The calculation of electronic parameters of an Au/β-carotene/n-Si Schottky barrier diode

An Au/β-carotene/n-Si Schottky barrier diode has been fabricated by adding a solution of the non-polymeric organic compound β-carotene in chloroform on top of an n-Si substrate, and then evaporating the solvent. The β-carotene/n-Si contact shows rectifying behaviour and the reverse curves exhibit a weak bias voltage dependence. The barrier height and ideality factor values of 0.80 eV and 1.32, respectively for this structure, have been obtained from the forward bias current–voltage (I–V) characteristics. The energy distribution of the interface state density located in the inorganic semiconductor band gap at the organic compound/inorganic semiconductor interface in the energy range (Ec–0.76) to (Ec-0.53) eV have been determined from the I–V characteristics. The interface state density Nss ranges from 5.84×1012 cm−2 eV−1 in (Ec-0.76) eV to 8.83×1013 cm−2 eV−1 in (Ec-0.53) eV. The interface state density has an exponential rise with bias from the mid-gap towards the bottom of the conduction band.