Ultra-thin bifacial CdTe solar cell

Abstract Developing a high-quality transparent back contact, while maintaining efficient light transmission through the top absorber layer, are key components for achieving high-efficiency II–VI polycrystalline thin-film tandem solar cells. Combining these two elements, we fabricated ultra-thin bifacial CdTe solar cells (0.68 μm) with ZnTe:N/ITO transparent back contact and achieved efficiencies of 5.7% and 5.0% with illumination from the glass and the contact side, respectively. Device analysis, using ( J – V ) and QE measurements, show that the loss in efficiency is due to higher R S and J 0 as well as lower, side-dependent, photons absorption.