Interface investigation of planar hybrid n-Si/PEDOT:PSS solar cells with open circuit voltages up to 645 mV and efficiencies of 12.6 %

We have studied interface formation properties of hybrid n-Si/PEDOT:PSS solar cells on planar substrates by varying the silicon substrate doping concentration (N (D)). Final power conversion efficiencies (PCE) of 12.6 % and open circuit voltages (V (oc)) comparable to conventional diffused emitter pn junction solar cells have been achieved. It was observed, that an increase of N (D) leads to an increase of V (oc) with a maximal value of 645 mV, which is, to our knowledge, the highest reported value for n-Si/PEDOT:PSS interfaces. The dependence of the solar cell characteristics on N (D) is analyzed and similarities to minority charge carrier drift-diffusion limited solar cells are presented. The results point out the potential of hybrid n-Si/PEDOT:PSS interfaces to fabricate high performance opto-electronic devices with cost-effective fabrication technologies.