Optimizing the Synthesis and Structural Refinement of CdTe Thin Films for High-Performance Solar Cells

Abstract

The growing need and requirement of renewable energy sources have given rise to enormous developments in solar technologies where CdTe (Cadmium Telluride) thin-film solar cells are proving to be the potential alternative to the conventional silicon based solar devices. Optimization of the synthesis and structural optimization of CdTe thin films are carried out in this research towards the realization of better optical, electrical and mechanical properties of the material to be used in photovoltaic applications as high as possible. Different synthesis methods such as Chemical Bath Deposition (CBD), Close-Spaced Sublimation (CSS) and Atomic Layer Deposition (ALD) were investigated to grow films with thickness, uniformity and crystallinity. The study of post-deposition treatments including annealing and surface passivation was also carried out in order to further enhance the performance of the material. To assess the crystalline structure, surface morphology and optical properties of the films, characterization techniques, namely X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), UV-Vis Spectroscopy, Raman Spectroscopy, and Fourier Transform Infrared (FTIR) spectroscopy were used. Optimized CdTe thin films as investigated and presented in the results section are strongly crystalline with well distributed particles and effective charge transport properties critical in enhancing the efficiency of solar cells. This piece of work shows the relevance of optimization of synthesis and structural improvement towards the development of CdTe based solar cells as a low cost, high efficiency green energy harvesting technology.