Unveiling Optoelectronic Traits in Chalcogenide Nano-Films for Photovoltaics Applications

This report presents a comprehensive analysis of dual ion beam sputtered (DIBS)
$\mathbf{Cu}_{\mathbf{2}}(\mathbf{In}_{\mathbf{2}}\mathbf{Ga})\mathbf{Se}_{\mathbf{3}}$
(CIGSe) nano-films, with a focus on their optical, compositional, and morphological properties. An innovative Al/Ga:ZnO/ZnO/CIGSe/Mo structure is proposed and evaluated using a Solar Cell Capacitance Simulator (SCAPS) tool, integrating experimental parameters to assess its suitability for photovoltaic applications. The primary objective of this analysis is to enhance device efficiency using cost-effective materials while eliminating the use of toxic CdS and substituting it with environmentally friendly and sustainable alternatives. X-ray Diffraction analysis demonstrates a strong tetragonal orientation in the CIGSe film. Spectroscopic ellipsometry reveals a band-gap of 1.57 eV and a notable absorption coefficient of approximately 10
⁴
cm 1. Integrating these experimental findings into SCAPS under standard illumination (AM 1.5), yields promising results with a photocurrent density
$(J_{\text{sc}})$
of 34.03 mA/cm
²
, open-circuit voltage
$(V_{\text{oc}})$
of 0.612 V, fill factor (FF) of 80.25%, and an impressive solar cell efficiency of 16.73%.