JPH01317216A - Production of thin film magnetic head - Google Patents

Abstract

PURPOSE:To improve contact connection and the thickness accuracy of insulating films by forming the respective junctures of coils thicker by a prescribed thickness than the other parts and laminating the insulating layer thereon, then polishing the layer to flatten said layer until the junctures are formed flush with each other. CONSTITUTION:The coil material is so formed that the juncture 2a to the other coil and a terminal taking-out part 1a are formed as a projecting part and the other part is formed as a recess. The insulating layer is laminated on the coil material having such ruggedness so as to coat the recesses with said layer. The insulating layer is then so flattened that the juncture 2a and terminal taking-out part 1a of the laminated coil material are exposed. The exposed juncture 2a and the terminal taking-out part 1a are electrically connected. The thickness accuracy of the insulating layer film on the coil is improved in this way and the sure connection is executed.

Description

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

In particular, the present invention relates to the structure of the contact connection portion of a thin-film magnetic head multilayer coil and the center tap extraction.

[Conventional technology]

In order to compensate for the output waves caused by the decrease in track width due to the increase in magnetic recording density, there is a need to increase the number of filters in thin-film magnetic heads. A method that has high recording/reproduction efficiency and is suitable for high-density recording is a method in which the coil is multilayered and all intermediate taps are provided. In this case, it is necessary to provide an insulating layer between the coils in each layer and to connect the coils in each layer through through holes. As a conventional head of this type, for example, JP-A-56-58
There are thin film magnetic heads described in Japanese Patent Publication No. 124, Japanese Utility Model Application Publication No. 126408/1982, and Japanese Patent Publication No. 31768/1983.

FIG. 3 is a plan view showing a conventional thin film magnetic head coil section. In FIG. 3, for the sake of simplicity, the coil and the contact connection portion are shown as straight lines and rectangles, respectively, and the one interlayer insulating layer and the magnetic core are omitted. Figure 3 (a), (b),
(c+, (a+ are the first layer (lowest layer, second layer,
The third and fourth layers (representing each coil of the top layer, (I
a) is the first layer coil external terminal extraction part.

(,2a), (,2b, l is the first layer-second layer coil connection part, (3b).

(3 are the 2nd layer-3rd layer coil connection part, (2s, (2d)
) is the third layer-fourth layer coil connection portion, (4b) is the intermediate tap terminal area extension portion, and (5d) is the fourth layer coil external terminal extraction portion. The terminal extraction portions, that is, the contact connection portions (1a), (4b), and (5a) are connected to external current terminals (not shown).
The terminal from b) is an intermediate tap, and in the case of Figure 1, it is divided into 6 turns and 6 turns. Each layer coil has a connecting part (2
b) and the connection part (2C) are insulated, but they are connected by corresponding numbered contact parts. That is,
(2a) −+ (2b) , (3b) −(3
Two.

(2 - (2d) are connected respectively. The current is (1a
) → (2a) → (2b) → (4b) (middle tap) → (
The flow is as follows: 3b) → (3s → (2s) → (2d) → (5d). Each contact connection portion is connected by forming a through hole in the insulating film by photoetching.

[Problem to be solved by the invention]

As explained above, in conventional thin film magnetic heads, the center tap is located at the innermost circumference of the coil, the outermost circumference of the coil, or the outermost circumference of the coil! It comes from a position within Ill. Therefore, the number of laminated layers is limited to an even number in order to balance the reproduction voltage. Or.

The position of the intermediate tap is limited from above, and the number of laminated coils is limited to an even number in order to balance the reproduction voltage1.Also, the position of each laminated coil is not necessarily equal to the magnetic core. Since there is no total number of turns i
Sometimes just 1/2 is not enough to get the lance.

Furthermore, coils are determined by comprehensively considering playback voltage, recording efficiency, frequency characteristics, manufacturing cost, etc., but if the number of laminated layers is limited to an even number, then 1 For example, even if 3 layers are sufficient for overall performance, 4 layers This leads to an increase in manufacturing costs. The insulating layer between two layers is usually a photoresist, an organic material such as polyimide resin, or 5i02.

Inorganic substances such as Al2O3 are used. Inorganic materials are desirable from the viewpoint of linear expansion coefficient, thermal conductivity coefficient, etc., but there are difficulties in flattening the unevenness of the coil and forming through holes.

In particular, in the case of multilayer coils, as shown in Fig. 3, in the final terminal extraction process, the terminal extraction part (1a) of the first layer coil is
) are located on the bottom layer, and the number of terminals of the fourth layer coil (the raised portion (5d) is located on the top layer, and their heights are different. In other words, the insulating layer film thicknesses on the terminals are different.

For this reason, in the case of an inorganic insulating layer, when forming a through hole by etching, the end point differs significantly, making it impossible to ensure the required precision. Furthermore, even when an organic resin such as photoresist is used as the insulating layer, there is a problem in that the photoresist accumulates in the recesses, making photolithography difficult because the photoresist thickness differs between the terminal extraction parts (1a) and (5d). .

This invention was made to solve the above-mentioned problems, and allows the intermediate tap to be taken out from any position of all the coils, making it possible to obtain a well-balanced reproduction voltage without being limited by the number of laminated layers. An object of the present invention is to provide a method for manufacturing a thin film magnetic head. Furthermore, in connection with the above, it is an object of the present invention to provide a method for manufacturing a thin film magnetic head that can easily improve contact connection and insulation film thickness accuracy even when the number of laminated coils increases or when an inorganic material is used as an insulating layer. With the goal.

[Means to solve the problem]

A method of manufacturing a thin film magnetic head according to the present invention is as follows.

The connection part with other coils and the terminal extraction part are made convex parts,
A step of forming a coil material so that other parts of the coil have recesses, and a step of laminating an insulating layer on the coil material having the recesses and recesses so as to cover the recesses.

A process of flattening the insulating layer so that the connection part and terminal extraction part of the laminated coil material are exposed, and a process of electrically connecting all the exposed terminal extraction parts are performed.

[Effect]

A method of manufacturing a thin film magnetic head according to the present invention is as follows.

After each connection part of the coil is formed to be thicker than the others by a predetermined thickness and an insulating layer is laminated thereon, the heights of the connection parts are made uniform by flattening and polishing until each connection part is exposed. Since the point at which this connecting portion is exposed can be used as a guideline for the end point of polishing, and since the height of the connecting portions is the same, it is possible to easily obtain the accuracy of the insulation film thickness on the coil and the contact connection. Also.

As described above, since the intermediate tap can be taken out from any location of any coil, the degree of freedom in coil design is increased and an optimal design can be made depending on the purpose.

〔Example〕

A method of manufacturing a thin film magnetic head according to an embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a plan view showing the structure of each layer of a three-layer coil with a center tap of a thin-film magnetic head according to an embodiment.

Figure 2 is a cross-sectional view taken along the ■-n line, and is a cross-sectional view for explaining the manufacturing process of each layer. Figure 1 (al~tc) and Figure 2 (al~(c)) correspond to In Fig. 1, for simplicity, all coils and contact connections are shown as straight lines and rectangles, and the interlayer insulating layer and magnetic core are omitted.In Fig. 2, for simplicity, the coil (shaded Only the outermost and innermost peripheries are shown and the space between them is omitted, and the lower layer coil is also shown to show the outline of the process. Fig. 1 (a)
, (b) , (Ci represents each coil of the first layer (bottom layer), second layer, and third layer (top layer), terminal extraction portions, that is, contact connection portions (1a), (4t)) J
2 is connected to an external current terminal (not shown). The terminal from the contact connection part (4b) is an intermediate tap, and in the case of Figure 1, it is divided into 6 turns and 6 turns. Each layer coil has a connection part (2b) (except that there is insulation between the two).

Connected by corresponding numbered contacts.

That is, (2a) - (2b) (3b) - (3 are connected respectively, and (1a) - (ib) - (i and (4b)
-(4 are connected to each other. The current is (1 → (1
The flow is as follows: b) → (1a) → (2a) → (2b) → (4b) (middle tap) → (3b) → (3s → (2). In the figure, the third layer coil is connected to the lower layer middle tap. Location (4
c) It is arranged so as to avoid it. The middle tap connection point (4b) of the second layer coil is wider than the rest of this coil. Also, each connection point is thicker than other parts of the coil by a predetermined thickness n.

In the above configuration, the part of the coil where the intermediate tap is to be provided, in the case of Fig. 1, the contact connection part (4b, l k
It is sufficient to form the intermediate tap slightly wider and to avoid this part in the coil in the upper layer than this coil, that is, in the third layer coil shown in FIG. It can be installed at the coil position. Next, a method for connecting each coil will be explained based on FIGS. 1 and 2. In Figure 1 and Figure 2 (a), the connection part (1
a) and (2a) are made thicker than the other parts of the coil by a predetermined thickness, a first layer coil is formed as a coil material so as to have unevenness, and the concave portions are covered on top of the first layer coil (Fig. 2). Insulating layers are laminated as shown in .Next, the connection parts (1a,), (2
2 (dotted line Ia in al.
The first layer shown in FIG. 1(a) is manufactured by flattening and polishing to the Ia line. Next, in Figures 1 and 2 (1)),
A second layer coil is formed, and at this time, the terminal lead-out portion (1b) of the first layer coil is also laminated by the thickness of the coil.

The connection part (3b) between the second layer coil and the third layer coil, the intermediate tap takeout part (4b), and the terminal takeout part (1b) of the first layer coil are simultaneously increased in thickness to a predetermined thickness to have unevenness.
Form a second layer coil. An insulating layer is laminated thereon as shown in FIG. 2(b). This rear connection part (3b),
The other layers are planarized until (4b) and (1b) are exposed, that is, up to the dotted line 1b-1b in FIG. 2(b). 1 and 2 (in the same way for the third layer coil of CL, the terminal extraction part (one, 1.2'-), After forming, an insulating layer is laminated and planarized and polished until each terminal extraction part is exposed.There are two methods for planarization: mechanical polishing;
Or you can use the etch pack method. In either case, by using the point at which the thickly formed convex connection portion is exposed as a guideline for the end point of polishing, the accuracy of the insulating film thickness on the coil and the contact connection can be easily obtained. The thickness of the coil portion is increased by a predetermined thickness after the coil is formed.

Alternatively, a coil film of a predetermined thickness may be formed in advance at the amplification location. Next, take out the terminals (1a) and (2).

(4C) Connect to an external current terminal (not shown).

In addition, in the above embodiment, the middle tap is set to the second layer in the three-layer coil.
Although we have shown the case where the regenerated output is obtained by taking out the coil from the layered coil, the number of coil layers is not limited to three layers, the coil division is not limited to one to one, and it is possible to Shedding can also be done from any layer of coils. For this purpose, for example, a 48 full turn is used for playback.

It is also possible to use 1o turn using the intermediate tap during recording. Talented. Even when the method for manufacturing a coil connection portion in the above embodiment is applied to a coil without an intermediate tap, it is effective in terms of connection reliability, insulation film thickness accuracy, flattening end point detection, coil multilayering, etc.

Further, the insulating layer is not particularly limited, and can be similarly applied to an Al2O3 film, a diamond film, a silicon nitride film, an organic resin film, etc. [Effects of the Invention] As described above, according to the present invention, In a product that has all multilayer coils, the process of forming the coil material so that the connection part with other coils and the terminal extraction part are convex parts, and the other parts of the coil are concave parts, and the process of forming concave parts in the coil material having this concave and convex part. A process of laminating an insulating layer so as to cover the coil material, a process of flattening the insulating layer so that the connection part and terminal takeout part of the laminated coil material are exposed, a process of electrically connecting the exposed connection part and the terminal takeout part. By applying.

This has the effect of improving the accuracy of the thickness of the insulating film on the coil, and eliminating the need for the subsequent process of forming through holes in the insulating film. In addition, depending on the type of insulating film (1 tin can be applied, even if multiple layers of coils are laminated, the height of the connection part can be made uniform without being limited by the number of laminated layers, so the same process can be simply repeated. In addition, since the connection part is flattened, photolithography can be performed easily and with high precision, and the connection can be made reliably.Furthermore, an external terminal extraction part can be formed at any location of any coil. This has the effect of providing a method for manufacturing a thin-film magnetic head that increases the degree of freedom in coil design and enables optimum design depending on the purpose.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing the structure of a coil according to a method of manufacturing a thin film magnetic head according to an embodiment of the present invention. FIG. 2 is a sectional view for explaining the layer manufacturing process corresponding to FIG. 1. FIG. 3 is a plan view showing a coil of a conventional thin film magnetic head with an intermediate tap. (1a) is the terminal extraction part of the first layer coil, (1b
). (1 is the thickened part, (2a), (2b) is the connection part between the first layer coil and the second layer coil, (2 is the terminal extraction part of the third layer coil, (3b, lJ3 is the third layer coil) The connection part between the second layer coil and the third layer coil, (4b, 1. (4 is the intermediate tap extraction part. In Figure 9, the same reference numerals indicate the same or equivalent parts.

Claims (1)

[Claims] In a product having a multilayer coil, a step of forming a coil material so that the connecting portion with another coil and a terminal extraction portion are convex portions, and other portions of the coil are concave portions; a step of laminating an insulating layer so as to cover the recessed part, a step of flattening the insulating layer so that the connection part and the terminal takeout part of the laminated coil material are exposed, and a step of flattening the insulating layer so that the connection part and the terminal takeout part of the laminated coil material are exposed. A method of manufacturing a thin film magnetic head, the method comprising performing an electrical connection process.