脉冲负偏压对沉积类金刚石薄膜结构和摩擦性能的影响

Effect of pulsed bias on structure and tribological performance of diamond-like carbon films

在不同的基台脉冲负偏压下,利用微波-ECR等离子体化学气相沉积技术在单晶硅表面制备了类金刚石薄膜,利用傅立叶变换红外吸收光谱和原子力显微镜对薄膜的结构和形貌进行了表征,最后对薄膜的摩擦系数进行了测试。结果表明:制备的薄膜具有典型的含H类金刚石结构特征,薄膜致密均匀,表面粗糙度很小。随着负偏压的增大,红外光谱中2800–3000 cm-1波段的C-H伸缩振动吸收峰的强度先升高后降低,并在负偏压为200 V时达到最大;薄膜的摩擦系数而是先降低再升高,在负偏压为200 V时达到最小。

Diamond-like carbon films （DLC） were deposited on single crystalline silicon surface under different pulsed negative biases in an ECR （electron cyclotron resonance） plasma source. Chemical structure and morphology were characterized by Fourier transformation infrared spectroscopy （FT-IR） and atomic force microscopy （AFM）. Friction coefficient of the films was tested. The results show that the films, with smooth and dense morphology, were typical hydrogenated DLC with -CHn stretching in 2800-3000 cm^-1. By increasing the pulsed negative bias, the FT-IR peak intensity of C-H stretching vibration increased with the pulsed negative bias, reaching a maximum at 200 V, and then decreased. And friction coefficient of the films decreased with the pulsed negative bias, reaching a minimum at 200 V, and then increased.