Impact of the interfacial traps on the charge accumulation in organic transistors

A silver nanoparticles (NPs) self-assembled monolayer (SAM) was introduced in the pentacene organic field-effect transistors using modified Langmuir–Schaffer (horizontal lifting) technique, and its effect was being evaluated electrically using current–voltage (I−V) and impedance spectroscopy (IS) measurements. The I−V results showed a significant negative threshold voltage shift indicating that hole trapping phenomena exist inside the devices with about two orders higher in the contact resistance and an order lower in the effective mobility when a SAM was introduced. The IS measurements with the simulation of Maxwell–Wagner equivalent circuit revealed that the incorporation of the NPs SAM had a comparable negative voltage shift as in I–V measurements with a higher trapping time based on the simulation results.