The CMP removes material both chemically, by use of a corrosive colloidal slurry, and mechanically, by way of a wafer carrier under controlled pressure rotating against a rotating polishing pad, with carrier and pad having nonconcentric axes of rotation. It is equipped with a primary platen to remove the material and a secondary platen to do the final polish and minimize the surface roughness. The system removes irregular topography and leaves wafers planar with sub-nanometer roughness.