Mass-Synthesized Solution-Processable Polyimide Gate Dielectrics for Electrically Stable Operating OFETs and Integrated Circuits

Abstract

Polyimides (PIs) are widely utilized polymeric materials for high-temperature plastics, adhesives, dielectrics, nonlinear optical materials, flexible hard-coating films, and substrates for flexible electronics. PIs can be facilely mass-produced through factory methods, so the industrial application value is limitless. Herein, we synthesized a typical poly(amic acid) (PAA) precursor-based solution through an industrialized reactor for mass production and applied the prepared solution to form thin films of PI using thermal imidization. The deposited PI thin films were successfully applied as gate dielectrics for organic field-effect transistors (OFETs). The PI layers showed suitable characteristics for dielectrics, such as a smooth surface, low leakage current density, uniform dielectric constant (k) values regardless of frequency, and compatibility with organic semiconductors. Utilizing this PI layer, we were able to fabricate electrically stable operated OFETs, which exhibited a threshold voltage shift lower than 1 V under bias-stress conditions and a field-effect mobility of 4.29 cm2 V−1 s−1. Moreover, integrated logic gates were manufactured using these well-operated OFETs and displayed suitable operation behavior.

A water-borne photo-sensitive polyimide precursor for an eco-friendly process of preparing organic thin film transistors

“…38,39 We also note that the e value of BPDA-pPDA from our water-borne polymer precursor is in the range of the polyimide dielectric materials (2.6-3.6) that are prepared by the conventional process using organic solvents. [40][41][42][43][44][45] The dielectric performance of the resulting PI films was further characterized. The leakage current density was measured to be 4.41 Â 10 À9 A cm À2 at 1 MV cm À1 , and the breakdown voltage was 4.4 MV cm À1 (Fig.…”

“…38,39 We also note that the ε value of BPDA- p PDA from our water-borne polymer precursor is in the range of the polyimide dielectric materials (2.6–3.6) that are prepared by the conventional process using organic solvents. 40–45…”