An improved slurry composition and methods of using it are provided for final polishing of silicon wafers. The composition comprises water, submicron silica particles between 0.2 and 0.5 percent by weight of this composition, a salt at a concentration of about 100 to about 1000 ppm, an amine compound at a concentration sufficient to effect a composition pH of about 8 to about 11, and a polyelectrolyte dispersion agent at a concentration of about 20 to about 500 ppm, wherein the composition has a total sodium and potassium content below about 1 ppm, and an iron, nickel, and copper content each below about 0.1 ppm, all ppm being parts per million by weight of the composition.