利用非平衡磁控溅射法制得厚度达到2.23μm的掺铬含氢类金刚石(Cr-DLC)碳膜。采用Raman光谱和XPS对制得的薄膜进行了结构和热稳定性等表征。结果表明：室温时,薄膜在1544 cm-1附近的Raman“G”峰归属于石墨结构中C—C键的伸缩振动,即E2g模式；而1367 cm-1附近的“D”峰归属于sp2碳环的“呼吸”振动模式,即A1g模式；计算得到薄膜sp3键的相对含量约为48at.%。加热至300℃,薄膜的Raman谱图与室温时相似,表明此温度段薄膜的结构稳定,未发生明显改变；至400℃时,ID/IG 值迅速增大,sp2键含量升高,表明此时DLC膜发生了明显的结构变化,开始发生石墨化。继续升温,膜中ID/IG 比率增加,“G”峰位向高波数方向位移,表明 sp 2/sp 3比率逐渐增大,薄膜石墨化程度加强,sp 2键的无序度逐渐降低,最终导致薄膜的摩擦系数和磨损率等逐渐增大,热稳定性逐渐降低。退火600℃时,ID/IG 值以及sp2键含量达到最大值,DLC薄膜失效。%Chromium doped amorphous hydrogenated carbon a-C∶H(Cr)films (2.23μm 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-1 was as-signed to C—C stretching vibration mode (E2g)in the Cr-DLC films,while the peak “D”near 1 350 cm-1 was 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.
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