Preparation of flower-shaped silica abrasives by double system template method and its effect on polishing performance of sapphire wafers

As one of the most important factors of chemical mechanical polishing, abrasives have their unique mechanical grinding action and chemical action, providing the most critical support for the nanometer surface smoothness of workpieces. In this paper, the irregularly flower-shaped silica abrasives were prepared by a novel double-system microemulsion template method to replace conventional spherical silica abrasives. The synthesis principle was mainly based on heterogeneous polycondensation growth on irregular silica seeds. The morphology of the flower-shaped silica was verified by scanning electron microscopy. Due to the particularity of the synthesis method, a new environmentally friendly experimental device was designed. Chemical mechanical polishing experiments showed that the material removal rate of the flower-shaped silica with the solid content of only 6% is 217.4% of the spherical silica. The Ambios Xi-100 surface profiler showed that the surface roughness of flower-shaped silica was comparable to that of spherical silica. By establishing a contact wear model, it is analyzed that the actual contact area between the flower-shaped silica abrasives and the sapphire wafer is larger and the chemical solid phase reaction occurs more. This study provides a novel and feasible method for preparing irregularly shaped silica.