JPH04247319A - Magnetic recording medium and manufacture thereof - Google Patents

Abstract

PURPOSE: To improve the characteristics of an overcoating layer for the magnetic layer of a magnetic recording medium. CONSTITUTION: This magnetic recording medium has the constitution obtd. by successively superposing a substrate 10, the magnetic layer 12, the overcoating layers 13, 15 and a lubricating layer 16. The overcoating layer 13 consists of a first material composed mainly of carbon. The overcoating layer 15 consists of a second material selected from metal oxide, oxynitride and oxycarbide having affinity to a lubricant. The overcoating layer formed by doping a second material to the overcoating layer consisting of the first material may be used in place of the two overcoating layers 13, 15.

Description

[Detailed description of the invention]

0001

FIELD OF INDUSTRIAL APPLICATION This invention relates to the field of magnetic recording media, and more particularly has an overcoat that provides excellent mechanical durability and affinity for applied disk/head lubricants. , relating to magnetic recording media.

0002

BACKGROUND OF THE INVENTION It is known in the art to provide overcoat layers over the exposed surfaces of magnetic recording media. For example, sputtered films have been used as protective overcoats on thin film magnetic media.

Overcoats of this type must have sufficient hardness to withstand accidental high-speed collisions with, for example, magnetic read/write transducer heads. Such an overcoat must also be compatible with lubricants such as hydrocarbon and fluorine compounds commonly used to lubricate the interface between the magnetic medium and the transducing head. Additionally, these protective overcoats must be resistant to moisture or water penetration, as such penetration is likely to have the deleterious effect of corroding the underlying magnetic recording layer or film. Must be.

A number of materials have been used in the art to provide overcoats for magnetic recording media. These materials are generally classified into the following two categories.

The first category of overcoat materials includes metal oxides, metal carbides, and metal nitrides, such as zirconium oxide stabilized with yttrium oxide. A second category of overcoat materials includes sputter-deposited carbon films, such as diamond-like carbon (DLC) films. As is known in the art, these two categories of materials each have advantages and disadvantages.

For example, amorphous diamond-like carbon films are generally more resistant to fracture than zirconium oxide films and other brittle crystalline oxide films. However, the advantage of zirconium oxide and other such oxides is that they generally have a desirable affinity for lubricants such as perfluorinated lubricants and/or lubricating hydrocarbons that are commonly applied to recording media during the manufacturing process. It is about providing.

When the magnetic recording medium is in the form of a rigid or hard disk, maintaining a supply of lubricant at the disk/head transition interface is critical to the mechanical reliability of a direct access storage device (DASD) or hard file. is particularly important for If the disk surface is constructed and arranged to have an affinity for lubricant,
Lubricant losses caused by phenomena such as spin-off are minimized. One effect of the lubricating layer is to prevent or significantly reduce the penetration of moisture into the magnetic recording layer. Furthermore, the lubricant that is tightly bound to the disk surface is
Its function is to prevent displacement of the lubricant by low molecular weight reactive hydrocarbons that may be present in the lubricant.

The use of zirconium oxide overcoats typically provides a high density of bond sites for the attachment of commonly used perfluorinated lubricants. Therefore, zirconium is generally the overcoat material of choice when this parameter is considered.

[0009] Considering generally how these two categories of overcoats are deposited as overcoat layers or overcoat films on magnetic recording layers or magnetic recording films, the first category described above is considered. Tsune overcoat material (
Metal oxides, metal carbides and metal nitrides) generally provide high electrical resistance and therefore must be deposited onto the magnetic recording layer or film using well known methods such as radio frequency plasma or sputter deposition.

Sputtered carbon films, such as diamond-like carbon, can be sputter deposited as an overcoat onto the magnetic recording film using well-known direct current or radio frequency sputtering techniques.

RF sputter deposition is considerably slower and more expensive than DC sputter deposition. Therefore, considering factors such as ease of manufacture and cost, carbon and other DC sputter depositable materials are preferred.

[0012] It is desirable to provide an overcoat material that has the above-mentioned advantages of tackiness and cost of carbon overcoat materials and the above-mentioned lubricant adhesion properties of metal oxides, metal carbides, and metal nitrides.

It is an object of the present invention to provide an improved protective overcoat for magnetic recording media that has excellent mechanical durability, low friction, and affinity for recording media lubricants.

Another object of the present invention is to combine the tenacity and cost advantages of carbon overcoat materials with the lubricant adhesion advantages of overcoat materials such as metal oxides, metal carbides, and metal nitrides. An object of the present invention is to provide a magnetic recording overcoat material.

[0015]

SUMMARY OF THE INVENTION The present invention provides a method for applying a multilayer overcoat (FIG. 1) or a single doped overcoat layer (FIG. 2) onto the surface of a magnetic recording medium, such as on a thin magnetic film of a rigid disk. Provided to.

In the multilayer structure of the present invention (FIG. 1), the carbon layer,
Hard carbon layer or diamond-like carbon (DLC) layer 13
is overcoated with a thin layer 15 of a metal, carbide, or nitride, such as silicon or tungsten. Then,
Layer 15 is allowed to oxidize at atmospheric conditions for a period of time to form an oxide top portion thereon, after which a lubricating layer 17 is applied over this oxide portion.

In the single layer structure (FIG. 2) of the present invention, the carbon layer,
The hard carbon layer or diamond-like carbon layer 20 is doped with a metal such as silicon, a carbide or a nitride. Again, doped layer 20 is oxidized for a period of time to form a top portion of oxide thereon. This oxidation step can be performed in a room temperature environment or in an oxidizing plasma.

According to the present invention, the oxidation step has the effect of changing the chemical properties of the surface of the carbon-based layer. A lubricating layer 17 is then applied to this oxide top surface portion.

[0019] In one aspect, the present invention includes (1) a rigid non-magnetic disk-shaped substrate, (2) a thin magnetic recording film vacuum-deposited on the substrate, and (3) a thin magnetic recording film vacuum-deposited on the recording film. and (4) a carbon-based film selected from metal oxides, oxynitrides, and oxidized carbides. A rigid magnetic recording disk is provided having a hard-working oxide film and (5) a lubricant film selected from hydrocarbon lubricants and perfluoro lubricants.

The present invention further includes (1) a step of providing a vacuum-deposited thin magnetic recording film; (2) a material mainly composed of carbon and having an affinity for a lubricant, a metal oxide,
(3) providing a vacuum-deposited overcoat film on the recording film, comprising another material selected from oxynitrides and oxidized carbides; and (3) providing a lubricant film on the overcoat film. A method of manufacturing a magnetic recording disk is provided.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention provides an improved protective overcoat for magnetic recording media, such as a protective overcoat for thin magnetic recording films that can be used with rigid disks, floppy disks, card and tape media.

A preferred embodiment of the present invention provides an overcoat for magnetic recording media in the form of, but not limited to, rigid disks or hard disks, which are well known in the art. This type of disk is typically used in direct access storage devices (DASD) and serves to store binary data for use in data processing or computer systems. The present invention is useful with any known recording method, such as horizontal magnetic recording or perpendicular magnetic recording.

The protective overcoat means of the present invention provides excellent mechanical durability and has compatibility with known lubricants.

In a first embodiment of the invention shown in FIG. 1, the overcoat layer 13, 15 is a carbon layer with a thin layer 15 of a metal oxide, oxynitride, oxycarbide, for example silicon oxide thereon. , a hard carbon layer or a diamond-like carbon (DLC) layer 13. The thin layer 15 serves to enhance the affinity of the disk for the disk/head lubricating film 16 that is subsequently applied to the overcoat layers 13,15.

Layer 15 can be deposited from a metal, nitride or carbide target and then oxidized during a separate oxidation step, or an oxide target can be used to deposit layer 15 directly as an oxide. You can also.

In a second embodiment of the invention, shown in FIG. 2, a carbon, hard carbon or diamond-like carbon overcoat layer 20 is doped with a metal, carbide or nitride. The oxidation step provides the top surface 21 of layer 20 with an oxide layer that has an affinity for head/disk lubrication layer 16. Again, layer 20 can be formed directly using an oxide target.

As used herein, the term "oxidized" refers to the top surface 19 of layer 15 (FIG. 1) or the top surface 2 of layer 20.
1 (FIG. 2) for several hours in an indoor atmospheric environment. It is also possible to perform such oxidation by treating such surfaces with an oxidizing plasma, layer 15 (Fig.
) or the target material for sputter depositing layer 20 (FIG. 2) can also be formed from the required oxide material.

An important feature according to the invention is that the surface of such a layer has an oxide component which has an affinity for the subsequently applied lubricating layer 16.

Preferred embodiments of the present invention provide carbon or carbon-like films 13 and 20, which can be characterized as sputter-deposited hydrogenated amorphous carbon films.

In a preferred embodiment of the invention, a hard disk or rigid disk horizontal magnetic recording disk is mounted on a thin, non-magnetic disk-shaped substrate 10 of FIGS. 1 and 2 on one or both planar surfaces 11. A magnetic layer, ie magnetic recording film 12, is first created by sputter deposition. For simplicity of illustration, only one such planar surface 11 is shown in FIGS. 1 and 2. Substrate 10 typically includes, but is not limited to,
Protective N on one or both parallel planar surfaces 11
It is a flat aluminum disk plated with an iP layer. Substrate 10 can also include a non-magnetic material such as glass, ceramic, or a composite of glass and ceramic.

Magnetic recording film 12 can be formed from any number of suitable alloys, such as iron- or cobalt-based alloys, although the composition thereof is not critical to the invention. Useful magnetic films include, for example, sputtering, vacuum deposition,
a Co-Pt film deposited by any suitable thin film manufacturing method known to those skilled in the art, such as plating;
Co-Cr film, Co-pt-Cr film, Co-Ni-Cr
Co-Ta-Cr film.

As is well known to those skilled in the art, the disks of FIGS. 1 and 2 include a thin film of Cr or some other metal on surface 11 underlying magnetic recording layer 12. You don't have to be prepared either. This kind of membrane is
For example, it serves to provide a preferable crystal orientation for the thin magnetic film 12.

The above disc fabrication steps are well known to those skilled in the art and will not be described in detail herein for the sake of brevity.

In the first embodiment of the present invention shown in FIG. 1, an overcoat film 13 of carbon, hard carbon, or diamond-like carbon (DLC) is applied to the magnetic recording film 1 of the disk.
2 on the exposed surface 14. Recording layer 12, although not critical to the invention, has a thickness in the range of 100-200 Angstroms.

The deposition step of the overcoat film 13 can be performed, for example, by radio frequency sputtering, DC sputtering, or radio frequency/DC sputtering from a carbon target using argon as the deposition gas and with or without a doping gas such as hydrogen or water. Perform using sputtering. Alternatively, the diamond-like carbon layer can be deposited by plasma-assisted chemical vapor deposition (PACVD) or chemical vapor deposition (PACVD) from a carbon source such as methane gas or acetylene gas.
It can also be deposited by a CVD method.

The resulting diamond-like carbon overcoat film 13 has a typical thickness of about 15-40 nm.
within the range of

A thinner overlayer film 15 of metal, carbide or nitride is then deposited over the diamond-like carbon overcoat layer 13. The materials most suitable for use at this stage of the invention are Si, Cr, Mo, W, V
, Nb, Ta, Ti, Zr, Hf, Fe, Al, etc., which will later form a chemically stable oxide. Among this group, the metal-semiconductor silicon, which is a metal-like element, is preferred. As overlayer 15 a metal or a carbide or nitride compound is deposited.

After depositing the selected material (ie, metal, carbide or nitride) as a thin film 15, surface oxidation of the thin film at room temperature conditions exposes an excellent bonding site for a lubricating film 16 according to the present invention. A solid oxide surface 19 is rapidly established. As mentioned above, this separate oxidation step can be eliminated by depositing thin film 15 as an oxide.

As mentioned above, the primary function of the thin oxidized metal/carbide/nitride overlayer 15 is to provide an oxide surface that enhances the adhesion of the disk lubricant layer 16 to the disk. Examples of such lubricants are hydrocarbon lubricants, perfluorinated lubricants or perfluorinated compound lubricants. The lubricating layer 16 covers the disk head/
It functions to lubricate the disk interface 17. Typical thicknesses of adhesive layer 15 range from a few molecules, for example about 1-10 nm.

The thickness of the lubricating layer 16 is not critical to the invention, but typical thicknesses range from about 10 to 50 angstroms.

The method for attaching the overlayer 15 is as follows:
Not important to the invention. The overlayer can be deposited by DC sputtering, radio frequency sputtering or DC/RF sputtering, or by using chemical vapor deposition or plasma assisted chemical vapor deposition.

Although the invention is not limited thereto, one example of the process for forming membranes 13 and 15 of FIG.
Carbon film 13 is sputter deposited to a thickness of about 300 Angstroms by DC magnetron sputtering from a graphite target using a sputtering gas containing about 2-10% hydrogen in argon. Sputter pressures in the range of approximately 5-30 mTorr were used. Sputter deposition rates ranged from about 50 to 200 angstroms per minute. Silicon film 15 was then sputter deposited on top of film 13 using DC magnetron sputtering in the presence of argon gas. As a result, a silicon film 15 having a thickness in the range of about 20 to 50 angstroms was obtained. To obtain the oxidized surface 19, the membrane 15 was left to oxidize in a room temperature environment for approximately 24 hours.

FIG. 2 shows the diamond-like carbon layer 13 of FIG.
and in which the overlayer 15 is replaced by a carbon-based overcoat layer, a hard carbon overcoat layer, or a diamond-like carbon overcoat layer 20 doped with metal, carbide or nitride components. An example is shown. This component is then oxidized to form an oxide that has an affinity for the head/disk lubricating layer 16 of the disk.

The doping concentration of the carbon-based layer 20 is fairly low, for example in the range of about 1-30% by weight relative to the carbon-based layer.

The doped layer 20 is generally formed using a carbon-based material and a selected metal at the above-mentioned doping concentration.
Preferably, layer 20 is sputter deposited from a composite material target consisting of a carbide or nitride. Alternatively, the doped carbon layer 20 may be formed by chemical vapor deposition (CV).
D) or can be formed using plasma assisted chemical vapor deposition (PACVD). For example, layer 20 can be formed by reactive sputter deposition of a carbon-containing gas, ie, a hydrocarbon gas such as methane, onto a metal, carbide, or nitride target.

Doping of layer 20 can also be performed by ion implantation of the selected metal, carbide or nitride into a previously deposited carbon, hard carbon or diamond-like carbon overcoat film 20. . Useful metals again include Si, Cr, Mo,
Examples include W, V, Nb, Ta, Ti, Zr, Hf, Fe, and Al.

No matter what technique is used, the lubricating layer 1
6, an exposed oxidized surface 21 is provided.

[0048] Although not limited to, a typical thickness of overcoat film 20 is about 15-40 nm.
The range is fine.

In the embodiment of the invention described with respect to FIGS. 1 and 2, oxidized surface 19 in FIG. 1 and oxidized surface 21 in FIG.
gives perfluoropolyether (PFPE) lubricants, especially those with active end groups within the lubricant molecule, an affinity for lubricating hydrocarbons. The primary binding mechanism of such lubricants to oxidized surfaces 19, 21 is believed to be through the binding of active end groups of the lubricants to OH groups present on oxidized surfaces 19, 21. In the case of PFPE lubricants, it is believed that secondary bonding occurs to the PFPE backbone. The higher the density of OH groups on the surfaces 19, 21, the greater the number of active lubricant binding sites and the more strongly the lubricant layer 16 is bonded to layer 15 of FIG. 1 and layer 20 of FIG. 2.

The lubricating layer 16 not only reduces head-to-disk friction, but also reduces water penetration into the underlying magnetic recording layer 12.

Although the invention is not so limited, one example of a process for forming film 20 of FIG. 2 uses a sputtering gas containing about 2-10% hydrogen in argon, A tungsten-doped carbon-based film 20 is sputter deposited to a thickness of approximately 300 Angstroms by DC magnetron sputtering from a composite target of graphite and 6% tungsten. Sputter pressures in the range of approximately 5-20 mTorr were used. Sputter deposition rates ranged from about 50 to 200 angstroms per minute. The membrane 20 was then left to oxidize in a room temperature environment for about 24 hours to obtain an oxidized surface 21.

FIG. 3 shows the relationship between disk/head friction and disk start/stop for three types of disk assemblies, each assembly having eight recording surfaces carried by four rigid recording disks. A graph plotted as a function of motion.

Two of these disk assemblies
One is of the type shown in FIG. Curves C, D, E
is for the first disc assembly of FIG.
1 with an oxidized silicon overlayer 15 of m.

Curves A and B are for disk assemblies that did not implement the invention. In Figure 3,
It is shown that this disk assembly does not include an oxidized overlayer 15 (ie, the thickness of the overcoat layer is shown to be 0 nm).

As can be seen in FIG. 3, the disk assembly of curve C--G provides a relatively flat, stable, and acceptable frictional surface for the disk's transducing head throughout the 15,000 start/stop cycle test. , and the disk assemblies of curves A and B (i.e., disk assemblies that do not incorporate the present invention) exhibit unacceptably high heads after only about 1000 start/stop cycles of the disk assembly. /Disk friction interface is shown.

Curve C--G of FIG. 3 represents a preferred embodiment of the invention in which layer 15 of FIG. 1 and the doping component of layer 20 of FIG. The lubricant-receiving surfaces 19, 21 of generally include silicon dioxide.

Although this invention has been described in terms of its preferred embodiments, it should be recognized that other embodiments will occur to those skilled in the art that are within the spirit and scope of the invention.

[0058]

Advantages of the overcoat material of the present invention are that it can be sputter deposited at a high deposition rate, the material has high electrical resistivity and hardness, is tough and wear resistant, and is free from hydrocarbon and fluorine compound lubrication. be compatible with and have affinity for the magnetic recording layer, be optically transparent to permit optical inspection of disk defects, and form a pore-free corrosion protection barrier on top of the magnetic recording layer.

Additionally, the overcoat material of the present invention can be sputter deposited using a DC magnetron method.

[Brief explanation of the drawing]

FIG. 1: Metal (i.e., silicon) oxides that serve to enhance affinity for disk/head lubricating films.
1 is a cross-sectional view of the top surface of a rigid magnetic recording disk according to the present invention showing an overcoat film consisting of a diamond-like carbon (DLC) film with a thin oxide film of an oxynitride or oxycarbide compound thereon; FIG.

FIG. 2: A surface doped with a carbon-based overcoat film consisting of a metal (i.e., silicon) oxide, oxycarbide, or oxynitride to provide affinity for a subsequently applied head/disk lubricating film. is provided,
FIG. 2 is a cross-sectional view similar to FIG. 1;

[Figure 3] A device with overcoat films of two different thicknesses.
In a two-disk assembly of the type shown in Figure 1, friction at the disk/head interface is significantly reduced during disk start/stop operations compared to a single disk assembly without such an overcoat film. This is a graph plotted as a function.

[Explanation of symbols]

10 Substrate 12 Magnetic layer 13 Diamond-like carbon (DLC) overcoat layer (film) 15 Overlayer 16 Lubricating layer 17 Head/disk interface 20 Doped diamond-like carbon (DLC) overcoat layer (film)

Claims (38)

[Claims] Claim 1: A magnetic recording film comprising a thin magnetic recording film, a material mainly composed of carbon, and a second material selected from metal oxides, oxynitrides, and oxycarbides, which has an affinity for lubricants. an overcoat film on the recording film;
and a lubricating film on the overcoat film. 2. The recording film according to claim 1, wherein the recording film is selected from an alloy mainly composed of iron and an alloy mainly composed of cobalt.
recording medium. 3. The recording medium of claim 2, wherein the lubricating film is selected from hydrocarbon compounds and perfluorinated compounds. 4. The recording medium of claim 3, comprising a non-magnetic disk-shaped substrate having said recording film deposited thereon. 5. The recording medium according to claim 4, further comprising a thin chromium film between the substrate and the recording film. 6. The recording medium of claim 5, wherein said second material is silicon oxide. 7. The carbon-based material is a diamond-like carbon material, and the metal oxide is Si, Cr,
Mo, W, V, Nb, Ta, Ti, Zr, Hf, Fe,
The recording medium according to claim 1, wherein the recording medium is selected from oxides of Al. 8. The thickness of the overcoat film is about 15 to 4.
8. The recording medium of claim 7, wherein the recording medium is in the range of 0 nm. 9. Claim 8, wherein the recording film is selected from an iron-based alloy and a cobalt-based alloy.
recording medium. 10. The recording medium according to claim 9, wherein the lubricating film is selected from hydrocarbon compounds and perfluoro compounds. 11. The overcoat film comprises a first film made of a carbon-based material on the magnetic recording film, and a metal oxide, oxynitride, or oxidized carbide on the carbon-based film. 2. The recording medium according to claim 1, further comprising a second film selected from the above. 12. The recording medium according to claim 11, wherein said carbon-based material comprises diamond-like carbon. 13. The second film is made of silicon oxide,
The recording medium according to claim 12. 14. The first film has a thickness of about 15 to 40 nm.
14. The recording medium of claim 13, wherein the second film has a thickness in the range of about 1 to 10 nm. 15. The recording medium according to claim 14, wherein the recording film is selected from an iron-based alloy and a cobalt-based alloy. 16. The recording medium according to claim 15, wherein the lubricating film is selected from hydrocarbon compounds and perfluoro compounds. 17. The overcoat film means comprises a second film selected from metal oxides, oxynitrides, and oxide carbides.
2. The recording medium of claim 1, comprising a film of carbon-based material doped with a material. 18. The doping concentration of the carbon-based material is about 1 to 1 with respect to the carbon-based material.
18. The recording medium of claim 17, in the range of 30% by weight. 19. The carbon-based material is a diamond-like carbon material, and the metal oxide is a metal such as Si, Cr, Mo, W, V, Nb, Ta, Ti, or Zr.
19. The recording medium according to claim 18, wherein the recording medium is selected from oxides of , Hf, Fe, and Al. 20. The recording medium of claim 18, wherein the carbon-based material is diamond-like carbon and the doping material is silicon. 21. A rigid non-magnetic disk-shaped substrate, a thin magnetic recording film vacuum-deposited on the substrate, a film mainly composed of carbon and vacuum-deposited on the recording film, and a carbon-based film vacuum-deposited on the recording film; an oxide film selected from metal oxides, oxynitrides and oxidized carbides on the main film, which functions to provide affinity for a lubricating film to be deposited later, and on the oxide film, a lubricating film selected from hydrocarbon lubricants and perfluorinated lubricants. 22. The magnetic recording disk according to claim 21, wherein said carbon-based film is a hydrogenated amorphous carbon film. 23. The magnetic recording disk of claim 22, wherein said oxide film is silicon oxide. 24. The magnetic recording disk of claim 23, wherein said substrate comprises an aluminum disk coated with a non-magnetic protective layer. 25. The magnetic recording disk according to claim 24, wherein said recording film is selected from an alloy mainly composed of iron and an alloy mainly composed of cobalt. 26. Claim 2 further comprising a thin film of chromium on the surface of the aluminum disk underlying the magnetic recording film.
5 magnetic recording disk. 27. The thickness of the magnetic recording film is about 10 to 20 nm.
m, the thickness of the carbon-based film is in the range of about 15 to 40 nm, the thickness of the oxide film is in the range of about 1 to 10 nm, and the thickness of the lubricating film is in the range of about 1 to 10 nm. is about 1~
27. The magnetic recording disk of claim 26, in the 5 nm range. 28. A rigid nonmagnetic disk-shaped substrate, a thin magnetic recording film vacuum-deposited on the substrate, and a metal oxide, oxycarbide, or oxynitride deposited on the recording film. An overcoat film mainly composed of carbon doped with a component selected from among those that has the function of imparting affinity to the lubricant film to be deposited later, and an active group in the lubricant molecule on the overcoat film. , a hydrocarbon lubricant, and a perfluorinated lubricant. 29. The recording disk of claim 28, wherein the carbon-based overcoat film is doped in an amount of about 1 to 30% by weight with respect to the carbon-based overcoat film. . 30. The recording disk of claim 29, wherein said carbon-based overcoat film is formed by vacuum deposition from a composite target comprised of a carbon material and said selected doping component. 31. The carbon-based overcoat film is sputtered at a sputtering pressure in the range of about 5 to 20 mTorr in the presence of a sputtering gas containing about 2 to 10% hydrogen in argon. From a composite target composed of 94% graphite and about 6% tungsten, about 15%
2. Sputter deposited to a thickness of ~40 nm.
9 recording disc. 32. The recording disk of claim 31, wherein said substrate member comprises an aluminum disk coated with a non-magnetic overcoat. 33. The recording disk according to claim 32, wherein the recording film is selected from an iron-based alloy and a cobalt-based alloy. 34. The magnetic recording disk of claim 33, wherein said nonmagnetic protective film is a NiP film, and further includes a thin chromium film on the surface of said NiP film below the recording film. 35. A step of providing a vacuum-deposited thin magnetic recording film, a carbon-based alloy, and a metal oxide selected from metal oxides, oxynitrides, and oxide carbides having an affinity for lubricants. 2. A method for manufacturing a lubricated magnetic recording disk, comprising: providing a vacuum-deposited overcoat film on the recording film, and providing a lubricant film on the overcoat film. 36. The method of claim 35, comprising selecting the recording film from an iron-based alloy and a cobalt-based alloy. 37. Claim 3, wherein the lubricating film is selected from a hydrocarbon compound and a perfluoro compound.
Method 6. 38. The second material is silicon oxide.
38. The method of claim 37.