Improving organic memory performance through mounting conjugated branches on a triphenylamine core

To study the influence of the number of branches mounted on molecular backbones on the thin-film morphology and performance of their memory devices, we successfully synthesized three conjugated small molecules containing triphenylamine and benzothiazole moieties (TPA-nBBT, n = 1, 2, 3) and studied their memory performances. Binary static random access memory (SRAM) characteristics could be achieved for the three compound-based devices with a sandwich-like configuration of ITO/molecule/Al. The device based on TPA-3BBT exhibited the best device performance with the lowest threshold voltage and the best thermal stability which is related to the temperature insensitive thin-film morphology and film crystallinity. Our results demonstrate that increasing the number of branches in D-A conjugated molecules to adjust film morphology and intermolecular accumulation may be an effective strategy to improve the stability and performance of devices.