College of Chemistry, Chemical Engineering and Materials Science, Collaborative Innovation Center of Suzhou Nano Science and Technology, National United Engineering Laboratory of Functionalized Environmental Adsorption Materials, Soochow University , Suzhou 215123, People's Republic of China.
ACS Appl Mater Interfaces. 2017 Aug 23;9(33):27847-27852. doi: 10.1021/acsami.7b06810. Epub 2017 Aug 9.
Herein, for the first time, quaternary resistive memory based on an organic molecule is achieved via surface engineering. A layer of poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT-PSS) was inserted between the indium tin oxide (ITO) electrode and the organic layer (squaraine, SA-Bu) to form an ITO/PEDOT-PSS/SA-Bu/Al architecture. The modified resistive random-access memory (RRAM) devices achieve quaternary memory switching with the highest yield (∼41%) to date. Surface morphology, crystallinity, and mosaicity of the deposited organic grains are greatly improved after insertion of a PEDOT-PSS interlayer, which provides better contacts at the grain boundaries as well as the electrode/active layer interface. The PEDOT-PSS interlayer also reduces the hole injection barrier from the electrode to the active layer. Thus, the threshold voltage of each switching is greatly reduced, allowing for more quaternary switching in a certain voltage window. Our results provide a simple yet powerful strategy as an alternative to molecular design to achieve organic quaternary resistive memory.
本文首次通过表面工程实现了基于有机分子的四进制阻变存储器。在铟锡氧化物（ITO）电极和有机层（方酸丁酯，SA-Bu）之间插入了一层聚（3,4-亚乙基二氧噻吩）-聚（苯乙烯磺酸盐）（PEDOT-PSS），形成了 ITO/PEDOT-PSS/SA-Bu/Al 结构。经过修改的电阻式随机存取存储器（RRAM）器件实现了四进制存储切换，其最高产量（约 41%）为迄今为止最高。插入 PEDOT-PSS 层后，沉积的有机晶粒的表面形态、结晶度和镶嵌度得到了极大的改善，这为晶粒边界以及电极/活性层界面提供了更好的接触。PEDOT-PSS 层还降低了从电极到活性层的空穴注入势垒。因此，每个开关的阈值电压大大降低，从而可以在一定的电压窗口内实现更多的四进制开关。我们的结果提供了一种简单而强大的策略，作为实现有机四进制阻变存储器的分子设计替代方案。
