JPH0447520A - Magnetic recording medium - Google Patents

Abstract

PURPOSE:To improve the high-density recording in horizontal recording by providing a thin film of a ferromagnetic cobalt alloy having the parallel axis of easy magnetization parallel on the crystal face of a nonmagnetic metallic layer having the prescribed crystal face parallel with an information recording surface. CONSTITUTION:After a nickel phosphorus layer 2 is deposited on an aluminum substrate 1, a lower layer 3 consisting of a chromium alloy, a magnetic layer 4 consisting of the cobalt alloy, a protective film 5, and a lubricating film 6 are successively formed by a sputtering technique thereon. Second elements (V, Mo, Ti, Ta, etc.) are added to the chromium layer at this time. The (100) face of the chromium is then oriented by the precipitation of the 2nd element and the lower layer 3 of the chromium alloy is formed. The (200) face of the atoms of the lower layer 3 of the chromium is paralleled with the recording surface of the substrate 1 in such a manner, by which the cobalt alloy atoms are stuck to the chromium structure along the (110) face. The axis of easy magnetization of the cobalt alloy is paralleled with the disk surface and the magnetic characteristics optimum for high-density recording are applied to the magnetic recording layer.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a magnetic recording medium, and particularly to a magnetic recording medium suitable for use in an external storage device of a computer.

[Prior Art] A conventional magnetic recording medium consists of a non-ferromagnetic substrate, a non-ferromagnetic metal layer provided on this substrate, a magnetic recording layer formed on the metal layer, and this magnetic recording layer. It has a protective layer and a lubricating layer for protecting the .

[Problem to be solved by the invention]

In this conventional magnetic recording medium, in order to use a cobalt alloy magnetic medium, which inherently has strong perpendicular anisotropy, for recording in the longitudinal direction, a nonmagnetic layer must be provided under the magnetic layer.

However, it has conventionally been extremely difficult to strictly set this magnetic anisotropy with the intention of improving magnetic properties.

[Object of the Invention] The object of the present invention is to improve the disadvantages of the conventional example, to enable the use of cobalt alloy magnetic media with particularly strong perpendicular anisotropy for recording in the longitudinal direction, and thereby to improve the high performance in horizontal recording. An object of the present invention is to provide a magnetic recording medium with improved density recording.

[Means to solve the problem]

In the present invention, a substrate made of a non-ferromagnetic material, a non-ferromagnetic metal layer mounted on the substrate and having a predetermined crystal plane parallel to the information recording surface, and The structure includes a ferromagnetic cobalt alloy thin film having parallel easy axes of magnetization. This aims to achieve the above-mentioned purpose.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIG.

In FIG. 1, reference numeral 1 indicates a substrate made of aluminum as a non-ferromagnetic member.

This substrate 1 has circumferential grooves (not shown) on its surface.
is formed. This groove has the effect of improving magnetic properties because the particles are well arranged along the groove.

After a nickel-phosphorous layer 2 is applied on this substrate 1,
Chron alloy lower layer 3. A coating layer is formed by epitaxially growing a cobalt alloy magnetic layer 4, a protective film 5, and a lubricating film 6 in sequence by sputtering.

Here, when forming the chromium lower layer, the temperature is raised to 150°C or higher, and sputtering is performed at 1000 to 4000 sputtering/sec to make the thickness 50 to 200 sputtering (100).
A chromium layer is formed with the surface facing the lower layer. At this time, a second element (V, Mo, Ti, Ta) is added to the chromium layer.
etc.), the (100) plane of chromium is oriented by precipitation of the second element. As a result, a chromium alloy lower layer 3 is formed.

In other words, in order to optimize the magnetism of thin-film cobalt alloy media in terms of horizontal recording, the cobalt atoms in the hexagonal close-packed structure are
The axis must be oriented parallel to the recording surface. For this purpose, the cobalt atoms must be converted to cobal) (110) or (100
) must adhere to the underlying surface aligned along the plane. Therefore, as mentioned above, by making the (200) plane of the atoms in the lower chromium layer parallel to the recording surface of the substrate 1, the (110)
Cobalt alloy atoms can be attached to the chromium structure along the surface.

〔Effect of the invention〕

As described above, according to the present invention, by adding a second element to the chromium underlayer, the easy axis of the cobalt alloy becomes parallel to the disk surface, giving the magnetic recording layer optimal magnetic properties for high-density recording. It is possible to provide an unprecedented and excellent magnetic recording medium that can perform the following functions.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing a part of a magnetic recording medium according to an embodiment of the present invention. DESCRIPTION OF SYMBOLS 1... Aluminum substrate, 2... Nickel-phosphorous layer, 3... Chromium alloy lower layer, 4... Cobalt alloy magnetic layer, 5... Protective film, 6... Lubricating film. Applicant Nippon Electric Co., Ltd. Agent Patent Attorney Yudai Takahashi

Claims (1)

[Claims] (1) A substrate made of a non-ferromagnetic material, a non-ferromagnetic metal layer mounted on the substrate and having a predetermined crystal plane parallel to the information recording surface, and a non-ferromagnetic metal layer on the crystal plane of the non-ferromagnetic metal layer. A magnetic recording medium comprising: a ferromagnetic cobalt alloy thin film having parallel easy axes of magnetization.