has the relationship Hcs > HC2, and is set to be smaller than the horizontal magnetic field strength Hχ of the head 6 with respect to the distance y from the surface of the head 6 shown in FIG.
e≦Hχ). For example, if the distance y from the surface of the head 6 is e
When d, Hc2≦Hχ2, and when d, Her≦Hχ1.
また、磁性薄膜４の保磁力Ｈｅを厚み方向に変化させる
ことは、斜め蒸着法によりできる。第２図は、斜め蒸着
法における入射角θと保磁力Ｈｅとの関係を表わす図で
あるが、入射角θを大きくすることにより保磁力を高く
することができる。Further, the coercive force He of the magnetic thin film 4 can be changed in the thickness direction by an oblique vapor deposition method. FIG. 2 is a diagram showing the relationship between the incident angle θ and the coercive force He in the oblique vapor deposition method, and the coercive force can be increased by increasing the incident angle θ.
すなわち、蒸着時間の経過と共に傾斜角θを叙々に大き
くしてゆくことにより、容易に磁性薄膜４の保磁力Ｈｅ
を厚み方向に高くしてゆくことができる。また、磁性薄
膜４の保磁力Ｈｅを厚み方向に変化させる他の方法とし
ては、第３図に示すように、酸素流量を磁性薄膜形成時
間経過に伴なって増加させてゆく方法がある。この他に
も、磁性薄膜の保磁力Ｈｅを厚み方向に変化させる方法
は種々あるが、いずれの方法によってもよい。また、メ
ッキ法によって磁性薄膜４を形成する場合においても同
様に、液のＰＨ，液温、電流密度等を磁性４の形成時間
の経過と共に変化させることにより、容易に磁性薄膜４
の保磁力Ｈｅを厚み方向に変化させることは可能である
。いずれの方法も。That is, by gradually increasing the inclination angle θ as the deposition time progresses, the coercive force He of the magnetic thin film 4 can be easily increased.
can be increased in the thickness direction. Another method for changing the coercive force He of the magnetic thin film 4 in the thickness direction is to increase the oxygen flow rate as the magnetic thin film formation time elapses, as shown in FIG. In addition to this, there are various methods for changing the coercive force He of the magnetic thin film in the thickness direction, and any method may be used. Similarly, when forming the magnetic thin film 4 by the plating method, the magnetic thin film 4 can be easily formed by changing the pH, temperature, current density, etc. of the liquid as time passes for forming the magnetic 4.
It is possible to change the coercive force He in the thickness direction. Either way.
磁性薄膜記録媒体ｌの磁性薄膜４の保磁力Ｈｅを厚み方
向に変化させるもの、すなわち下面側は低く、上面側が
高くさせるものであれば、何ら本発明から逸脱するもの
ではない。As long as the coercive force He of the magnetic thin film 4 of the magnetic thin film recording medium 1 is changed in the thickness direction, that is, it is made lower on the lower surface side and higher on the upper surface side, it does not deviate from the present invention.
薄膜の保磁力を厚み方向に変化させるため、磁性薄膜の
厚みを小さくする必要はなく、また、ヘッドと磁性薄膜
記録媒体の表面のスペーシング量及び保護膜の厚みを薄
くせずに磁性薄膜の保磁力を比較的高くすることができ
るので、Ｓ／Ｎ比及び記録密度特性を向上させ、しかも
ヘッドと磁性薄膜記録媒体との摺動特性の信頼性の低減
を防止することができる。Since the coercive force of the thin film changes in the thickness direction, there is no need to reduce the thickness of the magnetic thin film, and the thickness of the magnetic thin film can be changed without reducing the spacing between the head and the surface of the magnetic thin film recording medium and the thickness of the protective film. Since the coercive force can be made relatively high, it is possible to improve the S/N ratio and recording density characteristics, and to prevent a decrease in the reliability of the sliding characteristics between the head and the magnetic thin film recording medium.
第１図は、本発明の一実施例の磁性薄膜記録媒体の概略
構成及び磁性薄膜厚ｌ；対する保磁力との関係を説明す
る説明図。
第２図は、磁性薄膜をスパッタリング法で形成する際の
大斜角と保磁力との関係を表わす図。
第３図は、第２図と同様に酸素流量と保磁力との関係を
表わす図。
第４図は、従来の磁気ディスク装置用の磁気記録媒体の
断面図、
第５図は、ヘッド表面からの距離とヘッドの水平方向磁
界強度を示す図である。
図中、１・・・磁性薄膜記録媒体、２・・・アルミ基板
（非磁性基板）、３・・・下地膜、４・・・磁性薄膜、
５・・・保護膜、６・・・ヘッド、ａ・・・ヘッドと記
録媒体表面までのスペーシング量、ｂ・・・保護膜の厚
み、Ｃ・・・磁性薄膜の厚み、ｄ・・・ヘッドと磁性薄
膜上面までの距離、θ・・・ヘッドと磁性薄膜下面まで
の距離である。
第 １ 図
５ ：イ５３ 盲１李Ｅ
６：ヘラＥ゛
第２図 第３区
第４図FIG. 1 is an explanatory diagram illustrating the schematic structure of a magnetic thin film recording medium according to an embodiment of the present invention and the relationship between coercive force and magnetic thin film thickness l; FIG. 2 is a diagram showing the relationship between large oblique angle and coercive force when forming a magnetic thin film by sputtering. FIG. 3 is a diagram showing the relationship between oxygen flow rate and coercive force, similar to FIG. 2. FIG. 4 is a cross-sectional view of a conventional magnetic recording medium for a magnetic disk drive, and FIG. 5 is a diagram showing the distance from the head surface and the horizontal magnetic field strength of the head. In the figure, 1... Magnetic thin film recording medium, 2... Aluminum substrate (non-magnetic substrate), 3... Base film, 4... Magnetic thin film,
5... Protective film, 6... Head, a... Spacing amount between head and recording medium surface, b... Thickness of protective film, C... Thickness of magnetic thin film, d... The distance between the head and the upper surface of the magnetic thin film, θ...the distance between the head and the lower surface of the magnetic thin film. 1 Figure 5: A53 Blind 1 Li E 6: Hera E゛Figure 2 Section 3 Figure 4
Claims (1)
いて、前記磁性薄膜はその厚さ方向の保磁力が前記基板
に近づく程小さくなるように構成されたことを特徴とす
る磁気記録媒体。1. A magnetic recording medium having a magnetic thin film on a non-magnetic substrate, characterized in that the magnetic thin film is configured such that its coercive force in the thickness direction decreases as it approaches the substrate.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP9084787A JPS63257916A (en) | 1987-04-15 | 1987-04-15 | Magnetic recording medium |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP9084787A JPS63257916A (en) | 1987-04-15 | 1987-04-15 | Magnetic recording medium |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS63257916A true JPS63257916A (en) | 1988-10-25 |
Family
ID=14009976
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP9084787A Pending JPS63257916A (en) | 1987-04-15 | 1987-04-15 | Magnetic recording medium |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS63257916A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8064165B2 (en) | 2007-11-16 | 2011-11-22 | Hitachi Global Storage Technologies Netherland B.V. | Electronic information storage apparatus with non-lubricated media |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5862824A (en) * | 1981-10-08 | 1983-04-14 | Nec Corp | Flexible magnetic recording medium |
-
1987
- 1987-04-15 JP JP9084787A patent/JPS63257916A/en active Pending
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5862824A (en) * | 1981-10-08 | 1983-04-14 | Nec Corp | Flexible magnetic recording medium |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8064165B2 (en) | 2007-11-16 | 2011-11-22 | Hitachi Global Storage Technologies Netherland B.V. | Electronic information storage apparatus with non-lubricated media |
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