Room-Temperature, Solution-Processed Polyimide Gate Dielectrics for Reliable Organic Field-Effect Transistors

Abstract

Polyimide (PI) gate dielectrics are one of the most promising candidates for achieving fully solution-processed flexible organic field-effect transistors (OFETs) due to their remarkable chemical resistance, mechanical flexibility and solution processability. However, OFETs with PI dielectrics have been demonstrated only with expensive plastic or rigid substrates because of the high thermal annealing temperature for chemical imidization of the PI films. In this study, we successfully fabricated low-temperature, solution-processed OFETs by introducing the fully imidized soluble PI dielectrics. Through electrical and chemical investigations, soluble PIs are appropriate gate dielectrics for reliable, high-performance OFETs and can be processed at room temperature, namely thermal annealing-free. As a proof-of-concept,a low-temperature, solution-processed OFET with soluble PI dielectric is fabricated on ultrathin parylene C substrates and exhibits excellent mechanical durability without device performance degradation.