Photoresist stripping solution and a method of stripping photoresists using the same

Abstract

A photoresist stripping solution which comprises (a) a salt of hydrofluoric acid with a base free from metal ions, (b) a water-soluble organic solvent, (c) a mercapto group containing corrosion inhibitor, and (d) water, and a method of stripping photoresists with the use of the same are disclosed. In case of using ammonium fluoride as component (a), the photoresist stripping solution may further contain (e) a salt of hydrof luoric acid with a quaternary ammonium hydroxide, such as tetramethylammonium hydroxide, tetrapropylammonium hydroxide, etc., and / or an alkanolamine. The photoresist stripping solution of the present invention has an excellent effect of protecting both Al- and Cu-based metal wiring conductors from corrosion, of efficiently stripping photoresist films and post-ashing residues, and is free from the precipitation of the corrosion inhibitor.

Description

[0001] This is a continuation of Ser. No. 10 / 973,302, filed Oct. 27, 20004, which is a continuation of Ser. No. 10 / 208,096, filed Jul. 31, 2002, now abandoned.BACKGROUND OF THE INVENTION [0002] 1. Field of the Invention [0003] This invention relates to a photoresist stripping solution and a method of stripping photoresists using the same. More particularly, it relates to a photoresist stripping solution which is excellent in protecting both Al- and Cu-based wiring conductors and other metal conductors from corrosion and in stripping photoresist films and post-ashing residues; and a method of photoresists using the same. The present invention is suitable for use in the fabrication of semiconductor devices such as ICs and LSIs, as well as liquid-crystal panel apparatus. [0004] 2. Description of Relevant Art [0005] The fabrication of semiconductor devices such as ICs and LSIs, as well as liquid-crystal panel apparatus, comprises forming a uniform photoresist coating over conductive met...

AI Technical Summary

Benefits of technology

"The present invention provides a photoresist stripping solution that is suitable for use in the photolithographic technology to form semiconductor and liquid-crystal display devices with decreasing feature size and increasing number of interlevel films superposed on the substrate. The solution can effectively protect against corrosion of wiring metal conductors and efficiently strip the photoresist film and post-ashing residues. The solution includes a salt of hydrofluoric acid with abase free from metal ions, a water-soluble organic solvent, a mercapto group containing corrosion inhibitor, and water. Additionally, the solution may further contain a salt of hydrofluoric acid with a quaternary ammonium hydroxide or an alkanolamine. The method of stripping photoresists involves forming a pattern on a substrate, etching the substrate, and then using the photoresist stripping solution to remove the pattern and any post-etching residues."

Problems solved by technology

The resist stripping solution composition in JP-A-9-197681 is to a certain extent effective in strippability and antiorrosivity on semiconductor devices having Al wiring conductors, however, it fails to exert any satisfactory effect of protecting devices having Cu wiring conductors from corrosion.

Although the corrosion of Cu wiring conductors can be relieved to a certain extent by using these compounds, there arises another problem that strippability for Cu-based metallic depositions (residues) is still insufficient.

However, any satisfactory strippability for Cu-based metallic depositions (residues) also cannot be established by using this cleaner solution.

As discussed above, none of the conventional photoresist stripping solutions can satisfy both of the requirements for efficient strippability and effective inhibition of metal corrosion.

That is to say, there is a problem that one of the above-described requirement cannot be fulfilled unless the other is sacrificed.

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