目的 提高A向蓝宝石抛光速率。方法 分别采用诱导法和种子法制备了非球形和球形钴掺杂硅溶胶，并应用于A向蓝宝石的化学机械抛光。采用扫描电子显微镜（SEM）、电感偶合等离子体发射光谱仪（ICP）和X射线光电子能谱（XPS）检测产物颗粒的粒径及其分布、形貌、元素组成及存在状态等，采用CP-4抛光机对抛光速率进行验证，并用原子力显微镜测试抛光后的材料表面粗糙度，根据抛光后产物的XPS测试结果对抛光过程中的化学反应进行分析。结果 与纯硅溶胶相比，非球形钴掺杂硅溶胶抛光速率提高了37%，且表面粗糙度相近，而球形钴掺杂硅溶胶抛光速率却无明显优势。XPS结果显示，目前没有证据表明Co元素参与了化学反应。结论 非球形钴掺杂硅溶胶在A向蓝宝石抛光中起到了积极作用，归因于其形状优势而非Al2O3与Co之间的化学反应。

The work aims to improve polishing rate of A-plane sapphire (1120). Non-spherical and spherical Co-doped silica sol was prepared in induction method and seed induction method, respectively. The two products were applied in chemical mechanical polishing (CMP) of A-plane sapphire. Grain size, morphology, element composition and existential state of product particles were detected with scanning electron microscope (SEM), inductive coupled plasma (ICP) and X-ray photoelectron spectroscopy (XPS). Polishing rate was verified with CP-4 polisher. Surface roughness of polished materials was tested with atomic force microscope. Chemical reaction during polishing process was analyzed based upon XPS test results of polished products. Compared with pure silica sol, non-spherical Co-doped silica sol gave 37% higher polishing rate and similar surface roughness, while spherical Co-doped silica sol had no clear advantage in polishing rate, no evidence showed that Co element was involved in chemical reaction according to XPS results. The positive role of non-spherical Co-doped silica sol in A-plane sapphire polishing is attributed to its shape priority, but not chemical reaction between Al2O3 and Co.