Roll-to-roll compatible OTFT manufacturing technique by lamination

Here we present a new roll-to-roll printing compatible technique to manufacture organic thin film transistors using two substrates that are laminated together. The lamination idea and benefits have been presented previously in literature [1-4]. Lamination has been used in a pentacene OTFT when the interface was studied with quartz or silicon substrate [1]. Another uses prepatterned substrate to make the electrode contact [2]. Single crystals [3] or sheets [4] have been laminated on silicon wafers. In this work we present the lamination of two plastic foils with prepatterned metal electrodes and polymer layers. Lamination of the sheets containing semiconductor on one and dielectric on the other side together will allow usage of materials with non-compatible solvents (no need for orthogonal solvent) [4]. Also the surface microstructure might be formed differently when laminating dry films together compared to film formation from soluble ink [4]. This difference might be the reason for better life time of the demonstration transistor. As a demonstration, we present a polymer transistor manufactured by the lamination technique in air. Transistor has shown very good air stability. After initial settling the parameters have reached stable values and they have lasted for over 300 days in ambient conditions. The trend indicates a lifetime measured in years.