柔性低压有机薄膜场效应管的制备、界面修饰及电荷传输机制研究

目前，有机场效应管相对高的工作电压(> 20 V)阻碍其在有机电子领域的应用。本项目拟用高介电系数的弛豫铁电聚合物P(VDF-FrFE-CFE)作为新型有机场效应管的介电层，在柔性的PET衬底上制备出低工作电压(约3 V)、高性能的有机场效应管。弛豫铁电聚合物P(VDF-TrFE-CFE)介电常数室温高达60，能够使用溶液旋涂法制造出大面积、低漏电的介电层，可以作为新型的低压有机场效应管的绝缘介质。研究不同半导体/电介质界面对电荷传输的影响，通过界面工程，得到良好的适合电荷传输的界面。研究不同的弯曲半径和弯曲次数对这些器件的电学性能影响。本研究是一种简单而新颖的方法用溶液法在柔性衬底上制造低压有机场效应管。本研究进行的器件制造、器件物理、界面工程、器件在各种条件下的稳定性和耐用性，也极少有文献报道。随着有机半导体场效应迁移率的提高，有机场效应管实际应用非常迫切的需要进行这些方面的研究。

Organic thin film transistors (OTFTs) are encountering a great challenge in high operating voltage, which is an obstacle for their practical applications in organic electronics. This project will focus on the fabrication of low-voltage and high-qulity OTFTs with the high-k polymer gate dielectric on flexible substrates by soluiton processing. The relax ferroelectric polymer P(VDF-TrFE-CFE) with the dielectric constant of about 60 at the room temperature can be processed by spin-coating method for large-area fabrication of thin film that shows low leakage current and can be as a novel gate insulator of OTFT. We will investigate the different interfaces of the semiconductor and gate dielectric and obtain the excellent interfaces of charge transporting by interface engineering.We will also investigate that bending radii and number of bending influence on electrical properties of OTFTs. A simple and novel method is used to fabricate the low-voltage OTFTs on flexible substrates through solution processing in this study. Device fabrication, device physics, interface engineering, device stability and device durability in OTFTs in this study are rarely reported before in the literatures. With the improvement of field-effect mobility of organic semiconductors, it is necessary to study on device fabrication and device physics of OTFTs for their real application in the future.