JPH0589436A - Thin-film magnetic head and production thereof - Google Patents

Abstract

PURPOSE:To improve the efficiency of a production operation by forming plural tracks of magneto-resistance type heads for reproducing on one surface of a substrate and forming induction type heads for recording on the other surface of the substrate at the same track pitch as the track pitch of the heads for reproducing. CONSTITUTION:The plural tracks of the magneto-resistance type heads A for reproducing are formed on the 1st surface of the substrate 1 consisting of an oxide magnetic material and the induction type heads B for reproducing are formed on the other surface of the substrate 1 at the same track pitch as the track pitch of the head A for reproducing. The thin-film magnetic head is produced by aligning by using a photomask arranged with the tracks of the mask to be the reference of the head A for reproducing and the mask to be the reference of the heads B for recording so as to be one to one on the front and rear surfaces of a wafer to align these tracks at the time of forming the above-mentioned heads on both surfaces of the substrate 1. The patterns varying with the front surface and the rear surface are formed with good accuracy within the same chip in this way.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multi-track thin film magnetic head integrally provided with a reproducing magnetoresistive head and a recording inductive head, and further to improving the efficiency of its manufacturing method.

[0002]

2. Description of the Related Art In a device such as DAT or DCC for recording / reproducing data on a magnetic medium with high density, a multi-track thin film magnetic head is used to increase the recording density. The thin film magnetic head used for such an application is generally a combination head (combination type head). The combination type head is a unit in which an inductive thin film head is used as a recording head and a magnetoresistive thin film head is used as a reproducing head, and these are integrally joined.

FIG. 3 shows a block diagram of a conventional combination type head. In this combination type head, the magnetoresistive head portion A and the inductive head portion B are separately manufactured, and the spacer glass 20
It is joined through. Both the magnetoresistive head portion A and the inductive head portion B have the same structure as a single thin film magnetic head. That is, the magnetoresistive head A has an upper yoke, a bias conductor, a magnetoresistive element portion, etc. formed on a substrate and covered with a protective plate. Further, the induction type head portion B is formed by forming a gap insulator, a magnetic circuit portion, and a coil portion on a substrate.

[0004]

However, in the conventional combination type head, since the recording head portion and the reproducing head portion are manufactured and joined separately, the manufacturing process as shown in FIG. 4 is required. It was

For this reason, it is necessary to separately perform the cylindrical polishing work after the line division, and it has been extremely difficult to perform alignment for track deviation and azimuth adjustment during joining. Further, there is a drawback that the yield is reduced because it is necessary to divide the wafers in both head parts into rows, select and bond the non-defective products, and further remove defective products at the time of bonding.

It is an object of the present invention to provide a thin film magnetic head and a method for manufacturing the same which solve the above problems by simultaneously forming a recording head and a reproducing head on both sides of one substrate.

[0007]

According to a first aspect of the present invention, a plurality of reproducing magnetoresistive heads are formed on the first surface of a substrate made of an oxide magnetic material, and the other surface of the substrate is formed. In addition, a plurality of recording induction type heads are formed at the same track pitch as the reproducing head.

The invention according to claim 2 of this application is characterized in that a photoresist of the same pitch is applied to both surfaces of a substrate made of an oxide magnetic material, and a pattern is formed by a double-sided alignment method.

[0009]

The thin film magnetic head of the present invention is a combination type head, but the reproducing head is formed on one surface of one substrate,
The recording head was formed on the other surface.

When manufacturing such a thin film magnetic head, a reproducing head and a recording head are simultaneously formed on both surfaces of a substrate. At the time of molding, a pair of a front surface and a back surface of the wafer are paired so that tracks of a mask (for example, a bias lead forming pattern) serving as a reference of the YMR head and a reference mask (for example, a lead layer forming pattern) of the recording head are aligned. The problem can be solved by performing alignment using a photomask arranged so as to be 1. That is, the equipment for performing such alignment is a general equipment as a double-sided aligner.
For example, a technique of accurately forming different patterns on the front surface and the back surface in the same chip in a power device such as a thyristor or a triac is a method widely used industrially as a known technique.

In this way, if the pattern formation of the first layer of the recording head chip and the reproducing head chip is performed in the initial process, the pattern formation of the second and subsequent layers of each head is based on the reference of the first layer. If the pattern is matched so as to match the pattern, a desired head can be accurately manufactured.

[0012]

1 is a sectional view of a combination type head according to an embodiment of the present invention. This combination type head is made of Fe-Ni.
The YMR head portion A is formed on one side (upper side) of the ferrite substrate 1, and the induction type head portion B is formed on the other side (lower side). The YMR head portion A is formed by forming the upper yoke 9, the bias lead 11 and the magnetoresistive effect element portion 10 on the substrate 1 and covering them with the protective plate 14 as in the conventional case.
Similarly to the conventional case, the induction type head portion B is also formed by forming two layers of coil lead patterns 5a and 5b and the upper magnetic pole 4 sandwiching the gap layer 3 on the substrate 1 and then covering with the protective plate 8. In this way, the YMR head portion A and the induction type head portion B are integrally formed on both surfaces of one substrate 1.

When manufacturing this combination type head, first, the bias lead forming pattern 11 of the YMR head A is formed.
And the first layer coil pattern 5a of the inductive head B are simultaneously formed by the required number of tracks so that the tracks match each other. A double-sided alignment exposure device is used for pattern formation. Both pattern materials are Al-Si, Al-C
It can be formed simultaneously by wet etching after forming a pattern by a photolithography process by setting a common material such as u and a common film thickness and processing accuracy. Next, the induction type head B having a margin in the upper limit of the film forming temperature and the temperature of the heat treatment step is formed on the lower side of the substrate 1. Further, the YMR head portion B whose temperature upper limit value is severely limited is formed on the upper surface. As a result, a wafer is completed in which the multi-track type thin film head chips in which the recording / reproducing thin film heads are accurately arranged at the same pitch are formed on both sides.

This wafer is formed into the magnetic head shown in FIG. 1 by the working steps shown in FIG. First, glass frit is applied to both surfaces and flattened by heating (n1),
The protection plates 8 and 14 are bonded (n2). Next, each row is divided (n3), and the medium sliding surface is line-ground (n4). When the grinding is completed, the surface is further smoothed (tape wrap) so that the magnetic tape can slide easily (n
5). After that, it is cut into chips (n6), assembled on a support tool (parts assembly: n7), wire bonded to an FPC (n8), and the head and tape guide are assembled together with other parts such as a read-ahead head (n9). )Complete.

Thus, as compared with the conventional combination type head manufacturing process (FIG. 4), the combination process is completely unnecessary, and the head 1 against the track deviation and azimuth rubbing is eliminated.
It is possible to eliminate the need for individual adjustment steps.

[0016]

As described above, according to the present invention, the combination process can be omitted, and the work for adjusting the head pitch and azimuth is not required, so that the manufacturing work can be made extremely efficient. The yield can also be improved.

Also, the cylindrical polishing process is performed only once,
Since the conventional double chevron shape is changed to a single chevron shape, spacing loss with the medium is also reduced. This makes it easy to set the center of the head at the center of the pad portion of the cassette tape.

Further, conventionally, it was necessary to use two expensive oxide magnetic material wafer substrates, but in the present invention, it is possible to use only one substrate, so that productivity can be improved and cost can be reduced.

[Brief description of drawings]

FIG. 1 is a sectional view of a combination type head according to an embodiment of the present invention.

FIG. 2 is a flowchart showing a part of a manufacturing process of the combination type head.

FIG. 3 is a sectional view of a conventional combination type head.

FIG. 4 is a flowchart showing a part of a manufacturing process of a conventional combination type head.

[Explanation of symbols]

 A-YMR head part B-Induction type head part 1-Substrate 5a-First layer coil pattern 11-Bias lead pattern

Claims (2)

[Claims] 1. A reproducing magnetoresistive head having a plurality of tracks is formed on a first surface of a substrate made of an oxide magnetic material, and a recording induction type head is the same as the reproducing head on the other surface of the substrate. A thin film magnetic head having a plurality of tracks formed by a track pitch. 2. A method of manufacturing a thin-film magnetic head, characterized in that photoresist having the same pitch is applied to both surfaces of a substrate made of an oxide magnetic material, and a pattern is formed by a double-sided alignment method.