Current-voltage characteristics of iron-implanted silicon based Schottky diodes

Abstract

Current-voltage (I–V) measurements were carried out on undoped and iron (Fe) doped n-silicon (n-Si) to establish and study a change in electrical properties of the material-based diodes with Fe doping concentration. Fe doping was achieved by implantation at the energy of 160 keV to fluences of 1015, 1016 and 1017 ion/cm2. The obtained results indicated that the diodes were well fabricated and Fe doping resulted in a diode behaviour changing from normal exponential to ohmic I–V behaviour. This ohmic behaviour was explained in terms of Fe-induced defect levels that were positioned at the centre of the energy gap. An I–V ohmic region increased with fluence indicating that the density of defect levels has increased with Fe implantation fluence. A change in diode conduction mechanism domination and parameters with fluence were investigated. The obtained I–V properties of Fe doped Si-based diodes were similar to those of the diodes that were fabricated on radiation-hard materials indicating that Fe, too, is a promising dopant in a quest to improve radiation-hardness of Si to be used in high energy physics experiments.