ABSTRACT
Post-CMPcleaningisrequiredforaneffectiveremovalofresidualslurryandimpuritiesfromthewafersurface.Theslurry,containingsilicaoraluminaparticles,
can remain on the surface of the wafer after chemical mechanical polishing. After polishing undesirable metallic contamination may remain on the surface of the wafer. All contamination, whether in the form of particles, organic residue, metallic contamination or undesirable oxidation, must be removed. If the contamination is not removed, defects and poor device performance would cause a reduction in device yield. Post-CMP cleaning techniques must remove these contaminants without altering the physical and chemical characteristics of the films that are being cleaned. Figure 1 shows the technical cleaning challenges in post-CMP cleaning of the back end ofline (BEOL) dual damascene structures.
