Lightweight, Low-Cost, High-Performance Heat Sink for High-Power Electronics, Phase II

A key design limitation of many current electronic systems is heat rejection. As microchips become ever more densely packed with greater quantities of components, the amount of heat generated per unit area likewise increases rapidly. As the junctiontemperatures within an electronic component increase, the reliability and useful lifetime of the device decrease rapidly, even silicon carbide (SiC) components. In Phase I, Ultramet modeled, designed, fabricated, and tested lightweight, low-cost,high-performance heat sinks for actively cooled high-power SiC-based electronics. This new heat sink used open-cell silicon carbide foam as its key component, which functioned as a high thermal conductivity, high surface area cooling fin. SiC was chosendue to its high thermal conductivity, excellent corrosion resistance, and perfect thermal expansion match with SiC-based electronics. Heat transfer testing was performed both with and without foam, and the data showed that for a given heat flux and coolantflow rate, the foam-based heat sinks yielded junction temperatures 300-450¿C lower than those without foam. Similarly, for a given Reynolds number, the measured heat transfer coefficients were one to two orders of magnitude greater when foam was present.In Phase II, Ultramet proposes to further study the properties of these foams and work with leading RF component manufacturers and users to design, build, and test systems for use with ultrahigh-power SiC-based electronics. Commercial applications foradvanced heat sinks for electronic components include military and civilian radar, military, civil, and commercial satellites, manned and unmanned spacecraft, military and commercial aircraft, and mainframe and even personal computers, to name just a few.With the rapid growth of the electronics industry and the ever-increasing power density of integrated circuits, the need for advanced electronic heat sinks will only increase.