Academic Journal of Materials & Chemistry, 2024, 5(1); doi: 10.25236/AJMC.2024.050106.
Zhu Qiqi
Chongqing Jiaotong University, Chongqing, 400074, China
This manuscript provides an introduction to third-generation semiconductor material, single-crystal silicon carbide (SiC), offering a concise overview of its fabrication process. It delves into the chemical mechanical polishing of SiC wafers employing silica (SiO2) and ceria (CeO2) abrasives; it examines the variations in the wettability of SiC surfaces with pH changes, noting reduced contact angles and increased spreading coefficients in highly acidic and alkaline conditions. The study further analyzes the impact of SiO2 abrasive concentration, revealing that an increase to 8wt% leads to a peak material removal rate of 185 nm/h. Predictive forces based on DLVO theory suggest that SiO2 particles are prone to adhesion on the wafer surface within the pH range of 2-5, primarily due to DLVO-induced electrostatic attraction, which can result in surface contamination. In contrast, adsorption theories predict that CeO2 particles are likely to adhere to the wafer surface in both acidic and alkaline solutions, predominantly through the chemical chelating actions of CeO2 particles, without contaminating the surface.
Single-crystal SiC; Chemomechanical polishing; SiO2 abrasives; CeO2 abrasives; DLVO theory; Adsorption phenomena; Zeta potential
Zhu Qiqi. The exploration of DLVO theory and adsorption principles during the polishing process of 6H-SiC wafers with SiO2 and CeO2 abrasives. Academic Journal of Materials & Chemistry (2024) Vol. 5, Issue 1: 31-37. https://doi.org/10.25236/AJMC.2024.050106.
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