Investigating the effect of diamond size and conditioning force on chemical mechanical planarization pad topography

Pad conditioning plays an important role in chemical mechanical planarization processes as it directly impacts pad topography and polishing performance. As predicted by the conditioning, friction and removal rate theories, the conditioning process impacts polishing rate through a key measure of the pad surface known as surface abruptness (λ). In this study, incremental loading as well as interferometry methods are used to analyze pad surface topography in terms of λ when the pads are conditioned using discs with different diamond grit sizes at different loads. Moreover, the pad surface is analyzed mechanically and compared in both dry and moist conditions. Results agree well with the theoretical predictions both in the dry and the moist conditions.