An Experimental Investigation of Optical Properties of ZnS Thin Films Prepared by Chemical bath Deposition Method for Solar Energy Application

Abstract

Due to the rising competition for fossil fuels as an energy source, a
photovoltaic device couple that harvests renewable energy (solar
energy) has emerged as an alternative. The crucial components of
this device are thin film semiconductors, hence it is necessary to
create zinc sulphide thin films utilizing a variety of molar
concentrations ranging from 0.5M to 2M onto a plate of stainless
steel using a chemical bath deposition approach at a deposition
temperature of 333K. After the deposition, the thickness of the
samples was determined using a meta electronic balance technique.
Structural, Morphological and optical characterizations of the films
were made using XRD, SEM, UV-Visible and photoluminescence
spectroscopy. Microstructural Parameters deduced from XRD
profile exhibits an increase in grain size with an increase in molar
concentration (4M to14M). Optical analysis shows, that the band gap
energy values of ZnS film decreased from 3.960eV to 3.840eV with
an increase in deposition time. The photoluminescence studies
showed that the prominent peak is shifted towards a longer
wavelength region indicating loss of sulfur at high concentration:
The excellent properties obtained show that this thin film material is
good for photovoltaic device fabrication.