Synergetic Evolution of Diketopyrrolopyrrole-Based Polymeric Semiconductor for High Reproducibility and Performance: Random Copolymerization of Similarly Shaped Building Blocks

Abstract

A new random copolymer consisting of similarly shaped donor-acceptor building blocks of diketopyrrolopyrrole-selenophene-vinylene-selenophene (DPP-SVS) and DPP-thiophene-vinylene-thiophene (DPP-TVT) is designed and synthesized. The resulting P-DPP-SVS(5)-TVT(5) with an equal molecular ratio of the two building blocks produced significantly enhanced solubility when compared to that of the two homopolymers, PDPP-SVS and PDPP-TVT. More importantly, despite the maximum segmental randomness of the PDPP-SVS(5)-TVT(5) copolymer, its crystalline perfectness and preferential orientation are outstanding, even similar to those of the homopolymers thanks to the similarity of the two building blocks. This unique property produces a high charge carrier mobility of 1.23 cm V s of PDPP-SVS(5)-TVT(5), as determined from polymer field-effect transistor (PFET) measurements. The high solubility of PDPP-SVS(5)-TVT(5) promotes formulation of high-viscosity solutions which could be successfully processed to fabricate large-areal PFETs onto hydrophobically treated 4 in. wafers. A total of 269 individual PFETs are fabricated. These devices exhibit extremely narrow device-to-device deviations without a single failure and demonstrate an average charge carrier mobility of 0.66 cm V s with a standard deviation of 0.064. This is the first study to report on successfully realizing large-areal reproducibility of high-mobility polymeric semiconductors.

Fine Molecular Tuning of Diketopyrrolopyrrole-Based Polymer Semiconductors for Efficient Charge Transport: Effects of Intramolecular Conjugation Structure

“…Solution-processable organic field-effect transistors (FETs) based on organic semiconductors have attracted considerable attention owing to their potential use in low-cost, flexible electronic devices for various applications, such as sensors, e-papers, and backplanes of organic light-emitting diode displays. − Among the various organic semiconductors, conjugated polymers are considered the most promising candidates for next-generation organic semiconductors owing to their outstanding solution processability, mechanical robustness, and reproducibility and thus are being actively developed. − With continuous development of conjugated polymer field-effect transistors (PFETs), the charge carrier mobility of amorphous Si (0.5–1 cm 2 V –1 s –1 ) has been surpassed. − As part of this effort, structural control of conjugated polymers by changing their molecular units has been studied in combination with molecular physics, with the aim of rationalizing the design of new materials with high charge carrier mobilities. Novel high-performance polymer semiconductors have been designed and synthesized with improved chain alignment, backbone planarity, and degrees of crystallinity. − For example, a molecular design widely used in the design of conjugated polymers uses an electron donor and an electron acceptor to effectively improve intermolecular interactions and intramolecular charge transfer.…”

Influence of Simultaneous Tuning of Molecular Weights and Alkyl Substituents of Poly(thienoisoindigo-alt-naphthalene)s on Morphology and Change Transport Properties

“…π-Conjugated polymer-based organic field-effect transistors (OFETs) have received significant attention from both the academic and industrial communities, owing to their solution processability, tunability in structural modification, and potential for large-area device fabrication of low-cost, flexible, and large-area electronic applications. − Benefiting from new molecular designs and device fabrication improvements, OFETs have made considerable progress in the past decade, resulting in excellent carrier mobility approaching or surpassing that of amorphous silicon (1 cm 2 V –1 s –1 ). − In the design of semiconducting polymers, significant effort is focused on molecular packing and organization via the polymer backbone engineering, promoting the crystalline structures that in turn can facilitate the good charge carrier transport. − Therefore, the correlation between the backbone structures and OFET performances has been well established. ,,− …”