Abstract:

Silicon carbide （SiC） wafers， owing to their excellent physicochemical properties， are widely used in aerospace， 5G communications， and other fields. Chemical mechanical polishing （CMP） is an important method for achieving an ultra-smooth surface on SiC wafers. However， conventional polishing slurries still have drawbacks such as complex synthesis processes and high application costs. To address these issues， this study developed a Fe₃O₄/CeO₂ photocatalytic Fenton reaction system and an efficient CMP process suitable for the C-face of SiC wafers. SEM and AFM characterization results show that， after treatment with the photocatalytic polishing slurry， the surface quality of SiC is significantly improved， yielding an ultra-smooth surface. XPS valence-state analysis reveals that the electron transfer cycle formed between Fe³⁺/Fe²⁺ on the catalyst surface effectively promotes the continuous generation of hydroxyl radicals， thereby enhancing the oxidation of the SiC surface. Optimization results show that the material removal rate of the photocatalytic polishing slurry reaches 1 068 nm/h， while the surface roughness after polishing is reduced to 0.2 nm. These findings provide a new approach to the efficient， green， and ultra-precision machining of SiC materials.

Key words: SiC, Fe₃O₄, CeO₂, Fenton reaction, chemical mechanical polishing, photocatalyst