Low-Cost Integrated Package and Heat Sink for High-Temperature Power Modules

There is a growing demand for power electronics that can operate under the high temperature and high power conditions that will be encountered in Hybrid Electric Vehicles (HEVs). As the coolant temperature used to dissipate heat from electronics increases, the operation of power semiconductor devices becomes severely limited in order that the safe operating temperature limit of the semiconductors not be exceeded. There is a need for low-cost, integrated package-heat sink technology to support next generation high power, high reliability HEV power modules. The Phase I effort has established a novel, low-cost integrated package-heat sink technology for use in high-temperature power module packaging and thermal management. This integrated package-heat sink technology is enabled by a unique copper-ceramic-graphite-copper substrate technology and a highly effective compact heat transfer technology. The integrated assembly provides for electrical isolation of the semiconductor and electrical components, and minimizes the thermal resistance between the power semiconductor devices and the heat sink coolant. Further, the assembly provides for the minimization of the coefficient of thermal expansion. (CTE) mismatch between the different material layers of the assembly in order to minimize thermal stresses resulting from cyclic power and temperature operation key to achieving a reliable product with a long life. The Phase II effort is focused on the development and demonstration of products based upon the technology. The goal of the project is (1) the final design of the integrated package-heat sink assembly and (2) the establishment of the fabrication processes required to support its low-cost manufacture. Commercial Applications and Other Benefits: The unique integrated package-heat sink technology provides lower thermal resistance and thus enables thermal management solutions that improve the operating range and efficiency for a wide variety of silicon-based and silicon carbide-based power electronic systems. The commercial applications of the proposed package-heat sink technology include: (1) HEV power modules; (2) power converters for renewable energy systems (e.g., solar arrays, wind generators); (3) power amplifiers used in communication systems; and (5) high brightness light emitting diodes for medical and industrial applications.