Gamma induced effects on structural, optical and electrical properties of n-TiO2/p-Si heterojunction

Abstract

This study reports the fabrication of n-TiO2/p-Si heterojunction by deposition of TiO2 thin films on p-Si substrate. The effect of gamma doses on structural, optical and the current–voltage (I–V) characteristics of n-TiO2/p-si heterojunction were studied. Measurements performed with the aid of X-ray diffraction revealed that deposited thin film was composed of nanocrystalline mixture of anatase and rutile phases, which change to TiO2 anatase phase after irradiation. Optical properties were evaluated based on diffuse reflectance and photoluminescence measurements. The I–V characteristics were measured to investigate the heterojunction effects at different gamma doses. Some parameters including ideality factor (n), barrier height (ΦB) and series resistance (Rs) were calculated from I–V characteristics before and after irradiation. Experimental results indicated that structural, optical and electrical parameters of n-TiO2/p-si heterojunction were influenced by the gamma radiation doses.