JP2888468B2 - Magnetic head and method of manufacturing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic head and a method of manufacturing the same, and more particularly to a VTR (Video Tape Rec).
The present invention relates to a magnetic head comprising a soft magnetic thin film used for forming a magnetic circuit and a non-magnetic substrate supporting the soft magnetic thin film, and particularly to a method for manufacturing a magnetic head for a narrow track.

[0002]

2. Description of the Related Art High coercivity media such as metal tapes have become mainstream with the increase in the density of magnetic recording technology. At present, core materials used in magnetic heads have high saturation magnetic flux densities. Has been requested. Under such circumstances, a head chip having a soft magnetic thin film 31 having a high saturation magnetic flux density and a non-magnetic substrate 32 supporting the soft magnetic thin film 31, as shown in FIG. ing. On the other hand, in a magnetic head for a narrow track, if the thickness of the soft magnetic thin film is simply reduced to a size corresponding to the track width, the magnetic resistance of the head core made of the soft magnetic thin film increases, and the performance of the magnetic head decreases. . Therefore, as shown in FIG. 15 or FIG.
A head chip in which the thickness of 1) is reduced only near the magnetic gap 43 (53) is used.

FIGS. 17 (a) to 17 (i) are views schematically showing a process of manufacturing the magnetic head for the narrow track. First, a substantially V-shaped groove is machined in a non-magnetic substrate (FIG.
(B)) A soft magnetic thin film having a thickness equal to or larger than the track width is formed on the previously processed V-shaped groove (FIG. (C)). Thereafter, the soft magnetic thin film in the vicinity of the magnetic gap is removed by etching or machining until the film thickness becomes equivalent to the track width (FIG. 4D), and then the core pieces 44 (54) are joined together. 4 used for bonding
5 (55) is filled (FIG. (E)), and excess bonding agent is ground and polished (FIG. (F)). A pair of the core pieces obtained in this manner is prepared (FIG. (G)), and the gap surface 46 thereof is provided.
(56) The core pieces are joined to each other so as to face each other (FIG. (H)), and the core 47 (57) thus obtained is cut to obtain a head chip (FIG. i)).

FIGS. 18 and 19 show details of the difference in the step of removing the unnecessary portion of the soft magnetic thin film due to the difference in the shape of the head chip shown in FIGS. In FIG. 18, a diamond blade 48 having a trapezoidal cross section from the direction of the film forming surface is shown.
In FIG. 19, the soft magnetic thin film is removed from the substrate side by a diamond blade 58 having a rectangular cross section.

[0005]

First, the problems in the processing method shown in FIG. 18 will be described with reference to FIG. FIG.
FIG. 19 is a diagram in which wear of the diamond blade 48 used in FIG. 18 is emphasized. Diamond blade 48 is a ~
As a result of removing unnecessary portions of the soft magnetic thin film 41 in the order of d, if only a portion of the soft magnetic thin film 41 is worn away,
There is a difference of f only in the film thickness load near the gap of d. It is known that such wear of the diamond blade 48 is corrected by increasing the cutting depth. However, it is necessary to work to find the average value of the wear amount, which is very troublesome. Based on the fact that it travels faster in the height direction than in the direction, the processing method of FIG. 19 is performed. In FIG. 19, as shown in FIG. 21, the film thickness in the vicinity of the gap is controlled only by the cutting position of the diamond blade 58. Therefore, even if the wear of the diamond blade 58 in the height direction progresses, the film thickness in the vicinity of the gap is increased. Has the advantage that it is not affected.

Next, problems in the processing method shown in FIG. 19 will be described with reference to FIG. FIG. 22 is a diagram illustrating a step of removing the surplus bonding agent when the processing method of FIG. 19 is selected, in which an error in the removal amount is emphasized. In FIG. 22, an error in the height of the gap surface i occurs between the two substrates g and h attached to one jig due to the accumulation of processing errors such as variations in the adhesive layer 59. . When the gap surface is polished in this state, an error of only j occurs in the track widths of g and h. In addition, if there is an error of k in the amount of processing in the grinding and polishing steps of the gap surface, an error of m will occur even if the substrates are attached at the same height. Here, FIG.
In the case of using the processing method No. 8, as shown in FIG. 23, even if a considerable error occurs in the bonding agent removing step, the track width is not affected. In summary, when the processing method of FIG. 18 is selected, the excess soft magnetic thin film is removed in the step of removing, and when the processing method of FIG. Since the width change is very sensitive, it is very difficult to control the track width.

[0007] The present invention has been made in view of such circumstances, and in order to obtain a magnetic head having a narrowed-down structure, a V head is required.
It is an object of the present invention to provide a magnetic head and a method of manufacturing the same, in which a groove is formed in an inverted crank shape so as to reduce a change in track width due to a change in a cut amount when polishing a gap surface during a narrowing process.

[0008]

According to the present invention, there is provided a magnetic head comprising: (1) a soft magnetic thin film constituting a magnetic circuit; and a non-magnetic substrate for supporting the soft magnetic thin film. The angle α between the soft magnetic thin film near the gap and the gap surface and the angle β between the soft magnetic thin film other than near the gap and the gap surface satisfy the relationship β <α <180 ° −β, and The film thickness in the vicinity of the gap is smaller than the film thickness other than in the vicinity of the gap, or (2) a method of manufacturing a magnetic head comprising a soft magnetic thin film constituting a magnetic circuit and a non-magnetic substrate supporting the soft magnetic thin film When forming a slope on which a soft magnetic thin film is formed on a non-magnetic substrate, the slope is formed such that the angle of the slope near the gap surface to the gap surface is closer to a right angle than a portion other than the vicinity of the gap surface. Form soft magnetic thin film After, in which was characterized by removing an unnecessary portion of the soft magnetic thin film in the vertical direction from the direction of the gap surface.

[0009]

When forming a slope on which a soft magnetic thin film is formed on a non-magnetic substrate, the slope is formed such that the angle of the slope near the gap surface to the gap surface is closer to a right angle than the portion other than the vicinity of the gap surface. After forming the soft magnetic thin film, unnecessary portions of the soft magnetic thin film are removed in a direction perpendicular to the direction of the gap surface. With such a configuration, the angle between the soft magnetic thin film and the gap surface near the gap surface is a right angle, and the film thickness near the gap surface is constant. The fluctuation of the track width due to the fluctuation of the cutting depth in the removing step is completely eliminated.

[0010]

Embodiments will be described below with reference to the drawings. FIG. 1 is a block diagram for explaining one embodiment (embodiment 1) of a magnetic head according to the present invention. In the drawing, 1 is a soft magnetic thin film, 2 is a non-magnetic substrate, 3 is a magnetic gap, and 4 is a core. Piece 5 is a bonding agent. The outline of the manufacturing process of the magnetic head is the same as that of FIG. 17 described above, and the reference numbers in FIG. 17 are 41 → 1, 42 → 2, 43 → 3, 44 →
4, 45 → 5 respectively. The magnetic head of the present invention includes a soft magnetic thin film 1 constituting a magnetic circuit and a non-magnetic substrate 2 supporting the soft magnetic thin film 1. The angle α between the soft magnetic thin film 1 near the gap and the gap surface (<90
°) and the angle β between the soft magnetic thin film 1 and the gap surface other than near the gap satisfies the following relationship. β <α <180 ° −β Moreover, the film thickness near the gap is smaller than the film thickness other than near the gap. The soft magnetic thin film 1 is perpendicular to the gap surface in the vicinity of the gap, and extra soft magnetic thin film 1 is removed from the film forming side.

FIGS. 2 to 4 are views showing a method of manufacturing the magnetic head shown in FIG. FIG. 2 shows a non-magnetic substrate after processing a substantially V-shaped groove as a film forming surface. In this embodiment, the processing is performed so that the angle of the film formation surface near the gap surface is a right angle. FIG. 3 is a view showing the non-magnetic substrate after removing an extra soft magnetic thin film after forming the soft magnetic thin film.
Excessive soft magnetic thin film 1 is removed from the film forming side by a diamond blade 8 having a rectangular cross section. Therefore, even if there is abrasion in the height direction of the blade, the track width is not affected. FIG. 4 is a view showing the core piece 4 from which excess bonding agent has been removed after filling with the bonding agent. Since the film thickness near the gap is constant, the track width is not affected even if the removal amount of the bonding agent in the height direction varies.

FIG. 5 is a structural view of another embodiment (embodiment 2) of the magnetic head according to the present invention, in which 11 is a soft magnetic thin film, 12 is a non-magnetic substrate, 13 is a magnetic gap, and 14 is a core. Piece 15 is a bonding agent. The outline of the manufacturing process of the magnetic head is the same as that of FIG. 17 described above, and the reference numbers in FIG. 17 are 41 → 11, 42 → 12, 43 → 1.
3, 44 → 14 and 45 → 15 respectively. The soft magnetic thin film 1 has an angle larger than a right angle with respect to the gap surface in the vicinity of the gap, and extra soft magnetic thin film 1 is removed from the film forming side.

FIGS. 6 to 9 are views showing a method of manufacturing the magnetic head shown in FIG. FIG. 6 is a view showing the non-magnetic substrate after processing a substantially V-shaped groove which is a film formation surface. In this embodiment, the processing is performed so that the angle of the film formation surface near the gap surface is slightly larger than the right angle. 7A to 7C show an example of a specific processing method in the case of performing groove processing using a dicing saw in the present embodiment. FIG.
As shown in FIG. 6, by forming a jig for attaching the non-magnetic substrate 12 at a predetermined inclination and changing the cutting amount of the diamond blade 18, a film-forming surface having the shape shown in FIG. 6 can be obtained.

FIG. 8 is a view showing the non-magnetic substrate after removing the excess soft magnetic thin film after forming the soft magnetic thin film. Excessive soft magnetic thin film 11 is removed from the deposition side with a diamond blade having a rectangular cross section. Therefore, even if there is abrasion in the height direction of the blade, the track width is not affected. FIG. 9 is a diagram showing the core piece 14 from which the excess bonding agent has been removed after filling with the bonding agent. Since the film thickness in the vicinity of the gap is almost constant, even if there is a change in the removal amount of the bonding agent in the height direction, the influence on the track width is small.

FIG. 10 is a structural view of still another embodiment (embodiment 3) of a magnetic head according to the present invention. In the drawing, reference numeral 21 denotes a soft magnetic thin film, 22 denotes a non-magnetic substrate, 23 denotes a magnetic gap,
Is a core piece and 25 is a bonding agent. The outline of the manufacturing process of the magnetic head is the same as that of FIG.
21, 42 → 22, 43 → 23, 44 → 24, 45 → 2
5 respectively. The soft magnetic thin film 21 has an angle smaller than a right angle with respect to the gap surface in the vicinity of the gap, and excess soft magnetic thin film 21 is removed from the substrate side.

FIGS. 11 to 13 are views showing a method of manufacturing the magnetic head shown in FIG. FIG. 11 is a diagram showing the non-magnetic substrate after processing a substantially V-shaped groove that is a film formation surface. In this embodiment, the processing is performed so that the angle of the film formation surface near the gap surface is slightly smaller than a right angle. FIG.
FIG. 4 is a view showing a non-magnetic substrate after an extra soft magnetic thin film is removed after a soft magnetic thin film is formed. Extra soft magnetic thin film 21
Is removed from the substrate side by a diamond blade 28 having a rectangular cross section. Therefore, even if there is abrasion in the height direction of the blade, the track width is not affected. FIG.
Are core pieces 24 from which excess bonding agent has been removed after filling with bonding agent.
FIG. Since the film thickness in the vicinity of the gap is almost constant, even if there is a change in the removal amount of the bonding agent in the height direction, the influence on the track width is small.

[0017]

As is apparent from the above description, the present invention has the following effects. That is, when forming a slope on which a soft magnetic thin film is formed on a non-magnetic substrate, the slope is formed such that the angle of the slope near the gap surface with respect to the gap surface is closer to a right angle than a portion other than the vicinity of the gap surface. After the soft magnetic thin film is formed, unnecessary portions of the soft magnetic thin film are removed in a direction perpendicular to the direction of the gap surface, and the angle between the soft magnetic thin film and the gap surface near the gap surface is more perpendicular than near the gap surface. , And thus the change in the film thickness near the gap surface is smaller, so that the variation in the track width due to the variation in the cutting depth in the step of removing the excess soft magnetic thin film and the step of removing the excess bonding agent is reduced, Therefore, there is a great effect in improving the yield.

[Brief description of the drawings]

FIG. 1 is a configuration diagram for explaining an embodiment (Embodiment 1) of a magnetic head according to the present invention.

FIG. 2 is a view of the substrate after the processing of the film forming surface according to the first embodiment of the present invention viewed from the sliding surface direction.

FIG. 3 is a view of a substrate from which a film forming surface and an excess soft magnetic thin film have been removed according to Example 1 of the present invention when viewed from a sliding surface direction.

FIG. 4 is a view of the core piece after filling of the bonding agent and removal of the excess bonding agent according to the first embodiment of the present invention viewed from the sliding surface direction.

FIG. 5 is a configuration diagram of another embodiment (Embodiment 2) of the magnetic head according to the present invention.

FIG. 6 is a view of a substrate on which a film forming surface has been processed according to a second embodiment of the present invention, viewed from a sliding surface direction.

FIG. 7 is a diagram illustrating a method of forming a film formation surface according to a second embodiment of the present invention.

FIG. 8 is a view of the substrate from which the film formation and the removal of the excess soft magnetic thin film of Example 2 of the present invention have been completed, as viewed from the sliding surface direction.

FIG. 9 is a view of a core piece after filling with a bonding agent and removing excess bonding agent according to a second embodiment of the present invention, viewed from a sliding surface direction.

FIG. 10 is a configuration diagram of still another embodiment (embodiment 3) of the magnetic head according to the present invention.

FIG. 11 is a view of a substrate on which a film forming surface has been processed according to a third embodiment of the present invention, viewed from a sliding surface direction.

FIG. 12 is a view of the substrate from which the film formation and the removal of the excess soft magnetic thin film of Example 3 of the present invention have been completed, as seen from the sliding surface direction.

FIG. 13 is a view of the core piece after filling of the bonding agent and removal of the excess bonding agent according to the third embodiment of the present invention viewed from the sliding surface direction.

FIG. 14 is a configuration diagram of a conventional magnetic head.

FIG. 15 is another configuration diagram of a conventional magnetic head.

FIG. 16 is a configuration diagram of still another conventional magnetic head.

FIG. 17 shows a conventional example and the first embodiment shown in FIGS. 15 and 16;
FIG.

18 is a diagram showing a main part of the conventional processing method shown in FIG.

19 is a diagram showing a main part of the conventional processing method shown in FIG.

20 is a diagram showing a problem of the conventional processing method shown in FIG.

21 is a diagram showing a problem of the conventional processing method shown in FIG.

FIG. 22 is a diagram showing advantages of the conventional example shown in FIG. 16 with respect to the problems of the conventional processing method shown in FIG. 15;

FIG. 23 is a view showing advantages of the conventional example shown in FIG. 15 with respect to the problems of the conventional processing method shown in FIG. 16;

[Explanation of symbols]

1: Soft magnetic thin film, 2: Non-magnetic substrate, 3: Magnetic gap,
4 core piece, 5 bonding agent, 6 gap surface, 7 core,
8: diamond blade, 9: adhesive layer.

Claims (2)

(57) [Claims] In a magnetic head comprising a soft magnetic thin film constituting a magnetic circuit and a non-magnetic substrate supporting the soft magnetic thin film, an angle α formed between the soft magnetic thin film near the gap and the gap surface, and an angle other than near the gap. Wherein the angle β between the soft magnetic thin film and the gap surface satisfies the relationship β <α <180 ° −β, and the film thickness near the gap is smaller than the film thickness other than near the gap. Magnetic head. 2. A method of manufacturing a magnetic head comprising a soft magnetic thin film constituting a magnetic circuit and a non-magnetic substrate supporting the soft magnetic thin film, wherein a slope for forming the soft magnetic thin film on the non-magnetic substrate is formed. In doing so, the slope is formed such that the angle of the slope near the gap surface to the gap surface is closer to a right angle than the portion other than the vicinity of the gap surface, and after forming the soft magnetic thin film, the slope is perpendicular to the direction of the gap surface. A method of manufacturing a magnetic head, comprising: removing an unnecessary portion of a soft magnetic thin film in a direction.