Investigation of epoxy molding compound with high adhesion on PD plated lead frames

With the rapid development of the advance integrated circuit (IC) packaging, adhesion between epoxy molding compound (EMC) and leadframes has been defined as one of the most key factors influencing the reliability of integrated circuit, especially with the packages with the Pd(PPF's) pated leadframes. The objective of this work was to study an epoxy molding compound with high adhesion on PPFs as well as good moldability. In this study three different types of epoxy resins (showed in Figure1), hardeners (showed in Figure2) and catalysts were investigated. It was found that epoxy resin B showed higher adhesion on Ag while epoxy resin A as the lowest. The composition of A/B/C as the epoxy resin exhibited higher adhesion on PPF. Hardener E and F exhibited high adhesion on PPF especially hardener E, and further on, hardener E possess lower DMA modulus and Tg than the other two hardener. While hardener F shows the highest adhesion on Ag. When using the composition E/F as hardener, the adhesion on PPF was as high as that hardener E. EMC with phosphorous catalyst in disclosed lower water absorption than that with imidazole one in. The latent phosphorous catalyst showed higher HH and higher adhesion on Ag and PPF that the other two catalysts.