Silver bearing conductors are thick film compositions for application onto ceramic substrates and dielectric compositions by screen printing. These sustrates are then fired in a conveyor belt furnace in an oxidizing atmosphere (air) to form interconnect tracks and pads in single- and multillayer microcircuits. Silver bearing conductor pads are normally used for passive SMT components attachement with low-temperature eutectic Sn/Pb solders or with conductive epoxy adhesives.
Many DuPont silver bearing conductors can be fired using short firing cycles (below 30 minutes) without affecting their performance. DuPont has also developed environmentally friendly silver bearing conductors (NIO-free and with PbO contents below 0.1%) to meet the stringent specifications on the use of restricted materials.
The performances of the different conductors vary in function of their metallurgy, metal ratio, and binder (oxides) contents, and of their organic vehicle, therefore, depending on the hybrid circuit requirements, the most cost-effective solution can be attained.