JPH01166331A - Method for manufacturing magnetic recording media - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method of manufacturing a magnetic recording medium for perpendicular magnetic recording, which is 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 the magnetic recording layer.
ANSACTIOH8ON MAGNET)O3)vo
d MA (r-21, No-3, 1217-1220
(1985)).

Perpendicular magnetic recording, in which demagnetization loss becomes more advantageous as the wavelength becomes shorter, requires a special film that can be magnetized perpendicular to the film surface, but efforts are still being made to put it into practical use. A magnetic recording medium for perpendicular magnetic recording has Go-Or, Co-Cr-Wb, Go-N on a soft magnetic layer such as Hl-Fe.
A so-called perpendicular magnetization film that can be magnetized in the perpendicular direction at i-0 or the like is used, or a perpendicular magnetization film is used on an underlying layer of Ti, Go, or the like.

Examples of methods for obtaining such a structure include high frequency sputtering, electron beam evaporation, and ion blating, but as is well known, high frequency sputtering provides good properties, but the film formation rate is slow; The electron beam evaporation method is unsuitable as a mass production technology; it requires a polymer film that can withstand high temperatures, and there are many practical problems to be overcome, and various proposals have been made [Japanese Patent Laid-Open No. 62-21923
No. 4, No. 62-219236].

Problems to be Solved by the Invention However, with the above-mentioned configuration, uniformity has not been improved by performing sufficient degassing treatment through pretreatment, glow discharge treatment, and improving the degree of vacuum in the pack ground. However, properties equivalent to those obtained by the sputtering method could not be obtained, and improvements were desired.

The present invention has been made in view of the above-mentioned circumstances, and provides a manufacturing method that can both improve the performance and ensure uniformity of a perpendicularly magnetized film.

Means for Solving the Problems In order to solve the above-mentioned problems, the method for producing a magnetic recording medium according to the present invention involves forming a soft magnetic layer on a polymer film along the same rotating support by chemical vapor deposition, immediately after forming the soft magnetic layer. The magnetic recording layer is formed by electron beam evaporation.

Effect The method for manufacturing a magnetic recording medium of the present invention has the above-described configuration, so that even if the soft magnetic layer formation speed is increased,
New gas will not be released and the characteristics will not deteriorate.
When a perpendicular magnetization film is formed by electron beam evaporation, the perpendicular magnetic recording medium is deposited directly on a clean surface, which improves its characteristics, making it possible to manufacture a high-speed, uniform, and high-performance perpendicular magnetic recording medium.

Embodiment Hereinafter, an embodiment of the present invention will be described with reference to the drawings. The figure is a configuration diagram of the main parts of the vapor deposition apparatus used to carry out the manufacturing method of the present invention. Take-out shaft, 4 is winding shaft, 6 is Co-0r, Co-Ti
, Go-Mo, Go-W, Go-0r-Nb
6 is an evaporation source container for MgO, ZrO2, etc., 7 is a pierced electron gun, 8 is an accelerated electron beam, 9 is a reaction tube made of a quartz tube, and 10 is a gas introduction hole. 11 is an external induction coil, 12 is an accelerating electrode, 13 is a vacuum container 14, and a vacuum exhaust system 15 is an anti-adhesion mask. In the apparatus shown in the figure, an induction heating type cylindrical can with a diameter of 50 cm is used as the rotating support, a 38 cs KMgO evaporation source is arranged below the can surface, and the reaction tube is configured to be heated with an electron beam of 6 V and a maximum of 60 KW. is 5.5 in the direction of film movement.
cm, and a rectangular quartz tube measuring 20 cm in the width direction.The aperture at the tip of the quartz tube is fixed at a position amm from the can surface, and the deposition center is at a creepage distance of 1 δ cm from the center of the aperture on the circumferential side of the can. It was placed in such a way that it would look like this.

In the equipment under these conditions, two permalloy thin films were formed on a polyethylene terephthalate film with a thickness of 15 μm and a Go-Or perpendicularly magnetized film was formed on the soil, and two well-known cylindrical cans were installed. The results of a comparative study in which an evaporation source is provided and a permalloy thin film and a Co-Or perpendicularly magnetized film are formed by electron beam evaporation will be described.

In the example, the can temperature was maintained at 5 o'CVC, and the film i
20! While moving Q/Dinte, press N1 (Go
)4゜Fa(Co4)i each 1.2[/win,
13.66 (MHz) 1.1 (
KW)'jz is applied to form a plasma, and the acceleration voltage is
00V is applied, 801Ni, permalloy thin film is 0.3
6 μm and continue to Go within an incident angle of 9.6 degrees.
-Or (Or: 20.6 wt%) at 3oKV
, accelerated at 3sKW, deposited 0.14μm Co-C
r A perpendicular magnetization film was formed.

On the other hand, in the comparative example, a polyamide-imide film with a thickness of 12 μm was used, and the pressure was 0.03 Torr 13.5 a (
M)lz) 0.8 (KW) glow discharge treatment
, 3 (see), then electron beam heating conditions 3
0KV, 40KW TeNi-Fa (Ni 80.3
wt%) film with a thickness of 0.35 μm was formed at an incident angle of 20 degrees or less (at a can temperature of 120'C), then at a can temperature of 180 degrees Celsius.
Co-0r (Cr: 2o, e
wt%) 2 aoxv, 41 (KW),
A Co-Or perpendicular magnetization film of 0.14 μm was formed. In both cases, "Fuomblin Z-25" manufactured by Montefluos was used as a perfluoropolyether lubricant.
A magnetic tape of 8 mm width was coated by hand, all 20 rolls were extracted, and C/N was compared using a modified 8 mm video. The head used is a metal-in-gap type amorphous head with a return path with a gap length of 0.16 μm, a bit length of 0.23 μm, and a C//N of band 1o (M-an).
One of the tapes in the example is taken as standard, and its C/N i
A relative comparison was made as O (dB) with other tapes.

In the example, the average value is Q, 3 (dB), and 20 rolls of tape are -
It was distributed in the range of 0.1 (dB) to 0.6 (+IB). On the other hand, the comparative example has an average value of -0.9 (dB) and 20
The tape of the volume is -1,9((IB) to -0,5((iB
) were distributed in the range. The present invention is characterized by the same performance as the conventional high-frequency sputtering method and can be obtained at high speed, and the permalloy thin film formation also includes a glow discharge treatment effect, making it possible to achieve a special glow. It can be fabricated without the need for a processing mechanism, and has the advantage of being more energy efficient than obtaining permalloy thin films using electron beam evaporation.

In this embodiment, the Co--Cr film was formed by electron beam evaporation, but the method is not limited to this, and it goes without saying that it may be combined with electric field evaporation or ion blating.

In addition, in the permalloy thin film, Mo(co)6 was used to form Ni-Fe-Mo, and ye( was used to form the Fe-Cr film).
co) 4°"C9"+2) 2 gases, and the same performance as the above-mentioned example was obtained in both cases.

Effects of the Invention As described above, the present invention has the excellent effect that a magnetic recording medium for uniform perpendicular magnetic recording can be obtained at high speed and at low temperatures.

[Brief explanation of the drawing]

The figure is a cross-sectional view of the main part of a vapor deposition apparatus used to carry out the manufacturing method of the present invention. DESCRIPTION OF SYMBOLS 1... Polymer film, 2... Rotating support, 6... Vapor deposition material, 9... Reaction tube.

Claims (1)

[Claims] A method for producing a magnetic recording medium, which comprises forming a magnetic recording layer on a polymer film along the same rotating support by electron beam evaporation immediately after forming a soft magnetic layer by chemical vapor deposition.