Figure 5 Light J-V (a) and EQE (b) curves of the champion MoOx /c-Si(n) SCH solar cell and the reference SHJ solar cell with the same area of 274.15 cm2.
Stability investigation
Stability tests were performed for the SCH solar cells with two kinds of rear architectures of c-Si(p)/a-Si:H(i)/MoOx/ICO/Ag and c-Si(p)/a-Si:H(i)/MoOx/Ag. Both solar cells are not encapsulated and stored in an air environment with a humidity of approximately 40% RH. The results are illustrated in Fig. 6. The thin MoOx film layer (~10 nm) is very sensitive to environment such as temperature and atmosphere[34,35]. Thereby, efficiency of the SCH solar cell with the rear structure of c-Si(p)/a-Si:H(i)/MoOx/Ag rapidly decays from above 20.12% to 16.89% in 20 days (decays 16%). However, by inserting an ICO layer between MoOx and Ag, the ICO layer helps to protect the MoOx film and then the device stability improves significantly (decays 1.8%).