Abstract
The effect of composition and curing temperatures on the thermal stability and adhesive strength of an Ag/epoxy conductive adhesive, currently being used in IC(integrated circuit) and PCB(printed circuit board) packaging, are investigated. DSC thermogram results indicate that the cure time is shrotened when curing agent is introduced in excess to the epoxy system. At the same curing temperature, higher degree of cure is obtained as the 4,4'-diaminodiphenyl sulfone(DDS) content is increased. This also influences the heat deflection temperatur and adhesive strength of the prepared epoxy compositions. From this investigation, the optimum epoxy composition is obtained at higher than 30 phr of DDS and curing temperatures above 150℃. Lastly, Ag flakes are introduced to raise the conductivity, and a diluent to reduce the viscosity of the adhesive. As a result, the electrical conductivity of Ag/epoxy system is increased about $10^{12}$ times higher than that of epoxy system.
