Charge carrier mobility improvement in diketopyrrolopyrrole block‐copolymers by shear coating

Research output: Contribution to journalResearch articleContributedpeer-review

Contributors

  • Kristina Ditte - , Chair of Organic Chemistry of Polymers, Leibniz Institute of Polymer Research Dresden (Author)
  • Nataliya Kiriy - , Leibniz Institute of Polymer Research Dresden (Author)
  • Jonathan Perez - , Chair of Organic Devices (cfaed), Leibniz Institute for Solid State and Materials Research Dresden (Author)
  • Mike Hambsch - , Chair of Organic Devices (cfaed) (Author)
  • Stefan C.B. Mannsfeld - , Chair of Organic Devices (cfaed) (Author)
  • Yulia Krupskaya - , Leibniz Institute for Solid State and Materials Research Dresden (Author)
  • Ramesh Maragani - , Martin Luther University Halle-Wittenberg (Author)
  • Brigitte Voit - , Chair of Organic Chemistry of Polymers, Leibniz Institute of Polymer Research Dresden (Author)
  • Franziska Lissel - , Leibniz Institute of Polymer Research Dresden, TUD Dresden University of Technology, Friedrich Schiller University Jena (Author)

Abstract

Shear coating is a promising deposition method for upscaling device fabrication and enabling high throughput, and is furthermore suitable for translating to roll‐to‐roll processing. Although common polymer semiconductors (PSCs) are solution processible, they are still prone to mechanical failure upon stretching, limiting applications in e.g., electronic skin and health monitoring. Progress made towards mechanically compliant PSCs, e.g., the incorporation of soft segments into the polymer backbone, could not only allow such applications, but also benefit advanced fabrication methods, like roll‐to‐roll printing on flexible substrates, to produce the targeted devices. Tri‐block copolymers (TBCs), consisting of an inner rigid semiconducting poly‐diketo‐pyrrolopyrrole‐thienothiophene (PDPP‐TT) block flanked by two soft elastomeric poly(dimethylsiloxane) (PDMS) chains, maintain good charge transport properties, while being mechanically soft and flexible. Potentially aiming at the fabrication of TBC‐based wearable electronics by means of cost‐efficient and scalable deposition methods (e.g., blade‐coating), a tolerance of the electrical performance of the TBCs to the shear speed was investigated. Herein, we demonstrate that such TBCs can be deposited at high shear speeds (film formation up to a speed of 10 mm s−1). While such high speeds result in increased film thickness, no degradation of the electrical performance was observed, as was frequently reported for polymer−based OFETs. Instead, high shear speeds even led to a small improvement in the electrical performance: mobility increased from 0.06 cm2 V−1 s−1 at 0.5 mm s−1 to 0.16 cm2 V−1 s−1 at 7 mm s−1 for the TBC with 24 wt% PDMS, and for the TBC containing 37 wt% PDMS from 0.05 cm2 V−1 s−1 at 0.5 mm s−1 to 0.13 cm2 V−1 s−1 at 7 mm s−1. Interestingly, the improvement of mobility is not accompanied by any significant changes in morphology.

Details

Original languageEnglish
Article number1435
Number of pages14
JournalPolymers
Volume13
Issue number9
Publication statusPublished - 1 May 2021
Peer-reviewedYes

External IDs

ORCID /0000-0002-8487-0972/work/142247513
WOS 000650704200001
PubMed 33946975
ORCID /0000-0002-4531-691X/work/148607606

Keywords

Keywords

  • Block copolymers, Organic field‐effect transistors, Shear coating, Shear speed, Thickness-dependent mobility