JPS59175036A - Production of magnetic recording medium - Google Patents

Abstract

PURPOSE:To enable formation of a magnetization film having excellent orientational property at a high speed in the stage of depositing by evaporation a vertical magnetization film on a substrate film moving along a rotary roll by making the width corresponding to the source for generating gaseous flow for vapor deposition larger than the width for the vapor deposition on the film plane in the moving direction thereof. CONSTITUTION:The vapor deposition of a vertical magnetization film of Co-Cr, etc. on a high polymer substrate or the non-magnetic underlying layer and soft magnetic underlying layer formed on said substrate while moving the substrate 1 in an arrow direction along a rotary support 2 is accomplished in such a way that the relation between the vapor deposition width Wd in the moving direction of the substrate film 1 and the width Wv corresponding to the vapor flow of the vapor deposition metal attains Wd:Wv=1:1.2-2. The aperture 14 of a stationary mask 5 along the support 2 is therefore provided in a way that the prescribed Wd is obtd. and the vapor flow 5 is generated by irradiating electron beams 8, 9 to a magnetic material 7 of an evaporating source. The vertical magnetization film having excellent orientational property is thus obtd. with good productivity.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a manufacturing method for mass producing perpendicular magnetic recording media with low loss in a short wavelength range.

Conventional Structures and Problems There is a perpendicular magnetic recording system as a magnetic recording medium with excellent short wavelength recording characteristics. It has been confirmed on a laboratory scale that this method has a feature not found in in-plane magnetized films, in that the demagnetizing field within the medium decreases as the wavelength becomes shorter. High expectations are placed on his ability to compete with the record he has used.

However, there are many problems that must be solved before such a system can be put into practical use.

One of these is media manufacturing technology.

Conventionally, perpendicular magnetic recording media have been used in research and development, and are made by forming a Co-Cr based alloy film on a polyimide substrate or aluminum disc using the high-frequency bipolar snow-link method. It was about a few inches in diameter.

However, it is difficult to assemble media manufacturing as an extension of this technology. This is because the film formation rate by sputtering is slow.On the other hand, the performance of the Co-Cr film made by the Snow + Tsuta link method as a perpendicularly magnetized film is excellent, and how can the film formation rate by vapor deposition be faster? The important issue for the time being is whether to obtain film performance equivalent to that obtained by high-frequency sputter linking without sacrificing its features.

OBJECTS OF THE INVENTION An object of the present invention is to provide a method for producing a medium with improved orientation, which is a measure of the performance of a perpendicularly magnetized film, by vacuum deposition.

Components of the Invention The manufacturing method of the present invention provides a method for producing a perpendicularly magnetized film on a substrate moving along a rotating support, in which a region of the rotating support is exposed to a vapor flow when a perpendicularly magnetized film is continuously obtained by vapor deposition on a substrate moving along the rotating support. The perpendicularly magnetized film with excellent orientation is obtained by performing evaporation in a state in which a width Wv of the vapor flow generation source corresponding to the substrate movement direction is larger than a width Wd of the vapor flow generation source in the substrate movement direction. do.

In the present invention, vapor deposition includes electron beam vapor deposition, induction heating vapor deposition, ion plate ink, electric field vapor deposition, and the like.

The rotating support is configured to be in close contact with the substrate and move at the same speed in order not to damage the back surface of the substrate (often referred to as the surface to be deposited) and to prevent thermal deterioration. It can be embodied as a cylindrical piece or an endless belt.

The substrate may be either a single polymer substrate or a polymer substrate with a nonmagnetic underlayer or a soft magnetic underlayer. Suitable polymeric substrates include polyhydride, polyhydride, polyethylene naphthalate, polyethylene terephthalate, and the like.

On a rotating support, the determination of the area where the substrate is exposed to the vapor flow is usually made with a stationary mask. The area where the substrate is exposed to the vapor flow is determined depending on the size of the opening in the direction of return of the fixed mask, but the size of the opening should be large from the viewpoint of productivity. However, as it is known that in order to obtain a perpendicularly magnetized film, it is better for the angle of incidence of vapor on the substrate to be close to 0°, so there are limitations of course.

Although there is no restriction on the direction of vapor flow perpendicular to the direction of movement of the substrate, it is natural that methods known in the art can be used to obtain a uniform film thickness in the width direction on a wide substrate. Within that range, the effectiveness of the present invention remains unchanged.

Wd is almost geometrically determined by the size of the opening in the fixed mask, and can be easily determined by temporarily fixing the substrate, performing vapor deposition, and measuring its width.

For example, Wv can be determined by moving an aluminum plate closer to the evaporation source and measuring the area to be evaporated to find out the approximate value, or if it is an electron beam evaporation source, it can be determined by This can be roughly determined from the range of two scans.

If Wv is too large relative to Wd, it will be disadvantageous in terms of vapor deposition efficiency, so a preferable value should be selected from 1.2 times Wd to at most 2 times Wd, as this is sufficient to obtain the effects of the present invention. .

DESCRIPTION OF EMBODIMENTS The manufacturing method of the present invention will be described below based on a specific embodiment.

The drawing shows an example of a winding vapor deposition apparatus used for carrying out the present invention. Before describing embodiments, the winding vapor deposition apparatus will be briefly described.

The substrate (1) is attached to a delivery shaft (
3) When moving from the winding shaft (4) to the winding shaft (4), the vapor is deposited by a vapor flow with a limited incidence angle through a fixed mask (5) having an aperture (a).

If the fixed mask (5) and the rotating support (2) are brought closer together, the width of the opening (2) in the direction of movement of the substrate and the width of the area where the substrate is exposed to steam on the rotating support will be reduced. It almost matches Wd.

An evaporation source is disposed directly below and opposite the rotating support (2). The evaporation source is configured as follows.

A magnetic material (7) constituting a perpendicularly magnetized film is charged in an evaporation source container (6), and the magnetic material (7) is Shock heats and vaporizes. The electron beams (8) and (9) are
It is scanned as needed in a focused state. Note that the width Wv of the evaporation region in the direction of movement of the substrate is approximately determined by the scanning region of each electron beam, and here Wd
(Configured in Wv.

These systems are configured inside the vacuum chamber αQ, and the vacuum chamber a
*The inside is exhausted by the exhaust system (b).

Example A cylindrical hollow palm with a diameter of 5 h was used as a rotating support (2), and an evaporation source container (6) was placed 28 times directly below the rotating support (2). For the electron beams (8) and (9), a method was used in which an electron beam gun focused to a diameter of 6 mm and a maximum of 2 mm was scanned by a magnetic field deflection. The substrate (1) is a polyethylene terephthalate (10.5 μm) with a side width of 50 mm, and is made of C079% Cr21 at a vacuum degree of IX 10-” Torr.
% was deposited with a thickness of 2 μm.

The winding speed was 42 m/1 m1n under the conditions of Wd, = 1.0 ctn, Wv = 14 c+++. X-ray diffraction of the Co7'Cr film revealed that the half-value width (Δθ50) of the rock intercarp of the (002) plane was 11 degrees. The half-width is a physical quantity that represents orientation dispersion, and the smaller the value, the better the orientation of the film.As a result of laboratory studies, if this value is 18 degrees or less, it can be used as a perpendicular magnetic recording medium. ,
This amount is known to exhibit good recording/reproducing characteristics.

Using the same vapor deposition apparatus as in Example [Experimental Example-1], Co - Ni -
Cr was deposited. Co 67%, Ni 18%, Cr
Using a component ratio of 20%, evaporation of 0.2 pm was performed at a vacuum degree of 1.
．． The test was carried out at 4×10 −6 Torr. The substrate used (
In 1), a permalloy vapor deposition film of 0.2 μm was pre-deposited on a boria trioxide (6 μm, 50 cIn width), and the winding speed was 55 m/rni n under the conditions of Wd = 13 cmv and Wv = 16 α. Ta. [Experiment example-1
] As a result of X-ray diffraction, Δθ5o was 9.8 degrees.

EXAMPLE A rectangular high frequency coil (1 turn) of 16 m x 60 c1n made of water-cooled copper pipe was placed directly below the rotor palm at a position 6c+++, and high frequency ionization was carried out at 4 x 10' Torr. Co 79%Cr 21
A perpendicularly magnetized film having a composition ratio of 0.2 μm was formed on a 50 m4 polyethylene terephthalate substrate (10.5 μm) using a composition ratio of 0.2 μm. Wd=15cm
Under the condition of Wv = 18 cIn, the input high frequency power is 98
At 0 watts, the reflected wave was 21 watts. (The Karasu wave number 5 was 18.56 RIh) and the winding speed was 62 m/min. The obtained Co--Cr film had a Δθ5o of 8 degrees.

Other experimental examples include Co-V, Co-Mo,
Co-W, Co-Ru.

Co-Ni-V, Co"Ni-Mo, Co-Ni
-W , Co -Ni -Ru i Even if it is rough, △θ5
It has been confirmed that a perpendicular magnetization film with o of about 10 degrees can be obtained by the method of the present invention at a winding speed of 80 m/min to 80 m/min.

In addition, when titanium or chromium is vapor-deposited on a polymer substrate and then a perpendicularly magnetized film is formed, or when a soft magnetic thin film such as Perm 0 is further formed on titanium or chromium and then a perpendicularly magnetized film is formed. It has also been confirmed that the above-mentioned performance can be sufficiently obtained even when obtained by the invention.

As a comparative example for each of the above experimental examples, commercially available 27
We discussed the conditions under which the same performance as that of the present invention can be obtained when using a 0° deflection type 16KW electron gun, and the case of a high-frequency suba/υ tarinter. , [Comparative Example] Co-Cr vertical having Δθ5o equivalent to [Experimental Example-1].

The conditions for obtaining a magnetized film by high-frequency sputtering are 1.
A polyethylene terephthalate substrate (10.5 μm) has a slow speed of 1.4 m/min, and even if an expensive substrate such as a polyethylene terephthalate substrate is used, the speed is 2.4 m/min.
I could only wind it with n. Furthermore, it was found that a Co--Cr film having the same Δθ5o could be obtained using a 270′ deflection type electron beam evaporation source. In addition, △σ,. is 17 degrees Co-
The winding speed when the Cr film was obtained was 12 m/min. By the way, Wd at this time = 2.5 cm,
Wv=1.2 am.

In addition, based on the winding vapor deposition apparatus shown in the clearly explained drawing, a discharge rope is provided near the substrate (1) and vapor deposition is carried out while the vicinity of the substrate is in a discharge state. Of course, it is also possible to perform high-frequency ionization by inserting it between the evaporation source container (6) and the evaporation source container (6).

According to the manufacturing method of the present invention as described in the detailed description of the invention, the width (Wd) in the substrate movement direction on the substrate exposed to the vapor flow described above is
) of the source of the vapor flow in the same direction (Wv
Since the perpendicularly magnetized film is deposited while satisfying the condition that the perpendicularly magnetized film is larger than that of the conventional method, a medium with good orientation can be obtained with productivity more than 10 times higher than that of the conventional method.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram of a winding vapor deposition apparatus according to a specific embodiment of the manufacturing method of the present invention.゛ □(1)...Substrate,
(2)...Rotating support body, C5)...Fixed mask, (
6)... Evaporation source container, (7)... Magnetic material, (8)
(9)...Electron beam, C41...Opening part, Wd.
...Width in the direction of substrate movement of the area where the substrate is exposed to the vapor flow, Wv... Width corresponding to the direction of substrate movement at the source of the vapor bed Agent Yoshihiro Morimoto

Claims (1)

[Claims] (2) Width in the substrate movement direction of a region on the rotating support where the substrate is exposed to the vapor flow when a perpendicularly magnetized film is continuously obtained by vapor deposition on the substrate moving along the rotating support network. A method for manufacturing a magnetic recording medium in which the width of the vapor flow source corresponding to the substrate movement direction is larger than that of the vapor flow.