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采用X射线衍射技术、电子背散射衍射技术和扫描电镜分别观察了不同甲烷浓度条件下沉积的CVD自支撑金刚石薄膜的宏观织构、微区晶界分布和表面形貌．研究了金刚石晶体{100}面和{111}面生长的晶体学过程．研究表明,{100}面通过吸附活性基团CH2 2-,而{111}面通过交替吸附活性基团CH3 -和CH3-后脱氢堆积碳原子．低甲烷浓度时,{111}面表面能低于{100}面,使{111}面生长略快于{100}面．甲烷浓度升高,动力学作用增强使{100}面生长明显快于{111}面,使金刚石薄膜产生{100}纤维织构;同时显露的{100}面平行于薄膜表面,竞争生长使位于晶体侧面的{111}面由于相互覆盖而减小,形成了不同于单晶体自由生长的薄膜表面形貌组织．
The macro-texture, micro-grain boundary distribution and surface morphology of CVD self-supporting diamond films deposited under different methane concentrations were observed by X-ray diffraction, electron backscatter diffraction and scanning electron microscope. The crystal growth of {100} plane and {111} plane of diamond crystal was studied. The study shows that the {100} plane adsorbs the active CH2 2- group, while the {111} plane accumulates carbon atoms by alternating adsorption of the active groups CH3 - and CH3-. At low methane concentrations, the {111} surface has a surface energy lower than the {100} plane, leaving the {111} plane to grow slightly faster than the {100} plane. The increase of methane concentration and the increase of kinetic effect make the {100} plane grow faster than the {111} plane and make the {100} fiber texture of the diamond film. Meanwhile, the exposed {100} plane is parallel to the surface of the film, The {111} planes on the side of the crystal decrease due to mutual coverage, forming a different microstructure of the film surface than the free growth of the single crystal.