OTFT with Silk Screen Printed Drain and Source

With the aim to develop low cost production of organic integrated circuits, the implementation of silk screen printing appears as a possible process. Here, we described the step of drain and source electrodes fabrication on flexible substrate (PPC: poly (Phthalate Carbonate). To assess this printing technology in terms of geometrical resolution and electrical performances, pentacene transistors with different channel length, have been realized in the top contact design. The drain and source electrodes, 1 μm thick, have been deposited by silk screen printing by means of silver ink. The insulated layer is spin coated with a PMMA solution. On the top, the organic semi-conductor pentacene film is obtained by thermal vapor deposition. We present the classical electric characteristics, I=f (VDS) and I=f (VGS), of the resulting transistors, as a function of the geometrical parameters. Satisfying parameters are obtained with non purified amorphous pentacene.