Silica-based composite fine-particle dispersion method for producing same and polishing slurry including silica-based composite fine-particle dispersion

摘要

The subject of the present invention is a semiconductor device such as a semiconductor substrate wiring board since it is capable of polishing silica films, Si wafers, and materials that are difficult to process at high speed, and at the same time does not contain impurities capable of achieving high surface precision (low scratches, etc.). It is to develop a silica-based composite fine particle dispersion that can be preferably used for polishing the surface. The problem solving means of the present invention includes a silica-based composite fine particle having the following characteristics, having a silica film covering the crystalline ceria as a main component on the surface of the parent particle containing amorphous silica as a main component, and covering them. It is to provide a silica-based composite fine particle dispersion. The mass ratio of the parent and child particles is within a specific range. When X-ray diffraction is applied, only the crystal phase of ceria is detected. The crystallite diameter of the (111) plane of crystalline ceria (around 2θ = 28 degrees) is a specific range. The low content rate of Na etc. The ratio of the number of Si atoms to the% of Ce atoms in the silica film is a specific range.