Molecular Engineering of Printed Semiconducting Blends to Develop Organic Integrated Circuits: Crystallization, Charge Transport, and Device Application Analyses

Abstract

Solution-based printing has contributed to the facile deposition of various types of materials, including the building blocks of printed electronics. In particular, solution-processable organic semiconductors (OSCs) are regarded as one of the most fascinating candidates for the fabrication of printed electronics. Herein, we report electrohydrodynamic (EHD) jet-printed p-and n-type OSCs, namely 6,13-bis(triisopropylsilylethynyl)pentacene (TIPS−PEN) and 6,13-bis((triisopropylsilyl)ethynyl)-5,7,12,14tetraazapentacene (TIPS−TAP), and their use as single-OSC layers and as OSC mixed p−n layers to fabricate solutionprocessed p-, n-, and ambipolar-type organic field-effect transistors (OFETs). Use of the dragging mode of EHD jet printing, a process driven under a low electrostatic field with a short nozzle-to-substrate distance, was found to provide favorable conditions for growth of TIPS−PEN and TIPS−TAP crystals. In this way, the similar molecular structures of TIPS−PEN and TIPS−TAP yielded a homogeneous solid solution and showed ambipolar transport properties in OFETs. Therefore, the combination of single-and mixed-OSC layers enabled the preparation of various charge-transported devices from unit to integrated devices (NOT, NAND, NOR, and multivalued logic). Therefore, this fabrication technology can be useful for assisting in the production of OSC layers for practical applications in the near future.

Simulation of Crystal Nuclei at the Liquid-Air Interface toward Morphology Control via Surface Tension

“…Second, the transition points of both TIPS-PEN and TIPS-TAP locate at higher γ LA (between toluene and cyclohexane) than those of C 8 -BTBT (between octane and heptane). According to previous discussion, this divergency implies that γ CA of TIPS-TEN crystals is close to that of TIPS-TAP crystals and higher than that of C 8 -BTBT crystals, which is reasonable, since the surfaces of TIPS-PEN and TIPS-TAP crystals (also the (001) plane) − are both composed of silylethynyl groups, while the surface of C 8 -BTBT crystals is composed of alkyl chains. Hence, the systematic study of crystal growth when encountering Ag nanowires reveals how γ LA and γ CA control the crystallization location in solutions.…”

Electrohydrodynamic printing for high resolution patterning of flexible electronics toward industrial applications

“…Based on the "dragging mode" of EHD printing, Kim et al yielded high quality p-, n-, mixed p-n organic crystals. 30 By using different organic crystal layers, they achieved the manufacturing of high performance OFETs and logic circuits (Figure 10A,B). Although large-area organic crystal arrays can be manufactured by low-cost EHD printing, morphological variations of printed patterns in organic crystal arrays caused by "coffee-ring effect", such as variation in crystallinity, crystal orientation, and thickness, seriously affects its application in organic circuits.…”

“…Reproduced with permission. 30 Copyright 2022, American Chemical Society; (C) The schematic illustration of EHD printing 6,13-bis(triisopropylsilylethynyl) pentacene (TIPS-PEN) on both polyurethane acrylate (PUA)-patterned and unpatterned substrates. Reproduced with permission.…”

“…These organic crystals have uniform morphology and high crystallinity, which are conducive to charge transport. Based on the “dragging mode” of EHD printing, Kim et al yielded high quality p‐, n‐, mixed p‐n organic crystals 30 . By using different organic crystal layers, they achieved the manufacturing of high performance OFETs and logic circuits (Figure 10A,B).…”

“…Copyright 2019, Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim and Copyright 2019, The Royal Society of Chemistry. Image for “OEFTs”: Reproduced with permission 28–30 . Copyright 2014, American Chemical Society.…”