JPH0814886B2 - Manufacturing method of thin film magnetic head - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention forms a magnetic circuit portion composed of a lower magnetic film, a coil conductor, an upper magnetic film, an insulating film and the like by a semiconductor manufacturing process such as a photolithography technique. And a method for forming the lower magnetic film.

[Outline of Invention]

According to the present invention, when manufacturing a thin film magnetic head, an insulating film is formed on the entire surface of a substrate in advance, a groove having a width substantially equal to the track width is formed in the insulating film, and a lower magnetic film is formed in the groove. By forming it, a step is formed in the vicinity of the track, and a coil conductor and an upper magnetic film are formed on this, or a lower magnetic film is formed on the entire surface of the substrate in advance and half etching is performed on this lower magnetic film. By forming a convex part having a width approximately equal to the track width to form a step in the vicinity of the track and forming a coil conductor and an upper magnetic film on this, crosstalk from adjacent tracks can be reduced, and It is intended to manufacture a product having excellent patterning accuracy and good electromagnetic conversion characteristics.

[Conventional technology]

In the field of magnetic recording, magnetic recording media are becoming higher in coercive force along with higher density recording, and the recording / reproducing wavelength is becoming shorter. Therefore, in the magnetic head as well, a core material having a high saturation magnetic flux density is used, and a narrow gap is promoted to cope with the above high density recording.

Under such circumstances, it is well known that a thin film magnetic head formed by a thin film forming technique has been developed and put into practical use.

In general, a thin film magnetic head is excellent in mass productivity because magnetic thin films and coil conductors forming a magnetic circuit section are formed by a vacuum thin film forming technique typified by sputtering. It has many advantages such as easy miniaturization and high-resolution recording, and is attracting attention as a magnetic head compatible with high-density recording.

Conventionally, the above-mentioned thin film magnetic head has a lower magnetic film formed on a flat substrate made of, for example, Mn-Zn ferrite, and the coil conductor and the upper magnetic film are photolithographically formed on the lower magnetic film via an insulating film. It is manufactured by sequentially laminating using a technique, and a closed magnetic path is formed by the cooperation of the lower magnetic film and the upper magnetic film, and recording / reproducing is performed.

[Problems to be solved by the invention]

In the thin film magnetic head, the track width is regulated by patterning the upper magnetic film or the lower magnetic film, but various improvements remain.

That is, when the above-mentioned track width regulation is performed by the upper magnetic film, the upper magnetic film is divided so as to match the track width, whereas the lower magnetic film is formed by a common series of film attachments. In the multi-channel thin film magnetic head that is formed, the lower magnetic film is common to each channel, and thus crosstalk during off-track is a problem. This is due to reproduction of a signal from the lower magnetic film other than the track forming portion (so-called pseudo signal), which causes deterioration of recording / reproducing characteristics.

Also, when performing signal correction through the error correction circuit,
It is necessary to secure a C / N value of 41 to 44 dB or more, but with a head with a common lower magnetic film as described above, it is not possible to obtain a sufficient C / N value due to the above crosstalk, and it should be used as a digital reaction head. I can't.

On the other hand, there is also a method of controlling the track width by the lower magnetic film, but in this case, there is a drawback that the step difference between the tracks after patterning the lower magnetic film becomes large. That is, when patterning the coil conductor and the upper magnetic film, the coating thickness of the resist varies, and the patterning cannot be performed accurately. In some cases,
The coil conductor may be short-circuited or the resist that has entered between the tracks may remain. Therefore, there is a problem that good electromagnetic conversion characteristics cannot be obtained.

Therefore, the present invention has been proposed in view of the above circumstances, and can reduce crosstalk from adjacent tracks,
It is an object of the present invention to provide a method for manufacturing a thin film magnetic head having excellent patterning accuracy of a coil conductor and good electromagnetic conversion characteristics.

[Means for solving problems]

In order to achieve the above-mentioned object, the present invention provides a thin film magnetic head for forming a plurality of channels of a thin film magnetic head in which a lower magnetic film, a coil conductor, and an upper magnetic film are sequentially laminated on a substrate through an insulating film. In the method, first, an insulating film is formed on the entire surface of the substrate, and a groove having a width substantially equal to the track width with respect to the insulating film and a groove continuous with these grooves and continuous in the track width direction are formed. A lower magnetic film is formed on the entire surface, and the lower magnetic film in the portions other than the groove is removed to form a step in the track width direction near the track for each channel, and the other portions are made continuous films. The coil conductor and the upper magnetic film are formed thereon by a photolithography technique. Alternatively, first, the lower magnetic film is formed on the entire surface of the substrate, and the lower magnetic film is formed. Half-etching is performed on the magnetic film to form a convex portion having a width substantially equal to the track width to form a step in the track width direction near the track for each channel, and a flat film that is continuous in other portions. The coil conductor and the upper magnetic film are formed on this by a photolithography technique.

[Action]

A groove is formed in the insulating film on the substrate, and a lower magnetic film is further formed so that the step in the vicinity of the track of the lower magnetic film is made smaller than the film thickness of the lower magnetic film. Since the conductor and the upper magnetic film are formed, the resist is applied with a substantially uniform thickness when patterning the coil conductor and the like. Therefore, patterning that is faithful to the resist pattern can be performed.

On the other hand, the lower magnetic film on the substrate is half-etched so that the step difference in the track vicinity of the lower magnetic film is smaller than the film thickness of the lower magnetic film, and the coil conductor and the upper magnetic film are formed thereon. Since it is formed, the resist is applied with a substantially uniform thickness when patterning the coil conductor and the like. Therefore, patterning that is faithful to the resist pattern can be performed.

〔Example〕

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In this embodiment, a two-channel thin film magnetic head will be described as an example, but it goes without saying that the present invention is not limited to this embodiment.

First, regarding the first invention, FIG.
Description will be given with reference to FIGS. 6 (B) to 6 (A) and 6 (B).

In order to manufacture the thin film magnetic head according to the first aspect of the present invention, first, as shown in FIGS. 1 (A) and 1 (B), the first step is performed so as to cover one plane of the substrate (11). Insulating film (1
2) is deposited.

As the substrate (11), Mn-Zn ferrite or Ni-Zn
Ferromagnetic oxide materials such as series ferrite and non-magnetic materials such as barium titanate, calcium titanate, and MnO-NiO ceramics are used.

Further, the film thickness a of the first insulating film (12) may be appropriately selected in consideration of the film thickness of the lower magnetic film described later, and in this embodiment, it is formed to 3 μm. If this film thickness a is extremely smaller than the film thickness of the lower magnetic film or, on the contrary, too large, the step difference between the tracks cannot be alleviated and the initial purpose cannot be achieved. The material of this insulating film (12) is SiO ₂ , A
A non-magnetic material such as l ₂ O ₃ or Ta ₂ O ₅ is used, and as the film forming method, a vacuum thin film forming technique typified by sputtering or the like is adopted.

Next, as shown in FIGS. 2 (A) and 2 (B),
Plasma etching is performed on the first insulating film (12) to form a groove (13) having a width substantially equal to a predetermined track width.

The groove (13) includes a groove (13a) on the front gap side and a groove (13b) on the back gap side. In the groove (13a) on the front gap side, the width Tw in the width direction X of the contact surface of the magnetic recording medium is substantially equal to the predetermined track width (equivalent or slightly larger), and the direction Y of the contact surface of the magnetic recording medium is larger. Is formed so that the width Dp thereof is at least larger than a predetermined depth length. Further, the groove (13b) on the back gap side is continuously formed in each channel.

Then, as shown in FIGS. 3 (A) and 3 (B), a ferromagnetic amorphous alloy, a so-called amorphous alloy, Fe-- is formed on the entire surface of the first insulating film (12) including the groove (13). After depositing a ferromagnetic metal material such as Al-Si alloy, Fe-Ni alloy, etc. using the vacuum thin film forming technique, the ferromagnetic metal material other than the groove (13) is subjected to ion etching or the like. Then, the lower magnetic film (14) is formed.

Therefore, in the groove (13), the lower magnetic film (1
4) is filled. In the vicinity of the tracks, the lower magnetic film (14) is divided for each track, and the first insulating film (12) remains between the tracks. Therefore, in the vicinity of the front gap, the step due to the lower magnetic film (14) is relaxed by the first insulating film (12). It is more preferable that the upper surface (11a) is substantially flat if the film thickness a of the first insulating film (12) is equal to the film thickness b of the lower magnetic film (14).

Here, if the film thickness b of the lower magnetic film (14) is too small, the lower magnetic film (14) is likely to be magnetically saturated, and conversely if the film thickness b of the lower magnetic film (14) is too large. A lot of time is required for attachment and patterning, and there is a problem in productivity. Under such circumstances, the thickness b of the lower magnetic film (14)
Is preferably about 5 to 10 μm.

Subsequently, as shown in FIGS. 4A and 4B, a coil conductor (15) and a gap spacer (16) are formed by using a semiconductor manufacturing process such as a photolithography technique.

That is, the coil conductor (15) is formed by depositing a conductive metal material such as Cu or Al on the entire surface of the upper surface (11a) of the substrate (11) by sputtering or the like through an insulating film (not shown), and then performing a predetermined process. It is formed by patterning into a shape (spiral two-turn winding structure in this embodiment). Here, the winding structure of the coil conductor (15) is not limited to the spiral winding structure described above, and may be any winding structure such as spiral multi-layer type, multi-layer helical type, or zigzag type.

As described above, the coil conductor (15) is formed on the upper surface (11a) in which the step due to the lower magnetic film (14) is relaxed by the first insulating film (12), and thus the pattern of the coil conductor (15) is formed. At the time of etching, the coating thickness of the resist becomes uniform, and patterning can be performed faithfully to the mask pattern. Therefore, even if the exposure conditions and the development conditions are loosely set, there is no short circuit between the coil conductors (15) and no resist remains, and the patterning accuracy is greatly improved.

Further, as the gap spacer (16), SiO ₂ , A
l ₂ O ₃ , Ta ₂ O _{5 and} other non-magnetic materials, or the above non-magnetic materials
A composite material in which non-magnetic metals such as Cr and Ti are alternately laminated can be used, and films are formed by the above vacuum thin film forming technique.

Then, as shown in FIGS. 5 (A) and 5 (B), after forming an insulating film (not shown) on the upper surface (11a) including the coil conductor (15), a heat-resistant resin or a heat-resistant resin is formed. A resin layer (18) made of a conductive resist is formed, and the resin layer (18) is etched to have a predetermined track width to form an upper magnetic film forming portion (19). Examples of the heat resistant resin include PIQ (trade name) manufactured by Hitachi Chemical Co., Ltd., Pyralin (trade name) manufactured by DuPont, and S
P series, etc. can be used polyimide resin excellent in heat resistance, and as the heat resistant resist, OMR-83 series manufactured by Tokyo Ohka Co., Ltd., JSR series manufactured by Japan Synthetic Rubber Co., Ltd., etc. are excellent in heat resistance. A rubber type negative resist can be used.

Next, as shown in FIGS. 6 (A) and 6 (B),
The ferromagnetic metal material is deposited on the resin layer (18) including the upper magnetic film forming portion (19) by vacuum thin film forming technique such as sputtering for 5 to 10 μm, and then the ferromagnetic material on the resin layer (28) is formed. The metal material is removed to form the upper magnetic film (17). As a result, a thin film magnetic head whose track width is regulated by the upper magnetic film (17) is completed. After removing the ferromagnetic metal material on the resin layer (28), the resin layer (18) is removed if necessary.

Also in this case, the step difference between the tracks is the first insulating film (1
Since it is relaxed by 2), the internal stress of the upper magnetic film (17) is relaxed, and the thin film magnetic head with excellent magnetic characteristics is obtained.

Further, although not shown, usually, after the substrate (11) is cut at a predetermined position, a magnetic field composed of the lower magnetic film (14), the coil conductor (15), the upper magnetic film (17), etc. In order to protect the circuit part and ensure contact with the magnetic recording medium, a protective film is formed on the upper magnetic film (17), and an adhesive such as glass is used on the protective film to protect the circuit from ceramics. The protective plate is fusion bonded. Then, in order to ensure sliding contact with the magnetic recording medium and to obtain a predetermined depth length, the magnetic recording medium contact surface is subjected to cylindrical polishing.

In the thin-film magnetic head manufactured as described above, the lower magnetic film (14) and the upper magnetic film (17) are separated for each track, so the pseudo signal due to crosstalk from the adjacent tracks is significantly reduced. However, it becomes excellent in electromagnetic conversion characteristics.

Next, a second invention of the present invention will be described with reference to FIGS. 7 (A) and 7 (B) to 10 (A) and 10 (B). In the following description, since the same material can be used for the same member as the first invention, the description thereof will be omitted.

First, as shown in FIGS. 7 (A) and 7 (B),
The lower magnetic film (22) so as to cover one plane of the substrate (21).
Is formed by a vacuum thin film forming technique. This lower magnetic film (22)
The film thickness c is preferably about 5 to 10 μm as in the first invention.

Next, as shown in FIGS. 8 (A) and 8 (B),
The lower magnetic film (22) is half-etched to form a protrusion (23) and a recess (24) having a width substantially equal to the track width. The above half etching is performed on the lower magnetic film (22).
Until the film thickness b of is about 1/2. However, the lower magnetic film (22) of the portion (21a) corresponding to the electrode forming portion of the coil conductor described later is completely removed by ion etching.

Here, the convex portion (23) includes a back gap side convex portion (23a) and a convex portion (23b) of the front gap side convex portion (23a), and the front gap side convex portion (23a) is a magnetic recording medium pair. The width Tw of the contact surface in the width direction X is substantially equal to the predetermined track width, and the width Dp of the contact surface in the contact surface direction Y is larger than at least the predetermined depth length. Further, the back gap side convex portion (23b) is formed continuously in each channel to form a flat surface.

Thus, the lower magnetic film (22) is composed of the convex portion (23) and the concave portion (24), the convex portion (23) corresponds to the track forming portion, and the concave portion (24) corresponds to the guard band portion. Equivalent to.
Therefore, in the vicinity of the front gap, the step difference of the convex portion (23) forming the track is relaxed by the concave portion (24).

Then, as shown in FIGS. 9 (A) and 9 (B), the coil conductor (25) and the gap spacer (26) are formed through an insulating film (not shown) as in the first invention. It is formed by the method of.

As described above, the coil conductor (25) has a substantially flat substrate (2
1) Since it is formed on the resist, the resist can be applied to have a substantially uniform thickness during this patterning, so that patterning faithful to the resist pattern is possible. Therefore,
This patterning accuracy is greatly improved by eliminating short circuit of the coil conductor (25) and residual resist.

Then, as shown in FIGS. 10 (A) and 10 (B), the lower magnetic film of the recess (24) is removed by ion etching, and the lower magnetic film (2
2) is formed so that each track is independent.

Thereafter, the upper magnetic film is formed and the thin film magnetic head is completed in the same manner as in the first invention.

In this way, the lower magnetic film (22) is half-etched to form the protrusions (23) having a width substantially equal to the track width, thereby improving the etching accuracy of the coil conductor (25). In addition, the lower magnetic film (22) between the tracks is
Since the etching is performed separately, the etching resistance of the resist is improved, and the patterning accuracy of the lower magnetic film (22) is also improved.

Further, in the thin film magnetic head manufactured as described above, since the lower magnetic film (22) and the upper magnetic film (29) are divided for each track on the contact surface of the magnetic recording medium, a cross from adjacent tracks is formed. The talk is improved and the electromagnetic conversion characteristics are excellent.

〔The invention's effect〕

As is apparent from the above description, the step near the track due to the division of the lower magnetic film into each track is subjected to half etching on the lower magnetic film by the insulating film in the first invention and in the second invention. The patterning accuracy of the coil conductor and the upper magnetic film is significantly improved because the coil conductor and the upper magnetic film are formed thereon.
Therefore, a thin film magnetic head excellent in electromagnetic conversion characteristics and reliability can be obtained.

Further, in the thin film magnetic head manufactured according to the present invention, since the lower magnetic film and the upper magnetic film are independently formed for each track on the contact surface of the magnetic recording medium, crosstalk from adjacent tracks can be reduced and recording / reproducing characteristics can be improved. It will be excellent. Therefore, the present invention is suitable for manufacturing a thin-film magnetic head for digital recording / reproduction with a strict regulation on C / N value.

[Brief description of drawings]

1 to 6 show the first invention according to the steps thereof. FIG. 1 (A) is a perspective view showing a step of forming a first insulating film, and FIG. 1 (B) is shown in FIG. 2A is a perspective view showing the patterning process of the first insulating film, FIG. 2B is a sectional view taken along line BB of FIG. 2A, and FIG. A) is a perspective view showing a lower magnetic film forming step, FIG. 3B is a sectional view taken along line CC of FIG. 3A, and FIG. 4A is a perspective view showing a coil conductor and gap spacer forming step. , Fig. 4 (B) is Fig. 4 (A) DD
5A is a perspective view showing a resin layer forming step, FIG. 5B is a sectional view taken along line EE of FIG. 5A, and FIG. 6A is an upper magnetic film. FIG. 6 (B) is a perspective view showing the forming step, and FIG. 6 (B) is a sectional view taken along line FF in FIG. 6 (A). 7 to 10 show the second invention according to the steps thereof. FIG. 7 (A) is a perspective view showing the lower magnetic film forming step, and FIG. 7 (B) is FIG. 7 (A). Sectional view taken along the line GG, FIG. 8A is a perspective view showing the half-etching step, FIG. 8B is a sectional view taken along the line HH of FIG. 8A, and FIG. 9A is a coil conductor and FIG. 9 (B) is a perspective view showing the gap spacer forming step, and FIG. 9 (A) II.
10A is a perspective view showing the step of removing the lower magnetic film between tracks, and FIG. 10B is a sectional view taken along line JJ of FIG. 10A. 11,21 …… Substrate 12 …… First insulating film 13 …… Groove 14,22 …… Lower magnetic film 15,25 …… Coil conductor 17,29 …… Upper magnetic film 23 …… Protrusions

Claims (2)

[Claims] 1. A method of manufacturing a thin film magnetic head in which a plurality of channels are formed in a thin film magnetic head in which a lower magnetic film, a coil conductor and an upper magnetic film are sequentially laminated on a substrate with an insulating film interposed therebetween. After forming an insulating film on the entire surface of the above, and forming a groove having a width substantially equal to the track width with respect to the insulating film and a groove continuous with these grooves in the track width direction,
A lower magnetic film is formed on the entire surface, and the lower magnetic film in the portions other than the groove is removed to form a step in the track width direction near the track for each channel, and the other portions are made continuous films. A method of manufacturing a thin film magnetic head, characterized in that a coil conductor and an upper magnetic film are formed thereon by a photolithography technique. 2. A method of manufacturing a thin film magnetic head in which a lower magnetic film, a coil conductor, and an upper magnetic film are sequentially laminated on a substrate via an insulating film to form a plurality of channels in a thin film magnetic head. Lower magnetic film is formed on the entire surface of the above, and half etching is applied to the lower magnetic film to form a convex portion having a width substantially equal to the track width, and a step is formed in the track width direction in the track vicinity for each channel. A method for manufacturing a thin film magnetic head, characterized in that a flat film which is continuous with the other portions is formed, and a coil conductor and an upper magnetic film are formed on the flat film by a photolithography technique.