Microhardness of porous silicon films and composites

Microhardness measurements have been performed on porous silicon (PSi) films. The dependence of the hardness on porosity, morphology and the underlying silicon substrate has been established. A model which determines the intrinsic film hardness has been developed and experimentally validated. The load dependence of hardness was measured as an index of the disorder in porous silicon. Hardness analysis also provided information on the nature of the PSi surface. Finally, several PSi-polymer nanocomposites have been fabricated and characterized. An improvement in hardness is observed, with no apparent change in the PL characteristics.