Investigation of current‐voltage characteristics and current conduction mechanisms in composites of polyvinyl alcohol and bismuth oxide

Abstract

Temperature dependent current‐voltage (I–V) measurements of Au/Polyvinyl Alcohol + Bi2O3/n‐Si structure were conducted between 100 and 350 K for investigating the temperature dependence of I–V characteristics and current conduction mechanisms in the structure. Series resistance of the structure is calculated using Ohm's law and Cheungs' method. Ideality factor (n) and zero‐bias barrier height (ΦBo) were obtained considering thermionic emission theory. From 100 to 350 K, n changed from 32.1 to 3.54, and ΦBo changed from 0.27 to 0.99 eV. Obtained temperature dependent values of n and ΦBo suggested that thermionic emission is not the dominant current conduction mechanism. Therefore, Ln(I)–Ln(V) curves of the studied structure were plotted for investigating current conduction mechanisms in the structure and current flow is explained considering space charge limited current. Moreover, density of interface states (Dit) in the structure were calculated and its temperature dependence was investigated such that Dit values are reduced to the order of ∼1013 eV−1 cm−2 from ∼1014 eV−1 cm−2 with increasing temperature. POLYM. ENG. SCI., 54:1811–1816, 2014. © 2013 Society of Plastics Engineers