JPH0421915A - Manufacture of magnetic head - Google Patents

Abstract

PURPOSE:To prevent faults caused by clogging or the like and to improve productivity by interposing a magnetic abrasive material between the face of forming a groove and the face of a magnetic pole, working the face of forming the groove by vibrating a substrate and afterwards forming a soft magnetic thin film along the forming face. CONSTITUTION:On a surface 1a of a substrate 1, plural grooves 2 are formed to be adjacent each other. Next, the substrate 1 is inserted between an N mag netic pole 11 and an S magnetic pole 12. At such a time, a magnetic abrasive material 13 in the state of grains is interposed between the face of forming the grooves 2 and the N magnetic pole 11 on the substrate 1. When pressing the substrate 1 in the direction of the magnetic pole 11, the substrate 1 is held by inserting the abrasive material 13 even to the bottom side of the grooves 2. By vibrating the substrate 1 in such a state, a wall surface 5 of the grooves 2 is uniformly polished and smoothly finished by the grains in the magnetic abrasive material 13 to the bottom side. Thus, uniform finishing work after forming the grooves can be executed without depending on dicing work, the various faults caused by clogging can be prevented and the productivity is improved.

Description

Detailed Description of the Invention [Industrial Field of Application] The present invention relates to a magnetic recording and reproducing device such as a video tape recorder, which is composed of a soft magnetic thin film that constitutes a magnetic circuit and a substrate that supports the soft magnetic thin film. The present invention relates to a method for manufacturing a head.

[Conventional technology]

In recent years, with the increase in the density of magnetic recording, high coercive force media such as metal tapes have become mainstream. For this reason,
Core materials used in magnetic heads are also required to have high saturation magnetic flux density.

Therefore, as shown in Fig. 9, for example, to Fe-0-8i
A thin film laminated head is used in which a thin film 32 made of a soft magnetic alloy having a high saturation magnetic flux density, such as a magnetic alloy, is provided on a substrate 31 made of a nonmagnetic material. For the substrate 31, a material with excellent wear resistance, such as crystallized glass, is selected, since the upper end surface 31a in the figure serves as a sliding surface for the magnetic tape.

In the manufacturing process of the above-described magnetic head, for example, by dicing using a blade with a particle size of about 1000, a cross-sectional groove is formed on the substrate 31, as shown in FIG.
After forming continuous letter-shaped grooves 35..., these grooves 3
The above-mentioned soft magnetic thin film 32 is formed on the surfaces 35a of the magnets 5 by vacuum evaporation, sputtering, or the like.

By the way, in order to form the soft magnetic thin film 32 having good magnetic properties, the surfaces 35a... of the grooves 35...
However, it is necessary to have a smooth finish with a surface roughness of, for example, 500 angstroms or less, and for this reason, a further finishing process is performed after the dicing process. As this finishing process, for example, in the lapping process in which the workpiece is pressed against a flat plate-like lapping machine to obtain surface smoothness, in the uneven shape where the grooves 35... are connected as described above, the valley grooves 35... Only the apex part of the series is polished,
Conventionally, it is difficult to obtain a uniform finished surface along the surface 35a of the groove 35 to the bottom side thereof.
After the groove processing by dicing with a blade having a grain size of about 1000, finishing processing is performed by dicing with a cutting depth of 5 μm or less using a high-count blade with a grain size of about 3000, for example, as shown by the broken line in FIG. ing.

[What the invention attempts to solve! Title]

However, as mentioned above, the crystallized glass used as the substrate 31 has poor dicing processability, and for this reason, when finishing dicing using a high-count blade, the amount of cutting per cut is large. This poses a problem in that the blade is likely to become clogged, and as a result, the substrate 31 is likely to be cracked. Furthermore, since clogging is likely to occur as described above, it is necessary to set the machining feed rate to, for example, 0.3 mm/sec or less, and furthermore, it is not easy to process a large number of pieces. As a result, the problem of poor productivity has arisen.

[Means to solve the problem]

In order to solve the above-mentioned problems, a method for manufacturing a magnetic head according to the present invention includes forming grooves of a predetermined shape in a substrate made of a non-magnetic material, and then positioning the groove-formed surface opposite to a magnetic pole surface that forms a magnetic field. The surface of the grooved surface is processed by arranging the substrate, interposing a magnetic abrasive material between the grooved surface and the magnetic pole surface, and vibrating the substrate while pressing the grooved surface toward the magnetic pole surface. The method is characterized in that after that, a soft magnetic thin film is formed along the groove forming surface.

[For production]

According to the above method, the magnetic abrasive material interposed between the groove-forming surface of the substrate and the magnetic pole surface is magnetic not only in the direction along the magnetic pole surface but also in the direction along the direction of the magnetic field approximately perpendicular to the magnetic pole surface. held by suction.

Therefore, by pressing the groove forming surface located at a position opposite to the magnetic pole surface in the direction of the magnetic pole surface, the magnetic abrasive material extending from the magnetic pole surface along the magnetic field direction is also inserted into the bottom side of the groove. Ru. By vibrating the substrate in this state, uniform surface finishing down to the bottom side of the groove is performed.

〔Example〕

The manufacturing process of a magnetic head in one embodiment of the present invention will be explained with reference to FIGS. 1 to 8.

First, as shown in FIG. 2, a plurality of grooves 2 having a cross section of a predetermined pitch dimension A and depth B and having a shape of a square cross section are formed adjacent to each other on the surface 1a of a substrate l having a substantially rectangular parallelepiped shape. They are formed in shapes that extend parallel to each other. As the substrate 1, this substrate 1
Since the surface is the sliding contact surface of the magnetic tape,
For example, a non-magnetic material with excellent wear resistance such as crystallized glass is selected.

The above-mentioned groove processing on the substrate 1 having such wear resistance and therefore high hardness is performed by dicing. In this case, the grooves 2 having the above shape are formed using a blade having a grain size of about 1000.

Next, as shown in FIG. 1, the substrate 1 is inserted between the N magnetic pole 11 and the S magnetic pole 12 that form a DC magnetic field. At this time, pre-granular magnetic abrasive material 13 having a diameter of several microns is interposed between the surface of the substrate 1 on which the grooves 2 are formed and, for example, the N magnetic pole 11 facing this surface. This magnetic abrasive material 1
No. 3 is made by mixing iron particles and alumina particles, for example.

In this state, while pressing the substrate 1 in the direction of the N magnetic pole 11, it is vibrated in a direction perpendicular to the direction of the magnetic field. in this case,
The iron particles in the magnetic abrasive material 13 are arranged on the end face of the N magnetic pole 11,
That is, in a state extending along the direction along the magnetic pole surface as well as the direction of the magnetic field from the N magnetic pole Il to the S magnetic pole 12,
The alumina particles interposed between the iron particles are also held in a similar spatial arrangement by the magnetic attraction. Therefore, by pressing the substrate 1 in the direction of the N magnetic pole 11, the magnetic abrasive material 13 extending from the N magnetic pole 11 along the magnetic field direction is held in the bottom side of the groove 2. By vibrating the substrate 1 in this state, the wall surfaces 5 of the grooves 2, .

After the above, as shown in FIG. 3, Fe-A 1-Si based material is deposited on one smooth surface 5a of each groove wall surface 5 in the valley grooves 2 by vacuum evaporation or sputtering. A soft magnetic thin film 6 made of an alloy is formed to have a thickness of, for example, 20 μm, which approximately corresponds to the track width of the magnetic tape.

After that, as shown in FIG. 4, the valley grooves 2... are filled with low melting point glass 3, and then, as shown in FIG.
The surface of the low melting point glass 3 is polished until it reaches the apex on the surface side of the valley grooves 2 .

Note that at this time, the valley grooves 2 in the soft magnetic thin film 6
. . . are also removed at the same time, and the polished surface 1b has valley grooves 2 adjacent to the surface side apexes extending in a direction perpendicular to the plane of the paper. The 60 layers of the soft magnetic thin film are exposed.

Next, as shown in FIG. 6, the one-sided core block 9
A coil winding window 8 having a recessed groove shape with a trapezoidal cross section is provided on the polished surface lb side, and a coil winding window 7 having a U-shaped cross section is provided on the surface opposite to the polished surface 1b. It is formed. Thereafter, a non-magnetic gap material (not shown) such as SiO□ is deposited on the polished surface lb by vacuum evaporation or sputtering.

As shown in FIG. 7, each of the coil winding windows 7 and 8 and the one-sided core block 9 in which the non-magnetic gap material is formed is attached to the other one-sided core block 9 formed in the same way. The polished surfaces 1b coated with the gap material face each other, and the polished surfaces 1b are polished along the smooth surfaces 5a of the valley grooves 2...
The soft magnetic thin films 6 extending to the core block 15 are fixed under pressure while being positioned on the same straight line, and are bonded to each other to form the core block 15.

Thereafter, the core block 15 is cut out to match the width of the groove 2, thereby producing the head chip 10 shown in FIG. 8. Then, the head depth 10 is adhesively fixed to a base plate (not shown), and further subjected to coil winding and tape polishing to complete the magnetic head.

In this manner, in the above manufacturing method, each of the groove wall surfaces 5...
When forming the soft magnetic thin film 6 along the surface of the groove walls 5, the finishing process to obtain the necessary smoothness (surface roughness of about 500 angstroms or less) is performed using the magnetic abrasive material 13. At the same time, it is arranged in a magnetic field so that the magnetic abrasive material 13 is held in the groove 2 of the substrate 1, and thereby the groove wall surface 5 of the groove 2 is
This allows for uniform finishing down to the bottom side.

Therefore, during the above-mentioned finishing process, various problems caused by clogging of the blade and the like in conventional dicing process can be avoided. Therefore, it is possible to improve productivity compared to the conventional method.

In addition, in the above embodiment, an example in which crystallized glass was used as the substrate l was given and explained, but it is also possible to use photosensitive crystallized glass as this crystallized glass,
Further, the present invention can also be applied when the substrate 1 is made of other non-magnetic materials such as ceramics. Further, in the above description, the magnetic abrasive material 13 was made by mixing iron particles and alumina particles, but it can also be made from other materials such as ferrite particles. Furthermore, in the above description, the N-3 magnetic poles 11 and 12 are opposed to each other and the groove 2 of the substrate 1 is finished in a DC magnetic field, but it is also possible to perform the finishing process in an alternating magnetic field.

〔Effect of the invention〕

As described above, in the method of manufacturing a magnetic head of the present invention, grooves of a predetermined shape are formed on a substrate made of a non-magnetic material, and then the substrate is placed at a position where the groove-formed surface faces a magnetic pole surface that forms a magnetic field. At the same time, a magnetic abrasive is interposed between the groove-formed surface and the magnetic pole surface, and the groove-formed surface is subjected to surface processing by vibrating the substrate while pressing the groove-formed surface in the direction of the magnetic pole surface. , a soft magnetic thin film is formed along the groove forming surface.

Thereby, uniform finishing processing after groove formation can be performed without using conventional dicing processing using a high-count blade. Therefore, compared to the above-mentioned finishing process using dicing, which is likely to cause clogging, various problems caused by clogging can be avoided, and productivity can be improved.

[Brief explanation of drawings]

1 to 8 each show a manufacturing process according to a method for manufacturing a magnetic head according to an embodiment of the present invention. FIG. 1 is a schematic diagram showing the finishing process of the groove wall surface with a magnetic abrasive material. FIG. 2 is a perspective view of the substrate after forming grooves. FIG. 3 is a sectional view of a main part of the substrate after a soft magnetic thin film is formed on the groove wall surface. FIG. 4 is a sectional view of a main part of the substrate after the grooves are filled with low melting point glass. FIG. 5 is a sectional view of the main part of the substrate after the surface side of the low melting point glass has been ground. FIG. 6 is a perspective view of a one-sided core block formed by applying a coil winding window to the substrate after the above process. FIG. 7 is a perspective view of a core block formed by joining the two one-sided core blocks together. FIG. 8 is a perspective view of the magnetic herad tip cut out from the core block. 9 and 10 show conventional examples. FIG. 9 is a perspective view of the Herad tip. FIG. 10 is a cross-sectional view of the main part of the substrate showing groove processing on the substrate during the head chip manufacturing process. 1 is a substrate, 2 is a groove, 5 is a groove wall surface, 6 is a soft magnetic thin film, 11
is an N magnetic pole, and 13 is a magnetic abrasive material.

Claims (1)

[Claims] 1. After forming grooves of a predetermined shape on a substrate made of a non-magnetic material, place the substrate at a position where the groove-formed surface faces the magnetic pole surface that forms a magnetic field, and place the groove-formed surface and the magnetic pole surface The surface of the grooved surface is processed by vibrating the substrate while pressing the grooved surface toward the magnetic pole surface with a magnetic abrasive interposed between the two, and then a soft magnetic thin film is formed along the grooved surface. A method of manufacturing a magnetic head, characterized by: