JPH03104009A - Thin film magnetic head - Google Patents

Abstract

PURPOSE:To prevent a thin film magnetic head from being destroyed by conducting a coil conductor and a slider substrate. CONSTITUTION:Is charged with static electricity plastic case housing the thin film magnetic head static electricity by friction at the time of conveyance. When the lead wire of the head gets contact with this case, a high voltage is applied to a coil conductor 15. Since an insulated protecting film 12 is interposed between the conductor 15 and an upper magnetic layer 14, an inverse electric charge is generated in the layer 14. A slider substrate 11 equipped with sufficiently larger conductivity than that of the layer 14 apparently comes to a ground and it can be considered that the inverse electric charge is leaked to the substrate 11. Thus, by conducting the substrate 11 and the conductor 15, the voltage acts on the whole substrate 11 and the layer 14 is prevented from being charged with the inverse electric charge. Then, the conductor 15 and the substrate 11 are set to the same potential and the material of the thin film magnetic head can be prevented from being destoryed.

Description

[Detailed Description of the Invention] [Summary] An insulating protective film is formed on a conductive slider substrate, one end is connected to the insulating protective film, and a magnetic gap is formed at the other end. Regarding a thin film magnetic head that has a lower magnetic layer and an upper magnetic layer and a coil conductor between the lower magnetic layer and the upper magnetic layer, this prevents the destruction of the upper magnetic layer of the thin film magnetic head and the material of the slider substrate during the transportation stage, etc. The present invention aims to provide a thin film magnetic head that can be used in a thin film magnetic head, and is constructed so that the coil conductor and the slider substrate are electrically connected to each other.

[Industrial Application Field] An insulating protective film is formed on a conductive slider substrate, and a lower magnetic layer is connected to the insulating protective film at one end and a magnetic gap is formed at the other end. The present invention relates to a thin film magnetic head having a coil conductor between the lower magnetic layer and the upper magnetic layer.

In recent years, there has been a demand for increased storage capacity in magnetic disk devices. One way to increase storage capacity is to increase linear recording density. In order to improve the linear recording density, a high coercive force medium and a thin film magnetic head, which is a type of magnetic head with a high saturation magnetic flux density that can sufficiently magnetize the medium, are required.

[Prior Art] FIG. 5 is a plan view showing an example of a thin film magnetic head, and FIG. 6 is a sectional view taken along line AA in FIG.

First, the structure of a thin film magnetic head made by microphotolithography will be explained using these figures. In the figure, 1 is a slider substrate. This slider board 1 is
Artic (Af) is generally a non-magnetic and conductive material.
f 2 03 T i C) is used. 2 is an insulating protective film formed on the slider substrate 1, 3 and 4 are provided on the insulating protective film 2, one end (base end) S is connected, and the other end (tip) is connected to a magnetic gap. These are the lower magnetic layer and the upper magnetic layer of Vermalloy in which G is formed. Lower magnetic layer 3
A nonmagnetic gap layer 5 is formed thereon to fill the magnetic gap G. An insulating protective film 6 is formed on this gap layer 5, and a spirally patterned coil conductor 7 is provided on this insulating protective film 6. The remaining space between the lower magnetic layer 3 and the upper magnetic layer 4 is filled with an insulating protective film 8. 9 is a magnetic recording medium, and this magnetic recording medium 9 moves in the direction of the arrow in FIG.

Then, recording/reproduction is performed by the magnetic field generated in the gap G.

[Problems to be Solved by the Invention] However, in the conventional thin film magnetic head having the above structure, the slider substrate 1 and the coil conductor 7 are insulated using the insulating protective film layers 2 and 6. .

In addition, such thin-film magnetic heads are not assembled into magnetic disk drives immediately after manufacture, with lead wires with uncoated ends attached, and are not assembled into magnetic disk drives until they are used.
It is stored in a plastic case, etc., and is transported and stored in a warehouse or the like.

In such a conventional thin film magnetic head, when taken out from the plastic case, material destruction occurs at the tip of the upper magnetic layer 4 and the slider substrate 1 closest to this tip, which is thought to be due to leakage. Something happened.

In a thin-film magnetic head with such damage, the properties of the upper layer 4 made of vermalloy deteriorate, and head crashes occur due to the action of fine particles generated from the uneven surface and charred portions on the slider substrate l side. I had something to do.

The present invention has been made in view of the above problems, and an object thereof is to provide a thin film magnetic head that can prevent the upper magnetic layer and the slider substrate from being destroyed.

[Means for Solving the Problems] Fig. 1 is a diagram showing the principle of the present invention, in which (a) is a partially broken plan view, (b) is a BB sectional view in (a), and (C) is a partially broken plan view.
is a C-C diagram in (b). In the figure, 1
1 is a nonmagnetic and conductive slider substrate; 12 is an insulating protective film formed on the slider substrate 11; 13.14
are a lower magnetic layer and an upper magnetic layer which are connected at one end to the insulating protective film 12 and are provided so that a magnetic gap G is formed at the other end. 15 are these lower magnetic layers 13
and a coil conductor provided between the upper magnetic layer 14.

As shown in (C), the coil conductor 15 and the slider substrate 11 are electrically connected.

[Function] In the thin film magnetic head shown in FIG. 1, since the coil conductor 15 and the slider substrate 11 are electrically connected, the coil conductor 1
5 and the slider substrate 11 are always at the same potential.

That is, as a result of the applicant's investigation into the cause of destruction of the material of the tip of the upper magnetic layer 14 and the material of the slider substrate 11 near the tip, the following was found i11.

In other words, the plastic case in which the thin-film magnetic head is housed is charged with static electricity due to friction due to vibration during transportation.

When a lead wire of a thin-film magnetic head touches a portion charged with static electricity, a high voltage is applied to the coil conductor due to the static electricity.

At this time, since an insulating protective film is interposed between the coil conductor 15 and the upper magnetic layer 14, when a high voltage is applied to the coil conductor 15, a reverse charge is generated in the upper magnetic layer 4, similar to the action of a capacitor. It is thought that then.

The reverse charge on the upper magnetic layer 14 is caused by the slider substrate 11 having a sufficiently large conductivity compared to the upper magnetic layer 14.
It is considered that the ground apparently became a ground and leaked to the slider substrate 11.

Therefore, in the present invention, the slider substrate 11 and the coil conductor 15 are electrically connected so that a voltage acts on the entire slider substrate 11 and the upper magnetic layer 14 is not charged with a reverse charge.

[Example] Next, an example of the present invention will be described using the drawings. Second
The figure is a plan view showing a thin film magnetic head according to an embodiment of the present invention.
3 is a sectional view taken along the line DD in FIG. 2, and FIG. 4 is a sectional view taken along the line EE in FIG.

In these figures, 21 is a slider substrate. The slider substrate 21 is generally made of AlTiC (AN 20s TiC), which is a non-magnetic and conductive material. 22 is an insulating protective film formed on the slider substrate 21, 23.2
4 is provided on the insulation protection film 22, and one end (base end) S
are connected to each other, and a permalloy lower magnetic layer and an upper magnetic layer are formed with a magnetic gap G at the other end (tip end). A nonmagnetic gap layer 25 is formed on the lower magnetic layer 23 so as to fill the magnetic gap G. An insulating protective film 26 is formed on this gap layer 25, and a spirally patterned coil conductor 27 is provided on this insulating protective film 26. And the lower magnetic layer 23
The remaining space of the upper magnetic layer 24 is filled with an insulating protective film 28. 29 is a magnetic recording medium, and this magnetic recording medium 29 moves in the direction of the arrow in FIG.

In this embodiment, the slider substrate 21 has a length of 4 mm,
Although the width is 3.2 mm and the height is 0.85 mm, the upper magnetic layer 2
4 has a width and length of 0.15mm and a thickness of 0.005mm
The slider substrate 21 has a volume of the upper magnetic layer 24.
The volume of is large enough.

Furthermore, as shown in FIG. 4, one terminal portion of the coil conductor 27 is in contact with the slider substrate 21 to establish electrical continuity. Further, the slider substrate 21 is attached to the swing type head arm of the magnetic disk device in an insulated state from the head arm by using an insulating adhesive or the like. This prevents the current that should flow through the coil conductor during recording/reproduction from flowing into a grounded member such as the head arm via the slider substrate 21.

Then, by the magnetic field generated in the gap G, recording/reproduction is performed on the two recording media.

According to the above configuration, the coil conductor 27 and the slider board 21
The potentials are always equal. Therefore, it is possible to prevent the materials of the upper magnetic layer 24 and slider substrate 21 of the thin film magnetic head from being destroyed during transportation or the like.

[Effects of the Invention] As explained above, according to the present invention, since the coil conductor and the slider substrate are configured to be electrically connected, the potentials of the coil conductor and the slider substrate are equalized, and the material of the thin film magnetic head is A thin film magnetic head that can prevent damage can be realized.

[Brief explanation of drawings]

FIG. 1 is a diagram of the principle of the present invention, FIG. 2 is a plan view showing a thin film magnetic head according to an embodiment of the present invention, FIG. 3 is a sectional view taken along line DD in FIG. 2, and FIG. 5 is a plan view showing an example of a thin film magnetic head, and FIG. 6 is a sectional view taken along A-A in FIG. 1 to 4, II-; 21 is a slider substrate; 12, 13, 14, 15, and 22 are insulating protective films; 23 is a lower magnetic layer; 24 is an upper magnetic layer; and 25 is a coil conductor.

Claims (1)

[Claims] An insulating protective film (12) on a conductive slider substrate (11).
A lower magnetic layer (13) and an upper magnetic layer (14) are formed such that one end is connected to the insulating protective film (12) and a magnetic gap (G) is formed at the other end. In a thin film magnetic head in which a coil conductor (15) is provided between the lower magnetic layer (13) and the upper magnetic layer (14), the coil conductor (15) and the slider substrate (11) are electrically connected. A thin film magnetic head featuring: