金属互连结构的电迁移失效分析新算法

综合考虑了电子风、温度梯度、应力梯度和原子密度梯度四种电迁移驱动机制, 基于ANSYS软件平台和FORTRAN程序提出一种新的电迁移失效分析算法．通过ANSYS电－热－结构耦合分析获得模型的电流密度分布、温度分布和应力分布, 基于FORTRAN编写的原子密度重分布算法获得不同时刻的原子密度, 依据空洞生成和扩展失效准则进行电迁移动态空洞演化模拟并得到失效寿命．最后, SWEAT结构与CSP结构的应用算例验证了算法的精度．

A NEW ALGORITHM FOR ELECTROMIGRATION FAILURE ANALYSIS OF METAL INTERCONNECTS

This paper presents a new algorithm for electromigration (EM) failure analysis based on ANSYS and FORTRAN codes with considering the four driving forces,including electron wind force,temperature gradient,stress gradient,and atomic density gradient.The electric-thermal-structural coupled analysis is performed to obtain the current density distribution,the temperature distribution and stess distribution.EM atomic density redistribution algorithm is then developed using FORTRAN code to get atomic density distribution of different time.The dynamic simulation of EM void evolution is performed to get failure lifetime based on the criterion of void incubation and propagation.Finally,the comparisons of void generation through numerical example of SWEAT and CSP structure with the measurement results are conducted.