JPH0731778B2 - Method of manufacturing thin film magnetic head - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for manufacturing a thin film magnetic head, particularly a highly efficient thin film magnetic head having a large number of windings.

(Prior Art) FIG. 13 is a cross-sectional view showing the structure of a main part of a thin film magnetic head manufactured by a conventional manufacturing method. In FIG. 13, a conductive material such as Cu is deposited on a substrate 20 made of an insulating material. Coil pattern 21
An insulating layer 22 is formed by filling the upper part of the coil pattern 21 and a gap therebetween with a resin, and a magnetic material such as permalloy is attached from the upper part by vapor deposition or the like to form a lower core 23.

Furthermore, the gap layer 24 and the coil pattern are arranged from above the lower core 23.
An insulating layer 26 is formed of a resin in which 25 is disposed, and an upper core 27 and a protective layer 28 made of a magnetic material such as permalloy are sequentially formed on the insulating layer 26. The thin-film magnetic head obtained by the above-described conventional manufacturing method has a problem that the magnetic circuit of the lower core 23 has irregularities, which deteriorates the magnetic characteristics.

Then, as an improvement of this conventional method, there is a thin film magnetic head having a sectional structure as shown in the fourteenth drawing. The thin film magnetic head shown in FIG. 14 is manufactured as follows.

In FIG. 14, an inverted trapezoidal groove 31 is formed on a substrate 30 made of, for example, ferrite, which is a ferromagnetic material, and A is formed at the bottom of the groove 31.
A coil pattern 32 made of a conductive material such as l, Cu is attached by vapor deposition or the like, and glass, which is an inorganic insulating material, is melted at a predetermined temperature (450 ° C. to 750 ° C.) from the top of the coil pattern 32 to fill the groove 31 with insulation. Layer 33
After forming, the surfaces of the substrate 30 and the insulating layer 33 are made flush with each other by polishing the surface of the substrate 30. After that, a coil pattern 34 of Al, Cu or the like is formed from the upper portion so as to cover the inverted trapezoidal groove, and the nonmagnetic insulating layer 35 is formed from the upper portion.
A magnetic layer 36 made of a ferromagnetic material, such as ferrite, is sequentially formed.

Incidentally, when forming the coil patterns 32 and 34, usually, a photoresist is uniformly applied, covered with a photomask of the pattern, light irradiation and development are performed, a conductor is formed by vapor deposition or the like, and then the remaining photoresist is removed. Use the removal method.

(Problems to be Solved by the Invention) However, also in the conventional example of FIG. 14, after forming the conductive coil pattern 32, the groove 31 is melt-filled from the upper part to the inside of the groove 31. Therefore, the coil pattern 32 depends on the melting temperature of the glass (450 ° C to 750 ° C).
The metal is deteriorated by oxidation, and in extreme cases, there is anger of cutting. Further, since the ferrite of the substrate 30 and the metal of the coil pattern 32 have different coefficients of thermal expansion, the coil pattern may be peeled off depending on the melting temperature of the glass.

On the other hand, since the coil pattern 32 is at the bottom of the groove 31, it is difficult to uniformly apply the photoresist when forming the coil pattern 32. Further, since the photomask is placed on the substrate 30 and exposed, the focus of the exposure pattern is defocused at the bottom of the groove 31. . Due to these reasons, the finish accuracy of the coil pattern 32 is not good, and it is difficult to obtain a large number of coils.

(Means for Solving the Problems) In order to solve the above problems, the present invention fills the groove on the substrate of the ferromagnetic material in which the groove is formed with a non-magnetic inorganic insulating material, and thereafter, The substrate and the insulating material are polished to be in the same plane, a plurality of coil portion grooves are formed on the insulating material corresponding to one groove, and a conductive material is provided in the plurality of coil portion grooves. A method for manufacturing a thin-film magnetic head, characterized in that a substrate on which a coil portion is formed by polishing is ground to be flush with the substrate, and at least a core made of a ferromagnetic material is disposed on the coil portion of the substrate. To do.

(Embodiment) FIGS. 1 to 8 are process diagrams of a first embodiment of a method of manufacturing a thin film magnetic head according to the present invention.

Reference numeral 1 is a substrate made of a ferromagnetic material such as sendust or ferrite, and an inverted trapezoidal groove 2 is formed on the substrate 1 (see FIG. 1). The groove 2 can be processed by diamond cutting by mechanical processing, chemical etching by chemical processing, sputter etching by physical processing, or the like. In the case of a non-magnetic and inorganic insulator 3, for example, lead glass, the groove 2 is melt-filled so as to be slightly higher than the surface of the substrate 1. The insulator 3 is Al ₂ O ₃
Alternatively, SiO ₂ may be formed by vapor deposition or the like. After filling the insulator 3, the surface thereof is polished to make the surfaces of the substrate 1 and the lead glass flush with each other (see FIG. 2).

A photoresist is evenly coated on the substrate 1 polished in this way, covered with a photomask, and a pattern for a coil is drawn on the surface of the insulator 3 through steps such as light irradiation and development. Etc. to form the groove 4 for the lower half of the coil (see FIG. 3). The groove 4 is provided in the longitudinal direction with respect to the groove 2. The number of each groove 4 determines the number of turns of the coil of the magnetic head.

FIG. 4 is a sectional view taken along the line AA of FIG. 3, in which the depth of the groove 4 is d. After processing the groove 4, Al or Cu on the substrate 1
A non-magnetic conductive metal such as is deposited by sputtering or vapor deposition. The thickness of the groove 4 is made larger than the depth d of the groove 4, and then the surface is polished to a mirror finish to be d'which is smaller than the initial depth d of the groove 4 to obtain a surface on the substrate 1. Is flattened to form the coil lower half 5 (see FIG. 5).

Then, a non-magnetic insulating layer (not shown) having a predetermined thickness is formed by sputtering or vapor deposition to form a gap of the magnetic head from above the magnetic head. Then, the core 6 is formed by a known method using a ferromagnetic material such as sendust or ferrite (see FIG. 6). The width 6a of the core 6 is set smaller than the length 5a of the lower coil half 5. Then, an insulating material (not shown) is arranged on the surface of the core 6, and further the coil upper half portion 7 is arranged by a known method. The coil upper half 7 and the coil lower half 5 are arranged so as to wind the core 6, and the coil upper half 7 is connected to the coil lower half 5 in a zigzag shape when viewed from above. (See FIG. 7). FIG. 8 is a sectional view taken along the line BB of FIG.

9 and 10 are schematic process diagrams of a second embodiment of the method for manufacturing a thin film magnetic head according to the present invention. Particularly, a manufacturing example when a coil is wound in a spiral shape, and FIG. FIG. 10 and FIG. 10 are sectional views taken along the plane CC of FIG. 9, respectively.

The manufacturing method is substantially the same as in the case of the first embodiment, and the reverse trapezoidal groove 9 is formed in the substrate 8 made of a ferromagnetic material such as sendust or ferrite as in the case of the first embodiment.
The groove 9 is filled with an inorganic insulating material 10, the surface thereof is made flat, and the spiral grooves 11a and 11b are processed by photoetching or the like. The groove 11a is a portion formed on the insulating material 10 and the groove 11b is a portion directly formed on the substrate 8. Then, a thin film of an insulating inorganic insulating material (not shown) is attached to the groove 11b.

From the top of the grooves 11a and 11b, a non-magnetic conductive metal such as A
The coil 12 is formed by filling the grooves 11a and 11b with l or Cu or the like higher than the groove surface. Then, polish the surface,
The same plane is formed, and a gap layer (not shown) and an upper core 13 made of a magnetic material are sequentially formed.

11 and 12 show a method of manufacturing a base substrate which is different from the above embodiment.

In FIG. 11, 14 is a non-magnetic material, for example, a ceramic plate in which an inverted trapezoidal groove 15 is formed.
A magnetic layer 16 is formed by depositing sendust or the like, which is a ferromagnetic material, on 14 by sputtering or the like. FIG. 12 shows, for example, a part of a substrate 17 (similar to the substrate 1 of FIG. 1) made of an oxide magnetic material such as ferrite, for example, the vicinity of the tape sliding surface is removed, and then the metal magnetic material layer 18 is formed. A substrate is formed of a plurality of magnetic materials that are fixed to each other.

(Effect) According to the manufacturing method of the present invention, since the magnetic circuit has no irregularities and a highly accurate coil pattern can be obtained, the number of turns of the coil can be increased, and accordingly, the value of the current flowing through the coil can be increased. Since the size of the thin film magnetic head is small, problems due to heat generation due to electric current can be solved, and a highly efficient and highly reliable thin film magnetic head can be manufactured.

[Brief description of drawings]

1 to 8 are process drawings of the first embodiment of the method for manufacturing a thin film magnetic head of the present invention, and FIGS. 9 and 10 are the second embodiment of the method of manufacturing a thin film magnetic head of the present invention. 11 and 12 are perspective views of a substrate manufactured by a manufacturing method different from those of the first and second embodiments, and FIGS. 13 and 14 are main parts of a thin film magnetic head manufactured by a conventional manufacturing method. Sectional drawing which shows a structure is shown, respectively. 1,8,17 …… Substrate (magnetic material), 2,4,9,11a, 11b, 15 …… Groove,
3,10 ... Insulator, 5 ... Lower half of coil, 6,13 ... Core,
7 ... coil upper half, 12 ... coil, 14 ... ceramic plate, 16, 18 ... magnetic layer.

Continuation of the front page (56) Reference JP 54-40619 (JP, A) JP 57-113411 (JP, A) JP 57-179927 (JP, A) Actual development 55-128227 (JP , U)

Claims (1)

[Claims] 1. A non-magnetic inorganic insulating material is filled in the groove on a ferromagnetic material substrate in which grooves are formed, and then the substrate and the insulating material are polished to be flush with each other. A plurality of coil part grooves are formed on the insulating material corresponding to one of the grooves, and the plurality of coil part grooves are filled with a conductive material to polish the substrate on which the coil parts are formed to be flush with the same surface. And a core made of at least a ferromagnetic material is disposed on the coil portion of the substrate.