Flame Synthesis of Diamond

本研究是火焰合成金刚石的基础性研究。研究了金刚石在低压、一维H2/O2/Ar- ch4和C2H2/O2/Ar火焰中的生长，并确定了生长的条件。实验的目的是提供一个已知化学性质的生长环境。生长实验将使用不会显著干扰火焰的细线微型衬底和设计用于在燃烧器和衬底之间的间隙中保持一维流场的大面积衬底进行。一维流场预测会导致均匀的大面积薄膜生长。火焰将被彻底表征。稳定的物质分布将使用石英探针和在线采样质谱仪进行测量，自由基分布（H, CH3， C， OH， CH和C2）和温度分布将使用激光诱导荧光，共振增强多光子电离和振动拉曼散射进行光学测量。测量将在有底物和没有底物的情况下进行，并将与具有详细动力学的一维反应流模型的预测进行比较。这些实验将是第一次在真正具有良好特征的环境中对钻石生长进行研究，并将产生有关钻石生长过程的重要信息。

The proposed research is a fundamental study of diamond synthesis in flames. Diamond growth in low-pressure, one- dimensional H2/O2/Ar-CH4 and C2H2/O2/Ar flames will be investigated and the conditions for which growth occurs will be determined. The experiments are designed to provide a well-characterized growth environment with known chemistry. Growth experiments will be carried out using both thin-wire micro-substrates which do not perturb the flame significantly and large-area substrates designed to maintain a one- dimensional flowfield in the gap between the burner and substrate. The one-dimensional flowfield is predicted to result in uniform large-area film growth. The flames will be thoroughly characterized. Stable species profiles will be measured using a quartz probe and an on-line sampling mass spectrometer, and radical profiles (H, CH3, C, OH, CH, and C2) and temperature profiles will be measured optically using laser-induced fluorescence, resonance-enhanced multiphoton ionization, and vibrational Raman scattering. The measurements will be made both with and without the substrate, and will be compared to the predictions of a one-dimensional reacting flow model with detailed kinetics. These experiments will be the first study of diamond growth in a truly well- characterized environment, and will yield significant information on the processes responsible for diamond growth.