不同能级加速过滤电弧沉积四面体非晶碳膜的结构和性能

The microstructure and properties of tetrahedral amorphous carbon films deposited by filtered arc with accelerating at different energetic grades

采用过滤阴极真空电弧技术 ,通过施加 0— 2 0 0 0V衬底负偏压使沉积离子获得不同能级的入射能量 ,在单晶硅上制备了四面体非晶碳薄膜 .拉曼光谱分析表明 ,薄膜的结构为非晶sp3 骨架中镶嵌着平面关联长度小于 1nm的sp2 团簇 .原子力显微镜研究表明 :在低能级、富sp3 能量窗口和次高能级 ,薄膜中sp3 的含量越多 ,其表面就越光滑 ,应用sp3 浅注入生长机制能够圆满地解释薄膜表面形态与离子入射能量之间的关系 ;但在高能级 ,具有适当入射能量的离子对表面将起到溅射平滑作用 ,甚至可以得到比sp3 含量最高时均方根粗糙度更低的光滑表面 .纳米压入测试表明 ,高能 (-2 0 0 0V)沉积的四面体非晶碳膜具有比不加偏压时更高的硬度和杨氏模量 ,并具有比sp3

Tetrahedral amorphous carbon (ta_C) films were deposited on single crystallin e silicon by accelerating the species with different impinging energetic grades produced by s tatic_electricity pulse substrate bias from 0 to -2000?V. The microstructure of the ta_C films consist of amorphous sp 3 hybridization skeleton enchased with sp 2 clusters with sizes less than 1?nm by visible Raman measurement. At l ow energetic grade, sp 3-rich energetic window, and sub-high energetic grade, the more the content of sp 3 in the film, the smoother the surface of the f ilm. The relationship betw een the impinging energy of the species and the surface morphology can be illust rated perfectly in the light of subimplantation growth mechanism. Nevertheless, at high energetic grade, the impinging ions with appropriate energy and angle ca n sputter and smoothen the surface, even the roughness is lower than the surface of the films with the most sp 3. The hardness and Young's modulus of the films deposited at high energetic grade (-2000?V) are higher than those of the films prepare d on the floating conditions. At the same time, the critical scrat ching load of th e films deposited with the substrate bias of -2000?V is even larger than the o ne of the sp 3-rich films.