The Thermal Conductivity of Porous Silicon

The thermal conductivity of porous silicon is measured as prepared and after oxidation. The measurement method uses thermal wave propagation in the porous film. We investigate three types of porous silicon: Nanoporous p-type silicon, nanoporous n-type silicon and mesoporous p + -type silicon. The nanoporous material shows a thermal conductivity in the region of 1.2 W/mK to 1.8 W/mK as prepared and after oxidation. This value is close to silicon oxide. The mesoporous material shows a high thermal conductivity of 80 W/mK as prepared which drops to 2.7 W/mK after oxidation.