Electrospray Deposition of Poly(3-hexylthiophene) Films for Crystalline Silicon/Organic Hybrid Junction Solar Cells

The electrospray deposition (ESD) of poly(3-hexylthiophene) (P3HT) films for use in crystalline silicon/organic hybrid heterojunction solar cells on a crystalline silicon (c-Si) wafer was investigated using real-time characterization by spectroscopic ellipsometry (SE). In contrast to the nonuniform deposition of products frequently obtained by spin-coating, a uniform deposition of P3HT films was achieved on flat and textured hydrophobic c-Si wafers by adjusting the deposition conditions. Similar findings were also obtained for the deposition of conductive poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) on P3HT. The c-Si/P3HT/PEDOT:PSS heterojunction solar cells exhibited efficiencies of 4.1 and 6.3% on flat and textured c-Si wafers, respectively. These findings suggest that ESD is a promising method for the uniform deposition of P3HT and PEDOT:PSS films on flat and textured hydrophobic substrates.