Effects of the liquid inlet temperature on the thermoelectric cooler performance in a liquid-TEC thermal system

The rapid growth of IC device density considerably intensified the importance of efficient thermal management systems in the semiconductor industry. Therefore, the attempt of removing higher heat associated with high performance IC devices is emerging as a valuable concern in the electronic technology. Thermoelectric cooler (TEC) technology integrated into a liquid cooling system has made evolutionary improvements in the thermal management technique. The aim of this study is to discuss the effect of the cooling fluid temperature on the thermal performance of a liquid-TEC system during a condition of time varying heat loads on the package. A thermal control unit (TCU), which consists of a liquid heat exchanger and TEC assembly, has been developed for IC device test sites. The TCU facilitates the control of package case temperature. An experimental approach was employed in order to qualify the TEC thermal performance. A matrix was developed from analyzing the effect of the water inlet temperature, flowing into the heat exchanger, on the package case temperature, package thermal load, TEC surface temperature and the TEC thermal resistance. It was found that adequate management of the package thermal loads is highly dependant on the liquid inlet temperature. At the same time, the system capability and characteristics can be reversed so the TCU can operate in a cold or a hot mode depending on the liquid inlet temperature.