Study on fine particle behavior in slurry flow between wafer and polishing pad as a material removal process in CMP

Inhalt:
The material removal mechanism in CMP process still remains not fully understood. It has traditionally been assumed that material removal proceeds as slurry particles perform micro cutting in the contact area between a chemical reacted layer formed on the wafer surface and the polishing pad. However, this assumption cannot explain various phenomena observed during the CMP process. Thus, a major challenge is to clarify the real mechanism of material removal. This study discusses the material removal mechanism in CMP process based on the observation of behavior of particles in slurry. The observation of particle’s behavior in the evanescent light field is carried out. Keywords : Chemical-mechanical Polishing, material removal mechanism, evanescent light, particle, slurry