Detection of bond cratering defects under aluminum wedge bond using I–V characteristics and liquid crystal thermography

Abstract

This paper focuses on a failure analysis method on one common power IC failure encountered in the production lines. The new methodology utilizing liquid crystal thermography successfully shortens the total cycle time needed to detect the bond cratering defect and its root cause analysis. The decapsulated defective parts are subjected to suitable biasing current in liquid crystal thermography analysis to detect any hot spot emerging from the sides of the bonded aluminum wedge. This new method proves to be more effective and lower cost than the traditional decapsulation and delayering method.