热铁盘法抛光CVD金刚石的微观表面研究

Study on micro surfaces of CVD diamond polished by hot metal plate

用原子力显微镜对热铁盘法抛光CVD金刚石达到R_a0.016μm的表面进行观察。在微观表面重现的基础上,对不同方向的表面粗糙度进行探测。发现抛光后的金刚石表面的粗糙度呈现出一定的方向性,最大粗糙度和最小粗糙度方向,两个方向相互垂直。三维形貌图显示,金刚石表面存在较少数量的由点到凸峰,且较大凸峰的高度在50～60 nm之间,是较小凸峰高度的2～3倍。影响表面粗糙度值的因素不仅有表面凸峰的高度,还应考虑表面凸峰的数量和方向性。这种表面特征与抛光时采用的直压式运动方式有着直接联系。

CVD diamond surfaces polished by hot matal plate to Rα 0. 016 μm were studied by using atomic force microscope （AFM）. On the basis of micro surfaces redrawing, the surfaces were profiled through different directions. The results show that the roughness degrees obey certain rules related with the direction, and the direction of maximum roughness is vertical to that of the minimum one. 3D topographies also show that there are a small amount of summits on the surface. The high summits is about 2 - 3 times higher than the low summits. The roughness degree of the surface is not only affected by the height of the summits, but also by the amount and directions of the summits. The characteristics of polished surfaces is directly related with the mode of direct pressure in the polishing process.