JPH06231441A - Magnetic recording medium and its production - Google Patents

Abstract

PURPOSE:To improve corrosion resistance, durability, sliding resistance, recording and reproducing characteristics, error preventing characteristics, and the device life of a magnetic recording medium and a magnetic recording device (especially a system with a magnetic head having magnetoresistance effect element) using a metal magnetic thin film. CONSTITUTION:A Co-Fe-Ni alloy magnetic layer 13 is formed directly on a nonmagnetic substrate 11 or with a base coating layer 12 interposed. Further, at least one nonmagnetic thin film 14 and a protective layer 16 are formed thereon to constitute the magnetic recording medium. The protective layer consists of a distribution layer and a small part 15 essentialy consisting of a nonmagneitc material substantially different from the nonmagneitc thin film. Thereby, the obtd. magnetic recording medium is excellent in corrosion resistance, durability, sliding resistance, recording and reproducing characteristics, and error preventing characteristics, and a small-size large-capacity magnetic recording device having high reliability is obtd.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic recording medium and a method for producing the same, more specifically, a magnetic recording having a magnetic layer of a metal magnetic thin film medium used in a magnetic disk device, a magnetic card device and the like. The present invention relates to a medium and a manufacturing method thereof, and particularly to a magnetic recording medium which is suitable for high density, small size and large capacity, and has excellent reliability, and a manufacturing method thereof.

[0002]

2. Description of the Related Art In order to increase the capacity and size of a magnetic storage device, a magnetic recording medium capable of high density recording / reproduction has been developed. A magnetic recording medium using a metal magnetic thin film is suitable for high density recording because it has higher coercive force and saturation magnetic flux density than a coating type magnetic recording medium. However, since the magnetic recording medium using the metal magnetic thin film has a smooth surface, when the head slider and the surface of the magnetic recording medium come into contact with each other, the attraction force and the friction force are large. Conventionally, in order to reduce the attraction force and the frictional force, improve the characteristics at the time of contact start stop (CSS) at the time of starting the apparatus, and suppress the abrasion and damage of the magnetic head and the disk surface, the conventional document jar is used. As disclosed in Null of Applied Physics, Vol. 55, p. 2254 (1984), in a magnetic disk, fine irregularities called texture are formed on the surface of a substrate along substantially the circumferential direction, or in Japanese Patent Laid-Open Publication No. 9-58242. Kaihei 2-23051
As disclosed in No. 0, a coating type medium in which a filler is dispersed is simulated, and fine clusters containing Fe, W, WC and the like having a diameter of about 0.5 μm are formed in a substantially amorphous carbon protective film. A technique has been proposed in which the carbon protective film is dispersed so as to protrude from the surface of the carbon protective film by about 60 nm.

[0003]

Recently, demands for higher recording density, lower cost and smaller size of magnetic storage devices are extremely strong, and it is possible to set the distance between the magnetic head and the magnetic recording medium to about 100 nm or less. It's needed. When fine irregularities called texture are formed on the surface of the medium substrate as in the above literature, it is necessary to make the height of the convex portion as small as possible. However, if CSS is repeated,
There is a problem that the convex portion is easily worn and the surface is easily smoothed, and the frictional force is increased. In the medium of the type proposed in the above-mentioned Japanese Patent Laid-Open Publication, in which fine clusters are dispersed so as to protrude from the surface of the protective film by about 60 nm,
Since it is difficult to accurately control the size, height, and frequency of occurrence of the cluster protrusions, it is difficult to obtain excellent durability against friction and stable characteristics during recording and reproduction. As described above, according to the conventional technology, it is possible to stably provide a thin film magnetic recording medium which is excellent in sliding resistance and recording / reproducing characteristics and suitable for high recording density, and a small-sized and large-capacity magnetic storage device using the thin-film magnetic recording medium. It's getting harder.

A main object of the present invention is to realize a magnetic recording medium excellent in sliding resistance and recording / reproducing characteristics and suitable for high recording density, and a small-sized and large-capacity magnetic storage device using the same. Is. Another object of the present invention is to realize a method for manufacturing a magnetic recording medium which is excellent in sliding resistance and recording / reproducing characteristics and is suitable for high recording density.

[0005]

In order to achieve the above object, the present invention provides a magnetic recording medium in which a magnetic layer of a metal magnetic thin film and a protective layer are sequentially laminated directly on a substrate or via an underlayer. A protective layer, at least one non-magnetic thin film made of a non-magnetic material, and a distribution layer of a minute portion which is formed on the non-magnetic thin film and has a main constituent of a non-magnetic material different from the material of the non-magnetic thin film. To form. Further, in order to form the protective layer of the magnetic recording medium of the present invention, after forming a plurality of non-magnetic thin films of at least two kinds which are substantially different from each other on the magnetic layer of the metal magnetic thin film, fine and substantially uniform holes are formed. Etching is carried out using a mask in which is distributed, depending on the physical effect, the chemical effect, or the combined effect of both,
At least the uppermost nonmagnetic thin film of the plurality of nonmagnetic thin films is substantially removed, leaving substantially the small portion covered with the mask to form a distribution layer of the small portion.

In a preferred embodiment, the thickness of the distribution layer of the minute portion, that is, the average height of the minute portion is 1 nm or more and 30 nm or less. The distribution layer of the minute portion may be made of one kind of material, or depending on the material, at least partly made of two or more kinds of materials. Further, the minute portion is made of carbon such as amorphous carbon or iC, or at least H, N, O, B, W, Mo,
It is composed of a carbonaceous material whose main component is carbon containing one of Nb and Ta, and even more desirably, the lowermost layer of the plurality of non-magnetic thin films has a higher resistance than the carbonaceous material of the minute portion. quality, or WC, MoC, carbides such as _{W-MoC, ZrO 2, SiO} 2, Al 2 O 3 oxide such, Z
It is composed of a nitride such as r-Nb-N or W-Zr-N.

[0007]

In the magnetic recording medium of the present invention, the protective layer is mainly composed of at least one nonmagnetic thin film and a nonmagnetic material formed on the nonmagnetic thin film and substantially different from the material of the nonmagnetic thin film. By forming unevenness on the protective layer by using it as an element and etching using a mask, the height, size, and distribution of the unevenness formed on the protective layer can be set to an optimum state, so that durability is improved. It is possible to realize a thin film magnetic recording medium which is strong in slipperiness, has excellent sliding reliability, recording / reproducing characteristics, etc. and is suitable for high recording density, and a small-sized and large-capacity magnetic storage device using the same.

In particular, the minute portion of the distribution layer is made of amorphous carbon, carbon such as iC, or at least H, N,
When carbon containing any one of O, B, W, Mo, Nb, and Ta is used as a main component, high hardness and lubricity peculiar to carbonaceous material can be utilized. The contact area with the magnetic head is suppressed, and the wear of the protrusions
Further, the dust generation rate can be reduced, and excellent adhesive force and frictional force can be maintained even when CSS and the like are repeated.

Further, the lowermost layer of the plurality of non-magnetic thin films is made of carbonaceous material having higher resistance (lower density or higher coverage) than the material of the distribution layer of the minute portion, or WC, MoC, W-Mo.
When a carbide such as —C, an oxide such as ZrO ₂ , SiO ₂ , Al ₂ O _3, or a nitride such as Zr—Nb—N or W—Zr—N is used, Co, Fe, and Ni are the main components. Since the alloy magnetic layer has high coverage and has high resistance, it is possible to prevent corrosion current and protect the metal magnetic thin film layer with a cheap high resistance layer,
In particular, the effect is remarkable when the magnetic head of the magnetic recording device has a reproducing portion by the magnetoresistive effect.

Further, in the production of the magnetic recording medium of the present invention, at least two nonmagnetic thin films made of different materials are formed as the protective layer, and then a mask is used to perform a physical etching effect by Ar, nitrogen ions, etc., oxygen. , The chemical etching effect of fluorine ions or the like, or the combined effect of both, substantially removes at least the uppermost thin film while leaving the minute portion covered by the mask substantially, and the distribution layer of the minute portion is formed. It has been found that the best reliability is obtained when formed.

This is because the etching surface is smoothed and modified by etching, or different protective film materials are diffused, and the main surface of the protective film has a specific surface area larger than that in the case where a single layer film is simply formed. It was found that the corrosion resistance and the durability were remarkably improved due to the small size, water repellency and high hardness. This effect is remarkable in complex etching. Further, according to the method of manufacturing a magnetic recording medium of the present invention, a minute portion can be formed on the protective layer directly or through the high-adhesion ultrathin layer with good adhesion, and the true contact area with the magnetic head is 50%. Since it can be reliably controlled to be less than 10%, and more preferably about 10% or less, the initial adhesive force and frictional force can be reduced as compared with the conventional magnetic recording medium.

If the average height of the minute portion is 1 nm or more, the durability required for CSS can be secured, and if it is 30 nm or less, the distance between the head and the medium can be kept small, so that high recording / reproducing characteristics can be secured. . This effect can be recognized when the area ratio of the protrusions is 0.5% or more.
% Or more, the initial tangential force is large. When it is 10% or less, the effect of improving the practical durability is high, but this can be changed according to the required life.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. <Embodiment 1> FIG. 1 is a partial sectional view showing the structure of an embodiment of a magnetic recording medium according to the present invention. In the figure, 11
Is Al-Mg alloy plated with Ni-P, glass, S
Non-magnetic substrate such as i, C and Ti, 12 and 12 'are Cr and M
a non-magnetic underlayer made of o, W, Cr-Ti, Ge, etc., 1
3, 13 'are CoCrTa, CoCrPt, SmC
Co, F made of CoNiCr, FeCoNi, etc.
e, a single magnetic layer composed of an alloy magnetic thin film of a magnetic material containing Ni as a main component, or the above magnetic material and Cr, M
Magnetic layers of multi-layer metal magnetic film consisting of at least two metal magnetic layers laminated via non-magnetic intermediate layers such as o, W, CrTi, C, B, Si and Ge, 14, 14 ′, 15, 1
5'is a protective film composed of a plurality of non-magnetic thin films, which is a feature of the present invention, and the distribution layers 15, 15 'in the minute portion are made of carbon or H, N, O, B, W, Mo, Nb, A non-magnetic (carbonaceous) material containing carbon as a main component containing any one of Ta, and the bottom layers 14 and 14 ′ are distribution layers 15 and 1 of a minute portion.
Higher resistance than 5'material (low density or high coverage)
Carbonaceous, or WC, MoC, carbides such as _{W-MoC, ZrO 2, SiO} 2, Al 2 O 3 oxide such, Zr-N
It is a nitride such as b-N or W-Zr-N. 16, 16 '
Is a lubricating film made of perfluoroalkylpolyether or the like.

In addition to the above combinations, the alloys of the magnetic layers 13 and 13 'may further include Cr, Mo, W, V, Nb, Ta, and
Pt, Ir, B, Y, Zr, Hf, O, N, C, Al,
At least one of Si and Ge is 0.1 at% or more 30
By containing at% or less, segregation of non-magnetic substances in the magnetic crystal grains and at grain boundaries can be promoted, magnetic interaction between crystal grains can be reduced, and medium noise can be reduced. Underlayer 1 here
Providing 2, 12 'can promote heteroepitaxial growth and crystal orientation of the magnetic layers 13, 13' so as to be suitable for high-density recording, and further enhance the adhesion to the substrate 11.
To improve the adhesion, Cr, Mo, W, Ti, Nb, T
a or a non-magnetic alloy containing these as main components is chemically active, has high lattice matching with the magnetic layer, and is highly effective.

Specific examples will be described in more detail below. Al-4 with an outer diameter of 95 mm and a thickness of 0.89 mm
Ni on both sides of the disk substrate 11 made of Mg (wt%).
A 10 μm-thickness plating layer made of −12 P (wt%) was formed. The surface of the non-magnetic substrate 11 was smooth-polished until the centerline average roughness Ra became 0.5 nm or less, and then a texture having a centerline surface roughness of 3 nm was formed along the substantially circumferential direction. The substrate thus processed was loaded into a magnetron sputtering device, and the temperature was 200 ° C. and the argon gas pressure was 2 m.
Torr, C with a power of 5 W / cm ² and a film thickness of 100 nm
Nonmagnetic underlayers 12 and 12 ′ made of r, and a magnetic film 1 made of Co-10Cr-4Ta (atomic%) having a thickness of 35 nm.
3 and 13 'were sequentially formed.

Subsequently, in an argon gas containing 10% by volume of hydrogen on the magnetic film, the gas pressure was 3 mTorr and the input power was 5 W.
Hydrogen-containing carbon protective film 1 with a film thickness of 15 nm at 1 / cm ²
4 and 14 'were formed, and a 15 nm amorphous carbon protective film was further formed using pure argon gas at a gas pressure of 2 mTorr and an input power of 7 W / cm ² . Further, a mask having a diameter of about 5 μm and an area ratio of 5% is placed on the surface, and plasma ashing is performed by changing the etching time with oxygen containing 10% by volume of nitrogen. A distribution layer of the protrusions 15 was formed. Finally, on the composite protective film, that is, the protective films 14, 14 '.
Lubricating layers 16, 16 'of adsorbable perfluoroalkyl polyether were formed on the exposed surface and the minute projections 15 to obtain a magnetic disk as a magnetic recording medium.

For comparison, a magnetic disk having minute protrusions with heights of 14, 15 and 16 nm formed by the same treatment after forming a hydrogen-containing carbon protective film or carbon protective film having a film thickness of 30 nm alone. did. Environmental tests and abrasion tests were performed on these magnetic disks to compare the characteristics. As an environmental test, a constant temperature and humidity test was performed for 1 month under the conditions of a temperature of 80 ° C. and a relative humidity of 90%.
When the characteristics were evaluated using a composite type magnetic head having a magnetoresistive effect element of .mu.m, it was found that in a magnetic disk having a protective film formed of carbon or hydrogen-containing carbon alone, 100 protrusions and 50 protrusions were obtained at any protrusion height. An increase of more than one error was observed. However, in the magnetic disk of this example, although an increase of several errors was observed when the 14 nm fine protrusion was formed,
No increase in error was observed in the magnetic disk having 16 nm fine protrusions. The electric resistance of the hydrogen-containing carbon layer was about 10 times that of the carbon layer.

Next, as a durability test with the magnetic head, a CSS test was conducted 50,000 times with the above-mentioned head, and as a result, in any of the magnetic disks of this embodiment, damage to the disk,
No increase in tangential force or adhesive force was observed, whereas in the magnetic disk of Comparative Example having a protective film consisting of carbon and hydrogen-containing carbon alone, the disk was damaged and the tangential force and adhesive force were 10 respectively. , Increased by more than 20 grams. As described above, only this example satisfied the corrosion resistance, the durability, and the sliding resistance at the same time. This is because the etching surface is smoothed and modified by etching, and hydrogen diffusion occurs at the interface, so the main surface of the protective film has a small specific surface area, is highly water-repellent, and has high hardness, so it has corrosion resistance and durability. It is because it is remarkably improved. Further, the same examination was carried out on a magnetic disk in which the order of forming the carbon protective film and the hydrogen-containing carbon protective film was exchanged, and it was confirmed that the magnetic disk exhibited excellent characteristics as compared with the comparative example. However, in this case,
The highest corrosion resistance was exhibited when the fine protrusions of 14 nm were formed.

For the embodiment of the above magnetic disk, C
No error was found due to abnormal discharge, contact, etc. during SS or during signal reproduction, but with the conventional structure, an error frequently occurred after 10,000 CSS repetitions. Under the recording condition of 400 megabits per square inch, the device S / N was as high as 3.5 in all cases.

The magnetic layer is made of CoCrPt, CoNiCr, C
oNiPt, CoCrPt / Cr / CoCrTa multilayer film, underlayer Mo, W, CrTi alloy, CrSi alloy,
The bottom layer of the protective film is WC, SiC, WZrC, SiO ₂ , Ytria-added ZrO ₂ , Al ₂ O ₃ film, and the top layer of the protective film contains 5 at% of H, N, O, B, W, Mo, Nb, and Ta. The same effect was observed when the same treatment was performed using a carbonaceous film. Further, the same effect was obtained by etching with an ion beam method or a reverse sputtering method with argon, nitrogen, oxygen or the like.

<Embodiment 2> FIG. 2 is a partial sectional view of another embodiment of the magnetic recording medium according to the present invention. In the figure, 21 is an Al-Mg alloy plated with Ni-P or the like, glass, a non-magnetic substrate of Si, C, Ti or the like, and 23 and 23 'are CoPt, CoCrPt, SmCo, CoNiPt, F.
A single layer of eCoNi, FeCoCr, CoCrTa, or the like, or the above magnetic material and Cr, Mo, W, C, B, Si,
Multi-layer metal magnetic film made of Ge or the like, 24, 24 ', 25,
25 'is a composite non-magnetic protective film, which is a feature of the present invention, 2
Reference numerals 6 and 26 'are lubricating films made of perfluoroalkylpolyether or the like. Each layer 21, 21 ', 2 of this embodiment
3, 23 ', 24, 24', 25, 25 ', 26, 2
6'is 11, 11 ', 13, 13', 14, 1 in FIG.
4 ', 15, 15' and 16, 16 ', which are substantially the same as those of the embodiment of FIG.

Further specific examples will be described below.

Al with an outer diameter of 130 mm and a thickness of 1.9 mm
-Ni on both sides of the disk substrate made of -4Mg (wt%)
A plating layer having a film thickness of 20 μm and made of −13P (wt%) was formed. This non-magnetic substrate 21 is provided with a center line average roughness Ra
To 0.4 nm or less, and further, a texture having a centerline surface roughness of 1 nm was formed along the substantially circumferential direction. The substrate treated in this way is then subjected to an oblique ion beam.
It was loaded into a sputtering system and the film thickness was 1 at 300 ° C.
5 nm Co-10Cr-4Pt (atomic%), film thickness 3n
m of C and 15 nm of film thickness of Co-10Cr-4Pt (atomic%) were sequentially formed at an incident angle of about 70 degrees to form a multilayer magnetic film. Further, methane gas was used on the magnetic film by the plasma CVD method at a gas pressure of 30 mTorr and a film thickness of i-C of 10 nm.
A protective film is formed, followed by a pure argon gas and a gas pressure of 2
A 10 nm amorphous carbon protective film was formed with mTorr.

Next, a mask having a diameter of about 2 μm and an area ratio of 2% was set on the surface, and plasma etching was performed with oxygen gas containing 30% by volume of CF ₄ , and the height was 9, 10, 11 nm.
Micro-protrusions substantially composed of amorphous carbon were formed. Finally, an adsorbent perfluoroalkyl polyether lubricating layer was formed on the composite protective film to obtain a magnetic disk. For comparison, a magnetic disk having a 20 nm-thickness i-C protective film and an amorphous carbon protective film formed thereon and subjected to the same treatment was also manufactured as a prototype. These magnetic disks were subjected to a constant temperature and constant humidity test for two months under the conditions of a temperature of 60 ° C. and a relative humidity of 95%, and evaluated with a composite type magnetic head having a magnetoresistive effect element with a track width of 3 μm. In the magnetic disk of No. 3, an increase in the number of errors of 50 or more was recognized, but in this example, the increase in the error was not recognized at all. The electric resistance of the i-C layer is about 50 compared with the carbon layer.
It was double.

Next, a CSS test was performed 20,000 times as a wear test with the magnetic head. As a result, no damage was observed on the disk surface or no increase in tangential force or adhesive force was found in the magnetic disk of this example. On the other hand, in the case of the magnetic disk of i-C and carbon alone protective film, damage was observed on the disk surface,
Furthermore, the tangential force and the adhesive force each increased by 10 grams or more. As described above, only this example satisfied the corrosion resistance, the durability, and the sliding resistance at the same time. In this medium, the device S / N is 3.0 when the device condition is 500 megabits per square inch.
Met.

The magnetic layer is made of FeCoCr, CoTa, Fe.
C, CoPt, CoNiPt single layer film, FeCoCr / T
a / FeCoCr multilayer film, the bottom layer of the protective film is 15 nm N
bC, TaC, WMoC, ZrO _{2 with} alumina added, H, N, O, B, W, Mo, Nb, Ta as the uppermost layer of the protective film is 1
The same effect was observed when the carbonaceous material containing 5 at% was formed to a thickness of 5 nm and the same treatment was performed.

<Embodiment 3> FIG. 3 is a block diagram of an embodiment of a magnetic memory device according to the present invention. (A) And (b) shows a plane schematic diagram and a sectional view, respectively. In this embodiment, 1 to 10 magnetic recording media of Embodiment 1 or 2 are incorporated. In this embodiment, a disk-shaped magnetic recording medium 31, a drive unit 32 for rotating and driving the same, a composite magnetic head 33 having a reproducing element unit by a magnetoresistive effect and its driving means 34, and recording / reproducing of the magnetic head. This is a magnetic storage device having a well-known configuration including a processing means 35. As a result, by combining with a composite magnetic head having an element having a magnetoresistive effect as a reproducing portion, a recording density of 400 to 500 megabits per square inch can be realized, and further, error due to abnormal discharge or the like does not occur. The magnetic head with a mean time between failures (abbreviated as MTBF) of 10,000 hours or more has a long life, and a small-sized and large-capacity magnetic storage device having excellent reliability can be realized. This is because the composite protective film has a very high substantial electrical resistance when the magnetic head is in contact with it, compared to the conventional magnetic recording medium using a uniform amorphous carbon as a protective film. This is because the abnormal discharge of the flowing current can be remarkably suppressed, the occurrence of the error due to the discharge peculiar to the magnetoresistive effect element is small, and the damage of the magnetic head element part can be suppressed.

Although the embodiments have been described above, the present invention is
The invention is not limited to the above embodiment. For example, the magnetic thin film may be formed of at least two metal magnetic layers that are laminated by suppressing interaction with each other through a non-magnetic intermediate layer. Since the medium noise generated from the two metal magnetic layers is statistically averaged, the total medium noise can be reduced.
In particular, high S / N can be realized by recording / reproducing with a composite magnetic head having a reproducing portion having a magnetoresistive effect.

[0029]

According to the present invention, a magnetic layer containing Co, Fe and Ni as main components and a protective layer are sequentially laminated directly on a non-magnetic substrate or via an underlayer, and at least one protective layer is formed. Metal magnetic thin film magnetic recording is made by substantially comprising a non-magnetic thin film and a minute portion which is placed on the non-magnetic thin film and has a non-magnetic material which is substantially different from the non-magnetic thin film as a main component. It is possible to provide a metal magnetic thin film magnetic recording medium having excellent environment resistance, abrasion resistance, and high recording density characteristics in combination with the high density recording characteristics of the medium, and a small-sized large-capacity magnetic storage device using the same.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional view showing the structure of one embodiment of a magnetic recording medium according to the present invention.

FIG. 2 is a partial cross-sectional view showing the structure of another embodiment of the magnetic recording medium according to the present invention.

3A and 3B are views showing the structure of a magnetic memory device according to one embodiment of the present invention, and FIGS. 3A and 3B are a schematic plan view and a sectional view taken along line AA of FIG. 3A, respectively.

[Explanation of symbols]

 11, 21 ... Disk substrate, 12, 12 '... Underlayer, 13, 13', 23, 23 '... Magnetic layer, 14, 14', 24, 24 '... Composite protective layer, 15, 15', 25, 25 '... Distribution layer of minute portion 16, 16', 26, 26 '... Lubrication layer, 31 ... Magnetic recording medium, 32 ... Magnetic recording medium drive unit, 33 ... Magnetic head, 34 ... Magnetic head drive unit, 35 ... Recording / reproducing Signal processing system

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yasuo Yaku 1-280, Higashi Koikekubo, Kokubunji, Tokyo Inside Central Research Laboratory, Hitachi, Ltd. (72) Inventor Akira Ozaki 1-280 Higashi Koikeku, Kokubunji, Tokyo Hitachi Ltd. (72) Inventor Tomio Yamamoto 1-280, Higashi Koikeku, Kokubunji, Tokyo Metropolitan Institute, Hitachi Ltd. (72) Masatoshi Takeshita 1-280, Higashi Koikeku, Kokubunji, Tokyo Hitachi Central Lab. (72) Inventor Masaaki Matsumoto 1-280 Higashi Koigokubo, Kokubunji City, Tokyo Inside Hitachi Central Research Laboratory

Claims (8)

[Claims] 1. A magnetic recording medium in which a magnetic layer of a metal magnetic thin film and a protective layer are sequentially laminated on a substrate or via an underlayer, wherein the protective layer is a nonmagnetic thin film made of a nonmagnetic material, A magnetic recording medium comprising: a distribution layer of a minute portion formed on the non-magnetic thin film, the main component being a non-magnetic material different from the material of the non-magnetic thin film. 2. The magnetic recording medium according to claim 1, wherein the non-magnetic material of the distribution layer of the minute portion is carbon or any one of H, N, O, B, W, Mo, Nb and Ta. A magnetic recording medium containing carbon as a main component. 3. The magnetic recording medium according to claim 1 or 2, wherein the non-magnetic material of the non-magnetic thin film has a higher resistance than the non-magnetic material of the distribution layer of the minute portion. Magnetic recording medium. 4. The magnetic recording medium according to claim 1, 2 or 3, wherein the average height of the minute portions is 1 nm or more and 30 nm.
A magnetic recording medium characterized by the following: 5. The magnetic recording medium according to claim 1, 2, 3 or 4, wherein the magnetic layer of the metal magnetic thin film is Co, Fe,
A magnetic recording medium comprising a magnetic layer containing Ni as a main component. 6. The magnetic recording medium according to claim 1, 2, 3 or 4, wherein the magnetic layer of the metal magnetic thin film comprises at least two metal magnetic layers stacked with a non-magnetic intermediate layer interposed therebetween. A magnetic recording medium characterized by: 7. A magnetic recording medium, a magnetic head for recording and reproducing, a means for making relative movement with respect to the magnetic head and the magnetic recording medium, a signal input to the magnetic head and an output signal from the magnetic head. 7. A magnetic storage device having a recording / reproducing signal processing means for reproducing, wherein the magnetic head has a reproducing element portion by a magnetoresistive effect, and the magnetic recording medium is the magnetic recording medium according to claim 1. A magnetic storage device comprising a medium. 8. A step of forming a magnetic layer of a metal magnetic thin film directly on a non-magnetic substrate or via an underlayer, and a first non-magnetic thin film layer made of a first non-magnetic material on the magnetic layer. And a step of forming the first non-magnetic thin film layer on the first non-magnetic thin film layer.
A step of laminating a thin film layer of a second non-magnetic material different from the non-magnetic material, and etching the thin film of the second non-magnetic material through a mask to make the thin film of the second non-magnetic material fine. A method of manufacturing a magnetic recording medium, comprising the step of forming a partial distribution layer.