ZnO基纳米结构阻变式随机存储器

发布时间：2018-05-01 16:02

本文选题：阻变式随机存储器 + 高阻态　；参考：《东北师范大学》2013年硕士论文

【摘要】：阻变式随机存储器因其具有密度高、速度快和结构简单等特点而备受人们关注。然而，这类存储器经常会出现参数不稳定等弊端，如：高阻态和低阻态的阻值不稳。出现这种现象可能与其机制有关：电阻值转变的原因是电场下导电细丝会进行形成和断裂，导电细丝的形成过程是随机的，每次转变过程的导电细丝形成未见得是同一路径，这就导致了与导电细丝形成有关的参数不稳定，因此，为了提高器件的参数，我们希望能够找出一种方法来控制导电细丝的形成。与此同时，随着人们对生活品质追求的提高和电子技术的发展，电子器件的柔性化也成为当今研究的热点。但寻找到合适的材料却变成了构造柔性阻变式随机存储器的过程中的关键问题。本文的内容主要包括以下几个方面： (1)提出了50nm聚苯乙烯微球调制的纳米器件结构，试图提高器件参数的稳定性。对比Pt/IGZO/Al/SiO_2/Si的平面电极器件，聚苯乙烯微球调制结构的器件Pt/IGZO/Al/PS-NS/SiO_2/Si不但降低了器件高阻态和低阻态的离散型，还很好的提高了器件reset过程的稳定性，“good”比例从26%提高到73%。我们认为这与器件的导电细丝形成和断裂的机制有关，我们制备的这种独特的纳米结构会令器件的顶电极和底电极之间形成一种类球形电场，从而控制导电细丝的形成，以至于达到稳定参数的目的。 (2)应用旋涂技术在塑料衬底上制备了以ZnO纳米线嵌入聚甲基丙烯酸甲酯（PMMA）有机物的纳米复合材料为转换层的柔性阻变式随机存储器件。此器件展现出良好的单极性电阻转换效应（RS），具有较好的电学性能。在柔性测试中，其展示了优异的抗弯折性能以及持久的机械寿命，器件在经受不同弯折角度和多达105的弯折次数后，性能没有明显的退化，存储信息保持良好。此器件中的阻变行为可能与附着在ZnO纳米线表面的氧空位和（或者）锌离子有关，致使导电细丝（CFs）沿着ZnO纳米线方向形成。这种独特的转换机制和良好的抗弯折性能，，表明了该器件具有在柔性存储器中应用的前景。
[Abstract]:Resistive random access memory (RRAM) has attracted much attention because of its high density, high speed and simple structure. However, this kind of memory often has the disadvantages of parameter instability, such as high resistance state and low resistance state resistance instability. This phenomenon may have something to do with its mechanism: the reason for the resistance transition is that the conductive filament will form and break under the electric field, the forming process of the conductive filament is random, and the formation of the conductive filament in each transition process is not seen to be the same path. Therefore, in order to improve the device parameters, we hope to find a way to control the formation of conductive filament. At the same time, with the improvement of quality of life and the development of electronic technology, the flexibility of electronic devices has become a hot topic. However, finding suitable materials has become a key problem in the process of constructing flexible resistive random access memory (RRAM). This article mainly includes the following aspects: 1) the structure of 50nm polystyrene microspheres modulated nanoscale devices is proposed to improve the stability of device parameters. Compared with the planar electrode devices of Pt/IGZO/Al/SiO_2/Si, the polystyrene microsphere modulated device Pt/IGZO/Al/PS-NS/SiO_2/Si not only reduces the discrete state of high resistance state and low resistance state, but also improves the stability of the device reset process. The proportion of "good" increases from 26% to 73%. We think this is related to the mechanism of the formation and fracture of the conductive filament of the device, and the unique nanostructure we have prepared will form a kind of spherical electric field between the top electrode and the bottom electrode of the device, thus controlling the formation of the conductive filament. So as to achieve the purpose of stable parameters. A flexible resistive random memory device with ZnO nanowires embedded in polymethyl methacrylate (PMMA) organic nanocomposites as conversion layer was fabricated on plastic substrate by spin-coating technique. This device exhibits good unipolar resistance conversion effect and good electrical performance. In the flexibility test, it shows excellent bending performance and long mechanical life. After different bending angles and up to 105 bending times, the performance of the device does not degrade obviously, and the storage information is maintained well. The resistance behavior in this device may be related to the oxygen vacancy and / or zinc ions attached to the surface of ZnO nanowires, resulting in the formation of conducting filaments along the ZnO nanowires. The unique conversion mechanism and good flexural properties show that the device has the prospect of application in flexible memory.
【学位授予单位】：东北师范大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：TP333;TB383.1

【共引文献】