JPH07153027A - Thin film magnetic head and its manufacture - Google Patents

Abstract

PURPOSE:To obtain a thin film magnetic head which has high quality and high reliability and in which metallic corrosion, etc., is not produced from the surrounding of a metal terminal even if the thickness of the metal terminal is large, and provide a thin film magnetic head whose thick film metal terminal can be formed in a short time and which can be manufactured at a low cost with high productivity. CONSTITUTION:A resist film 12 is built up on a leader terminal 2 to form the thick film part of a metal terminal and a foundation electrode film 3 for the plating of the metal terminal is built up on the resist film 12. Then a plating film is applied to the foundation electrode film 3 for the plating of the metal terminal to provide, for instance, a copper terminal 10.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thin film magnetic head used in a hard disk drive capable of ultra high density recording and a method for manufacturing the same.

[0002]

2. Description of the Related Art In recent years, in thin film magnetic heads, the lamination of coil layers constituting the magnetic head element portion has progressed, and for this reason, it is necessary to increase the thickness of metal terminals such as gold, platinum, silver and copper. Therefore, various metal terminal forming methods have been developed.

Conventionally, the metal terminal forming process of a thin film magnetic head has generally been a method of selectively forming a film by plating on a portion not covered with a resist film by an electrolytic plating method. However, there is a limit to the resist film thickness. For example, in copper terminal plating that exceeds the resist film thickness, the copper terminal is formed overhanging beyond the resist film thickness. When the protective film is formed by sputtering, the coverage of the sputtering film is poor, and after flattening the protective film, a groove is created in the area around the copper terminal where the sputtering film is uneven. However, there is a problem that metal corrosion easily occurs around the copper terminals and durability and reliability are poor.

Therefore, in order to solve the above problems, after metal terminal plating is performed to a film thickness approximately the same as the resist film thickness,
There is known a metal terminal forming method in which a metal terminal pattern having a larger area than that of the metal terminal is overlapped and formed on the metal terminal to form a metal terminal thicker than the resist film thickness.

A conventional thin film magnetic head will be described below. FIG. 5 is a cross-sectional view of an essential part of a copper terminal portion of a conventional thin film magnetic head. Reference numeral 1 is a substrate on which a magnetic head element portion (not shown) is formed, 2 is a lead terminal which is electrically connected to the magnetic head element portion laminated on the substrate 1, 3 is a base electrode film for metal terminal plating, and 7 is electrolytic plating Inner copper terminal formed by the method, 9 is a large area outer copper terminal formed by electrolytic plating on the inner copper terminal 7, and 10 is a thick wall formed by laminating the outer copper terminal 9 on the inner copper terminal 7. The formed copper terminal 11 is an alumina protective film obtained by laminating a protective film flattened on the alumina protective film formed by sputtering on the external copper terminal 9.

A method of manufacturing the thin film magnetic head having the above structure will be described below. 6 (a) to 8 (c) are cross-sectional views of a main part showing a step of forming a copper terminal of a conventional thin film magnetic head. Reference numeral 4 denotes a resist film for temporarily forming the internal copper terminal pattern 5 to form the internal copper terminal 7, and 6 denotes temporarily forming the external copper terminal pattern 8 to form the external copper terminal 9. Of the resist film. First, as shown in FIG. 6A, a metal terminal plating base electrode film 3 is sputter-deposited on the surface of the lead terminal 2 which is electrically connected to the magnetic head element portion formed on the substrate 1. Next, a positive type resist film 4 is coated on the base electrode film 3 for metal terminal plating, and after a predetermined heat treatment is applied,
After exposure and development, washing with pure water is performed to form an internal copper terminal pattern 5 as shown in FIG. 6 (b). Subsequently, an external copper terminal pattern 8 for forming an external copper terminal 9 having a larger area than the internal copper terminal pattern 5 is provided so that the internal copper terminal pattern 5 is located in the center of the external copper terminal pattern 8. Only the exposure is performed for the part of. Then, an internal copper terminal 7 is formed on the exposed portion of the internal copper terminal pattern 5 of the metal terminal plating base electrode film 3 by electrolytic plating as shown in FIG. 6C. Next, after developing the exposed resist film 6 in the previous step, washing with pure water is performed to expose the base electrode film 3 for metal terminal plating and the internal copper terminals 7 to expose the external copper as shown in FIG. 7A. The terminal pattern 8 is formed. Next, the external copper terminals 9 are formed on the exposed plating film surfaces of the metal terminal plating base electrode film 3 and the internal copper terminals 7 by electrolytic plating. At this time, since the film thickness of the external copper terminal 9 is thinner than the film thickness of the resist film 4, it does not overhang the resist film 4 to overhang. Also, the internal copper terminal 7
In the above, the film thicknesses of the external copper terminals 9 are overlapped,
As shown in FIG. 7B, a copper terminal thicker than the resist film 4 can be plated. Next, as shown in FIG. 7C, after the resist film 4 is removed by whole surface exposure, unnecessary portions of the metal terminal plating base electrode film 3 exposed by chemical etching are removed, and as shown in FIG. As shown in a), a copper terminal 10 is formed which is composed of a substantially trapezoidal inner copper terminal 7 and an outer copper terminal 9. Next, as shown in FIG. 8B, an alumina protective film 11 is formed by sputtering. At this time, copper terminal 1
Since 0 has a substantially trapezoidal shape, the coverage of sputter film formation is improved, and no cavity is formed around the copper terminal 10. Next, as shown in FIG. 8C, a protective film flattening lapping process is performed to expose the external copper terminals 9 to form the copper terminals 10.

[0007]

However, in the above conventional structure, the internal copper terminal and the external copper terminal are formed by the electrolytic plating method, and for example, the copper terminal having a film thickness of 60 microns is formed on the 3-inch substrate. Case cathode current density 4A / dm
^{In the case of 2,} it took 60 minutes per substrate, and the plating process took a long time. The normal proper cathode current density is 5
In the range of ^{A / dm 2 ~1A / dm 2} , there is a limit in shortening the plating time by flowing a large current, there is a problem of lack in productivity. Further, in the electrolytic plating method, there is a problem in that it is necessary to increase the number of plating tanks in order to increase the productivity for single-wafer processing, which requires equipment costs such as a power source.

The present invention solves the above-mentioned problems of the prior art by providing a high quality and highly reliable thin film magnetic head in which metal corrosion does not occur around the metal terminals even if the film thickness of the metal terminals is increased. Another object of the present invention is to provide a method of manufacturing a thin film magnetic head which can form a metal terminal having a large film thickness in a short time and is excellent in productivity at low cost.

[0009]

To achieve this object, a thin film magnetic head according to claim 1 of the present invention comprises a resist film forming a thick portion of a metal terminal laminated on a lead terminal. A metal terminal-plating base electrode film deposited and laminated on the resist film, and a metal terminal plated on the metal terminal-plating base electrode film. Item 2. The method of manufacturing a thin-film magnetic head according to Item 2, which is a method of manufacturing a thin-film magnetic head having a metal terminal, including a resist film forming step of forming a resist film forming a thick portion of the metal terminal, and the resist. A metal terminal plating base electrode film forming step of depositing and laminating a metal terminal plating base electrode film on the film; and a metal terminal forming step of plating and forming a metal terminal on the metal terminal plating base electrode film. Prepared configuration It has.

Copper terminals are generally used as metal terminals, but gold terminals, silver terminals, platinum terminals and the like may be used. By stacking and covering the metal film so that the metal terminal encloses the terminal-shaped resist film, a thick metal terminal integrated with the resist film can be formed.
Further, the resist film for forming the thick portion of the metal terminal may be formed independently at the time of forming the metal terminal, but it may be stacked stepwise when forming the resist film insulating layer forming the magnetic head element portion. You may form. This can further shorten the copper terminal formation time.

[0011]

With this structure, the thick portion of the metal terminal is formed of the resist film, and the metal plating film is laminated and covered so as to wrap the resist film to form the metal terminal. A thick metal terminal can be formed in a short time.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS 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 sectional view of an essential part of a copper terminal portion of a thin film magnetic head according to an embodiment of the present invention. Reference numeral 1 is a substrate, 2 is a lead terminal, 3 is a base electrode film for plating a metal terminal, 9 is an external copper terminal, 10 is a copper terminal, and 11 is an alumina protective film. Is attached and the description is omitted. 1
2 is a resist film in the shape of an internal copper terminal.

A method of manufacturing the thin film magnetic head having the above structure according to the embodiment of the present invention will be described below. 2 (a) to 4 (c) are cross-sectional views of essential parts showing a copper terminal forming step of the thin film magnetic head in one embodiment of the present invention. Reference numeral 4 is a resist film, and 8 is an external copper terminal pattern, which is the same as that of the conventional example and is given the same reference numeral and its description is omitted. First, as shown in FIG. 2A, a novolac-based positive type resist film is formed on the surface of the lead terminal 2 which is electrically connected to the formed magnetic head element portion on the substrate 1 on which the magnetic head element portion (not shown) is formed. 12 to 40
After spin coating with a spinner so that it becomes micron,
Heat treatment is performed in an oven at 90 ° C. for 30 minutes. Next, after exposing and developing this resist film 12, it is washed with pure water to obtain the structure shown in FIG.
A resist film 12 having the shape of the internal copper terminal 7 as shown in (b) is formed. The size of this resist film 12 is 12
The rectangular cross section of 0 micron × 180 micron has a film thickness of 40 micron. Next, this resist film 12 is heat-treated in an oven at 140 ° C. × 30 minutes and 170 ° C. × 120 minutes to sinter the resist film 12. Next, as shown in FIG. 2C, a metal terminal plating base electrode film 3 is laminated and covered by sputtering to a thickness of 1000 Å so as to surround the lead terminals 2 and the resist film 12.

Next, as shown in FIG. 3 (a), a novolac-based positive type resist film 4 is spin-coated by a spinner so that the film thickness becomes 40 microns, and the resist film 4 is heated in an oven 9
After heat treatment at 0 ° C. for 30 minutes, the resist film 12 having the shape of the internal copper terminal 7 is exposed and developed so as to be located at the center of the external copper terminal pattern 8, and then washed with pure water to form the external copper terminal pattern 8. Form. Next, as shown in FIG. 3B, external copper terminals 9 are formed on the exposed portions of the metal terminal plating base electrode film 3 by electrolytic plating. The external copper terminal 9 has a rectangular cross section of 200 μm × 260 μm and a film thickness of 20 μm. The conditions for electrolytic plating are cathode current density of 4 A / dm ² and 20 minutes per substrate. At this time, since the film thickness of the external copper terminal 9 is smaller than the film thickness of the resist film 4, it does not get over the resist film 4. On the resist film 12 in the shape of the internal copper terminal 7, the film thickness of the external copper terminal 9 is added, and the film thickness 60 is larger than that of the resist film 4.
Thus, the micron copper terminal 10 is formed. next,
As shown in FIG. 3C, the resist film 4 is entirely exposed and developed, and then washed with pure water to remove the resist film 4.

Next, the base electrode film 3 for metal terminal plating is chemically etched by a copper etching solution in which ammonium persulfate 30 g / l, sodium lauryl sulfate 0.05 g / l and sodium hydroxide are adjusted to pH 6 to 7. The unnecessary portion is removed to form a copper terminal 10 having a film thickness of 60 μm, which is composed of the resist film 12 and the external copper terminal 9 having a substantially trapezoidal shape as shown in FIG.

Next, as shown in FIG. 4B, an alumina protective film 11 is formed on the copper terminal 10 by sputtering,
As shown in FIG. 4C, a protective film flattening lapping process is performed to expose the external copper terminals 9 to form the copper terminals 10.

In this embodiment, it is necessary to newly form a resist film having the shape of the internal copper terminal and to perform heat treatment, but the time required for forming the resist film is as short as about 5 minutes, and Since the heat treatment of the resist film can be performed on a plurality of sheets at the same time, the copper terminal formation time can be shortened by about 40% compared with the conventional case. Further, when forming a resist film insulating layer (not shown) forming the magnetic head element portion, a heat treatment is performed in which resist films having the shape of internal copper terminals are stacked in stages and the resist film insulating layer is baked and solidified. By utilizing the heat treatment of the resist film having the internal copper terminal shape, the copper terminal forming time could be shortened by about 60% as compared with the conventional case. Furthermore, since the number of plating tanks is small, the cost of power supply equipment can be reduced by about 30%.

As described above, according to the present embodiment, the thick portion of the copper terminal is formed of the resist film, and after being baked and hardened, the copper terminal is electrolytically plated on the resist film so as to wrap the resist film. This makes it possible to form a substantially thick copper terminal in a short time.

[0019]

As described above, according to the present invention, the metal terminal is formed by forming the thick portion of the metal terminal with the resist film and laminating and covering the metal plating film so as to surround the resist film. In addition, it is possible to increase the film thickness of the metal terminal and realize a high quality and highly reliable thin film magnetic head in which metal corrosion does not occur around the metal terminal. It is possible to realize a method for manufacturing a thin film magnetic head that can be formed, is low in cost, and has excellent productivity.

[Brief description of drawings]

FIG. 1 is a sectional view of an essential part of a copper terminal portion of a thin film magnetic head according to an embodiment of the present invention.

FIG. 2A is a sectional view of a main part showing a copper terminal forming step of a thin film magnetic head according to an embodiment of the present invention. FIG. 2B shows a copper terminal forming step of a thin film magnetic head according to an embodiment of the present invention. Sectional view of essential part (c) is a sectional view of essential part showing a step of forming a copper terminal of a thin-film magnetic head according to an embodiment of the present invention.

FIG. 3A is a sectional view of a principal part showing a copper terminal forming process of a thin film magnetic head according to an embodiment of the present invention. FIG. 3B is a copper terminal forming process of a thin film magnetic head according to an embodiment of the present invention. Sectional view of essential part (c) is a sectional view of essential part showing a step of forming a copper terminal of a thin-film magnetic head according to an embodiment of the present invention.

FIG. 4A is a sectional view of a principal part showing a copper terminal forming step of a thin film magnetic head according to an embodiment of the present invention, and FIG. 4B is a copper terminal forming step of a thin film magnetic head according to an embodiment of the present invention. Sectional view of essential part (c) is a sectional view of essential part showing a step of forming a copper terminal of a thin-film magnetic head according to an embodiment of the present invention.

FIG. 5 is a cross-sectional view of essential parts of a copper terminal portion of a conventional thin film magnetic head.

FIG. 6A is a sectional view of a main part showing a copper terminal forming process of a conventional thin film magnetic head, and FIG. 6B is a sectional view of a main part showing a copper terminal forming process of a conventional thin film magnetic head. Sectional drawing of the principal part which shows the copper terminal formation process of a thin film magnetic head.

7A is a cross-sectional view of a main part showing a copper terminal forming process of a conventional thin film magnetic head, FIG. 7B is a cross-sectional view of a main part showing a copper terminal forming process of a conventional thin film magnetic head, and FIG. Sectional drawing of the principal part which shows the copper terminal formation process of a thin film magnetic head.

FIG. 8A is a sectional view of a main part showing a copper terminal forming process of a conventional thin film magnetic head, and FIG. 8B is a sectional view of a main part showing a copper terminal forming process of a conventional thin film magnetic head. Sectional drawing of the principal part which shows the copper terminal formation process of a thin film magnetic head.

[Explanation of symbols]

 1 substrate 2 lead terminal 3 base electrode film for metal terminal plating 4, 6, 12 resist film 5 internal copper terminal pattern 7 internal copper terminal 8 external copper terminal pattern 9 external copper terminal 10 copper terminal 11 alumina protective film

Claims (2)

[Claims] 1. A resist film constituting a thick portion of a metal terminal laminated on a lead terminal, a metal terminal plating base electrode film laminated and covered on the resist film, and the metal terminal plating. A thin-film magnetic head, comprising: a metal terminal plated on the underlying electrode film. 2. A method of manufacturing a thin film magnetic head having metal terminals, comprising: a resist film forming step of forming a resist film forming a thick portion of the metal terminal; and a metal terminal plating base on the resist film. A thin film comprising: a step of forming a base electrode film for metal terminal plating for depositing and laminating an electrode film; and a step of forming a metal terminal by plating a metal terminal on the base electrode film for metal terminal plating. Magnetic head manufacturing method.