Investigation of temperature dependent dc current transport mechanism on Au/poly(4-vinyl phenol)/p-Si device

Abstract

In this study, temperature dependent current–voltage (I–V) measurements and investigation of the dc current transport mechanism of Au/poly(4-vinyl phenol)/p-Si device have been performed. While the series resistance value displayed nearly temperature independent behaviour, the ideality factor varied between 7.26 and 2.76 in the temperature range 100–300 K. There is a linear relationship between the barrier height and the ideality factor which is attributed to barrier height inhomogeneities in the Au/poly(4-vinyl phenol)/p-Si device. The temperature dependent ideality factor behaviour shows that thermionic field emission theory is valid rather than thermionic emission theory and the characteristic tunnelling energy is calculated as 65 meV. It is concluded that poly(4-vinyl phenol) is a preferable organic insulator layer with low interface state density because the temperature dependent interface state density calculations give values of the order of 1012 eV−1 cm−2.