Chemical-mechanical polishing of low dielectric constant poly(silsesquioxane): HSQ

In this study, the chemical-mechanical polishing (CMP) characteristics of the low dielectric constant poly(silsesquioxane) (HSQ) were investigated. CMP behavior was studied using different kinds of slurries, additives, and pads. The slurriesused included SiO2 based slurry (SS-25). ZrO2 based slurry (A-1), and Al2O3 based slurry (WA400). The additives used to change the surface interaction behavior were Triton X-100 and HNO3. The role of the polishing pad was investigated by a hard pad (IC 1400) and a soft pad (Politex). The experimental results suggested that the hardness of the abrasives and pads and the electrostatic interaction between the abrasive and polymer surface were responsible for the polishing results.