Abstract: The invention provides a method of reducing in-trench smearing during polishing. The method comprises providing a substrate comprising a first layer comprising an insulating material, a second layer comprising a filling material, and a plurality of field and trench regions. A polymeric material is infiltrated over the substrate, wherein the polymeric material fills the trench regions and covers the field regions. The polymeric material optionally is removed from the field regions, followed by baking of the substrate such that the polymeric material in the trench regions becomes recessed below the insulating material of the field regions. The substrate is then subjected to a temperature of about 100° C. or more for about 30 minutes or longer, such that during polishing of the substrate, smearing of the filling material in the trench regions is reduced as compared to polishing of the substrate under the same conditions except for subjecting the substrate to the temperature of about 100° C.