JPS61199210A - Composite type magnetic head - Google Patents

Abstract

PURPOSE:To obtain a large reproduced output by constituting a pair of substrate cores, where metallic films having a high saturation magnetic flux density are provided on V-shaped magnetic gap forming surfaces, with a magnetic ferrite. CONSTITUTION:An Mn-Zn ferrite is worked to form substrate cores 10 and 11 having V-shaped magnetic gap forming surfaces, and Fe-Al-Si films 8 and 9 are formed on these surfaces by the sputtering method. Apexes of V-shaped parts are polished to attain 28mum width, and this pair of substrate cores are allowed to face each other with a magnetic gap 12 between them and are joined with a glass. A magnetic core 5 formed in this manner is inserted into a slider 4 consisting of a TiCaO3 and is buried and fixed by a glass 6, thus forming a composite magnetic head.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a magnetic head suitable for recording and reproducing information signals in combination with a high coercive force magnetic medium, and particularly relates to a magnetic head suitable for recording and reproducing information signals in combination with a high coercive force magnetic medium, and in particular, relates to a magnetic head suitable for recording and reproducing information signals in combination with a high coercivity magnetic medium. The present invention relates to a magnetic head in which a core chip having a metal magnetic film as a magnetic core is embedded in a ceramic slider with high mechanical reliability.

[Prior Art] FIG. 4 is a diagram showing the structure of a monolithic magnetic head that has been mainly used as a floating magnetic head in the past.

In FIG. 4, 1 is a part of the slider, and 2 is a magnetic core part, both of which are made of Mn--Zn ferrite.

Further, the magnetic gap 3 is made of glass. In a magnetic head with such a structure, the slider part 1 is made of Mn-Zn ferrite, which has poor mechanical reliability, so it is prone to chipping when it slides with the magnetic recording medium during startup or shutdown. However, there were drawbacks that led to head crash accidents. In order to improve this point, ceramic sliders in which a core chip is embedded in a ceramic slider have recently appeared, and the present inventors have also previously invented and proposed a composite head as shown in FIG.

In Figure 1, 4 is a part of the slider made of Ti, which has high mechanical reliability.
Ca O3, AI 203 T! A ceramic made of C, ZrO2, etc., 5 is a magnetic core made of Mn--Zn ferrite, and the core is embedded and fixed between the slider sliders 1 with glass 6. In addition, 7
represents the magnetic gap.

A magnetic head with such a configuration has excellent reliability during sliding since most of the surface that contacts the recording medium is made of ceramic with excellent mechanical strength.

However, since the core chip is made of Mn-Zn ferrite, its saturation magnetic flux density is at most 60
00G, which was insufficient for recording and reproducing in combination with a high coercive force magnetic recording medium.

On the other hand, it is known that by using a core in which a metal film with a high saturation magnetic flux density is formed on a substrate by sputtering, vapor deposition, or plating, sufficient writing can be performed on a medium with a high coercive force and the reproduction output can be increased. . Furthermore, in this case, as exemplified in Japanese Patent Application Laid-Open No. 51142716, it has been proposed to make the shape of the surface facing the magnetic gap V-shaped when forming a metal magnetic film on a non-magnetic substrate. .

However, when a metal film is formed on a nonmagnetic substrate, the film thickness is limited to about 100 μm at most, so the magnetic resistance of the entire core increases. For this reason, even if such a magnetic core is applied to a magnetic head having the configuration shown in FIG. 1 and combined with a high coercive force magnetic recording medium to perform high recording density recording and reproduction, satisfactory results cannot necessarily be obtained.

[Problems to be Solved by the Invention] As mentioned above, when a magnetic core having a structure in which the substrate material is a non-magnetic material is used, there is a problem that the magnetic resistance is large and sufficient recording and reproduction cannot be performed. , the present invention aims to solve this problem.

[Means for Solving the Problems] The structure of the present invention is to form a metal film with high saturation magnetic flux density on a ferrite substrate having a V-shape, and to form a metal film with a high saturation magnetic flux density on a ferrite substrate having a V-shape so that the apex of the ■-shape protrusion has a predetermined track width. After processing, the pair are butted together to form a magnetic core, and the magnetic core is embedded in a ceramic slider with excellent mechanical reliability, thereby obtaining a magnetic head with low magnetic resistance and high reproduction output. It is characterized by:

[Example] EXAMPLES The present invention will be explained in more detail below with reference to Examples.

A substrate core 10.11 having a V-shaped magnetic gap forming surface as shown in FIG. 2 was fabricated by processing Mn-Zn ferrite having a saturation magnetic flux density B of 4400 G. Next, Fe-AI- is deposited on this V-shaped magnetic gap forming surface.
A film 8.9 of 3i was formed by sputtering. in this case,
Transparent in high frequency! 1￥A 0.5 micron thick Fe-AI・-3i film and 0.1 micron thick S! so as not to lower the A! 02 films were alternately stacked. Fe-AI-
When the 3i film was analyzed, the composition of A was A I G, 0
, Si 9,9, Fe 84,1 wt%. Also, the magnetic properties are B+e-10400G, 1M
)-IZ magnetic permeability was 2200.

Next, after polishing the apex of the V-shaped portion to a width of 28 microns, the pair is placed on a magnetic gear 11 as shown in FIG.
They were made to face each other with the knob 12 interposed therebetween, and were bonded using glass. For bonding, glass was selected so that sufficient bonding could be achieved at a temperature of 760°C, and this temperature selection was based on the following reason. That is, Fe-AI-8i was formed by sputtering.
After forming a film, it is necessary to remove the stress applied to the film, but this is usually done at a temperature of 600°C or higher and
This is because it is necessary to perform annealing once at a temperature within a range in which the -AI-3i film is not oxidized.

Therefore, bonding at a temperature of 600° C. or higher has the advantage of also having the annealing effect and imparting sufficient soft magnetic properties. In addition, when glass is used to embed the magnetic core in the slider, it is not preferable to use glass because the joint portion of the core may become misaligned if the working temperature during embedding becomes high. For this reason, it is desirable that the working temperature of the bonded glass be at least 150°C higher than that of the buried glass.

The magnetic core 5 produced as described above is inserted into the slider 4 made of T1CaO3 as shown in FIG.
The composite magnetic head of the present invention was formed by embedding and fixing with glass 6 at a temperature of 80°C.

Using the magnetic head of the present invention having the above configuration, )-(C=800
FIG. 3 shows the results of measuring the write current characteristics of the reproduction output using a 0e magnetic recording medium. In Figure 3, Mn
-Znn Fushii [- is the substrate core and a magnetic core with a metal magnetic film formed is used A, non-magnetic ferrite Z
B using nFe20t as a substrate core and a magnetic core formed with a metal magnetic film, and M without using a metal magnetic film.
When the magnetic core was formed only with n -Zn ferrite], the result of C was shown. In this case, all the windings on the core are fixed at 28 turns, so the magnetic resistance is small I'v1n-
It is understood that when the substrate core is made of 7n ferrite (curve A), the reproduction output is larger than when the substrate is made of ZnFe20a (curve B), and the magnetic head of the present invention is superior.

Furthermore, it is clear that when the core is formed of only Mn-7-n ferrite (curve C), the reproduction output is much lower than that of the other two because the magnetic flux density is small.

As described above, the magnetic head according to the present invention can obtain a sufficient reproduction output for a recording medium with a high 1-1c, and is an extremely effective magnetic head in the field of magnetic recording.

In the above embodiment, the Fe-Δ1-81 film was described, but other metal films such as Fe-Ni and Fe-3i may also be used. For metal films, B1゜≧7
500G is sufficient. In addition, as a substrate, Mn
- Although the example of Zn ferrite is shown, BT1≧3500G
ferrite is sufficient to reduce the magnetic resistance of the core.

[Advantageous Effects of the Invention 1] As described above, the magnetic head of the present invention has a small magnetic resistance and a large reproduction output for a recording medium having a high coercive force, making it extremely useful as a magnetic head.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration external view showing an example of a magnetic head in which a core chip is embedded in a ceramic slider according to the present invention; FIG. 2 is a schematic configuration external view of a magnetic core having a V-shaped gap portion according to the present invention; FIG. 3 is a curve diagram showing measurement results of reproduction output and write current, and FIG. 4 is a schematic external view of a conventional monolithic magnetic head. 1... Ferrite slider, 2... Magnetic core part,
3.7.12...Magnetic gap, 4...Ceramic slider, 5...Magnetic core, 6...Glass, 8,
9...Metal magnetic film, 10.11...Board core graduation Figure 4 / Figure 3 Figure A Write current (mAρ-5) Procedure Ne city τE Incident display 1985 Special ii'F Name of the invention No. 40056 Composite magnetic head supplementary iT: Relationship to the Orirya case Patent applicant address 2-1-2 Marunouchi, Moyota-ku, Tokyo Name (5
08) Norio Kono, Representative of Hitachi Metals, Ltd.

Claims (1)

[Claims] 1. A pair of substrate cores having a metal film having a high saturation magnetic flux density on a V-shaped magnetic gap forming surface,
A composite magnetic head comprising: a magnetic core formed by joining the apexes of a letter shape so as to have a predetermined track width; and a non-magnetic and mechanically reliable magnetic core, the magnetic core being embedded in the slider. A composite magnetic head characterized in that the V-shaped substrate core is made of magnetic ferrite. 2. The composite magnetic head according to claim 1, wherein the V-shaped substrate core is made of ferrite with B_m≧3500G or more. 3. The composite magnetic head according to claim 1 or 2, wherein the metal magnetic film is made of a material with Bm≧7500G.