Application of TOFSIMS for Contamination Issues in the Assembly World

Within the assembly world, problems related to package contamination, which stem from material sourcing and assembly process excursions, can impact product reliability. From the reliability perspective, it is essential to achieve integrity at all internal interfaces in the flip-chip, wire-bond, and novel mixed technology packages. In many instances, both organic and low-level ionic contaminants have resulted in interface delamination, metal migration, microcracking, etc., which leads to a premature failure of products either in reliability tests or in the field. Several examples of failure analysis relating to package contamination in the assembly world and the effectiveness of time-of-flight secondary ion mass spectroscopy in isolating and understanding failures are highlighted in this paper.