JPH0981928A - Magnetic recording medium and magnetic recorder using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To ensure low noise and to enable a high-speed recording even when a plastic having a low softening point is used as a substrate by imparting a prescribed surface roughness to a magnetic film. SOLUTION: A substrate 1 is made of surface-tempered glass, a Cr film as an under film 2, a CoCrPt film as a magnetic film 3 and a carbon film as a protective film 4 are successively formed under the same condition in film formation and then a lubricant film 11 is formed by vacuum deposition. The magnetic film 3 contains at least grains having (100) faces parallel to the film surface and a hexagonal closest-packed structure and grains having (101) faces parallel to the film surface and a hexagonal closest-packed structure. The ratio between the peak intensity of the X-ray diffraction of the grains having (100) faces parallel to the film surface and that of the grains having (101) faces parallel to the film surface is 1:0.5 to 1:5.

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 used for recording information, and more particularly to a magnetic recording medium having a low medium noise and a high recording density and a magnetic recording apparatus using the same.

[0002]

2. Description of the Related Art When the density of a magnetic disk device, which is a typical magnetic recording device, is increased, the reproduction output of a conventional electromagnetic induction type magnetic head is generally lowered and reproduction becomes difficult. For this reason, as described in JP-A-51-44917, a magnetoresistive effect is obtained in which a recording magnetic head and a reproducing magnetic head are separately provided and a high output is obtained even when the recording density is increased as a reproducing magnetic head. Use of a magnetic head of this type is under consideration. The magnetoresistive effect type magnetic head has a high reproduction output and a low head resistance, so that the thermal noise generated is small. Therefore, the noise caused by the magnetic recording medium, which has been hidden by the large noise generated from the electromagnetic induction type magnetic head, occupies a large proportion of the noise of the entire apparatus. Therefore, in order to realize a high recording density using the magnetoresistive magnetic head,
It is necessary to reduce noise (medium noise) caused by the magnetic recording medium.

In order to reduce the noise of the magnetic recording medium, it is necessary to reduce the exchange interaction between the magnetic crystal grains forming the medium. For example, a CoCrTa magnetic recording medium in which exchange interaction between crystal grains is reduced by segregating Cr, which is a non-magnetic substance, in a crystal grain boundary is known as the 18th Annual Meeting of the Japan Society for Applied Magnetic Science 14aG-9 (1994). )It is described in.

In this way, C in which Cr is segregated between crystal grains is used.
By forming oCrTa by giving magnetic anisotropy in the circumferential direction of the disk, the signal-to-noise ratio (S /
IEEE T is that a magnetic recording medium with a high N) can be obtained.
rans. Magn. , MAG-29, pp. 371
5-3717 (1993).

Further, in order to increase the density of the magnetic recording medium, it is necessary to improve the positioning accuracy of the magnetic head in the radial direction of the disk. To solve this problem, for example, a substrate having unevenness corresponding to the positioning servo signal of the magnetic head is formed by injection molding of plastics, and CoCr is formed thereon.
A magnetic recording medium on which a Pt magnetic film is formed is disclosed in Journal of Applied Magnetics Society of Japan, Vol. 17, Supplement, No. S
2, pp. 51-57, 1993.

[0006]

[Problems to be Solved by the Invention] However, the above-mentioned Proceedings of the 18th Annual Meeting of the Japan Society for Applied Magnetics 14aG-9
In the technique described in (1994), the substrate is heated to 200 ° C. to segregate Cr at the crystal grain boundaries to form a magnetic film. Therefore, the film formation process such as temperature control is complicated, and when plastics (organic resin) is used for the substrate, it is impossible to use this technique because its softening point is low.

In addition, the above-mentioned IEEE Trans. Ma
gn. , MAG-29, pp. 3715-3717 (1
In the technology described in 993), the substrate is textured in order to impart magnetic anisotropy to the CoCrTa magnetic film. However, when plastics (organic resin) or surface-strengthened glass is used for the substrate, the textured processing is extremely difficult. Have difficulty.

Further, the above-mentioned Journal of Applied Magnetics of Japan, Vol.
17, Supplement, No. S2, pp. 51
The magnetic recording medium described in −57 and 1993 has a coercive force of 1
In order to reduce the medium noise to as low as 500 Oe or less, the magnetic film has two layers, and an extremely thin Cr layer of 0.5 nm is provided between them. For example, a coercive force of 1500 Oe is insufficient to obtain a recording density of 700 Mb / in 2, and the film formation process of the magnetic film having the above structure is complicated, and it is extremely difficult to control the film thickness of the intermediate Cr layer. is there.

An object of the present invention is, for example, a magnetic recording medium having low noise and capable of high density recording even when a plastic having a low softening point is used as a substrate, and a magnetic recording apparatus using the same. To provide.

[0010]

According to the present invention, even in a magnetic recording medium in which Cr is not unevenly distributed in the crystal grain boundaries in the magnetic film, by using the magnetic film having a desired surface roughness, low noise can be achieved. To realize. That is, the magnetic recording medium has a structure in which a base film is provided between a non-magnetic substrate and a magnetic film, the difference between the Cr concentration at any position of the magnetic film and the average Cr concentration is within ± 7%, and The film has a standard length of 500 nm in the film surface direction.
In the above area, the maximum height (Rmax) is 5 nm or more, so that low noise is realized. In a magnetic recording medium in which a base film, a magnetic film, a protective film, and a lubricating film are laminated on a non-magnetic substrate in this order, the lubricating film is distributed in the cross-sectional direction of the magnetic recording medium to a thickness equal to or larger than the thickness of the protective film, or The film may be in contact with at least one of the base film and the magnetic film. All of these have a structure in which magnetic coupling between magnetic crystal grains is broken, and when a substrate without texture processing is used, that is, the coercive force in the circumferential direction in the film surface of the magnetic film and the radius A high signal-to-noise ratio is realized even when the coercive force ratio in the direction is 1.2 or less. The magnetic film is
CoCrPt or CoCrPtX (X = Ta, Mo, N
b, Zr, SiO ₂ , Si ₃ N ₄ , ZrO ₂ , SiC), and has a Cr concentration that is both magnetostatically and thermally stable at 8 at
% Or more and 20 at% or less, and the Pt concentration at which high coercive force is obtained can be 5 at% or more and 20 at% or less. Further, by setting the film thickness of the magnetic film to 10 nm or more and 50 nm or less and the product of the residual magnetization and the film thickness to 50 Gauss · um or more and 300 Gauss · um or less, noise reduction is realized while maintaining the signal strength. The magnetic film contains at least crystal grains having a hexagonal close-packed structure whose (100) plane is parallel to the film plane and crystal grains having a hexagonal close-packed structure whose (101) plane is parallel to the film plane, and (100) X of a crystal grain whose plane is parallel to the film surface and a crystal grain whose (101) plane is parallel to the film surface
Noise can be reduced by setting the peak intensity ratio of line diffraction to 1: 0.5 or more and 1: 5 or less.

The crystal orientation of the above magnetic film is Cr or CrX (X = Ti or V) for the base film, and the film thickness is 30 n.
It can be realized by setting m or more. In addition, the base film,
The (110) plane includes at least crystal grains having a body-centered cubic structure parallel to the film plane and the (200) plane includes crystal grains having a body-centered cubic structure parallel to the film plane, and the (110) plane is parallel to the film plane. X-ray diffraction peaks of crystal grains and (200) plane parallel to the film plane
When the intensity ratio is 100: 0.5 or more and 100: 15 or less, a magnetic film having a desired surface roughness can be formed thereon.

When an organic resin is used for the non-magnetic substrate, a stress relaxation layer is provided between the substrate and the underlying film to prevent cracking of the underlying film or the magnetic film, and the thermal expansion coefficient of the stress relaxation layer is By setting the coefficient of thermal expansion to be larger than, it is possible to reduce noise while preventing film cracking. Base film is Cr or CrX
(X = Ti or V), and the film thickness needs to be 200 nm or less to prevent cracking. In the stress relaxation layer,
Al or the like can be used.

The magnetic recording medium having the above structure is realized by the manufacturing method which does not include the step of heating the non-magnetic substrate.

A magnetic recording apparatus according to the present invention is realized by including at least the above magnetic recording medium, means for rotating the magnetic recording medium, and a magnetic head.

The magnetic recording medium according to the present invention has an area in which the magnetic characteristics of the magnetic film are selectively changed according to a predetermined pattern, and a signal generated when the area is scanned by the magnetic head is generated by the magnetic head. It can be a servo signal for positioning or a read-only memory signal. Further, it has a region in which the surface shape of the non-magnetic substrate is selectively changed according to a predetermined pattern, and a signal generated when the region is scanned by the magnetic head is a servo signal for magnetic head positioning or reproduction. It may be a dedicated memory signal.

A magnetic recording apparatus according to the present invention comprises the above magnetic recording medium, a means for rotating the magnetic recording medium, a magnetic head, and a servo pattern generated by a servo pattern provided on the magnetic recording medium. The position of the magnetic head can be controlled by the boh signal.

Further, the signal generated by the read-only memory pattern provided on the magnetic recording medium can be reproduced. Further, the above-mentioned magnetic recording medium can be put in a cartridge so that the cartridge can be exchanged.

[0018]

It has been found by experiments by the inventors that, for example, when Cr is formed by sputtering at room temperature under appropriate conditions, films composed of crystal grains of various orientations can be obtained.

When the underlayer film is composed of two or more kinds of crystal grains having different orientations, each growth rate is different, so that unevenness is formed on the surface of the underlayer film, and the crystal grains of the magnetic film formed on the surface of the underlayer film have a space. Separate.

Therefore, if the Cr film is used as a base film, a magnetic film composed of spatially separated crystal grains can be formed.

When the crystal grains forming the magnetic film are spatially separated, the exchange interaction between the crystal grains is weakened and the medium noise is reduced.

[0022]

The present invention will be described in detail below with reference to examples.

[Example 1] A magnetic recording medium whose cross-sectional view is shown in FIG. 1 was manufactured according to the manufacturing process shown in FIG. A direct current (DC) magnetron sputtering film forming apparatus was used for the production.

First, a sample for X-ray diffraction consisting of only a base film was prepared. A small piece of surface-strengthened glass shown in FIG. 2A is used as the substrate 1, and the ultimate vacuum is 8 × 10 ⁸ Torr, A
Under an r gas pressure of 5.5 mTorr and room temperature, 300 nm of Cr was formed as the base film 2 as shown in FIG. The X-ray-diffraction result of the produced sample is shown to Fig.3 (a). FIG.
From (a), the base film 2 has four body-centered cubic Crs with different orientations.
It can be seen that it is composed of crystal grains (Cr in Fig. 3
(110) and Cr (220) represent crystal grains having the same orientation).

Next, samples for X-ray diffraction, morphological observation and magnetic characteristic measurement of the underlayer and the magnetic film were prepared. Figure 2 on board 1
Using the small pieces of surface-strengthened glass shown in (a), under the above film forming conditions, as shown in FIGS. 2 (b)-(c), Cr is used as the base film 2 from 50 nm to 300 nm, and Co is used as the magnetic film 3.
₇₄ Cr ₁₃ Pt ₁₃ was sequentially formed in a thickness of 20 nm. FIG. 3B shows an X-ray diffraction result of a sample in which Cr is formed to a thickness of 300 nm as the base film 2. The magnetic film 3 shown in FIG.
Hexagonal close-packed CoCr whose 0) plane is parallel to the surface of the magnetic film 3.
It can be seen that the Pt crystal grains and the (101) plane are composed of hexagonal close-packed CoCrPt crystal grains parallel to the surface of the magnetic film 3. The diffraction intensity from the CoCrPt (101) plane examined for the samples of each Cr underlayer film thickness is CoCrPt.
When the diffraction intensity from the Pt (100) plane was set to 1, it was as follows. Cr Underlayer Thickness Diffraction intensity of (101) plane 50 0.5 100 0.7 200 1 300 3 500 5 Cr (20
The diffraction intensity from the (0) plane was as follows when the diffraction intensity from the Cr (110) plane was 100.

Diffraction intensity of Cr underlayer film thickness (200) plane 50 15 100 8 200 2 300 1 500 0.5 Further, the cross section of the sample in which Cr is formed to 300 nm as the underlayer film 2 in FIG. The results of observation are shown. From FIG. 4, it can be seen that the CoCrPt crystal grains forming the magnetic film 3 are grown on the Cr crystal grains forming the base film 2 which are spatially sufficiently separated. Further, from this figure, since the thickness of the magnetic film 3 is 20 nm, the maximum height (Rma
It can be seen that x) is 20 nm or more. When the magnetization curve of the sample produced using the sample vibration type magnetization measuring device was measured, the coercive force was 2450 Oe. Further, when Si and APO (amorphous poly olefin: organic resin) were used as the substrate 1 and were similarly prepared and measured, their coercive forces were 2480 Oe and 2470 Oe, respectively.

Based on the above results, FIGS. 2 (b)-(e) are shown under the same film forming conditions, using the surface-strengthened glass having a diameter of 2.5 "shown in FIG. 2 (a) as the substrate 1. As described above, Cr is sequentially formed as the base film 2 with a thickness of 300 nm, CoCrPt with a thickness of 20 nm as the magnetic film 3, and C with a thickness of 10 nm as the protective film 4.
Finally, the lubricating film 11 was formed by vacuum vapor deposition. The vacuum vapor deposition apparatus is adjacent to the sputtering film forming apparatus, and the sample is kept in a vacuum atmosphere until C is formed as the protective film 4 by the sputtering film forming apparatus until the lubricating film 11 is formed by the vacuum vapor deposition apparatus. There is. Using the magnetic recording device shown in FIG. 5, the electromagnetic conversion characteristics of the manufactured magnetic recording medium 51 were examined. The magnetic recording device is provided with a recording / reproducing separation head 53 in which an electromagnetic induction type head for recording and a magnetoresistive effect type head for reproduction are integrated. Peripheral speed 10
Noise up to a recording density of 120 kFCI was measured at a flying height of the magnetic head 53 of m / sec and a recording density of 120 kFCI was compared, and a signal-to-noise ratio (S / N) of 34 dB was obtained. A sample having CoCrPt of 15 nm as the magnetic film 3 was similarly prepared and measured, and a signal-to-noise ratio of 36 dB was obtained.

Similar results are obtained by using CrTi as the base film 2,
It was also obtained when CrV was formed. The signal-to-noise ratio (S / N) of each sample was measured using the above magnetic recording device, and the following results were obtained.

Underlayer material Signal-to-noise ratio (S / N) Cr ₈₀ V ₂₀ 34 dB Cr ₈₇ Ti ₁₃ 35 dB Similar results were obtained for the magnetic film 3 using CoCrPtT.
a, CoCrPtMo, CoCrPtNb, CoCrP
tNi, CoCrPtZr, CoCrPtSiO2, C
oCrPtSiN, CoCrPtZrO2, CoCrP
It was also obtained when tSiC was used. The signal-to-noise ratio (S / N) of each sample was measured using the above magnetic recording device, and the following results were obtained.

Magnetic Film Material Signal to Noise Ratio (S / N) (Co ₇₄ Cr ₁₃ Pt ₁₃ ) ₉₈ Ta ₂ 34 dB (Co ₇₄ Cr ₁₃ Pt ₁₃ ) ₉₇ Mo ₃ 35 dB (Co ₇₄ Cr ₁₃ Pt ₁₃ ) ₉₇ Nb ₃ 30 dB (Co ₇₄ Cr ₁₃ Pt ₁₃ ) ₉₇ Ni ₃ 32 dB (Co ₇₄ Cr ₁₃ Pt ₁₃ ) ₉₇ Zr ₃ 33 dB (Co ₇₄ Cr ₁₃ Pt ₁₃ ) ₉₄ (SiO 2) ₆ 35 dB (Co ₇₄ Cr ₁₃ Pt ₁₃ ) ₉₆ (Si ₃ N ₄ ) ₄ 34 dB (Co ₇₄ Cr ₁₃ Pt ₁₃ ) ₉₀ (ZrO 2) ₁₀ 34 dB (Co ₇₄ Cr ₁₃ Pt ₁₃ ) ₉₀ (SiC) ₁₀ 34 dB In this example, the surface-strengthened glass was used as the substrate 1.
Similar results were obtained by using, for example, a Si substrate, a surface thermal oxidation Si substrate, an APO substrate, a carbon substrate, or an Al alloy substrate having NiP formed on the surface.

Example 2 A magnetic recording medium whose plan view is shown in FIG. 6 was manufactured according to the manufacturing process shown in FIG. FIG. 6 shows only the servo pattern in a simplified manner. Some tracks have a read-only memory (RO) corresponding to the data.
M) -A pattern is formed. FIG. 8 is a sectional view of the magnetic recording medium shown in FIG.

As shown in FIG. 7B, Cr ₈₇ Ti ₁₃ of 100 nm is formed as a base film 2 on the Si substrate 1 whose surface is 2.5 ″ in diameter and is thermally oxidized as shown in FIG. After being exposed to the air, Cr was deposited to a thickness of 50 nm as the second base film 5. After that, the servo region 2 was formed by the photolithography method used in the manufacturing process of semiconductor elements and the like.
The pattern was exposed to 0 and developed, and the resist film was left in the region where the second Cr undercoat film 5 was left. Then, Cr of the second undercoat film 5 is selectively etched by 50 nm by a Freon-based reactive ion etching method, and as shown in FIG. 7C, a Cr second undercoat film having a desired pattern is formed. 5 was formed.
As a result, in the servo areas 20 provided in a spiral shape across the recording track, clock patterns 21, 22 and 22, as shown enlarged in a circle in FIG.
Servo pattern 23 and clock pattern 24,
In the area of No. 25, the second base film 5 disappeared and the base film 2 appeared on the surface. In this embodiment, the clock pattern 21,
The width of 22, 24, and 25 was 2 μm, and the servo pattern was an oval with a width of 2 μm and a length of 5 μm. However, these dimensions or numbers are merely examples and do not limit the present invention. Then, the above Cr
_{After the 87} Ti ₁₃ underlayer 2 and the second underlayer 5 made of Cr are lightly sputtered / etched, the Cr ₈₇ Ti ₁₃ underlayer 2 and the second underlayer 5 made of Cr are formed under the same film forming conditions as in FIG. As shown in (d)-(f), Co _{74 is used} as the magnetic film 3.
Cr ₁₃ Pt ₁₃ is 20 nm and carbon is used as the protective film 4.
The lubricating film 11 was finally formed at 0 nm. Using a test piece formed at the same time as the magnetic recording medium, the magnetization curves of the magnetic film 3 in the region with and without the second underlayer film 5 were measured. As indicated by the solid line, in the region where the second base film 5 is present, it is indicated by the broken line in FIG.

As described above, the magnetic characteristics of the magnetic film formed on the region where the second underlayer 5 is provided and the region where the second underlayer 5 is not provided are different. By utilizing the difference in coercive force between the two regions, the magnetic film 3 is first degaussed by a strong magnetic field, and then degaussed by a small magnetic field with a changed polarity, as shown in FIG. A magnetic domain corresponding to the presence or absence of is formed.

Therefore, as shown by the solid line in FIG. 11 (a), when the servo signal passes through the servo area while being positioned on the recording track, a detection signal as shown in FIG. 11 (b) is obtained. On the other hand, as shown by the broken line in FIG. 11 (a), when passing through the servo area in a state deviated from the recording track, the servo shown in FIG.
BO signal is generated. In the magnetic recording device, the detection signal is as shown in FIG.
The position of the magnetic head in the track width direction is controlled to position the magnetic head with respect to the magnetic recording medium based on the waveform as shown in FIG.

FIG. 12 shows a signal processing diagram of this magnetic recording apparatus. The manufactured magnetic recording medium 51 was incorporated into the magnetic recording device shown in FIG. The magnetic recording medium 51 was demagnetized twice with a DC magnetic field of which polarity and size were changed. When the recording / reproducing separation head 53 was used to reproduce at a spacing of 0.07 μm and a peripheral speed of 10 m / sec, the signal-to-noise ratio (S /
N) A positioning signal could be obtained at 30 dB. Under this condition, when a magnetic head was positioned on a track on which a read-only memory (ROM) pattern was formed and an attempt was made to reproduce the data, data corresponding to the pattern was obtained.

[Embodiment 3] FIG. 13 is a schematic sectional view corresponding to FIG. 8 of another embodiment of the magnetic recording medium according to the present invention. A schematic plan view is as shown in FIG.

In Example 2, a magnetic recording medium having a servo / signal embedded therein was prepared with or without a second underlayer.
In this example, the substrate surface was formed by forming irregularities corresponding to the servo pattern.

The substrate 1 having irregularities on its surface was produced by injection molding APO (amorphous polyolefin: organic resin). Next, on the substrate 1 at room temperature, Al is used as the stress relaxation layer 12 with a thickness of 50 nm and C as the base film 2.
r ₈₇ Ti ₁₃ is 100 nm, and Co ₇₀ Cr _{18 is used} as the magnetic film 3.
Pt ₁₂ was 20 nm, C was 10 nm as a protective film, and finally a lubricating film was sequentially formed.

The magnetic film 3 thus formed has uniform magnetic characteristics, but has irregularities as shown in FIG. Since the magnetic field generated from the magnetic head for writing has a distribution in the height (depth) direction, when a weak magnetic field is generated, the concave portion farther from the magnetic head of the magnetic recording medium is not magnetized, Only the convex portion closer to the magnetic head can be magnetized.

The magnetic recording medium thus prepared was incorporated into a cartridge of a magnetic recording device of a replaceable medium type (model: SQ3270) sold by Psychst (USA).
The electromagnetic conversion characteristics of the produced magnetic recording medium were examined by connecting the signal processing circuit shown in FIG. 12 to the magnetic recording device.

The cartridge was inserted into the magnetic recording device, demagnetized twice with a DC magnetic field having different polarities and sizes, and then the spacing was 0.07 using a recording / reproducing separation head.
Playback at um, peripheral speed 10m / sec, S / N ratio 25
The positioning signal could be obtained in dB. Under this condition, when a magnetic head was positioned on a track on which a read-only memory (ROM) pattern was formed and an attempt was made to reproduce the data, data corresponding to the pattern was obtained.

[0042]

According to the present invention, a magnetic recording medium having low noise and capable of high-density recording can be provided, and a magnetic recording apparatus using the same can be provided.

[Brief description of drawings]

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

FIG. 2 is a manufacturing process diagram of an example of a magnetic recording medium according to the present invention.

FIG. 3 is a diagram showing an X-ray diffraction result of a magnetic recording medium according to the present invention.

FIG. 4 is a schematic view of a cross section of a magnetic recording medium according to the present invention.

FIG. 5 is a schematic view of a magnetic recording device according to the present invention.

FIG. 6 is a plan view of another embodiment of the magnetic recording medium according to the present invention.

FIG. 7 is a manufacturing process drawing of another embodiment of the magnetic recording medium according to the present invention.

FIG. 8 is a sectional view of another embodiment of the magnetic recording medium according to the present invention.

FIG. 9 is a diagram showing a magnetization curve of a magnetic recording medium according to the present invention.

FIG. 10 is an explanatory diagram showing a magnetization state of the magnetic recording medium according to the present invention.

FIG. 11 is an explanatory diagram showing a servo pattern and a servo signal according to the present invention.

FIG. 12 is a signal processing diagram of the magnetic recording apparatus according to the present invention.

FIG. 13 is a sectional view of another embodiment of the magnetic recording medium according to the present invention.

[Explanation of symbols]

1 ... Substrate, 2 ... Underlayer film, 3 ... Magnetic film, 4 ... Protective film, 5 ...
Second base film, 11 ... Lubrication film, 12 ... Stress relaxation layer, 20
... servo area, 21, 22, 24, 25 ... clock pattern, 23 ... servo pattern, 51 ... magnetic recording medium, 52 ... magnetic recording medium drive section, 53 ... magnetic head, 5
4 ... Magnetic head drive unit, 55 ... Recording / reproducing signal processing system

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Masaaki Ninomoto 1-280 Higashi Koikeku, Kokubunji, Tokyo 1-280, Central Research Laboratory, Hitachi Ltd. (72) Inventor Akagi Kyo 1-280 Higashi Koikeku, Kokubunji, Tokyo Hitachi Ltd. Central Research Laboratory, Mfg. Co., Ltd. (72) Researcher Tanahashi 1-280, Higashi Koikekubo, Kokubunji City, Tokyo, Central Research Laboratory, Hitachi, Ltd.

Claims (8)

[Claims] 1. A magnetic recording medium having at least a non-magnetic substrate, a magnetic film containing at least Co and Cr, and a base film containing at least Cr provided between the substrate and the magnetic film, The magnetic film contains at least crystal grains having a hexagonal close-packed structure whose (100) plane is parallel to the film plane and crystal grains having a hexagonal close-packed structure whose (101) plane is parallel to the film plane, and (100) The crystal grain whose plane is parallel to the film plane and the above (101)
A magnetic recording medium characterized in that the peak intensity ratio of X-ray diffraction of crystal grains whose planes are parallel to the film surface is 1: 0.5 or more and 1: 5 or less. 2. The magnetic recording medium is on a disk, and the magnetic film has a ratio of a coercive force in the circumferential direction in the film surface to a coercive force in the radial direction of 1.2 or less. The magnetic recording medium according to claim 1, wherein the magnetic recording medium is a magnetic recording medium. 3. The magnetic recording medium according to claim 1, wherein the non-magnetic substrate is an organic resin, and the surface of the substrate is provided with irregularities corresponding to a servo pattern. . 4. The magnetic film is CoCrPt or CoCr.
PtX (X = Ta, Mo, Nb, Zr, SiO ₂ , Si ₃
N ₄ , ZrO ₂ , SiC) and a Cr concentration of 8 at
% Or more and 20 at% or less, and the Pt concentration is 5 at%
4. The magnetic recording medium according to claim 1, wherein the content is 20 at% or less. 5. The magnetic film having a thickness of 10 nm or more and 50 n or more.
m or less and the product of residual magnetization and film thickness is 50 Gaus
The magnetic recording medium according to any one of claims 1 to 4, wherein the magnetic recording medium has a s-um or more and 300 Gauss-um or less. 6. The base film is made of Cr or CrX (X = Ti).
Or V), and the film thickness of the base film is 30 nm or more and 200 nm or less.
The magnetic recording medium as described in any one of 1 above. 7. A magnetic recording medium comprising at least a non-magnetic substrate, a magnetic film containing at least Co and Cr, and a base film containing at least Cr provided between the substrate and the magnetic film. The formation film includes at least crystal grains having a body-centered cubic structure in which the (110) plane is parallel to the film plane and crystal grains having a body-centered cubic structure in which the (200) plane is parallel to the film plane.
The peak intensity ratio of X-ray diffraction of the crystal grains having the (10) plane parallel to the film plane and the crystal grain having the (200) plane parallel to the film plane is 100:
A magnetic recording medium, which is 0.5 or more and 100: 15 or less. 8. A magnetic recording medium comprising at least a non-magnetic substrate, a magnetic film containing at least Co and Cr, and a base film containing at least Cr provided between the substrate and the magnetic film, The magnetic film contains at least crystal grains having a hexagonal close-packed structure whose (100) plane is parallel to the film plane and crystal grains having a hexagonal close-packed structure whose (101) plane is parallel to the film plane, and (100) The crystal grain whose plane is parallel to the film plane and the above (101)
A magnetic recording medium having a peak intensity ratio of X-ray diffraction of crystal grains whose planes are parallel to the film surface of 1: 0.5 or more and 1: 5 or less, a means for rotationally driving the magnetic recording medium, and a magnetic head. And a means for controlling the position of the magnetic head by means of a servo signal generated by a servo pattern provided on the magnetic recording medium.