磁控溅射Al靶功率对类金刚石薄膜结构和摩擦学性能的影响

Effect of Al Target Power of Magnetron Sputtering on the Structure and Tribological Properties of Diamond-like Carbon Films

本文采用中频磁控溅射金属Al靶,以CH4为反应气体,通过调整Al靶溅射功率,在p(100)单晶硅片和不锈钢基底上成功制备出不同Al含量的Al/a-C∶H纳米复合薄膜.并利用HR-TEM、XPS、纳米压痕仪和摩擦磨损试验机等手段分析和研究了Al/a-C∶H薄膜的结构、机械及摩擦学性能.结果表明:金属Al以纳米晶颗粒形式镶嵌在非晶碳网络中,使得所制备Al/a-C∶H薄膜呈现出典型的纳米晶/非晶复合结构;同时,Al掺杂促进了薄膜中sp2杂化碳形成,且有效地释放残余内应力.Al靶溅射功率为800 W时所制备的Al/a-C∶H薄膜具有结构致密、内应力低、硬度高的特性;在大气环境中,该薄膜与Si3N4陶瓷球干摩擦时显示出优越的摩擦学性能,其摩擦系数约为0.055,磨损率约为2.9×10-16m3/(N.m).

Aluminum/amorphous hydrogenated carbon（Al/a-C∶ H） nanocomposite thin films were deposited on silicon p（100） wafer and stainless steel substrates by magnetron sputtering of aluminum in an argon and methane atmosphere with different Al target power.The composition,microstructure,mechanical and tribological properties of composite films were systemically investigated by HR-TEM,XPS,nano-indenter and tribo-tester.The results showed that the Al nanocrystallites could be easily formed in the amorphous carbon matrix,the sp2 hybrid carbon was increased as the Al was embedded into the films,and Al-doping could relax the internal stress whilst keeping high hardness of as-deposited films.The film containing 4.7 % Al prepared by target power of 800 W exhibited a high hardness about 16.5 GPa,a low internal stress about 0.62 GPa,a low friction coefficient about 0.055 and a low wear rate about 2.9×10-16 m3/（N·m） in the ambient atmosphere.