The role of interface states and series resistance on the I– V and C– V characteristics in Al/SnO 2/p-Si Schottky diodes

Abstract

In order to good interpret the experimentally observed non-ideal Al/SnO 2/p-Si (MIS) Schottky diode parameters such as the barrier height Φ B, series resistance R s and density of interface states N ss, a calculation method has been reported by taking into account interfacial oxide layer and ideality factor n in the current transport mechanism. The current–voltage ( I– V) and capacitance–voltage ( C– V) characteristics of MIS diodes are studied over a wide temperature range of 80–350 K. The effects of R s, interfacial layer and N ss on I– V and C– V characteristics are investigated. The values of n were strongly temperature dependent and decreased with increasing temperature. The energy distribution of N ss was determined from the forward bias I– V characteristics by taking into account the bias dependence of the effective barrier height. The mean N ss estimated from I– V and C– V measurements decreased with increasing temperature. The R s estimated from Cheung’s functions was strongly temperature dependent and decreased with increasing temperature. The I– V characteristics confirmed that the distribution of N ss, R s and interfacial layer are important parameters that influence the electrical characteristics of MIS devices.