JPH0231309A - Manufacture of magnetic head - Google Patents

Abstract

PURPOSE:To strongly bond the magnetic gap of an MIG head, to prevent the generation of micro-crack and to manufacture the magnetic head with high yield by thin film-forming a glass on a ferro-magnetic metallic thin film and specifying the length of the magnetic gap with the glass. CONSTITUTION:'Sendust(R) is used as the ferro-magnetic metal of the magnetic head (MIG head) to have a metallic magnetic thin film. For a first core 2, a glass thin film 7 is formed on this 'Sendust(R) thin film with sputtering only by necessary thickness. Then, this first core 2 and a second core 4 to have a coil winding window 3 are bonded with using a fusion glass 5 and united with being formed so that the length of a magnetic gap 6 can be constant. Really, working is executed in a bar condition, in which the plural magnetic heads of this type can be obtained and they are finally cut off. Then, each magnetic head is obtained. Thus, the bonding intensity of a gap part goes to be large and the micro-crack can be prevented from being generated at the time of the manufacture. Then, the high performance magnetic head can be obtained with the high yield.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a magnetic head used in a magnetic recording/reproducing device.

[Conventional technology]

With the increase in the capacity of magnetic recording devices, recording media with high coercive force are being used, and in order to sufficiently record on these high coercive force media, it is necessary to increase the saturation magnetic flux density in the gap part of the magnetic head. A magnetic head with a highly magnetic thin film (
(hereinafter referred to as MIG head) has been developed and put into practical use.

The length of the magnetic gap of this MIG head is 1 μm or less, and since it is impossible to form a gap by pouring glass, a non-magnetic material of 5 ins. and Al t O
The MIG head is manufactured by sputtering n, defining the gap length, and integrating it by glass bonding.

[Problem to be solved by the invention]

However, in the above-mentioned conventional technology, the working temperature of glass bonding for forming the gap of the MIG head is 600°C.
Since it is before and after, 5ift and ferrite interface or 5i0
Mutual diffusion between the two surfaces is small, and when the inside of the gap after glass bonding is observed with an electron microscope after polishing the gap surface, a minute gap appears at the interface, as if 5i02 is missing.

In this way, because there is not enough bonding strength in the gap,
There is a problem in that microcracks occur in the ferrite in the portion facing the gap due to the processing load in post-processing. Therefore, the present invention is intended to solve these problems, and its purpose is to develop a high-performance mechanical engineering G.
The purpose is to firmly bond the magnetic gap of the head, prevent the occurrence of microcracks, and manufacture magnetic heads at a high yield.

[Means to solve the problem]

The method for manufacturing a magnetic head of the present invention includes forming a ferromagnetic metal thin film on the joining surface of a pair of magnetic core halves made of ferrite by vacuum thin film forming technology, and then abutting the pair of magnetic core halves to form a magnetic gap. The magnetic head is characterized in that a thin film of glass is formed on the ferromagnetic metal thin film, and the length of the magnetic gap is defined by the glass.

〔Example〕

FIG. 1 is a perspective view of an MIG head according to an embodiment of the present invention, which includes a first core 2 made of a ferromagnetic metal thin film 1 formed by vacuum thin film forming technology, and a second core 4 having a coil winding window 3. They are bonded using fusion glass 5 to form a magnetic gap 6 and are integrated. In reality, a bar is processed into which a plurality of magnetic heads can be obtained, and finally it is cut to obtain a magnetic head as shown in FIG.

At our company, Sendust is used as the ferromagnetic metal, and in order not to degrade the magnetic properties of the Sendust thin film, the glass bonding temperature is around 600°C. Therefore, when bonding the glass, it is required that the gap length is firmly defined and that the strength is sufficient. For this purpose, after sputtering the sendust film, SiO2, A1201. It is a glass whose main component is 20g of B, and its transition point is at the glass bonding temperature (60g).
A thin glass film 7 having a temperature of about 0° C. is formed on the sendust plate by sputtering to a required thickness. Alternatively, half of the required thickness is formed on the gap forming surface of the sendust film and the second core. Then, they are glass-bonded and integrated at a temperature of around 600°C. Further, it is desirable that the coefficient of thermal expansion of the glass thin film is set to be between that of ferrite and sendust films depending on the additive components. In addition, although the main component of the glass thin film is still in the future, it is desirable that it not contain a PB acid component as an additive element, prevent deterioration of the sendust film, and contain a trace amount of alkali metal component. Compared to the previous model, bonding through mutual diffusion has progressed, eliminating micro-gaps at the gear interface, and distortion due to residual stress during heating and cooling is also reduced, resulting in a magnetic head with high bonding strength and no micro-cracks in the ferrite during processing. It will be done.

〔Effect of the invention〕

As described above, according to the present invention, when two ferrite bodies are integrated while forming a magnetic gap, by forming a thin film of glass by sputtering on the magnetic gap surface, the gap portion is bonded. It has the effect of increasing strength, preventing the occurrence of microcracks during manufacturing, and obtaining a high-performance magnetic head with a high yield.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a magnetic head produced by the magnetic head manufacturing method of the present invention. 1... Ferromagnetic metal thin film 2... First core 3... Coil winding window 4... Second core 5... Fusion glass 6... Magnetic gap 7... Glass Thin film and above Applicant: Seiko Epson Corporation

Claims (1)

[Claims] In a magnetic head in which a ferromagnetic metal thin film is formed on the joint surface of a pair of magnetic core halves made of ferrite by vacuum thin film formation technology, and a magnetic gap is formed by abutting the magnetic core halves, a magnetic gap is formed on the ferromagnetic metal thin film. 1. A method of manufacturing a magnetic head, comprising forming a thin film of glass on the substrate, and defining the length of a magnetic gap by the glass film.