JPS6246411A - Production of thin film magnetic head - Google Patents

Abstract

PURPOSE:To stabilize a magnetic conversion characteristic by removing only the 2nd insulator except the 1st insulator among insulator layers constituting a magnetic gap part, then forming an upper magnetic material layer by film formation and constituting part of the magnetic gap of the 1st insulator. CONSTITUTION:The front magnetic gap is formed of the insulator layers 2, 4 by making combination use of wet etching and dry etching. First, the insulator layer 2 is completely etched by dry etching, then the insulator layer 4 is completely removed by dry etching except a slight thickness. The magnetic gap 7 is formed at the point of the time when the insulator layer 4 is thoroughly removed by wet etching. The insulator layer 7 is constituted by using SiO as the 1st insulator and the insulator layer 4 is constituted by using Al2O3 or SiO2 as the 2nd insulator. The accuracy of a gap width is thus stabilized and the process for production is made easy, by which the magnetic conversion characteristic is stabilized.

Description

[Detailed Description of the Invention] [Technical Field] The present invention relates to a method for manufacturing a thin-film magnetic head, and more particularly, to a lower magnetic layer, a conductive layer is formed through an insulating layer, and a two-part magnetic layer is formed on the lower magnetic layer through an insulating layer. The present invention relates to a method of manufacturing a thin film magnetic head formed by forming layers.

[Prior Art] Conventionally, such a thin film magnetic head has a structure as shown in FIG. In the figure, the magnetic head is shown as a three-wound thin film magnetic head with a bias line.

Such a magnetic head is manufactured as follows. That is, a magnetic substrate 6 serving as a lower magnetic layer forming a part of the magnetic circuit of the magnetic head. A conductive layer 5 is formed by depositing a highly conductive metal using a method such as vapor deposition, electrodeposition, or sputtering, and is formed into a predetermined pattern using a photoetching technique. An insulating layer 4 is formed thereon, and then a conductive layer 3 is patterned thereon. Further, an insulator layer 2 is formed thereon. The conductive layer 5 thus formed is used for a bias line, and the conductive layer 3 is used for a signal coil.

Here, an upper magnetic layer l made of a material such as permalloy is formed so as to cover a part of the conductive layer 3.5 via the insulating layer 2.4.
is formed using film-forming methods such as evaporation, electrodeposition, and sputtering, as well as photoetching technology to form a thin n9! It constitutes an 81 air head.

After forming the insulating layer 2 to form the magnetic gap 7 in such a thin film magnetic field, the insulating layer 2.4 at the front part is removed by wet or dry etching down to the lower magnetic substrate 6. . Then, an insulating layer is formed as a magnetic gap 7, and then an upper magnetic layer 1 is formed.

When manufacturing a magnetic head using this method, the insulator layer 2
．． When dry etching is used to etch the substrate 4 down to the lower magnetic substrate 6, there is a disadvantage that the surface of the lower magnetic substrate 6 is attacked, making the substrate surface rough and uneven. When etching is used, the substrate surface is similarly attacked □ 1 by the etching solution, and side etching is performed on the insulator layer 2.4 by 1.2 □, 6. (7) -j-/7 pieces. -Kayoyo 4
Even if a 34-way gap 7 is formed, the gap accuracy deteriorates because the substrate surface is rough, resulting in poor magnetic conversion.
1: There were drawbacks such as unstable characteristics.

[11th point] 11' Therefore, the object of the present invention is to solve the above-mentioned conventional problems 1:
1. This was done to eliminate the drawbacks of magnetic:
Provided is a method for manufacturing a thin film magnetic head in which gaps can be formed with high precision and stable magnetic conversion characteristics can be obtained.

The porpose is to do.
1□ [Structure of the Invention] In order to achieve this object, the present invention provides a magnetic substrate, in which an insulating layer made of a first insulator, a conductive layer, and an insulating layer made of a second insulator are sequentially formed. Then, only the second insulator was removed leaving the first insulator □, and then an upper magnetic layer was formed, so that a magnetic gap portion □ was formed by the first insulator.

[Example] Next, a method of manufacturing a magnetic head according to the present invention will be described with reference to FIGS. 2 and 3.

First, as shown in FIG. 2, a magnetic gap layer is formed on the surface of the mirror-wrapped magnetic substrate 6.
An insulator layer 7 made of a material such as iO is deposited.

: , Wow, l'<y p'4rorJ:, nlJ kaa □ It's ok.

□ A conductive layer 5 that will become a bias line is formed on it, and □
A predetermined pattern is formed using photo-etching technology. An insulator layer 4 is formed thereon, and then a conductor layer 3 that will become a signal coil is patterned. Subsequently, an insulator layer 2 is formed thereon, and the process moves to a front magnetic gap forming step.

The front magnetic gap is formed by wet etching and dry etching the insulator layer 2.4 as shown in FIG. The reason why dry etching is used in combination with wet etching instead of wet etching is to improve step coverage. First, the insulator layer 2 is completely etched by dry etching, and the insulator layer 4 is removed by dry etching, leaving about 0.5 gm of the insulator layer 4.
Subsequently, the remaining insulator layer 4 is completely removed by wet etching. The reason why 0.5 pLm of the insulating layer 4 is left is that unevenness occurs during dry etching due to etching non-uniformity such as crystal grain boundaries of SiO2, and this unevenness is created to prevent the magnetic gap 7, which is the insulating layer, from being attacked. Slightly more insulator layer 4
: To leave it behind.
□This wet etching removes the insulator layer 4.
□A magnetic gap 7 is formed when all 1□ is removed, and at this time, the insulator layer 4.7 is wetted.
□ Selectivity by etching is required. like this
If wet etching is performed on □, even if the insulator layer 4 is uneven, a smooth film can be obtained because the magnetic gap, which is the insulator layer 7, is selective. Thin Il! Complete the Jr Ki head.

The insulator constituting this magnetic gap may be SiO alone, or may be a combination of SiO and SiO2 to form an insulating layer 4 of SiO2.The magnetic gap manufactured in this way has less roughness on the SiO surface. Gap accuracy becomes stable.

In the above embodiment, the insulator layer 7 was formed using SiO as the first insulator, and the insulator layer 4 was formed using SiO2 as the second insulator. is Si
It is not limited to O, SiO2, and the first. For example, selective etching may be performed between the second insulators. SiO, AJ220 as the second insulator, respectively
3+, TiN, SiO2, etc. are considered.

[Effect] As explained above, according to the present invention, only the second insulator is removed while leaving the first insulator out of the insulating layer constituting the magnetic gap portion, and then the upper magnetic layer is formed. However, since a part of the magnetic gap is constituted by the first insulator, the accuracy of the gap width is stabilized, the manufacturing process is facilitated, and a thin film magnetic head having stable magnetic conversion characteristics can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing the structure of a conventional thin-film magnetic head, and FIGS. 2 and 3 are cross-sectional views showing a method of manufacturing a magnetic head according to the present invention. ■...Top magnetic layer 2.4...Insulator layer 3...
・Signal coil 5...Bias wire 6...Magnetic substrate 7...Magnetic gap Figure 1

Claims (1)

[Claims] 1) A method for manufacturing a thin film magnetic head comprising forming a conductive layer on a lower magnetic layer via an insulating layer and forming an upper magnetic layer thereon, wherein a conductive layer is formed on the lower magnetic layer. An insulating layer made of one insulator, a conductive layer, and an insulating layer made of a second insulator are sequentially formed, and only the second insulator is removed leaving the first insulator, and then an upper magnetic layer is formed. A method for manufacturing a thin-film magnetic head, characterized in that the first insulator constitutes a magnetic gap portion. 2) The first insulator is SiO, and the second insulator is Al_
2. The method of manufacturing a thin film magnetic head according to claim 1, wherein the thin film magnetic head is made of 2O_3 or SiO_2.