Study of Moisture Characteristic of Epoxy Molding Compound and Hygroscopic Swelling Warpage Thru Bi-Material Sample

As microcircuits packaging development trend towards more miniaturizing, and more functionalities, the IC devices would be more susceptible to the humidity. Thus, the moisture related issues have been stressed recently. In this study, the full moisture characteristics of EMCs were investigated. Two sets of Csat (moisture concentration at saturation) values were obtained which determined by different dried weights, one is pre-bake weight, and the other one is post-bake weight (by JESD22-A120C). Besides, the CHS (coefficient of hygroscopic swelling) of EMCs were also examined. Furthermore, the hygroscopic swelling warpage measurement and finite element modelling by simple Bi-material specimen were performed to understand whether different dried weight methods affect the results in this work.