DEVELOPMENT OF HIGH-THERMAL PERFORMANCE NANO-FLUIDS FOR COOLING OF ELECTRONIC SYSTEMS

Abstract

The nanofluids had showed super high thermal conductivity, which indicates a promising candidate as the cooling medium for high-performance microelectronic devices. In this work, the nanofluids were studied in terms of the making methods, thermal conductivity characterization, and applications into the micro-channel cooling systems for flip chip BGA package. The apparatus designed and fabricated based on the heat conduction model was used to measure the thermal conductivity of the nanofluids under steady state conditions. The suspended nanofluids were prepared by adopting the two- step method. The investigations on the thermal performance of the prepared nanofluids applied into the micro-channel cooling system in terms of the junction thermal resistance and pump power saving by using the cooling testing system would be expected to show that the thermal resistance would be decreased by nanofluids relative to the clear liquid water, while keeping the same pump power supply. Based on the mechanisms explored for the causes of the abnormal enhancement of the thermal conductivity of the nanofluids relative to the suspensions with large particle (at millimeter or even above, two novel models were developed to predict the thermal conductivity of the nanofluids including the proposed Modified HC model and Complex Nanoparticle model by Xue. Compared with the classic models, these two models have also taken into account of the particle's size effect besides the particle volume fraction and particle shape effects. These studies were verified by several experimental works.