Polyurethane Sheet

A polyurethane layer for forming a polishing pad for a semiconductor wafer is described, wherein the polyurethane layer comprises: a foamed polyurethane, wherein the polyurethane foam has a density of about 640 to about 960 kg/m3, and a plurality of cells having an average diameter of about 20 to about 200 micrometers; and particles of a hydrophobic polymer having a critical surface energy of less than 35 mN/m and having a median particle size of 3 to 100 micrometers. Polishing pads as well as methods for polishing are also described

Polyurethane combines the strength of plastic and elasticity of rubber. PU Sheets can sustain very high loads at higher hardness than rubber. Unlike rubber it does not take part in weathering or chemical actions under normal condition and does not disintegrate easily.