JPH05334644A - Magnetic recording medium - Google Patents

Abstract

PURPOSE:To increase reproduction output and recording density by forming a perpendicularly magnetizable film with a CoCrTa alloy contg. V added as a fourth element. CONSTITUTION:A CoCrTaV alloy film 2 is formed on a substrate 1 with an RF magnetron sputtering device. An NiP/Al substrate is used as the substrate 1, a composite target obtd. by combining a CoCrTaV alloy consisting of, by atom, 82% Co, 17% Cr and 1% Ta with V chips 1cm square is used as a target for the magnetic film and a carbon target is used as a target for a protective film. The perpendicular coercive force and saturation magnetization of the resulting medium are enhanced and the reproduction output and recording density are increased.

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 such as a hard magnetic disk, and more particularly to a perpendicular magnetic recording medium for ultra high recording density recording.

[0002]

2. Description of the Related Art Magnetic recording media are used in computer storage devices and are generally magnetized in the longitudinal direction of the recording media. However, this magnetization method has a limit in recording density.
Therefore, research and development have been vigorously pursued with the aim of putting perpendicular magnetic recording suitable for ultra-high recording density to practical use. The perpendicular recording method is more advantageous than the longitudinal recording method for high density recording because it has a principle property that the demagnetizing field becomes smaller and the recording magnetization is stabilized when the recording signal has a shorter wavelength, that is, when the recording density increases. .. As a medium of this recording system, a magnetic film such as CoCr and CoCrTa alloy formed by sputtering or vapor deposition has been proposed as an excellent medium (Journal of Applied Magnetics, Vol.8, No.1, 1984, 1
7p).

[0003]

However, in order to obtain a medium of higher output and higher recording density, it is necessary to improve the perpendicular coercive force and the saturation magnetization. An object of the present invention is to provide a magnetic recording medium having improved perpendicular coercive force and saturation magnetization in order to improve reproduction output and recording density.

[0004]

According to the present invention, in a magnetic recording medium having a perpendicular magnetization film formed on a substrate by a sputtering method, the perpendicular magnetization film is a CoCrTa-based alloy to which V is added as a fourth element. And a magnetic recording medium. Here, the addition amount of V is 0.1 at
% Or more and 10 at% or less is preferable.

[0005]

By including V as the fourth element in the CoCrTa film, a magnetic recording medium having a high coercive force can be obtained. At this time, the saturation magnetization also becomes large and a high output can be obtained.

[0006]

EXAMPLES Examples of the present invention will be described below.
In this example, an RF magnetron type sputtering apparatus was used to manufacture a magnetic recording medium as shown in FIG. In the figure,
Reference numeral 1 is a substrate and 2 is a CoCrTaV alloy film. The substrate 1 was a NiP / Al substrate. As the target, a composite target in which an 82Co-17Cr-1Ta (at%) alloy and a V chip (1 cm square) were combined was used for the magnetic film, and a carbon target was used for the protective film. Table 1
Details of film forming conditions are shown in FIG.

[0007]

[Table 1]

First, various CoCrTaV alloy films (1500 angstroms) were formed by changing the number of V chips placed on the CoCrTa alloy target and changing the amount of V added. FIG. 2 shows the change in coercive force (Hc⊥) with respect to the amount of V added. The composition was analyzed by EPMA, and the magnetic characteristics were measured by VSM. as a result,
It can be seen from FIG. 2 that when the amount of V added is 0.1 at% or more and 10 at% or less, the coercive force is higher than that of the CoCrTa film. FIG. 3 shows changes in saturation magnetization (Ms) with respect to the amount of V added. From this, the V addition amount is 0.1 at% or more, 1
It can be seen that at 0 at% or less, the saturation magnetization becomes larger than that of the CoCrTa film.

Next, the recording / reproducing characteristics of the medium of the present invention will be described. The medium used here is Co containing 2 at% of V.
A CrTaV film (1500 Å) and carbon (200 Å) are formed as a protective film (medium A). In addition, for comparison, CoCr was used on the same substrate.
A conventional medium having a Ta alloy film (1500 Å) was also prepared (medium B). Table 2 shows the magnetic properties of these media.

[0010]

[Table 2]

FIG. 4 shows the results of comparing the R / W characteristics of the medium A of the present invention and the conventional medium B with a thin film magnetic head. From this, it is understood that the medium of the present invention has improved reproduction output and recording density as compared with the conventional medium.

[0012]

As described above, according to the present invention, the perpendicular coercive force and the saturation magnetization of the medium are increased, and the reproduction output and the recording density are improved.

[Brief description of drawings]

FIG. 1 is a sectional view of a magnetic recording medium of the present invention.

FIG. 2 is a diagram showing the dependency of coercive force on the amount of V added to the CoCrTa film in terms of magnetic characteristics.

FIG. 3 is a diagram showing the dependency of saturation magnetization on the amount of V added to a CoCrTa film in terms of magnetic characteristics.

FIG. 4 is a diagram showing recording density characteristics of a medium of the present invention in comparison with a conventional medium.

[Explanation of symbols]

 1 substrate 2 CoCrTaV alloy film

Claims (2)

[Claims] 1. A magnetic recording medium having a perpendicularly magnetized film formed on a substrate by a sputtering method, wherein the perpendicularly magnetized film is a CoCrTa-based alloy to which V is added as a fourth element. Medium. 2. The amount of V added is 0.1 at% or more, 10a
The magnetic recording medium according to claim 1, wherein the magnetic recording medium is t% or less.