Measuring the Reliability of Technology Demonstrator Manufactured with Isotropic Electrically Conductive Adhesives

Electrically conductive adhesives are attracting interest as a possible replacement for solder in the assembly of some electronics equipment. Previous work had demonstrated assembly reliability on test assemblies, and investigated the effects of ageing regimes, component and PCB termination materials. In this phase of the work, a technology demonstrator – a currently offered commercial product (fire detector) – has been manufactured using ICA materials. Subsequently, these assemblies have been subjected to damp heat stressing to ascertain the likely field performance, which has been benchmarked against that of a conventionally soldered system. Whilst the reliability of the circuits assembled using the two ICA materials did not mirror that of the soldered circuits, their performance was encouraging, and certainly warrants further study. By optimising materials choice and process development, the CAs could find viable applications as a lead-free solder replacement. One ICA material produced joints whose reliability was close to that of the soldered joints- all the assemblies survived 1000 hours at 85%RH/85ºC, although two circuits require