Washing liquid for post-polishing and polishing-cleaning method in semiconductor process

摘要

A polishing treatment called CMP (chemical mechanical polishing) is utilized for filling a contact hole formed in a silicon oxide film with a metallic layer in a manufacturing process of a semiconductor device. After a CMP treatment, a target surface, on which the silicon oxide film and the metallic layer are exposed, is washed with a washing liquid so as to remove residues due to the CMP treatment. The washing liquid comprises a fluorine compound for providing an etchant for the silicon oxide film and the metallic layer, and a protective agent which can be adhered onto a surface of the metallic layer so as to form a protective film. The ratio between the fluorine compound and the protective agent is set such that etching rates of the silicon oxide film and the metallic layer to be effected by the washing liquid fall within ranges of from 0.5 nm/min to 5 nm/min and from 0.5 nm/min to 6 nm/min, respectively, and a ratio between these etching rates falls within a range of from "2:1" to "1:3".