纳米CeO_2颗粒的制备及其对硅晶片(100)和(111)的抛光性能

以硝酸铈和六亚甲基四胺为原料,在微波辐射条件下,使用乙醇/水反应体系,通过均相沉淀法制备了纳米CeO2颗粒,利用X射线衍射仪（XRD）、透射电子显微镜（TEM）、傅里叶转换红外光谱仪（FT-IR）和比表面积测定仪（BET-N2）等手段对样品的成分、物相结构、形貌、颗粒大小以及团聚情况进行了表征.将所制备的纳米CeO2颗粒作为磨料用于硅晶片（100）和（111）的化学机械抛光,用原子力显微镜（AFM）观察抛光表面的微观形貌,测量表面粗糙度,并对抛光表面划痕进行了分析.结果表明,微波辐射以及乙醇/水反应体系均有利于制备出粒径更小、分散性更好的纳米CeO2颗粒,而且微波辐射能够显著加快反应速度;经纳米CeO2磨料抛光的硅晶片（100）和（111）表面非常平整,在2μm×2μm范围内的粗糙度Ra值分别为0.275 nm和0.110 nm,获得了具有亚纳米量级粗糙度的抛光表面.

Preparation Nano-CeO_2 Particles and Its Polishing Performance for Si(100) and Si(111)

Nano-particles of CeO_2 were prepared in alcohol/water mixed solvents under microwave radiation using Ce(NO_3)_3·6H_2O and HMT as starting materials. The phase and morphology of samples were characterized by X-ray diffraction(XRD), transmission electron microscope(TEM), Fourier transform infrared spectroscopy(FT-IR) and BET-N_2. As-prepared nano-CeO_2 particles were collocated into polishing slurry for chemical-mechanical polishing of Si(100) and Si(111). The polishing behavior of nano-sized CeO_2 was studied with atomic force microscope (AFM). The results indicate that microwave radiation and alcohol/water mixed solvents are beneficial to the preparation of nano-CeO_2 powder, which is smaller in size and displays better dispersal performance, and microwave radiation can expedite the reaction rate effectively. At last, ultra-smooth surfaces of Si(100) and Si(111) with roughness (R_a) of 0.275 nm and 0.110 nm within 2 μm×2 μm area polished by nano-sized CeO_2 were obtained respectively, undulation of which was very small.