Aqueous dispersion for chemical mechanical polishing

摘要

The invention provides an aqueous dispersion for chemical mechanical polishing that is hard to putrefy, scarcely causes scratches, causes only small dishing and is suitable for used in a micro isolating step or a planarizing step of an inter layer dielectric in production of semiconductor devices. The aqueous dispersion for chemical mechanical polishing comprises ceria particles, a preservative composed of a compound having a heterocyclic structure containing a nitrogen atom and a sulfur atom in the ring, such as an isothiazolone compound, and an organic component such as organic abrasive grains composed of resin particles, a dispersing agent composed of a water-soluble polymer having a specific molecular weight or the like, a surfactant and/or an organic acid or a salt thereof contained in an aqueous medium. The ceria particles, preservative and organic component are contained in proportions of 0.1 to 20 % by mass, 0.001 to 0.2 % by mass and 0.1 to 30 % by mass, respectively, when the total proportion of the aqueous medium, ceria particles, preservative and organic component is 100 % by mass. The pH of this aqueous dispersion can be kept in a neutral range.The invention provides an aqueous dispersion for chemical mechanical polishing that is hard to putrefy, scarcely causes scratches, causes only small dishing and is suitable for used in a micro isolating step or a planarizing step of an inter layer dielectric in production of semiconductor devices. The aqueous dispersion for chemical mechanical polishing comprises ceria particles, a preservative composed of a compound having a heterocyclic structure containing a nitrogen atom and a sulfur atom in the ring, such as an isothiazolone compound, and an organic component such as organic abrasive grains composed of resin particles, a dispersing agent composed of a water-soluble polymer having a specific molecular weight or the like, a surfactant and/or an organic acid or a salt thereof contained in an aqueous medium. The ceria particles, preservative and organic component are contained in proportions of 0.1 to 20 % by mass, 0.001 to 0.2 % by mass and 0.1 to 30 % by mass, respectively, when the total proportion of the aqueous medium, ceria particles, preservative and organic component is 100 % by mass. The pH of this aqueous dispersion can be kept in a neutral range.