High-Speed Production of Crystalline Semiconducting Polymer Line Arrays by Meniscus Oscillation Self-Assembly

Abstract

Evaporative self-assembly of semiconducting polymers is a low-cost route to fabricating micrometer and nanoscale features for use in organic and flexible electronic devices. However, in most cases, rate is limited by the kinetics of solvent evaporation, and it is challenging to achieve uniformity over length-and time-scales that are compelling for manufacturing scale-up. In this study, we report highthroughput, continuous printing of poly(3-hexylthiophene) (P3HT) by a modified doctor blading technique with oscillatory meniscus motionmeniscus-oscillated selfassembly (MOSA), which forms P3HT features ∼100 times faster than previously reported techniques. The meniscus is pinned to a roller, and the oscillatory meniscus motion of the roller generates repetitive cycles of contact-line formation and subsequent slip. The printed P3HT lines demonstrate reproducible and tailorable structures: nanometer scale thickness, micrometer scale width, submillimeter pattern intervals, and millimeter-to-centimeter scale coverage with highly defined boundaries. The line width as well as interval of P3HT patterns can be independently controlled by varying the polymer concentration levels and the rotation rate of the roller. Furthermore, grazing incidence wide-angle Xray scattering (GIWAXS) reveals that this dynamic meniscus control technique dramatically enhances the crystallinity of P3HT. The MOSA process can potentially be applied to other geometries, and to a wide range of solution-based precursors, and therefore will develop for practical applications in printed electronics.

Large‐Scale Rapid Positioning of Hierarchical Assemblies of Conjugated Polymers via Meniscus‐Assisted Self‐Assembly

“…can be rapidly deposited into a set of intriguing large‐scale assemblies of different shapes in a one‐step manner [9–11] . Notably, such controlled evaporation of confined droplets invokes the tailoring of a three‐phase contact line (TCL) at the edge of the droplet (i.e., meniscus) via regulating the dimensions of the confined geometry, solution concentration, solvent characteristic, interfacial interaction between solute and substrate, etc [12, 13] …”

“…[9][10][11] Notably, such controlled evaporation of confined droplets invokes the tailoring of a three-phase contact line (TCL) at the edge of the droplet (i.e., meniscus) via regulating the dimensions of the confined geometry, solution concentration, solvent characteristic, interfacial interaction between solute and substrate, etc. [12,13] Among various conjugated polymers, blue-emitting PFOs have been widely recognized as an impressive model system that possesses rich yet peculiar crystal morphologies and polymorphisms, such as amorphous, semicrystalline a and a', and b phases, which can be preferentially accessed by different preparative routes. [14,15] Particularly, the b-phase of PFOs carries a series of appealing properties, including improved charge-carrier mobility, high color purity and excellent spectral stability.…”

Fabrication and applications of stimuli‐responsive micro/nanopillar arrays

“…Conversely, the bottom-up method has been devised to construct patterned nanostructures by self-assembly of molecules or particles with magnetic, 23,24 electrostatic, 25,26 or intermolecular forces. 27,28 In this case, a liquid medium is commonly employed to allow the particles to move freely for assembly. However, limitations are involved, such as lack of a periodic arrangement, defective appearance, and long process time to evaporate the solvents.…”

“…Imprinting lithography has also been introduced to construct micro and nanoscale structures of thermoplastic or ultraviolet (UV)‐curable, thermosetting resin. Conversely, the bottom‐up method has been devised to construct patterned nanostructures by self‐assembly of molecules or particles with magnetic, 23,24 electrostatic, 25,26 or intermolecular forces 27,28 . In this case, a liquid medium is commonly employed to allow the particles to move freely for assembly.…”

Recent Developments on Semiconducting Polymer Nanoparticles as Smart Photo-Therapeutic Agents for Cancer Treatments—A Review

“…A variety of nanomaterials such as organic and inorganic NIR sensitive agents have been explored for photo-therapy. Among them, semiconducting polymer nanoparticles (SPN) became very attractive recently due to their opto-electronic characteristics [ 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 ].…”