JPS61190713A - 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-Si- Ni alloy of specified composition. CONSTITUTION:A Cr film is formed on the surface of a nonmagnetic substrate and a magnetic metallic film is formed on the upper surface of the Cr film to obtain a magnetic recording body. The magnetic film is formed with CoxSiyNiz. The ratio of the components is regulated to 0.45<=x<1.0, 0<y<=0.15 and x+y+z=1. Consequently, the coercive force is remarkably improved, the size of the Cr film can be sharply reduced when a magnetic recording body having the same coercive force as conventional Co magnetic films and the Co-Ni magnetic film is produced, the consumption of a target can also be reduced, the productivity is improved and a recording body having improved corrosion resistance is 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 thin film 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,
A Co--Ni film is known.

(Problems to be Solved by the Invention) As described above, a magnetic recording body in which a CO magnetic film is formed through a Cr film formed on a non-magnetic base material surface has a coercive force when the thickness of the Cr film is increased. increases, but its coercive force is 600
To obtain a film of ~80,008, the film thickness must be 4,000.
〜8,000 people, and if we try to mass-produce using sputtering or vapor deposition, the film thickness of ``C'' must be 4,000〜
Since it is necessary to increase the number of people to 8,000, there are problems such as large target consumption and relatively slow production speed. Therefore, even if the Cr film thickness is made thinner, the
In other words, you can get something like 4000~
It is desired that 8,000 people produce a magnetic recording medium with a coercive force greater than the above. 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 Co11 film can be obtained which has improved retention force and corrosion resistance. That is, the Cr film thickness is 70 for 3000 people.
Although a coercive force of 008 can be obtained, 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 can be 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
oxSiyNiz and 0.45≦x<1.0
, O<y≦0.15, and X+y+z=1.

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

The inventor added S to Co and Co-Ni, respectively, as a magnetic film.
Co-3 with various composition ratios by changing the added fim of i
Magnetic recording bodies were formed in which an i magnetic film and a Co-3Co-3i- 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 -
3i or Co-3Co-3i-characteristic film thickness is kept constant at 500. The relationship between changes in the blending ratio of the binary or ternary alloy components and the coercive force of the magnetic recording body is shown.

Curve A and Co-3i-N of Co-3i magnetic film in Fig. 1
As shown in curve B of the i magnetic film, in both cases, Si
It can be seen that when the amount of Co added is up to about 15 at %, the coercive force increases compared to a magnetic film containing only Co. In particular, Co-8i-Hi
The maximum coercive force of the ternary alloy magnetic film is approximately 108t.
% addition, 78008 was obtained, and this value shows the highest coercive force among the conventionally known ones shown as a control in the figure.
o0.7 Ni0.3 ii Magnetic film best coercive cuff 00
It can be seen that an excellent value higher than 0 e can be obtained. Also, as shown in Figure 1, the coercive force of a magnetic film made of Co alone is 4.
000 e, according to the present invention, as is clear from FIG. 2, the coercive force of the present invention is higher than 4000 e. The composition range is CoxSiyNiz 1 but 0,4
5≦X×1.0, O<y≦0.15, X+V+Z=1
It is.

The most preferred region is Co0.60SiO, 10Ni
It is around 0.30.

Figure 3 shows the Co0.60 SiO, 10Ni0.30 magnetic film, the Co0.7 Hio, 31itl film, and the Co single magnetic film, respectively, as a contrast, with the thickness of the C film formed on the non-magnetic substrate surface being varied. 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, a Co6tl film requires a Cr film thickness of 5,000 layers, and a Co-Ni film requires a Cr film thickness of 3,000 layers.
In the case of a -3i-Hil film, it can be seen that a thickness of 2000 people is sufficient. Furthermore, Co-3i-N of the present invention
It4i film is Co-H1la film and rj Col
Compared to a magnetic 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-3i-Ni magnetic film of the present invention is
FIG. 4 shows the results of testing both the Co magnetic film alone and the CoNi magnetic film. The corrosion resistance test was evaluated based on the decrease in saturation 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 magnetic film of the present invention has significantly increased corrosion resistance.

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 inorganic protective film may be formed on the upper surface of the magnetic film thus prepared.

In the manufacturing method of the magnetic recording body of the present invention, the Cr film on the surface of the non-magnetic base material is formed by a sputtering method, a vapor deposition method, etc.
A Co-3il film or a C0-3i-1 magnetic film can be formed on the top surface of the film by sputtering, vapor deposition, etc.
Since the vapor pressures of C01Ni and Si are different, the sputtering method is preferable and 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.

For example, the manufacturing conditions for the magnetic recording body of the present invention by the DC magnet 1-ron sputtering method are as follows.

Substrate varnished glass, substrate temperature: room temperature, ultimate vacuum:
8X10' Torr or less, Ar gas pressure during sputtering:
lX10-2 toll, magnetic film thickness: 500 people constant, C
r film deposition rate: 1000 people/l, magnetic film = 500 people/l
mn, distance between target and substrate: 100 m, Co and Si of the magnetic film, and previous composition changes were performed by placing a Si or Hi chip on a CO target and performing sputtering.

The composition analysis of the produced magnetic film was determined using a fluorescent X-ray method.

(Effect of the invention) As described above, according to the present invention, C
rl! The magnetic metal film of the magnetic recording body is formed by forming a magnetic metal film on the upper surface of a magnetic recording body formed with C0X5iyNiZ, and the proportion ratio of these components is 045≦x.
<1.0. 0<y≦0.15,
Since x + y + Z = 1, the coercive force can be significantly improved, and in order to manufacture a magnetic recording body with the same coercive force as that of conventional Co magnetic films and Co-Ni magnetic films, the Cr1il must be significantly reduced. Since it is possible to reduce the amount of corrosion of the target, it is possible to reduce the consumption of the target, improve productivity, and obtain a magnetic recording body with significantly improved corrosion resistance compared to the conventional magnetic recording bodies mentioned 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. 2 outsiders 4 Eijoki (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 CoxSi
yNiz and 0.45≦x<1.0, 0<y
A magnetic recording body characterized by having an atomic % composition ratio of ≦0.15 and x+y+z=1.