In this paper, we will present the study of the use of H{sub}2O{sub}2 in ammonia (essentially an SC1 process) in the post CMP cleaning process for STI CMP in which CeO{sub}2 based slurry is used. It is discovered that when properly mixed, this chemistry helps to improve the removal of ceria particles. The mechanism is believed to be the breaking of the loosely formed Si-O-Ce bonds by the O-O group in the H{sub}2O{sub}2. The cleaning efficiency is clearly a function of the concentration of H{sub}2O{sub}2 in the mix, and the use of megasonics. A fairly efficient SC1 process is developed based on these understandings and achieves <80 total defects at ≥0.15 μm particle size. The process is also stable over a significant number of wafers. Two slurries are studied: Hitachi HS8005 + HS81O2GP and EKC CMP 2100. Similar results are observed.
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