Field of the Invention
The present invention relates to a cleaning liquid and a cleaning method using the cleaning liquid.
Related Art
When semiconductor elements such as IC and LSI, or display elements such as liquid crystal panels are manufactured, a CVD vapor-deposited metal film or an insulating film such as a SiO2 film is first firmed on a substrate such as a silicon wafer or glass. Next, a photoresist pattern or a metal hard mask is formed on the metal film or the insulating film. Then, the substrate is subjected to dry etching using this photoresist pattern or this hard mask as a mask to form a fine circuit. Next, after the pattern or the mask is ashed, residual materials of the photoresist pattern and the residual materials of the hard mask are cleaned and removed using a cleaning liquid.
In elements provided with such a fine circuit formed of a metal film, miniaturization of a circuit is increasingly progressed. In many cases, copper is used as a material of a metal film during formation of a fine circuit. However, in a case of further performing miniaturization of the circuit, there is a problem in that electromigration is easily caused in the fine circuit formed of a copper film.
For this reason, in a case of forming an extremely fine circuit, coating the surface of the circuit with an alloy containing cobalt or cobalt has been proposed in order to prevent electromigration.
On the other hand, it is expected for the cleaning liquid, which can be used in order to clean and remove residual materials of the photoresist pattern and residual materials of the hard mask, to be able to effectively clean and remove these residual materials and to have excellent anticorrosion properties with respect to metals. Use of hydrofluoric acid and a compound in which ammonia is used as a counter amine thereof (refer to Japanese Unexamined Patent Application, Publication No. 2001-83713, Japanese Unexamined Patent Application, Publication No. H9-197681, and Japanese Unexamined Patent Application, Publication No. 2000-47401), hydrofluoric acid and a compound in which 1,8-diazabicyclo[5.4.0]undecene-7 is used as a counter amine thereof (refer to Japanese Unexamined Patent Application, Publication No. 2000-181083), or the like, as such a cleaning liquid has been proposed.