Electrical behaviour of aluminium-porous silicon junctions

摘要: In order to analyse the electrical behaviour of aluminium-porous silicon junctions, we studied current-voltage and temperature I(V, T) characteristics a series having typical porosity 45% layer thickness ranging from 2 30 jam. Under forward bias, current can be fitted by law I=I s (exp(q(V-R I)/nkT)), with R serial resistance few kiloohms tens megaohms as increases. Moreover, analysis I vs. alows us determine built-in potential φ b0 0.40 eV, showing pinning Fermi level on density interface states associated dangling bonds. reverse logarithm follows quite linear law, that conduction is limited surface mechanism hopping carriers site site, each corresponding bond, in agreement theoretical results (in porous layer, are not dopants but localized bonds). Each modelled square well electrons, escape this well, have typically overcome barrier 0.10-0.30 giving an extension wave function reciprocal a˙ngstroms. Finally, possibility variable range also considered ruled out