ELECTROMIGRATION IN AL BASED STRIPES - LOW-FREQUENCY NOISE MEASUREMENTS AND MTF TESTS

Traditional [Median time to Failure (MTF)] and non traditional (Noise measurements) techniques have been used to characterize four types of Al based samples. Relatively weak stress conditions, which cause negli gible modifications to the sample structure, have been used for noise measurements, whereas more accelerated stress conditions have been use d for lifetime tests. Quite different results have been obtained by th e two types of characterization. In fact, the experimental data showed that the noise measurements are useful to evaluate the activation ene rgy at relatively weak stress conditions, but cannot be used to forese e the behavior of the samples at strongly accelerated stress condition s. This is particularly true in the case of samples containing copper which probably undergo significant microstructural modifications as th e temperature goes up. Moreover, the results of a simple computer simu lation which show the dramatic effect on the Time to Failure of the sp reading of the values of the thermal resistance of the samples are rep orted. Copyright (C) 1996 Elsevier Science Ltd.