Stable encapsulated organic TFT with a spin-coated poly(4-vinylphenol-co- methyl methacrylate) dielectric

The influences of encapsulation on the hysteresis and the gate-bias-stress effects (both positive and negative gate bias stresses) of pentacene organic thin-film transistors (OTFTs) with poly(4-vinylphenol) and poly(4-vinylphenol- co-methyl methacrylate) (PVP-PMMA) gate dielectrics are investigated. The encapsulation and the use of less polar gate dielectrics like PVP-PMMA copolymers are both important to suppress moisture adsorption and to obtain a stable pentacene OTFT. Compared to the air-stable OTFT with a fluoropolymer dielectric, the stable encapsulated OTFT with a PVP-PMMA dielectric is a low-cost promising candidate for mass production consideration.