High mobility organic transistor patterned by the shadow-mask with all structure on a plastic substrate

Pentacene thin film transistors fabricated without photolithographic patterning were fabricated on the plastic substrates. Both the organic/inorganic thin films and metallic electrode were patterned by shifting the position of the shadow-mask which accompanies the substrate throughout the deposition process. By using an optically transparent zirconium oxide (ZrO2) as a gate insulator and octadecyltrimethoxysilane (OTMS) as an organic molecule for self-assembled monolayer (SAM) to increase the adhesion between the plastic substrate and gate insulator and the mobility with surface treatment, high-performance transistor with field effect mobility 0.66 cm2/V s and Ion/Ioff > 105 was formed on the plastic substrate. This technique will be applicable to all structure deposited at low temperature and suitable for an easy process for flexible display.