Influence of polymer dielectric surface energy on thin-film transistor performance of solution-processed triethylsilylethynyl anthradithiophene (TES-ADT)

This study investigates the correlation between surface energy of polymer dielectrics and the film morphology, microstructure, and thin‐film transistor performance of solution‐processed 5,11‐bis(triethylsilylethynyl) anthradithiophene (TES‐ADT) films. The low surface energy polyimide (PI) dielectric induced large grains with strong X‐ray reflections for spin‐cast TES‐ADT films in comparison to high surface en‐ ergy poly(4‐vinyl phenol) (PVP) dielectric. Furthermore, thin‐film transistors based on spin‐cast TES‐ADT films on PI dielectric exhibited enhanced electrical performance, small hysteresis, and high stability under bias stress with carrier mobility as high as 0.43 cm2/Vs and a current on/off ratio of 107. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) In this Letter, the authors demonstrate that the low surface energy polyimide (PI) dielectric induces large grains with strong X‐ray reflections for spin‐cast 5,11‐bis(triethylsilylethynyl) anthradithiophene (TES‐ADT) films. Furthermore, thin‐film transistors based on spin‐cast TES‐ADT films on PI dielectric exhibit enhanced electrical performance, small hysteresis, and high stability under bias stress.