热丝法沉积金刚石膜工艺参数优化的微观机理与预测

Mechanisms and Optimization of Diamond Film Growth by Hot-Filament Chemical Vapor Deposition

弄清化学气相沉积金刚石膜的机理对优化工艺参数具有指导意义。在前期工作中,作者辨析了氢原子、甲基和乙炔在金刚石膜沉积中的作用。本文建立了两个微观指标,即甲基浓度和氢原子与乙炔浓度的比值,分别对应生长金刚石和刻蚀非金刚石碳。通过对CH和CHO反应气氛的模拟,讨论了这两个指标与灯丝温度、气源组成和气压的关系,并构建了含氧气氛生长金刚石的CHO三元相图。对热丝法沉积金刚石膜的工艺参数的优化选择进行了机理分析与预测,为工业化生产金刚石膜提供了参考。

Growth mechanisms of diamond film with hot filament chemical vapor deposition（CVD） were studied by analyzing the roles of atomic hydrogen,methyl and acetylene.Two micro criteria were established：one is the methyl concentration,and the other is the concentration ratio of atomic hydrogen and acetylene, corresponding to the growth of diamond film and the etching of non-diamond carbon, respectively. By simulating the gas-phase chemistry in C-H and C-H-O environment, we obtained the gas-phase equilibrium composition and the relationship between the two criteria mentioned above and various growth parameters, including the filament temperature, and the composition and partial pressures of the gas mixture. The C-H-O phase diagram for diamond film growth has been successfully constructed and the growth conditions were also discussed and optimized for industrial applications.