MODELING OF THE IMPEDANCE BEHAVIOR OF AN AMORPHOUS-SEMICONDUCTOR SCHOTTKY-BARRIER IN HIGH DEPLETION CONDITIONS - APPLICATION TO THE STUDY OF THE TITANIUM ANODIC OXIDE ELECTROLYTE JUNCTION

A mathematical model to describe the impedance behaviour of the amorph ous semiconductor Schottky barrier in the high band bending region is proposed. The model is based on the admittance theory of the amorphous silicon Schottky barrier and it is valid in the polarisation region w here the semiconductor displays a Mott-Schottky like behaviour. We hav e applied the model to the characterisation of very thin (10-44 nm) am orphous oxides formed electrochemically on titanium. The calculated pa rameters are shown to be in good agreement with those obtained from th e classical (low band bending) amorphous silicon Schottky barrier theo ry for the same oxides. A comparative discussion on the advantages and handicaps of each model is carried out.