JPH04114307A - Thin film magnetic head - Google Patents

Abstract

PURPOSE:To enable the electromagnetic shield and electrostatic shield of a head element and to reduce noise from an external space by grounding a good conductive film while covering the head element. CONSTITUTION:At the upper part of a conductor layer 12, a bonding pad 14 is arranged by the side of a coil conductor layer 9 and electrically connected to the said conductor layer 12. The upper end of the pad 14 is passed through a protecting layer 5 and exposed to the outside and there, a wire 16 is connected through a terminal 15. On the upper face of the protecting film 5, a satisfactory conductor film 17 composed of gold or the like is laminated excepting for a part A near the exposed part of the pad 14 and a linear part B reaching from the part A to the side end part of this thin film magnetic head. The good conductor film 17 is grounded and connected through a ground terminal 18 by a wire 19.

Description

[Detailed description of the invention] "Industrial application field" The present invention relates to a thin film magnetic head.

``Prior Art'' A thin film magnetic head has upper and lower magnetic layers on a substrate with an appropriate gap layer between them, a coil conductor layer between the upper and lower magnetic layers, and a coil conductor layer between the upper and lower magnetic layers. It has a structure covered with a protective film, and when the magnetic medium is moved along the nodule to this thin film magnetic field, the magnetic flux flows from the magnetic medium to the lower magnetic layer, passes through the contact area, reaches the upper magnetic layer, and becomes magnetic again. The flow returns to the medium, and the change at this time is extracted as a change in the induced voltage that occurs in the coil conductor layer.
This reproduces the information recorded on the magnetic medium.

This type of thin film magnetic head has the disadvantage that it is easily influenced by external noise because the signal voltage to be reproduced is very small. To address these shortcomings, Japanese Patent Application Laid-open No. 2-6
Japanese Patent No. 1812 proposes a method in which a 7-fold plate layer is provided within a protective film to cover the coil conductor [i].

"Problems to be Solved by the Invention" However, the technology proposed in the above publication has a structure in which the shield plate layer is placed inside the protective film, and the protective film is usually manufactured by sputtering alumina. Therefore, when manufacturing a protective film, it is necessary to interrupt the sputtering process midway through, interpose a shield plate layer in between, and perform the sputtering process again, which complicates the process for manufacturing the protective film. There were drawbacks.

The present invention was made to solve the above-mentioned problems, and its purpose is not only to reduce external noise, but also to provide a thin film magnetism that can be easily manufactured. It is.

"Means for Solving the Problems" □ In order to achieve the above object, the present invention provides a thin film magnetic head in which a head element and a protective film covering the head element are provided on a substrate. A configuration was adopted in which a good conductor film was formed and this good conductor film was connected to earth.

"Function" Since the good conductor film covers the head element and is grounded, the head element can be electromagnetically and electrostatically shielded from the outside, and noise from the outside space can be reduced.

Further, since the good conductor is disposed on the upper surface of the protective film, it can be manufactured separately from the protective film, and can be easily manufactured, for example, by plating, scorching, or vine processing when manufacturing a honting bat.

"Example" Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

Figure 1 is a perspective view of a thin film magnetic head, and Figure 2 is
It is a sectional view taken along the line -■. Reference numeral in the figure] indicates a substrate made of ceramic or resin, and an insulating layer 2 is laminated on top of the substrate. On the top of the insulating layer 2.

The lead element 3 and the lead terminal 4 are provided partially overlapping each other, and are covered with a protective film 5 made of alumina or the like.

The head element 3 includes a lower magnetic layer 6 on top of the insulating layer 2.
, a cab layer 7, a coil conductor layer 9 covered with a fill conductor interlayer insulating layer 8, an upper magnetic layer 10, and an insulating layer 11, which are laminated in this order. On the other hand, the lead terminal 4 has a conductor layer 12 laminated on top of the insulating layer 2, and a half of the coil conductor layer 9 covered with the coil conductor interlayer insulation layer 8 and an insulating layer 11 are laminated in order on top of the conductor layer 12. , and the conductor layer 12 is configured to be electrically connected to the coil conductor layer 9. Further, on the upper part of the conductor layer 12, a honting pad 14 is arranged on the side of the coil conductor layer 9 and is electrically connected to the conductor layer 12. The upper end of the bonding pad 14 penetrates the protective layer 5 and is exposed to the outside, and a wire 16 is connected thereto via a terminal 15.

A good conductor film 17 made of gold or the like is formed on the upper surface of the protective film 5 in the vicinity A of the exposed portion of the honting pad 14 and from there to the side edge of the thin film magnetic head (see FIG. 1).
They are laminated except for the straight line portion B that reaches up to (a) and (b)). The good conductor film 17 is made by laminating materials with excellent conductivity, such as gold, by means of sputtering, plating, or the like. The good conductor film 17 is connected to the ground terminal (
It is grounded by a wire 19 via a center tap (18).

Here, a good conductor film 17 is laminated on the upper surface of the protective film 5.
To explain the manufacturing method, in the Ueno manufacturing process, a protective film 5 for protecting the head element 3 is formed by sputtering, and the surface of the protective film 5 is smoothed by lapping. Then, on the upper surface of the protective film 5 thus formed, a suitable conductive material is laminated to a thickness of 5 .mu.m to 6 .mu.m by sputtering or plating.

After that, make sure that only the ground terminal is connected and other terminals 15 are not electrically connected.

The vicinity A of the head 14 and the straight line portion B extending therefrom to the side end face of the thin film magnetic head are removed by means such as etching.

By the above method, a good conductor film 17 having a predetermined thickness can be formed on the upper surface of the protective film 5.

According to the thin film magnetic head having the above structure, since the head element 3 is covered with the good conductor film 17, the head element 3 can be electromagnetically and electrostatically shielded from the external space. The S/N ratio improves because the noise from the source can be reduced.

Further, since the good conductor film 17 is formed to be exposed on the outer surface of the protective layer 5, it can be manufactured independently from the protective layer 5, which facilitates manufacturing and also facilitates ground connection.

In addition, the good conductor film 17 of this embodiment not only removes the vicinity A of the exposed portion of the honting pad 14, but also removes the straight portion B extending from there to the side end surface of the thin-film magnetic head. This provides a configuration in which the good conductor film 17 does not surround the terminal 15 for connecting the coil conductor layer. Therefore, noise caused by electromagnetic induction in the good conductor film 17 is less likely to enter the reproduced signal taken out from the terminal 15, and the S/N ratio is also improved from this point of view.

"Effects of the Invention" As explained above, according to the present invention, since a good conductor film covers the head element and is grounded, electromagnetic shielding and electrostatic shielding of the head element can be achieved, and it is possible to shield the head element from external space. Can reduce noise.

In addition, since the good conductor film is formed on the top surface of the protective film,
It can be manufactured separately from the protective film, and is easier to manufacture than a structure in which a good conductor film is embedded inside the protective film.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing one embodiment of the present invention, and FIG. 2 is a perspective view showing one embodiment of the present invention.
A cross-sectional view taken along the line ■-■ in the figure, and FIG. 3 is a detailed cross-sectional view of the head element. 1... Board, 3... Head element, 5...
...Protective film, 9 ...Coil conductor layer, 17...
・・Good conductor membrane, 18 earth terminal, 19−・ wire. Patent applicant: Alps Electric Co., Ltd. Representative Masataka Oka

Claims (1)

[Claims] A thin film magnetic head comprising a head element and a protective film covering the head element provided on a substrate, characterized in that a good conductor film is formed on the upper surface of the protective film, and this good conductor film is grounded. head.