JPS63311610A - Composite magnetic head - Google Patents

Abstract

PURPOSE:To record the transition width of magnetization rapidly by forming a magnetic thin film made of a 'Sendust(R)' only to a gap forming face of an I core and placing the I core to the flowout end of a medium. CONSTITUTION:The thin film 5 made of a 'Sendust(R)' is formed in the thickness of 1-10mum only to a face formed with a front gap 2d and a back gap 2f of the I core 2b, a SiO2 thin film 6 and glass thin film 4a are formed sequentially to the face of the thin film 5 and both or either face of the C core 2a opposed to the face of the thin film 5 to bond the C core 2a and the I core 2b and a step 2s deeper than the depth of gap of the front gap 2d is formed to the face opposed to the medium. Then the magnetic head chip is inserted to a slot 3 of a slider 1 while the I core 2b is directed to the flowout end of the medium. Thus, excellent magnetic characteristic is obtained, occurrence of cracks is less and the composite magnetic head with high reliability is obtained.

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 composite magnetic head has Pt55 (a)
In the slider 1 made of a non-magnetic material shown in FIG. A magnetic head chip (hereinafter referred to as a chip) 2 formed by bonding and reinforcing the core 2b with a bonding glass and a reinforcing glass 4b is inserted, and the core 2b is bonded with an adhesive glass 4c and assembled as shown in Fig. Pt55 CC>. It is something that

Conventionally, chips of upstream composite magnetic heads are 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, magnetic thin II5 such as Fe-8i or an amorphous alloy has been applied to the winding #l groove 1c side of the C core 1a and the entire surface of both sides of the I core 2bl opposite thereto. 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 I core, the magnetic thin film is formed on both sides of the gap portion, so the magnetic field distribution of leakage magnetic flux formed from the front gap portion to the medium side is steep. If the magnetic field becomes too large, the perpendicular component of the recording 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 reinforcing lath during slicing, resulting in a low manufacturing yield and poor reliability as a product.

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, fewer cracks, and is highly reliable.

[Means for solving problems]

The present invention has been made to achieve the above objects,
A magnetic head chip in which a C core made of a magnetic material and having a winding groove and an opposing I core are joined by glass at a front gap portion and a back gap portion, and reinforcement is provided by glass within the winding groove. of,
In a composite magnetic head that is inserted into a groove with a diameter of mm in which a magnetic recording medium flows out provided in a slide rail of a slider made of a non-magnetic material and is bonded with glass, the magnetic head chip is attached to a front gap portion and a back gap portion of an I core. 1 to 10 thin films of Sengest are applied only to the surface forming
S is formed to have a thickness of μ theory, and on both or one of the thin film surface and the surface of the C core opposite to this surface.
i By sequentially forming an O2 thin film and a glass thin film,
The core and the eco-7 are joined together, and a step portion deeper than the gap depth of the front gap portion is formed on the medium facing surface side, and the magnetic head chip is placed with the I core side facing the outflow end side of the medium. It is characterized in that it is inserted into the groove of the slider.

[For production]

A magnetic thin film made of sendust is formed only on the gear part formation surface of one core, and this I core is placed on the media outflow end side, so the magnetic field distribution of leakage magnetic flux in the ear part becomes steep on the media outflow end side. 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,
Since neither the C core nor the (2) core is formed in the winding A, cracks are less likely to occur in the reinforced glass, and reliability can be improved.

The reason why a thin film of sendust was formed on the gear forming surface of the core is that sendust has a large saturation magnetic flux density B, is crystalline, and has 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 insufficient, 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 Tw in the track.

〔Example〕

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

MS1 figure (a) is a front view showing the state before joining the C core and 1 core.

First, as shown in FIG. 2, two C core blocks made of Mn-Zn7 elite and having a winding groove 2c and an I core block 2B without a winding #l groove are prepared, and the gears in the front gap portion 2d of each are prepared. Part forming surfaces 2e, 2e' and gear lug forming surfaces 2g, 2g of the back gap part 2f
(1) A thin film 5 of sendust was formed in a range of 1 to 10 μm by sputtering only on the gear portion formation surfaces 2 e ′ and 2 g ′ of the core block 2B.

Next, the thin lI5 surface of the sendust and the C core gear'
/ S i O2-B zo on the drop portion forming surfaces 2e and 2g,
A thin film of bonding lath 4a made of + p bo system and having a softening point of 630° C. was formed to a thickness of 0.1 μm by sputtering.

Next, the above-mentioned C core block 2A and Ecore block 2B are butted together, heated to 750°C in N2f gas and held for 30 minutes to bond them, and Si with a softening point of 600°C
Reinforcement was carried out in the winding #i groove 1c with O□-BxOs-Pb0 system reinforcing glass 4b.

After cutting this joined and reinforced block to a thickness of approximately 0°6, a 70-ton gap 2d is placed on the side facing the medium 2h.
A step portion 2s with a depth d deeper than the gap depth Gd was formed parallel to the medium facing surface 2h, and the entire chip was subjected to two-tube processing to complete the chip 2 shown in FIG. MS1.

The finished external dimensions of this Sentsubu 2 are the width of the I core 0.3
Total width including 4m-1.1m, width 1.8iu+
, thickness 0.6--.

Next, this chip 2 was inserted into the groove 3 on one medium outflow end side of the slide rail 1a of the ceramic slider 1 made of calcium titanate, and SiO□-8203- with a softening point of 445°C and a melting temperature of 540°C was inserted. Pb0 series contact if
After bonding with f laths, final finishing was performed to obtain a composite magnetic head similar to that shown in FIG. 5(c).

The composite magnetic head 5 to head (A) of the present invention manufactured as described above and the Sendust thin film 5 are attached to the front gap portion 2.
Formed on both sides of the gear part forming surface 2e12e' of d (B), Formed on the surface 2e on the C core 2a side (C)
, for the one (D) in which the Sendust thin film 5 was not formed on any surface, what are the characteristics of each magnetic field? The results of the test with Tochistar are shown in Figure 3.

As is clear from FIG. 3, the device (A) of the present invention is superior to the other devices (B), (C), and (D) in both resolution and output.

xjr17-Taitohi n's 1. FIG. 4 shows the results of tests conducted with different thicknesses of the sendust thin film.

As seen in Figure 4, in order to obtain the desired output,
A film thickness exceeding 10 μm is required, but if it exceeds 10 μm, peeling or cracking will occur, making it unusable.

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

In the above embodiment, the chip 2 with the step portion 2s formed on the left side as shown in the Pt51 figure (b) is inserted into the groove 3 on the left side of the slider 1 as shown in the fJS5 figure (a), and the chip 2 is bonded. Although the explanation has been given for the upside version, the same effect can be obtained for the downside version in which a chip with a step portion formed on the right side is inserted into the right groove and bonded.

〔Effect of the invention〕

As described above, the composite magnetic head of the present invention has excellent magnetic properties, has a low rate of film peeling and cracking, and is highly reliable.

[Brief explanation of the drawing]

FIG. 1(a) is a front view of a chip showing an embodiment of the present invention, FIG. 1(b) is a side view of the same, FIG. 2 is a front view of the chip showing a state before joining, FIG. Figure 4 shows the results of tests on magnetic thin films, Figures 5 (a), (b),
(c) is a diagram showing an example of a conventional composite magnetic head;
(a) is a perspective view showing the slider, (b) is a chip, and (c) is a perspective view showing an assembled state, respectively. Figure 6 is a perspective view showing an exaggerated main part of the conventional one. 1: Nislider, 2: Chip, 3: Groove,
4: lath, 4a: bonded glass, 4b:
Reinforcement lath, 4C: Adhesive lath, 5: Sendust thin film, 6: 5iOz thin film, 1a Varnish ride rail, 2a: C core, 2b: 1 core, 2C: Winding groove, 2d: Front gap, 2e %
2e': Gear part forming surface, 2f: Back gap part, 2g52g': Gap part forming surface, 2h:
Media facing surface, 2s Ni-step part, Gd: Gear depth, d Depth of Ni-step part Agent Patent attorney Honma Matsuri 2 Figure 3 Figure 3, Figure 4 Figure 4 (nm)

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 with a thickness of 1 to 10 μm is formed only on the surface forming the front gap portion and back gap portion of the I core, and on the thin film surface and the surface of the C core facing this surface. A SiO_2 thin film and a glass thin film are sequentially formed on both sides or either side of the surface to join the C core and I core, and further on the side facing the magnetic recording medium from the gap depth of the front gap part. 1. A composite magnetic head having a deep step portion formed therein, wherein 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.