Investigation of Optoelectronic Properties of Organic Semiconductor Tetracyaoquinodimethane Based Heterostructures

Recently, interfacial layer such as metal oxide, insulator and polymer have been used by scientists between the metal and semiconductor to increase the stability of the metal-semiconductor heterojunctions. These materials have been varied according to their usage aims. In this study, graphene nanoribbons (GNR) and 7,7,8,8 Tetracyanoquinodimethane (TCNQ, C12H4N4) layer has been used as interfacial layer between the metal and semiconductor for photodiode applications. The TCNQ layer collects and extracts more electrons in the interface of the device and is used as electron acceptor material for organic solar cells. Herein, we fabricated Al/p-Si/Al, Al/p-Si/TCNQ/Al and Al/p-Si/TCNQ:GNR/Al heterojunctions by physical vapor deposition technique. I-V measurements has been employed under dark and various light illumination conditions to show dielectric properties of the fabricated heterojunctions. From current-voltage characteristics, we calculated the electronic parameters such as ideality factor, barrier heights, series resistances and rise times. It can be concluded from overall results that TCNQ and TCNQ:GNR layers had a major impact on quality and can be considered as quite proper materials for optoelectronic applications.