Preparation, characterization, and application of Nd-doped ceria-coated silica nanoparticles for chemical mechanical polishing

Owing to the development of electronic semiconductors and optical systems, semiconductor wafers, ceramics, and optical glass increasingly need to have higher surface quality and processing accuracy, which is placing higher demands on chemical mechanical polishing (CMP). In this paper, nano-sized ceria particles coated on the silica surface with different doping ratios of Nd3+ were designed as an abrasive and synthesized by the precipitation method. The structures and properties of binary particles were characterized using X-ray diffraction (XRD), field-emission scanning microscopy (FE-SEM), energy dispersive spectroscopy (EDS), transmission electron microscopy (TEM), UV-vis spectroscopy, and Raman spectra. CMP using the abrasives on silicon wafers was investigated and the results demonstrated an increase in polishing efficiency due to doping. The material removal rate (MRR) improved by 105% from 67.34 +/- 11.66 to 138.05 +/- 5.83 nm/min at a doping ratio of Nd3+ up to 9.1% compared with undoped abrasives.