单晶SiC基片的集群磁流变平面抛光加工

基于集群磁流变效应超光滑平面抛光理论及研制的试验装置，对单晶SiC基片进行了平面抛光试验研究。研究结果表明，金刚石磨料对单晶SiC基片具有较好的抛光效果；加工间隙在1.4mm以内抛光效果较好，30min抛光能使表面粗糙度值减小87%以上；随着加工时间的延长，表面粗糙度越来越小，加工30min时粗糙度减小率达到86.54%，继续延长加工时间，加工表面粗糙度趋向稳定。通过优化工艺参数对直径为50.8mm(2英寸)6H单晶SiC进行了集群磁流变平面抛光，并用原子力显微镜观察了试件加工前后的三维形貌和表面粗糙度，发现经过30min加工，表面粗糙度Ra从72.89nm减小至1.9nm，说明集群磁流变效应超光滑平面抛光用于抛光单晶SiC基片可行有效且效果显著。

Cluster Magnetorheological Effect Plane Polishing on SiC Single Crystal Slice

The super smooth plane polishing theory and its test equipment of the cluster magnetorheological effect were applied in the plane polishing process of SiC single crystal. The results show that diamond abrasive has good polishing effects for SiC single crystal slice. The working gap vaule within 1.4mm can get good machining results, which can get more than 87% of surface roughness reduction within 30min. Also, the surface roughness becomes smaller by extending the finishing time, 86.4% of the surface roughness reduction is attained by 30min, but extend the finishing time, surface roughness tends to be stable. At last,cluster magnetorheological effect test equipment was used to polish 2 inches 6H-SiC single crystal slice with above optimizing process parameters. By using atomic force microscopy to measure the three-dimensional morphology and surface roughness of the slice before and after processing,it is found that surface roughness Ra downs to 1.9nm from 72.89nm after 30min, which proves that using cluster magnetorheological effect plane polishing test equipment to polish SiC single crystal is feasible and the results are obvious.