Synthesis and characterization of reduced grahene oxide (rGO) / tips-pentacene composite material for organic thin film transistor (OTFT) sensor platform

Organic thin film transistor (OTFT) has drawn a lot of attention due to their advantages of flexible, transparent, easy to fabricate and cost effective production. The main problem occurred in OTFT was its lower ion mobility but higher Ion/Ioff ratio which could prevent their application for high performance electronic devices. Graphene material displayed an excellent carrier mobility but lower Ion/Ioff ratio. So, the objective of this research was to develop a reduced graphene oxide (rGO)/TIPS-pentacene composite material based OTFT sensor platform to overcome these limitations. Graphene oxide (GO) was synthesized using Tour’s method and chemically reduced using ascorbic acid (LAA), fomamidinesulfinic acid (FAS) and sodium sulphite (Na2SO3). The rGO were characterized using Fourier transforms infrared spectroscopy (FTIR), X-Ray Diffraction (XRD), Thermal Gravimetric Analyzer (TGA), Field emission scanning electron microscopy (FESEM), four point probe and semiconductor parameter analyzer (SPA) to confirm the reduction of rGO. From this characterization, it was found that rGO-FAS was a better reducing agent, which resulted better device performance. For fabrication of OTFT device, polymethylmethacrylate (PMMA) and TIPS-pentacene were deposited on Poly (ethylene terephthalate) (PET) substrate by spin coating method.