A study of post-chemical-mechanical polish cleaning strategies

Chemical-mechanical polishing (CMP) has emerged as the premier technique for achieving both local and global planarization. One of the primary concerns in the use of CMP, however, is the efficient and complete removal of CMP contaminants such as slurry and residual hydrocarbons. This paper discusses the removal of silica-based slurries utilized for polysilicon and oxide CMP processes. The effects of mechanical brush cleaning, chemical treatments, and polish processes on defect density for a 16 Mb memory technology are presented. In addition, the chemical compatibility of polishing slurries with various brush and polishing pad materials is discussed.