Enhancing the Opto-Electronic Performance of Cadmium Telluride Thin-Film Solar Cells Using Nanocone-Shaped Surface Texturing

The domination of Cadmium Telluride (CdTe) in the thin-film solar cells (TFSCs) market is expected to continue in the future and overtake other types of TFSCs. This is due to the near-optimal bandgap energy, higher absorption coefficient, and low production cost of CdTe TFSCs. However, the efficiency of CdTe TFSCs needs to be significantly improved by addressing the optical losses taking place within the solar cell. Surface reflective loss accounts for a significant portion of these optical energy losses. This study uses finite-difference time-domain (FDTD) numerical method to investigate the effect of nanocone-shaped texturing of the Cadmium Sulfide (CdS) window layer of CdTe TFSCs on the opto-electronic performance of such solar cells. The study aims to optimize the nanocone morphology, solar cell performance parameters such as short circuit current density
$(\mathbf{J}_{\mathbf{sc}})$
, open-circuit voltage
$(\mathbf{V}_{\mathbf{oc}})$
, efficiency and others have been analyzed. The results suggest 13.91% increase in
$\mathbf{J}_{\mathbf{sc}}$
and 14.13% efficiency enhancement can be achieved for nanocone texture having a diameter, height, and pitch of 600 nm, 400 nm, and 75 nm, respectively. Further comparison with plasmonic metal nanoparticle-incorporated CdTe TFSCs indicates surface texturing to be a preferable choice over plasmonic metal nanoparticles for efficient light trapping/absorption in TFSCs.