Enhancing Efficiency and Stability of CdTe-Based Solar Cells: A Simulation-Based Approach for Sustainable Energy Generation

Thin-film CdTe is a prominent material used in photovoltaic (PV) cells due to its effectiveness, affordability, and stability. The primary obstacle in this technology is creating a dependable, low-resistance, non-rectifying back contact to p-CdTe thin-film. Researchers are focusing on developing ultrathin CdTe PV cells to minimize material usage and reduce costs. The main purpose of this investigation is to model and analyze a prospect structure of a thin film CdTe solar cell by SCAPS-1D software. As research progresses, there is a growing focus on developing ultrathin CdTe PV cells. Among various methods employed to address the challenges associated with back contact, the utilization of back surface field (BSF) material is a superior, more effective, and simpler approach. This paper numerically explores the possibility of high-efficiency, ultra-thin, and stable CdTe cells with different BSF layers. Different back surface field (BSF) layers including ZnTe, C <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">u2</inf> O, C <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">u2</inf> Te, and MoTe <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> were investigated to minimize minority carrier recombination at the back contact. The cell structure with a glass/SnO <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> / AZO/CdS/CdTe/MoTe <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> configuration exhibited nearly ohmic contact with CdTe and achieved the highest efficiency of 25.03% (Voc = 1.11; Jsc = 25.79; FF = 87.87%). The simulation results confirmed that MoTe2 as the BSF layer was well-suited for efficient CdS/CdTe cells. Additionally, it was found that around 100 nm of BSF layer thickness was sufficient for achieving high efficiency. The MoTe2 layer enabled achieving more than 25% efficiency, outperforming other BSF layers.