JPS61190715A - Magnetic recording body - Google Patents

Abstract

PURPOSE:To improve the coercive force of the titled recording body by forming the magnetic metallic film of the magnetic recording body which is formed on the surface of a nonmagnetic base material through a Cr film with a Co-V-Ni alloy of specified composition. CONSTITUTION:A Cr film is formed on the surface of a nonmagnetic base material and a magnetic metallic film is formed on the upper surface of the Cr film to obtain a magnetic recording body. The magnetic metallic film is formed with CoxVyNiz and the ratio of the components is regulated to 0.45<=x<1.0, 0<y<=0.20 and x+y+z=1. Consequently, the coercive force can be remarkably improved, the size of the Cr film can be sharply reduced when a magnetic recording body having the same coercive force as the conventional Co magnetic film and Co-Ni magnetic film is produced, hence the consumption of a target is decreased and the productivity can be improved. Moreover, a magnetic recording body having extremely improved corrosion resistance in comparison with conventional magnetic recording bodies can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a magnetic recording medium used in a longitudinal recording type hard disk medium or the like.

(Prior art) In the past, metal 779 film type magnetic recording bodies have attracted attention as media capable of high-density recording and are beginning to be put into practical use. There is a magnetic recording body formed by forming a Co film by sputtering or vapor deposition. This magnetic recording body exhibits a high coercive force in the in-plane direction, and is being applied to in-plane recording type hard disk media and the like.

Also, recently, instead of the Co film which is the magnetic film of the recording medium,
Co-Mill is known.

(Problems to be Solved by the Invention) As described above, in a magnetic recording body in which a CO magnetic film is formed through a Cr film formed on a non-magnetic base material surface, as the thickness of the Cr1l increases, the coercive force decreases. increases, but its coercive force is 60
To obtain a film of about 0 to 80008, the film thickness should be 400
0 to 8,000 people, and if you try to produce it using sputtering or vapor deposition, the Cr film will be 400
Since it is necessary to increase the thickness of 0 to 8,000 people, there are problems such as large consumption of targets and relatively slow production speed. Therefore, even if the Cr film thickness is made thinner, the
0 e, in other words, 400
It is desired to manufacture a magnetic recording medium having a coercive force higher than the above with 0 to 8000 people. On the other hand, magnetic recording bodies in which the magnetic film is a Co film have a drawback of poor corrosion resistance. In order to solve the above problems, a magnetic recording body using a Co--Ni magnetic film instead of the CO magnetic film has improved coercive force and improved corrosion resistance. That is, the Cr film thickness is 70 for 3000 people.
A coercive force of 0.00 e is obtained, but in order to obtain the same coercive force, it is more preferable if the Cr film can be made thinner, and it is even more preferable if the corrosion resistance of the magnetic film is further improved.

(Means for Solving the Problems) The present invention provides a magnetic recording medium that satisfies the above-mentioned requirements. In the recording body, the magnetic metal film is C
It is expressed as oxVyN i z and 0.45 ≦X〈
10, O<y≦0.20, x+y+z=1.

(Example) Next, examples of the present invention will be described.

The inventor added V to CO and Co-Ni, respectively, as a magnetic film.
Co-V with various composition ratios by changing the addition 111m of
Magnetic recording bodies were formed in which a magnetic film and a Co-V-1 magnetic film were formed on a Cr film surface formed on a non-magnetic base material surface, and the coercive force and corrosion resistance of each were examined.

In Figures 1 and 2, the Cr film thickness is 3000, and the Co -
(2) The relationship between the change in the blending ratio of the binary or ternary alloy components and the coercive force of the magnetic recording material that was tested by 500 people is also shown.

As shown in curve A for the Co-V magnetic film and curve B for the Co-V-1 magnetic film in Figure 1, in both cases, when the addition amount of It can be seen that the coercive force increases. In particular, in a magnetic film made of a Co-V-Ni ternary alloy, the highest coercive force of 8000 e was obtained with an addition of about 108 t%, and this value is the highest among the conventionally known ones shown as a control in the figure. Co0.7 indicating coercive force
Best coercivity cuff of Ni0.31itl film 000e
It turns out that you can get something better than that. Also, as shown in the first diagram, the coercive force of a magnetic film made of Co alone is 4000.
In contrast, according to the present invention, as is clear from FIG. The range is CoxVyNiz, where 0.45≦x<
10, O<y≦0.201x+y+z=1.

Most preferable region C: Co0.60 V'0.10 N
i is around 0.30.

Figure 3 shows the Co0.60V O,10 old 0.301i magnetic film, the CoO,7NiO,3 magnetic film, and the CO single magnetic film, respectively, with the thickness of the Cr film formed on the non-magnetic base material surface being changed. The results of examining the relationship with coercive force when

As is clear from this figure, the same coercive force, e.g. 700
In order to obtain 0 e, the Cr film thickness needs to be 5000 people in the case of CoVitl magnetic film, and the Cr film thickness needs 3000 people in the case of the Co-Ni magnetic film.
In the case of an o-V-Hill type membrane, it is found that a thickness of 2000 people is sufficient. Furthermore, C of the present invention.

-V-Ni magnetic film is Co-di magnetic film and CO! Compared to a monomorphic film, a film with improved coercive force can be obtained regardless of the change in the thickness of the Cr film, regardless of the thickness at any point.

Moreover, the corrosion resistance of the Co-V-Ni magnetic film of the present invention is
FIG. 4 shows the results of testing with an O-only magnetic film and a CoNi magnetic film. The corrosion resistance test was evaluated by the decrease in saturated fO magnetization under the conditions of constant temperature and humidity of 60° C. and 90%. As is clear from FIG. 4, it can be seen that the corrosion resistance of the magnetic film t of the present invention is significantly increased.

In manufacturing the magnetic film of the present invention, trace amounts of other elements may be added. Further, any wear-resistant or corrosion-resistant organic or silent protective film may be formed on the upper surface of the magnetic film thus prepared.

In the method for manufacturing a magnetic recording body of the present invention, the Cr film on the non-magnetic base material surface is formed by a sputtering method, a vapor deposition method, etc.
A Co-V magnetic film or a CO-V-Ni magnetic film can be formed on the top surface of the film by sputtering or vapor deposition, but since the vapor pressures of Co, old, and V are different, the sputtering method is preferable. , easy to manufacture. It is preferable that the time from the formation of the Cr film to the formation of the magnetic film be as short as possible.

The manufacturing conditions for the magnetic recording medium of the present invention by the OC magnetron sputtering method are, for example, as follows.

Substrate plated glass, substrate once twice room temperature, ultimate vacuum:
Less than 8x10' L~-L, Ar gas pressure during sputtering: 1x1O'Torr, Magnetic 1 sample thickness: 500 people constant, Cr film deposition rate: 1000 people/mn, Magnetic film:
500 people/I, Targera] - Distance between boards: 10
08. Changes in the composition of Co, V, and Ni in the magnetic film are CO
Sputtering was performed by placing V or Ni chips on the target. The composition analysis of the produced magnetic film was determined using a fluorescent X-ray method.

(Effects of the Invention) As described above, the present invention provides C
The magnetic metal film of a magnetic recording body formed by forming a magnetic metal film on the upper surface of an r film is made of CoxVyN i z and the proportion ratio of these components is 0.45≦X<1.
．． 0, Q<y≦0.20, x+y+z
-1, so in order to significantly improve the coercive force and to produce a magnetic recording medium that has the same coercive force as that of conventional Co magnetic films and Co-Ni magnetic films, the Cr film must be significantly reduced. As a result, it is possible to reduce the amount of target consumption, improve productivity, and obtain a magnetic recording body with significantly improved corrosion resistance compared to the conventional magnetic recording bodies described above.

[Brief explanation of drawings]

Fig. 1 is a graph showing the relationship between the component composition and coercive force of the magnetic film of an example of the present invention, Fig. 2 is a triangular diagram showing the same relationship, and Fig. 3 is a graph showing the relationship between Cr film thickness and coercive force. The graph shown in FIG. 4 is a graph showing the relationship between changes in the composition of the magnetic film and corrosion resistance. (Oe)

Claims (1)

[Claims] In a magnetic recording body formed by forming a magnetic metal film on a non-magnetic base material surface via a Cr film, the magnetic metal film is made of CoxVy
Niz and 0.45≦x<1.0, 0<y≦
0.20, x+y+z=1 atomic % composition ratio.