Supercritical carbon dioxide/chemical formulation for ashed and unashed aluminum post-etch residue removal

摘要

A post-etch residue cleaning composition for cleaning ashed or unashed aluminum/SiN/Si post-etch residue from small dimensions on semiconductor substrates. The cleaning composition contains supercritical CO₂ (SCCO2), alcohol, fluoride source, an aluminum ion complexing agent and, optionally, corrosion inhibitor. Such cleaning composition overcomes the intrinsic deficiency of SCCO2 as a cleaning reagent, viz., the non-polar character of SCCO2 and its associated inability to solubilize species such as inorganic salts and polar organic compounds that are present in the post-etch residue and that must be removed from the semiconductor substrate for efficient cleaning. The cleaning composition enables damage-free, residue-free cleaning of substrates having ashed or unashed aluminum/SiN/Si post-etch residue thereon.