Influence of roughness on the detection of mechanical characteristics of low-k film by the surface acoustic waves

作     者：肖夏 陶冶 孙远 Xiao Xia;Tao Ye;Sun Yuan;School of Electronic and Information Engineering, Tianjin University

作者机构：School of Electronic and Information Engineering Tianjin University 

出 版 物：《Chinese Physics B》 (中国物理B（英文版）)

年 卷 期：2014年第23卷第10期

页      面：424-428页

核心收录：

学科分类：08[工学] 080501[工学-材料物理与化学] 0805[工学-材料科学与工程（可授工学、理学学位）] 0704[理学-天文学] 

基　　金：Project supported by the National Natural Science Foundation of China(Grant No.60876072) the Tianjin Research Program of Application Foundation and Advanced Technology,China(Grant No.10JCZDJC15500) 

主　　题：low-k film mechanical character detection rough surface rough interface surface acoustic wave 

摘      要：The surface acoustic wave （SAW） technique is a precise and nondestructive method to detect the mechanical charac- teristics of the thin low dielectric constant （low-k） film by matching the theoretical dispersion curve with the experimental dispersion curve. In this paper, the influence of sample roughness on the precision of SAW mechanical detection is inves- tigated in detail. Random roughness values at the surface of low-k film and at the interface between this low-k film and the substrate are obtained by the Monte Carlo method. The dispersive characteristic of SAW on the layered structure with rough surface and rough interface is modeled by numerical simulation of finite element method. The Young＇s moduli of the Black DiamondTM samples with different roughness values are determined by SAWs in the experiment. The results show that the influence of sample roughness is very small when the root-mean-square （RMS） of roughness is smaller than 50 nm and correlation length is smaller than 20 μm. This study indicates that the SAW technique is reliable and precise in the nondestructive mechanical detection for low-k films.