JPH01176327A - Production of perpendicular magnetic recording medium - Google Patents

Abstract

PURPOSE:To improve the crystallinity and uniformity of a perpendicularly magnetized film by allowing already an ion implanted layer at a saturation level on the surface of a high-polymer film at the time of ion plating. CONSTITUTION:The low-energy ion implanted layer 2 is formed on the high- polymer film 1 consisting of polyethylene terephthalate or the like. Ions of the elements to be used for the perpendicular magnetic film are implanted thereto. The perpendicular magnetic film 3 consisting of Co-Cr, Co-Cr-Nb, etc., formed by an ion plating method such as high-frequency ion plating method is then formed and a protective lubricating agent layer 4 is provided. Since the ions having energy are eventually consumed for surface transfer, the crystal growth is improved and the defects are decreased; in addition, the crystallinity and uniformity of the perpendicular magnetic film are improved.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method for manufacturing a perpendicular magnetic recording medium suitable for high-density magnetic recording.

Conventional technology There has been remarkable progress in increasing the density of magnetic recording in recent years.
There are high hopes for the practical application of magnetic recording media that use ferromagnetic metal thin films as magnetic recording layers.
IE TR1NSACTIONS ON MAGNXT
IC8).

VOJ, MAG-21, NO, a, 1217-1220
(1985)].

Among these, perpendicular magnetic recording, in which demagnetization loss becomes more advantageous as the wavelength becomes shorter, requires a special film that can be magnetized in a direction perpendicular to the film surface, but efforts are still being made to put it into practical use.

The magnetic recording medium for perpendicular magnetic recording is Go-Cr.

A perpendicularly magnetizable anisotropic film made of Go-0r-Nb, Co-Ni-0, etc. is formed directly on the polymer film or via an underlayer such as 〒i, Go, etc. In the laboratory, thin films are formed by sputtering. However, as is well known, the sputtering method is not suitable for manufacturing perpendicular magnetic recording media such as magnetic tapes due to its slow thin film formation rate, and the characteristics are not necessarily satisfactory. etc. have great potential for speeding up, and are being considered [Japanese Patent Application Laid-Open No. 62-219234
[Refer to Publication No. 62-219235, etc.]0 Problems to be solved by the invention With the above-mentioned configuration, it is possible to perform pre-treatment to sufficiently release gas from the polymer film, and to improve the degree of vacuum in the puff ground. Although there is a tendency for uniformity to be improved by methods such as sputtering, it has not yet been possible to obtain the physical properties uniformly over a large area as can be obtained by sputtering, so improvement has been desired. The present invention was developed in view of the above circumstances, and provides a manufacturing method that can improve both the performance and uniformity of a perpendicularly magnetized film.

Means for Solving the Problems In order to solve the above-mentioned problems, the method for manufacturing a perpendicular magnetic recording medium of the present invention involves forming a low-energy ion implantation layer on a polymer film, and then forming a perpendicular magnetization film by an ion plating method. It is designed to be completely formed.

Function: Due to the above-described structure, the method for manufacturing a perpendicular magnetic recording medium of the present invention has already caused the implanted ion layer to exist on the surface of the polymer film at a saturation level during ion plating, so that energetic ions can Improved crystal growth, as energy is spent on surface movement;
Defects are reduced, and the crystallinity and uniformity of the perpendicularly magnetized film are improved.

EXAMPLE Hereinafter, a method for manufacturing a perpendicular magnetic recording medium according to an embodiment of the present invention will be described in detail with reference to the drawings. The figure is an enlarged sectional view of a perpendicular magnetic recording medium obtained according to the present invention. In the figure, 1 is polyethylene terephthalate, polyphenylene sulfide, polyethersulfone,
It is a polymer film such as polyethylene naphthalate.

2 is a low energy ion implantation layer of 6 to 20 KeV,
It is preferable to implant ions of an element used for the perpendicularly magnetized film. The implantation is carried out under optimal conditions with a total ion implantation density in the range of 6 to 200 μm/d.

3 is Co-Or, Co-Ta, Go-Ti formed by an ion plating method such as a high frequency ion plating method or a DC accelerated ion plating method.
, Go-Ru, Go-V, Go-W,
0.05 of Go-Me, Co-0r-Wb, etc.
It is a perpendicular magnetization film of ~0.3 μm. 4 is a protective lubricant layer, which is made using plasma polymerization method or glow discharge decomposition method.

This is a layer of about 100 to 300 layers formed by a vacuum deposition method, a sputtering method, a two-reaction deposition method, a solution coating method, or the like.

In the following, a magnetic recording medium manufactured according to an embodiment of the present invention will be explained in more detail in comparison with a comparative example.

Using a polyethylene terephthalate film with a thickness of 1000 m (average surface roughness: 25 people, maximum roughness: 86 people),
After implanting KeV, 55μ people/colOcr ions, 13. '58 (MHz) during high frequency glow discharge
Ion plating was carried out by passing o -Or (Co: 79.8%) vapor flow, and 0.16μ
A Go-Or perpendicular magnetization film of m was formed. At this time, the film winding speed was 26 m/win. G.

-Or On the perpendicular magnetization film, 100% diamond-like hard carbon thin film was deposited by sputtering using graphite as a target, and 60% perfluorooctanoic acid was deposited by vacuum evaporation.
By manual deposition, an 8 mm wide magnetic tape was manufactured.

On the other hand, in the comparative example, the same polyethylene terephthalate film was used, and the surface was heated to 10 KHz and 0.1 Torr.
.

After performing glow discharge treatment under the conditions of 0□, Co-c
Ion plating was performed under the same conditions as r'6, a diamond-like hard carbon thin film and a perfluorooctanoic acid film were formed, and an 8 mm wide magnetic tape was prototyped.

All tapes of both, 8mm video modified with 0 gap length.
．． A rectangular wave with a bit length of 0.19 μm was recorded and reproduced using a 12 μm metal-in-gap type Sendust head, and the broadband C/N in a band of 12 (MHz) was compared.

10077 examples and comparative examples from any location! Thirty rolls of long tape were extracted and measured. One tape of the embodiment was temporarily determined as R, reference tape, and its C/N was set to O (dB). Reference
The C/N change along the tapeO length was uniform within 0.2 (dB). The 30th turn of the example was uniform from -o, a (dB) to +o, a (dB), but the comparative example was -2,6
(dB) to -0.6 (dB), the C/N was also low and the variation was large.

By the way, the C/N of the Go-Or perpendicular magnetization film formed by high-frequency sputtering is -0.4 to +0.3.
The winding speed of the film (in dB) was 2.2 (m 7 win ) with four targets arranged in series, which was below the remaining base of ion plating.

Effects of the Invention As described above, the present invention has an excellent effect in that a magnetic recording medium for high-speed, high-performance perpendicular magnetic recording can be manufactured.

[Brief explanation of the drawing]

The figure is an enlarged cross-sectional view of a perpendicular magnetic recording medium manufactured by a manufacturing method according to an embodiment of the present invention. 1... Polymer film, 2... Low energy ion implantation layer, 3... Perpendicular magnetization film. Name of agent: Patent attorney Toshio Nakao and 1 other person/-
--Kamolecular film 2 --- II also Ding 4 Me (-Iozo main) J # 3 --- Single layer j1 wind Iot Liao 屹

Claims (1)

[Claims] A method for manufacturing a perpendicular magnetic recording medium, comprising forming a low energy ion implantation layer on the surface of a polymer film, and then forming a perpendicular magnetization film thereon by an ion plating method.