High-resolution in-situ study of gold electromigration: test time reduction

The electromigration behaviour of a large set of gold interconnections is s tudied using the high-resolution in-situ measurement technique. First, init ial resistance drifts (DeltaR/R-0=0.1%) have been recorded on only one samp le for each stress level in a broad matrix of stress levels. Using these me asurements, the activation energy and the current exponent have been determ ined accurately. Second, failure times (DeltaR/R-0=10%) and values for sigm a have been obtained by applying higher stress levels on a population of te st lines. A combination of this two-step procedure with our high-resolution equipment yields a full characterisation of gold electromigration and a li fetime prediction with a significant higher accuracy and far less measureme nt time than using low resolution test systems. (C) 2001 Elsevier Science L td. All rights reserved.