聚合物p-n结电双稳态器件

In this project, electrochemical doping will be carried out at room temperature to form a rectifying polymer p-n junction whose direction can be reversed by switching the polarity of applied voltage. The large current through a polymer p-n junction under a forward bias can be considered to be data '1'with the small current under reverse bias as the data '0'. As a result, these recitifying polymer p-n junctions are very good candidates for electrical bistable devices and will be used to realize non-volatile memory cells. Meanwhile, these polymer light-emitting p-n junctions will be used to make the electroluminescent memory cells due to their strong electroluminescence and excellent rectifying characteristics. In addition, these polymer p-n junctions will also be used to replace the inorganic p-n junction diodes as the rectifying devices in the 1D-1R polymer memory; the rectifying devices are used to avoid the "crosstalk" problem that is commonly seen due to the limited rectifying characteristics for polymer memory cells. The motivation for this replacement is that unlike the inorganic p-n junction diode, the fabrication procedure of the polymer p-n junctions is highly compatible with that of polymer memory cells, leading to a cost-effective fabrication process. Finally, the massive planar p-n junction devices will be used to profile the p-n junction structure through electrical and optical mapping and probing techniques.

本项目通过电化学掺杂在室温下实现具有整流特性的聚合物p-n结，通过改变驱动电压的极性让p-n结的方向发生反转。利用p-n结反向高阻态和正向低阻态来实现数据0和1的存储，从而实现单层全聚合物p-n结电双稳态器件。聚合物p-n结具有良好的发光特性，结合p-n结的整流特性，可以实现聚合物发光电双稳态器件。利用聚合物p-n结取代无机二极管可以实现全聚合物二极管-电阻型存储器件，这样既可以减少器件的制作难度，又可以大幅降低漏电流从而减少聚合物存储器的"误读"。同时，通过制备大尺寸平行电极的p-n结器件可以测量p-n结的电学特性从而研究掺杂与p-n结特性之间的关系。

聚合物电双稳器件是近年来有机光电子器件领域一个重要的研究方向。因其工艺简单、可折叠、成本低、存储密度大等优点，有可能成为下一代新型存储器。本研究利用制备不同的聚合物异质结实现高性能的电双稳器件。主要研究内容为：将纳米颗粒与聚合物结合制备器件；将聚合物与聚合物结合制备单层或双层器件；将聚合物与小分子有机材料相结合制备双层器件，将聚合物与有机无机杂化钙钛矿材料相结合制备器件。以上器件均展现了良好的电双稳特性，开关比最大可达到104以上，并且性能稳定。经过机理研究表明，电双稳特性主要是归因于不同电压下的电荷俘获与释放，在此基础上，明确了Fowler-Nordheim (FN) 隧穿机制和陷阱限制电流机制trapped charge-limit-current (TCLC)在不同电双稳器件上的适用范围。此外，还成功的利用全溶液法制备了高性能的柔性透明电双稳器件。