Journal of Vacuum Science & Technology B, Vol.23, No.6, 2384-2389, 2005
Temperature characteristics of stress-induced migration based on atom migration
Stress-induced migration is one of the problems associated with the reliability of metal interconnections in semiconductor devices. The physical model of stress-induced migration has been established as that of the migration of vacancies. Vacancies can be considered as holes among atoms constituting interconnections. To clarify the mechanism of stress-induced migration, an atomic migration model is more essential than the physical model. First, we present the stress-induced migration model based on atomic migration using simple calculations in detail. The key issue in this model is the change in elastic potential with atom migration, Second, the presented model is applied in simple cases for analyzing the stress relaxation time due to stress-induced migration. We found that the temperature characteristics of the stress relaxation time have sonic patterns depending on void surface stress, the stress in an interconnection, and void interval. These patterns reported concerning the interconnection lifetime due to stress-induced migration can be qualitatively explained by the presented model. (c) 2005 American Vacuum Society.