JPS6284519A - Forming method for mask for ion etching - Google Patents

Abstract

PURPOSE:To obtain a metal film mask for ion etching which ensures an excellent pattern precision, by a method wherein a moderately-sloping layer for sloping a stepped portion moderately is applied by coating on a thin film layer in which the stepped portion is formed by the indented surface of a lower pattern layer. CONSTITUTION:An insulating layer 34 is provided on a first conductor pattern layer 33 which is patterned on a substrate 31 with an insulating layer 34 interposed between them, and a conductor layer 36 is connected thereon. After a moderately-sloping layer 37 forming of a resin material and provided for sloping a stepped portion moderately is applied by coating on the conductor layer 36 in which the stepped portion is formed by the indented surface of the pattern layer 33, a metal film 38 is connected thereon. The metal film 38 is patterned with a resist pattern 39 used as a mask. In succession, the moderately-sloping layer 37 except for the part thereof in a region wherein the patterned metal film is formed is removed selectively by etching, and a metal film mask 40 for ion etching is formed on the conductor layer 36. The conductor layer 36 is ion-etched with the mask 40 being used, and thereby a section conductor pattern layer 41 can be obtained with excellent precision.

Description

[Detailed Description of the Invention] [Summary] The present invention involves applying a relaxation layer made of a resin material to alleviate the level difference on a thin film layer that has a level difference due to the uneven surface of the lower pattern layer. A mask pattern for patterning the thin film layer is deposited and formed, and a metal film mask for ion etching with good pattern accuracy without side etch defects can be easily formed at the step portion.

[Industrial application field]

The present invention relates to a method for forming a metal film mask for ion etching, and more particularly to an improvement in a method for forming a metal film mask that allows a thin film layer having steps to be patterned with high precision by ion etching.

When forming a helical multilayer thin film coil in the manufacture of an inductive thin film magnetic head, the conductor layer formed on the first coil pattern layer with an insulating layer interposed is
The first coil layer creates a step part, and when a metal film mask for patterning the second coil pattern layer by ion etching is formed on the conductor layer including this step part by dry etching. However, there is an inconvenience in that the metal film mask portion on the step portion of the conductor layer is significantly side-etched, and this causes a problem in that the patterning accuracy of the conductor layer is reduced. There is a need for a method of forming a metal film mask that can be patterned with high precision.

[Conventional technology]

Conventionally, a method for forming a metal film mask for patterning a thin film layer having steps by ion etching has been performed, for example, as shown in FIG. 2, on a substrate coated with an insulating layer (not shown). First layer coil pattern layer 1
In the case of forming a helical two-layer thin film coil of an inductive type thin film magnetic head, in which the coil pattern layer 2 and the second coil pattern layer 2 are stacked and connected through a through hole 3 in the insulating layer through an insulating layer (not shown). This will be explained using an example.

First, as shown in FIG. 3(a), a second insulating layer 24 is placed on a first conductive pattern layer 23 which is a first layer coil pattern formed on a substrate 21 via a first insulating layer 22.
A through hole 25 is formed in a predetermined region of the second insulating layer 24, and the conductor layer 2 is formed through the second insulating layer 24.
6 is applied.

Next, as shown in the third opening), titanium (TiII) for forming a metal film mask is placed on the conductor layer 26! At the same time, a predetermined resist pattern 28 is formed on the upper surface of the titanium (
Ti) 11I27 is patterned by a dry etching process using CF4 gas, and the conductor layer 26 is patterned by ion etching into a second conductor pattern layer, which becomes a second layer coil pattern, as shown in FIG. 3(0). A metal film mask 29 is formed for this purpose.

[Problem that the invention seeks to solve]

By the way, in the conventional method for forming the metal film mask 29 as described above, the conductor layer 26 of the titanium (Ti) film 27 for forming the metal film mask deposited on the conductor layer 26 is
In the titanium (Ti) 11!1127 part on the step part,
There are phenomena such as concentration of internal stress that occurs when forming a titanium (Ti) film, and the density of the adhesion being lower than that on flat areas.

Therefore, due to these reasons, when patterning the titanium (Ti) film 27 by a dry etching process to form the metal film mask 29, the step portion of the conductor layer 26 shown by A in the plan view of FIG. The etching rate of the upper Ti film 27 portion is different, and there is a problem that side etching occurs in a spiral pattern. If this is excessive, it may reach 5 .mu.- or more and may even be cut, resulting in a drawback that the pattern accuracy of the formed metal film mask 29 is significantly reduced.

This has made it difficult to accurately pattern the conductor layer 26 through an ion etching process using such a metal film mask 29.

The present invention was made in view of these conventional drawbacks.
The purpose of this is to form a metal film mask for ion etching with a relaxed level difference on the step part of the thin film layer to be patterned by ion etching, thereby preventing side etching of the metal film mask at the step part. It is an object of the present invention to provide a novel method for forming a mask for ion etching, which prevents the above problems and thereby improves patterning accuracy by ion etching of a thin film layer.

[Means for solving problems]

In order to achieve the above-mentioned object, the present invention has the following features:
As shown in FIG. 3, a second insulating layer 34 is provided on a first conductor pattern layer 33 that is patterned on a substrate 31 with a first insulating layer 32 interposed therebetween (intervening as necessary). A conductor layer 36 is applied via the wafer.

Next, a relaxation layer 37 made of a resin material is applied on the conductor layer 36 in which a step portion is formed due to the uneven surface of the first conductor pattern layer 33. A metal film 38 for forming a mask pattern for ion etching is deposited on the 1i3T, a predetermined resist pattern 39 is formed on the metal film 38, and the metal is etched by a dry etching process using the resist pattern 39 as a mask. After patterning the film 38, the relaxation layer 37 other than the patterned metal film formation region is also selectively removed by etching to form a metal film mask 40 for ion etching on the conductor layer 36.

[For production]

In the above-described method of forming an ion etching mask, a relaxation layer 3 is formed on the step portion of the conductor layer 36 to reduce the step difference.
By forming the metal film mask 40 for ion etching through the etching layer 7, the concentration of internal stress and the decrease in the adhesion density that occur when forming the adhesion of the metal film part at the step part are eliminated, and the partial side etching is eliminated. Since this is prevented, it becomes possible to easily form the metal film mask 40 for ion etching with good pattern accuracy.

Therefore, by ion-etching the conductor layer 36 using the metal film mask 40 for ion etching, it becomes possible to obtain the second conductor pattern layer 41 which becomes the second layer coil pattern with high precision.

〔Example〕

Embodiments of the present invention will be described in detail below with reference to the drawings.

FIGS. 1(a) to (dl) show an example of the method for forming an ion etching mask according to the present invention in the order of steps when it is applied to the process of forming a helical two-layer thin film coil of an inductive thin film magnetic head. FIG.

First, as shown in FIG. 1(a), 5to2. Ar10
A first insulating layer 32 made of Al.

A conductor layer made of Au+ or Cu is deposited to a thickness of approximately 3 μm by vapor deposition or sputtering, and then patterned into a predetermined pattern by wet etching, sputter etching, ion milling, etc. to form the first layer coil pattern. A first conductor pattern layer 33 is formed.

Next, the substrate 31 on which the first conductor pattern layer 33 is formed
5iQ2 on the entire top surface. After depositing a second insulating layer 34 made of Ar103 or the like to a thickness of 0.5 to 1 μm, a through hole 35 is formed in the second insulating layer 34, and an AI layer is formed on the upper surface of the second insulating layer 34.

A conductor layer 36 made of Au or Cu is deposited to a thickness of about 3 μm by vapor deposition or sputtering.

Next, a relaxation layer 37 made of a resin material such as polyimide resin (PIQ) or a resist material known by the trade name AZ1350 is coated on the conductor layer 36 to form the first conductor pattern layer. The difference in level caused by step 33 is alleviated.

Thereafter, as shown in FIG. 1('b), a metal film 38 made of titanium (Ti) or the like is deposited to a thickness of about 1 μm on the relaxation layer 37 to form a mask pattern for ion etching. A predetermined resist pattern 39 is further formed on the metal film 38.

Next, as shown in FIG. 1 (cl), the metal 11i! 38 is selectively etched by a dry etching process using CF4 gas using the resist pattern 39 as a mask, and then using the metal film 38 as a mask. By etching away the exposed relaxation layer 37 by a dry etching process using O2 gas, it becomes possible to form a metal film mask 40 for ion etching with good pattern accuracy and no side etching in the step portion.

Therefore, by selectively ion-etching the conductive film 36 immediately below using this metal film mask 40, and then selectively etching and removing only the resist pattern 39 and the metal film mask 40 by a dry etching process, As shown in FIG. 1(d), the second conductor pattern layer 41, which becomes the second layer coil pattern, can be formed with high precision.

In the above embodiment, inductive thin film magnetism is used.
Although an example has been described in which the present invention is applied to the process of forming a helical two-layer thin film coil, the essence of the present invention is not limited thereto. Needless to say, the same effect can be obtained.

〔Effect of the invention〕

As is clear from the above description, according to the method for forming an ion etching mask according to the present invention, it is easy to form a metal film mask for ion etching with a high pattern accuracy and no side etch defects on a thin film layer having a stepped portion. It has the advantage of being able to be formed into a single layer, and has excellent practical effects.

Therefore, it is extremely advantageous when applied to a patterning process by ion etching of various thin film layers having stepped portions.

[Brief explanation of drawings]

FIGS. 1(a) to 1(d) show an example of a method for forming an ion etching mask according to the present invention, which is applied to a process for forming a helical two-layer thin film coil of an inductive thin film magnetic head. 2 is a configuration diagram showing an example of a helical two-layer thin film coil of an inductive thin film magnetic head for explaining a conventional method of forming an ion etching mask; FIG. (C1 is a cross-sectional process diagram of the main part for explaining the method of forming a conventional ion etching mask, and FIG. 4 is a plan view of the main part for explaining the conventional ion etching mask. -(d), 31 is a substrate, 33 is a first conductor pattern layer, 34 is a second insulating layer, 36 is a conductor layer, 37 is a relaxation layer, 38 is a metal film, 3
9 is a resist pattern, 40 is a metal film mask for ion etching. Figure 1 tcp Figure 1 (b) 1st prisoner (C) 21NeFlyr4) r>L=+37'Ffi? 77+
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Claims (1)

[Claims] A conductor layer (36) is formed on the first conductor pattern layer (33) patterned on the substrate (31) via an insulating layer (34).
) and forming a mask pattern for ion etching thereon, prior to depositing the metal film (38) for the mask pattern, the unevenness of the first conductor pattern layer (33) is Formation of an ion etching mask characterized in that a relaxation layer (37) made of a resin material is applied on the conductor layer (36) to alleviate the level difference on the surface of the conductor layer (36) caused by the surface. Method.