PEDOT:PSS emitters on multicrystalline silicon thin-film absorbers for hybrid solar cells

摘要

We fabricated an efficient hybrid solar cell by spin coating poly(3,4-ethylene-dioxythiophene): polystyrenesulfonate (PEDOT:PSS) on planar multicrystalline Si (mc-Si) thin films. The only 5 μm thin Si absorber layers were prepared by diode laser crystallization of amorphous Si deposited by electron beam evaporation on glass. On these absorber layers, we studied the effect of SiO_x and Al_2O_3 terminated Si surfaces. The short circuit density and power conversion efficiency (PCE) of the mc-Si/Al_2O_3/PEDOT:PSS solar cell increase from 20.6 to 25.4mA/cm~2 and from 7.3% to 10.3%, respectively, as compared to the mc-Si/SiO_x/PEDOT:PSS cell. Al_2O_3 lowers the interface recombination and improves the adhesion of the polymer film on the hydrophobic mc-Si thin film. Open circuit voltages up to 604 mV were reached. This study demonstrates the highest PCE so far of a hybrid solar cell with a planar thin film Si absorber.