几种微构件材料的表面能及纳观黏附行为研究

对微机电系统（MEMS）中几种常用构件材料的表面能及其主要影响因素进行了探讨，并与材料表面的纳观黏附性能进行了分析比较.用Owens二液法计算出硅基材料的表面能在60—75 mJ/m²之间，它们之间总表面能的差异主要归结为表面能极性分量的差异，表面粗糙度的存在使表观表面能有所偏高.施加自组装分子膜后的表面能大为降低，粗糙度的存在可以使其表面能进一步减小.纳观黏附力和表面能之间有一定的对应关系.另外，在研究中发现表面粗糙度对纳观黏附行为的影响较小. 关键词： MEMS 表面能 纳观黏附 粗糙度

The surface energy and nano-adhesion behavior of some micro-component material in MEMS

This paper compares and discusses the surface energy and its related factors between different kinds of micro-component materials commonly used in MEMS, and analyzes the nano-adhesion behaviors of their surfaces. The results by the Owens method show that the surface energies of the silicon-based materials are between 60—75 mJ/m² and the presence of surface roughness would result in higher nominal surface energy when the contact angle is less than 90°. In contrast, the nominal surface energy would go much lower when the surface is rough with the coverage of a SAM film. There is a certain dependence of nano-adhesion on surface energy, and the effect of surface roughness on nano-adhesion can be neglected in the present study.