Ceria Polishing Abrasives with Enhanced Dispersion Stability Across Wide pH Range

Ceria slurries demonstrate a high material removal rate and significant selectivity between SiO<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> and Si<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</inf>N<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</inf>, making them widely utilized in the domain of chemical mechanical polishing. Those with high dispersion stability were highly sought after, as aggregation significantly reduces polishing efficiency and surface quality. This study proposes, for the first time, that the surface modification of CeO<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> with polyacrylic acid (PAA), sulfuric acid (SA), and Akm-0530 could yield a new polishing abrasive that exhibits high stability across a broad range of pH values. Importantly, these modified CeO<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> abrasives demonstrate a specific response to variations in external pH, enabling the pH of the polishing slurry to remain stable at approximately 3-4. The crystal structure and valence state distribution of the modified CeO<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> abrasives are characterized using X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS), respectively. These modified CeO<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> abrasives possess the potential for application in chemical mechanical polishing.