Thin Solid Films, Vol.618, 77-80, 2016
Cleaning methodology of small residue defect with surfactant in copper chemical mechanical polishing post-cleaning
Advanced semiconductor manufacturing technology has adopted an alkaline solution for copper (Cu) corrosion prevention instead of the traditional acidic solution in the post-cleaning process of copper chemical mechanical polishing. Low particle and residue removal efficiency has been an issue for this process. In this study, we investigated the formation of small residue defects and the cleaning mechanism to remove these defects. The results show it is insufficient to remove the small residue defects by using the traditional process parameter tuning. Adding some friction between the pad and the wafer surface allowed the defects to be effectively reduced. (C) 2016 Elsevier B.V. All rights reserved.
Keywords:Abrasive;Copper;Chemical mechanical polishing;Post-cleaning;Tetramethylammonium hydroxide (TMAH);Citric acid;Perfiuorobutanesulfonic acid (PFBS)