窄带隙小分子和连二噻吩酰亚胺聚合物合成及场效应晶体管性能

发布时间：2018-11-01 20:35

【摘要】：有机场效应晶体管(OFET)由于具有成本低廉、材料质量轻、柔韧性好、可溶液加工和大面积制备等独特的优势在有机电子产业中有着广阔的应用前景。有机半导体材料的能级结构和分子聚集态结构决定了器件的操作、空气稳定性和载流子迁移率的大小,从而决定了OFET的性能,因此,设计合成具有合适能级结构的有机半导体材料具有重大意义。本论文主要是围绕新型半导体材料的设计、合成及OFET器件性能开展研究工作,主要研究内容有:(1)设计合成了系列新型A-D-A型小分子化合物W1-W3,这些化合物都是用并三噻吩作为供体,强的拉电子基团由2-二氰基-亚甲基-3-氰基-4,5,5-三甲基-2,5-二氢呋喃(TCF)、丙二氰(DCV)或2-乙基罗丹宁分别作为受体基团构成,并对它们的紫外-可见吸收光谱,电化学以及OFET器件性能进行了研究。实验结果显示,这些化合物都有着良好的热稳定性,在可见光区有着强的吸收。其中TCF作受体的化合物W1有着低的LUMO(-3.74eV)和窄的HOMO-LUMO带隙(1.74eV)。化合物W3的器件性能最优,其退火后的迁移率达到了4.0×10~(-2)cm~2/Vs。(2)设计合成了以苯并二噻吩为核的醌式结构分子W4和W5,对它们的热稳定性,紫外-可见吸收、电化学以及OFET器件性能等进行了研究。实验结果显示,W4和W5都具有良好的热稳定性,低LUMO能级(-4.5eV)和窄的带隙(1.2eV),是典型的窄带隙材料。另外,研究发现醌式结构的构型不同,材料在薄膜中的堆积方式也不一样,W4在薄膜状态形成的是H-型堆积,W5在薄膜状态形成J-型堆积。W4和W5都显示了典型n-型传输特性,在底栅器件中W4的电子迁移率达到了1.32×10~(-5)cm~2/Vs,W5的迁移率达到了9.30×10~(-4)cm~2/Vs。(3)设计合成了以连二噻吩酰亚胺为核的聚合物W6-W10,并对它们的热稳定性,紫外-可见吸收,电化学以及OFET器件性能进行了研究。实验结果显示,不同聚合单体的引入,可以对聚合物的能级结构进行微调。场效应晶体管测试表明,W6显示了典型的p-型传输特性,其退火后的空穴迁移率达到了0.16 cm~2V~(-1)s~(-1)。W7和W8都显示了典型的双极型传输特性,退火后其对应的迁移率分别为0.13 cm~2V~(-1)s~(-1)和4.23×10~(-2)cm~2V~(-1)s~(-1),由于其器件为底栅器件,导致其电子迁移率较低。聚合物W9和W10的晶体管性能正在进一步研究中。
[Abstract]:Due to its advantages of low cost, light material quality, good flexibility, solution processing and large area preparation, (OFET) has a broad application prospect in the organic electronics industry. The energy level structure and molecular aggregation state structure of organic semiconductor materials determine the operation of the device, air stability and carrier mobility, which determine the performance of OFET. It is of great significance to design and synthesize organic semiconductor materials with appropriate energy level structure. This thesis mainly focuses on the design, synthesis and OFET device performance of new semiconductor materials. The main research contents are as follows: (1) A series of novel A-D-A small molecular compounds W1-W3 have been designed and synthesized. All of these compounds are derived from orthotrithiophene, and the strong electron-pulling groups are composed of 2-dicyano-methylene 3-cyanoyl, 5-trimethyl-2o-5-dihydrofuran (TCF),). (DCV) or 2-ethylrhodanine were used as receptor groups, and their UV-Vis absorption spectra, electrochemistry and OFET device properties were studied. The experimental results show that these compounds have good thermal stability and strong absorption in the visible region. The TCF receptor compound W1 has low LUMO (- 3.74eV) and narrow HOMO-LUMO band gap (1.74eV). The device properties of compound W _ 3 were optimized, and its mobility reached 4.0 脳 10 ~ (-2) cm~2/Vs. (2) after annealing. The quinone structure molecules W _ 4 and W _ 5 with benzodithiophene as nucleus were designed and synthesized, and their thermal stability was obtained. UV-vis absorption, electrochemistry and the performance of OFET devices were studied. The experimental results show that both W _ 4 and W _ 5 have good thermal stability. The low LUMO level (- 4.5eV) and narrow band gap (1.2eV) are typical narrow band gap materials. In addition, it is found that different configurations of quinone structure lead to different stacking patterns of materials in thin films, and that W4 forms H- type stacking in thin films. W5 forms J-type stacking in thin film state. Both W4 and W5 show typical n-type transmission characteristics, and the electron mobility of W4 reaches 1.32 脳 10 ~ (-5) cm~2/Vs, in bottom gate devices. The mobility of W5 has reached 9.30 脳 10 ~ (-4) cm~2/Vs. (3). The polymer W6-W10 with dithiophene imide as its core has been designed and synthesized. Electrochemical and OFET device performance were studied. The experimental results show that the energy level structure of the polymer can be fine-tuned by the introduction of different polymeric monomers. Field effect transistor (FET) test shows that W6 exhibits typical p-type transport characteristics, and the hole mobility after annealing reaches 0.16 cm~2V~ (-1) s ~ (-1). W7 and W8 both show typical bipolar transmission characteristics. The corresponding mobility after annealing is 0.13 cm~2V~ (-1) s ~ (-1) and 4.23 脳 10 ~ (-2) cm~2V~ (-1) s ~ (-1) respectively. The transistor properties of the polymers W 9 and W 10 are being further studied.
【学位授予单位】：长沙理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TN386;O631

【相似文献】