碳离子注入对硅片微动磨损性能的影响

Influence of Carbon Ion Implantation on Fretting Wear of Silicon Wafers

对单晶硅片〈111〉进行了注入剂量为2×10^(16) ions·cm^(-2)、注入能量分别为60 keV和80 keV的碳离子注入,采用X射线衍射仪研究了碳离子注入前后硅片晶体结构的变化,采用UMT-2型微动摩擦试验机进行了微动摩擦磨损试验,采用超高精度三维形貌仪测量了硅片的磨痕深度,采用S-3000N型扫描电子显微镜分析了硅片的磨损形貌及磨损机理。结果表明:碳离子注入改变了硅片的晶体结构,使晶体无序化;硅片的摩擦因数和磨痕深度均随着载荷、微动振幅的增加而增大;碳离子注入后硅片的减摩效果和抗磨性能得到明显改善,当载荷达到一定值后,随着时间的延长,碳离子注入层逐渐被磨破,摩擦因数迅速增大;注入能量为60 keV硅片的减摩抗磨性能较好;碳离子注入前后硅片的磨痕均呈椭圆形,注入后磨痕面积小且表面损伤程度较轻,磨损机制以磨粒磨损为主。

Single crystal silicon （111） wafer was implanted by carbon ions with the dose of 2×10^16ions·cm-2 and energy of 60 keV and 80 keV, respectively. Crystal structure changes of the silicon wafers before and after carbon ion （C＋ ）-implantation were observed by X-ray diffractometer. Then the fretting wear tests were performed on a UMT-2 micro-trihometer, and the wear depth, wear morphology and the wear mechanism were analyzed with high-accuracy 3D profiler and S-3000N scanning electron microscopy. The results show that crystal structure of the silicon vafers was changed by C＋-implantation which made the crystal disordered. The friction coefficient and wear depth of the silicon wafers increased with the increase of the load and fretting amplitude, and the friction-reducing effect and wear-resistance of the C＋- implantation silicon wafers were obviously improved. When the load reached a certain value, carbon ion implanted layer was worn out gradually as the prolongation time, the friction coefficient increased rapidly. And the silicon wafers with energy of 60 keV bad excellent friction-reducing and wear-resistance properties, The wear traces of the silicon wafers before and after C＋-implantation were similar to ellipse, the wear area was small and degree of damnificafion was mild after inplantafion. The main wear mechanism was abrasive wear.