JPS62174994A - Thick film fine pattern - 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 Industrial Application] The present invention relates to a thick film fine pattern with high density and high reliability, and is used for small coils, high density connectors, high density wiring, etc.

[Conventional technology]

In conventional conductor patterns, the conductor thickness is thick, e.g.
In a pattern with a thickness of 5 μm, a wiring density of only 2 to 3 wires/mm has been obtained. For example, when manufacturing a motor using a coil with the above-mentioned conventional conductor pattern,
It is not possible to obtain a small, thin, and high-performance product. That is,
In order to obtain a small and thin motor with high characteristics, it is necessary to have as many turns as possible within a certain limited volume and to make the resistance as low as possible (thick conductor). However, it is not possible to obtain such a conductor pattern using conventional techniques.

The present application provides a thick film fine pattern conductor with a wiring density of 5 lines/gourd or more and a conductor thickness of 15 to 58 μm, which was previously impossible to obtain. The company provides coils, etc. for use.

[Means for solving problems]

That is, the present invention is a thick film fine butter in which a conductor having a conductor thickness of 15 to 58 μm is formed on at least one surface of a film substrate at a wiring density of 5 lines/height or more.

The thick film fine pattern of the present invention may be formed only on one side of the film-like substrate, but it may also be formed on both sides if necessary. If it is formed on both sides, the thick film fine pattern may be formed on the film-like substrate by drilling through holes. Connections need to be made. In the case of forming a plurality of patterns on one film-like substrate, it is preferable to form the patterns on both sides of the film-like substrate and connect them through through holes because it is easier to connect them.

Further, the wiring density must be 5 wires/mm or more, and preferably 10 to 20 wires/W. The conductor thickness is 15
~58 μm, preferably 20-58 μm, more preferably 35-58 μm.

As the film-like substrate used in the present invention, any film-like substrate can be used, such as polyester film, epoxy film, polyimide film, polyvarapanic acid film, triazine film, etc. However, from the viewpoint of flexibility and heat resistance, polyimide film, Boliba dipanic acid film and triazide/film are preferred. The film thickness of the film-like substrate is preferably as thin as possible in the sense of high density, but if it is too thin, workability will deteriorate, so the film thickness is preferably in the range of 5 to 50 μm, particularly 10 to 25 μm. .

Further, if necessary, an adhesive layer may be provided on one film-like substrate in order to improve the adhesion between the film-like substrate and the conductor. Adhesives include polyester-isocyanate, phenolic resin-butyral, phenolic resin-nitrile rubber, epoxy-nylon 1, and epoxy-nitrile rubber, which have excellent heat resistance, moisture resistance, and adhesive properties. are preferred, and epoxy-nitrile rubber adhesives are particularly preferred. The thickness of the adhesive is preferably in the range of 1 to 20 μm, particularly 2 to 10 μm, from the viewpoint of high density and adhesive properties.

The conductor used in the present invention may be any conductive material, but silver, gold, copper, nickel, tin, etc. are preferred, and copper is particularly preferred from the viewpoint of conductivity and economy.

The method for forming a thick film fine pattern of the present invention includes the steps of forming a patterned or unpatterned thin film conductor with a thickness of 0.1 to 10 μm on a film substrate, and a current density of 3 to 20 μm at a cathode. A conductor having a film thickness of 15 μm to 58 μm is formed by electroplating the conductor in a fine pattern 11C with a thickness of 5 to 58 μm under conditions of A/dd and K.

Methods for forming a thin film conductor with a film thickness of 0.1 to 10 μm include methods such as vapor deposition, sputtering, ion blasting, electroless plating, and pasting a copper thin film. By conventionally known photo-etching method etc., fine butter/
Alternatively, after forming a mask with JC7 photoresist on the thin film conductor and performing electrolytic plating on the fine pattern, the thin film conductor other than the fine pattern may be removed by etching or other means. good.

The film thickness of the thin film conductor is 0.1 to IOμm, especially 0.2 to 5μm.
The preferred range is μm.

Any type of electrolytic plating may be used as long as it is a conductor, but silver, gold, copper, nickel, tin, etc. are preferred, and copper is particularly preferred from the standpoint of conductivity and economy. Examples of electrolytic plating for copper include copper cyanide plating, copper pyrophosphate plating, copper sulfate plating, and borofluoride steel plating, with pyrophosphate steel plating and copper sulfate plating being particularly preferred. When electrolytically plating fine patterns, the cathode current density is an important factor. If the cathode current density is low, the plating film will become thicker in the width direction than in the thickness direction, and the plating film thickness will become non-uniform. easily, and the cathode current density is 3 to 20
A/drl, particularly 5 to I5 h/a, 1 is a preferred range. When the cathode current density exceeds 2oA/drI1, burns begin to occur. Although the electrolytic plating film thickness varies depending on the design value, a preferable range is 5 to 58 μm, particularly 10 to 50 μm.

Further, in order to further improve reliability, treatments such as heat treatment after electrolysis or the provision of a protective layer made of gold, tin, solder, or polymer are performed as necessary.

[Examples] In order to further clarify aspects of the present invention, examples will be described below, but the present invention is not limited to the following examples, and various modifications can be made.

Example 1 Polyimide film “Kapton” manufactured by DuPont (film thickness 2
5μm), surface treatment, electroless steel plating (film thickness 5μm)
), a thin film conductor pattern with a film thickness of 5 μm was formed by photoetching, and then copper 'f: Perform 20 μm thick electrolytic film Φ to obtain a film thickness of 25 μm.
A fine pattern of 12°5 lines/gI11 was obtained in μm.

Example 2 Polyba dipanic acid film “Tradron” manufactured by Esso Chemical Co., Ltd.
(film thickness 25 μm) on both sides with Bostic epoxy
After drying, nitrile rubber adhesive "XA-564-9J" was applied to a film thickness of 5 μm on one side, holes were made, and copper was deposited to form a thin film conductor with a film thickness of 0.3 μm.
Then, using a birophosphate copper plating solution manufactured by Bershoku Uchide Co., Ltd., electrolytic plating was performed to a thickness of 35 μm with copper at a cathode current density of 'IA/d-, and then the thin film other than the pattern was The copper was removed by etching to obtain a fine pattern with a film thickness of 35 μm and a density of 10 lines/mm.

Example 3 A fine pattern of 7.4 fins/fin with a film thickness of 50 μm was obtained by carrying out the same treatment as in Example 2 except that copper was electrolytically plated to a thickness of 50 μm.

【effect〕

Original EI! /c allows us to provide thick film fine pattern circuits (circuits with a film thickness of 15 to 58 μm and a wiring density of 5 lines/111I1 or more), and we can provide small coils, high-density connectors, and high-density wiring that were previously impossible to obtain. etc.

Note that the small coil can of course be applied to actuators other than motors, drive parts such as pickups and speakers, circuit parts such as transformers, inductance elements, and delay lines, and sensor parts such as FG sensors.

Claims (1)

[Claims] A thick film fine pattern characterized in that a conductor with a wiring density of 5 lines/mm or more and a conductor thickness of 15 to 58 μm is formed on at least one surface of a film substrate.