AQUEOUS DISPERSIONS, PROCESS FOR THEIR PRODUCTION AND THEIR USE

摘要

PURPOSE: A process of preparing aqueous dispersions containing only a little amount of impurities by introducing cerium oxide whose average particle size in the dispersion is less than 100 nm through an aerosol of a cerium salt solution or suspension and then dispersing the cerium oxide-doped, pyrogenically produced silicon dioxide in aqueous solution is provided. Thus obtained aqueous dispersion can be used for chemical-mechanical polishing. CONSTITUTION: The aqueous dispersion is produced by dispersing a cerium oxide-doped, pyrogenically produced silicon dioxide in an aqueous solution by means of a high energy input and contains a solid content of 0.1 to 70% by weight and a pH value of 3 to 11. The doped cerium oxide has a cerium content of 10ppm to 10% by weight and a BET surface area of 5 to 600m¬2/g.