Solvent Vapor Annealing Upgraded Orderly Intermolecular Stacking and Crystallinity to Enhance Memory Device Performance.

Molecular stacking and crystallinity in the film can effectively affect charge carrier mobility of semiconductor materials and corresponding device performance. Currently, solvent vapor annealing (SVA) as an effective thin film optimization strategy, which can select the appropriate solvent according to the characteristics of the molecular structure to optimize the intermolecular orderly arrangement, is often adopted. Thus, a small conjugated molecule C 20 -ID(TPCN)2 with flexible alkyl side chains is synthesized and applied as active layer of sandwich memory devices, the active layer film has been annealed with different polar solvent vapor to evaluate the relationship among the molecular structure, solvent selection, annealing parameters and intermolecular stacking. Compared to un-annealed devices, the memory devices based on the films through CH 2 Cl 2 -annealed show better performance with lower threshold voltage due to developing ordered molecular aggregation and better crystallinity, while the hydrophilic solvent vapor will weaken the device performance. This work not only reveals selecting appropriate solvent vapor for the molecular structure could be of vital importance in inducing the desired intermolecular stacking mode, but also provides a novel insight for the realization of excellent organic semiconductor devices performance.