A CMP polishing pad improves overall material removal rate uniformity by combining multiple polishing pad sections in a serially linked manner, where the polishing pad sections are characterized by at least two different material removal rate profiles. The polishing pad is designed by determining a wafer...http://www.google.se/patents/US6261168?utm_source=gb-gplus-sharePatent US6261168 - Chemical mechanical planarization or polishing pad with sections having varied groove patterns
