SBIR Phase II: Reactive Mounting of Heat Sinks

This Small Business Innovation Research (SBIR) Phase II project introduces a new reactive joining process for mounting heat sinks onto chips, chip packages and substrates. The process uses reactive multi-layer foils as local heat sources for melting solder layers, and consequently bonding the components. The foils are a new class of nano-engineered materials, in which self-propagating exothermic reactions can be ignited at room temperature with a spark. The work will focus on reactive mounting of heat sinks onto server chips, an application that is in critical need of performance improvements. Two alternatives will be considered - the reactive mounting of a copper heat sink onto a metallized heat spreader that surrounds the chip, and reactive mounting of the heat sink directly onto a metallized chip. Significant improvements in heat conduction in microelectronic devices are needed as existing approaches such as adhesives, greases and epoxies suffer a number of limitations such as poor thermal conductivity, low mechanical strength and/or susceptibility to degradation. With the decrease in the size and the increase in speed of microelectronic devices, poor heat dissipation has started to limit device performance and applications and thus has become a critical issue. The worldwide market for thermal management in microelectronic devices is about $3.7 billion/year and high-end heat-sink mounting constitutes approximately 10% of this market.