Mechanical Properties of Organic Electronic Polymers on the Nanoscale. (25th November 2021)

• Record Type: Journal Article
• Authors: Panchal, Vishal; Dobryden, Illia; Hangen, Ude D.; Simatos, Dimitrios; Spalek, Leszek J.; Jacobs, Ian E.; Schweicher, Guillaume; Claesson, Per M.; Venkateshvaran, Deepak
• Is Part Of: Advanced Electronic Materials. Volume 8:Number 3(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2021-11-25
• Subjects: nanomechanics -- organic electronics -- organic field‐effect transistors -- organic semiconducting polymers -- young's modulus; Materials -- Electric properties -- Periodicals; Materials science -- Periodicals; Magnetic materials -- Periodicals; Electronic apparatus and appliances -- Periodicals; 537
• DOI: 10.1002/aelm.202101019
• Languages: English
• ISSNs: 2199-160X

Abstract

Abstract: Organic semiconducting polymers have attractive electronic, optical, and mechanical properties that make them materials of choice for large area flexible electronic devices. In these devices, the electronically active polymer components are micrometers in size, and sport negligible performance degradation upon bending the centimeter‐scale flexible substrate onto which they are integrated. A closer look at the mechanical properties of the polymers, on the grain‐scale and smaller, is not necessary in large area electronic applications. In emerging micromechanical and electromechanical applications where the organic polymer elements are flexed on length scales spanning their own micron‐sized active areas, it becomes important to characterize the uniformity of their mechanical properties on the nanoscale. In this work, the authors use two precision nanomechanical characterization techniques, namely, atomic force microscope based PeakForce quantitative nanomechanical mapping (PF‐QNM) and nanoindentation‐based dynamical mechanical analysis (nano‐DMA), to compare the modulus and the viscoelastic properties of organic polymers used routinely in organic electronics. They quantitatively demonstrate that the semiconducting near‐amorphous organic polymer indacenodithiophene‐co‐benzothiadiazole (C16‐IDTBT) has a higher carrier mobility, lower modulus, and greater nanoscale modulus areal uniformity compared to the semiconducting semicrystalline organic polymer poly[2, 5‐bis(3‐tetradecylthiophen‐2‐yl)thieno[3, 2‐b]thiophene] (C14‐PBTTT). Modulus homogeneity appears intrinsic to C16‐IDTBT but can be improved in C14‐PBTTT upon chemical doping. Abstract : Nanomechanical devices built from organic semiconductors require a deeper understanding of the mechanical properties on the scale of an individual polymer grain. In this report, the surface nanomechanical texture of high mobility polymers traditionally used for organic electronics is quantified together with their depth dependent viscoelastic response.