530 Analytical research for plastic strain localization in Au Micro-interconection

Abstract

The purpose of this study is to investigate the plastic strain localization in a gold (Au) micro-interconnection, which connects through-hole electrodes in a three-dimensional chip stacking LSI. The micro-interconnection is composed of several tens of grains, hence the inhomogeneity of mechanical property due to the grains brings about strain distribution. An elastic-plastic finite element method analysis for a polycrystalline analytical model shows that the high strain region exists near the center of the micro-interconnection and it expands as the deformation goes on. By statistical evaluation of plural models composed of grains with different shape and crystallographic orientation, it is clarified that the variations of the size and the intensity of the high strain region approximately have normal distribution.