Pressure-Engineered CdS Thin Films via CBD for Enhanced Solar Cell Performance
Albor-Aguilera ML,
Ruíz-Ortega RC,
González-Trujillo MA,
Hernandez- Vasquez C
Cadmium sulfide (CdS) thin films are used as window material in photovoltaic solar cells technology,
where their optical transmittance, crystallinity, and surface morphology significantly influence
overall device performance. In this study, we report a novel approach to modulate the structural and
optoelectronic properties of CdS thin films by varying the reactor pressure during Chemical Bath
Deposition (CBD) process. CdS films were deposited on SnO2:F (FTO) substrates in areas of 100 cm2.
Comprehensive characterization using X-ray diffraction (XRD), scanning electron microscopy (SEM),
UV-Vis spectroscopy and Photoluminescence measurements reveal a clear correlation between reactor
pressure with optoelectronic properties. Notably, CdS films deposited at elevated pressure exhibited
a good crystalline property, atomic force microscopy (AFM) revealed non-uniform morphology on
samples. The pressure inside the reactor container led to good CdS growth with thickness around 40
nm to 90 nm an electrical resistivity value around of 103 Ω.cm. Photovoltaic CdTe solar cells were
developed by using the CdS thin films obtained as a window layer. The electrical properties of the
devices were significantly enhanced and photovoltaics efficiency increased from 8% to 15% because of
increased pressure within the reactor. This study demonstrates that the reactor pressure is a powerful
and previously underexplored parameter in CBD process, providing a scalable and cost-effective
strategy for improving the efficiency of CdS based solar cells.
