JPH01102706A - Composite magnetic head - Google Patents

Abstract

PURPOSE:To attach a superior magnetic characteristic, to suppress the generation of a crack at minimum, and to improve reliability by forming a thin film of 'Sendust(R)' only on a plane forming the front gap part and the back gap part of the I core of a magnetic head chip, and inserting an I core side to the groove of a slider facing to the discharging end side of a medium. CONSTITUTION:In the magnetic head chip 2, the thin film of 'Sendust(R)' with width 1-10mum is formed on the plane forming the front gap part 2d and the back gap part 2f of the I core 2B, and also, on either plane both planes or the plane or on one side of a C core confronting with a thin film plane and the above plane, a thin film 6 of an SiO2 and a thin film of glass are formed sequentially, then, the C core 2A is jointed with the I core 2B. Furthermore, a step part whose gap depth is larger than that of the front gap part 2d is formed at the confronting part of a magnetic recording medium, and furthermore, and reinforcing glass 4b is arranged on the side plane of at least on one side of the back gap parts. The magnetic head chip is inserted to the groove of the slider by facing its I core side to the discharging end side of the magnetic recording medium. In such a way, it is possible to attach the superior magnetic characteristic and also, to obtain low incidence of film peeling and cracking and to improve the reliability.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a composite magnetic head used in computer hard disks and the like.

[Conventional technology]

In recent years, a composite magnetic head as shown in Fig. 5 has been developed as a magnetic head that flies approximately parallel to a rotating magnetic recording medium (hereinafter referred to as the medium).
It is disclosed in Japanese Patent No. 7-189173.

That is, the above-mentioned composite magnetic head has a slider 1 which is made of a non-magnetic material and is provided on the medium outflow side of one of the two slide rails 1a as shown in FIG.
A magnetic head chip (hereinafter referred to as a chip) 2 is formed by bonding and reinforcing a C core 2a and a core 2b made of a magnetic material and having a winding groove 2c with a bonded glass and a reinforcing glass 4b. It is then assembled as shown in FIG. 5(C) by inserting it and adhering it with adhesive glass 4c.

Conventionally, chips of composite magnetic heads have been mainly made of ferrite. on the other hand,
With the recent increase in the density of magnetic recording, it is necessary to increase the coercive force of the medium, and high coercive force media have appeared.

However, since the ferrite has a relatively low saturation magnetic flux density, there is a problem in that it is not possible to write to a high coercive force medium sufficiently.

For this reason, conventionally, as shown in FIG. 6, a magnetic thin film 5 of Fe'Si or an amorphous alloy is coated on both sides of the winding groove 1c side of the C core la and the opposite side of the core 2b. A structure formed by a sputtering method or the like and bonded with glass 4 has been developed, and is disclosed in, for example, Japanese Patent Laid-Open No. 184712/1983.

[Problem that the invention seeks to solve]

However, in the case where a magnetic thin film is formed on the entire opposing surfaces of the C core and the ■core, the magnetic thin film is formed on both sides of the gap part, so the magnetic field distribution of leakage magnetic flux formed from the front gap part to the medium side is steep. If the magnetic field becomes too large, the perpendicular component of the magnetic field becomes large and the in-plane recording component becomes small, resulting in insufficient magnetic properties.

In addition, magnetic thin films are formed on both sides of the opposing surfaces.
It is thought that the residual stress in the core due to the thin film increases. Furthermore, cracks are likely to occur in the reinforced glass during slicing or during the process of fixing the chip to a non-magnetic slider, resulting in a problem of low manufacturing yield and poor product reliability.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems and to provide a composite magnetic head that has excellent magnetic properties and is less prone to cracking and is highly reliable.

Means for Solving Problem C] The present invention has been made to achieve the above object, and
A magnetic head chip in which a C core made of a magnetic material and having a winding groove and an opposing core are joined by glass at the front gap part and the back gap part, and the inside of the winding groove is reinforced with glass.
In a composite magnetic head that is inserted into a groove on the outflow end side of the magnetic recording medium provided in the slide rail of a slider made of a non-magnetic material and bonded with glass, the magnetic helad chip is inserted into the front gap and back gap of the core. Apply a thin film of Sendust 1 to 10μ only on the surface where the part will be formed.
SiO□ is formed to a thickness of
A thin film and a glass thin film are sequentially formed to form the C core and
When bonding to the core, glass is flowed in so that reinforcing glass is placed on at least one side of the rear gap when the magnetic head chip is completed, and a step portion deeper than the gap depth of the front gap is formed on the side facing the medium. It is characterized in that the magnetic herad tip is inserted into the groove of the slider with the I-core side facing the outflow end of the medium.

[For production]

A magnetic thin film made of sendust is formed only on the gear part forming surface of the core, and this I core is placed on the outflow end side of the medium, so the magnetic field distribution of leakage magnetic flux in the gap becomes steep at the outflow end side of the medium. This allows recording to occur with a sharp transition in magnetization in the recorded medium.

Furthermore, a magnetic thin film is formed only on the gear part forming surface,
Neither the C core nor the (2) core is formed within the winding groove, and due to the effect of the reinforcing glass placed on the side surface of the core, cranks are less likely to occur in the reinforcing glass, and reliability can be improved.

(2) The thin film of sendust was formed on the gear forming surface of the core because sendust has a large saturation magnetic flux density B, is crystalline, and has excellent heat resistance.

Further, the reason why the film thickness is set to 1 to 10 μm is that if it is less than 1 μm, the output will be too low, but if it exceeds 10 μm, the film will easily peel off or crack.

Furthermore, since a step portion deeper than the gap depth of the front gap portion is formed on the side of the chip facing the magnetic recording medium, it is easy to regulate the trunk width T8.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 and 2.

FIG. 2 (Al is a front view showing a state in which the C core and I core are joined.

FIG. 2 (tel is a perspective view thereof).

First, as shown in FIG. 2, a C core block 2A made of Mn-Zn ferrite and having a winding groove 2c and an I core block 2B without a winding groove are prepared, and a gear part of each front gap part 2d is formed. Surfaces 2e, 2e' and gear lug forming surfaces 2g, 2g' of pack gap portion 2f
2. Gap forming surface 2e' of core block 2B.

A thin film 5 of Sendust is applied to only 2g' by sputtering.
It was formed in the range of ~10 μm. The C core and I core have grooves formed therein for the reinforcing glass to flow in, as shown in FIG. 2(b).

Next, a thin film of 5in2B203 PbO-based bonding glass 4a having a softening point of 630° C. was formed to a thickness of 0.1 μm on the surface of the thin film 5 of Sendust and the gear portion forming surface 26.2g of the C core by sputtering. .

Next, the C core block 2A and the core block 2B are butted together, heated to 750°C in N2 gas and held for 30 minutes to bond them together.
Reinforcement was performed by filling the winding groove IC and the reinforcing groove with iOz-8203-PbO-based reinforcing glass 4b.

After cutting this bonded and reinforced block to a thickness of approximately 0.6 mm, a front gap 2 is created on the side facing the medium 2h.
Step portion 2s with a depth d deeper than the gap depth Gd of d
was formed parallel to the medium facing surface 2h, and the entire surface was lapped to form the chip 2 shown in FIG.

The finished external dimensions of this chip 2 are: ■ Core width 0.3
Overall width including 4 mm 1.1 +n, height 7.3
mm, thickness 0.6 mm.

Next, this chip 2 was inserted into the groove 3 on one medium outlet end side of the slide rail 1a of the ceramic slider 1 made of calcium cutic acid, and SiO□-820° with a softening point of 445°C and a melting temperature of 540°C was inserted. After bonding with -pbo adhesive glass, final finishing was performed to obtain a composite magnetic head similar to that shown in FIG. 5(C).

The composite magnetic head of the present invention manufactured as described above (
Δ), one in which Sendust thin film 5 is formed on both sides of the gear lug forming surface 2e and 'le' of the front gap part 2d (B), and one in which it is formed on the surface 2e on the C core 2a side (C).
FIG. 3 shows the results of testing the characteristics of the samples (D) in which the Sendust thin film 5 was not formed on either surface using a magnetic head tester.

As is clear from FIG. 3, the device (A) of the present invention has a higher resolution than the others (B), (C), and (D).
It also has excellent output.

Next, FIG. 4 shows the results of tests of the present invention with different thicknesses of the sendust thin film.

As seen in Figure 4, in order to obtain the desired output,
Although a film thickness of 10 μm or more is required, peeling or cranking of more than 10 μm may occur, making the product unusable.

Next, we looked at the rate of occurrence of peeling and cracking during slicing (%).
), a thin film of sendust 5 like that of the present invention
is formed only on surface 2 e / of I core 2b, and C
As a result of comparing the core 2a and the one formed on both sides 2e and 2e' of the core 2b, as shown in the table below, it was confirmed that the occurrence rate of k of the present invention is extremely low and the reliability as a product is high. Ta.

In the above embodiment, the chip 2 with the step portion 2S formed on the left side as shown in FIG. 1(b) is inserted into the groove 3 on the left side of the slider 1 as shown in FIG. 5(a). Although the description has been given of the case for the upside, in which the tip is bonded to the right side, the same effect can be obtained for the downside, in which a chip with a step portion formed on the right side is inserted into the groove on the right side and bonded.

〔Effect of the invention〕

As described above, the composite magnetic head of the present invention has excellent magnetic properties and is highly reliable with a low incidence of deprinting and cracking.

[Brief explanation of the drawing]

Figure 1 (al is a front view of the chip showing one embodiment of the present invention, Figure 1 (b) is a side view of the same, Figure 2 (al is a front view of the chip showing the state before bonding, (b) is also a perspective view,
Figures 3 and 4 are diagrams showing the results of tests on magnetic thin films, Figures 5 (a), (b), (C1 is a diagram showing an example of a conventional composite magnetic head, and (a) is a slider of,(
b) is a perspective view showing the chip, (C1 is a perspective view showing the assembled state, and FIG. 6 is a perspective view exaggerating the main parts of the conventional one. 1 Nislider, 2: Chip, 3: Groove, 4 Niglass) , 4
a: Bonded glass, 4b: Reinforced glass, 4c: Adhesive glass, 5: Sendust thin film, 6: SiO□ thin film, 7: Reinforcement groove, 1a varnished rail, 2a: C core, 2b: I core, 2C: Winding wire Groove, 2d; Front gap portion, 2e, 2
e': Gear lug forming surface, 2f: Back gap part,
2g. 2g': Gap forming surface, 2h: Medium facing surface, 2S two-step portion, Gd: gap, 7 depth, d depth of two-step portion.

Claims (1)

[Claims] A core made of a magnetic material and having a winding groove (C core) and an opposing core (I core) are joined by glass at the front gap part and the back gap part,
A composite magnetic head in which a magnetic head chip reinforced with glass in the winding groove is inserted into a groove on the outflow end side of the magnetic recording medium provided in a slide rail of a slider made of a non-magnetic material, and bonded with glass. In the magnetic head chip, a thin film of Sendust is formed to a thickness of 1 to 10 μm on the surface forming the front gap portion and the back gap portion of the I core, and the thin film surface and the surface of the C core opposite to this surface are formed with a thin film of Sendust to a thickness of 1 to 10 μm. A SiO_2 thin film and a glass thin film are sequentially formed on both surfaces or either one of the surfaces,
The C core and I core were joined together, and a step portion deeper than the gap depth of the front gap portion was formed on the side facing the magnetic recording medium, and furthermore, reinforcing glass was arranged on the side surface of at least one of the rear gap portions. 1. A composite magnetic head, characterized in that the magnetic head chip is inserted into the groove of the slider with the I-core side facing the outflow end side of the magnetic recording medium.