Post-CMP cleaning of semiconductor wafer surfaces using a combination of aqueous and CO2 based cryogenic cleaning techniques

摘要

The present invention provides for a new and improved method of aqueous and cryogenic enhanced (ACE) cleaning for semiconductor surfaces as well as the surfaces of metals, dielectric films particularly hydrophobic low k dielectric films, and CMP etch stop films to remove post-CMP contaminants. It is particularly useful for removing contaminants which are 0.3 mum in size or smaller. The ACE cleaning process is applied to a surface which has undergone chemical-mechanical polishing (CMP). It includes the steps of cleaning the surface with an aqueous-based cleaning process, at least partially drying the surface, and, shortly thereafter, cleaning the surface with a CO2 cryogenic cleaning process. This process removes such contaminants from surfaces which are hydrophobic and hence difficult to clean with aqueous-based cleaning techniques alone.