Simulation on heat transfer of microchannels and thermal vias for high power electronic packages

The heat transfer characteristic of cooling microchannels and thermal vias integrated in low temperature co-fired ceramic (LTCC) multilayer electronic packaging substrate have been investigated by finite volume simulation method, including straight, spiral and I-shaped fractal microchannels. The width of microchannel is 200 microns and the height is about 186 microns. The side length of Cu thermal via is 0.1, 0.2, 0.5 and 1 mm with the amount of about 100. The water mass flow rate at the inlet was controlled at 45 ml/min and a high power chip of 100 W was supplied at the center of LTCC surface. The heat transfer behaviors were characterized by the decrease of maximum working temperature and temperature distribution of heating chip surface. It is found that the spiral microchannel with 1 mm thermal vias has the best cooling ability and the maximum temperature is reduced to 74.84°C. The adding of cu vias has great enhancement on the heat transfer by reducing the maximum temperature over 10%. The heat distribution of heating area is significantly improved due to the high speed of heat transfer from the chip to the cooling microchannels by high thermal conductive of Cu via.