Geometry-Dependent Thermal Transport in Porous Silicon: A Computational Study of Pore Geometry and Porosity Effects

Abstract

This study investigates how pore geometry and porosity modulate the thermal conductivity and heat transfer characteristics of porous silicon. Leveraging OpenBTE—an open-source computational tool based on the Boltzmann Transport Equation (BTE)—the research analyzes three distinct pore geometries (circular, rectangular, and hexagonal) with porosity ranging from 5% to 45% in order to quantify their impact on phonon-mediated thermal transport.The results shown a clear dependence of thermal conductivity on pore shape and porosity. Rectangular pores showed the highest thermal conductivity, ranging from 64.4 W/(m·K) at 5% porosity to 26.7 W/(m·K) at 45%. Circular pores yielded intermediate thermal conductivity values, varying from 56.8 W/(m·K) at 5% to 9.5 W/(m·K) at 45. Hexagonal pores show the lowest thermal conductivity, ranging from 54.6 W/(m·K) to 7.2 W/(m·K). These insights demonstrate the critical role of pore architecture in tailoring heat dissipation pathways, providing actionable guidelines for engineering optimized pore networks. Experimental results advance the understanding of structure-property relationships in porous materials, enabling precise control over thermal performance for applications in thermoelectric, microelectronics, and energy-efficient systems.