11.04.08
A polishing pad suitable for planarizing at least one of semiconductor, optical and magnetic substrates has been patented. The polishing pad comprises a polymeric matrix, which has a top polishing surface with polymeric polishing asperities or forming polymeric polishing asperities upon conditioning with an abrasive. The polymeric polishing asperities extend from the polymeric matrix and make up a portion of the top polishing surface that can contact a substrate.
The polishing pad forms additional polymeric polishing asperities from the polymeric matrix with wear or conditioning of the top polishing surface. The polymeric polishing asperities are from a polymeric material with at least 45 weight percent hard segment and a bulk ultimate tensile strength of at least 6500 psi (44.8 MPa). The polymeric matrix has a two phase structure—a hard phase and a soft phase. The two phase structure has an average area of the hard phase to average area of the soft phase ratio of less than 1.6.