Modulation of the chemical mechanical polishing performance of core-shell SnO2@CeO2 abrasives via the shape change

Abstract

The particle shape of abrasives used in chemical mechanical polishing (CMP) directly influences the polishing performance and surface quality. Here, a shape-modulation strategy is experimentally proposed for the first time to trade-off the material removal rate (MRR) and surface roughness (Ra), in which the core-shell structure SnO₂@CeO₂ abrasives were synthesized via a facile two-step wet-chemical method and the shape gradually transformed from sharp octahedron to smooth ellipsoid by changing the shell amount. Due to the combination of the higher hardness of the SnO₂ core and the chemical tooth effect of CeO₂, MRR is increased by 44.59 %–116.21 %, and Ra is reduced by 30.64 %–44.92 % compared to commercial CeO₂ abrasives. The highest polishing efficiency (MRR = 533.33 nm/min) and the most remarkable flattening ability (Ra = 0.293 nm) were achieved during the polishing of TFT-LCD glass, indicating potential applications of such novel abrasive system and further confirming the key role of abrasive particle shape and geometry on the performance of CMP.