Patent ID: 7899571

Claim:
A method of conditioning a polishing pad, comprising the steps of: measuring a radially averaged thickness profile of an integrated circuit (IC) layer on a wafer to be polished using said polishing pad; estimating a radial profile of IC layer material of said IC layer to be removed in a chemical mechanical polish (CMP) operation using said polishing pad by subtracting a desired thickness profile of said IC layer from said radially averaged thickness profile; estimating a desired polishing pad thickness profile by a process further comprising the steps of: computing a removal rate of said IC layer material as a function of distance from a center of said wafer; and computing a polishing pad thickness as a function of distance from a center of said polishing pad required to obtain said removal rate of said IC layer material; measuring a radially averaged polishing pad thickness profile of said polishing pad; computing a conditioning sweep pattern for a conditioning block by a process further comprising the steps of: estimating a radial profile of polishing pad material to be removed from said polishing pad by subtracting said desired polishing pad thickness profile from said measured radially averaged polishing pad thickness profile; computing a removal rate of said polishing pad material from said polishing pad by said conditioning block as a function of distance from a center of said polishing pad; and computing a sweep pattern for said conditioning block which removes a desired amount of said polishing pad material such that a conditioning process using said sweep pattern will produce said desired polishing pad thickness profile on said polishing pad; and performing a conditioning process comprising the step of moving said condition block on said polishing pad in said conditioning sweep pattern.