Temperature dependent of electrical characteristics of Au/n-GaAs/In Schottky diode with In2S3 interfacial layer obtained by using spray pyrolysis method

Abstract

A study on Au/n-GaAs Schottky barrier diodes parameters with and without thin In2S3 thin films, fabricated on n-type GaAs grown by Spray Pyrolysis Method (SPM), has been made. The film nanostructure features have been characterized by XRD, SEM and EDAX techniques. The Au/n-GaAs/In and Au/In2S3/n-GaAs/In junctions are investigated the electrical characteristics with Current-Voltage (I–V) measurements at room temperature. The Current-Voltage-Temperature (I–V–T) and Capacity–Voltage–Temperature (C–V–T) characteristics of Au/In2S3/n-GaAs/In structure are determined in the temperature wide range 300–20 K with 20 K steps. Some electrical parameters such as ideality factor n, zero bias barrier height ΦBo and series resistance RS are extracted from I–V–T curves using Thermionic Emission (TE) method and modified Norde functions. It is observed that the barrier height decreases and the ideality factor increases with the decrease temperature. Such behavior is attributed to barrier inhomogeneities by assuming a Gaussian distribution of barrier heights at the interface for two regions. Furthermore, from the C–V–T measurement of the structure ΦB(CV), donor concentration (ND), Fermi level (EF) and diffusion potential (VD) have been calculated in the temperature range of 300–20 K at 500 kHz applied frequency.