RESISTANCE NOISE MEASUREMENT - A BETTER DIAGNOSTIC-TOOL TO DETECT STRESS AND CURRENT-INDUCED DEGRADATION

Mechanical stress and current-induced degradation can provoke holes an d kinks in thin conducting films, resulting in a local increase in cur rent density around these failures. This type of degradation resulting in holes or kinks in thin film resistances has been studied. A model describing the increase in 1/fnoise and resistance due to a local curr ent density increase around failures is presented here. Our calculatio ns are in agreement with experimental results obtained on carbon films damaged on purpose. It is shown quantitatively that 1/f noise is a mo re sensitive parameter than resistance measurements only. Noise measur ement can be used as a fast and non-destructive technique for reliabil ity testing of LSI Al interconnects and thin-film resistors on the con dition that samples effectively contain not more than 10(13) free carr iers. Copyright (C) 1996 Elsevier Science Ltd