Electrohydrodynamic-Jet-Printed Phthalimide-Derived Conjugated Polymers for Organic Field-Effect Transistors and Logic Gates
Zhijun Li, Yong Jin Jeong, Jisu Hong, Hyeok‐jin Kwon, Heqing Ye, Rixuan Wang, Hyun Ho Choi, Hoyoul Kong, Hyeongjin Hwang, Se Hyun Kim, Xiaowu Tang
Abstract
A π-conjugated polymer semiconductor, PBDTTTffPI, was synthesized for use as an organic semiconductor suitable for electrohydrodynamic (EHD) jet printing technology. Bulky alkylation of the polymer gave PBDTTTffPI good solubility in several organic solvents. EHD jet printing using PBDTTTffPI ink produced direct patterns of polymer semiconductors while maintaining smooth surface morphologies and crystal structures similar to those of spin-coated PBDTTTffPI films. EHD-jet-printed PBDTTTffPI was appropriate for use as a semiconductor layer in organic field-effect transistors (OFETs) and logic gates. OFETs that used EHD-jet-printed PBDTTTffPI had better electrical characteristics than devices that used spin-coated semiconductor films. When a dielectric material (Al2O3) with a high dielectric constant was introduced, the jet-printed PBDTTTffPI operated well at low voltages. Integrated devices such as inverters, NAND gates, and NOR gates were fabricated by printing PBDTTTffPI patterns and showed good switching behaviors. Therefore, the use of printable PBDTTTffPI provides an advance toward fabrication of practical integrated arrays in next-generation devices.