JPH06309647A - Magnetic recording medium and its production - Google Patents

Abstract

PURPOSE:To produce a magnetic recording medium having >=2,200Oe coercive force Hc. CONSTITUTION:A magnetic film 2 of a Co-Cr-Ta-Pt quaternary alloy is formed on a glass substrate 5 with an underlayer 3 of Cr and a precoat film 4 to obtain a magnetic disk 1. In this disk 1, the X-ray diffraction intensities of Cr (200) and Co (110) as lattice faces of Cr and Co crystals are lower than those of Cr (200) and Co (110) preferentially oriented parallel to the surface of the glass substrate.

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 using a glass substrate, and more particularly to a magnetic recording medium suitable for high density recording having a high coercive force Hc.

[0002]

2. Description of the Related Art Recently, magnetic recording media capable of high-density recording have been sought, and therefore, efforts have been made to develop magnetic recording media having higher coercive force Hc. In the field of magnetic disks, sputter disks, which are conventionally coated disks but are compatible with high density recording, are becoming the mainstream.

The magnetic disk of the above-mentioned sputter type has a Cr underlayer and a Co-Ni film on an Al substrate which is initially plated with NiP.
Alternatively, a Co-Ni-Cr magnetic film is provided in this order, and a carbon film and a lubricating layer are provided on this magnetic film. With the increase in recording density, a glass substrate that can reduce the flying height of the head has appeared, and low noise Co-Cr-Ta and Co-Cr-Pt have been developed for magnetic films.

In order to further increase the coercive force Hc, for example, Japanese Patent Application Laid-Open No. 1-256017 discloses Co-Cr-Ta.
A technique using a magnetic layer of -Pt is described, and
Japanese Patent Publication No. 4-50653 discloses a bias sputtering technique for forming a film while applying a negative bias voltage.

[0005]

However, in any of the above-mentioned techniques, when the glass substrate excellent in the low flying height characteristic is used, the high magnetic property of the coercive force Hc exceeds 2200 (Oe). No discs have been obtained. An object of the present invention is to provide a magnetic recording medium having a coercive force Hc of 2200 (Oe) or more and a method for manufacturing the same.

[0006]

In order to solve the above problems, in the magnetic recording medium of the present invention, the lattice planes of the Cr crystal and the Co crystal in the magnetic film are the lattice planes of the Cr crystal, Cr (200) and Co crystal. In comparison with the X-ray diffraction intensity in the case where the lattice planes Co (110) of the both are preferentially oriented parallel to the glass substrate surface,
The X-ray diffraction intensities of r (200) and Co (110) are low.

In the manufacturing method of the present invention, the precoat film is formed of a material containing at least one of V, Mo, and NiP, and the underlayer film and the magnetic film are sputtered while applying a negative bias voltage. It is formed by the method.

[0008]

In the magnetic recording medium of the present invention, the relative positions of the lattice planes of the growing Cr crystals and Co crystals and the glass substrate surface are adjusted by controlling the film forming conditions of the precoat film, the base film and the magnetic film. The coercive force Hc is improved.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. Here, FIG. 1 is a partial sectional view showing an example of a magnetic disk according to the present invention. This magnetic disk 1 is C
The magnetic film 2 made of a quaternary alloy of o-Cr-Ta-Pt is
It is formed on the glass substrate 5 on which the base film 3 made of and the precoat film 4 are provided. To use it as the magnetic disk 1, a carbon lubricating layer (not shown) is placed on the magnetic film 2, and a lubricant is further applied thereon.

In the magnetic film 2, the lattice planes of the Cr crystal (body-centered cubic crystal) and the Co crystal (hexagonal crystal) are Cr.
Crystal lattice plane Cr (200) and Co crystal lattice plane Co
Compared with the X-ray diffraction intensity when both (110) are preferentially oriented parallel to the glass substrate surface, Cr (200) and Co
The X-ray diffraction intensity of (110) is low. Similarly, the X-ray diffraction intensity of Cr (110) is high.
The magnetic disk 1 according to the present invention having such a lattice plane has a coercive force Hc of 2200 (Oe) or more, and can even exceed 3200 (Oe).

The above contents will be specifically described. FIG. 9 is a conceptual diagram showing a unit cell of a Cr crystal and a Co crystal in the magnetic film 2 in which the conventional Cr (200) and Co (110) are preferentially oriented parallel to the glass substrate surface. In the X-ray diffraction by the 2θ / θ method, the X-rays are diffracted only from the lattice plane parallel to the surface of the glass substrate 5, so that in FIG. 9, these Cr (200) and Co (110) The diffraction intensity is strong.

However, as described above, when Cr (200) and Co (110) are preferentially oriented parallel to the surface of the glass substrate 5, as shown in FIG. Is no longer parallel to. Therefore, this Cr (1
The diffraction intensity of 10) decreases.

FIG. 2 is a conceptual diagram showing a unit cell of a Cr crystal of the magnetic film 2 in which Cr (110) according to the present invention is preferentially oriented parallel to the glass substrate surface. This FIG. 2 and the above FIG.
As is clear from the comparison of Cr (11
The diffraction intensity of 0) is stronger than in the case of FIG. on the other hand,
FIG. 3 shows Cr (200) and Co (11) according to the present invention.
0), the diffraction intensities of Cr (200) and Co (110) in FIG. 3 are weaker than in the case of FIG. 9, as is clear from comparison with FIG.

That is, C in the magnetic film 2 according to the present invention.
The X-ray diffraction intensities of r (200) and Co (110) are I _{Cr (200)} and I _{Co (110)} , respectively.
When the X-ray diffraction intensities of (200) and Co (110) are I _{0Cr (200)} and I _{0Co (110)} , respectively, (I _{Cr (200)}
/ I _{0Cr (200)} ) <1, but preferably (I _{Cr (200)} /
I _{0Cr (200)} ) ≦ 0.4. Also (I _{Co (110)} / I
_{0Co (110)} ) <1, but preferably (I _{Co (110)} / I
_{0Co (110)} ) ≦ 0.6.

Further, Cr in the magnetic film 2 according to the present invention is
The X-ray diffraction intensity of ₍₁₁₀₎ is I _{Cr (110),} and
The X-ray diffraction intensity of Cr (110) at 0 is I _{0Cr (110)}
Then, (I _{Cr (110)} / I _{0Cr (110)} )> 1 is _satisfied, but (I _{Cr (110)} / I _{0Cr ( 110 )} ) ≧ 1.35 is preferable.

Next, an example of a method of manufacturing the magnetic disk 1 according to the present invention will be described. Most importantly, as described above, the preferentially oriented planes of the Cr and Co crystals in the magnetic film 2 change. There is no limitation on any manufacturing method as long as it can cause the change of the orientation plane.

FIG. 4 is a schematic view showing an example of the sputtering apparatus according to the present invention. In the figure, the sputtering apparatus 6 is provided with a target 8 and a magnetic disk holder 9 in a vacuum layer 7, and is provided with an inlet 10 for an inert gas such as Ar and a vacuum exhaust port 11. A DC power supply 12 for sputtering is connected to the target 8, and a DC power supply 13 for bias is connected to the magnetic disk holder 9.
Are connected.

In order to manufacture the magnetic disk 1 according to the present invention by using the sputtering apparatus 6, first, a precoat film which has already been formed by a sputtering method or the like with a material containing at least one of V, Mo and NiP. Glass substrate 5 with membrane 4
Is attached to the magnetic disk holder 9. Then, after evacuating from the vacuum exhaust port 11, from the inlet port 10 to, for example, A
An r gas is introduced, and a DC voltage is applied by the DC power supply 12 for sputtering and a DC power supply 13 for bias.

As described above, when the Cr base film 3 or the Co-Cr-Ta-Pt quaternary alloy magnetic film 2 is formed on the glass substrate 5 with the precoat film 4 while applying a negative bias voltage, Glass substrate 5 flying from the target 8
Some of the atoms such as Cr adhering to are sputtered under the influence of a negative bias voltage to cause the change of the preferential orientation plane, and have the lattice plane according to the present invention, and the coercive force Hc2.
The magnetic disk 1 of 200 (Oe) or more can be used.

Next, examples according to the present invention will be described in more detail. Example 1 On a 3.5-inch glass substrate 5, a precoat film 4 of V was formed by 60 Å by a DC magnetron method. The film-forming conditions at this time are that the ultimate vacuum is 2 × 10 ⁻⁶ Tor.
r, Ar sputter gas pressure is 2 mTorr, glass substrate 5
The heating temperature was 200 ° C. After the precoat film 4 was formed, the glass substrate 5 was cooled and removed from the vacuum device.

Next, the glass substrate 5 with the precoat film 4 was attached to the magnetic disk holder 9 of the sputtering apparatus 6, and the base film 3 made of Cr was applied to the glass substrate 5 while applying a bias voltage of -200 V to 4000 liters. Co _75.2 Cr _9.4 Ta on the _5.7 Pt _{9 .7} magnetic film 2 quaternary alloy having the composition (each numerical value accompanying the atoms are at%) 2
A 50 Å film was formed to obtain a magnetic disk 1. The film forming conditions at this time are as follows: ultimate vacuum of 2 × 10 ⁻⁶ Torr, Ar sputtering gas pressure of 2 mTorr, and glass substrate 5 heating temperature of 2
It was set to 50 ° C.

For comparison with this example, a magnetic disk 1 (R-1) was prepared in the same manner as in the above manufacturing method except that a bias voltage was not applied. Then, the crystal orientation of the magnetic film 2 of Examples 1 and R-1 was measured by an X-ray diffractometer, and the magnetic characteristics (coercive force Hc) were measured by a vibrating sample magnetometer (VSM).

The results for the obtained magnetic disk 1 are shown in FIGS. 5, 7 and 8. FIG. 5 is a measurement chart of the X-ray diffraction intensity, showing the magnetic film 2 of the present embodiment in comparison with R-1.
The strength of Cr (200) and Co (110) becomes low,
The strength of Cr (110) was high. FIG. 7 is a bias voltage-coercive force Hc diagram. The coercive force Hc of the magnetic disk 1 of R-1 is 2100 (Oe), whereas that of this embodiment is as high as 3060 (Oe). It was

Further, FIG. 8 shows X-ray diffraction intensity ratio-coercive force H.
It is a c diagram, and A to C in the figure represent the following contents. In addition,
I in the following is the X-ray diffraction intensity of the magnetic film 2 of each example, I0
Is the X-ray diffraction intensity of the magnetic film 2 for comparison. A: X-ray diffraction intensity ratio of _{Cr (200)} ; A = _{ICr (200)}
/ I _{0Cr (200)} B ... X-ray diffraction intensity ratio of _{Co (110)} ; B = I _{Co (110)}
/ I 0 _{Co (110)} C ... X-ray diffraction intensity ratio of _{Cr (110)} ; C = I _{Cr (110)}
/ I _{0Cr (110) As} shown in FIG. 8, the above-mentioned A of the magnetic film 2 according to the present example was 0.08, B was 0.16, and C was 2.77 _{(note that the magnetic property of} R-1 is R-1). Membrane 2 is 1 for both A, B, and C).

Examples 2 to 4 The bias voltage applied to the glass substrate 5 of Example 1 is -1.
00V (Example 2), -300V (Example 3), -40
Magnetic disks 1 were manufactured in the same manner as in Example 1 except that 0 V (Example 4) was used instead.

These results are also shown in FIGS. 5, 7 and 8. In FIG. 5, each of the magnetic films 2 of this embodiment is R-.
As compared with 1, the strengths of Cr (200) and Co (110) are lower and the strength of Cr (110) is higher. Further, as shown in FIG. 7, the coercive force Hc of each of Examples 2 to 4 is 2450 (Oe), 3100 (Oe),
It was as high as 2800 (Oe).

Further, in FIG. 8, the above-mentioned A of the magnetic film 2 according to Examples 2 to 4 is 0.15, 0.03, respectively.
0.07, B was 0.26, 0.13, 0.26, and C was 2.81, 2.93, 1.38.

Example 5 A magnetic disk 1 was manufactured in the same manner as in Example 1 except that the thickness of the underlayer film 3 in Example 1 was changed to 1000Å. The coercive force Hc of this magnetic disk 1 was 2300 (Oe). A magnetic disk 1 (R-2) for comparison was also prepared without applying a bias voltage, but the coercive force Hc was 14
It was as low as 00 (Oe).

FIG. 6 is a measurement chart of the X-ray diffraction intensity according to this example, in which the intensity of Cr (200) and Co (110) is lower than that of R-2.

Example 6 The same as Example 1 except that a Cr film 500Å, a carbon film 500Å, and a Mo film 60Å were formed in this order in place of the V precoat film 4 of Example 1 to form the precoat film 4. Magnetic disk 1 was manufactured. The coercive force Hc of this magnetic disk 1 was 3230 (Oe). Further, the magnetic disk for comparison 1 (R-
3) was also created, but this coercive force Hc is 2150 (Oe)
Was low.

Comparative Example 1 A Cr film 60Å was formed in place of the V precoat film 4 of Example 1, and was continuously taken out without removing it from the vacuum apparatus.
A magnetic disk 1 was manufactured in the same manner as in Example 1 except that the underlayer film 3 made of Cr was deposited to 2000 Å while applying a bias voltage of 200 V. The coercive force Hc was 20.
It was as low as 50 (Oe).

As is clear from the above results, in the magnetic disk 1 according to the present invention formed by applying a negative bias voltage, all of R-1 to R- formed without applying a negative bias voltage. Coercive force H higher than that of magnetic disk 1 of 3
have c. Further, there is a peak of the coercive force Hc in the vicinity of the bias voltage of -300 V, and the magnetic film 2 of about 3100 (Oe) can be obtained. Further, as shown in Example 7 of Table 1, the coercive force H can be changed by changing the type of the precoat film 4.
The magnetic film 2 having a very high performance of c3230 (Oe) was also obtained.

As is apparent from FIGS. 5 and 6, R-1 and R- formed without applying a negative bias.
In the magnetic film 2 of No. 2, Cr (200) and Co (110) are preferentially oriented parallel to the glass substrate 5, but the magnetic films 2 of the respective examples to which a negative bias is applied are Cr (200) and Co (110).
The crystal orientation of (110) with respect to the glass substrate surface is lowered, and Cr (110) tends to be preferentially oriented parallel to the glass substrate 5.

[0034]

As described above, according to the present invention, the crystal orientation of Cr (200) and Co (110) with respect to the glass substrate surface is reduced and the lattice plane of Cr (110) is preferentially parallel to the glass substrate surface. Since it is oriented, it is a magnetic recording medium capable of high-density recording with a very high coercive force Hc.

Further, in the manufacturing method of the present invention, the precoat film is formed of a material containing at least one of V, Mo and NiP, and the base film and the magnetic film are further applied with a negative bias voltage. Since it is formed by the sputtering method, the lattice plane of Cr (110) can be preferentially oriented parallel to the glass substrate surface, and a magnetic recording medium capable of high density recording can be obtained.

[Brief description of drawings]

FIG. 1 is a partial sectional view showing an example of a magnetic disk according to the present invention.

FIG. 2 is a conceptual diagram showing a unit cell of a Cr crystal of a magnetic film in which Cr (110) according to the present invention is preferentially oriented parallel to a glass substrate surface.

FIG. 3 shows Cr (200) and Co (11) according to the present invention.
0) Conceptual diagram showing orientation

FIG. 4 is a schematic view showing an example of a sputtering apparatus according to the present invention.

FIG. 5 is a measurement chart of X-ray diffraction intensities of Examples 1 to 4.

FIG. 6 is a measurement chart of X-ray diffraction intensity of Example 5.

7 is a bias voltage-coercive force Hc diagram of Examples 1 to 4. FIG.

8 is an X-ray diffraction intensity ratio-coercive force Hc diagram of Examples 1 to 4. FIG.

FIG. 9 is a conceptual diagram showing a unit cell of a Cr crystal and a Co crystal related to a magnetic film in which conventional Cr (200) and Co (110) are preferentially oriented parallel to the glass substrate surface.

FIG. 10 is a conceptual diagram showing the orientation of conventional Cr (110).

[Explanation of symbols]

1 ... Magnetic recording medium (magnetic disk), 2 ... Magnetic film, 3 ...
Base film, 4 ... Precoat film, 5 ... Glass substrate, 6 ... Sputtering device, 7 ... Vacuum layer, 8 ... Target, 9 ... Magnetic disk holder, 12 ... Sputtering DC power supply, 13 ... Biasing DC power supply.

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[Procedure amendment]

[Submission date] July 25, 1994

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] Claim 1

[Correction method] Change

[Correction content]

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0006

[Correction method] Change

[Correction content]

[0006]

In order to solve the above problems, the magnetic recording medium of the present invention has a Cr crystal lattice plane Cr.
The X-ray diffraction intensities of Cr (200) and Co (110) are compared with the X-ray diffraction intensities when both the lattice plane Co (110) of (200) and the Co crystal are preferentially oriented parallel to the glass substrate surface. It's low.

[Procedure 3]

[Document name to be amended] Statement

[Correction target item name] 0010

[Correction method] Change

[Correction content]

Then, Cr crystal (body centered cubic crystal) and Co
The lattice plane of the crystal (hexagonal) is the lattice plane of the Cr crystal Cr (2
00) and the lattice plane Co (110) of the Co crystal are preferentially oriented parallel to the glass substrate surface, the X-ray diffraction intensity of Cr (200) and Co (110) is low. Has become. Similarly, the X-ray diffraction intensity of Cr (110) is high. The magnetic disk 1 according to the present invention having such a lattice plane has a coercive force Hc of 22.
It is possible to be more than 00 (Oe) and even more than 3200 (Oe).

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0011

[Correction method] Change

[Correction content]

The above contents will be specifically described. FIG. 9 is a conceptual diagram showing a unit cell of a Cr crystal and a Co crystal in which conventional Cr (200) and Co (110) are preferentially oriented parallel to the glass substrate surface. In the X-ray diffraction by the 2θ / θ method, since the X-rays are diffracted only from the lattice plane parallel to the surface of the glass substrate 5, in FIG.
The diffraction intensity of (200) and Co (110) is strong.

[Procedure Amendment 5]

[Document name to be amended] Statement

[Correction target item name] 0013

[Correction method] Change

[Correction content]

FIG. 2 is a conceptual diagram showing a unit cell of Cr crystals of the underlayer 3 in which Cr (110) according to the present invention is preferentially oriented parallel to the glass substrate surface. This FIG. 2 and the above FIG.
As is clear from the comparison of Cr (11)
The diffraction intensity of 0) is stronger than in the case of FIG. on the other hand,
FIG. 3 shows Cr (200) and Co (11) according to the present invention.
0), the diffraction intensities of Cr (200) and Co (110) in FIG. 3 are weaker than those in FIG. 9 as is clear from comparison with FIG.

[Procedure correction 6]

[Document name to be amended] Statement

[Correction target item name] 0014

[Correction method] Change

[Correction content]

That is, C in the base film 3 according to the present invention
The X-ray diffraction intensities of r (200) and Co (110) in the magnetic film 2 are I _{Cr (200)} and I _{Co (110)} , respectively, and the X-rays of Cr (200) and Co (110) in FIG. When the diffraction intensities are I _{OCr ( 200 )} and I _{OCo (110)} , respectively, (I _{Cr (200)} / I _{OCr (200)} ) <1, but preferably (I _{Cr (200)} / I _{OCr (200)} ) ≦ 0.4. Further, (I _{Co (110)} / I _{OCo ( 110)} ) <1, but (I _{Co (110)} / I _{OCo (110)} ) ≦ 0.6 is preferable.

[Procedure Amendment 7]

[Document name to be amended] Statement

[Name of item to be corrected] 0015

[Correction method] Change

[Correction content]

Further, Cr in the underlayer film 3 according to the present invention is
The X-ray diffraction intensity of _{(110 )} is I _{Cr (110 )}
The X-ray diffraction intensity of Cr (110) at 0 is I _{OCr (110)}
Then, (I _{Cr (110)} / I _{OCr (110)} )> 1, and preferably (I _{Cr (110)} / I _{OCr (110)} ) ≧ 1.35.
Is.

[Procedure Amendment 8]

[Document name to be amended] Statement

[Correction target item name] 0016

[Correction method] Change

[Correction content]

Next, an example of a method of manufacturing the magnetic disk 1 according to the present invention will be described. As described above, the preferentially oriented planes of Cr in the underlayer 3 and Co crystals in the magnetic layer 2 are changed. Is the most important, and there is no limitation on any manufacturing method as long as it can cause the change of the orientation plane.

[Procedure Amendment 9]

[Document name to be amended] Statement

[Name of item to be corrected] 0023

[Correction method] Change

[Correction content]

The results for the obtained magnetic disk 1 are shown in FIGS. 5, 7 and 8. FIG. 5 is a measurement chart of the X-ray diffraction intensity. In the magnetic disk 1 of this example, the intensity of Cr (200) and Co (110) was lower than that of R-1, and the intensity of Cr (110) was lower. It was getting higher. FIG. 7 is a bias voltage-coercive force Hc diagram, where R-
The coercive force Hc of the magnetic disk 1 of No. 1 was 2100 (Oe), while that of this example was as high as 3060 (Oe).

[Procedure Amendment 10]

[Document name to be amended] Statement

[Name of item to be corrected] 0024

[Correction method] Change

[Correction content]

Further, FIG. 8 shows X-ray diffraction intensity ratio-coercive force H.
It is a c-line diagram, and AC in the figure represents the following contents. In addition,
In the following, I is the X-ray diffraction intensity of the magnetic disk 1 of each example, and IO is the X-ray diffraction intensity of the comparative magnetic disk 1. A: X-ray diffraction intensity ratio of Cr (200); A = I
_{Cr (200)} / I _{OCr (200)} B ... X-ray diffraction intensity ratio of Co (110); B = I
_{Co (110)} / I _{OCo (110)} C ... X-ray diffraction intensity ratio of Cr (110); C = I
_{Cr (110)} / I _{OCr (110) As} shown in FIG. 8, the above-mentioned A of the magnetic disk 1 according to this example was 0.08, B was 0.16, and C was 2.77 (note that R is R). The magnetic disk 1 of -1 has A, B, and C of 1).

[Procedure Amendment 11]

[Document name to be amended] Statement

[Correction target item name] 0026

[Correction method] Change

[Correction content]

These results are also shown in FIGS. 5, 7 and 8. In FIG. 5, in the magnetic disk 1 of this example, Cr (200) and Co (110) are both compared with R-1.
The strength of Cr is low and that of Cr (110) is high. Further, as shown in FIG. 7, the coercive force Hc of each of Examples 2 to 4 is 2450 (Oe) and 3100, respectively.
(Oe) and 2800 (Oe) were high.

[Procedure Amendment 12]

[Document name to be amended] Statement

[Name of item to be corrected] 0027

[Correction method] Change

[Correction content]

Further, in FIG. 8, the above-mentioned A of the magnetic disk 1 according to Examples 2 to 4 is 0.15 and 0.0, respectively.
3, 0.07, B is 0.26, 0.13, 0.26, C
Was 2.81, 2.93, 1.38.

[Procedure Amendment 13]

[Document name to be amended] Statement

[Name of item to be corrected] 0032

[Correction method] Change

[Correction content]

As is clear from the above results, in the magnetic disk 1 according to the present invention formed by applying a negative bias voltage, all of R-1 to R- formed without applying a negative bias voltage. Coercive force H higher than that of magnetic disk 1 of 3
have c. Further, there is a peak of the coercive force Hc in the vicinity of the bias voltage of -300V, and the magnetic disk 1 of about 3100 (Oe) can be obtained. Further, as shown in Example 6, the coercive force H is changed by changing the type of the precoat film 4.
The magnetic disk 1 having a very high performance of c3230 (Oe) is also obtained.

[Procedure Amendment 14]

[Document name to be amended] Statement

[Correction target item name] 0033

[Correction method] Change

[Correction content]

As is apparent from FIGS. 5 and 6, R-1 and R- formed without applying a negative bias.
The magnetic disk 1 of No. 2 has Cr (200) and Co (11
0) is preferentially oriented in parallel to the glass substrate 5, but the magnetic disk 1 of each embodiment to which a negative bias is applied is made of Cr.
The crystal orientation of (200), Co (110) with respect to the glass substrate surface is lowered, and Cr (110) tends to be preferentially oriented parallel to the glass substrate 5.

[Procedure Amendment 15]

[Document name to be amended] Statement

[Name of item to be corrected] Figure 2

[Correction method] Change

[Correction content]

FIG. 2 is a conceptual diagram showing a unit cell of Cr crystal of a base film in which Cr (110) according to the present invention is preferentially oriented parallel to the glass substrate surface.

[Procedure Amendment 16]

[Document name to be amended] Statement

[Correction target item name] Figure 9

[Correction method] Change

[Correction content]

FIG. 9 is a conceptual diagram showing a unit cell of Cr crystal and Co crystal in which conventional Cr (200) and Co (110) are preferentially oriented parallel to the glass substrate surface.

Claims (2)

[Claims] 1. A precoat film is formed on a glass substrate, and a base film made of Cr and a Co film are formed on the precoat film.
In a magnetic recording medium in which a magnetic film made of a quaternary alloy of -Cr-Ta-Pt is formed in this order, in this magnetic recording medium, the lattice planes of the Cr crystal and the Co crystal in the magnetic film are C
L-crystal lattice plane Cr (200) and Co-crystal lattice plane Co
Compared with the X-ray diffraction intensity when both (110) are preferentially oriented parallel to the glass substrate surface, Cr (200) and Co
A magnetic recording medium having a low (110) X-ray diffraction intensity. 2. A precoat film is formed on a glass substrate,
An underlayer of Cr and Co-C are formed on the precoat film.
In a method of manufacturing a magnetic recording medium in which a magnetic film made of a quaternary alloy of r-Ta-Pt is formed in this order, the precoat film is formed of a material containing at least one of V, Mo and NiP. A method of manufacturing a magnetic recording medium, comprising forming a film, and further forming the base film and the magnetic film by a sputtering method while applying a negative bias voltage.