POLISHING SOLUTION FOR CMP AND POLISHING METHOD

摘要

Disclosed is a polishing solution for CMP that has good dispersion stability and a high polishing rate in polishing of interlayer insulating films. Also disclosed is a polishing method. The polishing solution for CMP comprises a medium, which has been prepared in such a state that is used in a CMP polishing process, and colloidal silica particles dispersed in the medium. Preferably, the polishing solution for CMP contains 2.0 to 8.0% by mass of colloidal silica particles that simultaneously satisfy all the following three requirements. (1) The two-axis average primary particle size (R1) obtained from the images of arbitrarily selected 20 particles observed by scanning electron microscope is 35 to 55 nm; (2) the value obtained by dividing the specific surface area (S1) of the colloidal silica particles measured by BET method by the calculated specific surface area (S0) of a true sphere having the same particle size as R1 determined by (1) is 1.20 or less; and (3) the ratio (RS/R1) of the secondary particle size (RS) of the colloidal silica particles measured with a dynamic light scattering particle size distribution analyzer and R1 determined above in the polishing solution for CMP is 1.30 or less.