JP2887204B2 - Method of manufacturing narrow track magnetic head - Google Patents

Description

The present invention relates to a magnetic head used for a VTR, a floppy disk drive, a hard disk drive, etc.
The present invention relates to a method for manufacturing a magnetic head formed by bonding a soft magnetic core on a non-magnetic substrate.

2. Description of the Related Art In recent years, with the increase in density of magnetic recording media such as magnetic disks and magnetic tapes, magnetic heads that record information on the magnetic recording media and reproduce information from the magnetic recording media have been developed.
The track width is becoming narrower.

In particular, when the track width is 10 μm or less, it is difficult to increase the track width by machining with a dicing saw or the like. As a magnetic head for realizing a narrow track width, for example, a thin-film laminated magnetic head has been embodied.

A specific example of this thin-film laminated magnetic head will be described with reference to FIG. In FIG. 3, 1 is a bulk type core chip,
A pair of cores 2a and 2b are joined and integrated with a non-magnetic adhesive material, for example, glass 3. The top end surface of the core chip 1 is formed into an arcuate curved surface having a predetermined curvature in order to smoothly contact a magnetic recording medium such as a magnetic tape, and
A magnetic gap g having a predetermined track width Tw is formed above the joint surface between the cores 2a and 2b with a nonmagnetic thin film 4 such as SiO ₂ interposed therebetween. Further, the core chip 1 is formed by joining and integrating the cores 2a and 2b by forming winding grooves 5a and 5b formed on the outer surface of the cores 2a and 2b and concave grooves on the inner surface of the core 2a. Using the wound winding insertion hole 6 to core the wire 7 of the insulation coating treatment
A predetermined number of turns are wound around 2a and 2b to form a coil. still,
The cores 2a and 2b have a predetermined track width Tw of a magnetic gap g between non-magnetic substrates 2 'and 2' made of ceramic, glass or the like.
And a soft magnetic film 2 ″ made of Sendust, Permalloy, or the like having the same thickness as that of FIG.

Next, a conventional example of a method for manufacturing the magnetic head will be described with reference to FIG.
A description will be given based on FIGS.

First, as shown in FIG. 4a, a non-magnetic substrate 8a of a rectangular parallelepiped shape such as ceramic or glass is prepared, and a soft magnetic film 8 ″ such as sendust or permalloy is formed on the non-magnetic substrate 8a with a track width Tw. Next, as shown in Fig. 4b, a desired number of cores of the formed non-magnetic substrate 8a are prepared, and a laminated block body is formed with an adhesive or an adhesive glass as shown in Fig. 4b. 9a and then the fourth
As shown in FIG. C, the winding locking groove 10a and the winding insertion and magnetic path forming medium groove 11a are formed by cutting. Here, similarly, except for the middle groove 11a, the same structure is omitted because it has the same structure, but the other laminated block body 9b is also formed. Then, after forming a gap spacer film equal to the magnetic gap length on at least one of the magnetic gap forming butting surfaces of the stacked block body, the stacked block bodies 9a and 9b are butted as shown in FIG. Glass is welded and integrated with the embedded adhesive glass 12 provided. And the magnetic gap g
When the upper surface, that is, the medium-corresponding surface is polished to a curved surface as indicated by a dashed line 13 and sliced in parallel to the direction of fine lines 14, 14,..., The core for a magnetic head having a narrow track width shown in FIG. Can be Then, through a coil winding operation, a magnetic head as shown in FIG. 3 is obtained.

Problems to be Solved by the Invention Meanwhile, in the above-described method of manufacturing a magnetic head, the track width depends on the film thickness by sputtering or the like. However, there is a problem in that it is difficult to accurately form a track width due to a variation in film thickness and a variation in abutting alignment, resulting in a decrease in the quality of a magnetic head and a lack of reliability.

Means for Solving the Problems The present invention has been proposed in view of the above problems, and has a soft magnetic core bonded and integrated on a non-magnetic substrate. With a magnetic head obtained by polishing this soft magnetic core to a predetermined track width, the soft magnetic core is manufactured in advance to have a predetermined track width or more and polished.

According to the above technical means, the track width is determined by the polishing accuracy, and the variation in the film thickness and the alignment accuracy are not related, so that a highly accurate track width can be obtained.
Further, since there is no track deviation or the like, the disturbance of magnetic flux generated at the track end, that is, the fringing effect is small, and the guard band width can be reduced to increase the track density.

Embodiment An embodiment of a magnetic head according to the present invention will be described with reference to FIGS.

First of all, before the description, a feature of the present invention is that a soft magnetic core is formed to be thicker than the track width in advance, and the soft magnetic core is attached to a non-magnetic substrate so that the soft magnetic core has a track width. Is to grind up.

In this embodiment, first, as shown in FIG. 2A, a pair of soft magnetic materials, for example, core blocks 1a and 1b made of ferrite, sendust, amorphous, or the like are prepared, and the inner block 1a is provided in one block 1a. Perform winding groove processing. The gap forming surfaces 1c of the pair of core blocks 1a and 1b are polished with high precision and mirror-finished. Thereafter, a nonmagnetic film such as SiO ₂ having a film thickness equal to the gap length is formed on the bonding surface, and the bonding surfaces of the core blocks 1a and 1b are bonded to each other as shown in FIG. , 3 'are embedded and matched. The butted core blocks are pressed with a jig or the like, and the upper glass 3 and the lower glass 3 'of the inner winding groove are thermally bonded in a furnace. One side 1a of the sliced core chip 1 is pre-polished as shown by a broken line 4 in order to make this block Tw 'equal to or more than the track width Tw. A non-magnetic adhesive such as glass or an organic adhesive is applied to the polished surface 1d and applied by sputtering or the like. If glass, the non-magnetic substrate 2 and the core chip 1 are thermally welded in a furnace by pressing with a jig. To adhere. The opposite side of the joined surface of the magnetic head core chip, that is, the exposed surface is polished so that the thickness of the core chip becomes the track width Tw. If necessary, a non-magnetic substrate is bonded to the polished surface of the core chip with glass or an organic adhesive. The top end surface of the magnetic head is tape-wrapped, and a winding operation is performed to obtain a magnetic head having a narrow track width similar to that shown in FIG. The non-magnetic substrate may be provided with an inner winding groove on a single substrate by etching, laser processing, electric discharge processing or the like.

According to the present invention, the track width Tw of the magnetic gap portion is
Can be processed with a polishing lap accuracy, so that the track width can be accurately set.

Furthermore, since there is no track deviation between a pair of core chips in principle, in the case of a recording method in which guard band tracks such as FDD and HDD exist, it is possible to provide a high-quality and highly reliable magnetic head with a small fringing effect. it can.

[Brief description of the drawings]

FIG. 1 is a perspective view of a magnetic head core according to the present invention, and FIG.
FIGS. A, b, and c are perspective views of a core showing a method of manufacturing a magnetic head according to the present invention, FIG. 3 is a perspective view showing a conventional example of a thin-film laminated magnetic head, and FIGS. FIG. 7 is a perspective view of a core showing a method for manufacturing the same. 1 ... soft magnetic core, 2 ... non-magnetic substrate, Tw ... track width, Tw '... thickness greater than track width.

Claims (1)

(57) [Claims] 1. A soft magnetic core having a thickness equal to or more than a predetermined track width is previously adhered on a non-magnetic substrate with its preliminary polished surface, and then the soft magnetic core is polished to a track width and / or the core thickness is reduced. And a method of manufacturing a narrow track magnetic head having a soft magnetic core on a non-magnetic substrate.