POLISHING SOLUTION FOR CMP AND POLISHING METHOD

摘要

The present invention can provide a polishing liquid for CMP having good dispersion stability and a high polishing rate in polishing of interlayer insulating films and a polishing method. Disclosed a polishing liquid for CMP comprising: a medium; and colloidal silica particles dispersed in the medium, a blending amount of the colloidal silica particles being 2.0 to 8.0% by mass relative to 100% by mass of the polishing liquid, wherein the colloidal silica particles satisfy the following conditions (1) to (3): (1) a two-axis average primary particle diameter (R1) obtained from images of twenty arbitrarily selected colloidal silica particles observed by a scanning electron microscope is within the range of 35 to 55 nm; (2) a value S1/S0 obtained by dividing a specific surface area (S1) of a colloidal silica particle measured by BET method by a calculated specific surface area (S0) of a true sphere having the same particle diameter as the two-axis average primary particle diameter (R1) determined by (1) above is 1.20 or less; and (3) a ratio, association degree: RS/R1, of a secondary particle diameter (RS) of the colloidal silica particles measured with a dynamic light scattering particle size distribution analyzer and the two-axis average primary particle diameter (R1) determined by (1) above in the polishing liquid for CMP is 1.30 or less.