The calculation of electronic properties of an Ag/chitosan/n-Si Schottky barrier diode

Abstract

In this study, the film of chitosan by adding the solution of chitosan being a polymeric compound on the top of an n-Si substrate and then by evaporating solvent was formed. It was seen that the chitosan/n-Si contact demonstrated clearly rectifying behavior and the reverse curves exhibit a weak bias voltage dependence by the current–voltage ( I– V) curves studied at room temperature. Average barrier height and ideality factor values for this structure were determined as 0.94 eV and 1.81, respectively. Furthermore, the energy distribution of the interface state density located in the semiconductor band gap at the chitosan/n-Si substrate in the energy range ( E c−0.785) to ( E c−0.522) eV have been determined from the I– V characteristics. The interface state density N ss ranges from 5.39 × 10 12 cm −2 eV −1 in ( E c−0.785) eV to 1.52 × 10 13 cm −2 eV −1 in ( E c−0.522) eV. The interface state density has an exponential rise with bias from the midgap towards the bottom of the conduction band.