Aqueous metal polishing agent comprising a polymeric abrasiv containing pendant functional groups and its use in a cmp process

An aqueous polishing agent, comprising:

• solid polymer particles as an abrasive, finely dispersed in an aqueous phase, and
• an organic non-polymeric compound as a complexing agent, dissolved in the aqueous phase,
• wherein the polymer particles comprise
• a pendant functional group (a1) capable of strongly interacting with a metal of, a metal oxide on top of, or both a metal of and a metal oxide on top of a surface to be polished, and capable of forming a strong complex with the metal, and
• a pendant functional group (a2) capable of interacting less strongly with the metal of the surface to be polished than the functional group (a1);
• and
• wherein the organic, non-polymeric compound is a compound capable of
• interacting with the metal, the metal oxide, or both the metal and the metal oxide on top of the surface to be polished,
• forming a strong, water-soluble complex with the the metal, and
• causing an increase of a material removal rate MRR and a static etch rate SER of the surface to be polished with increasing concentration of the organic non-polymeric compound in the aqueous polishing agent.