SiC过渡层制备温度对碳化硅/氟化类金刚石复合薄膜血液相容性的影响

Effects of preparation temperature of SiC intermediate layers on the hemocompatibility of SiC/F-DLC composite film

以316L不锈钢为基底,SiC晶体为靶材,Ar为源气体,采用磁控溅射法在不同温度下制备出系列SiC过渡层.然后以高纯石墨作靶,Ar和CHF_3为源气体,在同一工艺条件下再续镀一层氟化类金刚石(F-DLC)薄膜,形成SiC/F-DLC复合薄膜.研究表明,相比于F-DLC薄膜,复合薄膜的附着力显著增加,血液相容性明显改善.通过样品的拉曼和红外光谱分析了不同温度下制备的SiC过渡层以及复合薄膜结构的演变.结果表明,控制SiC过渡层制备温度可以有效调制过渡层中C=C键的比例以及—C—C—不饱和键的密度,复合薄膜中保留较高比例的芳香环式结构以及合适的F/C比是薄膜的血液相容性得以进一步改善的原因,SiC过渡层制备温度控制在500℃左右效果尤为明显.SiC薄膜和F-DLC两种薄膜的界面处形成一定比例的Si—C键和C=C键是导致复合薄膜附着力显著上升的直接原因.适当条件下在316L不锈钢和F-DLC薄膜之间增加SiC过渡层对于增强薄膜的附着力、改善其血液相容性是可行、有效的.

A series of SiC intermediate layers with different preparation temperatures is prepared by radio frequency magnetron sputtering on 316L stainless steel substrates by use of SiC crystal target and Argon as source gases. And then depositing fluorinated diamond-like carbon films （F-DLC） on a series of SiC intermediate layers under the same deposition condition with trifluromethane （CHF3） and Argon as source gases, and pure graphite as a target, a series of SiC/F-DLC composite films are obtained. The results show that the composite films have stronger adhesion and better hemocompatibility than that of the F-DLC films. The structure evolves with preparation temperatures of SiC intermediate layers and SiC/F-DLC composite films are studied by their Raman and Infrared transmission spectra. The results show that the proportion of C=C bonds and density of C-C unsaturated bonds in the SiC intermediate layers can be modulated by controlling the preparation temperature of SiC intermediate layers. The composite films have better hemocompatibility, especially with about 500 ℃ preparation temperature, may be attributed to holding higher proportion of aromatic ring structure and higher ratio of F/C in the composite films than the others. Formation of a considerable number of Si-C bonds and C=C bonds between SiC and F-DLC films may be the direct cause of strong adhesion. The addition of modest SiC intermediate layers between 316L stainless steel substrates and F-DLC films is feasible and effective to enhance films adhesion and improve film hemocompatibility.