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, high efficiency heat sink technology to support next generation high power, high reliability HEV power modules. The proposed project is focused on the development of a novel, low-cost integrated package and heat sink assembly for use in high-temperature power module packaging and thermal management. This integrated package and heat sink is enabled by a unique integrated ceramic-graphite-copper composite material technology and a highly effective compact heat transfer technology. The integrated assembly provides for electrical isolation of the power modules electronic components and circuitry, 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 primary research objectives of this project are the development of a low-cost unique integrated package and heat sink assembly and the establishment of the fabrication processes required to support its manufacture. There is a critical need for advanced packaging and active cooling solutions capable of meeting the thermal management requirements of emerging power module applications which include: (1) hybrid electric vehicle (HEV) power inverters and converters; (2) power converters for renewable energy systems (e.g., solar arrays, wind generators); and (3) power supplies for a wide variety of electronic systems (DC power supplies and inverters). Commercial Applications and Other Benefits. The unique integrated package and heat sink technology will provide lower thermal resistance and thus enable thermal management solutions that improve the operating range and efficiency for a wide variety of power electronic systems. The commercial applications of the proposed package and heat sink technology include silicon-based and silicon carbide-based power modules; RF power amplifiers used in communication systems; high brightness light emitting diodes used in solid state lighting and power electronics for harsh environment operation.