單晶碳化矽晶圓(SiC)為一高崩潰電壓及低阻抗的材料，因此在高功率元件市場上有較大之需求，然而因單晶碳化矽晶圓之高硬度、高抗化學性等性質，使其在製造過程有加工時間繁長及成本高等問題。本研究主要針對單晶4H碳化矽晶圓之化學機械拋光(Chemical Mechanical Polishing, CMP)，並以降低其製程時間為目標進行研究。本研究建構一加入氧化石墨烯之複合式拋光液化學機械拋光(Hybrid-Slurry Chemical Mechanical Polishing, HSCMP)，此方法為在碳化矽之拋光液中加入適量之氧化石墨烯，增加拋光液中之OH鍵及COOH鍵，使其與碳化矽晶圓表面之鈍化層生成反應加速，達到提高製程效率的目標。研究方法先進行複合式拋光液之調配，再由橢圓偏光儀、奈米壓痕試驗機及XPS來驗證其反應之生成，發現加入氧化石墨烯之複合式拋光液，其SiO2鍵結及厚度均較普通拋光液來得厚約30 nm(92.37 %)，硬度可降低至19.08 GPa(25.36 %)。應用於兩吋碳化矽晶圓之拋光製程中，其移除率(222 nm/hr)相較於普通CMP(246 nm/hr)雖為較低之結果，但在表面粗糙度方面則有較佳之表現，以Sa < 1 nm、Ra < 0.1 nm為製程終止之條件下，HSCMP相較於CMP可達到減少30~50%之製程時間，可有效地降低碳化矽晶圓加工時間冗長之問題。

Monocrystalline Silicon Carbide (SiC) substrate has high breakdown voltage and low resistivity electrical properties, which means a great potential for applying in high power devices. However, manufacturing process of SiC wafer take very long processing time and high cost due to its ultrahigh hardness and excellent chemical stability. This study aims to improve the process time in Chemical Mechanical Polishing (CMP) of 4H SiC wafer and maintain related wafer quality. A Hybrid-Slurry Chemical Mechanical Polishing (HSCMP) has been developed with an appropriate amount of Graphene Oxide (GO) in the slurry, to activate more OH and COOH bonding. That can react with SiC wafer to generate more passivation layer on SiC wafer surface. Research method includes the preparation of hybrid slurry, and then the formation of the reaction has been confirmed by Ellipsometer, Nano Indentation and XPS. It has been found that the substrates dipping in the hybrid slurry has more SiO2 bond and reaction layer thickness of SiC wafer surface about 30 nm or increasing 92.37% than that in original slurry. The hardness also reduces to 19.08 GPa or decresing 25.36%. In CMP process of two-inch SiC wafer, the material removal rate (MRR) is lower than that of conventional CMP, but the surface roughness has better performance on Sa < 1 nm and Ra < 0.1 nm. The HSCMP can be verified to reduce the process time of 30 ~ 50% relative to CMP effectively. Results of this study can be further applied on developing new slurry for smoothing SiC wafer.

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