Characterization of the Ito/P-si Contacts Produced by Thermal Evaporation

Abstract

Indium-tin-oxide (ITO)/p-Si heterojunctions were produced by thermal evaporation using a vacuum coating unit. Cleaning process for the p-Si (1 0 0) crystal was carried out according to the conventional procedure. Prior to ITO evaporation, ohmic contact was made on the back side of the p-Si using Al (99.999%) metal. Optical transmission measurements of the ITO film was performed using a UV–Vis spectrophotometer. The fact that the ITO film shows a sharp absorbtion in a certain photon energy range points out it has a semiconductor property. So, optical band-gap of the ITO film was determined as 3.85 eV. The structural properties of the films were examined by x-ray diffraction spectroscopy (XRD). Current-voltage (I–V) measurements of the ITO/p-Si heterojuntions were performed under illumination and in dark to reveal photovoltaic and electrical properties of them, respectively. It is discovered from the I–V measurements that the ITO/p-Si heterojuctions have shown rectifier properties and exhibited low photovoltaic characteristic. © 2019 Elsevier Ltd