This scientific paper presents a study investigating
the effects of defects at the CdS/CIGS and CdS/SDL interfaces on the
performance of CIGS solar cells. The objective of this study is to analyze the
influence of defects at the interface between the CdS buffer layer and the CIGS
absorber, as well as the surface defect layer (SDL), on CIGS solar cell
performance. The study explores three key
aspects: the impact of the conduction band offset (CBO) at the CdS/CIGS
interface, the effects of interface defects and defect density on performance,
and the combined influence of CBO and defect density at the CdS/SDL and SDL/CIGS interfaces.
For interface defects not exceeding 1013 cm-2, we obtained a
good efficiency of 22.9% when -0.1 eV < CBO < 0.1 eV. By analyzing
the quality of CdS/SDL and SDL/CIGS junctions, it appears that defects at the
SDL/CIGS interface have very little impact on the performances of the CIGS
solar cell. By optimizing the electrical parameters of the CdS/SDL interface
defects, we achieved a conversion efficiency of 23.1% when -0.05 eV < CBO
< 0.05 eV.
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