Investigation of solution processed molybdenum oxide as selective contacts for silicon solar cells application

Abstract

We have studied hole selective contacts molybdenum oxide (HyMoOx) fabricated based on solution process and the performance of HyMoOx/c-Si heterojunction solar cells. Characterization of the HyMoOx film revealed an amorphous structure with a low surface roughness of 1.27 nm, chemical composition of HyMoO2.72, high transmittance on glass of over 85%, bandgap of 3.0 eV and low conductivity of 10−6 S/cm. It also possesses a work function of ∼4.95 eV and good passivation effect on c-Si, as the Si surface recombination velocity is observed to reduce by a factor of 85 when passivated by HyMoOx film. The solution processed MoOx as a selective contact on silicon has a low saturation current J0 ∼ 150 fA/cm2 but with a high contact resistivity ∼5.6 Ωcm2. The fabricated HyMoOx/c-Si solar cell has the best power conversion efficiency (PCE) of 8.22%, open circuit voltage (Voc) of 463 mV, short circuit current density (Jsc) of 31.16 mA/cm2, and fill factor (FF) of 56.87%.