New adhesive materials with improved thermal conductivity

There is increasing interest in the use of conductive polymeric adhesives as a replacement for soldering technology in electronic packaging applications. Relatively low cost, lower toxicity, reworkability and ease of processing make them an attractive alternative. To date, however, most conductive adhesives have certain critical limitations that inhibit their utility in many applications. We report on the development of new, low-temperature sintering adhesives that combine ease of processing of polymeric bonding materials with performance characteristics closer to solder. These new formulations incorporate novel fluxing polymeric resins in combination with a blend of metal alloy filler particles. During the cure process, the metal filler particles sinter together and are capable of forming "solder-like" metallurgical connections to a variety of metal surfaces resulting in lower and more stable thermal contact resistance values. These materials have both high electrical and thermal conductivity-closer to solder materials than most polymer-based materials but with the processing advantages of the best polymeric adhesives