A Conjugated Polymer Bearing Perylenediimide (PDI) and Ferrocene (Fc) Exhibiting Stable Data-Storage Performance

Polymeric materials have been widely researched and used as active-layers to fabricate data-storage resistance random-access memory (ReRAM) devices. Nevertheless, the problems as drift voltage, weak stability, and low reproducibility largely restrict their practical application in next-generation memory systems, mainly induced by the molecular stacking defects that limited the efficient charge-carrier migration throughout the active-layers. Thus, how to weaken the molecular stacking defects and thus improve the overall ReRAM performance is a scientific issue that needs to be solved urgently. In this work, an organometallic polymer 5,12-di(thiophen-2-l)-2,9-di(tridecan-7-yl)anthra[2,1,9-def:6,5,10-d'e'f']diisoquinoline-1,3,8,10(2H,9H)-tetraone P(DTPDI-Fc) is designed with ferrocene (Fc) and perylenediimide (PDI) building repeats. The X-ray diffraction (XRD) test confirms the regioregular stacking styles of P(DTPDI-Fc) in solid states, and atomic force microscope (AFM) measurement verified the continuous and smooth surface morphology of P(DTPDI-Fc) films. Therefore, the charge carriers can easily inject into P(DTPDI-Fc) film and can efficiently migrate throughout P(DTPDI-Fc) films. Thus, P(DTPDI-Fc) devices show excellent memory behaviors with low high-conductance state ON-state current, stable threshold voltage, long-time stability, and high device reproducibility. This work affords a practical strategy to weaken molecular stacking defects and to improve stacking regioregularity, which will give a guidance for the designing of multilevel data-storage ReRAM devices in future researches. Through introducing Fc and PDI repeats into polymeric backbone, polymer P(DTPDI-Fc) is designed to weaken stacking defects. P(DTPDI-Fc) films show a regioregular molecular stacking and a continuous surface morphology, highly advantageous to the charge carriers inject and transport throughout P(DTPDI-Fc) films. Therefore, P(DTPDI-Fc) devices exhibit low ON-state current, stable threshold voltage, long-time stability, and high device reproducibility.image