Porous silicon: Electonic properties

The electronic properties of porous silicon (p-Si) are studied by means of a supercell model with a tight-binding Hamiltonian and sp(3)s* atomic orbit als. The pores are modelled as empty columns digged in a crystalline silico n structure, passivated with hydrogens atoms. In this work, the band struct ure and the density of sates of p-Si are presented for different porosities . The results show that the energy gap increases with porosity, together wi th a shift of the conduction band minimum towards the Gamma point, as a con sequence of the quantum confinement.