论文部分内容阅读
反应烧结碳化硅(RB-SiC)是一种性能良好的反射镜镜胚材料,但其固有的一些缺陷导致未经特殊处理无法获得光滑的光学表面。使用X射线衍射(XRD)测试了反应烧结碳化硅试片的晶体结构,结果表明其主要成分为多晶态碳化硅和多晶态硅。扫描电子显微镜和原子力显微镜的测试结果指出镜胚表面残留的孔洞及抛光形成的台阶是造成散射降低光学性能的原因。通过等离子辅助沉积技术在反应烧结碳化硅表面镀制了一层硅改性层,消除了缺陷,再精细抛光硅改性层,获得了质量良好的光学表面。自行搭建的总积分散射仪对镀制硅改性层前后的反应烧结碳化硅表面进行了测量,总积分散射分别为9.37%和1.84%,改性后数值降低到改性前的1/5。反应烧结碳化硅反射镜光学性能得到了明显提高,接近抛光良好的K9玻璃。
Reactive Sintered Silicon Carbide (RB-SiC) is a well-behaved mirror-like substrate material, but inherent defects have resulted in a smooth optical surface that can not be obtained without special handling. The crystal structure of reactive sintered silicon carbide test piece was tested by X-ray diffraction (XRD). The results showed that its main components were polycrystalline silicon carbide and polycrystalline silicon. The results of scanning electron microscopy (SEM) and atomic force microscopy (AFM) indicate that the remaining holes on the surface of the mirror and the steps formed by polishing are the causes of the scattering reducing the optical performance. Plasma-assisted deposition technique was used to deposit a layer of silicon-modified layer on the surface of reaction-sintered silicon carbide to eliminate the defects. Then the silicon-modified layer was finely polished to obtain a good quality optical surface. The self-built total-integrating scatterometer measured the surface of the reactively-sintered silicon carbide before and after the silicon-modified layer was plated, the total integral scattering was 9.37% and 1.84% respectively, and the value after modification was reduced to 1/5 before the modification. The optical properties of the reactively sintered silicon carbide mirrors have been significantly improved, approaching the polished K9 glass.