Porous silicon nanostructures under the action of microwave radiation

Abstract

The effects induced in structures containing nanocrystalline porous silicon layers under the action of microwave radiation have been investigated experimentally. The samples were made from boron doped p-type silicon wafers by etching in HF:ethanol=1:2 electrolyte and subsequent preparation of contacts. Electric conductivity of porous silicon samples and arising electromotive force (emf) were investigated under the action of microwave radiation. Activation nature of both effects was revealed. The model of hopping conductivity in the vicinity of Fermi level in the lattice of a porous silicon grid, considering fractal character of porous silicon skeleton have been applied to explain experimental results on conductivity. Two activation energies Eo'=0.45 eV and Eo”=0.07 eV were exhibited. The activation origin of emf was revealed in nanocrystalline porous silicon layers within the framework of carrier heating effect.