采用射频磁控溅射法制备了ZnS SiO2 介电薄膜 ,利用透射电镜和椭偏仪研究了溅射条件对ZnS SiO2薄膜微结构和折射率n的影响 研究表明 ,ZnS SiO2 薄膜中存在微小晶粒 ,大小为 2～ 10nm的ZnS颗粒分布在SiO2 基体中 ,当溅射功率和溅射气压变化时 ,ZnS SiO2 薄膜的微结构和折射率n发生显著变化 ,微结构的变化是导致折射率n变化的主要原因 ,通过优化溅射条件可以制备适用于相变光盘的高质量ZnS SiO2 介电薄膜 ZnS SiO2 dielectric thin films were prepared by radio-frequency magnetron sputtering. The effects of sputtering conditions on the microstructure and refractive index n of ZnS SiO2 thin films were studied by transmission electron microscopy and ellipsometry. The results show that there are tiny grains , ZnS particles of size 2 ~ 10nm are distributed in the SiO2 matrix. When the sputtering power and sputtering pressure change, the microstructure and refractive index n of ZnS SiO2 film change significantly. The change of microstructure leads to the change of refractive index n Of the main reasons, by optimizing the sputtering conditions can be prepared for phase-change optical disk high quality ZnS SiO2 dielectric film