JPH04188416A - Manufacture of magnetic head - Google Patents

Abstract

PURPOSE:To obtain a stable gap by forming a rectangular resist pattern in the exposed sectional width of a laminated magnetic core section on the gap forming surface of a magnetic-core half body, etching the magnetic core section and defining a specified track width. CONSTITUTION:A specified resist pattern 24 is formed to the laminated magnetic core section 5 of at least one magnetic core half body member 20a of magnetic core half body members 20a, 20b through a photolithographic technique, and ion beam etching is executed according to the resist pattern 24. The total thickness Z of the laminated magnetic core section 5 is set previously at a value slightly larger than desired track width W at that time, and the rectangular resist pattern 24 is arranged so that a track-width regulating section to be left after etching is kept in the total thickness Z or the laminated magnetic core section 5 and the magnetic core section 5 is etched. Accordingly, the strength of a gap junction and the dimensional accuracy of gap length can be improve without being subject to the effect of the stepped section at a boundary section between a reinforcing substrate and the laminated magnetic core section.

Description

DETAILED DESCRIPTION OF THE INVENTION (A) Field of Industrial Application The present invention relates to a magnetic head used in a magnetic recording/reproducing device such as a VTR.

(b) Conventional technology In magnetic recording and reproducing systems such as VTRs, it is desirable to improve temporal recording density (higher frequency band) and spatial recording density (narrower tracks, shorter wavelengths). ing. To achieve this, a magnetic head with a narrow gap and a magnetic core with a high saturation magnetic flux density must be moved in relative sliding motion at high speed to record/reproduce on a high coercive force medium capable of recording at short wavelengths. is the premise.

As a magnetic head for such high-density magnetic recording, for example, Japanese Patent Publication No. 1-312713 (GLIB 5
A magnetic alloy film laminated core type head such as that disclosed in No. 2003/147) is promising (see FIG. 5).

FIG. 5 is an external perspective view of this magnetic head, and FIG. 6 is an enlarged front view of its medium sliding surface.

In the figure, a magnetic head (1) includes a magnetic core half (2) in which a laminated magnetic core part (and) as a main magnetic path is formed;
The magnetic conductors are bonded to each other via a non-magnetic material (not shown) such as, for example, Sin.

This laminated magnetic core part (mutual) is made of a magnetic alloy material with a high saturation magnetic flux density in order to be compatible with a medium with a high coercive force.

Generally, the magnetic properties of thick magnetic alloy materials deteriorate due to the influence of eddy currents at high frequencies. To prevent this, as shown in Figure 6, a non-magnetic substrate (2a) such as ceramic is used.
Relatively thin magnetic alloy films (3a), (3b), (
3c), (3d) and electrical insulating films (4a), (4b
), (4C) are alternately laminated to form a magnetic core part (dan), and then a reinforcing substrate (2a') is heat-pressed through an adhesive glass layer (6) to form a pair of magnetic core halves. body (2),
(2') is obtained. Note that (8) indicates a gap.

Furthermore, the laminated magnetic head (1) shown in Fig. 5 can solve the problem of high-speed sliding with the medium by using a ferrite nest type as shown in Fig. 7(a) or a ferrite nest type as shown in Fig. 7(b). This magnetic head is advantageous in that it has a magnetic core structure that does not include a ferrite material (9) that tends to generate sliding noise, compared to the ferrite/magnetic alloy film composite magnetic head shown in FIG. In FIG. 7, (10) indicates a bonding glass, and (11) indicates a magnetic alloy film.

(c) Problems to be Solved by the Invention The gap portion (8) of the laminated head (±) shown in FIG. ) and an adhesive glass layer (6) on the other side (see Figure 8a) are stacked together and heat-pressed to form a magnetic field as shown in Figure 8(b). After forming the core half members (20a) and (20b) and mirror-polishing the gap forming surfaces (21a) and (21b) of the magnetic core half members (20a) and (20b), Sin.

It is formed by butt joining via a gap spacer (not shown) such as the like.

By the way, the above-mentioned gap forming surface (21a), (21
When b) is mirror-polished, a step (δ) as shown in Fig. 8(c) is created at the boundary between the non-magnetic substrate (2a) and the laminated magnetic core (and) due to the difference in hardness and grindability between the two. ) occurs.

A pair of magnetic core half members (20a) and (20b) in which such a step (δ) exists is connected to a gap spacer (2).
2), a hollow portion (23) as shown in FIG. 8(d) is created in the magnetic gap, resulting in a magnetic gap that is unstable in terms of bonding strength.

In fact, when we prototyped a magnetic 7-doped (1) as shown in Figure 1#5, when mirror-polishing the gap-forming surface, the non-magnetic substrate (
Crystallized glass) and laminated magnetic core part (Sendas)/SiO
The step difference (δ) generated at the boundary with +) is approximately 0.05μ
0.15 μm thick as a gap spacer
810. By forming a film, the above-mentioned FIG. 8(d)
), the gap length including the hollow part (23) is 0.2
Although the aim was to set the gap length to 5 am, the dimensional accuracy of this gap length is not reliable, and the recording and reproducing characteristics as a narrow gap magnetic head for high-density recording cannot be guaranteed.

(d) Means for Solving the Problems The method for manufacturing a magnetic head according to the present invention has a structure in which a laminated magnetic core portion formed by laminating multiple layers of magnetic alloy films with electrically insulating films interposed therebetween is sandwiched between reinforcing substrates. When gap-joining a pair of magnetic core halves having a non-magnetic material through a non-magnetic material, the exposed cross-sectional width of the laminated magnetic core portion on the gap-forming surface of the magnetic core halves is bonded by 7 otolithography technology. This method is characterized in that a rectangular resist pattern is formed, and etching is performed by irradiation with an ion beam or the like according to the resist pattern to define a predetermined track radius.

(e) Effect According to the method for manufacturing a magnetic head of the present invention, since the laminated magnetic core portion is present on the gap forming surface of at least one magnetic core half and protrudes from the reinforcing substrate surface, the magnetic core of the elbow When the halves are gap-joined through a non-magnetic material, the laminated magnetic core portion is not affected by the step (δ) that occurs during mirror polishing, and the laminated magnetic core portion is in close contact with the gap spacer (non-magnetic material). be combined.

(F) Example Hereinafter, a specific example of the present invention will be described in detail with reference to the drawings. Note that the same parts as in the conventional example are given the same reference numerals, and the explanation thereof will be omitted.

FIG. 1 shows an enlarged view of the main part of the medium sliding surface of a magnetic head to which the present invention is applied. In the figure, the magnetic head (±) has a pair of magnetic core halves (200) and (200') with a thickness of 0.
．． Gap bonding is performed via a nonmagnetic material (22) of 25 μm 5iOz film.

The magnetic core half (part) has an electrically insulating film (SiO! film with a thickness of 01 μm) on a reinforcing substrate (crystalline glass plate 02a).
(4a,), (4b), (4c) formed of a magnetic alloy film (5 μm thick x 4 layers of Sendust alloy film) (3a), (3b), (3c), (3d). A reinforcing substrate (crystalline glass plate) (2a') is further attached to the laminated magnetic core parts (mutually) via an adhesive glass layer (6).
It has a structure in which the parts are bonded under heat and pressure.

Next, embodiments of the manufacturing process of the magnetic head of the present invention will be described with reference to FIGS. 2(a) and 2(b). FIG. 2(a) shows the magnetic core half members (20a), (20
b) At least one magnetic core half member (20a
This figure shows a state in which a predetermined resist pattern (24) is formed on the laminated magnetic core part (Dan) of a laminated magnetic core part (Dan) using 7 otolithography technology. As shown in FIG. 2(b), a magnetic core half member (20a') having a shape extended by the track width (W) is obtained.

1 here! The important thing is that the total thickness of the laminated magnetic core (and
Z) is set slightly larger than the desired track width (W), and the track width regulating portion that should remain after etching is
Etching is performed by arranging a rectangular resist pattern (24) so as to fit within the total thickness (Z) of the laminated magnetic core part (tan).

In addition, it is possible to simultaneously etch the reinforcing substrate (2a) and the laminated magnetic core part (2), which are made of significantly different materials, and to remove the reinforcing board (2a) and the laminated magnetic core part (21) that are exposed after etching.
The well-known ion beam etching method is suitable as an etching method that does not leave any mechanical or chemical damage on the surface to be etched (and).

Although it is possible to form the structure near the gap by machining using a rotary grindstone or the like without using the etching method as in the present invention, it is possible to simultaneously process the reinforcing substrate and the laminated magnetic core, which are made of significantly different materials, with high precision. It's not easy.

A pair of magnetic core half members (20a
'), (20b) are heated and pressed with a bonding glass (10) via a gap spacer (22), and subjected to prescribed processing to obtain a magnetic head (±) (see FIG. 1).

The magnetic head (±) obtained by the magnetic head manufacturing method of the present invention includes a reinforcing substrate (2a) produced during the manufacturing process,
(2a') and the step (
gap spacer (22
), it is superior in terms of the strength of the gap joint and the dimensional accuracy of the gap length.

In addition, in the conventional magnetic head (1) (see Fig. 5), the gap bonding glass (10) is filled only in the part far away from the track part other than the wire-wound tip part, but the gap bonding glass (10) of the present invention In the magnetic head (degree), both side parts of the track part other than the wire-wound tip part, that is, the reinforcing substrates (2a), (2b), (2a'), (2b') produced by the etching process.
), that is, the magnetic core half pair (sen 0), (20
The gap between 0') is also filled with gap bonding glass (10), making the gap bonding stronger.

Furthermore, the track width (W) of the conventional magnetic head (1) is regulated by the total thickness of the laminated magnetic core (Dan), and it is difficult to ensure uniformity of the film thickness during mass production. , the track width (W) of the magnetic head (100) of the present invention is determined by the resist pattern (24) during etching.
Since it is regulated by the shape and dimensions of the track width, it is easy to ensure uniformity of the track width even during mass production.

As the material of the magnetic alloy films (3a) to (3d), in addition to the sendust alloy, a crystalline or amorphous material based on Fe or Co and containing several percent to several tens of percent of additional elements may be used. High saturation magnetic flux density soft magnetic alloys are suitable.

Moreover, when such a manufacturing method is adopted, as shown in FIG.
) and (3d'), (3d') are bonded glass (
10), facing each other in parallel to form a pseudo gap to detect long wavelength signals (low frequency signals) of adjacent tracks, but the etching process If the depth is set to about 1/2 of the recording wavelength of the target low-frequency signal or more (specifically about 2 to 20 μm), the gap length of the pseudo gap section is sufficient. If the ion beam etching process is performed to reach such a depth, the base of the pattern edge will become gentle as shown in Figure 2 (b), and the above-mentioned problems can be avoided. can.

Incidentally, the magnetic head obtained by carrying out the present invention is not limited to the above-mentioned magnetic head (±) (see FIG. 1), but for example, the magnetic head as shown in FIGS. 4(a) to (c) A magnetic head having a medium sliding surface structure is also included.

FIG. 4(a) is an example in which the present invention is applied only to one magnetic core half member (20a), and FIG. 4(b) is an example in which the present invention is applied only to the magnetic core half member (20a) on one side, and FIG.
Azimuth recording where /' is tilted with respect to the media sliding direction (P)
In the reproduction magnetic head (υsu,), the laminated magnetic core part (and)
In an example where the formation plane of is perpendicular to the gap (8), the same (
C) The figure shows an azimuth recording/reproducing magnetic head (■) in which the gap (8) is inclined with respect to the medium sliding direction (P), and the forming surface of the laminated magnetic core part (and) is inclined with respect to the medium sliding direction (P). Examples are shown that are parallel to P).

(g) Effects of the invention According to the present invention, bonding strength or gap length accuracy,
It is possible to manufacture a magnetic alloy laminated core type magnetic hend having a gear 7 part that is stable in terms of track width accuracy.

[Brief explanation of drawings]

FIG. 1 is an enlarged view of the main part of the medium sliding surface of the magnetic head of the present invention;
2(a) to 2(b) are enlarged views of main parts for explaining the manufacturing process of the magnetic head of the present invention, FIG. 3 is a front view for explaining the magnetic head of the present invention, and FIG. 4(a) ) to (c) are enlarged front views of other specific magnetic heads of the present invention, No. 5
The figure is an external perspective view of a conventional magnetic head, FIG. 6 is a front view thereof, FIGS. 7(a) and (b) are front views of other conventional magnetic heads, and FIGS. 8(a) to (d). ) is a diagram for explaining the manufacturing process of a conventional magnetic head. q4)...Magnetic head, (200)...Magnetic core half, (3a)-(3d)...Magnetic alloy film, (4a)-
(4c)...Electrical insulating film, (and)...Laminated magnetic core portion, (8)...Gap.

Claims (3)

[Claims] (1) A pair of magnetic core halves having a structure in which a laminated magnetic core part formed by laminating multiple layers of magnetic alloy films with electrically insulating films sandwiched between reinforcing substrates is gap-bonded via a non-magnetic material. A method of manufacturing a magnetic head comprising: forming a rectangular resist pattern within the exposed cross-sectional width of the laminated magnetic core portion on the gap forming surface of the magnetic core half by photolithography; A method of manufacturing a magnetic head, the method comprising the step of performing an etching process. (2) The method of manufacturing a magnetic head according to claim 1, wherein the track width of the magnetic head is regulated by the rectangular resist pattern. (3) The method of manufacturing a magnetic head according to claim 1 or 2, wherein the etching process is performed by irradiating an ion beam.