An amine-free composition and process for cleaning post-chemical mechanical polishing (CMP) residue and contaminants from a microelectronic device having said residue and contaminants thereon. The amine-free composition preferably includes at least one oxidizing agent, at least one complexing agent, at least one basic compound, and water and has a pH in the range from about 2.5 to about 11.5. The composition achieves highly efficacious cleaning of the post-CMP residue and contaminant material from the surface of the microelectronic device without compromising the low-k dielectric material or the copper interconnect material.