Solid State Refrigerator for Microchips

In this study the operating characteristics of a thermal management system consisting of a commercially available thermoelectric cooler integrated with a single phase microchannel heat sink is studied. The microchannel heat sink consists of trapezoidal microchannels of hydraulic diameter of 190 mu m and employs DI-water as the coolant. The effect of Reynolds number (Re), microchip power and thermoelectric power is studied. Reynolds number is varied between 24 and 100 for two different microchip powers of 5.33 W and 9.98 W and two different thermoelectric cooler voltage inputs of 8 V and 12 V. The performance is quantified in terms of the temperature difference and thermal resistance between the microchip and the inlet coolant temperature. These performance metrics are found to be better for the thermal management system with the thermoelectric cooler than one without it. Without powering the thermoelectric cooler the maximum temperature difference in the sytem and thermal resistance of the thermal management system is positive indicating that the microchip temperature is higher than the inlet temperature of the coolant. When the thermoelectric cooler is employed, the maximum temperature difference and thermal resistance is negative in certain cases indicating the microchip temperature is lower than the coolant inlet temperature. With increasing input power to the microchip, the thermal resistance increases even if the input voltage to the thermoelectric cooler is kept the same indicating that the thermal resistance of such systems is dependent on the power input and not simply constant as in systems without thermoelectric cooling.