Employing μc-SiOX:H as n-Type Layer and Back TCO Replacement for High-Efficiency a-Si:H/μc-Si:H Tandem Solar Cells

Abstract

ABSTRACTThe n-type hydrogenated microcrystalline silicon oxide (μc-SiOX:H(n)) films with different stoichiometry have been successfully prepared by varying the CO2-to-SiH4 flow ratio in the PECVD system. By using the μc-SiOX:H(n) as a replacement for μc-Si:H(n) and ITO, the conversion efficiency of μc-Si:H single-junction and a-Si:H/μc-Si:H tandem cells were improved to 6.35% and 10.15%, respectively. The major improvement of the short circuit current density (JSC) and these cell efficiencies were originated from the increased optical absorption, which was confirmed by the quantum efficiency measurement showing increased response in the long-wavelength region. Moreover, the all PECVD process except the metal contact simplified the fabrication and might benefit the industrial production.