An Inkjet‐Printed, Ultralow Voltage, Flexible Organic Field Effect Transistor

A very simple procedure for fabricating inkjet‐printed organic field effect transistors (OFETs) is reported. A reliable process for the deposition of a thin and uniform polymeric dielectric film of poly(4‐vinylphenol) (PVP) is established as a key factor for obtaining high performance devices operating at low voltages. To this aim, ink formulations, printing parameters, and cross‐linking processes are investigated. Morphological characterization of the fabricated films by means of contact profilometry and atomic force micro­scopy is provided, as well as capacitive measurements proving ideal dielectric properties. OFET structures based on PVP gate dielectric are reported: in particular, inkjet‐printed devices operated at voltages below 1 V with remarkable transistor performances such as high charge carrier mobility and low subthreshold swing are presented.