1833 配線端部におけるエレクトロマイグレーション損傷の支配パラメータ  [in Japanese] A Governing Parameter of Electromigration Damage on Line Ends  [in Japanese]

Recently, a governing parameter for electromigration damage, (AFD)^*_<gen>, was identified and, utilizing the parameter, a prediction method of electromigration failure was developed for the passivated polycrystalline line of LSI. The parameter (AFD)^*_<gen> was formulated considering the divergence of atomic flux due to electromigration in grain boundary network, and the boundary condition on metal line ends was not taken into account. The failure prediction, therefore, was exclusively done for the metal line connected by electric-current input/output pads, not for the line connected by vias. It is known that there is threshold current density, below which no electromigration damage appears, in the line connected by vias. In this study, first, a governing parameter for electromigration damage on the ends of passivated polycrystalline line is expressed considering the boundary condition concerning the atomic diffusion on line ends. Next, the way to evaluate the threshold current density of the metal line with vias is shown using the governing parameter.