Low Temperature Sintered Conductive Adhesives for use in the Packaging of High-Power Electronics

There is a growing need for improvement in the performance of thermally and electrically conductive polymeric adhesives used in electronic packaging. In particular, there are few polymeric materials that are suitable for replacing eutectic solder bondingin electronic devices used in high-temperature environments, such as the operating environment of high power wide bandgap electronic devices. Polymeric electrically conductive adhesives are usually comprised of silver flake dispersed in a polymer resin.The high level of silver flake required to impart the material with good electrical and thermal conductivity properties significantly impacts the long term reliability of the material, particularly when exposed to harsh, high-temperature environments. Wehave developed a low-temperature sintering adhesive that, with some modification, will address these performance issues. Our unique formulation incorporates a novel polymeric resin that can be tailored to cure rapidly over a varied temperature range. It issolvent-free and easily processed. Incorporation of a combination of suitable alloy powders in this resin formulation will also allow the preparation of composite adhesives capable of forming metallurgical connections to a variety of metal surfaces. Suchadhesives will have electrical and thermal conductivity properties similar to solder materials but with the processing advantages of current polymeric adhesives. There is an immediate need for adhesive materials with improved high temperature performancein a myriad of high volume consumer and defense products, particularly those materials that have improved thermal and/or electrical properties. The market today exceeds over $100 Million annually. This demand is increasing with the development of advancedhigh power electronics systems used for the processing and control of high-energy electrical systems.