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

在这项研究中。制备了氮化碳薄膜和氮化硼薄膜，并对其进行了表征。拉曼散射分析表明，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薄膜以类金刚石（DLC）结构为基本结构。所得膜的相对氮分数[N] / ([N]+[C])在各实验条件下均最大值为0.08。红外光谱分析表明，氮原子取代了碳原子或终止碳悬空键。离子束溅射法和磁控溅射法沉积的含氮碳膜的基本结构是DLC结构。所得膜的相对氮分数[N] / ([N] + [C])限制在0.08。这些结果有力地表明，所制备薄膜中的氮组成与薄膜的基本结构密切相关，与合成工艺无关。用随机共价网理论计算的氮的理论组成与实验结果吻合较好。因此，发现含氮碳膜中的氮组成受结构因素的限制。采用压痕蠕变试验研究了含氮碳薄膜纳米结构的变化。结果表明，含氮碳膜的黏性流动比无氮碳膜的黏性流动明显增强。此外，随着-C=N键的存在，黏性流动开始的临界力减小。这种纳米压痕蠕变技术是评价薄膜纳米结构变化的有效方法。我们还利用BCl_3和N_2气体用射频等离子体气相沉积法制备了氮化硼薄膜。由此产生的薄膜被发现是富含硼的成分。红外光谱发现B-N键形成sp^2键。用超低负荷微硬度压头测定所得膜的硬度约为20GPa。压痕蠕变试验测定的应变率敏感指数（m值）为0.005 ~ 0.008。这个值被发现类似于DLC或玻璃。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