JPH04345916A - Production of protective film of magnetic recording medium - Google Patents
Production of protective film of magnetic recording mediumInfo
- Publication number
- JPH04345916A JPH04345916A JP21942391A JP21942391A JPH04345916A JP H04345916 A JPH04345916 A JP H04345916A JP 21942391 A JP21942391 A JP 21942391A JP 21942391 A JP21942391 A JP 21942391A JP H04345916 A JPH04345916 A JP H04345916A
- Authority
- JP
- Japan
- Prior art keywords
- protective film
- magnetic recording
- recording medium
- manufacturing
- magnetic
- 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.)
- Withdrawn
Links
- 230000001681 protective effect Effects 0.000 title claims abstract description 61
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 23
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 claims abstract description 30
- 239000000758 substrate Substances 0.000 claims abstract description 21
- 229910052786 argon Inorganic materials 0.000 claims abstract description 15
- 238000004544 sputter deposition Methods 0.000 claims abstract description 9
- 238000000034 method Methods 0.000 claims description 26
- 230000005389 magnetism Effects 0.000 claims 1
- 239000010408 film Substances 0.000 description 44
- 239000000314 lubricant Substances 0.000 description 5
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 4
- OFNHPGDEEMZPFG-UHFFFAOYSA-N phosphanylidynenickel Chemical compound [P].[Ni] OFNHPGDEEMZPFG-UHFFFAOYSA-N 0.000 description 4
- 238000007796 conventional method Methods 0.000 description 3
- 238000005498 polishing Methods 0.000 description 3
- MCMNRKCIXSYSNV-UHFFFAOYSA-N Zirconium dioxide Chemical compound O=[Zr]=O MCMNRKCIXSYSNV-UHFFFAOYSA-N 0.000 description 2
- 229910045601 alloy Inorganic materials 0.000 description 2
- 239000000956 alloy Substances 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 239000007789 gas Substances 0.000 description 2
- BHEPBYXIRTUNPN-UHFFFAOYSA-N hydridophosphorus(.) (triplet) Chemical compound [PH] BHEPBYXIRTUNPN-UHFFFAOYSA-N 0.000 description 2
- 238000010297 mechanical methods and process Methods 0.000 description 2
- 229910052759 nickel Inorganic materials 0.000 description 2
- 230000002195 synergetic effect Effects 0.000 description 2
- 239000010409 thin film Substances 0.000 description 2
- 229910018134 Al-Mg Inorganic materials 0.000 description 1
- 229910018467 Al—Mg Inorganic materials 0.000 description 1
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 238000005299 abrasion Methods 0.000 description 1
- 238000013459 approach Methods 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000003754 machining Methods 0.000 description 1
- 238000001755 magnetron sputter deposition Methods 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 238000007747 plating Methods 0.000 description 1
- 238000007788 roughening Methods 0.000 description 1
Landscapes
- Magnetic Record Carriers (AREA)
Abstract
Description
【０００１】0001
【産業上の利用分野】本発明は、情報の磁気的記録に用
いられる磁気ハードディスク等の磁気記録媒体の磁性層
の上に形成される保護膜を製造する磁気記録媒体の保護
膜の製造方法に関する。[Field of Industrial Application] The present invention relates to a method for manufacturing a protective film for a magnetic recording medium, which is formed on a magnetic layer of a magnetic recording medium such as a magnetic hard disk used for magnetic recording of information. .
【０００２】0002
【従来の技術】近年の磁気記録媒体に対する記録密度の
高密度化の要請に対応するために、磁気記録媒体を形成
する磁性層、保護膜等を薄膜形成技術によって形成する
ようにされている。2. Description of the Related Art In order to meet the recent demand for higher recording densities in magnetic recording media, magnetic layers, protective films, etc. that form magnetic recording media are formed using thin film formation techniques.
【０００３】このような磁気記録媒体としては、例えば
Ａｌ−Ｍｇ合金等からなる適宜の厚さの基板上に厚さが
２０μｍ程度のニッケルリン層を形成し、その上面を研
磨等の機械的方法により適度に荒らし、その上に厚さが
０．１μｍ程度のＣｒ下地層を形成し、その上に厚さが
０．０６μｍ程度の磁性層を形成し、その上に厚さが０
．０３μｍ程度の保護膜を形成し、その上に厚さが０．
００３μｍ程度の潤滑剤層を形成することにより構成さ
れている。[0003] Such a magnetic recording medium is produced by forming a nickel phosphorous layer with a thickness of about 20 μm on a substrate of an appropriate thickness made of, for example, an Al-Mg alloy, and then polishing the upper surface by a mechanical method such as polishing. A Cr underlayer with a thickness of about 0.1 μm is formed on it, a magnetic layer with a thickness of about 0.06 μm is formed on it, and a Cr underlayer with a thickness of 0.1 μm is formed on top of it.
．． A protective film with a thickness of about 0.03 μm is formed, and a protective film with a thickness of about 0.03 μm is formed on it.
It is constructed by forming a lubricant layer with a thickness of about 0.003 μm.
【０００４】基板上に形成される各層は、それぞれ公知
の適宜の方法によって形成されるものであるが、Ｃまた
はＺｒＯ２等からなる保護膜はスパッタリング法によっ
て形成されるのもが多い。[0004] Each layer formed on the substrate is formed by a known appropriate method, but a protective film made of C, ZrO2, etc. is often formed by a sputtering method.
【０００５】この保護膜は、情報の記録・再生の度に磁
気記録媒体の表面に対して接離動作を繰返す磁気ヘッド
によって磁性層が損傷されるのを防止するために必要と
されている。This protective film is necessary to prevent the magnetic layer from being damaged by a magnetic head that repeatedly approaches and separates from the surface of the magnetic recording medium each time information is recorded or reproduced.
【０００６】[0006]
【発明が解決しようとする課題】従来、保護膜を製造す
る場合には、スパッタリング法の条件を、例えばＡｒガ
ス圧力が２．５ミリトル程度の真空中で、１００℃程度
の基板温度を条件としていた。[Problems to be Solved by the Invention] Conventionally, when manufacturing a protective film, the conditions of the sputtering method were, for example, in a vacuum with an Ar gas pressure of about 2.5 mTorr and a substrate temperature of about 100°C. there was.
【０００７】そのために、得られた磁気記録媒体すなわ
ち保護膜のＣＳＳ特性が劣り、また振動試験の結果にお
いても磁気記録媒体の表面に傷が発生しているという不
都合があった。[0007] For this reason, the obtained magnetic recording medium, that is, the protective film, had poor CSS characteristics, and the vibration test results also showed that the surface of the magnetic recording medium had scratches.
【０００８】これらの不都合を解消するためには、保護
膜および潤滑剤の膜厚を厚くする必要があるが、そうす
ると電磁変換特性が劣化したり、磁気ヘッドが吸着した
り、コストが高くなるという問題点があった。[0008] In order to eliminate these disadvantages, it is necessary to increase the thickness of the protective film and lubricant, but this will deteriorate the electromagnetic conversion characteristics, cause the magnetic head to stick to it, and increase costs. There was a problem.
【０００９】本発明はこれらの点に鑑みてなされたもの
であり、耐摩耗性に優れた保護膜を製することができ、
磁気記録媒体の製造コストを低減することのできる磁気
記録媒体の保護膜の製造方法を提供することを目的とす
る。The present invention has been made in view of these points, and it is possible to produce a protective film with excellent wear resistance.
It is an object of the present invention to provide a method for manufacturing a protective film for a magnetic recording medium that can reduce the manufacturing cost of the magnetic recording medium.
【００１０】0010
【課題を解決するための手段】前記目的を達成するため
に、請求項１に記載の本発明の磁気記録媒体の保護膜の
製造方法は、磁気記録媒体の磁性層の上にスパッタリン
グ法により保護膜を形成する磁気記録媒体の保護膜の製
造方法において、アルゴン圧を１ミリトル以下にして前
記保護膜を形成することを特徴とする。Means for Solving the Problems In order to achieve the above object, a method for manufacturing a protective film for a magnetic recording medium according to the present invention as set forth in claim 1 provides a method of manufacturing a protective film for a magnetic recording medium by sputtering a protective film on a magnetic layer of a magnetic recording medium. A method of manufacturing a protective film for a magnetic recording medium in which a film is formed is characterized in that the protective film is formed at an argon pressure of 1 mTorr or less.
【００１１】請求項２に記載の本発明の磁気記録媒体の
保護膜の製造方法は、磁気記録媒体の磁性層の上にスパ
ッタリング法により保護膜を形成する磁気記録媒体の保
護膜の製造方法において、基板温度を２００℃以上にし
て前記保護膜を形成することを特徴とする。A method for manufacturing a protective film for a magnetic recording medium according to the present invention according to claim 2 includes forming a protective film on a magnetic layer of a magnetic recording medium by a sputtering method. , the protective film is formed at a substrate temperature of 200° C. or higher.
【００１２】請求項３に記載の本発明の磁気記録媒体の
保護膜の製造方法は、磁気記録媒体の磁性層の上にスパ
ッタリング法により保護膜を形成する磁気記録媒体の保
護膜の製造方法において、アルゴン圧を１ミリトル以下
とするとともに基板温度を２００℃以上にして前記保護
膜を形成することを特徴とする。A method for manufacturing a protective film for a magnetic recording medium according to the present invention according to claim 3 is a method for manufacturing a protective film for a magnetic recording medium, in which a protective film is formed on a magnetic layer of a magnetic recording medium by a sputtering method. , the protective film is formed at an argon pressure of 1 mTorr or less and a substrate temperature of 200° C. or more.
【００１３】[0013]
【作用】請求項１に記載の本発明の磁気記録媒体の保護
膜の製造方法によれば、アルゴン圧を１ミリトル以下に
して保護膜を形成しているために、保護膜が緻密になり
、ＣＳＳ特性が大きく向上して耐摩耗性に優れたものと
なる。According to the method for manufacturing a protective film for a magnetic recording medium according to the present invention as set forth in claim 1, since the protective film is formed at an argon pressure of 1 mTorr or less, the protective film becomes dense. CSS properties are greatly improved and wear resistance is excellent.
【００１４】また、請求項２に記載の本発明方法によれ
ば、基板温度を２００℃以上にして保護膜を形成してい
るために、下地への密着性が良くなり、振動試験の結果
においても傷が発生せず、耐摩耗性の優れたものとなる
。Furthermore, according to the method of the present invention as set forth in claim 2, since the protective film is formed at a substrate temperature of 200° C. or higher, the adhesion to the substrate is improved, and the results of the vibration test are as follows. Also, it does not cause scratches and has excellent wear resistance.
【００１５】また、請求項３に記載の本発明方法によれ
ば、アルゴン圧を１ミリトル以下とするとともに基板温
度を２００℃以上にして前記保護膜を形成しているため
に、請求項１および２の相乗効果により、極めて耐摩耗
性に優れたものとなる。Further, according to the method of the present invention as set forth in claim 3, since the protective film is formed at an argon pressure of 1 mTorr or less and a substrate temperature of 200° C. or higher, The synergistic effect of the two results in extremely excellent wear resistance.
【００１６】[0016]
【実施例】以下、本発明の実施例を図１から図４につい
て説明する。Embodiments Hereinafter, embodiments of the present invention will be described with reference to FIGS. 1 to 4.
【００１７】図１は本発明方法によって製造された磁気
記録媒体の１例を示している。FIG. 1 shows an example of a magnetic recording medium manufactured by the method of the present invention.
【００１８】この磁気記録媒体は、先ず例えばＡｌ−Ｍ
ｇ合金等からなる適宜の厚さの基板１の上に、厚さが２
０μｍ程度のニッケルリン層２をメッキ等によって形成
し、そのニッケルリン層２の上面を研磨等の機械的方法
により適度に荒らして、その上に更に積層する他の層の
密着性を向上させる。そのニッケルリン層２の上に厚さ
が０．１μｍ程度のＣｒ下地層３を形成し、その上に厚
さが０．０６μｍ程度の磁性層４を形成する。この磁性
層４としては、例えばＣｏ−Ｃｒ−Ｔａ系の薄膜とする
とよい。その磁性層４の上に厚さが０．０３μｍ程度の
Ｃからなる保護膜５を本発明方法によって形成し、その
保護膜５の上に厚さが０．００３μｍ程度の潤滑剤層６
を形成することにより構成されている。This magnetic recording medium is first made of, for example, Al-M.
On a substrate 1 of an appropriate thickness made of g-alloy or the like,
A nickel phosphorus layer 2 of approximately 0 μm is formed by plating or the like, and the upper surface of the nickel phosphorus layer 2 is appropriately roughened by a mechanical method such as polishing to improve the adhesion of other layers further laminated thereon. A Cr underlayer 3 with a thickness of about 0.1 μm is formed on the nickel phosphorus layer 2, and a magnetic layer 4 with a thickness of about 0.06 μm is formed thereon. The magnetic layer 4 may be, for example, a Co--Cr--Ta based thin film. A protective film 5 made of carbon having a thickness of approximately 0.03 μm is formed on the magnetic layer 4 by the method of the present invention, and a lubricant layer 6 having a thickness of approximately 0.003 μm is formed on the protective film 5.
It is constructed by forming.
【００１９】前記保護膜５はＤＣマグネトロンスパッタ
リング法によって形成するとよく、その製造条件として
は、第１にＡｒガス圧力が１ミリトル以下の真空圧とし
、第２に基板温度を２００℃以上とし、第３にアルゴン
圧を１ミリトル以下とするとともに基板温度を２００℃
以上とするとよい。The protective film 5 is preferably formed by a DC magnetron sputtering method, and its manufacturing conditions include: firstly, the Ar gas pressure is a vacuum pressure of 1 mTorr or less, secondly, the substrate temperature is 200° C. or higher; In step 3, set the argon pressure to 1 mtorr or less and set the substrate temperature to 200°C.
It is better to set it to the above.
【００２０】アルゴン圧が１ミリトル以下であると、保
護膜５が緻密になり、ＣＳＳ特性が向上し耐摩耗性が優
れたものとなる。一方、アルゴン圧が１ミリトルを越え
ると、磁気記録媒体のＣＳＳ特性が劣ったものとなる。
従って、好ましくはアルゴン圧は０．６ミリトル以下が
適当である。[0020] When the argon pressure is 1 mTorr or less, the protective film 5 becomes dense, the CSS characteristics are improved, and the wear resistance is excellent. On the other hand, if the argon pressure exceeds 1 mTorr, the CSS characteristics of the magnetic recording medium will be poor. Therefore, the argon pressure is preferably 0.6 mTorr or less.
【００２１】また、基板温度が２００℃以上であると、
磁性層４等の下地への密着性が良くなり、振動試験の結
果においても傷が発生せず、耐摩耗性の優れたものとな
る。一方、基板温度が２００℃より低くなると、振動試
験の結果傷が発生するようになる。従って、好ましくは
基板温度は２２０℃以上が適当である。[0021] Furthermore, if the substrate temperature is 200°C or higher,
The adhesion of the magnetic layer 4 and the like to the base is improved, no scratches occur even in the vibration test results, and the wear resistance is excellent. On the other hand, if the substrate temperature is lower than 200° C., scratches will occur as a result of the vibration test. Therefore, the substrate temperature is preferably 220° C. or higher.
【００２２】また、アルゴン圧を１ミリトル以下とする
とともに基板温度を２００℃以上とすると、両者の相乗
効果により、保護膜５が緻密になるとともに、磁性層４
等の下地への密着性が良くなり、極めて耐摩耗性に優れ
たものとなる。Further, when the argon pressure is set to 1 mTorr or less and the substrate temperature is set to 200° C. or higher, the synergistic effect of both makes the protective film 5 dense and the magnetic layer 4
It has better adhesion to substrates such as, etc., and has extremely excellent abrasion resistance.
【００２３】このようにして保護膜５が緻密になるとと
もに、磁性層４等の下地への密着性が良くなると、ニッ
ケルリン層２の上面を荒らす機械加工の精度を荒くする
ことができ、また、高価な潤滑剤層６を薄くすることが
でき、磁気記録媒体自身の製造コストを低減させること
もできる。In this way, when the protective film 5 becomes dense and its adhesion to the underlying layer such as the magnetic layer 4 improves, the accuracy of machining for roughening the upper surface of the nickel phosphorous layer 2 can be made rougher, and , the expensive lubricant layer 6 can be made thinner, and the manufacturing cost of the magnetic recording medium itself can also be reduced.
【００２４】実施例１
図１に示す実施例において、アルゴン圧条件を０．４ミ
リトル、１．０ミリトルおよび２．５ミリトルとしてＣ
からなる保護膜５を形成して、それぞれのＣＳＳ特性を
図２に示した。Example 1 In the example shown in FIG. 1, the argon pressure conditions were 0.4 mTorr, 1.0 mTorr, and 2.5 mTorr
A protective film 5 consisting of the following was formed and the respective CSS characteristics are shown in FIG.
【００２５】図２より、アルゴン圧が１ミリトル以下の
場合においてＣＳＳ特性が優れていることがわかり、本
発明方法により耐摩耗性の優れた保護膜５が形成される
ことが明白となった。From FIG. 2, it was found that the CSS characteristics were excellent when the argon pressure was 1 mtorr or less, and it became clear that the protective film 5 with excellent wear resistance could be formed by the method of the present invention.
【００２６】実施例２
図１に示す実施例において、基板温度条件を２２０℃と
１００℃としてＣからなる保護膜５を形成して、それぞ
れの振動試験後の磁気記録媒体の表面の２００倍の顕微
鏡写真を図３および図４に示した。Example 2 In the example shown in FIG. 1, the protective film 5 made of C was formed under the substrate temperature conditions of 220° C. and 100° C., and the surface resistance of the magnetic recording medium was 200 times that of the surface of the magnetic recording medium after each vibration test. Microscopic photographs are shown in FIGS. 3 and 4.
【００２７】本発明方法による図３には、傷はほとんど
認められないが、従来方法による図４には、傷が認めら
れた。この比較結果からも本発明方法により耐摩耗性の
優れた保護膜５が形成されることが明白となった。In FIG. 3 obtained by the method of the present invention, almost no scratches are observed, but in FIG. 4 obtained by the conventional method, some defects are observed. It is clear from this comparison result that a protective film 5 with excellent wear resistance can be formed by the method of the present invention.
【００２８】なお、本発明は前記実施例に限定されるも
のではなく、必要に応じて変更することができる。It should be noted that the present invention is not limited to the above embodiments, and can be modified as necessary.
【００２９】[0029]
【発明の効果】このように本発明は構成され作用するも
のであるから、耐摩耗性に優れた保護膜を形成すること
ができ、磁気記録媒体の製造コストをも低減させること
ができる等の効果を奏する。[Effects of the Invention] Since the present invention is structured and operates as described above, it is possible to form a protective film with excellent wear resistance, and it is also possible to reduce the manufacturing cost of magnetic recording media. be effective.
【図１】本発明の磁気記録媒体の保護膜の製造方法によ
って製造された磁気記録媒体の１例を示す側面図FIG. 1 is a side view showing an example of a magnetic recording medium manufactured by the method for manufacturing a protective film for a magnetic recording medium of the present invention.
【図２
】本発明方法と従来方法とによって製造された保護膜の
ＣＳＳ特性を示す線図[Figure 2
] Diagram showing CSS characteristics of protective films manufactured by the method of the present invention and the conventional method
【図３】本発明方法によって製造された保護膜の振動試
験後の金属組織の顕微鏡写真[Figure 3] Microscopic photograph of the metal structure of the protective film produced by the method of the present invention after a vibration test
【図４】従来方法による図３と同様の図[Figure 4] A diagram similar to Figure 3 according to the conventional method
１ 基板 ２ ニッケルリン層 ３ Ｃｒ下地層 ４ 磁性層 ５ 保護膜 ６ 潤滑剤層 1 Board 2 Nickel phosphorus layer 3 Cr base layer 4 Magnetic layer 5 Protective film 6 Lubricant layer
Claims (3)
ング法により保護膜を形成する磁気記録媒体の保護膜の
製造方法において、アルゴン圧を１ミリトル以下にして
前記保護膜を形成することを特徴とする磁気記録媒体の
保護膜の製造方法。1. A method for manufacturing a protective film for a magnetic recording medium in which a protective film is formed on the magnetism of the magnetic recording medium by a sputtering method, characterized in that the protective film is formed at an argon pressure of 1 mTorr or less. A method for manufacturing a protective film for a magnetic recording medium.
リング法により保護膜を形成する磁気記録媒体の保護膜
の製造方法において、基板温度を２００℃以上にして前
記保護膜を形成することを特徴とする磁気記録媒体の保
護膜の製造方法。2. A method for manufacturing a protective film for a magnetic recording medium in which a protective film is formed on a magnetic layer of a magnetic recording medium by a sputtering method, characterized in that the protective film is formed at a substrate temperature of 200° C. or higher. A method for manufacturing a protective film for a magnetic recording medium.
リング法により保護膜を形成する磁気記録媒体の保護膜
の製造方法において、アルゴン圧を１ミリトル以下とす
るとともに基板温度を２００℃以上にして前記保護膜を
形成することを特徴とする磁気記録媒体の保護膜の製造
方法。3. A method for manufacturing a protective film for a magnetic recording medium in which a protective film is formed on a magnetic layer of a magnetic recording medium by a sputtering method, wherein the argon pressure is set to 1 mTorr or less and the substrate temperature is set to 200° C. or higher. A method for manufacturing a protective film for a magnetic recording medium, comprising forming the protective film.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP21942391A JPH04345916A (en) | 1991-05-22 | 1991-05-22 | Production of protective film of magnetic recording medium |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP21942391A JPH04345916A (en) | 1991-05-22 | 1991-05-22 | Production of protective film of magnetic recording medium |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH04345916A true JPH04345916A (en) | 1992-12-01 |
Family
ID=16735162
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP21942391A Withdrawn JPH04345916A (en) | 1991-05-22 | 1991-05-22 | Production of protective film of magnetic recording medium |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH04345916A (en) |
-
1991
- 1991-05-22 JP JP21942391A patent/JPH04345916A/en not_active Withdrawn
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A300 | Application deemed to be withdrawn because no request for examination was validly filed |
Free format text: JAPANESE INTERMEDIATE CODE: A300 Effective date: 19980806 |