Effect of binders on the performance of copper sintering pastes

Copper sintering materials easily oxidize at high temperature. Therefore, functional binders capable of reducing copper oxides in-situ, have low boiling point, leave no unwanted residues and help realizing stable paste formulation are desired. Among all binders investigated in the study, a high boiling point, glycol based binder, provided the best reducing capability and highest shear strength followed by lower boiling point alcohol based binders. α-terpineol gave the best printability, however provided no protection against oxidation during sintering. Short chain alcohols reveal to have a better reducing effect and the sintering is improved for low temperature sintering, but they are too volatile to be reliable.