I – V characterization of vacuum deposited zinc selenide – silicon hetero junction

Abstract

Zinc selenide (ZnSe) thin films were grown on silicon (Si) wafer by thermal evaporation and the hetero-structure was subjected to annealing at various temperatures. X-ray diffractogram recorded for various samples were analysed to extract the structural information including crystallite size, strain and dislocation density. ZnSe films exhibited cubic structure with (111) orientation and the crystallite size has increased from about 21 nm to 43 nm upon annealing at 673 K. Annealing at temperature above this has degraded the films. I – V characterization has shown nonlinear relation and affected by post deposition annealing. Thermionic emission and Cheung models were applied to obtain various parameters that assess the performance of hetero-structured devices. Minimum ideality factor was observed (n = 1.75 from Cheung Model) for as deposited system and it increased after annealing. Analysis has proven that series resistance increases after annealing under air ambience