Case Study: Failure Analysis of Thin Quad Flat Pack Package (TQFP) IC

This article describes systematic analysis of failure occurred in a Thin Quad Flat Pack Package (TQFP) integrated circuit. The electrical testing suggested that the device failure occurred inside of the device package. The sample was analyzed through Non-Destructive techniques of X-Ray imaging and Scanning Acoustic Microscope (SAM) to get insight into the internal structure and integrity of the sample in order to identify any anomalies. Even though the Nondestructive testing exhibited some early signs of the failure but was not enough for a conclusion. Subsequently, decapsulation of the sample was exercised to examine the internal structure of the die to unveil the crucial insights into the origin of problem. A specialized resistive (constant voltage) micro-probing was opted and carried out at pad level of the die which not only identified the internal circuit issues but also revealed the associated impact of the chemicals i.e., sulfuric and nitric acid on the die, introducing further layer of complexity in failure analysis methodologies. This comprehensive study provided valuable understanding of optimized methodologies for enhancing failure analysis process and highlighted the importance of mitigating the potential risks associated with the selection of chemical procedures in semiconductor investigations.