Pad conditioning density distribution in CMP process with diamond dresser

In the chemical mechanical polishing (CMP) process, the pad conditioning density distribution plays a determinant role in the pad wear. A precise model and detail analysis of conditioning density function is required. To this end, at first we construct the mathematical model of polishing trajectories on the pad, then under the assumptions that the diamond grains are uniformly distributed, and slowly sweeping motion during the dressing, the conditioning density distribution for pad in CMP process is determined. This conditioning density function is verified through numerous numerical examples. In the mean time, it was also observed that to have flat distribution of pad wear rate we have to make the ratio of disk-radius-to-pad-radius small, and the effect of the pattern of grain distribution on conditioning density function is insignificant, which also agree with known results from literatures.