PEDOT:PSS/n-Si Hybrid Solar Cells with Al₂O₃ Interfiacial Passivation Layer

Hybrid solar cells, consisting of both organic and inorganic layers have shown to be promising in developing solar cells with suitable photovoltaic properties, advantage of low temperature processing and much lower production cost than conventional p-n junction solar cells. For example, poly (3,4-ethylene-diozythiophene): polystyrenesulfonate (PEDOT:PSS) with work function of 5.1 eV and spin-coated on Si substrate leads to development of a rectifying Schottky junction and is used to design and fabricate hybrid solar cells, in which the organic PEDOT:PSS acts as a hole transporting layer. It has been shown in that the organic layer in a PEDOT:PSS/ n-Si hybrid solar cell, fabricated at temperatures below 100 C°, can also act as electron blocking layer, resulting in a low reverse saturation current density of 3.8 x 10-9 mA/cm2 and Schottky barrier height of 0.8 eV. Furthermore, Aluminum oxide (Al2O3) is shown to be effective as the passivation layer in improving the photovoltaic properties of solar cells by passivating the dangling bonds and reducing the density of surface states