The Growth Mechanism of Diamond Crystals in Acetylene Flames
The Growth Mechanism of Diamond Crystals in Acetylene Flames
复制标题
乙炔火焰中金刚石晶体的生长机理
DOI：
10.1143/jjap.29.1552
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发表时间：
1990
影响因子：
1.5
通讯作者：
Y. Hirose
中科院分区：
文献类型：
--
作者：
Y. Matsui;H. Yabe;Y. Hirose
为了探讨金刚石在乙炔火焰中的生长机理，进行了数值计算，包括水冷衬底附近边界层中的气相反应和生长晶体上的整体表面反应。结果表明，CH4和C2H4等稳定物种在层内迅速生成，然后根据反应的快速部分平衡CH4+H\右左向左CH3+H2生成甲基自由基。计算的CH4浓度与测量的CH4浓度的比较表明，吸附在金刚石表面的C-自由基被H原子刻蚀形成CH4，尽管表面反应对气体浓度没有显著影响。生长速率对衬底温度和C2H2/O2比的依赖关系可用CH3-前体模型解释。
To discuss the diamond growth mechanism in acetylene flames, numerical calculations are carried out, including both gaseous reactions in the boundary layer near a water-cooled substrate and overall surface reactions on a growing crystal. It is shown that stable species such as CH4 and C2H4 are rapidly produced in the layer, followed by the methyl radical formation according to the fast partial equilibrium of the reaction, CH4+H\rightleftarrowsCH3+H2. The comparison between the calculated and the measured CH4 concentrations upon the substrate has revealed that C-radicals adsorbed on the diamond surface are etched by H-atoms to form CH4, though the surface reactions do not have a significant effect on the gaseous concentrations. The dependences of the growth rate both on the substrate temperature and on the C2H2/O2 ratio are shown to be explainable by the CH3-precursor model.