Optical, electrical and photovoltaic characteristics of organic semiconductor based on oxazine/n-Si heterojunction

Abstract

In this work, the construction and photoelectrical characterization of p-type organic semiconductor oxazine (OXZ) in junction with n-type silicon semiconductor are presented. The Stokes shift between absorption and emission of oxazine was analyzed. The analysis of the spectral behavior of the absorption coefficient ( α) of OXZ, in the absorption region revealed a direct transition, and the energy gap was estimated as 1.82 eV. From the current–voltage, I– V, measurements of the Au/OXZ/n-Si/Al heterojunction in the temperature range 300–375 K, characteristic junction parameters and dominant conduction mechanisms were obtained. This heterojunction showed a photovoltaic behavior with a maximum open circuit voltage, V oc, of 0.42 V, short-circuit current density, J sc, of 3.25 mA/cm 2, fill factor, FF, of 0.35 and power conversion efficiency, η, of 3.2% under 15 mW/cm 2 white light illumination.