Screen-printed copper superthick-films for power hybrids

So far, the thickness of screen-printed copper is not sufficient to drive large currents in high power modules. This paper describes a new fabrication process of copper superthick-films (300 μm), screen-printed on alumina substrates. Resistivity, peel strength, bonding strength and solderability measurements were performed for different firing conditions. As expected, the higher the firing temperature, the smaller the resistivity and the better the adhesion of the copper superthick-film. Moreover, the preliminary examination of a test vehicle using copper superthick-films shows a good thermomechanical behaviour, similar to that of DBC