Comparing migratory resistive short formation abilities of conductor systems applied in advanced interconnection systems

Various metallization types are applied in advanced high-density interconnection systems, pure metals as well as alloys, showing very different abilities for forming migration short circuit failures. There are two conventionally applied empirical possibilities for getting information or comparison about the migration behaviour of a conductor system, the water drop test, and the accelerated climatic tests, such as thermal humidity bias tests and the highly accelerated stress test. The results are generally uncertain showing large spreading and can only be interpreted with difficulties. A third method has also been developed and is presented in the paper for testing metallization systems based on a powerful technique, this is the very well-known cyclic voltammetry (CV) used in electroanalytical chemistry. The results indicate an effective method for making quick comparison between metallization systems in connection with their migration abilities. Moreover, the CV method enables a better understanding of the electrochemical processes that are the bases of the electrochemical migration. (C) 2001 Elsevier Science Ltd. All rights reserved.