The enhancement in cell performance of CdTe-based solar cell with Si/SiO2 distributed Bragg reflectors

Abstract

In this study, the very effective design that is Distributed Bragg Reflectors (DBRs) technique and Back Surface Field (BSF) layer are used to fabricate the high-efficiency CdTe-based solar cells. The CdTe-based thin-film solar cells are fabricated as SiO2/Si(DBR)/ZnTe (BSF)/CdTe/CdS/ZnO/FTO. Then, the effects of different number of DBRs layers on CdTe-based solar cell are investigated. 68.77% reflection intensity can be obtained even in 1 period and reflection intensity can reach 99.28% in 3 periods. Significant improvement in cell output parameters are observed with increasing DBRs up to 3 periods. The highest JSC, FF and η values are obtained as 109.82 A/m2, 82.03% and 10.39%, respectively. With the rise in the DBR period, the long wavelength tail of the reflection spectrum is drawn into the center of the reflection band and the long wavelength reflectivity is reduced. This narrowing reduces the rate of reflection of low-energy photons that cannot be absorbed by CdTe layer.