(1. 江苏工业学院 材料科学与工程学院，常州 213164；
2. 常州市高分子新材料重点实验室，常州 213164)
摘 要: 以正硅酸乙酯水解所得的SiO2微球为内核，采用均匀沉淀法制备具有草莓状包覆结构的CeO2/SiO2复合粉体。利用X射线衍射仪、透射电子显微镜、X射线光电子能谱仪(XPS)、动态光散射仪和Zeta电位测定仪等手段，对所制备样品的物相结构、组成、形貌和粒径大小进行表征。将所制备的包覆结构CeO2/SiO2复合粉体用于硅晶片热氧化层的化学机械抛光，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，并测量材料去除率。结果表明：所制备的CeO2/SiO2复合颗粒呈规则球形，平均粒径为150~200 nm，CeO2纳米颗粒在SiO2内核表面包覆均匀。CeO2颗粒的包覆显著地改变复合颗粒表面的电动力学行为，CeO2/SiO2复合颗粒的等电点为6.2，且明显地偏向纯CeO2；CeO2外壳与SiO2内核之间形成Si—O—Ce键，两者产生化学键结合；抛光后的硅热氧化层表面在2 μm×2 μm范围内粗糙度为0.281 nm，材料去除率达到454. 6 nm/min。
关键字: CeO2/SiO2复合磨料；包覆；化学机械抛光
（1. School of Materials Science and Engineering, Jiangsu Polytechnic University, Changzhou 213164, China;
2. Key Laboratory of Polymer Materials, Changzhou 213164, China）
Abstract:The SiO2 nanoparticles prepared by the hydrolyzing tetraethylorthosilicate were directly coated with CeO2 by chemical precipitation technique. The as-prepared samples were analyzed with X-ray diffractometry(XRD), transmission electron microscope, X-ray photoelectron spectrometer, dynamic light scatter and Zeta potential analyzer. The thermal oxide film covered silicon wafer was polished by CeO2-coated SiO2 composite abrasives, and the polishing behavior of the novel composite abrasives was characterized by atomic force microscope (AFM). The results indicate that the monodisperse, spherical CeO2-coated SiO2 particles have a particle size of 150−200 nm and are uniformly coated by the CeO2 nanoparticles. The isoelectric point of CeO2-coated SiO2 nanoparticles is about 6.2, which displays a significant shift toward pure CeO2. The shell CeO2 is chemically bounded with SiO2 core, and the Si—O—Ce bond forms between them. The surface roughness within 2 μm×2 μm area of thermal oxide film polished by CeO2-coated SiO2 composite abrasives is 0.281 nm, and the material removal rate reaches 454.6 nm/min.
Key words: CeO2-coated SiO2 composite abrasives; coating; chemical mechanical polishing
