Effect of pad groove geometry on material removal characteristics in chemical mechanical polishing

In this paper, we investigate the effect of groove geometry on chemical mechanical polishing (CMP) characteristics by considering the slurry duration time (SDT) and frictional behavior during CMP. XY-grooved polishing pads with different kinds of groove geometry (groove width and pitch) are considered. The dynamic coefficient of friction (COF) was measured with a piezoelectric sensor. The study revealed that the groove geometry affects the slurry flow in the wafer-pad interface and the motion of slurry abrasives, which influences the friction force, SDT, material removal rate (MRR), and within-wafer nonuniformity (WIWNU). A polishing pad having a wider groove with a small pitch has a shorter SDT and a higher COF, which guarantee better a polishing uniformity and MRR.