Current–voltage–temperature characteristics of PEDOT:PSS/ZnO thin film-based Schottky barrier diodes

Abstract

In this work, we report the temperature dependence of the electrical parameters of PEDOT:PSS/ZnO Schottky barrier diodes (SBDs) grown on glass substrates. To understand the current conduction mechanism, the current–voltage–temperature characteristics of PEDOT:PSS/ZnO thin film SBDs were studied. The electrical parameters were extracted with both thermionic emission and Cheung models. The obtained Richardson constant and effective barrier height were 5 A cm−2 °K−2 and 0.74 eV, respectively. The diode ideality factor was 1.5 and the series resistance was 36 Ω. All these electrical parameters turned out to be temperature independent which was associated with the dominant transport mechanisms of thermionic emission. The Richardson constant slightly deviates from theoretical values due to the presence of interfacial defects created by the preparation and deposition of PEDOT:PSS and the ZnO film crystallinity. The conductive polymer PEDOT:PSS, as a Schottky contact to ZnO, arises as an alternative to the expensive noble metals: Pt, Pd, Ag and metal oxides: IrOx, PdOx, PtOx.