Hmar Jehova Jire L
Department of Physics and Astronomical Sciences, Central University of Jammu Rahya-Suchani, Samba 181143 J&K India
RSC Adv. 2018 Jun 5;8(36):20423-20433. doi: 10.1039/c8ra04582h. eCollection 2018 May 30.
The resistive switching memory effects in metal-insulator-metal devices with aluminium (Al) as top electrode (TE) and bottom electrode (BE). A solution processed active layer consisting of zinc oxide (ZnO) nanoparticles embedded in an insulating polyvinyl alcohol (PVA) matrix and polymer poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) has been studied by using flexible polyethylene terephthalate (PET) substrates. The current-voltage (-) measurements of hybrid Al/ZnO-PVA/PEDOT:PSS/Al/flexible PET substrate device exhibited a non-volatile bistable resistive switching behaviour, which is attributed to the trapping, storage and transport of charges in the electronic states of the ZnO nanoparticles. The performance of hybrid device is significantly enhanced over control Al/PEDOT:PSS/Al and Al/ZnO-PVA/Al devices due the presence of PEDOT:PSS polymer. This PEDOT:PSS improves the performance of oxygen ions (holes) migration toward BE and protect back oxygen vacancies (electrons) migrate toward BE from ZnO-PVA composites which may reduces the leakage current, as a result, increased the 'ON state/OFF state' current ratio of 7.9 × 10 times. The fabricated hybrid device showed high ON/OFF switching current ratio larger than five orders of magnitude with low operating voltages. It is observed that, the existence of two conducting states, namely, low conductivity state (OFF state) and high conductivity state (ON state), exhibiting bistable behaviour. The state of the device was maintained even after removal of the applied bias, indicating the non-volatile memory. The observed current-time response showed good memory retention behaviour of the fabricated devices. The excellent stability and retention performances of hybrid device verify the reliability of this device and demonstrate their potential for application in non-volatile bistable memory device. The carrier transport mechanism of the bistable behaviour for the fabricated non-volatile organic bistable devices structures is described on the basis of the - experimental results by analyzing the effect of space charge and electronic structure. Interestingly, the device performance was not degraded and remains identical even after bending the device from 60-120° angles, which indicates high potential for flexible non-volatile bistable memory device applications. This demonstration provides a class of memory devices with the potential for future flexible electronics applications.
以铝（Al）作为顶电极（TE）和底电极（BE）的金属-绝缘体-金属器件中的电阻开关记忆效应。通过使用柔性聚对苯二甲酸乙二酯（PET）基板，研究了一种由嵌入绝缘聚乙烯醇（PVA）基体中的氧化锌（ZnO）纳米颗粒和聚合物聚（3,4-乙撑二氧噻吩）聚苯乙烯磺酸盐（PEDOT:PSS）组成的溶液处理活性层。混合Al/ZnO-PVA/PEDOT:PSS/Al/柔性PET基板器件的电流-电压（I-V）测量显示出非易失性双稳态电阻开关行为，这归因于ZnO纳米颗粒电子态中电荷的俘获、存储和传输。由于PEDOT:PSS聚合物的存在，混合器件的性能相对于对照Al/PEDOT:PSS/Al和Al/ZnO-PVA/Al器件有显著提高。这种PEDOT:PSS改善了氧离子（空穴）向BE迁移的性能，并保护来自ZnO-PVA复合材料的反向氧空位（电子）向BE迁移，这可能会降低漏电流，结果使“开态/关态”电流比提高了7.9×10倍。所制备的混合器件在低工作电压下显示出大于五个数量级的高开/关切换电流比。观察到存在两种导电状态，即低导电态（关态）和高导电态（开态），呈现双稳态行为。即使去除施加的偏压后，器件的状态仍能保持，表明具有非易失性记忆。观察到的电流-时间响应显示出所制备器件良好的记忆保持行为。混合器件优异的稳定性和保持性能验证了该器件的可靠性，并证明了它们在非易失性双稳态存储器件中的应用潜力。基于实验结果，通过分析空间电荷和电子结构的影响，描述了所制备的非易失性有机双稳态器件结构双稳态行为的载流子传输机制。有趣的是，即使将器件从60°弯曲到120°角度后，器件性能也没有下降且保持不变，这表明其在柔性非易失性双稳态存储器件应用方面具有很高的潜力。这一展示提供了一类具有未来柔性电子应用潜力的存储器件。
