Effect of PEDOT:PSS Layer Deposition on Electrical and Photoelectrical Properties of n + -ZnO/ n -Si Heterostructure

The results of electrical and photoelectrical characterization of the interface and bulk properties of n + -ZnO/ n -Si and poly(3,4-ethylene dioxythiophene):poly(styrenesulfonate) (PEDOT:PSS)/ n + -ZnO/ n -Si heterostructures are presented. It was found that the PEDOT:PSS layer deposited on the surface of zinc oxide increases the potential barrier at the ZnO/Si interface, leading to higher band bending in the silicon, which is important for solar cell applications. The recombination rate at the interface decreases because of the creation of an inversion layer in the silicon under operational conditions. The increase of the potential barrier in PEDOT:PSS/ n + -ZnO/ n -Si heterostructures results in the increase of the open-circuit voltage by 54–180%. The external quantum efficiency in PEDOT:PSS/ n + -ZnO/ n -Si heterostructures increases by 100% at 450 nm.