Composite Polymer Core–Silica Shell Abrasives

Abstract

The effects of polishing time and abrasive solid content on the chemical mechanical polishing (CMP) process of blanket oxide films were investigated. Four different abrasive systems were tested in the CMP process and their performances thoroughly evaluated combining different characterization techniques. Composite abrasives achieved by either creating chemical bonds (composite A) or electrostatic attractive interactions between core and shell (composite B), were compared with conventional colloidal silica in terms of removal rate, roughness, and defectivity. In addition, the behavior of the poly(methyl methacrylate)-based terpolymer cores as abrasives in the slurry composition was investigated. While oxide CMP with composites results in shallower defects compared with conventional colloidal silica, the number of defects increases with polishing time, especially for composite B, and with an increase in solid content up to for all the abrasives.