Effect of cooling fluids on high frequency electric and magnetic fields in microelectronic systems with integrated TSVs

Abstract

A fully 3D conjugate numerical analysis was performed to reveal the effects of air, R134a refrigerant and water on electromagnetic fields of electronic cooling designs made of arrays of micro pin-fins with integrated Through-Silicon-Vias (TSVs). The integrated TSV cooling configuration included 8 cylindrical TSVs with 150 µm diameter each and 200 µm height. The external dimensions of the silicon substrate were 900×700×280 µm. Each TSV encapsulated four equally spaced copper vias each having a diameter of 40 µm. The impacts of the presence of the stationary cooling fluids without heat transfer on TSVs electric and magnetic fields were examined for five different frequencies; 100 MHz, 500 MHz, 1 GHz, 5 GHz and 10 GHz. Then, separately, the effects of moving cooling water with temperature-dependent physical properties were studied while exposing the cooled micro pin-fin array to a uniform heat flux of 500 W cm−2. For the case of stagnant and moving cooling fluids it was found that water influences the electric field twice as much as either R134a or air and that this influence decreases only negligibly with the increase in frequency of the electric current passing through the TSVs. The influence of the presence of the stagnant and moving cooling fluids on the magnetic field is orders of magnitude smaller and reduces rapidly with the increased frequency.