Chemical mechanical planarization method and apparatus for improved process uniformity, reduced topography and reduced defects

摘要

A method and apparatus for utilizing an optimized polishing pad to increase planarity and reduce defects in CMP processing. The optimized polishing pad includes a polishing surface to remove material from and maintain a uniform polish rate with respect to a wafer surface. The polishing pad has a hardness between 62 and 98 shore A and a tensile modulus between 3,500 and 35,000 psi. A three-stage CMP process utilizes a hard pad, a first optimized pad and a second optimized pad to increase planarity while reducing surface defects.