Performance of power dissipation on semiconductor module for different configuration of heat SINK with thermal pad

Abstract

An experimental and numerical investigation to assess the impact of the number of fin arrangements on heat dissipation and its subsequent influence on junction temperature under natural convection. The experimental phase incorporated a thermal pad with a thermal conductivity of 12 W/mK and an aluminum heat spreader measuring (17x16.5) mm. By utilizing the finite volume method (FVM), a numerical model was developed that closely resembles the experimental setup, with errors for temperature package and heat spreader measured at 0.08% and 4.49%, respectively. The analysis was carried out for five different numbers of fins, specifically s1=4fins, s2=6fins, s3=8fins, s4=10fins and s5=12fins. According to the numerical analysis, the increase in the number of fins from 4 to 12 led to a reduction in the average junction temperature from 79.11 °C to 75.97 °C. This denotes a decrease of 3.97% in the average junction temperature. The inclusion of fins on the heat spreader brought about an upsurge in conduction resistance from 55.77 °C/W to 56.19 °C/W, while the convective resistance observed a decline from 152.35 °C/W to 139.62 °C/W. By increasing the number of fins from 4 to 12, the Nusselt number experiences a monotonic decrease from 14.44 to 14.141 due to the reduction in fin-to-fin spacing. As a result, this would lead to a decrease in the natural convection flow. Hence, it was concluded that increasing number of fins beyond the optimal number of fins, signifying the point where thermal benefits become insignificant. The results of this study yield significant insights into the optimization and design of thermal solutions for semiconductor modules, ultimately providing a pathway to boost their operational efficiency and longevity in real-world applications.