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Chemical mechanical polishing (CMP) is a crucial step in integrated circuit manufacturing, and as chip feature sizes continue to shrink, there is an escalating demand for improved polishing performance. In this study, monodisperse porous CeO 2 nanospheres were synthesized and then modified through Nd doping. The structural and chemical characterization confirmed the enrichment effect on surface defects (Ce3+ and oxygen vacancies) due to the doping, with the percentage of Ce3+ in pCeO 2 -Nd materials (39%) being higher than that of pCeO 2 (31%). Furthermore, for the CMP application on silicon wafers, the material removal rate (MRR) of pCeO 2 -Nd reached 126.3 ± 17.5 nm/min, which is a 56% improvement over that of pCeO 2. In addition, the surface roughness (Ra) of the localized area (3 × 3 μm2) was reduced from initially 0.813 ± 0.02 nm to 0.296 ± 0.02 nm after polishing with pCeO 2. The chemical bonding of Ce–O–Si is considered to be the bridge between the structural characteristics of the abrasive and the polishing properties, whose presence makes the CMP process more efficient and high-quality. 1. Synthesized monodisperse porous abrasives pCeO 2 for polishing of silicon wafer.2. Dopant modification and heat treatment processes were investigated to obtain pCeO 2 -Nd abrasives.3. The material removal rate of pCeO 2 -Nd was increased by 56% compared to that of pCeO 2. [Display omitted] • Synthesized monodisperse porous abrasives pCeO 2 for polishing of silicon wafer. • Dopant modification and heat treatment processes were investigated to obtain pCeO 2 -Nd abrasives. • The material removal rate of pCeO 2 -Nd was increased by 56% compared to that of pCeO 2. • Wafer roughness can be reduced from 0.813 nm to 0.296 nm after polishing with pCeO 2. [ABSTRACT FROM AUTHOR]

With the pursuit of high efficiency and quality chemical mechanical polishing (CMP), exploring additional efficiency enhancement means based on the CMP has become a trend. Polystyrene/CeO 2 core-shell abrasives (core: 85 nm, shell: 10 nm) doped with Lanthanide (La, Nd, and Eu) were synthesized by a modified in situ chemical precipitation method, promising application for photocatalytic-assisted CMP of silica wafer. The doping of La, Nd, and Eu can reduce the band gap of CeO 2 from 3.24 eV to 3.23 eV, 3.20 eV, and 3.22 eV, respectively, indicating enhanced photocatalytic activity. Especially for Nd-doped abrasives, the content of Ce3+ increases from 0.49 to 0.56, accompanied by the generation of oxygen vacancies, as proved by X-ray photoelectron spectroscopy (XPS) and Raman spectra. In addition, the prepared polishing slurry could remain stable for up to 7 days by the steric hindrance effect and electrostatic repulsion of the dispersants. The materials removal rate of Nd-doped abrasive in photocatalytic-assisted CMP of SiO 2 films reaches 174.3 ± 7.6 nm/min, which is 163% higher than those in CMP, while the surface roughness (Ra) in localized areas (2×2 µm2) can be reduced from the initial 0.82 ± 0.01 nm to 0.36 ± 0.05 nm. Detailed reaction and removal mechanism involved in photocatalytic-assisted CMP processes is discussed. [Display omitted] • Synthesized RE3+ doped PS-CeO 2 core-shell abrasives for polishing of silicon wafer. • Addressed the issue of abrasive agglomeration by adding dispersants. • The polishing rate of Nd-doped abrasives is increased by 163 % under UV, and the roughness can be reduced from 0.82 nm to 0.36 nm. [ABSTRACT FROM AUTHOR]

With the pursuit of high efficiency and quality chemical mechanical polishing (CMP), exploring additional efficiency enhancement means based on the CMP has become a trend. Polystyrene/CeO 2 core-shell abrasives (core: 85 nm, shell: 10 nm) doped with Lanthanide (La, Nd, and Eu) were synthesized by a modified in situ chemical precipitation method, promising application for photocatalytic-assisted CMP of silica wafer. The doping of La, Nd, and Eu can reduce the band gap of CeO 2 from 3.24 eV to 3.23 eV, 3.20 eV, and 3.22 eV, respectively, indicating enhanced photocatalytic activity. Especially for Nd-doped abrasives, the content of Ce3+ increases from 0.49 to 0.56, accompanied by the generation of oxygen vacancies, as proved by X-ray photoelectron spectroscopy (XPS) and Raman spectra. In addition, the prepared polishing slurry could remain stable for up to 7 days by the steric hindrance effect and electrostatic repulsion of the dispersants. The materials removal rate of Nd-doped abrasive in photocatalytic-assisted CMP of SiO 2 films reaches 174.3 ± 7.6 nm/min, which is 163% higher than those in CMP, while the surface roughness (Ra) in localized areas (2×2 µm2) can be reduced from the initial 0.82 ± 0.01 nm to 0.36 ± 0.05 nm. Detailed reaction and removal mechanism involved in photocatalytic-assisted CMP processes is discussed. [Display omitted] • Synthesized RE3+ doped PS-CeO 2 core-shell abrasives for polishing of silicon wafer. • Addressed the issue of abrasive agglomeration by adding dispersants. • The polishing rate of Nd-doped abrasives is increased by 163 % under UV, and the roughness can be reduced from 0.82 nm to 0.36 nm. [ABSTRACT FROM AUTHOR]