Interaction of Water with Silicon Dioxide at Low Temperature Relevant to CMP

摘要

The reaction of water with silicon dioxide to form silanol species has been proposed to be a major component of the silicon dioxide chemical mechanical planarization (CMP) mechanism. Internal-reflection infrared spectroscopy was used to examine this reaction at low temperatures relevant to CMP of silicon dioxide thin films during integrated circuit manufacture (20-80 deg C). No significant reaction was observed at 20 deg C; some silanol formation was observed at 80 deg C with long exposure times. Molecular water was the predominant hydrous species observed at 80 deg C indicating that silanol formation does not contribute as significantly to the CMP removal process as previously thought.