Stress evolution and drift kinetics in confined metal lines
A model describing stresses and vacancy system evolution and also drift phenomena caused by electromigration (EM) in metal interconnectors has been proposed. It is shown that the drift kinetics has three main stages, i.e., induction period, quasi-stationary and stationary state. Induction period is characterised by an increase in the stress at the ends of a conductor; drift is absent. Drift begins when the yield limit is achieved at the cathode edge of the conductor. Drift rate increases, reaches a maximum and then decreases down to the stationary value. Characteristic times for all the stages are determined. Also, the effect of the length of the conductor on drift kinetics is analysed.
stress evolution drift kinetics electromigration