Effects of surface treatments on the performance of high thermal conductive die attach adhesives (DAAs)

Die attach adhesives (DAAs) do more than attach the die to the die pad, substrate, or cavity. They also provide thermal and/or electrical conductivity between the die and the package, essentially affecting the performance of the device while operating in the field. This study was carried out to investigate the effect of surface treatment on the electrical, thermal as well as mechanical properties of silver nanocomposite epoxy die attach adhesives. Several different types of surfactants, including thiol, silane-based coupling agent, siloxane, etc. were employed for silver filler functionalization and morphological studies have shown noticeable improvement in filler dispersion in the treated composite system compared to those untreated system. The properties of the DAAs and the interaction between the fillers and the polymers were carefully studied using a series of techniques including FTIR, SEM, Thermal conductivity testing system, etc, which showed that the surface treatment can enhance the thermal and electrical conductivity as well as the adhesion of the composite system.