Colloidal polishing of fused silica

摘要

A polishing application uses alkali, colloidal silica for polishing fused silica. Preferably, the silica solutions are adjusted to a pH of or above 10. The polished fused silica surfaces have surface finishes consistently below 2 ANGSTROM Ra. The unique method first polishes a surface of the substrate with an aqueous solution of at least one metal oxide abrasive and further polishes the surface of the substrate with an alkali aqueous solution of colloidal silica. Preferably, to the final smoothness of 2 ANGSTROM Ra or less.