JPH0575237A - Conductor pattern formation - Google Patents

Abstract

PURPOSE:To realize easy formation of a fine pattern regarding a formation method of a conductor pattern by a plating method which is used for formation of a coil of a thin film magnetic head, etc. CONSTITUTION:A conductor pattern formation method for forming a thin film conductor 16 of a specified pattern on an insulator 15A by a plating method. The method includes a process for providing a plating mask layer 32 whose pattern width w2 of a mask part is larger than a pattern interval (d) of the thin film conductor 16 on a plating foundation conducting film 31a which coats the insulator 15A, a first plating process for providing a plating film 33 to fill a non-masked part of the plating mask layer 32, a process for removing a part which is exposed by removal of the plating mask layer 32 inside the plating foundation conducting film 31a and a second plating process for forming the thin film conductor 16 by providing the plating film 34 to coat a surface of the plating film 33.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming a conductor pattern by a plating method and is used for forming a coil of a thin film magnetic head.

In a magnetic disk device used as an external storage device of a computer system, a small magnetic head is required to increase the recording density. Therefore, for thin-film magnetic heads, miniaturization of coil patterns is being promoted.

[0003]

2A and 2B are views showing the structure of a general thin film magnetic head 1. 2A is a cross-sectional view of the main part, and FIG. 2B is a plan view of the main part. Note that FIG. 2A corresponds to a cross section taken along the line AA of FIG.

The thin film magnetic head 1 includes a support 11 made of alumina / titanium carbide, an insulating layer 12 made of alumina, and lower and upper magnetic poles 13, 1 made of Ni--Fe.
7, a gap layer 14 made of silicon dioxide, an interlayer insulator 15 made of a thermosetting resin, a spiral coil 16 made of a Cu plating film, a protective film 18 made of alumina, and the like.

The magnetic poles 13 and 17 are integrated by a contact portion 137 to form a magnetic core. The inner end and the outer end of the coil 16 are connected to external connection terminals (not shown).

Conventionally, the coil 16 of the thin film magnetic head 1 has been formed by the following conductor pattern forming method. FIG. 3 is a cross-sectional view of an essential part showing the state of each stage of coil formation by the conventional conductor pattern forming method. In addition,
In the figure, the illustration of the non-section is omitted.

Here, already on the above-mentioned support 11,
It is assumed that the insulating layer 12, the lower magnetic pole 13, and the gap layer 14 are provided, and further that an insulator 15A that is a part of the interlayer insulator 15 (a portion below the coil 16) is provided.

First, the surface of the insulator 15A is uniformly covered by vacuum vapor deposition or sputter vapor deposition.
A base conductive film (plating base) 31a for plating having a two-layer structure, which is composed of a Ti layer having a thickness of about 0.01 μm and a Cu layer having a thickness of about 0.1 μm, is provided [FIG. 3 (a)].

Next, a photoresist solution is applied to a thickness of about 4 μm, and the coil 1 is formed by photolithography.
The plating mask layer 32 having an opening pattern (planar shape of the non-mask portion) corresponding to the pattern 6 (spiral shape) is formed [FIG. 3 (b)].

Subsequently, the film thickness is 3 μm so as to fill the non-masked portion of the plating mask layer 32 by an electrolytic plating method using the plating underlying conductive film 31a as a plating electrode.
A Cu plating film 33 of about m is formed [FIG. 3 (c)].

After removing the plating mask layer 32, the exposed portion of the plating underlying conductive film 31a is removed by ion milling, which is particularly suitable for fine processing among dry etching methods, using the Cu plating film 33 as an etching mask. [Fig. 3 (d)]. As a result, the plating underlying conductive film 31a is spirally patterned, and the Cu plating film 33 is insulated in the radial direction of the spiral to form the coil 16 [FIG. 3 (e)].

[0012]

When the pattern of the coil 16 is miniaturized in order to miniaturize the thin-film magnetic head 1, the winding width (pattern width) w of the coil 16 and the winding are inevitable. The interval (pattern interval) d is selected to be a small value. However, the film thickness of the coil 16 cannot be made thinner than a predetermined value in order to suppress an increase in resistance value.

Therefore, in the conventional forming method, after the Cu plating film 33 is formed, the plating underlying conductive film 31a is formed.
Unnecessary portions of the film, that is, the underlying conductive film 31a for plating
Patterning is performed. At this time, the Cu plating film 3
Since the underlying conductive film 31a for plating is present at the bottom of the thin and deep groove sandwiched by 3, there is a problem that patterning is difficult even if ion milling is used.

That is, high precision is required for adjusting the irradiation angle of the ions, and since the density of the ions incident on the plating base conductive film 31a is low, it takes a long time for patterning.

Since the Cu plating film 33 is used as an etching mask during ion milling,
The Cu plating film 33 is also scraped and the winding spacing d of the coil 16 is increased.
Therefore, if the width of the Cu plating film 33 is set wide in advance in consideration of this, the patterning of the plating underlying conductive film 31a becomes more difficult.

In view of the above problems, it is an object of the present invention to provide a conductor pattern forming method which can easily pattern a plating base conductive film and is suitable for miniaturization of a formation pattern.

[0017]

In order to solve the above problems, the present invention provides a conductor pattern forming method for forming a thin film conductor 16 of a predetermined pattern on an insulator 15A by a plating method as shown in FIG. And a step of providing a plating mask layer 32 having a pattern width w2 of the mask portion larger than the pattern interval d of the thin film conductors 16 on the plating underlying conductive film 31a covering the insulator 15A, and the plating mask. A first plating step of providing a plating film 33 so as to fill a non-masked portion of the layer 32, and a step of removing a portion of the plating underlying conductive film 31a exposed by the removal of the plating mask layer 32, The plating film 33
And a second plating step of forming the thin film conductor 16 by providing a plating film 34 so as to cover the surface of the.

[0018]

The pattern width w2 of the mask portion of the plating mask layer 32 is selected to be larger than the pattern distance d of the thin film conductor 16 to be formed. As a result, when patterning the underlying conductive film 31a for plating, since the region to be removed is wider than the pattern interval region of the thin film conductor 16 to be finally formed, it is easy to use an etching method such as ion milling. Can be patterned.

[0019]

EXAMPLES The method for forming a conductor pattern of the present invention will be described below by taking the formation of the coil 16 of the thin film magnetic head 1 shown in FIG. 2 as an example.

FIG. 1 is a cross-sectional view of an essential part showing the state of each stage of coil formation according to the present invention. In the figure, components having the same functions as those in FIG. 3 are designated by the same reference numerals regardless of the difference in shape and material. Further, the illustration of the non-section is omitted.

First, as in the conventional case, the underlying conductive film for plating has a two-layer structure in which a Ti layer and a Cu layer are sequentially stacked by vacuum deposition or sputter deposition so as to uniformly cover the surface of the insulator 15A. 31a (film thickness is about 0.1 μm) is provided [FIG. 1 (a)].

Next, a positive photoresist solution was added to 4 μm.
Apply to a thickness of about, and use photolithography method,
A plating mask layer 32 having an opening pattern (planar shape of the non-mask portion) corresponding to the pattern (coil shape) of the coil 16 is formed [FIG. 1 (b)].

However, the opening pattern of the plating mask layer 32 is narrower than the pattern of the coil 16. That is, the opening pattern width w1 is equal to the coil 1
6 is smaller than the pattern width w of FIG. 6, and conversely, the pattern width w2 of the mask portion of the plating mask layer 32 is the coil 1
6 is larger than the pattern interval d.

Then, in an environment in which the plating mask layer 32 made of a positive photoresist is not exposed as described above,
A Cu plating film 33 having a thickness of about several μm is formed by an electrolytic plating method using the plating underlying conductive film 31a as a plating electrode so as to fill the non-mask portion of the plating mask layer 32 [FIG. )].

Then, pattern exposure is performed on the plating mask layer 32 so as to leave a lead-out wiring pattern (not shown) for energization that is required during later plating, and a part of the plating base conductive film 31a (lead-out wiring). pattern)
After removing the plating mask layer 32 except for the upper part, the Cu plating film 33 and the remaining plating mask layer 32 are removed.
Using as an etching mask, by ion milling,
The exposed portion of the plating conductive film 31a is removed [FIG.
(D)].

At this time, the region to be removed has a width equal to the above-mentioned pattern width w2 and is wider than the pattern interval d of the thin film conductor 16, so that the pattern interval d is set to be fine for the thin film conductor 16. Even if the value is small, the width of the region to be removed as in the conventional case is the pattern spacing d of the thin film conductor 16.
Is easier to remove than when

By removing the unnecessary plating base conductive film 31a, the plating base conductive film 31a is formed into a spiral conductive film 3.
1b, the Cu plating film 33 is insulated in the radial direction of the spiral [FIG. 1 (e)].

Finally, the above-mentioned lead-out wiring pattern is connected to a power source, and the Cu plating film 3 having a predetermined thickness is coated again by electrolytic plating to cover the surface of the Cu plating film 33.
4 is provided to complete the coil 16.

[0029]

According to the present invention, it is possible to easily form a plating base conductor, which is necessary for forming a conductor pattern by a plating method, in accordance with the conductor pattern, and to miniaturize the conductor pattern. You can

[Brief description of drawings]

FIG. 1 is a sectional view of an essential part showing a state of each stage of coil formation according to the present invention.

FIG. 2 is a diagram showing a structure of a general thin film magnetic head.

FIG. 3 is a cross-sectional view of a main part showing a state of each stage of coil formation by a conventional conductor pattern forming method.

[Explanation of symbols]

 15A Insulator 16 Coil (thin film conductor) 31a Plating underlying conductive film 32 Plating mask layer 33 Cu plating film (plating film) 34 Cu plating film (plating film) w2 Pattern width d Pattern spacing

Claims (1)

[Claims] 1. A conductor pattern forming method for forming a thin film conductor (16) having a predetermined pattern on an insulator (15A) by a plating method, which comprises a base conductive film for plating (31a) covering the insulator (15A). ), A step of providing a plating mask layer (32) having a pattern width (w2) of the mask portion larger than the pattern interval (d) of the thin film conductor (16), and a non-mask of the plating mask layer (32). A first plating step of providing a plating film (33) so as to fill the portion, and a step of removing the portion of the plating underlying conductive film (31a) exposed by the removal of the plating mask layer (32); And a second step of forming a thin film conductor (16) by providing a plating film (34) so as to cover the surface of the plating film (33).
And a plating step.