中文摘要：

在30kW级直流电弧等离子体喷射化学气相沉积（Dc Arc Plasma Jet CVD）设备上，采用Ar-H2-CH4混合气体，通过调节甲烷浓度以及控制其他沉积参数，在Mo衬底上沉积出微/纳米复合自支撑金刚石膜。实验表明，当微米金刚石膜层沉积结束后，在随后的沉积中，随着甲烷浓度的增加，金刚石膜表面的晶粒大小是逐渐减小的。当甲烷浓度达到20％以上时，金刚石膜生长面晶粒呈现菜花状的小晶团，膜体侧面已经没有了粗大的柱状晶，而是呈现出光滑的断口，对该层进行拉曼谱分析显示，位于1145cm。附近有一定强度的散射峰出现。这说明所沉积的晶粒全部变为纳米级尺寸。

英文摘要：

Micro/nanocrystalline composite free-standing diamond films were deposited by 30kW DC arc plasma jet CVD method on molybdenum substrate with mixed fed gasses of argon,hydrogen and methane. Experimental results indicate that diamond crystalline grains were gradually diminished in succedent deposit with increasing the concentration of methane when diamond films of micro-layer deposit were finished. When the concentration of methane reached 20%, growth side of nano-layer of diamond films appeared canliflower-like diamond structure, and lateral side nano-layer of diamond films already had not been rough like columnar crystals and it had become smooth surface. We analyzed the lateral side of diamond films by laser-Raman spectrum. The results indicate that great intense scattering peak of nanocrystalline diamond at 1145cm^-1 in nano-layer. Therefore, conclusion could be drawn that these deposit grains became nanometer level size.