Trapping/detrapping induced negative differential resistance in Cu/Ni:ZnO/InGa Schottky diode

A Schottky diode based Cu/Ni:ZnO/InGa structure has been fabricated. The electrical characterization have highlighted the presence of negative differential resistance (NDR) effect and negative photoconductivity (NPC) in one device and at room temperature. The NDR effect can be explained in terms of trappings and detrapping of the mobile charges at the interface Cu/ Ni:ZnO. The main cause of the NPC effect is a combination between carriers injection by the external field and photocarriers due to UV illumination. As a result, these two features (NDR and NPC) lead to the optical switching effect in our device.