Post-dry etching cleaning liquid composition and process for fabricating semiconductor device

Abstract

A post-dry etching cleaning liquid composition for cleaning a substrate after dry etching is provided, the cleaning liquid composition containing at least one type of fluorine compound, glyoxylic acid, at least one type of organic acid salt, and water. With regard to the fluorine compound, ammonium fluoride may be used. With regard to the organic acid salt, at least one of ammonium oxalate, ammonium tartarate, ammonium citrate, and ammonium acetate may be used.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS[0001]This application is a Divisional Application of co-pending U.S. Utility application Ser. No. 11 / 145,731 filed on Jun. 6, 2005.BACKGROUND OF THE INVENTION[0002]The present invention relates to a post-dry etching cleaning liquid composition that is used in cleaning for removing a residue after dry etching, and a process for fabricating a semiconductor device using the post-dry etching cleaning liquid composition.DESCRIPTION OF THE RELATED ART[0003]In recent years, accompanying the finer structure of devices due to microfabrication and the increased performance of semiconductor circuit elements, new wiring materials and interlayer insulating film materials have been employed. For example, copper and an alloy having copper as a main component (hereinafter, called a ‘copper alloy’) have been used as new wiring materials for the purpose of reducing wiring resistance and inter-wiring capacitance. Copper wiring is formed by, for example, a damasc...

AI Technical Summary

Benefits of technology

[0021]As hereinbefore described, in accordance with the cleaning liquid composition of the present invention, since it is possible to sufficiently remove a residue formed during dry etching of an insulating film while suppressing corrosion of metal, etching of an altered layer formed on the etched surface during dry etching of the insulating film, and etching of the insulating film itself, a post-etching treatment can be carried out that is capable of removing the residue from the etched surface while maintaining the shape resulting from the etching process. Furthermore, forming the composition as an aqueous solution without using any organic solvent enables the burden on the environment to be reduced.

[0022]Furthermore, in accordance with the process for fabricating a semiconductor device of the present invention, by carrying out a cleaning posttreatment, after dry etching of an insulating film, by use of a cleaning liquid composition having the above-mentioned effects, it is possible to remove a residue from the etched surface while maintaining the shape resulting from the etching process, and it is therefore possible to complete the dry etching process with good shape precision. As a result, for example, in the damascene process, it becomes possible to improve the adhesion of a barrier layer to a side wall of a trench pattern formed by dry etching, thereby improving the reliability of the semiconductor device.

Problems solved by technology

That is, with regard to the composition 1), the amount of alkanolamine makes up 40% to 90% of the remover, and the burden on the environment is large.

However, when the composition is used in a single wafer processing system, which has been used frequently in recent years and requires a short processing time, its removal performance is not always sufficient.

Because of this, in posttreatment cleaning for dry etching using this composition, there is a possibility that the actual etching dimensions might become larger than intended etching dimensions.

Because of this, in the above-mentioned damascene process, the adhesion of a barrier layer formed in order to prevent diffusion of a metal wiring material such as copper that is to be embedded in an inner wall of a trench or a via hole formed by etching is insufficient.

There is thus the problem that the metal wiring material diffuses within the insulating film and the resistance of embedded wiring increases.

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