Solvent Vapor Annealing Guides Molecules to Form a Desired Stacking Mode According to the Characteristics of the Molecular Structure

Tuning molecular structures and postprocessing technologies have always been utilized to improve the intermolecular stacking in organic semiconductor fields; solvent vapor annealing technology is likely to become the most promising option because it can select the appropriate solvent according to the characteristics of the molecular structure to optimize the intermolecular orderly arrangement. Herein, a new small molecule TEG-ID­(TPCN)­2 with a hydrophilic TEG chain was designed and applied as an active layer of memory devices to systematically study the effect of solvent selection, molecular structure, and annealing parameters on the controllable stacking of directionally induced molecules. The results showed that the memory devices based on films fabricated through the hydrophilic vapor treatment, EtOH-annealed at 6 h, exhibit satisfying performances with lower threshold voltages and higher device reproducibility because of the development of closer stacking distances and better molecule crystallinity in the solid state, which testified the fact that using appropriate solvent vapors could induce the desired intermolecular stacking mode according to the characteristics of the molecular structure.