Non-destructive electrical fault isolation (FI) techniques such as emission- and laser-based techniques have been utilized widely for chip-level failure analysis (FA). However, these techniques by themselves can sometimes be inadequate for certain failure modes. In this paper, we present six FA case studies using Time-Domain Reflectometry (Electro-optical terahertz pulse reflectometry) in combination with the traditional FI techniques.

X-ray imaging for both Failure Analysis and In-line Inspection has been utilized widely in the semiconductor industry, especially for surface mount device applications. During the investigation of total ionizing dose (TID) induced degradation of logic ICs with bulk FinFET technology, we observed that the degradation is mainly in the form of an increase in I/O leakage and IDDQ . Using filters during radiation was shown to impact TID. Failure Analysis was performed to localize the excessive current in both I/O leakage and IDDQ.

We investigated and demonstrated the advantages and limitations of several optical methodologies as valuable silicon failure analysis techniques, and how they could be used in a complementary manner to assist in shortening the diagnostic time.