Electron push-pull effects induced performance promotion in covalent organic polymer thin films-based memristor for neuromorphic application

• DOI: 10.1016/j.cclet.2023.109279
• Publication Date: 2023-11-08T20:22:39Z
• Authors: Panke Zhou; Hong Yu; Mun Yin Chee; Tao Zeng; Tianli Jin; Hongling Yu; Shuo Wu; Wen Siang Lew; Xiong Chen
• Keywords: Neuromorphic engineering; Memristor; Non-Volatile Memory

Covalent organic polymer (COP) thin film-based memristors have generated intensive research interest, but the studies are still in their infancy. Herein, by controlling the content of hydroxyl groups in the aldehyde monomer, Py-COP thin films with different electronic push-pull effects were fabricated bearing distinct memory performances, where the films were prepared by the solid-liquid interface method on the ITO substrates and further fabricated as memory devices with ITO/Py-COPs/Ag architectures. The Py-COP-1-based memory device only exhibited binary memory behavior with an ON/OFF ratio of 1:101.87. In contrast, the device based on Py-COP-2 demonstrated ternary memory behavior with an ON/OFF ratio of 1:100.6:103.1 and a ternary yield of 55%. The ternary memory mechanism of the ITO/Py-COP-2/Ag memory device is most likely due to the combination of the trapping of charge carriers and conductive filaments. Interestingly, the Py-COPs-based devices can successfully emulate the synaptic potentiation/depression behavior, clarifying the programmability of these devices in neuromorphic systems. These results suggest that the electronic properties of COPs can be precisely tuned at the molecular level, which provides a promising route for designing multi-level memory devices. ; This work was financially supported by the National Natural Science Foundation of China (Nos. 21972021 and 22111530111). Mr. Panke Zhou sincerely acknowledge the support of China Scholarship Council (No. 202206650013).