Two dimensional quantum net of heavily doped porous silicon

We produced and measured the thermoelectric(TE) properties of heavily doped p-type porous silicon(PS). Narrow 10 nm holes were formed through the anodic reaction of a p-type silicon wafer in hydrofluoric acid (HF) solution. We measured room temperature TE transport properties such as conductivity, Seebeck coefficient, thermal conductivity and thermal diffusivity perpendicular to the growth direction of nano-holes. Compared to initial silicon substrate we found that porous silicon has seven times lower electrical conductivity, three times larger Seebeck coefficient and four times lower thermal conductivity. The calculated figure-of-merit for porous silicon sample was about 3.5×10^-4 K^-1 which was five times larger than that of silicon