JPH0489608A - Thin film magnetic head and manufacture of said head - Google Patents

Abstract

PURPOSE:To reduce the unnecessary dimension of gap depth (GD) and to improve the recording performance of the thin film magnetic head by providing more than two angles at the tip shape of an upper magnetic layer and reducing the angle only at one part of the tip of the upper magnetic layer without degrading the recording performance. CONSTITUTION:A tip angle theta1 formed between an upper magnetic layer 13 and a magnetic gap layer 7 is initially acute in the depth direction and made larger than an angle theta2 communicated to the angle theta1 or initially made acute and successively made larger afterwards, and at this part, the shape of the upper magnetic layer 13 is recessed upward. Thus, since the tip angle theta1 formed between the upper magnetic layer 13 and the magnetic gap layer 7 is made acute less than 30 deg. at a position where these two layers contact, the GD can be reduced. On the other hand, since the angle theta2 communicated to this tip angle theta1 is made larger or successively made larger, abnormal approach between upper and lower magnetic layers 13 and 6 and short-circuiting between the upper magnetic layer 13 and coil layers 9 and 11 can be prevented. Then, the GD can be reduced without damaging the performance of the thin film magnetic head.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a high performance thin film magnetic head, particularly to a thin film magnetic head having good recording performance and a method for manufacturing the same.

2. Description of the Related Art As the performance of magnetic disk drives increases, the thin film magnetic heads used therein are also required to have various improvements in performance.

Among these, in order to improve the linear recording density of magnetic disk devices, improving the recording ability of thin film magnetic heads on high coercive force media has become a particularly important issue.

A conventional thin film magnetic head will be explained below.

FIG. 4 is an external perspective view of a conventional thin film magnetic head. The device is formed on a ceramic substrate using thin film formation technology,
It is in the shape of a slider for a magnetic disk device.

In FIG. 4, 1 is a floating rail, 2 is a thin film magnetic head element, and 3 is a terminal. When a thin film magnetic head is mounted on a magnetic disk device or the like, a gimbal is attached to the floating rail 1 in parallel to the back side thereof. FIG. 5 is an enlarged front view of a conventional thin film magnetic head, in which 4 is an insulating layer, 5 is a magnetic layer, and the coil/I/layer is covered with these layers. FIG. 6 is an enlarged cross-sectional view of the tip of the thin film magnetic head taken along line a and / in FIG. 5. FIG. A lower magnetic layer 6. is formed on a ceramic substrate coated with an insulating material such as alumina. A magnetic gap layer 7 is formed, and a lower insulating layer 8 is further formed thereon. Lower conductor layer 9. Intermediate insulating layer 10. Upper conductor layer 11. Upper insulating layer 12. Upper magnetic layers 13 are sequentially laminated, and finally a protective layer 14 made of alumina or the like is provided.

The distance from the medium facing surface 15 of the thin film magnetic head shown in FIG. 6 to the position 16 where the lower magnetic layer 6 and the upper magnetic layer 13 face each other via the magnetic gear layer, that is, the gap depth (hereinafter abbreviated as GD) is the thin film magnetic head. It has a great influence on the performance of a magnetic head, and is the most important dimension, especially with regard to recording capacity.

The thin film magnetic head has a finite magnetic field generation region B (3 to 16 μm) consisting of a lower magnetic layer 6, an upper magnetic layer 13, and a magnetic gap layer 7 appearing on the medium facing surface 15, and upper and lower magnetic layers forming a magnetic circuit. 13゜6 is thin and the magnetic circuit is long compared to it (about 1 to 6 μm in the C region and 5 to 10 μm in the D region). The influence of GD size on recording performance is greater than that of GD. Therefore, the GD dimension of a normal thin film magnetic head is 0.
．． It is regulated to about 5 to 2 μm, and the smaller this dimension, the higher the recording performance. However, some thin-film magnetic heads actively use the shape effect (a phenomenon in which the reproduction output increases or decreases compared to an infinitely long three-dimensional head due to the relationship between the recording wavelength on the medium and the three dimensions) in the reproduction performance. Therefore, if the three dimensions change, the reproduction characteristics will change from the desired characteristics.

Therefore, the GD adjustment process must be completed before the slope where the dimensions of the upper magnetic layer 13 on the medium facing surface 15 change. Therefore, there is a dimension A that always remains among the GD dimensions, and this dimension creates a limit to the recording performance of a thin film magnetic head that utilizes the shape effect. Since the upper magnetic layer 13 grows almost parallel to the underlying surface on which the upper magnetic layer 13 is formed, the dimension thereof is proportional to the film thickness E of the upper magnetic layer 13 on the medium facing surface 15. The larger the 6/\-angle (hereinafter referred to as tip angle) θ that the upper magnetic layer 13 makes with the magnetic gap layer 7, the larger the absolute value of the dimension.

Problems to be Solved by the Invention However, in the conventional configuration described above, if the tip angle θ of the thin film magnetic head is set to 30 to 46 degrees, which is considered appropriate in the literature from the viewpoint of the generated magnetic field, and the film thickness E is set to 2 μm, the dimension to is 0.5 to 2 μm. In this dimension, set the GD dimension to 0.
．． When adjusting the thickness to 5 to 2 .mu.m, there is a problem in that the margin is reduced and the processing yield is significantly lowered, and the recording performance of the thin film magnetic head is hindered from being improved. On the other hand, in order to solve this problem, a structure in which the tip angle θ is made small as shown in FIG. 7 has been adopted. However, in this structure, in order to reduce the dimension, the tip angle θ between the upper magnetic layer 13 and the magnetic gear knob is made more acute, so the lower magnetic layer 6 and the upper magnetic layer 13 are brought too close together, resulting in leakage magnetic flux between the magnetic layers. The lower conductor layer 9. There was a problem in that the upper conductor N11 came too close to the upper magnetic layer 13, causing a short circuit with the upper magnetic layer 13 in region F in FIG.

The present invention has been made to solve the above-mentioned conventional problems, and an object of the present invention is to provide a thin-film magnetic head with reduced dimensions and improved performance, and a method for manufacturing the same.

Means for Solving the Problem In order to achieve this object, the present invention provides a method in which the tip angle between the upper magnetic layer and the magnetic gap layer is initially acute in the depth direction, and the subsequent angles are larger, or The angle is initially acute, and then gradually becomes larger, and the shape of the upper magnetic layer is concave upward at this portion.

Function: With this configuration, the CiD dimension can be reduced by making the tip angle between the upper magnetic layer and the magnetic gap layer an acute angle of 30 degrees or less at the position where these two layers touch, and this tip angle By making the angle larger or successively larger, it is possible to prevent abnormal approach between the upper and lower magnetic layers and short circuit between the upper magnetic layer and the coil layer.

As a result, the GD dimension can be reduced without impairing the performance of the thin film magnetic head.

Example An embodiment of the present invention will be described below with reference to the accompanying drawings.

The completed state of the thin film magnetic head is the same as that of the conventional example shown in FIGS. 4 and 5, so a description thereof will be omitted. FIG. 1 is a sectional view of a main part of a thin film magnetic head according to an embodiment of the present invention.

As shown in the figure, a lower magnetic layer 6 made of permalloy, amorphous or other magnetic material is formed on a ceramic substrate coated with an insulating material such as alumina, and an a/l layer is formed on it.
/Magnetic gap layer made of insulating material such as Mina7. 8. A lower insulating layer made of a photosensitive material or an insulator such as silicon dioxide (S 102 ). Lower conductive layer 9 made of conductive material such as copper. Intermediate insulating layer 10 made of a photosensitive material or an insulator such as Sio2. Upper conductive layer 11 made of a conductive material such as copper. Upper insulating layer 12 made of a photosensitive material or an insulator such as Sio2
, and then the top layer of insulation 9...-7 layers 16. Upper magnetic layers 13 made of permalloy, amorphous, or other magnetic materials are sequentially laminated, and are finally protected with a protective layer 14 made of an insulator such as alumina.

The top insulating layer 16 is added to the shape formed in a conventional thin film magnetic head, but the top insulating layer 16 is formed using a material with the same viscosity as the other insulating layers 8, 10, or 12. If resin is used, the angle between the magnetic gap layer 7 and the upper magnetic layer 13 will be larger than that of a conventional thin film magnetic head, resulting in an opposite effect. Therefore, we investigated the use of photosensitive resins with various viscosities, and developed the uppermost insulation layer 16.
It has been found that the appropriate viscosity of the resin used for this is 30 cp to 50 ap. The definition of this viscosity differs depending on the resin manufacturer, so the numerical value differs depending on each resin, but at least the resin used for the uppermost insulating layer 16 must have a lower viscosity than the resin used for the other insulating layers 8, 1o, or 12. Must be. As shown in FIG. 1, the cross-sectional shape of the thin-film magnetic head created as described above has a small angle θ1 at which the upper magnetic layer 13 contacts the magnetic gap layer 7 and 10 \-7, and a larger angle θ2 connected thereto. The tip region C of the upper magnetic layer 13 is configured with two types of angles, and these different angles can be smoothly connected. The thin film magnetic head thus formed can have an unnecessary dimension A included in the GD dimension smaller than that of a conventional thin film magnetic head, and the recording performance of the thin film magnetic head can be improved. The angle θ1 formed between the upper magnetic layer 13 and the magnetic gap layer 7 and the angle θ2 connected to the angle θ1
The position of the inflection point 19 up to is changed by adjusting the distance E between the tip position of the insulating layers 8 to 12 and the tip position of the uppermost insulating layer 16 and the viscosity of the resin used for the uppermost insulating layer 16. can do. For example, if the viscosity of the resin is 300
p, by setting the E dimension to 3 to 5 μm, θ
1 is 10 to 20 degrees, and the inflection point 19 is 1 to 2 μm.

As a result, the unnecessary dimension A in the GD dimension becomes 0 to 0.3 μm, so that the effective GD dimension can be reduced and the recording performance of the thin film magnetic head can be improved.

An inorganic insulating material such as S Lo 2 is used for the insulating layers 8 to 12.
An example of the manufacturing method in the case where 1.--- is shown in FIG.

After forming up to the upper insulating layer 12, as shown in FIG. 4A, an etching mask 17 is formed to control the shapes of the tips of the insulating layers 8-12. At this time, etching mask 1
Using a photosensitive resin or the like, the tip shape 18 of the magnetic gap layer 7 is made to have a small angle at a portion in contact with the parallel planes and a large angle connecting thereto.

Next, as shown in FIG.
In-beam etching with Ar etc. and CF4
The tips of the insulating layers 8 to 12 were made to have the same shape as the tip 18 of the etching mask 17 by reactive ion etching using a gas such as the following, and the cross-sectional structure shown in FIG. 3 was obtained.

Effects of the Invention As described above, the present invention provides at least two or more angles to the tip shape of the upper magnetic layer of a thin film magnetic head, and allows only a part of the tip of the upper magnetic layer to have an angle without deteriorating recording performance. By reducing , it is possible to reduce the unnecessary dimension (the dimension) of the GD dimension and improve the recording performance of the thin film magnetic head. Furthermore, the yield of GD adjustment processing can be improved by reducing the unnecessary dimension (the dimension) of the GD dimension.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of essential parts of a thin-film magnetic head according to an embodiment of the present invention, and FIGS. 3 is a sectional view of a main part of a thin film magnetic head according to another embodiment of the present invention, FIG. 4 is an external perspective view of a conventional thin film magnetic head, FIG. 5 is an enlarged front view of a conventional thin film magnetic head, and FIG. The figure is an enlarged sectional view of the main part of the tip of a thin-film magnetic head taken along a-a'i in Fig. 6, and Fig. 7 is an enlarged sectional view of the main part of a conventional thin-film magnetic head with a small tip angle. be. 6...Lower magnetic layer, 7...Magnetic gap layer, 8...Lower insulating layer, 9...Lower conductor layer, 1o...・Intermediate insulating layer, 11...
・Top conductor layer, 12...Top insulating layer, 13...
...Top magnetic layer. Name of agent: Patent attorney Shigetaka Awano and one other person

Claims (1)

[Claims] (1) A thin film consisting of a coil layer consisting of a lower magnetic layer, a magnetic gap layer, an upper magnetic layer, a lower insulating layer, a lower conductor layer, an intermediate insulating layer, an upper conductor layer, and an upper insulating layer. A thin film magnetic head in which an angle formed by an upper magnetic layer and a magnetic gap layer includes a first angle near the intersection thereof and a second angle larger than the first angle at a position away from the intersection. (2) The second angle is composed of an upper insulating layer and a magnetic gap layer, and the first angle is composed of an uppermost insulating layer and a magnetic gap layer formed covering at least an edge of the upper insulating layer. 2. A thin film magnetic head according to claim 1. (2) The thin film magnetic head according to claim 1 or 2, wherein the magnetic gap layer is made of an inorganic insulating material, and the uppermost insulating layer is a resin having a lower viscosity than the resins constituting the other insulating layers. (4) The magnetic gap layer, the upper insulating layer, the intermediate insulating layer, and the lower insulating layer are formed of an inorganic insulating material, and the inorganic insulating material constituting the magnetic gap layer covers the upper insulating layer, the intermediate insulating layer, and the lower insulating layer. 3. The thin film magnetic head according to claim 1, wherein the thin film magnetic head has an etching rate different from that of the constituent inorganic insulating material. (5) Step of sequentially forming a lower magnetic layer, a magnetic gap layer, a lower insulating layer, a lower conductor layer, an intermediate insulating layer, an upper conductor layer, and an upper insulating layer on a predetermined region on an insulating substrate; A process of forming an etching mask that becomes thicker in a concave shape from the intersection with the upper insulating layer except for the upper part, and a process of sequentially etching the upper insulating layer, the intermediate insulating layer, and the lower insulating layer on the magnetic gap layer. , a method for manufacturing a thin film magnetic head comprising the step of forming a protective layer after removing an etching mask.