Temperature coefficient of resistance fluctuations during electromigration in Al lines

A simplified model is presented for the degradation of the conducting properties of Al stripes subjected to electromigration. Such a model has been used in order to investigate the role of grain boundaries in the behavior of the temperature coefficient of resistance (TCR). The results obtained by means of two dimensional simulations allow us to give a simple interpretation of the experimentally observed fluctuations of the TCR during electromigration.