Microcontact-printed self-assembled monolayers as ultrathin gate dielectrics in organic thin-film transistors and complementary circuits

We have developed a manufacturing process for organic thin-film transistors and organic complementary circuits in which a microcontact-printed phosphonic acid self-assembled monolayer is employed first as an etch resist to pattern aluminum gate electrodes by wet etching and then as the gate dielectric of the same device. To our knowledge, this is the first report of a printing process for electronic devices that combines the concepts of direct and indirect printing in the same printing step and for the same material by employing a transferred pattern both as an etch resist (indirect printing) and as a functional material as part of the final device (direct printing). Owing to the small thickness and the high quality of the monolayer gate dielectric, the transistors and circuits operate at a low voltage of 3 V.