Experimental verification of prediction method for electromigration failure of polycrystalline lines

Abstract

A prediction method for electromigration failure in polycrystalline lines has been proposed using the governing parameter of electromigration damage, the atomic flux divergence (AFDgen), and the usefulness has been verified by experiment where various line shapes were treated under various operating conditions. In the prediction method, lifetime and failure site in a metal line have been predicted by numerical simulation of the processes of void initiation, its growth, to line failure. The simulation has predicted accurately the lifetime as well as the failure site of the metal line. In the verification, however, the metal lines treated had the same grain size, that is, the same microstructure. In this article, the prediction method for the electromigration failure of polycrystalline lines was verified in more detail, by comparing the prediction results of lifetime and failure site with the results of experiments using not only various shaped lines but also lines whose microstructures were different.