Determination of thermophysical parameters of porous silicon using a photothermal technique

The effective thermophysical properties, diffusivity (α), effusivity (e), and thermal conductivity (k) have been measured by photoacoustic (PA) and photothermal interferometry (PTI) for silicon samples of varying porosities. The experimental results show a reduction in the thermal conductivity with increasing the porosity, by two orders of magnitude. The results obtained by PTI are compared to those obtained by the PA technique.