Results of thermal characterisation based on the phase lag of photoacoustic
signal for front-rear surface illumination of porous silicon and nitrided
porous silicon membranes for gas sensing devices are presented. Thermal con
ductivity values in good agreement with literature values have been obtaine
d, confirming the usefulness and reliability of photothermal methods in the
investigation of new materials for sensors and microsystems. Preliminary r
esults of stokes-antistokes Raman investigations are also reported.