New Rapid Failure Analysis Techniques for Multilevel Metallization

Extract

Open interconnections on integrated circuits (ICs) are a serious and ubiquitous problem throughout the micro-electronics industry. The efforts to understand the mechanisms responsible for producing open interconnections and to develop analytical methods to localize them demonstrate the concern manufacturers have for this problem. Multiple layers of metallization not only increase the probability that an open conductor or via will occur because of the increased number of interconnections and vias but also increase the difficulty in localizing the site of the failure because upper layers may mask the failure site.

Rapid failure analysis of open-conductor defects is critical in new product development and reliability assessment of ICs where manufacturing and product development delays can cost millions of dollars a day. In this article, we briefly review some standard failure analysis approaches and then concentrate on new techniques to rapidly locate open-conductor defects that would have been difficult or impossible to identify using earlier methods. Each method is described in terms of the physics of signal generation, application, and advantages and disadvantages when compared to existing methods.