Foley, S,Ryan, A,Martin, D,Mathewson, A;

1998

January

Microelectronics Reliability

A study of the influence of inter-metal dielectrics on electromigration performance

Validated

()

38

107

113

The relative electromigration performance of test structures with a common Ti/TiN-Al-1% Cu-TiN metallization scheme and with three different inter-metal-dielectric (IMD) layers is compared. Differences in lifetimes are observed which are attributable to the influences of the different IMD layers. The IMD layers in question are (a) polyimide, (b) a flexible inorganic dielectric layer, and (c) a rigid inorganic dielectric layer. A matrix of conventional electromigration tests has been carried put. The possible influence of stress migration is investigated and an explanation for the relative behaviour is proposed. (C) 1998 Published by Elsevier Science Ltd.