Characterization of new ultra-hardness material-carbon nitride and rhombohedral boron nitride syntesized using electron cycrotron resonance plasma

本研究制备了氮化碳薄膜和氮化硼薄膜，并对其进行了表征，以研究这些薄膜的新功能。拉曼散射分析表明，使用电子回旋共振（ECR）等离子体增强化学气相沉积（CVD）装置沉积的非晶氮化碳膜具有作为基本结构的类金刚石碳（DLC）结构。所得薄膜的相对氮分数[N] /（[N]+[C]）在每个实验条件下均为0.08作为最大值。红外光谱分析表明，氮原子取代了碳原子或终止了碳悬挂键。使用离子束溅射法或磁控溅射法沉积的含氮碳膜具有DLC结构作为基本结构。所得膜的相对氮分数[N] /（[N] + [C]）限制为0.08的值。这些结果有力地表明，所得薄膜中的氮成分是静止的， ...更多信息 与毡的基本结构相吻合，不依赖于合成过程。用无规共价网络理论计算的氮分子的理论组成与实验结果符合较好。因此，含氮碳膜中氮的组成受结构因素的制约，本文通过压痕蠕变实验研究了含氮碳膜的纳米结构变化。结果发现，含氮碳膜的粘性流动相比，没有氮的膜得到促进。此外，粘流开始的临界力随着-C=N键的存在而降低。我们还用射频等离子体化学气相沉积法，以BCl_3和N_2为原料制备了氮化硼薄膜。发现所得膜是富硼组合物。红外光谱分析表明B-N键形成sp^2键。用超低载荷显微硬度计测得薄膜的硬度约为20 GPa。压痕蠕变试验测得的应变速率敏感指数m值为0.005 ~ 0.008。发现该值与DLC或玻璃相似。少

In this study. carbon nitride films and boron nitride films werr produced and characteized to investigate new function of these films. Raman scattering analysis reveals that the amorphous carbon nitride films deposited using an electron cycrotron resonancc (ECR) plasma enhanced chemical vapor deposition (CVD) apparatus had dianond-like carbon (DLC) structure as a fundamental structure. The relative nitrogen fraction [N] / ([N]+[C]) of the resulting films were 0.08 as a macimum value at every experimental conditions. IR spectra analysis reveals that nitrtogen atoms were substituted for carbon atoms or terminated carbon dangling bonds. Nitrogen containing carbon films deposited using an ion beam sputtering method or a magnetron sputtering method had DLC structure as the fundamental structure. The relative nitrogen fraction [N] / ([N] + [C]) of the resulting films were restricted to valus of 0.08. These results strongly suggest that the nirogen composition in the resulting films were rest … More ricted with fundamental structure of the felms and independent upon synthetic process. Theoretical composition of nirtogen calculated using the random covalent network theory was good agreement with experimental resuits. Therefore nitrogen composition in nitrogen-containing carbon films were found to be restricted to structrual factor.An indentation creep test has been performed to investigate the namo-structure changing of nitrogen-containing carbon films. It was found that viscous flow of the nitrogen-containing carbon films were promoted as compared with the films without nitrogen. Furthermore the critical force of the viscous flow beginning was decreased with the presence of the -C=N bond. This nano-indentation creep technique was found to be the effective technique in evaluation of nano-structure changing of the films.We have also produced boron nitride films using an r.f.plasma CVD method from BCl_3 and N_2 gas. Resulting films were found to be boron-rich composition. B-N bonds were found to form sp^2 bond from IR spectra. Hardness of the resulting films determined by an ultralow-load micro-hardness indenter were about 20GPa. The strain rate sensitivity exponent (m-value) detemined by an indentation creep test was 0.005-0.008. This value was found to be similar to DLC or glass. Less