JPS63113812A - Manufacture of thin film magnetic head - Google Patents

Abstract

PURPOSE:To raise the reliability, and also, to obtain the high density by forming a conductor coil by embedding a metallic film into the groove of an insulating film which is formed in advance, so that insulating layer can be filled exactly between coil wires. CONSTITUTION:An insulating film 2 is formed by a prescribed film thickness on a substrate 1, and a photoresist pattern 3 is formed thereon. Subsequently, by using the photoresist pattern 3 as a mask material, a groove 20 is formed on the insulating film 2 by dry method. This groove 20 is the same pattern as a pattern of a conductor coil. Thereafter, the photoresist is eliminated by etching, and on the whole surface of the insulating film 2, a plating surface 4 is formed. A metallic film 5 which becomes the conductor coil is formed on its whole surface by a plating method, and thereafter, its whole surface is eliminated to the insulating layer formed part by an etch-back method, and a coil pattern is formed. In such a way, the metallic film 5 is formed in the groove 20 without filling a resin between the coils, thereafter, the generation of an air-foam, based on the fluidity failure of the resin can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for manufacturing a thin film magnetic head, and particularly to the formation of a coil and an insulating film of a thin film magnetic head.

[Conventional technology]

A conventional thin film magnetic head for magnetic disk drives is described in Nikkei Electronics, July 7, 1980 issue.

] As described on pages 10 to 111, the conductor coil is formed by a plating method, and the insulating film is formed from a thermoset photoresist, which is an organic resin. In such a thin film magnetic head for a magnetic disk device,
In order to achieve high-density magnetic recording, it is necessary to form high-density coils in limited areas. In order to achieve high coil density, a fine structure is required, for example, such that the distance between the spaces between each turn of a multi-turn coil is 2 μm or less. In this configuration, since a hardened photoresist is used as the insulating film, due to the thermal fluidity of the resin, the space formed between each winding of the coil is filled with the resin, and the thin film magnetic The head is configured.

However, there is a problem in that a film made of hardened photoresist has poor heat resistance.

An example of using polyimide resin as an insulating film with improved heat resistance is IE, Transaction on Magnetics, MAGE-15, No. 161.
Pages 6 to 1618 (1979) (IEEE T
rans, Magn, MAG-15゜1616~1
618 (1979)).

[Problem that the invention attempts to solve]

However, according to the present inventors' study, the above-mentioned conventional technology
No consideration has been given to increasing the density of the coil, making it difficult to fill the spaces between the coils with polyimide resin, which serves as an insulating layer, without air bubbles. This is because the fluidity of the resin is poor. therefore.

There is a problem in that the reliability of the magnetic head is reduced due to air bubbles in the insulating layer due to the remaining filling.

In addition, since an insulating layer is formed between the coils and the coils, unevenness of the insulating layer occurs on the surface of the formed insulating layer due to the step of the coil, and if left as is, the magnetic properties of the magnetic film formed on top of the insulating layer will deteriorate. Therefore, the above-mentioned conventional technique requires a step of flattening the surface, making the process complicated.

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for manufacturing a highly reliable thin-film magnetic head with high density through a simple process by reliably filling an insulating layer between coil wires. .

[Means for solving problems]

In order to achieve the above object, the present invention has a conductor coil pattern formed by laminating an insulating film on a substrate, and having a pattern in which conductor coils of a predetermined shape are arranged alternately at a predetermined interval through an insulating part. In the method of manufacturing a thin film magnetic head by forming a thin film magnetic head in the insulating film, a groove pattern forming step of forming in advance a groove corresponding to the shape of the conductor coil in the insulating film in the same pattern as the conductor coil pattern; a coil pattern forming step of forming the conductor coil pattern by filling the groove with a metal that will become the conductor coil so that the coils are insulated from each other; This method of manufacturing a thin film magnetic head is characterized by comprising an insulating film forming step of forming an insulating film.

[Effect]

According to the present invention, a thin film magnetic head without air bubbles in the insulating film between the coils can be created by embedding a metal film into the grooves of the insulating film that has been previously formed to form a conductive coil. You can do it.

In addition, when forming an insulating film on top of the conductor coil after forming the conductor coil, the surface can be flattened, so unevenness on the surface of the applied insulating film can be reduced, and the insulating film can be formed on top of it in the next step. It is possible to maintain good characteristics of the magnetic film.

〔Example〕

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

FIG. 1 schematically shows the steps involved in forming a conductor coil in the present invention. The figure shows a cross-sectional view of the a-air head. For the purpose of explanation, it is assumed that the magnetic film etc. formed on the substrate are included in the substrate 1 in the drawing.
3 shows a conductor coil and an insulating layer embedded in the conductor coil.

The steps follow the following order:

(1) An insulating film 2 is formed to a predetermined thickness on a substrate 1 (FIG. 1 (1)).

(2) Form a photoresist pattern 3 on the insulating film 2. An organic resin or an inorganic film can be used as this insulating film ((2,) in FIG. 1).

(3) Using the photoresist pattern 3 as a mask material, a groove 20 is formed on the insulating film 2 by a dry method (FIG. 1 (3))
. The grooves are formed in the same pattern as the conductor coil.

The groove 20 can be formed into a desired shape (size, height, thickness, etc.) by using photoresist and its etching. Although the grooves 20 can be formed by mechanical processing, this is not sufficient to form a fine pattern. Therefore, etching is usually preferable.

(4) Etch and remove the photoresist (see Figure 1 (
4)).

(5) Form a plating base film 4 on the entire surface of the insulating film 2 (
Figure 1 (5)).

(6) A metal film 5 that will become a conductor coil is formed by plating on the entire surface (FIG. 1 (6)). As a result, a metal film is formed all over the insulating film including the inside of the groove 20, and the unevenness of the surface becomes smaller and flat compared to the unevenness of the insulating film. The reason why the metal film 5 is formed on the entire surface is as follows. Although it is possible to form a metal film only within the area 120, this is usually difficult. Therefore, as will be described later, a metal film was formed on the entire surface, and this metal film was removed by a so-called etch-back method to form a coil pattern.

(7) This entire surface is removed by an etch-back method up to the portion where the insulating layer will be formed. Then, the connection portions of the conductors formed above the grooves are removed so that the conductors are not connected by the metal film, and a coil pattern is formed (FIG. 1 (7)).

(8) An insulating film 2 is placed on the conductor coil thus formed.
1 is formed, and the conductor coil forming process is completed (FIG. 1 (8)).

According to the above process, between the plated metal films (between the coils)
Since the groove 20 is not filled with resin and a metal film is formed inside the groove 20, it is possible to prevent air bubbles from being entrained due to poor fluidity of the resin.

Next, specific examples will be described.

Figure 2 shows an example in which polyimide resin, which is an organic resin, is formed as an insulating film 2 on a substrate 1 (Figure 2 (2)
). As the polyimide resin, PIQ (polyimide isoindoquinazolinedione, trade name, manufactured by F1 Tatekasei Co., Ltd.) was used. Next, a groove for forming a coil is formed using a dry method. Here, the dry method includes methods such as plasma etching method and ion beam etching method. In either method, the pattern width can be narrower and the pattern can be formed deeper than in the chemical etching method using a solution, so that coils can be formed with high density.

In FIG. 2(1), an insulating film made of P IQ is formed on the substrate 1-A. Next, a photoresist pattern 3 is formed as shown in (2). The photoresist used here is Microposit 1.300 (trade name), which is a novolac positive type photoresist because of its good pattern accuracy.

(Sibley Fast Co., Ltd.) can be used, but the cross-sectional shape of this photoresist pattern is a trapezoid with a wider width closer to the surface of the insulating film 2.

Using the thus formed photoresist pattern as a mask, PIQ is etched by a dry method. As for the etching method at this time, ion beam etching using 02 gas has good pattern accuracy and allows stable etching. At this time, since the photoresist used as a mask material is also etched at the same time as the PIQ film is etched, the height and width are reduced (see Figure 2 (3).
)).

Since the photoresist and PTQ are etched at the same time, the initial film thickness of the photoresist is formed to be thicker than the depth of the groove 20 in the insulating film so that the photoresist remains on the insulating film 2 even after ion beam etching. Film thickness.

Subsequently, only the photoresist 22 is removed using a photoresist stripping solution, and a groove 20 for forming a coil is formed in the insulating film 2-1 (FIG. 2 (4)).

At this time, if only photoresist is used as the mask material,
During etching, the side walls of the photoresist are also etched at the same time, so the cross-sectional shape of the groove 20 in the insulating film 2 becomes tapered as shown in FIG. 2(4). Therefore, in order to form a high-density coil, it may be necessary to rotate the coil. That is, when forming a high-density coil pattern, adjacent grooves may be connected.

Therefore, in order to form a high-density coil by increasing the taper angle of the cross-sectional shape of the insulating film, it is preferable to etch the insulating film 2 not only using a photoresist as a mask but also using a metal film as a mask. A metal film 14 is formed on the insulating film shown in FIG. 3(1), an example of which is shown in FIG.
A photoresist pattern 3 is formed thereon. As shown in FIG. 3(2), this photoresist pattern is used as a mask, and the metal film 14 used as a mask is first etched. When etching the insulating film 2 by a dry method, an effective method for improving pattern accuracy is to use an ion beam etching method using Oz gas to etch the organic films P and IQ. . The metal film 14 used as a mask material at this time is chromium, molybdenum, nickel, etc., which have high resistance to oxygen ion beam etching.

Various metals can be used.

After forming the metal film pattern in this way,
), the grooves 20 are formed in the insulating film using the 02 gas ion vino N etching method, and then.

By removing the remaining photoresist and the metal film of the mask material, a groove is formed on the insulating film as shown in FIG. 3(4).

Next, as shown in FIG. 4, a coil is formed in the groove formed on the PIQ.

A method for forming the metal film of the coil by electroplating will be described. As shown in Figure 4 (1), the PI with grooves formed
A plating base film 4 is formed on the entire surface of the insulating film starting from Q.

The plating base film has poor adhesion between the PIQ and the metal film that will become the conductor coil, so the metal film is not connected to the PI through the plating base film.
This is provided for adhesion to Q. This plating base film is made by depositing, for example, Cr on PIQ (substrate) using a vapor deposition method such as sputtering, and then
It is formed by depositing u on Cr using a vapor deposition method, for example, a sputtering method. At this time, Cr is P
The IQ and Cu are bonded together, and the Cu is used to bond Cr and the metal film that will become the conductor coil. Among plating base films, the former is used.

Besides Cr, Ti, Ni, Mo, Ta, etc. can be used. Also, as the latter of the plating base films, C
In addition to u, Ni, Au, etc. can be used.

A conductive metal such as Cu is electroplated on this base film.

In addition to Cu, Au and Ni may be used.

When forming the metal film 5, the thickness of the plating film 4 (Cu film) makes it possible to reduce the unevenness of the plating film surface 5 compared to the step of the PIQ groove 20. Next, this entire plating film is etched back. In other words, Figure 4 (3)
As shown in FIG. 2, the entire surface of the metal is etched until an insulating layer surface 23 is exposed, so that the coils are insulated from each other and one surface is planarized. Finally, a PIQ film is formed on the surface to complete the formation of the coil pattern. At this time, since the space between the top surface of the coil and the insulating film 23 is flattened, the surface of the PIQ formed on the top is formed flat, which prevents deterioration of the magnetic properties of the magnetic film formed on it in a later process. It can be prevented.

The etch-back method shown in FIG. 4(3) will be explained below.

As the dry etchback method, a sputter etching method or an ion beam etching method is used. As explained in FIG. 4, the etch-back method involves forming a metal film surface until it becomes flat, and then etching the entire surface to set it back. However, the metal film 5
In order to form a metal film until the surface becomes flat, it is necessary to form the metal film thickly. As a method that does not require making the metal film thick, there is a method shown in FIG. That is, even if there are irregularities on the surface of the metal film 5, as shown in FIG.
By flattening the entire surface as shown in FIG. 5(2) and then etching back the entire surface, the surface of the coil embedded in the insulating film can be made flat as shown in FIG. 5(3).

At this time, in order to directly transfer the flatness of the applied organic resin to the formation of the coil, it is preferable to make the etching speed of the organic resin and the metal film the same.

For example, C11 is used as the metal film and PI is used as the insulating film.
The etching rate using Q will be explained. FIG. 6 shows the difference in etching rate between Cu and PIQ in the ion beam etching method using a mixed gas of argon and oxygen as the reaction gas.

According to FIG. 6, as the amount of oxygen increases, the etching rate of PTQ increases, the etching rate of Cu decreases,
The etching rates of Cu and PIQ can be kept constant. By selecting such conditions, the surface after the etch bag can be made flat.

As a method other than the etch-back method, a method of mechanical polishing can also be considered. for example.

As shown in FIG. 7(1), even if the metal surface has an uneven surface, by polishing the substrate surface, the metal film surface can be made flat as shown in FIG. 7(2).

Furthermore, as shown in 3) in FIG. 7, the coil pattern 24 is polished until the insulating film 23 appears on the surface.
Be able to complete. This method has the effect of avoiding an increase in the number of steps and high manufacturing costs due to the use of a vacuum device such as a dry method.

In this embodiment described below, an example was described in which an organic resin was used as the insulating film 2, but an inorganic film could also be used by similarly selecting the etching conditions for forming the grooves and the etching method used for etchback. be able to.

As shown in FIG. 4, electroplating was used as the method for forming the metal film 5, but other methods are also possible. for example,
As shown in FIG. 8, it is possible to form the conductor coil 24 by forming the metal film 5 by chemical plating.

As shown in FIG. 8(1), an insulating film 2 with grooves 2o formed therein.
An activation treatment is applied to form a chemical plating film on the entire surface of the plate. An example of this process is shown below.

S n CQ2.・2Hz0 40
g/QHCQ,
After soaking in a solution of 20 m Q / Q for 2 minutes, PdCQx 2Hz OO, 4 g / Q HCQ 4 m Q /
Pd25 is deposited on the entire surface of the insulating film 2 by immersing it in the Q solution for 2 minutes. Here, activation treatment was performed to precipitate Pd, but Au and Ag were also deposited.

Metals such as PT can be used.

By immersing the substrate that has been activated in this way in a chemical steel plating solution, it is possible to form the steel plating film 5 on the entire surface of the insulating film that has been activated. Of course, it is possible to use not only chemical steel plating but also any metal that can be chemically plated, such as gold, nickel, etc. in addition to copper.

According to this method, unlike electroplating, there is no need to form a terminal for applying electricity on the substrate, and a conductor coil can be formed on any part by performing an activation process.

In addition, as other methods, as described above, there is a method using a vacuum evaporation method or a sputtering method.

When this method is used, the unevenness on the surface of the insulating film does not become as small as in the case of the tightening method described above, so as an etch-back method, a method of flattening with an organic resin as shown in Figure 5 is recommended. It is desirable to adopt

〔Effect of the invention〕

According to the present invention, when forming high-density conductor coils of a thin-film magnetic head, by preventing air bubbles from being trapped between the coils in the insulating film, deterioration in the reliability of the magnetic head is prevented. .

Deterioration in reliability of the magnetic head can be prevented. Furthermore, since it is possible to reduce the unevenness on the surface of the insulating film formed on the coil, it is possible to prevent deterioration of the magnetic properties of the magnetic film formed thereon in the subsequent process, and also to improve the characteristics of the thin-film magnetic head. This has the effect of improving customer support and reliability.

[Brief explanation of the drawing]

FIG. 1 is a schematic process diagram showing one embodiment of the method for manufacturing a thin film magnetic head according to the present invention, and FIGS. 2 to 5 show a specific example of the method for manufacturing a thin film magnetic head according to the present invention. 6 is a graph showing the relationship between the mixing ratio of Ar-0z and the etching rate of the insulating film, and FIG. 7 is a process chart showing a specific example of the method for manufacturing a thin film magnetic head according to the present invention. . FIG. 8 is a process diagram showing another specific example. DESCRIPTION OF SYMBOLS 1... Substrate, 2... Insulating film, 3... Photoresist, 4... Plating base film, 5... Metal film.

Claims (1)

[Claims] 1. An insulating film is laminated on a substrate, and a conductor coil pattern having a pattern in which conductive corks of a predetermined shape are alternately arranged at a predetermined interval via an insulating part is formed on the insulating film. A method for manufacturing a thin film magnetic head by forming a groove in the insulating film in advance, the step of forming a groove corresponding to the shape of the conductor coil in the same pattern as the pattern, and forming a groove between the coils of the conductor coil pattern. a coil pattern forming step of forming the conductor coil pattern by filling the groove with metal that will become the conductor coil so as to insulate the conductor coil pattern; and forming a second insulating film on the insulating film having the conductor coil pattern. 1. A method of manufacturing a thin film magnetic head, comprising: a step of forming an insulating film. 2. In claim 1, a metal film serving as a conductor coil is laminated and formed in the groove in the groove pattern forming step and on the insulating film where the groove is not provided,
Next, the metal film is cut or etched to form a conductor coil pattern so that the coils of the conductor coil pattern are insulated from each other, and the groove is filled with metal that will become the conductor coil. A method of manufacturing a thin-film magnetic head, the method comprising forming a pattern. 3. In claim 1, the grooves are formed in the groove pattern forming step by forming a photoresist pattern on the insulating film, using the photoresist pattern as a mask material, and forming the grooves on the insulating film. A method for manufacturing a thin film magnetic head, characterized in that the method is performed by forming grooves.