Optimized Charge Transport in Molecular Semiconductors by Control of Fluid Dynamics and Crystallization in Meniscus‐Guided Coating

The effects of the casting speed and solute concentration on crystallization 2,7-dioctyl[1]benzothieno[3,2-b][1]benzothiophene (C8-BTBT) during meniscus-guided coating (MGC) are investigated, three morphological subregimes with increasing identified: I) an isotropic domain-like structure; II) unidirectionally aligned crystalline bands; III) a corrugated dendritic morphology. Interestingly, does not affect these morphologies but merely associated transition velocities. Numerical simulation both fluid dynamics in bead itself only explains trends also decrease width bands morphology II speed. They demonstrate that latter provides optimal processing window for organic field-effect transistors, minimized charge trapping, maximized on/off ratio, reliability factor.