A new organic hybrid-circuit based on an aramid non-woven type and sophisticated epoxy-resin combination

The concept of the organic hybrid circuit (OHC) has been embodied in the combination of PPDETA (non-woven type aramid) and ET-100 (a sophisticated epoxy resin with an aromatic amine added). This construction surpasses FR-4 (a combination of E glass and epoxy with dicyanediamide as a hardener). This structure shows the following advantages in terms of weight reduction and surface smoothness: heat endurance, especially in elevated Tg, and resistance to reflow-soldering heat; dimensional stabilities, especially reduced thermal expansion values; the removal of ionic contaminants and inhibition of metal migration; and machinability for compact piercing holes. The structure is of sufficiently high quality to be an ideal substrate for future surface-mount technology, able to replace not only FR-4, but also polyimide films and ceramic substrates.<>