高性能有机晶体管存储器的制备及其空气稳定性研究

发布时间：2018-04-21 03:40

本文选题：关键字 + 有机晶体管存储器　；参考：《苏州大学》2013年硕士论文

【摘要】：随着有机电子学研究的进步，基于有机材料的晶体管存储器已经成为有机电子领域的研究热点之一。有机晶体管存储器是利用有机材料代替传统的无机半导体，绝缘体材料制成，因此有机存储器较传统的无机存储器具有以下的优势；一方面有机晶体管存储器可以制备在柔性的衬底上，适用于未来可卷曲电子设备的集成中。另一方面有机晶体管存储器可以采用简单的，低成本的溶液旋涂，打印等方法制备。近二十年来，有机晶体管存储器的研究取得了明显进展，为了适应未来应用的需求，提高有机晶体管存储器器件性能有重要意义。衡量有机晶体管存储器工作性能优异的参数主要是存储保持性，有机半导体迁移率，存储窗口和空气中操作稳定性。因此本论文将研究影响有机晶体管存储器保持性，，有机半导体迁移率，存储窗口和空气稳定性的因素，并提出优化方案。实验中采用探针台和4200-SCS型半导体特性分析系统进行器件性能的测试与分析。利用原子力显微镜（AFM）和透射电子显微镜（TEM）研究薄膜形貌。对于存储器保持性，有机半导体迁移率，存储窗口的研究，我们发现并报道了隧穿绝缘层薄膜形貌对这三方面起着决定性的影响。隧穿绝缘层薄膜形貌较差时，对金属颗粒的覆盖率就会较低，因此电荷在金属颗粒和有机半导体之间的传输便非常容易，导致存储保持性较差，窗口虚大却不稳定，有机半导体的生长也呈现无序。通过热退火改善隧穿绝缘层薄膜的形貌，使其对金属颗粒覆盖率显著提高，电荷在金属颗粒和有机半导体之间的传输就变成正常的隧穿过程，器件的保持性能得到明显的提高，有机半导体薄膜也因生长界面的改善而呈现出有序良性的薄膜形貌且体现较高的迁移率，并拥有可观稳定的存储窗口。该工作中，我们系统研究了不同退火条件下产生的隧穿绝缘层薄膜的形貌，并测试了相应的存储器性能，发现隧穿绝缘层薄膜对金属颗粒覆盖率的高低直接决定了存储器性能，并提出了热退火是提高隧穿绝缘层薄膜对金属颗粒覆盖率，制备高性能有机晶体管存储器的有效途径。关于有机晶体管存储器在空气中操作稳定性的研究，我们报道了器件在空气中操作后失效的现象并研究了失效的物理机理。研究发现空气中的氧气是导致器件存储性能衰退的成分。氧分子因其较强的电负性，很容易得到有机小分子π体系中的电子，产生P型掺杂效应，引入了大量的电子陷阱能级，使得电子不能注入到有机半导体和隧穿绝缘层界面，导致存储性能失效。这项工作说明了有机半导体材料的空气稳定性直接决定了存储器件的空气操作稳定性,并阐明了衰退的物理机制。本论文的研究通过实验分析指出了隧穿绝缘层薄膜形貌是决定有机晶体管存储器性能的重要因素，为制备高性能有机晶体管存储器件指出明确的途径，并展示了通过优化方案制备的有机晶体管存储器的优异性能。此外本文还提出了有机半导体空气稳定性对有机晶体管存储器空气稳定性的重要性，指出合成新型空气稳定的有机半导体或者引入器件封装处理是提高器件空气稳定性的有效途径，而且指出能够实现有机晶体管存储器空气操作稳定的有机半导体材料，不仅仅是要具备传统意义的多子传输空气稳定同时也要具备少子的传输空气稳定，为合成新型空气稳定有机半导体材料提出了指导方向。这些都对有机晶体管存储器走向未来有机电子学的应用有重要意义。
[Abstract]:With the progress in the research of organic electronics, the transistor memory based on organic materials has become one of the hotspots in the field of organic electronics. Organic transistor memory is made of organic materials instead of traditional inorganic semiconductors and insulators, so organic memory has the following advantages over traditional inorganic memory. On the one hand, organic transistor memory can be prepared on flexible substrates and suitable for the integration of curly electronic devices in the future. On the other hand, the organic transistor memory can be prepared by simple, low cost solution spin coating, printing and other methods.
In the last twenty years, the research of organic transistor memory has made great progress. In order to meet the needs of future applications, it is of great significance to improve the performance of organic transistor memory devices. The main parameters to measure the excellent performance of organic transistor memory are storage retention, mobility of organic semiconductors, storage windows and air operation. Therefore, this paper will study the factors that affect the retention of organic transistor memory, the mobility of organic semiconductors, the storage window and the stability of the air, and propose an optimization scheme. In the experiment, the device performance test and analysis are carried out by the probe table and the 4200-SCS type semiconductor characteristic analysis system. The atomic force microscope (AFM) and the atomic force microscope (AFM) are used in the experiment. The morphology of the film was studied by transmission electron microscopy (TEM).
For the retention of memory, the mobility of organic semiconductors, and the storage window, we found and reported that the morphology of the tunneling insulating film has a decisive influence on these three aspects. When the morphology of the tunneling insulating film is poor, the coverage of the metal particles will be lower, because the charge is transmitted between the metal particles and the organic semiconductors. It is very easy to degenerate, resulting in poor storage retention, large but unstable windows and unordered growth of organic semiconductors. Through thermal annealing, the morphology of the tunneling film is improved, the coverage of metal particles is increased significantly, and the transfer of charge between metal particles and organic semiconductors becomes a normal tunneling process, and the device is a normal tunneling process. In this work, we systematically studied the morphology of the tunnelling insulating film produced under different annealing conditions and tested the phase. It is found that the thermal annealing is an effective way to improve the coverage of the metal particles in the insulating layer of the tunnel and to prepare the high performance organic transistor memory.
In the study of the operational stability of organic transistor memory in the air, we report the phenomenon of failure after operation in the air and study the physical mechanism of the failure. It is found that oxygen in the air is a component of the deterioration of the device's storage performance. Oxygen molecules are easily obtained by their strong electronegativity. The electron in the system produces P type doping effect, which introduces a large number of electron trap energy levels, which can not be injected into the interface between the organic semiconductor and the tunneling insulating layer, causing the failure of the storage performance. This work shows that the air stability of the organic semiconductor materials directly determines the stability of the air operation of the storage devices and clarifies the decline of the air operation. The physical mechanism of retreating.
The research of this paper shows that the film morphology of the tunneling insulating layer is an important factor in determining the performance of the organic transistor memory. It is a clear way for the preparation of high performance organic transistor memory, and shows the excellent performance of the organic transistor storage device prepared by the optimization scheme. The importance of the air stability of organic semiconductors to the air stability of organic transistor memory. It is pointed out that the synthesis of new air stabilized organic semiconductors or the introduction of device packaging is an effective way to improve the air stability of the devices, and points out the organic semiconductor materials that can achieve the stable air operation of the organic transistor storage and storage devices. It is of great significance to the application of organic transistor memory to the future organic electronics.

【学位授予单位】：苏州大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：TP333

【参考文献】