中文摘要：

激光激发超声表面波法（LSAWs）是一种无损检测技术,其理论依据为表面波在分层材料中传播时发生频散.在检测超薄low-k薄膜材料机械特性时,LSAWs方法在准确性、快速等方面比传统的纳米压痕法具有明显优势.对大量的实验数据进行了细致分析,得到了频率低于200 MHz的表面波频散曲线的特殊规律,并在此基础上建立了一种基于二分法的快速查找算法,实现了理论与实验频散曲线的快速匹配.超声表面波技术对超薄low-k膜层材料的弹性模量进行在线检测时,采用快速匹配算法可以显著提高检测速度.

英文摘要：

Laser-generated surface acoustic waves （LSAWs）method is a nondestructive detection technology, which is based on the dispersion property of LSAWs during the waves propagating in the layered structure materials. Compared with traditional nano-indentation method, LSAWs approach is accurate and fast, especially very suitable to determine the mechanical properties of fragile ultra-thin low dielectric （low-k） film. A particular feature on the SAWs dispersion curve with frequency below 200 MHz was obtained through analyzing a large number of experimental data. A fast matching algorithm for mechanical property determination based on the dichotomy was developed to match the theoretical dispersion curve with the experimental one effectively. The measuring speed of SAWs technology for Young＇s modulus detection for low-k films is significantly enhanced by applying the proposed fast matching algorithm.