Enhanced Mobility of Rubrene Thin-Film Transistors with a Polymer Dielectric on Plastic Substrate

Abstract

We report on the fabrication of rubrene thin-film transistors (TFTs) with spin-coated poly-4-vinylphenol (PVP) dielectric on indium-tin oxide/plastic substrate. Under a specific growth condition of 80°C in situ vacuum anneal following thermal deposition, initial amorphous rubrene film was successfully transformed into crystalline phase, both on hydrophobic PVP and on SiO 2 /p + -Si substrate, whose surface is relatively hydrophilic. The transformation or growth kinetics of the crystalline rubrene domain was much faster on PVP than on the SiO 2 gate dielectric. As a result, the rubrene TFT with PVP dielectric exhibited an order of magnitude higher field mobility (∼6 × 10 -3 cm 2 /V s) than that of the other one with SiO 2 dielectric.