JPH11213323A - Magnetic head and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inexpensive magnetic head which easily realizes a high-precision track width and is effective even for an effective track width precision, with respect to a narrow track magnetic head of a MIG head having a structure where a soft magnetic alloy thin film is arranged in the vicinity of a gap of a magnetic crustaceous material. SOLUTION: A winding window 5 is formed in core half bodies 1 and 2 which are paired to form the magnetic head and consist of a magnetic crustaceous material, and the gap surface is subjected to specula finishing into a prescribed roughness or lower, and core half bodies 1 and 2 to which soft magnetic alloy thin films 11 and 12 having a prescribed film thickness and a gap member are sputtered are temporarily sealed. Thereafter, electro-discharge machining is performed by an electrode core having a prescribed size to execute the track control corresponding to a system, and glass for core sealing and track reinforcement is fused in track control grooves 8 and 9 formed by electro- discharge machining, thus making a head chip.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for manufacturing a magnetic head suitable for a high-density magnetic recording / reproducing apparatus such as a VHS-VTR and a DVC.

[0002]

2. Description of the Related Art In recent years, magnetic recording technology has been required to have a high frequency characteristic in a video head or the like, and a system capable of recording and reproducing data having a minimum recording wavelength of about 0.5 μm has been required.

Therefore, as a medium for achieving higher density recording, a pure iron-based metal medium (MP tape) and a perpendicular medium having a high coercive force have been developed, some of which are 8 mm VT.
It has been put to practical use in R and DVC.

On the other hand, in a magnetic head, a conventional VTR
It is known that the ferrite head used for such a purpose does not have a saturation magnetic flux density sufficient to magnetize the above medium, and a soft magnetic alloy thin film containing Fe or Co as a main component is used as a main magnetic head. A magnetic head having a path has been proposed and has been put to practical use as a magnetic head with higher efficiency than before.

Hereinafter, a conventional magnetic head and a method for manufacturing the same will be described with reference to the drawings.

FIG. 4 shows a conventional M of a structure in which a soft magnetic alloy thin film is deposited in the vicinity of a magnetic gap of a substrate made of a magnetic hard and brittle material.
FIG. 1 is an overall view showing an IG (Metal in Gap) head, and details in the vicinity of a magnetic gap are shown in a detailed view of a portion B.

The conventional MIG head shown in FIG. 4 serves as a main substrate and is a magnetic hard brittle material (generally, single crystal ferrite).
Having a magnetic gap 42 and a track width (indicated by TW in the figure) formed in dimensions standardized by the magnetic recording system to be mounted on the core halves 40 and 41, and sealing the core halves. Glass 43 to reinforce the truck,
It has a winding window 44 formed in at least one core half.

In the magnetic head, the vicinity of the magnetic gap where structural features are remarkable has a structure shown in a detailed view of a portion B, and the structure is formed at the joint interface between the core halves 45 and 46. The tracks 47 and 48 having the predetermined shapes
Soft magnetic alloy thin films 49 and 50 serving as main magnetic paths and magnetic gap members (omitted in the figure) are applied, positioned with high precision, brought into contact with each other, and sealed with glass 51. The formation of the curved portion 52 depending on the thickness of the thin film at the time of film formation and the sub-micron precision butting at the time of track joining are required.

FIGS. 5 and 6 are process diagrams of the conventional MIG head, and show a method of manufacturing the MIG head shown in FIG. 4 up to the head chip.

FIG. 5 (a) shows core halves 53 and 54 which are made of a magnetic hard and brittle material and serve as a main substrate.
5, 56, at least one core half has a winding window 57
And a mirror surface is polished and finished to a predetermined surface roughness.

FIG. 5 (b) is a diagram showing tracks and shapes formed on the core halves. The track gap shown in the detailed view (cross-sectional view) of the portion C is shown on the magnetic gap surfaces of both core halves. A plurality of grooves 58 are formed at predetermined intervals and depths.

Next, FIG. 5C is a cross-sectional view of a step of forming a main magnetic path and a magnetic gap spacer, and shows a soft magnetic alloy thin film 59 to be a main magnetic path and a magnetic gap member (omitted in the figure). ) Is continuously sputtered to a predetermined thickness in a structure in which a soft magnetic alloy thin film is deposited on the substrate side.

FIG. 5D is a cross-sectional view showing a state in which the core halves are abutted on a track. The affixed track of the soft magnetic alloy thin film and the magnetic gap member is formed by a predetermined specification. After that (indicated by TW in the figure), the jig is held 60 and 61.

FIG. 6E is a view showing a state in which the glass is melted in the core half, and the glass 62 is track-controlled at a predetermined temperature while holding both core halves with a jig. It is melted in the groove 63, and the track is reinforced and the core half is sealed to form a core bar 64.

FIG. 6F is a view showing a cutting method for using the core bar as a magnetic head chip. The angle defined in the system mounted with the magnetic gap line 65 as a reference (in the figure). (AZ)) and a cutting width 66, 67, 68, 69, which is a magnetic head chip of a predetermined size, is cut on the basis of the track to obtain a magnetic head chip 70 shown in FIG.

[0016]

However, the conventional MI
In the case of a G (Metal in Gap) head, when considering a magnetic head in which the track width of a recording pattern tends to be narrow due to a demand for high density of a magnetic recording technology, a track edge is used when sputtering a soft magnetic alloy thin film. The resulting curved portion having a curvature has a remarkable leakage magnetic flux near the magnetic gap, resulting in an increase in the effective track width, which is an obstacle to narrowing the track.

Also, the track matching accuracy of the core half is severely restricted, and a submicron or less is required in some systems. Therefore, the magnetic head method that depends on the track matching accuracy has a limit in accuracy.

[0018] Furthermore, as one of the trends toward higher precision, lowering the cost of the head is an essential issue, and contriving to reduce costs by introducing a method with higher production efficiency and optimizing a structure that greatly contributes to the method. Is desired.

An object of the present invention is to provide a magnetic head effective for solving the above-mentioned problem and a method of manufacturing the same.

[0020]

In order to achieve the above object, a magnetic head and a manufacturing method according to the present invention provide a magnetic head and a method of manufacturing a MIG head, in which a track edge curved portion generated by sputtering of a soft magnetic alloy thin film is formed on a core bar once compressed. Since the main substrate and the soft magnetic alloy thin film are subjected to electric discharge machining at the stage to regulate the track, the curved portion of the soft magnetic alloy thin film and the track deviation do not occur, which can be expected to contribute greatly to the improvement of the track width and the chip after crimping. Since the ferrite and the glass, which are the substrates, are the main bonding surfaces, the strength of the MIG head can be provided higher than that of the conventional type in which the ferrite and the glass are pressed on a soft magnetic alloy thin film.

At the stage where the core halves to be paired with the magnetic head are once sealed to form a core bar, the main substrate, the soft magnetic alloy thin film and the magnetic gap member are simultaneously track-controlled by electric discharge machining with reference to the magnetic gap line. As a result, it is possible to form tracks with high precision without causing track deviation, and as a result, it is possible to regulate the effective tracks with high precision and to obtain a great effect in reducing recording fringing.

In the recording fringing, a curved portion of a track edge generated by sputtering a soft magnetic alloy thin film also poses a problem. However, according to the method of the present invention, a curved portion is formed after the soft magnetic alloy thin film is formed and cut. Does not occur.

Further, in the conventional magnetic head method, since the final track width is regulated through a plurality of steps, strict processing accuracy is required in each step, which causes a decrease in yield. However, in the method of the present invention, Since the track is regulated in the process of the electric discharge machining alone, the track width accuracy is dramatically improved.

[0024]

DESCRIPTION OF THE PREFERRED EMBODIMENTS (Embodiment 1) An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is an overall view showing a magnetic head according to the present invention. FIG.

FIG. 1 shows that the magnetic head of the present invention is
A magnetic gap 3 and a track width (which are formed with dimensions standardized by a magnetic recording system to be mounted on core halves 1 and 2 serving as a main substrate and made of a magnetic hard and brittle material (in this embodiment, single crystal ferrite is used). TW in the figure)
And glass 4 for sealing the core half and reinforcing the truck.
And a winding window 5 formed in at least one core half.

The vicinity of the magnetic gap where the structural features of the magnetic head are remarkable has the structure shown in the detailed view of part A. The structure is similar to that of the core halves 6 and 7 made of single crystal ferrite. Track regulating grooves 8 and 9 formed by electric discharge machining by regulating tracks (shown by TW in the figure) of a predetermined width at the joining interface, and glass for melting the track regulating grooves and reinforcing the tracks and sealing the core half. Further, at the magnetic gap junction interface, soft magnetic alloy thin films 11 and 12 (Fe-Ta nitride film alloy is used in this embodiment) to be main magnetic paths and a magnetic gap member (not shown in the figure)
The magnetic gap line is inclined at an angle standardized by the system (indicated by AZ in the figure) and cut into a predetermined chip width to form a magnetic head.

(Embodiment 2) An embodiment of the present invention will be described below with reference to the drawings.

FIGS. 2 and 3 are process diagrams of the magnetic head of the present invention, showing a method of manufacturing a magnetic head chip.

FIG. 2 (a) shows core halves 13 and 14 which are used as a main substrate in the magnetic head of the present invention and are made of a magnetic hard and brittle material (in this embodiment, a single crystal ferrite is used). The magnetic gap surfaces 15 and 16 to which the core halves are opposed and crimped in a later step are subjected to mirror finishing and to a predetermined surface roughness together with groove processing for forming a winding window 17 on at least one of the core halves. .

Next, FIG. 2B is a process diagram for forming a main magnetic path and a magnetic gap spacer in the core half, and shows the soft magnetic alloy thin films 18 and 19 (the present embodiment) to be the main magnetic path. In the example,
Fe-Ta nitride film) and a magnetic gap spacer.
Is continuously sputtered with a structure in which a soft magnetic alloy thin film is applied to the main substrate side.

Next, FIG. 2 (c) is a view showing a temporarily sealed state of the core halves. The core halves are opposed to each other on a magnetic gap surface 20, held by jigs 21 and 22, and then heat-treated at a predetermined temperature and pressed. By doing so, the core bar 23 is formed.

In the present embodiment, the sealing material is press-bonded using a material that melts at the sealing temperature at the magnetic gap member. However, the same effect can be obtained by a method in which glass is stored in a separately provided groove and pressed. It is not limited because it is obtained.

FIG. 2 (d) shows a method of controlling the track on the core bar. A predetermined size (in this embodiment, from the medium sliding surface side 24 to the apex 26 of the winding window 25) is shown. Electric discharge machining is performed on the discharge electrode core 27 (using φ0.1), a plurality of discharge holes 29 are formed at predetermined intervals with the magnetic gap line 28 as the center of the machining axis, and a recording / reproducing track (TW in FIG. Shown).

The machining depth of the discharge hole is to be machined to the winding window side more than the apex, and the shape of the hole is substantially determined by the operation method and shape of the discharge electrode core.

FIG. 3 (e) shows a state in which the glass is melted in the core bar. The glass 30 is melted at a predetermined temperature in the discharge hole for regulating the track, thereby reinforcing the track and strengthening the core bar. Perform the final pressure bonding.

FIG. 3F is a view showing a cutting method for using the core bar as a magnetic head chip, and shows an angle defined by a system mounted on the basis of the magnetic gap line 31 (in the figure). AZ) and the cutting widths 32, 33, 34, 35, 36 to be magnetic head chips of a predetermined size.
To obtain the magnetic head chip 37 shown in FIG.

As a countermeasure against chipping by cutting, the magnetic head chip has a step processing method in which the dimensions of the medium sliding surface side 38 and the chip bottom surface 39 are changed (the medium sliding surface side is cut with a grindstone of small abrasive grains. This suppresses chipping) and cuts into a magnetic head chip.

The step processing method is not essential, and step processing is not required as long as chipping can be tolerated.

Thereafter, although not shown in the drawing, a magnetic head chip is bonded to a metal base, and a magnetic head is completed through steps such as tape polishing and winding of a medium sliding surface.

In the first and second embodiments, the Fe-Ta nitride film is used as the soft magnetic alloy thin film. However, the same effect can be obtained by using the following soft magnetic alloy thin film instead. can get.

(1) The soft magnetic alloy thin film is made of Fe, Ni, Co
An alloy whose main component is (2) The soft magnetic alloy thin film is represented by CoaMb and is composition-modulated with nitrogen in the thickness direction.

Here, M is Nb, Ta, Zr, Hf, T
It is composed of at least one or more elements selected from i, Mo, and W, and a and b represent atomic ratios and satisfy the following formula.

0.80 ≦ a ≦ 0.95 0.05 ≦ b ≦ 0.20 a + b = 1.0 (3) The soft magnetic alloy thin film is represented by FeaMb and is composition-modulated with nitrogen in the thickness direction. thing.

Where M is Nb, Ta, Zr, Hf, T
It is composed of at least one or more elements selected from i, Mo, and W, and a and b represent atomic ratios and satisfy the following formula.

0.70 ≦ a ≦ 0.95 0.05 ≦ b ≦ 0.30 a + b = 1.0

[0047]

As described above, since the track regulation is processed at the core bar stage at a time, there is no accumulated error for each process, which is a problem in the conventional method, and high-precision track regulation can be easily realized.

Further, since recording fringing, which is a problem when mounted on an actual machine, can be greatly reduced, it is possible to regulate the effective track width with high precision.

Further, since complicated steps can be reduced in accuracy, it contributes to high accuracy and a great cost reduction can be achieved.

[Brief description of the drawings]

FIG. 1 is a diagram showing a magnetic head according to a first embodiment of the present invention.

FIG. 2 is a diagram illustrating a method of manufacturing a magnetic head according to a second embodiment of the present invention.

FIG. 3 is a diagram illustrating a method of manufacturing a magnetic head according to a second embodiment of the present invention.

FIG. 4 is a diagram showing a magnetic head in a conventional example of the present invention.

FIG. 5 is a diagram showing a method of manufacturing a magnetic head in a conventional example of the present invention.

FIG. 6 is a diagram showing a method of manufacturing a magnetic head in a conventional example of the present invention.

[Explanation of symbols]

 1, 2 core half 3 magnetic gap 4 glass 5 winding window 6, 7 core half 8, 9 track regulating groove 10 glass 11, 12 soft magnetic alloy thin film

Claims (8)

[Claims] 1. A pair of soft magnetic alloy thin films between a pair of core halves made of a magnetic hard and brittle material, a pair of non-magnetic thin films between the pair of soft magnetic alloy thin films, and a core half sealed. A magnetic head having a medium sliding surface made of glass having a predetermined width and a recording / reproducing track having a predetermined width and a magnetic gap. A hole having a predetermined depth at an interval determined by the sum of a predetermined track width dimension and a track regulating groove width dimension with reference to a magnetic gap line of a pair of core halves in which a magnetic gap surface of a body is opposed and primary sealed. A magnetic head is characterized in that the main processing of the hole processing is performed by discharge energy, and the hole has a track regulating groove having a structure in which the electrode shape is almost transferred. 2. A step of forming a winding window for winding a coil in a magnetic head in one of a pair of core halves made of a magnetic hard and brittle material; A step of mirror-polishing the gap surface to a predetermined surface roughness, a step of sputtering a soft magnetic alloy thin film serving as a main magnetic path on the pair of core halves, and a step of forming a magnetic gap member on the pair of core halves. A step of sputtering a magnetic thin film, a step of bringing the pair of core halves to face each other on a magnetic gap surface and pressing the core halves at a predetermined temperature to form a core bar, and a magnetic gap in the direction of the winding window from the medium sliding surface side of the core bar. A step of forming a plurality of holes by electric discharge machining at an interval leaving a predetermined track width based on the line, a step of sputtering a film for preventing a reaction between the soft magnetic alloy thin film and the glass on the core bar, and a step of discharging the core bar A method of filling a hole with glass at a predetermined temperature; and cutting the core bar into a magnetic head of a predetermined size. 3. A soft magnetic alloy thin film comprising Fe, Co, Ni
2. An alloy mainly composed of:
The magnetic head as described. 4. The soft magnetic alloy thin film is represented by CoaMb,
2. The magnetic head according to claim 1, wherein the composition is modulated with nitrogen in the thickness direction. Here, M is Nb, Ta, Zr, Hf, Ti, M
It is composed of one or more elements of o and W, and a and b represent an atomic ratio and satisfy the following expression. 0.70 ≦ a ≦ 0.95 0.05 ≦ b ≦ 0.30 a + b = 1.0 5. The soft magnetic alloy thin film is represented by FeaMb,
2. The magnetic head according to claim 1, wherein the composition is modulated with nitrogen in the thickness direction. Here, M is Nb, Ta, Zr, Hf, Ti, M
It is composed of one or more elements of o and W, and a and b represent an atomic ratio and satisfy the following expression. 0.70 ≦ a ≦ 0.95 0.05 ≦ b ≦ 0.30 a + b = 1.0 6. A soft magnetic alloy thin film comprising Fe, Co, Ni
3. An alloy mainly composed of:
The manufacturing method of the magnetic head described. 7. The soft magnetic alloy thin film is represented by CoaMb,
3. The method of manufacturing a magnetic head according to claim 2, wherein the composition is modulated with nitrogen in a thickness direction. Where M is Nb, Ta, Zr, H
f, consisting of one or more elements of Ti, Mo, W, a, b
Represents the atomic ratio and satisfies the following equation. 0.70 ≦ a ≦ 0.95 0.05 ≦ b ≦ 0.30 a + b = 1.0 8. The soft magnetic alloy thin film is represented by FearMb,
3. The method of manufacturing a magnetic head according to claim 2, wherein the composition is modulated with nitrogen in a thickness direction. Where M is Nb, Ta, Zr, H
f, consisting of one or more elements of Ti, Mo, W, a, b
Represents the atomic ratio and satisfies the following equation. 0.70 ≦ a ≦ 0.95 0.05 ≦ b ≦ 0.30 a + b = 1.0