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在 0 .6keVAr+高剂量 (～ 10 2 2 /cm2 )辐照石墨表面 ,借助于高分辨透射电子显微镜 (HRTEM ) ,发现有六方金刚石纳米晶产生 .它们的平均直径介于 1— 5 0nm之间 ,而且晶粒个数约随其直径的增大而直线减少 .有趣的是 ,晶粒具有两种结构模式 :直径小于 10nm的晶粒为单晶结构 ,而直径大于 10nm的为多晶结构 .基于受离子轰击过程特点制约的六方金刚石晶粒成核和成长观点 ,讨论了这种双重结构的形成性质
At 0.6 keVr + high dose (~ 10 2 2 / cm 2) irradiated graphite surfaces, hexagonal diamond nanocrystals were found with the help of high resolution transmission electron microscopy (HRTEM). Their average diameter ranged from 1 to 500 nm , And the number of grains decreases linearly with the increase of their diameter.It is interesting that the grains have two structural modes: the grains with the diameter of less than 10nm are single crystal structure, while the diameter larger than 10nm is the polycrystalline structure. Based on the nucleation and growth of hexagonal diamond grains controlled by the characteristics of ion bombardment, the formation properties of the dual structure are discussed