氩离子轰击对四面体非晶碳膜内应力和摩擦系数影响的研究

利用磁过滤真空阴极电弧技术制备了sp³键大于80%的四面体非晶碳(ta-C)薄膜, 通过冷阴极离子源产生keV能量的氩离子轰击ta-C薄膜,研究了氩离子轰击能量对ta-C薄膜结构, 内应力以及耐磨性的影响.通过X射线光电子能谱和原子力显微镜研究了氩离子轰击对薄膜结构 与表面形貌的改性,研究表明,氩离子轰击诱导了ta-C薄膜中sp³键向sp²键的转化, 并且随着氩离子轰击能量的增大,薄膜中sp²键的含量逐渐增多, 薄膜内应力随着氩离子轰击能量的增大逐渐减小.氩离子轰击对薄膜的表面形貌有较大影响, 在薄膜表面形成刻蚀坑,并且改变了薄膜的表面粗糙度,随着氩离子轰击能量的增大, 薄膜的表面粗糙度也会逐渐增大.通过摩擦磨损仪的测试结果,氩离子轰击对薄膜的初始摩擦系数影响较大, 但是对薄膜的稳定摩擦系数影响较小,经过氩离子轰击前后的ta-C薄膜的摩擦系数为0.1左右, 并且具有优异的耐磨性.

The study on the stress and the friction coefficient of tetrahedral amorphous carbon films bombarded by energetic Ar ion

The ta-C films with sp³ bonds more than 80% in fraction are deposited by FCVA technique, and then they are bombarded by Ar ions. The composition and structures of the ta-C films before and after the bombardment of energetic Ar ions are analyzed by X-ray photoelectron spectroscopy. The surface morphology is investigated by AFM. The result shows that the bombardment of Ar ions induces the conversion of sp³ bond into sp² bond, and the fraction of sp² bonds increases with the energy of Ar ion increasing. The stress of the film decreases with the increase of the Ar ion energy. The RMS and etching pits on the surface of film increase with the increase of Ar ion bombarding energy.The friction test indicates that Ar ion bombardment has an important influence on initial friction coefficient, but just has little influence on steady state friction coefficient. The steady state friction coefficient of film keeps about 0.1, which shows a good antiwear property.