Zhou Yijia, Zhao Xiaofeng, Chen Jiangshan, Gao Meng, He Zhaohua, Wang Shuhong, Wang Cheng
School of Chemical Engineering and Materials, Heilongjiang University, Harbin 150080, P. R. China.
School of Electronic Engineering, Heilongjiang University, Harbin 150080, P. R. China.
Langmuir. 2022 Mar 15;38(10):3113-3121. doi: 10.1021/acs.langmuir.1c03089. Epub 2022 Mar 3.
For nonvolatile memory devices, the design and synthesis of their substrate materials are very important. Due to the versatility and large-area fabrication of the low-temperature spin coating process, organic/inorganic nanomaterials as active layers of memory devices have been deeply studied. Inorganic nanoparticles can engage in interactions with polymers via external voltage. WS NPs have a large specific surface area and good conductivity. They can be used as the charge trap center in the active layer, which is conducive to the charge transfer in the active layer. Poly[2,7-9-(9-heptadecanyl)-9-carbazole--benzo[4,5] imidazole[2,1-α] isoindol-11-one] (PIIO) was synthesized via the Suzuki coupling reaction. ITO/PIIO/Al and ITO/PIIO:WS NP/Al devices were prepared by the spin coating method and vacuum evaporation technology. All devices showed tristable switching behavior. The influence of the WS mass fraction on memory performance was studied. The device composite with 6 wt % WS NPs showed the best storage features. The OFF/ON1/ON2 current ratio was 1: 1.11 × 10: 2.03 × 10, and the threshold voltage / was -0.60 V/-1.05 V. The device is steady for 12,000 s in three states-high-resistance state (HRS), intermediate state (IRS), and low-resistance state (LRS). After reading 3500 times, the switch-state current displayed no obvious attenuation. This work shows that the polymer and its composites have broad prospects in next-generation nonvolatile storage.
对于非易失性存储器件而言，其衬底材料的设计与合成至关重要。由于低温旋涂工艺具有通用性且能大面积制备，作为存储器件有源层的有机/无机纳米材料已得到深入研究。无机纳米粒子可通过外部电压与聚合物发生相互作用。WS纳米粒子具有较大的比表面积和良好的导电性。它们可作为有源层中的电荷陷阱中心，有利于有源层中的电荷转移。聚2,7-9-(9-十七烷基)-9-咔唑-苯并[4,5]咪唑[2,1-α]异吲哚-11-酮通过铃木偶联反应合成。采用旋涂法和真空蒸发技术制备了ITO/PIIO/Al和ITO/PIIO:WS NP/Al器件。所有器件均表现出三稳态开关行为。研究了WS质量分数对存储性能的影响。含有6 wt% WS纳米粒子的器件复合材料表现出最佳的存储特性。关态/开态1/开态2电流比为1:1.11×10:2.03×10，阈值电压分别为-0.60 V/-1.05 V。该器件在高阻态(HRS)、中间态(IRS)和低阻态(LRS)三种状态下可稳定12000 s。在读取3500次后，开关状态电流没有明显衰减。这项工作表明，该聚合物及其复合材料在下一代非易失性存储领域具有广阔前景。
