Memory characteristics of anthracene-based polyimides in non-volatile resistive memory devices

• Published in: Materials advances Vol. 4; no. 22; pp. 576 - 5715
• Main Authors: Lee, Seung-Hyun, Park, Sechang, Choi, Ju-Young, Choi, Yun-Je, Ji, Hyung Woo, Joung, Hyeyoung, Kim, Dam-Bi, Yoon, Kang-Hoon, Ji, Gyumin, Choi, Daeho, Lee, Jaekang, Paeng, Ki-Jung, Yang, Jaesung, Cho, Soohaeng, Chung, Chan-Moon
• Format: Journal Article
• Language: English
• Published: 13.11.2023
• ISSN: 2633-5409; 2633-5409
• DOI: 10.1039/d3ma00453h

Recently, polyimides (PIs) containing the anthracene moiety have been demonstrated to show a wide range of electrical bistable switching behavior, depending on the chemical structures or electrode materials used in the memory devices. There is a need to develop advanced anthracene-containing PIs having higher memory performance. In this study, a new anthracene-containing diamine, 4-(anthracen-9-ylmethoxy)-1,3-diaminobenzene ( AMDA ), was synthesized, and polymerized with 4,4′-(hexafluoroisopropylidene)diphthalic anhydride (6FDA) to prepare 6FDA-AMDA PI . For comparison, another PI ( 6FDA-AnDA PI ) was prepared from 6FDA and 2,6-diaminoanthracene (AnDA). 6FDA-AMDA PI and 6FDA-AnDA PI have anthracene moieties in the side and main chains, respectively. 6FDA-AMDA PI showed higher solubility in common organic solvents and less tendency of gelation compared to 6FDA-AnDA PI . The prepared PIs exhibited excellent thermal stability. The Al/ 6FDA-AMDA PI /indium tin oxide (ITO) device showed write-once-read-many times (WORM) behavior with an on/off ratio up to 10 6 , a threshold voltage of 2.40 V, and a high device yield of 80%. In contrast, the Al/ 6FDA-AnDA PI /ITO device exhibited WORM behavior with an on/off ratio of up to 10 4 , a threshold voltage at 2.50 V and a 20% device yield. The mechanisms associated with the memory effect are explained using density functional theory (DFT) and time-dependent density functional theory (TD-DFT) calculations. The lower switching voltage and higher device yield of 6FDA-AMDA PI may be attributed to more effective inter-chain charge transfer of the side-chain PI, compared to the main chain PI ( 6FDA-AnDA PI ). This study demonstrates that the 6FDA-AMDA PI is suitable as an active material for solution-processable non-volatile memories. Two anthracene-containing polyimides were synthesized and compared as an active layer in non-volatile resistive memory devices. The 6FDA-AMDA PI -based devices showed WORM behavior with an on/off ratio of up to 10 6 and a high device yield of 80%.