种晶表面粗糙度及边部形态对MPCVD法生长单晶金刚石的影响

Influence of Seed Crystal Surface Roughness and Edge Appearance on Synthesizing Single Crystal Diamond by MPCVD

针对种晶的表面粗糙度和边部形态对MPCVD法生长金刚石单晶的影响进行了研究。结果表明,当样品表面粗糙度Ra值达到0.0066μm时,单晶金刚石沉积层已经可以呈现出较高的结晶质量。当表面粗糙度Ra值达到0.0162μm后,种晶的中心区域受到的影响较小,但种晶边缘区域的沉积却受到了较明显的影响。研究边部形态的实验中,在同一种晶的不同区域抛磨出45°边棱和90°边棱,生长后分别对这两个区域进行了拉曼光谱测试,测试结果表明,90°边棱处1332 cm-1金刚石本征峰的半高宽较小,沉积层质量较好,初步推测90°是更适合的种晶边棱角度。

The influence of seed crystal surface roughness and appearance on synthesizing single crystal diamond by MPCVD were studied. The results indicate that the sample with surface roughness Ra 0. 0066 μm has a high quality single crystal diamond layer. When the surface roughness Ra increased to 0. 0162 μm, the quality of the deposited diamond layer on the seed edges was influenced greater than on the seed center area. In order to study the influence of edge angle on the quality of the deposited diamond layer, the 45°edges and the 90° edges on the same seed before growth experiment were compared. Raman spectroscopy of the latter has shown the diamond 1332 cm^-1 peak with smaller FWHW so that the single crysta diamond layer above has higher quality. It＇s initially speculated that 90° edge is better for processing seed edges during the experiment.