Investigation of CdSe and ZnSe as Potential Back Surface Field Layers for CdTe‐Based Solar Cells: A Study from First Principles Calculations

Abstract A class of II–VI semiconductors, especially CdTe, is a highly photo‐reactive compound that would be suitable for photovoltaic applications. However, being resistive material, CdTe produces considerable contact resistance and drastically reduces the efficiency devices. Introducing back surface field layer at region may significantly improve device's performance. This work investigates suitability using ZnSe CdSe as back‐surface‐field in CdTe‐based solar cells through accurate electronic structure calculations hybrid‐density functional theory method. The show both ZnSe/CdTe CdSe/CdTe behave type‐II heterojunctions with band gaps 2.0 1.1 eV, respectively. Mulliken electronegativity method used to determine correct edge positions concerning vacuum level all pristine semiconductors their interfaces. Calculation shows significant charge redistribution interface leads formation an effective local near heterostructures. help separate photogenerated electron–hole pairs active by pushing opposite charges into two different sections heterojunction. Additionally, also exhibit better light‐absorption characteristics visible light range.