| abstract |
This invention provides a polishing agent composition for polishing the surface of an insulating film comprising an organic silicon material having a C-Si bond and a Si-O bond for use in a semiconductor integrated circuit, which comprises water and particles of a specific rare earth element compound selected from the group consisting of a rare earth element hydroxide, a rare earth element fluoride, a rare earth element oxyfluoride, a rare earth element oxide except cerium oxide, and a composite compound formed therefrom; and the polishing agent composition which further comprises cerium oxide particles. The above polishing agent composition can provide a high quality polished surface which is free from or reduced in the occurrence of defects such as cracked, scratched or exfoliated portions or micro defects. |