Slurry-induced pad wear rate in chemical mechanical planarization

In this study, the extent of the pad wear rate during the shallow trench isolation chemical mechanical planarization process was investigated for several combinations of the type of abrasive particles (i.e., colloidal and fumed silica), abrasive content, and abrasive concentration. Results showed a relation between pad wear rate and abrasive concentration for both fumed and colloidal slurries. Results indicated that the pad wear rate using the colloidal silica slurry was higher by approximately 42 and 6% at 3 and 25 wt % silica, respectively. Under the same abrasive content, pad wear rate for fumed slurry was 23% higher compared to colloidal slurry.