国外刊物论文译文选登(1)
发布时间:2011/10/13 阅读:28301
In the present work the facts of ballas diamond deposition will be summarized and correlated with the described nano-crystalline diamond. |
本文对半刚石沉积的实际情况进行了综述,并将它们与所述纳米晶金刚石联系起来。 |
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2. Low-pressure diamond deposition | 2. 低压金刚石沉积 | |
By means of the low-pressure CVD synthesis various diamond morphologies(e.g. facetted, ballas, graphitic) can be synthesized by varying the deposition parameters(Fig. 1). | 低压CVD合成法通过改变沉积参数能够合成不同形貌的金刚石(例如,多面金刚石,半刚石,石墨金刚石)(图1)。 | |
The main parameter for diamond growth is the atomic hydrogen concentration, which is mainly influenced by the power density of the activation method. For diamond growth itself the atomic hydrogen has to be present during depositon on the surface, where he determines the crystal quality obtained during the low-pressure diamond synthesis. Due to recombination effects also other parameters, such as the distance from atomic hydrogen source to the substrate, gas pressure, gas velocity and the overall gas phase composition(such as the H/C or H/C/O ratio) influence the amount of atomic hydrogen on the surface. Foreign gases act mostly as “impurities”, and are detrimental for the growth of faceted crystals. Last but not least the substrate surface temperature influences growth of the diamond due to surface diffusion and recombination effects. | 原子态氢浓度是金刚石长大的主要参数,它主要受到活化方法的能量密度的影响。对于金刚石本身的生长,原子态氢要出现在表面沉积过程中,因为这时它能决定在 低压金刚石合成中获得的晶体质量。由于重新组合的缘故,其它的参数如氢原子源到基体的距离、气压、气体速度和整个气相成分(如H与C或H、C、O之比)会 影响表面原子态氢的数量。夹杂气体多半为“杂质”,不利于多面晶体的长大。最后但并不是最不重要的是,由于表面扩散和重新组合的缘故,基体表面温度对金刚 石的生长也有影响。 |