Electrical conductivity mechanisms in porous silicon

Abstract

In the present paper the peculiarities of conductivity of porous silicon are studied. For the first time an attempt is made to describe analytically the dependence of porous silicon conductivity on material porosity. It is found that the conductivity is mainly crystalline for porosities much lower than the percolation threshold at 57%, while a fractal behavior is observed at porosities near percolation threshold. For higher values of porosities, the conductivity turns smoothly into a quasi-one-dimensional hopping. The reduction of the electrical current flow channels dimension from 3 to 1 for lower temperatures, described by the Mott law for amorphous semiconductors, occurs in porous silicon with increasing porosity.

Influence of polarized bias and porous silicon morphology on the electrical behavior of Au-porous silicon contacts

“…The effect of temperature on the current density-voltage (I-V) characteristic of metal contacts on PS films was observed in experiments (Pazebutas et al, 1995;Chen et al, 1994a;1994b;Remaki et al, 2003;Aroutiounian and Ghulinyan, 2003;Balagurov et al, 2001). Those authors proposed different mechanisms.…”

Pore-size dependence of the thermal conductivity of porous silicon: A phonon hydrodynamic approach

“…2,11 A detailed knowledge of this dependence may have valuable practical consequences. Since increasing porosity also deteriorates the electron transport properties, 20,21 being able to reduce thermal conductivity by several alternative procedures opens a wider range of possibilities, which may be of interest in thermoelectric applications.…”

Porous silicon gas sensors

“…An interaction with dangling bond states may also lead to adsorbate-induced conductance changes. Peculiarities of the conductivity in PSi have been studied theoretically, for example by Aroutiounian and Ghulinyan (2003). An analytical study of the dependence of PSi conductivity on porosity has been made.…”