Performance of water-soluble fullerenol as novel functional molecular abrasive grain for polishing nanosurfaces

We propose a novel chemical-mechanical polishing (CMP) technique for use as the planarization method in the Cu damascene process for the fabrication of next-generation semiconductors. Water-soluble fullerenol, which has attractive features such as a 1-nm grain size, high water dispersibility in a molecular level and metal free, is used in this technique. Chemical process analysis reveals the chemical and mechanical functions of water-soluble fullerenol molecules as abrasive grains. Experimental results show that Cu-surface roughness was improved from 20 to 0.6 nm RMS by using C₆₀(OH)₃₆ fullerenols as functional molecular abrasive grains to achieve better polishing performance than conventional processes.