Air Stable High Resolution OFET (Organic Field Effect Transistor) Fabrication Using Inkjet Printing and Low Temperature Selective Laser Sintering Process

A novel high resolution OFET (organic field effect transistor) fabrication process has been developed to realize low cost, large area electronics at low processing temperature without use of expensive, high temperature lithography process in vacuum. A drop-on-demand (DOD) ink-jetting system was used to print gold nano-particles suspended in Alpha-Terpineol solvent. Continuous Argon ion laser was irradiated locally to evaporate carrier solvent as well as sinter gold nano-particles in order to fabricate metal source and drain electrodes with high resolution and minimal thermal damage to the substrate. PVP (poly-4-vinylphenol) in Hexanol solvent and air-stable semiconductor polymer (Carboxulate - functionalized Polythiophenes) in 1,2-dichlorobenzene (o-DCB) solvent were spin-coated to form thin film of dielectric layer and semiconducting active layer. All of the processes were carried out in plastic-compatible low temperature, ambient air and atmospheric pressure environment. The OFETs showed good accumulation mode p-channel transistor behavior with carrier mobility of 0.01cm2/V·s and Ion/Ioff ratio of ranging from 103 to 104.