Passivation of Al/Si interface by chemical treatment:: Schottky barrier height and plasma etch induced defects

The influence of different chemical treatment on the electrical behaviur of n- and p-type Al/Si Schottky junctions was studied. A Schottky barrier height of 0.91 eV was achived due probably to the unpinning of the Fermi-level at the Al/Si interface. This is one of the highest barrier height values reported so far for a solid-state Schottky junction prepared to p-Si. A doping level reduction was observed in the vicinity of Si surface for wafers with native oxide and for those annealed in forming gas. It was observed unexpectedly that the reactive plasma etch used for formation of mesa structures, decreases the apparent Schottky barrier height.