Lu Bao-qi, Xu Yao-xian, Shen Guang-yao, Ji Jiang-hua, Wang Lin-jun
Guang Pu Xue Yu Guang Pu Fen Xi. 2016 Nov;36(11):3568-71.
Chromium doped amorphous hydrogenated carbon a-C∶H(Cr) films (2.23 μm in thickness)have been successfully prepared with unbalanced magnetron sputtering technology(UBMS) in this paper. Raman spectrum and X-ray photoelectron spectroscopy (XPS) have been used to study the structure and thermal stability of the Chromium doped diamond-like carbon films (Cr-DLC). The results indicate that, at the room temperature, the Raman absorption peak “G” near 1 580 cm-1was assigned to C—C stretching vibration mode (E2g) in the Cr-DLC films, while the peak “D” near 1 350 cm-1was assigned to sp2 breathing vibration mode (A1g). The relative concentration of sp3 bond in the film is at 48%. When heated till 300 ℃, the Raman pattern of sample is similar to that of the sample at room temperature, indicating the structure of Cr-DLC film is stable. At 400 ℃, the ratio of ID/IG and the concentration of sp2 bond clearly increase, indicating the change of the structure in the Cr-DLC and the appearance of graphitization. With temperature going up, the rise of ID/IG ratio and the shift of the peak “G” to high wavenumber show that the rise of sp2/sp3 ratio, the intensity of graphitization, and the decline of the disorder of sp2 in the Cr-DLC films lead to the increase of the friction coefficient and wearing rate and the decline of the Cr-DLC thermal stability. When the it is up to 600 ℃, the ratio of ID/IG and the concentration of sp2 bond reach the max value while the Cr-DLC film loses its efficacy.
本文采用非平衡磁控溅射技术（UBMS）成功制备了厚度为2.23μm的掺铬非晶氢化碳a-C∶H（Cr）薄膜。利用拉曼光谱和X射线光电子能谱（XPS）研究了掺铬类金刚石碳膜（Cr-DLC）的结构和热稳定性。结果表明，室温下，Cr-DLC薄膜中1580cm-1附近的拉曼吸收峰“G”归属于C—C伸缩振动模式（E2g），而1350cm-1附近的峰“D”归属于sp2呼吸振动模式（A1g）。薄膜中sp3键的相对浓度为48%。加热至300℃时，样品的拉曼图谱与室温下的样品相似，表明Cr-DLC薄膜结构稳定。在400℃时，ID/IG比值和sp2键浓度明显增加，表明Cr-DLC结构发生变化并出现石墨化。随着温度升高，ID/IG比值升高以及峰“G”向高波数移动，表明Cr-DLC薄膜中sp2/sp3比值升高、石墨化程度增强以及sp2无序度降低，导致摩擦系数和磨损率增加以及Cr-DLC热稳定性下降。当温度达到600℃时，ID/IG比值和sp2键浓度达到最大值，此时Cr-DLC薄膜失效。
