JPS6379230A - Magnetic recording medium - Google Patents
Magnetic recording mediumInfo
- Publication number
- JPS6379230A JPS6379230A JP22560686A JP22560686A JPS6379230A JP S6379230 A JPS6379230 A JP S6379230A JP 22560686 A JP22560686 A JP 22560686A JP 22560686 A JP22560686 A JP 22560686A JP S6379230 A JPS6379230 A JP S6379230A
- Authority
- JP
- Japan
- Prior art keywords
- layer
- fluorine
- magnetic
- protective layer
- recording medium
- 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 49
- 238000004544 sputter deposition Methods 0.000 claims abstract description 20
- 229910003481 amorphous carbon Inorganic materials 0.000 claims abstract description 9
- 230000005294 ferromagnetic effect Effects 0.000 claims abstract description 7
- PRPAGESBURMWTI-UHFFFAOYSA-N [C].[F] Chemical compound [C].[F] PRPAGESBURMWTI-UHFFFAOYSA-N 0.000 claims description 12
- 239000010409 thin film Substances 0.000 claims description 7
- 229910001092 metal group alloy Inorganic materials 0.000 claims description 4
- 239000010410 layer Substances 0.000 abstract description 26
- 239000011241 protective layer Substances 0.000 abstract description 21
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 abstract description 9
- YCKRFDGAMUMZLT-UHFFFAOYSA-N Fluorine atom Chemical compound [F] YCKRFDGAMUMZLT-UHFFFAOYSA-N 0.000 abstract description 9
- 229910052731 fluorine Inorganic materials 0.000 abstract description 9
- 239000011737 fluorine Substances 0.000 abstract description 9
- 230000007797 corrosion Effects 0.000 abstract description 8
- 238000005260 corrosion Methods 0.000 abstract description 8
- 229910052799 carbon Inorganic materials 0.000 abstract description 7
- 229910045601 alloy Inorganic materials 0.000 abstract description 5
- 239000000956 alloy Substances 0.000 abstract description 5
- 229920000642 polymer Polymers 0.000 abstract description 5
- 239000000758 substrate Substances 0.000 abstract description 5
- 238000007747 plating Methods 0.000 abstract description 4
- 238000007740 vapor deposition Methods 0.000 abstract description 4
- 229910000838 Al alloy Inorganic materials 0.000 abstract description 2
- 230000003247 decreasing effect Effects 0.000 abstract description 2
- 238000007772 electroless plating Methods 0.000 abstract description 2
- 229910002804 graphite Inorganic materials 0.000 abstract description 2
- 239000010439 graphite Substances 0.000 abstract description 2
- OKTJSMMVPCPJKN-NJFSPNSNSA-N Carbon-14 Chemical compound [14C] OKTJSMMVPCPJKN-NJFSPNSNSA-N 0.000 abstract 1
- 229910018104 Ni-P Inorganic materials 0.000 abstract 1
- 229910018536 Ni—P Inorganic materials 0.000 abstract 1
- 239000010408 film Substances 0.000 description 14
- 230000000052 comparative effect Effects 0.000 description 4
- 230000007547 defect Effects 0.000 description 3
- 229910052751 metal Inorganic materials 0.000 description 3
- 239000002184 metal Substances 0.000 description 3
- 238000000034 method Methods 0.000 description 3
- TXEBWPPWSVMYOA-UHFFFAOYSA-N 4-[3-[(1-amino-2-chloroethyl)amino]propyl]-1-[[3-(2-chlorophenyl)phenyl]methyl]-5-hydroxyimidazolidin-2-one Chemical compound NC(CCl)NCCCC1NC(=O)N(Cc2cccc(c2)-c2ccccc2Cl)C1O TXEBWPPWSVMYOA-UHFFFAOYSA-N 0.000 description 2
- 230000007613 environmental effect Effects 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 229910000531 Co alloy Inorganic materials 0.000 description 1
- 239000004809 Teflon Substances 0.000 description 1
- 229920006362 Teflon® Polymers 0.000 description 1
- 238000005299 abrasion Methods 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 230000006866 deterioration Effects 0.000 description 1
- 238000007598 dipping method Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000012212 insulator Substances 0.000 description 1
- 238000010030 laminating Methods 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 239000000314 lubricant Substances 0.000 description 1
- 239000010687 lubricating oil Substances 0.000 description 1
- 238000005461 lubrication Methods 0.000 description 1
- 238000003754 machining Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000005498 polishing Methods 0.000 description 1
- 230000003746 surface roughness Effects 0.000 description 1
Abstract
Description
【発明の詳細な説明】 〔発明の属する技術分野〕 本発明は、基板表面にめっき、スパッタリング。[Detailed description of the invention] [Technical field to which the invention pertains] The present invention involves plating and sputtering on the surface of a substrate.
蒸着などによって形成された金属薄膜磁性層を保護する
ための耐食性および耐磨耗性に優れた表面保護層を有す
る磁気記録媒体に関する。The present invention relates to a magnetic recording medium having a surface protective layer with excellent corrosion resistance and abrasion resistance for protecting a metal thin film magnetic layer formed by vapor deposition or the like.
磁気ディスク装置などに用いられる磁気記録媒体におい
ては、その高記録密度化の要請により、めっき、スパッ
タリング、蒸着などによって形成される磁気特性に優れ
たＣＯ合金などの強磁性金属合金薄膜からなる磁性層が
注目され、検討されている。In magnetic recording media used in magnetic disk devices, etc., due to the demand for higher recording density, a magnetic layer consisting of a thin film of a ferromagnetic metal alloy such as a CO alloy with excellent magnetic properties is formed by plating, sputtering, vapor deposition, etc. is attracting attention and being considered.
ところが、一般にこのような磁性薄膜は金属であるため
に、腐食され易く、磁気ヘッドに対する摩擦係数が大き
くて、磁気ヘッドとの摺動によって磐耗や損傷を受は易
く、磁気特性が劣化するため、薄膜磁性層表面に保護層
を設け、耐食性、耐久性を改善することが行われている
。保護層の膜厚は保護機能の面からは厚い方が望ましい
が、反面、高密度記録を達成するためには、磁気記録装
置において磁気ヘッドと媒体の磁性層との間隙を小さく
する必要があり、磁性層と磁気ヘッドとの間に介在する
保護層の膜厚としては薄い方が望ましいことになり、１
０００Å以下、好ましくは５００Å以下とすることが要
求されている。However, since such magnetic thin films are generally made of metal, they are easily corroded, have a large coefficient of friction against the magnetic head, and are easily abraded and damaged by sliding with the magnetic head, resulting in deterioration of magnetic properties. , a protective layer is provided on the surface of a thin film magnetic layer to improve corrosion resistance and durability. The thicker the protective layer is, the better from the standpoint of protection, but on the other hand, in order to achieve high-density recording, it is necessary to reduce the gap between the magnetic head and the magnetic layer of the medium in a magnetic recording device. , it is desirable that the protective layer interposed between the magnetic layer and the magnetic head be thinner;
000 Å or less, preferably 500 Å or less.
このような表面保護層として、スパッタリングなどによ
り被着されたアモルファス状カーボンく以下ａ−Ｃと略
す）膜が知られている。しかしながら、ａ−Ｃ膜は磁気
ヘッドとの長期間の繰り返しの摺動によって摩擦係数が
増大し、潤滑性能が低下し、また、耐食性も十分ではな
いという難点があった。これを改善するため、ａ−Ｃｇ
Ｏ表面に液状のふっ素糸潤滑剤を浸漬法あるいはスピン
コード法などにより塗布することが試みられているが、
保護層全体の膜厚の制約から、塗布膜厚は５０Å以下に
する必要があり成膜が難しく、しかもａ−Ｃ膜との密着
性が不充分であることから、高信頼性を要求される磁気
記録媒体の保護層としては問題であり、その改善が望ま
れていた。As such a surface protective layer, an amorphous carbon (hereinafter abbreviated as a-C) film deposited by sputtering or the like is known. However, the a-C film has disadvantages in that the coefficient of friction increases due to repeated sliding with the magnetic head over a long period of time, the lubrication performance decreases, and the corrosion resistance is not sufficient. To improve this, a-Cg
Attempts have been made to apply liquid fluorine thread lubricant to the O surface using a dipping method or a spin cord method.
Due to restrictions on the overall thickness of the protective layer, the coating thickness must be 50 Å or less, making it difficult to form a film.Moreover, high reliability is required as the adhesion with the a-C film is insufficient. This is a problem as a protective layer for magnetic recording media, and an improvement has been desired.
本発明は、上述の欠点を除去して、耐磨耗性。 The present invention eliminates the above-mentioned drawbacks and improves wear resistance.
耐食性に優れた表面保護層を有し、特性変動が少なく信
頼性の高い磁気記録媒体を提供することを目的とする。The object of the present invention is to provide a highly reliable magnetic recording medium that has a surface protective layer with excellent corrosion resistance, has little variation in characteristics, and has high reliability.
本発明の目的は、強磁性金属合金薄膜からなる磁性層の
表面にスパッタリングにより被着されたアモルファス状
カーボンとふっ素−カーボン化合物とからなる表面保護
層を備えた磁気記録媒体によって達成される。The object of the present invention is achieved by a magnetic recording medium having a surface protection layer made of amorphous carbon and a fluorine-carbon compound deposited by sputtering on the surface of a magnetic layer made of a ferromagnetic metal alloy thin film.
以下、本発明の実施例について、図面を参照しながら説
明する。Embodiments of the present invention will be described below with reference to the drawings.
実施例１゜
第１図は、本発明による磁気記録媒体の一実施例の層構
成を示す模式的断面図である。第１図において、１１は
アルミニウム合金からなる基板であり、その表面は機械
加工によりうねりの小さい面に仕上げられている。１２
は基板１１の表面に無電解めっきで被着されたＮ１−Ｐ
合金層であり、その表面は機械研暦により表面最大粗さ
０．１μｍ以下に鏡面仕上げされている。その上に、磁
性層１３として、Ｆｅ、Ｃｏ、Ｎｉなどの強磁性金属な
どからなる合金薄膜をめっき、スパッタ、蒸着などで形
成する。この磁性層１３の上に本発明によるａ −Ｃ１
４ａとふっ素−カーボン化合物１４ｂとが混合してなる
表面保護層１４を形成して磁気記録媒体とする。Example 1 FIG. 1 is a schematic cross-sectional view showing the layer structure of an example of a magnetic recording medium according to the present invention. In FIG. 1, reference numeral 11 denotes a substrate made of aluminum alloy, the surface of which is finished by machining into a surface with small undulations. 12
is N1-P deposited on the surface of the substrate 11 by electroless plating.
It is an alloy layer, and its surface is mirror-finished to a maximum surface roughness of 0.1 μm or less by mechanical polishing. Thereon, as the magnetic layer 13, a thin alloy film made of ferromagnetic metal such as Fe, Co, Ni, etc. is formed by plating, sputtering, vapor deposition, or the like. On this magnetic layer 13, a-C1 according to the present invention is applied.
4a and a fluorine-carbon compound 14b are formed to form a surface protective layer 14 to form a magnetic recording medium.
表面保護層１４は、ふっ素糸重合体９例えばテフロン（
商品名、デュポン社製）で一部被覆されたグラファイト
カーボンをターゲットとし、マグネトロン型高周波スパ
ッタリング法で厚さ４００人に形成される。表面保護層
のａ −Ｃ１４ａとふっ素−カーボン化合物１４ｂとの
組成比は被覆するふっ素糸重合体のスパッタリングされ
る有効面積を変化させることにより制御することができ
、例えば、ふっ素−カーボン化合物の含有量を磁性層側
で少なくし、自由表面側にむかって多くしていくという
ように膜厚方向の組成比に所定のプロファイルをもたす
ことも可能である。グラファイト状カーボンターゲット
とふっ素糸重合体ターゲットとを並置し、同時にスパッ
タリングして同様の表面保護層を成膜することも勿論可
能である。The surface protective layer 14 is made of a fluorine thread polymer 9 such as Teflon (
The target is graphite carbon, which is partially coated with DuPont (trade name, manufactured by DuPont), and is formed to a thickness of 400 mm using a magnetron-type high-frequency sputtering method. The composition ratio of a-C14a and the fluorine-carbon compound 14b of the surface protective layer can be controlled by changing the effective sputtered area of the covering fluorine thread polymer, for example, by changing the content of the fluorine-carbon compound. It is also possible to give a predetermined profile to the composition ratio in the film thickness direction, such as decreasing the amount on the magnetic layer side and increasing it toward the free surface side. Of course, it is also possible to arrange a graphite-like carbon target and a fluorine thread polymer target side by side and perform sputtering at the same time to form a similar surface protective layer.
スパッタリングの方法としては、通常の高周波または直
流スパッタリング法、マグネトロン型高周波または直流
スパッタリング法など公知の方法が適用できるが、スパ
ッタリングレイトの点でマグネトロン型の方が有利であ
り、また、ふっ素糸重合体が絶縁物である点で特にマグ
ネトロン型高周波スパッタリング法が適している。As the sputtering method, known methods such as ordinary high frequency or direct current sputtering method, magnetron type high frequency or direct current sputtering method can be applied, but the magnetron type is more advantageous in terms of sputtering rate. The magnetron-type high-frequency sputtering method is particularly suitable because the material is an insulator.
実施例２゜
第２図は、本発明の磁気記録媒体の他の実施例の層構成
を示す模式的断面図であって、１１．１２．１３はそれ
ぞれ実施例１と同様の基’５．Ｎ１−Ｐ層、磁性層であ
る。１４ｃは磁性層１３の表面にスパッタリングにより
平均膜厚３５０人に成膜されたａ−Ｃ膜であり、１４ｄ
はその上に平均膜厚３０人にスパッタリングにより成膜
されたふっ素−カーボン化合物膜であり、１４Ｃと１４
ｄで表面保護層１４が形成されて磁気記録媒体となる。Example 2 FIG. 2 is a schematic cross-sectional view showing the layer structure of another example of the magnetic recording medium of the present invention, in which 11, 12, and 13 are the same groups as in Example 1, respectively. The N1-P layer is a magnetic layer. 14c is an a-C film formed on the surface of the magnetic layer 13 by sputtering to an average thickness of 350 mm, and 14d
is a fluorine-carbon compound film formed by sputtering to an average thickness of 30%.
A surface protective layer 14 is formed in step d to form a magnetic recording medium.
ａ−Ｃ膜１４Ｃとふっ素−カーボン化合物膜１４ｄとは
、並置されたグラファイト状カーボンターゲットとふっ
素糸重合体ターゲットとを次々と連続してスパッタリン
グし積層して成膜される。従って両者の間には明瞭な界
面は存在せず複合膜となっており、その密着性は極めて
強いものである。The a-C film 14C and the fluorine-carbon compound film 14d are formed by successively sputtering and laminating a graphite-like carbon target and a fluorine thread polymer target that are juxtaposed one after another. Therefore, there is no clear interface between the two, forming a composite film, and the adhesion is extremely strong.
比較例
実施例１に準じて磁性層までを形成し、その上に、グラ
ファイト状カーボンターゲットのみを用いてスパッタリ
ングを行い、膜厚３５０人のａ−Ｃ膜を被着させ、この
ａ−Ｃ膜表面にスピンコード法によりふっ素糸液体潤滑
剤９例えばフォンブリン２（商品名、モンテジソン社製
）を膜厚５０Ａに塗布して表面保護層とし磁気記録媒体
を作製した。Comparative Example Up to the magnetic layer was formed according to Example 1, and then sputtering was performed using only a graphite-like carbon target to deposit an a-C film with a thickness of 350 mm. A magnetic recording medium was prepared by applying a fluorine thread liquid lubricant 9 such as Fomblin 2 (trade name, manufactured by Montegisson) to a thickness of 50 Å on the surface by a spin cord method to form a surface protective layer.
以上に述べた実施例１．２および比較例の磁気記録媒体
について、磁気ヘッドとの１耗試験および環境試験を行
った。The magnetic recording media of Example 1.2 and Comparative Example described above were subjected to a wear test with a magnetic head and an environmental test.
磁気ヘッドとの１耗試験は、固定磁気ディスク装置にお
いて一般的に行われている、磁気ヘッドの浮上、接触を
繰り返す、いわゆるｃｓｓ ｃコンタクト・スタート・
ストップ）試験を行い、媒体と磁気ヘッドとの摩擦係数
の変化を測定した。その結果を第１表に示す。A one-time wear test with a magnetic head is a so-called CSS contact start test, which is commonly performed in fixed magnetic disk drives, in which the magnetic head repeatedly floats and makes contact.
A stop) test was conducted to measure changes in the coefficient of friction between the medium and the magnetic head. The results are shown in Table 1.
第１表
第１表に見られるとおり、実施例１．２においてはＣＳ
３１０００回で摩擦係数に僅かな増加はあるものの、
その後の変化は少なり、１０万回まで安定している。一
方、比較例においては、Ｃ３Ｓ２万回までは実施例１，
２と同様であるが、５万回。Table 1 As seen in Table 1, in Example 1.2, CS
Although there is a slight increase in the friction coefficient after 31,000 cycles,
After that, there are few changes, and it remains stable up to 100,000 times. On the other hand, in the comparative example, up to 20,000 times of C3S, Example 1,
Same as 2, but 50,000 times.
１０万回とＣ８Ｓ回数が増すにつれて摩擦係数が大幅に
増大して（る。表面保護層にふっ素−カーボン化合物を
利用すると潤滑性が改善され耐暦耗性の向上に極めて有
効であることが明らかである。As the number of C8S cycles increases to 100,000 cycles, the coefficient of friction increases significantly ().It is clear that using a fluorine-carbon compound in the surface protective layer improves lubricity and is extremely effective in improving wear resistance. It is.
また、温度８０℃、相対湿度８０％の雰囲気中に２０日
間放萱する環境試験を行ったところ、比較例においては
、信号欠陥が２個／面増加したが、実施例１．２におい
ては信号欠陥の増加は認められず、耐食性も向上してい
ることが判る。In addition, when an environmental test was conducted in which the temperature was 80°C and the relative humidity was 80% for 20 days, the number of signal defects increased by 2/side in the comparative example, but the number of signal defects increased by 2/side in the example 1.2. No increase in defects was observed, and it was found that corrosion resistance was improved.
本発明によれば、強磁性金属合金薄膜からなる磁性層の
表面にスパッタリングによりアモルファス状カーボンと
ふっ素−カーボン化合物とからなる表面保護層を形成す
る。かくして、硬度の高いアモルファス状カーボンと潤
滑性、耐食性の優れたふっ素−カーボン化合物それぞれ
の性能が相まって、耐暦粍性、耐食性に優れた表面保護
層を有し、特性変動が少なく信頼性の高い磁気記録媒体
が得られることになる。According to the present invention, a surface protective layer made of amorphous carbon and a fluorine-carbon compound is formed on the surface of a magnetic layer made of a ferromagnetic metal alloy thin film by sputtering. In this way, the performance of amorphous carbon with high hardness and the fluorine-carbon compound with excellent lubricity and corrosion resistance are combined, resulting in a surface protective layer with excellent scratch resistance and corrosion resistance, and high reliability with little variation in properties. A magnetic recording medium will be obtained.
第１図は本発明による磁気記録媒体の一実施例の層構成
、第２図は他の実施例の層構成をそれぞれ示す模式的断
面図である。
１１ 基板、ｌ ２Ｎｉ −Ｐ層、１３ 磁性層、
１４ 表面保護層、１４ａ アモルファス状カーボン
、１４ｂふっ素−カーボン化合物、１４Ｃアモルファス
状カーボン膜、１４ｄ ふっ素−カーボン化合物膜。
第１図
第２図FIG. 1 is a schematic sectional view showing the layer structure of one embodiment of the magnetic recording medium according to the present invention, and FIG. 2 is a schematic cross-sectional view showing the layer structure of another embodiment. 11 substrate, l2Ni-P layer, 13 magnetic layer,
14 Surface protective layer, 14a amorphous carbon, 14b fluorine-carbon compound, 14C amorphous carbon film, 14d fluorine-carbon compound film. Figure 1 Figure 2
Claims (1)
タリングにより被着されたアモルファス状カーボンとふ
っ素−カーボン化合物とからなる表面保護層を備えたこ
とを特徴とする磁気記録媒体。1) A magnetic recording medium comprising a surface protection layer made of amorphous carbon and a fluorine-carbon compound deposited by sputtering on the surface of a magnetic layer made of a ferromagnetic metal alloy thin film.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP22560686A JPS6379230A (en) | 1986-09-24 | 1986-09-24 | Magnetic recording medium |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP22560686A JPS6379230A (en) | 1986-09-24 | 1986-09-24 | Magnetic recording medium |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS6379230A true JPS6379230A (en) | 1988-04-09 |
Family
ID=16831958
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP22560686A Pending JPS6379230A (en) | 1986-09-24 | 1986-09-24 | Magnetic recording medium |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6379230A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS63282914A (en) * | 1987-05-14 | 1988-11-18 | Toshiba Corp | Magnetic recording medium |
| US5275850A (en) * | 1988-04-20 | 1994-01-04 | Hitachi, Ltd. | Process for producing a magnetic disk having a metal containing hard carbon coating by plasma chemical vapor deposition under a negative self bias |
| US5374463A (en) * | 1991-10-22 | 1994-12-20 | International Business Machines Corporation | Magnetic recording disk having a contiguous fullerene film and a protective overcoat |
| EP0735523A2 (en) * | 1995-03-31 | 1996-10-02 | Sony Corporation | Magnetic recording medium and method for producing same |
-
1986
- 1986-09-24 JP JP22560686A patent/JPS6379230A/en active Pending
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS63282914A (en) * | 1987-05-14 | 1988-11-18 | Toshiba Corp | Magnetic recording medium |
| US5275850A (en) * | 1988-04-20 | 1994-01-04 | Hitachi, Ltd. | Process for producing a magnetic disk having a metal containing hard carbon coating by plasma chemical vapor deposition under a negative self bias |
| US5374463A (en) * | 1991-10-22 | 1994-12-20 | International Business Machines Corporation | Magnetic recording disk having a contiguous fullerene film and a protective overcoat |
| EP0735523A2 (en) * | 1995-03-31 | 1996-10-02 | Sony Corporation | Magnetic recording medium and method for producing same |
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