JPH0323508A - Production of thin-film magnetic head - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method for manufacturing a thin film magnetic head used in a magnetic recording/reproducing device that reads data from or writes data to a magnetic recording medium. It is.

Conventional technology FIG. 4 is a sectional view showing a conventional thin film magnetic head, in which 1 is a substrate made of a non-magnetic material, 2 is an insulating layer, and the insulating layer 2 is formed on the substrate 1, and is made of alumina, etc. It is formed of.

3 is a lower magnetic layer, the lower magnetic layer 3 is formed on the insulating layer 2, and is made of Ni-Fe. It is secured with magnetic material. The lower magnetic layer 3 is composed of a magnetic film 3a and a magnetic film 3b formed on the magnetic film 3a. 4 is a gap layer, and the gap layer 4 is formed on the lower magnetic layer 3. 5 is an insulating layer, and the insulation layer is made of alumina.
is formed on the gap layer 4 and is made of photoresist or the like. 6 is a coil layer, and coil layer 6 is an insulation M5
It is made of a good conductor such as copper. Further, the coil layer 6 is provided with a lead-out portion 6a. Reference numeral 7 denotes an insulating layer, and the insulating layer 7 is formed on the insulating layer 5 so as to cover the coil layer 6, and is made of photoresist or the like.

Further, a part of the extended portion 6a is covered with an insulating layer 7. Reference numeral 8 denotes an upper magnetic layer, and the upper magnetic layer 8 is provided on the top 8M7 so as to constitute a magnetic circuit together with the lower magnetic layer 3. Further, the upper magnetic layer 8 is made of Ni--Fe magnetic material. When creating the upper magnetic layer 8, the magnetic film 8a is first formed, and then the magnetic film 8b is formed thereon. The lead 9 is made of the same material as the upper magnetic layer 8 and formed in the same process as the upper magnetic layer 8.

The lead 9 is connected to the lead-out portion 6a. Here, we will explain why the lead 9 is formed from NIFe magnetic material instead of using steel as the lead material. Generally, a thin copper film is not bonded to a non-magnetic material such as a ceramic used as an insulating layer or a substrate, and it easily peels off from the insulating layer, making it unsuitable for use as a lead formed on the insulating layer 2. It is. However, a metal magnetic film such as Ni-Fe has relatively good compatibility with an insulating film and is firmly bonded to the insulating film. MataNi-
Since the Fe magnetic material has low electrical resistance, it is suitable as a lead formed on the substrate 1. 10 is the terminal part,
The terminal portion 10 is connected to the lead 9 and is made of steel. The terminal portion 10 is formed by first forming a base layer 10a on the lead 9 by sputtering, and then plating the base layer 10a with M sulfuric acid plating. The reason for forming the base layer 10a is as follows. In general, when copper plating is applied to an alloy containing a metal that has a greater ionization tendency than copper, such as an alloy containing Fe, a copper mirror gold layer is not formed by the copper sulfate plating solution. This is because it will peel off quickly. Therefore, first, a copper base layer 10a is formed by sputtering, and then copper plating is applied thereon by copper sulfate plating to form the terminal portion 10. A conductive wire 11 is bonded to the terminal portion]0 using a wire bonder or the like. 12 is a protective layer made of alumina or the like.

In the conventional thin film magnetic head configured as described above,
A method of manufacturing the terminal portion 10 will be explained.

First, the -E section magnetic layer 8 and the leads 9 are formed, and as shown in FIG.
Apply 4. Next, as shown in FIG. 6, a portion of the photo resist 14 on the lead 9 is irradiated with ultraviolet rays, and the irradiated portion is washed away with a developer to form a recess 14a.

Next, the outer periphery of the half head is sandwiched between plating frames (not shown). Then, the outer periphery of the plating frame and half of the head is exposed! @The end surfaces of the thin film 13 are in contact with each other. In this state, the head half is immersed together with the plating frame in a copper sulfate plating solution. Then, when the plating layer is energized, the plating film is laminated on the exposed portion of the recess 14a of the steel sheet 113, and the terminal portion 10 is formed as shown in FIG. Next, the entire surface is irradiated with ultraviolet rays, and then the photoresist 14 is completely removed using a developer. Thereafter, as shown in FIG. 8, all exposed portions of the copper thin film 13 are removed by ion milling. Finally, a protective layer 12 is formed.

Problems to be Solved by the Invention However, in the conventional method, the steel thin film [13] is removed after forming the terminal portion 10, but at this time, as shown in FIG. There remains a steel thin film A that cannot be removed by ion milling, and the remaining copper thin film A is exposed on the medium facing surface.
This caused the lower magnetic layer 3 to corrode over time. Further, even if it is not exposed to face the medium, the difference in ionization tendency between copper and Fe in the lower magnetic M3 causes a battery action, resulting in a problem that the magnetic properties of the lower iaffJl3 deteriorate. To solve this problem, the first step is to
As shown in Figure 0, the upper magnetic field 1f1-. A possible method is to form a 7 photoresist film 15 on the M8 and -1 magnetic layers 3, and then to form a copper thin film 13 by sputtering to form the base film 10a. 7, a developing process and an exposure process for the photoresist 15 must be performed, resulting in an increase in the number of processes and a problem of poor productivity.

The present invention aims to solve the above-mentioned conventional problems,
The purpose of the present invention is to provide a method for manufacturing a thin-film magnetic head that does not require the formation of a sputtered copper underlayer when forming a terminal portion, thereby reducing manufacturing steps and preventing corrosion of the lower magnetic layer.

Means for Solving the Problems In order to achieve this object, the leads were immersed in a birophosphate steel plating solution to form a plating layer on the leads that would become the terminal portion.

Function: With this method, it is possible to form a plating layer that will become a terminal portion on the lead by direct plating, and the terminal portion is resistant to peeling.

Embodiment FIG. 1 is a sectional view showing a thin film magnetic head manufactured by a method for manufacturing a thin film magnetic head according to an embodiment of the present invention. l is the substrate, 2 is the insulating layer, 3 is the lower magnetic layer, 3
a is a magnetic film, 3b is a magnetic film, 4 is a gap layer, 5 is an insulating layer, 6 is a coil layer, 62N is a lead-out portion, 7 is an insulation counterfeit, 8
8a is an upper magnetic layer, 8a is a magnetic film, 8b is a magnetic film, 9 is a lead, 1l is a winding wire, and 12 is a protective layer, which are the same as the conventional structure. 17 is a terminal portion, and the terminal portion 17 is formed on the lead 9 by plating using birophosphate steel plating solution. The birophosphate fIA plating solution is composed of 57 g of copper birophosphate, 250 g of calcium birophosphate, 3 cc of ammonia, and Log of calcicum nitrate dissolved in 1 liter of water. It can also be obtained by mixing calcium oxalate or other brighteners as an antifoaming agent, if necessary.

Below, R u'! in one embodiment of the present invention! A method of manufacturing a magnetic head will be explained. First, as shown in FIG. 2, the photoresist film 18 is attached to the lead 10. The photoresist film 18 of the portion 2L where the terminal portion 17 of the lead 9 is to be formed is irradiated with ultraviolet rays, and that portion is washed away with a developer to form the recess 19 that reaches the first portion 9. Cheating. Step 1: The substrate 1 is immersed in birophosphate plating solution so that the recess 19 is immersed in the birophosphate plating solution as shown in step 31A, and plating is performed to form the terminal portion 17 having a thickness of 55 μm.

At this time, the temperature of the birophosphate plating solution is set to 55°C, and the pH value of the birophosphate plating solution is set to 8.5 to 8.5 to prevent the photoresist film 18 from rising and being attacked by the birophosphate plating solution.
Set it to 7.0. Plating with biU phosphoric acid fli4m gold solution has a much stronger bonding force with the lead 9 than conventional sulfuric acid M plating. Therefore, no base film is required. Also, cyanide as a plating solution that does not require such a base film! Examples include @plating solution and fluoroborated steel plating solution, but these are highly toxic and undesirable. Next, the entire surface is irradiated with ultraviolet rays, and all of the photoresist III 18 is washed away by a developer. Finally lol! ! A rim layer l2 is formed.

1'1, the corrosion resistance of thin film magnetic heads formed by the conventional manufacturing method and the manufacturing method of this embodiment was compared. It was created using the conventional manufacturing method and the manufacturing method of this example. i'N film magnetic head at humidity 8
The sample was left for 24 hours in an atmosphere with a 5% temperature of 85°C. As a result, thin film magnetic heads produced using conventional manufacturing methods suffered from corrosion on the side facing the medium. However, no corrosion occurred in the thin film magnetic head manufactured by the manufacturing method of this example.

As described below, according to this embodiment, since the terminal portion 17 is formed using birophosphate copper plating solution, there is no need to form a base film, which reduces the number of manufacturing steps compared to the conventional method, and reduces the number of lower parts. No copper thin film remains at the boundary between the magnetic layer 3 and the insulating layer 2, and corrosion of the lower magnetic layer 3 does not occur.

In addition, 1 μm Pl.
Alternatively, a terminal portion may be formed by forming a base film to a thickness of about 100 mL, and then plating the base film with M sulfuric acid.

Effects of the Invention In the present invention, the terminal portion is formed on the lead by immersing the lead in a birophosphate copper plating solution, so that the terminal portion is difficult to peel off. Since the plating layer that will become the lead I- (one terminal part) can be formed by direct plating without the need for direct plating, the number of steps is reduced compared to the conventional process of creating a base film by sputtering.
In addition to improving productivity, it is possible to prevent deterioration of the lower magnetic layer due to residual steel.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing a thin film magnetic head manufactured by a manufacturing method according to an embodiment of the present invention, FIGS. 2 and 3 are sectional views showing a method for manufacturing a terminal portion, and FIG. 5 to 8 are cross-sectional views showing a method for manufacturing the terminal portion of a conventional thin-film magnetic head. FIG. 9 is a cross-sectional view showing a method for manufacturing a conventional thin-film magnetic head. FIG. 10 is a longitudinal cross-sectional view of the head and is a cross-sectional view showing another conventional method of manufacturing a thin film magnetic head. 1 2 1 7 1 8 1 9 Protective layer Terminal photoresist film Recess substrate Insulating layer Lower magnetic layer Magnetic film Magnetic film Gap layer Insulating layer Coil layer Leading portion Insulating layer Upper magnetic layer Magnetic film Magnetic film Lead winding

Claims (1)

[Claims] A lower magnetic layer is formed on the substrate, a gap layer is formed on the lower magnetic layer, a coil layer having a lead-out portion is formed on the lower magnetic layer, and an upper magnetic layer is formed on the coil layer. A plating layer that will become a terminal portion is formed on the lead by forming a lead that connects to the lead-out portion on the substrate and immersing the lead in a copper pyrophosphate plating solution. A method for manufacturing a thin film magnetic head.