中文摘要：

研究了纳米通孔的分布对于表面波方法测量多孔低介电常数薄膜机械特性的影响，提出了用横观各向同性表征周期性多孔介质材料结构特性的表面波传播理论模型，给出了表面波在low-k薄膜／Si基底分层结构中的传播方程．通过数值算例揭示出表面波在不同传播方向的频散特性，以及low-k薄膜的弹性常数即杨氏模量E，E′和剪切模量G′对频散特性的影响．结果表明E′和G′在垂直于通孔的传播方向不能被测出．

英文摘要：

The influence of the distribution of nano-pores on the mechanical properties evaluation of porous low-k films by surface acoustic waves （SAW） is studied. A theoretical SAW propagation model is set up to characterize the periodic porous dielectrics by transversely isotropic symmetry. The theoretical deductions of SAW propagating in the low-k film/Si substrate layered structure are given in detail. The dispersive characteristics of SAW in differ- ent propagation directions and the effects of the Young＇s moduli E, E′ and shear modulus G′ of the films on these dispersive curves are found. Computational results show that E′ and G′ cannot be measured along the propagation direction that is perpendicular to the nano-pores＇ direction.