JPH07121825A - Production of thin film magnetic head - Google Patents

Abstract

PURPOSE:To prevent the occurrence of wiggling at the time of reproduction in the thin film magnetic head consisting of laminated layers of a lower magnetic film, magnetic gap film, insulating layer, conductive coil film and upper magnetic film on a substrate. CONSTITUTION:A positive photoresist 20 is applied and exposed through a photomask 21 to obtain the dimension and shape of an upper magnetic film. Further, the area of the photoresist corresponding to the pole part 10 of the upper magnetic film is exposed by the degree of exposure less than that of first exposure. Then the resist is developed to pattern a resist frame 26 so that the difference of height between upper and lower surfaces of steps produced by lamination of conductive coil films is eliminated or reduced. This resist frame is used as a mask to form the upper magnetic film by electroplating. Thus, a nonhomogeneous state of the plating compsn. of the upper magnetic film can be avoided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a thin film magnetic head used in, for example, a magnetic disk device or other magnetic recording / reproducing apparatus, and more particularly to a magnetic pole portion of a lower magnetic film formed on a substrate. The present invention relates to a method for manufacturing a thin film magnetic head in which an upper magnetic film having pole portions facing each other via a gap film is patterned by electroplating using a resist frame as a mask.

[0002]

2. Description of the Related Art This type of thin film magnetic head has been widely adopted to improve the recording density as the capacity of a magnetic disk recording apparatus has been increased. It is manufactured using processing technology. For example, in the well-known in-plane recording / reproducing thin film magnetic head of FIG. 4, an insulating film 2 made of alumina or the like is deposited on a substrate 1 made of a ceramic material, and a lower magnetic film 3, a magnetic material made of alumina or the like is formed thereon. The gap film 4, the organic insulating layer 5, the conductor coil film 6, the upper magnetic film 7, and the protective film 8 such as alumina are sequentially laminated. The upper magnetic film 7 and the lower magnetic film 3 have pole portions 9 and 10 forming a pair of upper and lower magnetic poles facing each other with the magnetic gap film 4 interposed therebetween at their tips.
Behind that, there are yoke portions 11 and 12 that spread in a plane fan shape or a battledore shape, respectively, and writing / reading of information to / from the magnetic recording medium is performed at the pole portions.

Generally, when the upper magnetic film and the lower magnetic film are formed by plating, a photoresist is applied on the plating underlayer, exposed and developed using a mask and patterned, and this is used as a mask, for example, Ni-- The Fe film is patterned into a predetermined shape by a well-known process of electroplating. 5 to 7 show a process of patterning the upper magnetic film 7 by electroplating using a conventional technique.

In FIGS. 5A and 6A, a lower magnetic film 3, a magnetic gap film 4, an organic insulating layer 5, and a conductor coil film 6 are laminated on a substrate 1 whose surface is covered with an insulating film 2. On top of this, a plating base film 1 of permalloy alloy or the like
3 is formed (FIGS. 5B and 6B), a positive photoresist 14 is applied to the surface thereof (FIGS. 5C and 6C).
C). Next, as shown in FIG. 7D, a photomask 15 is placed on the photoresist 14, exposed, and developed,
A resist frame 16 defining an upper magnetic film having a predetermined shape and size is formed (FIG. 7E). Using this resist frame as a mask, for example, the NiFe film 17 is electroplated to a predetermined thickness (FIG. 7F), and the resist frame 16, the unnecessary NiFe film 17 and the plating base film 13 are removed by etching. Is obtained.

[0005]

However, in the above-described conventional method of manufacturing a thin film magnetic head, as shown in FIG. 5C, the organic insulating layer laminated in the region of the upper magnetic film 7 where the yoke portion 11 is formed is stacked. Since the layer 5 and the conductor coil film 6 form a large step between the pole portion 9 and the region where the pole portion 9 is formed, a large difference in the film thickness of the photoresist 14 occurs between the upper side and the lower side of the step. As a result, in the resist frame 16, as shown in FIG. 7E, the height h1 of the lower portion 18 of the step forming the pole portion 9 of the upper magnetic film 7 is above the step forming the yoke portion 11. It is unnecessarily higher than the height h2 of the portion 19. When a NiFe film is electroplated using this resist frame, a difference occurs in the stirring effect of the plating solution, so that the plating composition becomes non-uniform between the pole portion 9 and the yoke portion 11 of the upper magnetic film 7, and therefore the thin film is thinned. There is a problem that noise (output fluctuation) called wiggle occurs in the reproduction output of the magnetic head.

Further, in order to improve the reproduction output of the thin film magnetic head, it is necessary to increase the number of coil windings, which tends to increase the number of layers of the conductor coil. However, if the number of layers of the conductor coil is increased, the step becomes larger, and the height of the resist frame between the pole portion and the yoke portion becomes large, so that the plating composition of the upper magnetic film becomes more uneven. , There is a problem of promoting the generation of Uighur.

Further, in the magnetic recording apparatus and the like, the track width is being narrowed in order to achieve a high recording density, but for that purpose, it is necessary to reduce the pole width of the upper magnetic film. However, if the pole width is made smaller, the spacing between the resist frames on both sides of the pole becomes narrower and the height of the resist frame becomes relatively higher, so the plating composition of the upper magnetic film becomes more uneven. The problem is that

Therefore, the method of manufacturing the thin film magnetic head according to the first aspect is made in view of the above-mentioned conventional problems, and the purpose thereof is to provide a lower magnetic film and a magnetic gap film on the substrate. , An insulating layer, and a conductor coil film are laminated, a resist frame is patterned with a photoresist on this, and the upper magnetic film is patterned by electroplating using this as a mask. By a relatively simple method without increasing significantly, the yoke portion of the upper magnetic film formed above the step and the pole portion of the upper magnetic film formed below the step caused by the lamination of the conductor coils By eliminating non-uniformity of the plating composition between the two, it prevents the generation of wiggle during regeneration, which makes it possible to increase the number of coil turns. Is to provide a method for producing a playback output improvement can be achieved in, and then allow the narrow track can achieve high recording density thin film magnetic head.

[0009]

The present invention is to achieve the above-mentioned object, and the contents thereof will be described below with reference to the embodiments shown in the drawings.

According to a first aspect of the present invention, there is provided a method for manufacturing a thin film magnetic head, in which a lower magnetic film having a pole portion, a magnetic gap film, an insulating layer and a conductor coil film are laminated on a substrate, and a positive type photoresist is formed thereon. The resist frame is patterned, and electroplating is performed using this as a mask to form an upper magnetic film having a pole portion opposed to the pole portion of the lower magnetic film through the magnetic gap film. The step of exposing the photoresist in the resist frame portion forming the pole portion to partially remove the photoresist in the resist frame portion in the film thickness direction.

[0011]

Therefore, according to the method of manufacturing the thin film magnetic head of the first aspect, when the upper magnetic film is patterned to be continuous with the lower side and the upper side of the step formed by stacking the conductor coil films, The height of the resist frame portion that defines the pole portion of the upper magnetic film can be appropriately adjusted to be low. This makes it possible to eliminate or reduce the difference in height of the resist frame between the lower side and the upper side of the step. It can be adjusted so that there is no difference in the stirring effect.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of the method of manufacturing a thin film magnetic head according to the present invention will be described in detail below with reference to FIGS.

Similar to the conventional manufacturing method described with reference to FIGS. 5 and 6, a substrate 1 made of an Al ₂ O ₃ —TiC-based ceramic material has a lower magnetic layer on an insulating film 2 such as alumina. The film 3 is patterned into a predetermined size and shape by sputtering or electroplating, for example, permalloy alloy, sendust, amorphous alloy or the like, on which a magnetic gap film 4 such as alumina and an insulating layer such as novolac resin are formed. 5 and a conductor coil 6 made of Cu are laminated by using a photolithography technique. As described above, the lower magnetic film 3 includes the pole portion 10 at the tip of the head and the yoke portion 1 that extends behind the pole portion 10 in a fan shape or a battledore shape.
2 and a large step is formed on the substrate by the two-layer conductor coil 6 which is laminated in the region including the yoke portion with the insulating layer 5 interposed therebetween. A pole portion of the upper magnetic film facing the pole portion 10 of the lower magnetic film 3 via the magnetic gap film 4 is formed below the step, and on the upper side of the step continuously from the pole portion, The yoke portion of the upper magnetic film is formed so as to be magnetically coupled to the yoke portion 12 of the lower magnetic film 3 at the rear position.

The plating base film 13 is formed on the entire substrate by, for example, sputtering a permalloy alloy.
Thin film is coated, and positive type photoresist 2 is formed on it.
0 is applied relatively thickly. According to the present invention, first, as shown in FIG. 1, a photomask 21 is arranged above the substrate thus coated with the photoresist 20. Similar to the photomask 15 of FIG. 7D, the photomask 21 is provided with a window 22 that conforms to the size and shape of the upper magnetic film to be formed. By exposing the photoresist 20 using this photomask, the photoresist other than the portion 23 serving as the resist frame that defines the upper magnetic film corresponding to the resist frame 16 shown in FIG. 7E is exposed.

Next, as shown in FIG. 2, another photomask 24 is placed above the photoresist 20. A window 25 is provided in the photomask 24 so as to expose a region of the photoresist 20 corresponding to a portion of the resist frame defining the pole portion of the upper magnetic film, that is, a region below the step. There is. The photoresist 20 is exposed again using this photomask. At this time, the second
The exposure amount for the first exposure is set to be smaller than the exposure amount for the first exposure at which the photoresist is completely removed when developed later. Therefore, the photoresist 20 in the second exposed area
Is partially exposed in the film thickness direction from its surface. The photoresist 20 is then developed to remove the exposed portions of the second exposure in addition to the exposed portions of the first exposure, as shown in FIGS. 3A and 3B.
It is possible to obtain the resist frame 26 in which the lower part of the step is lower than the conventional one.

By properly adjusting the exposure amount of the second photoresist, the resist frame portion 2 defining the lower portion of the step, that is, the pole portion of the upper magnetic film.
The height of 7 can be adjusted. In this embodiment, FIG.
When the second exposure was performed with an exposure amount of about 50% of the first exposure in the above, the height H1 of the resist frame portion 27 was lowered to about half of the conventional height h1 (FIG. 7E). Therefore, the difference from the height H2 of the resist frame portion 28 defining the yoke portion of the upper magnetic film above the step, that is, the difference can be significantly reduced. By electroplating a soft magnetic material such as a known permalloy alloy, for example, a NiFe film using the resist frame 26 as a mask, an upper magnetic film having no difference in plating composition between the pole portion and the yoke portion was obtained.

In another embodiment, the photoresist 20 can be exposed first using the photomask 24 of FIG. 2 and then exposed by the photomask 21. In this case as well, it is possible to obtain a resist frame in which the height of the portion defining the pole portion of the upper magnetic film is similarly reduced.
Further, the exposure range of the photoresist by the photomask 24 in FIG. 2 may vary depending on manufacturing conditions and various other conditions.
The resist frame portion defining the pole portion of the upper magnetic film may be the whole or a part thereof. Further, as will be apparent to those skilled in the art, the present invention can be carried out by making various modifications and variations to the above-described embodiments within the technical scope thereof.

[0018]

Since the present invention is constituted as described above, it has the following effects.

According to the method of manufacturing the thin film magnetic head of the first aspect, despite the step difference due to the lamination of the conductor coil films,
The height of the resist frame portion formed below the step is adjusted to be appropriately low by using a relatively simple and low-cost method, and the height of the resist frame above and below the step is adjusted appropriately. Since it is possible to eliminate or reduce the difference in thickness, it is possible to eliminate the unevenness of the plating composition between the pole part and the yoke part of the upper magnetic film, and effectively prevent the generation of wiggle during reproduction. To be done. Therefore, it is possible to realize a high reproduction output by increasing the number of coil turns, and it is possible to easily achieve a high recording density even if the pole width is reduced by narrowing the track.

[Brief description of drawings]

FIG. 1 is a cross-sectional view seen from the recording medium side showing a process of exposing a photoresist to form a resist frame of an upper magnetic film by the manufacturing method of the present invention.

FIG. 2 is a cross-sectional view showing a process of further exposing the photoresist of FIG.

3A and 3B are sectional views of a patterned resist frame as seen from the recording medium side, and FIG.
The drawing is a vertical sectional view of FIG.

FIG. 4 is a longitudinal sectional view showing a main part of a conventional thin film magnetic head.

5A to 5C are longitudinal sectional views showing the first half of the step of forming the resist frame of the upper magnetic film by the conventional manufacturing method, which is shown in FIGS.

FIG. 6 is a view from the recording medium side corresponding to each process of FIG.
It is sectional drawing which consists of FIGS.

7 is a sectional view similar to FIG. 6 showing the second half of the steps of FIGS. 5 and 6 and including D to F views.

[Explanation of symbols]

 1 Substrate 2 Insulating Film 3 Lower Magnetic Film 4 Magnetic Gap Film 5 Organic Insulating Layer 6 Conductor Coil Film 7 Upper Magnetic Film 8 Protective Film 9, 10 Pole Part 11, 12 Yoke Part 13 Plating Base Film 14 Photoresist 15 Photomask 16 Resist Frame 17 NiFe film 18 Lower part 19 Upper part 20 Photoresist 21 Photomask 22 Window 23 part 24 Photomask 25 Window 26 Resist frame 27, 28 Resist frame part

Claims (1)

[Claims] 1. A lower magnetic film having a pole portion, a magnetic gap film, an insulating layer and a conductor coil film are laminated on a substrate, and a resist frame made of a positive photoresist is patterned on the laminated film, which is used as a mask. A method of manufacturing a thin-film magnetic head, comprising forming an upper magnetic film having a pole portion opposed to a pole portion of the lower magnetic film through the magnetic gap film by electroplating, the pole portion of the upper magnetic film. A method of manufacturing a thin-film magnetic head, comprising the step of exposing the photoresist in the portion of the resist frame forming the film to partially remove the photoresist in the resist frame portion in the film thickness direction.