JPS61129854A - Manufacture of thin film conductor - Google Patents

Abstract

PURPOSE:To manufacture the copper thin film conductor by facilitating its soldering by a method wherein an Al thin film is adhered on a substrate and formed into a photo resist pattern by photoetching, and next a copper thin film is adhered and formed into thin film conductor by lift-off. CONSTITUTION:Dichromium or titanium 2 for adhesion reinforcement is adhered on the substrate 1, and the Al thin film 3 is adhered. Thereafter, a photo resist is applied, exposed to ultraviolet rays with a photo mask, and then developed into the desired photo resist pattern 4. Next,the photo resist is exfoliated by removing the unnecessary metallic parts by etching. Then, another photo resist pattern 5 is formed on the Al thin film, and the copper thin film 6 is adhered. The unnecessary Al thin film is removed together with the photo resist by lift-off using flux or an adhesive tape, thus producing a desired copper thin film conductor.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a thin film conductor for a hybrid integrated circuit, and in particular to a thin film conductor for a hybrid integrated circuit, in particular for use in external lead terminals, active elements, etc. using aluminum and copper thin films as conductors.
The present invention relates to a method of manufacturing a conductor circuit in which connection with passive elements is performed by bonding and soldering.

[Conventional technology]

Conventionally, the manufacturing method for thin film conductor circuits in hybrid integrated circuits is to deposit a thin film of tantalum or other passive element metal on a substrate, then deposit a thin film of nichrome or the like as an intermediate layer for adhesion reinforcement, and then deposit a gold thin film. After the entire surface is deposited, a resistor circuit pattern and a conductor circuit pattern are formed by photo-etching. Alternatively, a metal thin film such as nichrome for adhesion reinforcement was applied on the substrate, then a copper thin film was applied, and then an aluminum thin film was applied, and the aluminum thin film portion and the aluminum on the copper thin film were partially removed using photoresist and selective etching methods. A conductor circuit pattern consisting of a copper thin film portion is formed. Conductor i generally made of a thin gold film
is an external lead terminal and a passive element.

Active elements are connected by bonding and soldering. The conductor part consists of an aluminum thin film part and a copper thin film part, and there are difficulties in soldering to aluminum and bonding to copper.External terminals and passive elements are made by bonding for the aluminum thin film part and soldering for the steel thin film part. , active element connections are made.

[Problem that the invention seeks to solve]

In the conventional conductor manufacturing method described above, the former method can be used for bonding and soldering because it is difficult to oxidize due to the characteristics of gold, so it can be connected relatively easily, but it has the disadvantage of increasing the cost of the product because it is expensive. The latter is a cheap metal, but has the property of being easily oxidized. Also, the substrate - Nichrome - Copper -
Depending on the structure of the aluminum, when performing selective etching using a photoresist, the film portion of the aluminum surface is etched to form an exposed copper surface, or after a photoresist pattern is formed on the aluminum surface,
The manufacturing method involves simultaneously etching aluminum and copper to form a conductor circuit pattern, then removing the photoresist, forming a photoresist pattern that exposes a portion of the aluminum again, and then etching the aluminum. At the end point of gradual etching, the copper and aluminum etching solution (FLL, +7 phosphoric acid, nitric acid type) come into contact with each other, which tends to corrode the steel surface and cause oxidation, which is a disadvantage in reducing solderability.

[Means for solving problems]

The purpose of the present invention is to minimize corrosion and oxidation of steel thin film conductor parts in a conductor enclosure consisting of a copper thin film and an aluminum thin film in connection with the formation of a thin film conductor circuit of a hybrid integrated circuit.
After a metal thin film such as nichrome or titanium for adhesion reinforcement is deposited on the tantalum passive element thin film deposited on the substrate or directly on the substrate, an aluminum thin film is deposited on the entire surface, and then the desired aluminum conductor is formed by photo-etching. A pattern or a passive element pattern is formed, the photoresist pattern is released, and then a desired photoresist pattern is formed again on the aluminum conductor pattern, after which a copper thin film is deposited, and a steel thin film conductor section is formed on the aluminum thin film conductor by the IJ7 to-off method. It has a manufacturing method in which it is formed by overlapping.

〔Example〕

Next, the VC1 invention will be explained with reference to the drawings.

FIG. 1 is a longitudinal sectional view of one embodiment of the present invention.

As shown in Figure 1 (al), nichrome or titanium/2 for adhesion reinforcement is adhered onto the substrate 1, and then a thin aluminum film 3 is deposited, and then photoresist is applied and exposed to ultraviolet Iw! using a photomask. , developed and desired photoresist butter/l-
(Fig. 1 φ)).

Next, all unnecessary metal parts are removed by etching, and the photoresist is peeled off. (Figure 1 (C)). Next, a photoresist pattern 51 is again formed on the aluminum thin film, and then a steel thin film 6 is applied (FIG. 1(d)). Thereafter, unnecessary aluminum thin film gold is removed from each photoresist using a solvent or adhesive tape or by a 7-off method to obtain a desired steel thin film conductor (FIG. 1 (C1)).

〔Effect of the invention〕

As explained above, the present invention provides a thin film conductor circuit in which external terminals, active elements, and passive elements can be connected by both soldering and bonding. Form the photoresist butter/l- again, then apply the steel thin PT-* to form the steel thin film conductor part by the lift-off method. VC process Q, prevent oxidation as much as possible since it does not involve contact with the aluminum etching solution. This has the effect of making soldering of copper thin film conductors easier than before.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view showing an embodiment of the present invention. 1...Substrate, 2...Nichrome or titanium/, 3...Aluminum, 4. 5-... Photoresist, 6... Copper. Agent Patent Attorney Original Purpose...'-2S'
,,7r, small'・2, -3°

Claims (1)

[Claims] After depositing a metal thin film for a tantalum-based passive element on a substrate, or after depositing a metal thin film for adhesion reinforcement on a substrate, a process of depositing an aluminum thin film for a conductor, the conductor film, and adhesion. a step of forming a reinforcing film and a metal film for passive elements into a desired pattern by photoetching; a step of applying a photoresist to the substrate after the pattern formation; and a step of forming a desired photoresist pattern on a part of the aluminum conductor section; 1. A method for manufacturing a thin film conductor, comprising the steps of depositing a copper thin film on a formed substrate and removing the photoresist and unnecessary metal film by a lift-off method.