JPH041920A - Magnetic recording medium and its production - Google Patents

Abstract

PURPOSE:To prevent damages on a magnetic layer and to improve durability of the disk by successively forming a magnetic layer and a protective film on a nonmagnetic supporting body and using a boron nitride protective film as the protective film. CONSTITUTION:A magnetic layer 102 and a protective film 103 are successively formed on a nonmagnetic supporting body 101, and a boron nitride protective film is used as the protective film 103. The material of the protective film evaporates instantaneously at high temp. of plasma generating up above the supporting body and forms the protective film 103 of boron nitride thin film on the supporting body. This protective film 103 is uniform without variation in the composition. Since space for generating the plasma flame is up above the supporting body 101 and is parallel to the supporting body 101, the thin film thus formed is dense. Thereby, durability of the medium is improved without damaging the magnetic layer 102.

Description

[Detailed Description of the Invention] [Summary] To improve durability by eliminating damage to the magnetic layer in a magnetic recording medium in which a magnetic layer and a protective film are sequentially formed on a non-magnetic support and a method for manufacturing the same. The purpose of the present invention is to provide a magnetic recording medium in which a magnetic layer and a protective film are sequentially formed on a non-magnetic support, in which a boron nitride protective film is used as the protective film. The configuration was as follows. Further, a non-magnetic support having a magnetic layer formed on its surface is placed below the vacuum container, and a plasma flame is generated above the support in the vacuum container, and in this state, the The structure is such that a boron nitride film is formed on the surface of the support by evaporating the boron powder and nitrogen that are the protective film material supplied from above.

[Industrial application field]

The present invention relates to a magnetic recording medium in which a magnetic layer and a protective film are sequentially formed on a nonmagnetic support, and a method for manufacturing the same.

In recent years, magnetic disk drives have been moving toward lower flying heights of heads as recording density has increased.

For this reason, the risk of crashing increases, and it is necessary to improve the durability of the protective film.

[Conventional technology]

2. Description of the Related Art Conventionally, in magnetic disks (magnetic recording media) used in magnetic disk devices, sputtering methods and vapor deposition methods have been adopted to form thin films on substrates.

[Problem to be solved by the invention]

However, in the conventional methods of forming thin films using sputtering and vapor deposition, the saturated vapor pressure differs significantly at each temperature, resulting in poor reproducibility of film formation conditions such as evaporation rate, and dense thin films with uniform composition are not possible. I can't get it. Furthermore, carbon and other materials are used as protective film materials, but graphite films have low durability and require a thick protective film, while diamond films have high durability and can be made thin. However, conventional sputtering and vapor deposition methods cannot be used because they cannot produce very accurate diamond structures and it is difficult to understand the conditions.

An object of the present invention is to provide a magnetic recording medium that can eliminate damage to the magnetic layer and improve durability, and a method for manufacturing the same.

[Means for Solving the Problem] In order to achieve the above-mentioned object, the present invention provides a magnetic recording medium in which a magnetic layer and a protective film are sequentially formed on a non-magnetic material, in which a boron nitride protective film is used as the protective film. The structure uses a membrane. Further, a non-magnetic protective film having a magnetic layer formed on its surface is disposed below the vacuum vessel, and a plasma flame is generated above the support in the vacuum vessel, and in this state, a plasma flame is generated above the support in the vacuum vessel. The structure is such that a boron nitride film is formed on the surface of the support by evaporating the boron powder and nitrogen that are the protective film material supplied from the support.

[For production]

The overcoat material is exposed to 10,000 yen of the plasma above the support.
It evaporates instantaneously due to the high temperature exceeding .degree. C., thereby forming a protective film of boron nitride thin film on the support. The protective film formed in this manner has no fluctuation in composition and is uniform. Furthermore, since the plasma flame generation space is located above the support and parallel to the support, the formed thin film becomes dense.

〔Example〕

The invention will now be described in detail in conjunction with the drawings.

FIG. 1 is a cross-sectional view showing the structure of a magnetic disk (magnetic recording medium) 100. The magnetic disk 100 has a ferromagnetic metal thin film (magnetic layer) 102 on the surface of a disc-shaped nonmagnetic support 101 made of aluminum or the like. and a boron nitride protective film 103 are sequentially formed. Note that, in practice, the magnetic disk 100 is used with a friction-reducing lubricant layer 104 formed on its surface.

FIG. 2 shows an outline of the structure of the apparatus used to form the boron nitride protective film 103 of the magnetic disk 100. In FIG. 2, 1 is a vacuum container, 2 is a protective film material provided on the top of the vacuum container 1, a supply part for plasma flame forming material, 3 is a high frequency coil, and 4 is provided below in the vacuum container 1. The holding table 5 is an exhaust part. The holding table 4 is driven and rotated by a drive source (not shown) provided outside the vacuum container 1. The exhaust section 5 is for maintaining the inside of the vacuum container 1 at a predetermined pressure, and is connected to an external exhaust pump (not shown) via a valve or the like.

Formation of the boron nitride protective film is performed using this apparatus according to the following procedure.

When forming a protective film, the non-magnetic support 101 with a magnetic layer formed on its surface is set on the holding table 4, and the high-frequency coil 3 is energized to supply plasma gas (A) from the supply port 6 of the supply unit 2.
r) and sheath gas (02). The supplied gas is blown out from around the lower part of the supply section 2 into the vacuum container 1 as shown by the dotted arrow line, and is excited by the magnetic field of the high frequency coil 3 to become a plasma flame. This plasma flame is
It is formed above the support 101 in a space parallel to the support 101. In this state, the support body 101 is rotated, and the protective film material is supplied from the supply lower part above the supply section 2. As the protective film material, a material in which boron powder is dispersed in a carrier gas (N) or a material in which boron nitride powder is dispersed in a carrier gas is used. The supplied protective film material is blown out from the center of the lower part of the supply section 2 into the vacuum container 1 as shown by the solid arrow line, and the 10,000 yen of the plasma flame is blown out.
It evaporates instantaneously due to the high temperature exceeding .degree. C. and is deposited on the surface of the support 101 (on the ferromagnetic metal thin film). In addition,
The peripheral wall of the vacuum vessel 1, whose temperature rises due to the generation of plasma flame, is cooled by the cooling water flowing in from the cooling water outlet 8 and flowing out from the cooling water outlet 9.

As described above, the boron nitride protective film of the present invention is formed by instantaneously evaporating and depositing the protective film material using a plasma flame, so that the boron nitride protective film has no fluctuation in composition and is uniform. Furthermore, since the plasma flame generation space is located on the support body 101 and is parallel to the support body 101, the formed thin film becomes dense.

〔Effect of the invention〕

As described above, according to the present invention, it is possible to obtain a uniform and dense boron nitride film, thereby eliminating damage and damage to the magnetic layer and improving the durability of the disk. This greatly contributes to levitation.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing the structure of the magnetic recording medium of the present invention, and FIG. 2 is a schematic explanatory diagram of the structure of an apparatus used for forming a boron nitride protective film in an embodiment of the present invention. A vacuum container, 100 a magnetic disk (magnetic recording medium), 101 a nonmagnetic support, 102 a ferromagnetic metal thin film (magnetic layer), and 103 a boron nitride protective film.

Claims (1)

[Claims] 1. In a magnetic recording medium in which a magnetic layer and a protective film are sequentially formed on a non-magnetic support (101), a boron nitride protective film (103) is used as the protective film. Features of magnetic recording media. 2. Non-magnetic support (101) with a magnetic layer formed on the surface
is placed below the vacuum container (1), a plasma flame is generated above the support (101) in the vacuum container (1), and in this state, protection is supplied from above the vacuum container. A method for manufacturing a magnetic recording medium, characterized in that a boron nitride protective film (103) is formed on the surface of the support (101) by evaporating boron powder and nitrogen, which are film materials, by the plasma flame.