PARTICLE FOR CHEMICAL AND MECHANICAL GRINDING, ITS PRODUCTION AND AQUEOUS DISPERSION FOR CHEMICAL AND MECHANICAL GRINDING

摘要

PROBLEM TO BE SOLVED: To provide particles useful for chemical and mechanical grinding of a metal layer such as a processed film of a semiconductor device, etc., a method for their production and an aqueous dispersion for the chemical and mechanical grinding. SOLUTION: The particles used for chemical and mechanical grinding are obtained by synthesizing by a gas phase method and coagulating fine inorganic particles having a specific value of specific surface area, and have 0.4-10μm mean particle diameter. The particles can be prepared by dispersing coagulated inorganic particles into fine particles and then coagulating them again in the presence of particles having an electric charge having a reverse sign to the electric charge of the fine particles. For example, by dispersing the coagulated silica particles to fine particles having <=0.3μm mean particle diameter, then blending cationic PMMA particles and adjusting pH to make the silica have a negative charge and the cationic PMMA have a positive charge to coagulate the fine particles again, a coagulated material having 0.4-10μm mean particle diameter is obtained. The aqueous dispersion for chemical and mechanical grinding is obtained by dispersing the above coagulated material with ion- exchanged water, etc.