Use of bilayer gate insulator to increase the electrical performance of pentacene based transistor

Abstract

In this study, bottom-gate top-contact pentacene-based organic field effect transistors (OFET) with various spin coated ultrathin organic dielectrics on anodized aluminum oxide (Al2O3) bilayer gate dielectrics were fabricated. We have investigated the influence of the bilayer gate insulator having different combinations on the OFETs performance. Polystyrene (PS), poly-4-methylstyrene (P4MS), Poly-4-vinylphenol (PVP), poly-methylmethacrylate (PMMA) and Poly(4-vinylphenol-co-methyl methacrylate) (PVP_co_PMMA) were used as an organic dielectric. The results indicate that Al2O3 gate dielectric with Poly (4-vinylphenol) shows the optimum electrical performance with carrier mobility as large as 0.65 cm(2)/Vs, on/off current ratio of 10(6), and threshold voltage as -3.8 V.