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WO1999045537A1 - Support d'enregistrement magnetique, son procede de fabrication et appareil de memorisation magnetique fabrique par utilisation de ce support d'enregistrement magnetique - Google Patents

Support d'enregistrement magnetique, son procede de fabrication et appareil de memorisation magnetique fabrique par utilisation de ce support d'enregistrement magnetique Download PDF

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Publication number
WO1999045537A1
WO1999045537A1 PCT/JP1998/000886 JP9800886W WO9945537A1 WO 1999045537 A1 WO1999045537 A1 WO 1999045537A1 JP 9800886 W JP9800886 W JP 9800886W WO 9945537 A1 WO9945537 A1 WO 9945537A1
Authority
WO
WIPO (PCT)
Prior art keywords
magnetic
substrate
recording medium
magnetic recording
plasma
Prior art date
Application number
PCT/JP1998/000886
Other languages
English (en)
Japanese (ja)
Inventor
Yoshinori Honda
Yuuichi Kokaku
Mitsuhiro Shoda
Toshinori Ono
Original Assignee
Hitachi, Ltd.
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Hitachi, Ltd. filed Critical Hitachi, Ltd.
Priority to PCT/JP1998/000886 priority Critical patent/WO1999045537A1/fr
Priority to PCT/JP1998/004038 priority patent/WO1999045536A1/fr
Publication of WO1999045537A1 publication Critical patent/WO1999045537A1/fr

Links

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
    • G11B5/84—Processes or apparatus specially adapted for manufacturing record carriers
    • G11B5/8404—Processes or apparatus specially adapted for manufacturing record carriers manufacturing base layers
    • 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
    • G11B5/74—Record carriers characterised by the form, e.g. sheet shaped to wrap around a drum
    • G11B5/82—Disk carriers

Definitions

  • Magnetic recording medium method of manufacturing the same, and magnetic storage device using the same
  • the present invention relates to a magnetic storage device such as a magnetic disk device, and more particularly to a magnetic recording medium used for a head disk assembly (HDA) of a magnetic storage device and a method of manufacturing the same.
  • the present invention relates to an inexpensive and high-quality magnetic recording medium capable of high-density recording, a manufacturing method thereof, and an HDD using the magnetic recording medium.
  • a magnetic disk drive mainly includes a magnetic disk 1 and a magnetic head 2 that levitates above the magnetic disk 1 and performs recording and reproduction, as shown in FIG. 12, and also rotates the magnetic disk 1 Rotating mechanism 3, Magnetic head 2 Positioning head on rotating magnetic disk 1, Head positioning mechanism (servo mechanism) 4, RZW signal circuit 5 for recording and reproducing from magnetic disk using magnetic head Consists of
  • the floating gap between the magnetic disk 1 and the magnetic head 2 has become less than 0.05 m with the increase in recording density. It is desired to guarantee the sliding reliability at the time of contact.
  • the magnetic recording medium is composed of a substrate and a layered structure such as a magnetic film and a protective film formed on the substrate.Fine abrasive grains are applied to the surface of the substrate to prevent the magnetic head and the magnetic disk from attracting.
  • the method of forming fine grooves by circumferential or non-directional polishing called texture by the used machining method has been generally adopted.
  • Other methods include a so-called deposition texture in which fine projections are formed on the surface of a substrate or a magnetic film by sputtering, and a method in which a surface is coated with teflon particles after forming a protective film, and then a DRY etch is performed.
  • etching texture method for forming irregularities on the surface of the protective film by etching with a polishing method. Examples of these methods are disclosed in Japanese Patent Application Laid-Open Nos. Sho 61-19695 and Sho 61-2. 0 2 3 2 4 and Japanese Patent Application Laid-Open No. 58-53 0 26.
  • the purpose is to prevent adhesion between the magnetic head and the magnetic disk and to ensure reliability by contact start / stop (hereinafter referred to as CS / S). Requires a certain height. Therefore, the flying height of the magnetic head cannot be reduced below the height of the unevenness, and the low flying height of the magnetic head required to achieve the high recording density required at present is required. There was a problem that I could not do it.
  • the flying characteristics of the conventional magnetic head depend on the height at which the contact between the magnetic head and the magnetic recording medium starts (hereinafter referred to as H to), the protective film thickness on the magnetic film, and the lubricating film thickness. Defined. As a result, conventionally, the limit of H to was about 2 O rnn.
  • the height of the hill and the film thickness of the etched surface for etching the protective film cannot be absolutely reduced in terms of adhesion and strength, and the roughness of the substrate cannot be reduced. Since the hills are transferred to the surface of the protective film and appear, the height of the hills is limited to about 10 nm, and the remaining film thickness needs to be about 10 nm or about 15 nm, making it difficult to improve the flying characteristics. Regarding the uniformity of the hills, secondary and tertiary agglomeration cannot be avoided because the fine particles are applied and masked. This will inevitably cause thermal aspiration (TA) due to contact between the magnetic head and the large hills.
  • TA thermal aspiration
  • An object of the present invention is to solve the problems of the prior art, and to achieve extremely low levitation, high sliding resistance, high TPI and high TPI due to the disappearance of magnetic anisotropy, and reliability with low noise.
  • Another object of the present invention is to provide a magnetic recording medium and a magnetic storage device having high performance. For this purpose, as described above, it is essential to supply a process capable of making the surface of the magnetic disk uneven and uniform in the disk surface and selecting an arbitrary surface roughness.
  • the basic concept for obtaining a uniform surface is that the height of the concaves and convexes can be controlled uniformly in the plane, and the number of irregularities and the pitch of the irregularities are controlled.
  • the above-mentioned problems of the prior art are solved based on controllability, non-directionality such as machining, improvement of mechanical properties of the surface by processing only the surface, and the present invention. It achieves its purpose.
  • the position of the average center line of the surface roughness after processing is lower than the position of the line. In other words, it was found that under the conditions that would cause etching, the surface would not be uniform in height of the projections, but only roughened. Thus, by selecting the processing conditions, the present inventors did not change the average center line of the surface roughness of the substrate even after plasma processing, as shown in the lower part of Fig. 1, and changed the surface shape minutely. I found something that could be done. This can be achieved by treating the main constituent elements on the surface of the substrate without erosion by ions or radicals in the plasma.
  • the present inventors as shown in FIG. 2, FIG. 3, FIG. 4, FIG. 5, FIG. 6, FIG. 7, and FIG.
  • the height depends on the processing time and the energy of the plasma to be processed. Tsuchi was found to be dependent on the type of gas being processed and the pressure of the gas. Therefore, it is found that the magnetic recording medium required for the present invention can be obtained by appropriately selecting the processing conditions such as the processing time, the energy of the plasma to be processed, the gas type and the gas pressure, and performing the plasma processing. Was.
  • the hardness and Young's modulus of the surface treated by the present invention were measured with a thin film hardness tester manufactured by Nanoindenter, and as shown in Fig. 9, the hardness and Young's modulus were clearly improved as compared to before the treatment. Therefore, the effect of reducing the impact at the time of contact between the magnetic disk and the magnetic head can be greatly expected. Therefore, improvement of scratch resistance and crash resistance can be expected.
  • FIG. 1 is a diagram showing a roughness curve in the etching mode and the process of the present invention.
  • FIG. 2 is a diagram showing the relationship between plasma power and surface roughness.
  • FIG. 3 is a diagram showing the relationship between the plasma power and the pitch of the minute projections.
  • FIG. 4 is a diagram showing the relationship between plasma processing time and surface roughness.
  • FIG. 5 is a diagram showing the relationship between the plasma processing time and the pitch of the minute projections.
  • FIG. 6 is a diagram showing the relationship between the processing gas pressure and the surface roughness.
  • FIG. 7 is a diagram showing the relationship between the processing gas pressure and the pitch of the fine projections.
  • FIG. 8 is a diagram showing the relationship of surface roughness.
  • FIG. 9 is a diagram showing hardness and Young's modulus before and after the treatment of the present invention.
  • FIG. 10 is a diagram showing a manufacturing flowchart of this embodiment and a conventional example.
  • FIG. 11 is a diagram showing AFM images of the substrate surface of the present embodiment and the conventional example.
  • FIG. 12 is a schematic diagram of a magnetic disk drive.
  • FIG. 13 is a diagram showing processing conditions of the present example and a comparative example.
  • FIG. 14 is a diagram showing evaluation results for the present example and the comparative example.
  • FIG. 15 is a schematic view showing a magnetic recording medium according to this embodiment. BEST MODE FOR CARRYING OUT THE INVENTION
  • a Ni-P plating on aluminum followed by a machined flat surface, and a chemically strengthened glass substrate.
  • the substrate size is 3.5 inches for the aluminum / Ni-P substrate and 2.5 inches for the glass substrate.
  • FIG. 10 is a flowchart comparing the manufacturing process of the present invention with the manufacturing process of the prior art.
  • the center line average roughness (R a) Is preferably 0.15 nm or more and lOnm or less, and the center line peak height (Rp) is preferably 0.3 or more and 20 ⁇ m or less.
  • the ultimate pressure of the vacuum exhaust was set to IE-4 Pa or less.
  • the processing of the substrate surface is not limited to the processing method of the present embodiment, but includes a plasma etching method, a reactive ion etching method, a reactive ion beam etching method, a chemical assist ion beam etching method, an ion beam etching method, and a sputtering etching method.
  • Method or an induced plasma method such as ERC or ICP can be used.
  • a magnetic recording medium 1 was obtained by sequentially forming a base film 12, a magnetic film 13 and a protective film 14 on the substrate 11 of this example by a sputtering apparatus.
  • the underlayer 12 is sputtered to 30 nm in an Ar gas atmosphere using a Cr target, and the magnetic film 13 is sputtered in an Ar gas atmosphere using a CoCrPt target.
  • the sputter was set to 25 nm.
  • the protective film 14 was sputtered in an Ar gas atmosphere using a graphite target to a thickness of 15 nm.
  • the surface of the magnetic recording medium was rubbed and dust was removed while rotating the substrate with a tape with abrasive grains to clean the surface. Thereafter, a fluorine-based lubricant was applied by DiP to a thickness of 15 A, and cured at 80 ° C. in a clean oven to form a lubricant film 15.
  • the magnetic recording media of Examples 1 to 10 were evaluated as described below, and the results are shown in FIG.
  • the evaluation methods include tangential force, CSS resistance, frequency of scratches caused by random seek, levitation of magnetic head (H to), T.A frequency of occurrence, and magnetostatic properties (Hc, S *, B rt ) And magnetic anisotropy. From FIG. 14, it is clear that this example is superior in any of the evaluation results as compared with the comparative example, and it can be seen that the object of the present invention is sufficiently satisfied.
  • any other manufacturing method can be used as long as it is a surface treatment method using a plasma in a vacuum, and the latitude in equipment is increased.
  • the present invention there is no need for the conventional substrate processing, cleaning process and DEPO-TEX formation at the time of film formation, etching by applying particles after forming the protective film, and the cleaning process. You can check. In addition, it has an excellent cost performance.
  • the surface condition was measured using an AFM (Atomic Force Microscope) to cover an area of 10 ⁇ m 2 . It was measured. The result is shown in Fig. 11 as an image of unevenness. As can be seen from the figure, it is clear that the substrate surface has been subjected to a uniform surface treatment and has extremely fine irregularities due to the treatment in this embodiment.
  • the underlying film, magnetic film, protective film, and lubricating film of the magnetic recording medium are not limited to those of the present embodiment, but include a two-layer underlying film, an alloy underlying film, a Co-based magnetic film, It is also possible to use any combination of a protective film for the layer, reactive sputtered carbon (carbon film containing H2, N2, etc.), and PCVD carbon film. In particular, the combination with a high-strength H 2, N 2 -containing carbon protective film results in even better results.
  • the CSS zone is LZT
  • the data surface can be processed with the processing method of the present invention to achieve a very low flying height and easy high recording density surface. It is clear that high-density recording media with high performance can be produced. Further, by subjecting the substrate to the surface treatment of the present invention, the in-plane magnetic anisotropy of the magnetic layer disappears, and a magnetic recording medium having isotropic magnetic characteristics is obtained.
  • the magnetic recording medium has high reliability and high TPI due to disappearance of magnetic anisotropy and low noise.
  • the present invention it is possible to realize a magnetic disk medium capable of achieving extremely low flying height and to supply a sufficiently clean substrate without using an unstable and special cleaning technique such as machining.
  • a cheaper and higher quality magnetic recording medium can be obtained. Therefore, not only can the reliability of the HDD be ensured, but also a system such as a high-density HDD with a high recording density and a high capacity can be supplied.
  • the total amount of investment in manufacturing equipment itself is reduced by eliminating the process of machining such as machining in the manufacturing process, and the manufacturing yield power is significantly increased, so that the cost of magnetic disks is reduced.
  • the cost of HDDs can be greatly reduced.
  • the in-plane magnetic anisotropy of the magnetic layer disappears, and a magnetic recording medium having isotropic magnetic characteristics is obtained.

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  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Manufacturing Of Magnetic Record Carriers (AREA)
  • Magnetic Record Carriers (AREA)

Abstract

L'invention concerne un procédé de traitement au plasma de la surface de substrat d'un support d'enregistrement magnétique pour obtenir une rugosité de surface uniforme et arbitraire sur la surface entière, sans laisser des ions ou des radicaux, présents dans le plasma, éroder les éléments principaux constituant la surface. Ce procédé peut permettre d'éviter l'adhérence de la tête magnétique au support d'enregistrement magnétique, d'obtenir une grande fiabilité d'adhérence magnétique, une faible hauteur de survol, un grand nombre de pistes au pouce (TPI) grâce à l'isotropie de caractéristiques magnétiques et un faible bruit. Le procédé peut, en outre, permettre d'obtenir un appareil de mémorisation magnétique à haute densité d'enregistrement et de grande fiabilité.
PCT/JP1998/000886 1998-03-04 1998-03-04 Support d'enregistrement magnetique, son procede de fabrication et appareil de memorisation magnetique fabrique par utilisation de ce support d'enregistrement magnetique WO1999045537A1 (fr)

Priority Applications (2)

Application Number Priority Date Filing Date Title
PCT/JP1998/000886 WO1999045537A1 (fr) 1998-03-04 1998-03-04 Support d'enregistrement magnetique, son procede de fabrication et appareil de memorisation magnetique fabrique par utilisation de ce support d'enregistrement magnetique
PCT/JP1998/004038 WO1999045536A1 (fr) 1998-03-04 1998-09-09 Support d'enregistrement magnetique, procede de production de celui-ci et memoire magnetique

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/JP1998/000886 WO1999045537A1 (fr) 1998-03-04 1998-03-04 Support d'enregistrement magnetique, son procede de fabrication et appareil de memorisation magnetique fabrique par utilisation de ce support d'enregistrement magnetique

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WO1999045537A1 true WO1999045537A1 (fr) 1999-09-10

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PCT/JP1998/000886 WO1999045537A1 (fr) 1998-03-04 1998-03-04 Support d'enregistrement magnetique, son procede de fabrication et appareil de memorisation magnetique fabrique par utilisation de ce support d'enregistrement magnetique
PCT/JP1998/004038 WO1999045536A1 (fr) 1998-03-04 1998-09-09 Support d'enregistrement magnetique, procede de production de celui-ci et memoire magnetique

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPWO2008007547A1 (ja) * 2006-07-13 2009-12-10 コニカミノルタオプト株式会社 ガラス基板の製造方法、磁気ディスクの製造方法および磁気ディスク

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JPS5982625A (ja) * 1982-11-01 1984-05-12 Nippon Telegr & Teleph Corp <Ntt> 磁気デイスク基板の作製方法
JPS62219224A (ja) * 1986-03-19 1987-09-26 Fujitsu Ltd 磁気記録媒体及びその製造方法
JPH0461625A (ja) * 1990-06-27 1992-02-27 Victor Co Of Japan Ltd ガラス磁気ディスク
US5119258A (en) * 1990-02-06 1992-06-02 Hmt Technology Corporation Magnetic disc with low-friction glass substrate
US5322595A (en) * 1993-03-19 1994-06-21 Kabushiki Kaisha Kobe Seiko Sho Manufacture of carbon substrate for magnetic disk
US5366607A (en) * 1991-08-05 1994-11-22 Hmt Technology Corporation Sputtering target and assembly
EP0671728A2 (fr) * 1994-03-04 1995-09-13 Shin-Etsu Chemical Co., Ltd. Amélioration au milieu d'enregistrement magnétique
US5560977A (en) * 1993-06-18 1996-10-01 Kao Corporation Magnetic recording medium and manufacturing the same
JPH08315356A (ja) * 1995-05-15 1996-11-29 Hitachi Ltd 凹凸の形成方法及び磁気記録媒体の製造方法
US5635037A (en) * 1993-08-02 1997-06-03 Industrial Technology Research Institute Method of texture by in-situ masking and etching for thin film magnetic recording medium
JPH09180179A (ja) * 1995-12-22 1997-07-11 Mitsubishi Chem Corp 磁気記録媒体およびその製造方法
US5650237A (en) * 1994-11-21 1997-07-22 Kao Corporation Magnetic recording medium having a metallic magnetic layer and an aluminum alloy underlayer
US5718811A (en) * 1996-02-28 1998-02-17 Seagate Technology, Inc. Sputter textured magnetic recording medium
US5733370A (en) * 1996-01-16 1998-03-31 Seagate Technology, Inc. Method of manufacturing a bicrystal cluster magnetic recording medium

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JP2512113B2 (ja) * 1988-11-07 1996-07-03 松下電器産業株式会社 薄膜型磁気ディスク
JPH07230620A (ja) * 1994-02-16 1995-08-29 Mitsubishi Chem Corp 磁気ディスク用基板及び磁気ディスク
JPH07244947A (ja) * 1994-03-08 1995-09-19 Hitachi Ltd 磁気ディスク装置、磁気ディスクおよび磁気ディスクの製造方法
JPH08147692A (ja) * 1994-11-28 1996-06-07 Mitsubishi Chem Corp 磁気記録媒体の製造方法
JPH09138944A (ja) * 1995-11-10 1997-05-27 Fujitsu Ltd 非磁性基板、磁気記録媒体、磁気記録装置及び層表面の粗面化方法

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5982625A (ja) * 1982-11-01 1984-05-12 Nippon Telegr & Teleph Corp <Ntt> 磁気デイスク基板の作製方法
JPS62219224A (ja) * 1986-03-19 1987-09-26 Fujitsu Ltd 磁気記録媒体及びその製造方法
US5119258A (en) * 1990-02-06 1992-06-02 Hmt Technology Corporation Magnetic disc with low-friction glass substrate
JPH0461625A (ja) * 1990-06-27 1992-02-27 Victor Co Of Japan Ltd ガラス磁気ディスク
US5366607A (en) * 1991-08-05 1994-11-22 Hmt Technology Corporation Sputtering target and assembly
US5322595A (en) * 1993-03-19 1994-06-21 Kabushiki Kaisha Kobe Seiko Sho Manufacture of carbon substrate for magnetic disk
US5560977A (en) * 1993-06-18 1996-10-01 Kao Corporation Magnetic recording medium and manufacturing the same
US5635037A (en) * 1993-08-02 1997-06-03 Industrial Technology Research Institute Method of texture by in-situ masking and etching for thin film magnetic recording medium
EP0671728A2 (fr) * 1994-03-04 1995-09-13 Shin-Etsu Chemical Co., Ltd. Amélioration au milieu d'enregistrement magnétique
US5650237A (en) * 1994-11-21 1997-07-22 Kao Corporation Magnetic recording medium having a metallic magnetic layer and an aluminum alloy underlayer
JPH08315356A (ja) * 1995-05-15 1996-11-29 Hitachi Ltd 凹凸の形成方法及び磁気記録媒体の製造方法
JPH09180179A (ja) * 1995-12-22 1997-07-11 Mitsubishi Chem Corp 磁気記録媒体およびその製造方法
US5733370A (en) * 1996-01-16 1998-03-31 Seagate Technology, Inc. Method of manufacturing a bicrystal cluster magnetic recording medium
US5718811A (en) * 1996-02-28 1998-02-17 Seagate Technology, Inc. Sputter textured magnetic recording medium

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPWO2008007547A1 (ja) * 2006-07-13 2009-12-10 コニカミノルタオプト株式会社 ガラス基板の製造方法、磁気ディスクの製造方法および磁気ディスク
JP4631971B2 (ja) * 2006-07-13 2011-02-16 コニカミノルタオプト株式会社 ガラス基板の製造方法および磁気ディスクの製造方法
US8153284B2 (en) 2006-07-13 2012-04-10 Konica Minolta Opto, Inc. Method for fabricating a glass substrate, method for fabricating a magnetic disk, and magnetic disk

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