有机半导体在溶液中取向生长机制及其薄膜的形貌表征
发布时间：2019-02-13 14:14
【摘要】：溶液法制备有机半导体薄膜具有低成本、环境友好等优势,成为目前有机薄膜晶体管(Organic thin film transistors,OTFTs)研究领域的热点。其中,浸渍提拉技术和喷墨打印技术由于大面积取向和数字直写图案化制膜的优势成为OTFT制备工艺开发的重要基点。本文基于浸渍提拉与喷墨打印技术制备有源层薄膜,研究有机半导体分子在溶液中实现取向生长的机制及其薄膜的表征,并进一步对OTFT器件性能进行研究,主要内容如下:(1)采用浸渍提拉技术制备大面积取向的6, 13-双(三异丙基甲硅烷基乙炔基)并五苯(6,13 bis(tri-isopropylsilylethynyl)pentacene,TIPS-并五苯)薄膜,其取向成膜机制是由溶液内部微观梯度作用产生特定方向的毛细流控制,这种作用机制与混合墨水兼容,且薄膜的覆盖率与溶液粘度成正比。此外,采用倾斜2θ扫描模式来表征TIPS-并五苯晶体的面内织构,较高粘度的氯仿溶液中浸渍提拉制备的TIPS-并五苯薄膜的晶格具有较大的α角和较小的γ角,及其较小的晶格常数b,该器件表现出高达1.5cm2V-1s-1的迁移率。(2)通过在衬底构建非对称的立体结构,利用非对称立体结构在空间区域上的表面曲率的变化,在喷墨打印TIPS-并五苯的前驱体溶液表面形成不对称的表面张力作用及表面能梯度,进而驱动有机半导体发生取向生长及其自对准效果。基于这种非对称立体结构制备的OTFT器件的平均迁移率提升40 %,同时迁移率的相对标准差由68%减小到39%,表明有机半导体在微尺度区域取向生长的阵列器件的性能及其均匀性都获得明显提升。(3)基于 2,7-二辛基-二苯并噻吩(2,7-dioctyl[1]benzothieno[3,2-b][1]Benzothiophene, C8-BTBT) 材料,采用喷墨打印工艺制备 OTFT 的有源层。首先,通过优化打印点间距、打印衬底温度达到高性能器件的制备(最大迁移率达到1cm2V-1s-1左右,开关比超过106),进一步分析了该条件下不同修饰衬底喷墨打印单线条薄膜的形貌,发现在较疏水及低粗糙度的聚(4-乙烯基苯酚)(poly-4-vinyl phenol,PVP)及苯乙基三氯硅烷(phenethyltrichlorosilane,PETS)修饰衬底上得到均匀性好、覆盖率高且结晶有序堆积的薄膜形貌及高性能的器件,并研究了PVP衬底的阵列器件的性能均匀性及其稳定性,其阵列器件性能表现均匀,且放置时间超过40天之后仍能保持良好的器件性能(迁移率保持在1 cm2V-1s-1左右)。
[Abstract]:The preparation of organic semiconductor thin films by solution method has the advantages of low cost and environmental friendliness, and has become a hot spot in the field of organic thin film transistors (Organic thin film transistors,OTFTs). Among them, the dipping Czochralski technique and inkjet printing technology have become the important base point for the development of OTFT preparation process due to the advantages of large area orientation and digital direct writing patterning. In this paper, the active layer films were prepared by impregnation Czochralski and inkjet printing techniques. The mechanism of organic semiconductor molecules orientation growth in solution and the characterization of the films were studied, and the properties of OTFT devices were also studied. The main contents are as follows: (1) large area oriented 6,13-bis (triisopropylmethylsilyl acetynyl) pentabenzene (6o 13 bis (tri-isopropylsilylethynyl) pentacene,TIPS- penta-benzene) thin films were prepared by impregnation Czochralski technique. The oriented film-forming mechanism is controlled by the micro-gradient effect of the solution, which is compatible with the mixed ink, and the coverage of the film is proportional to the viscosity of the solution. In addition, the in-plane texture of TIPS- pentaben crystals was characterized by tilting 2 胃 scanning mode. The lattice of TIPS- pentaben films prepared by impregnation and Czochralski in chloroform solution with higher viscosity has larger 伪 angle and smaller 纬 angle. And its smaller lattice constant b, the device exhibits a mobility up to 1.5cm2V-1s-1. (2) by constructing an asymmetric stereoscopic structure on the substrate, the surface curvature of the asymmetric stereoscopic structure changes in the spatial region. Asymmetric surface tension and surface energy gradient were formed on the precursor solution surface of TIPS- pentabenzene, which drives the orientation growth and self-alignment of organic semiconductors. The average mobility of OTFT devices based on this asymmetric stereoscopic structure is increased by 40%, and the relative standard deviation of mobility is reduced from 68% to 39%. It is shown that the properties and homogeneity of organic semiconductor arrays grown in microscale region orientation have been significantly improved. (3) based on 2O7-dioctyl [1] benzothieno [3t2-b] [1] Benzothiophene,. (3) based on 2O7-dioctyl [1] benzothieno [3t2-b] [1] Benzothiophene, C8-BTBT) material, the active layer of OTFT was prepared by inkjet printing process. First of all, by optimizing the printing point spacing, the substrate temperature can be used to fabricate high performance devices (the maximum mobility is about 1cm2V-1s-1 and the switching ratio is more than 106). The morphologies of single-line films on different modified substrates by inkjet printing were further analyzed. It was found that poly (4-vinylphenol) (poly-4-vinyl phenol,PVP) and phenylethyl trichlorosilane (phenethyltrichlorosilane,) were found to be hydrophobic and low roughness in the presence of polyvinyl phenol (poly-4-vinyl phenol,PVP) and phenylethyl trichlorosilane (phenethyltrichlorosilane,). PETS) was used to fabricate the films with good homogeneity, high coverage and ordered crystalline stacking. The homogeneity and stability of the PVP substrate array devices were studied, and the performance of the array devices was uniform. The device performance (mobility is about 1 cm2V-1s-1) can be maintained after the placement time is more than 40 days.
【学位授予单位】：合肥工业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TN304.5;TN321.5
本文编号：2421631
[Abstract]:The preparation of organic semiconductor thin films by solution method has the advantages of low cost and environmental friendliness, and has become a hot spot in the field of organic thin film transistors (Organic thin film transistors,OTFTs). Among them, the dipping Czochralski technique and inkjet printing technology have become the important base point for the development of OTFT preparation process due to the advantages of large area orientation and digital direct writing patterning. In this paper, the active layer films were prepared by impregnation Czochralski and inkjet printing techniques. The mechanism of organic semiconductor molecules orientation growth in solution and the characterization of the films were studied, and the properties of OTFT devices were also studied. The main contents are as follows: (1) large area oriented 6,13-bis (triisopropylmethylsilyl acetynyl) pentabenzene (6o 13 bis (tri-isopropylsilylethynyl) pentacene,TIPS- penta-benzene) thin films were prepared by impregnation Czochralski technique. The oriented film-forming mechanism is controlled by the micro-gradient effect of the solution, which is compatible with the mixed ink, and the coverage of the film is proportional to the viscosity of the solution. In addition, the in-plane texture of TIPS- pentaben crystals was characterized by tilting 2 胃 scanning mode. The lattice of TIPS- pentaben films prepared by impregnation and Czochralski in chloroform solution with higher viscosity has larger 伪 angle and smaller 纬 angle. And its smaller lattice constant b, the device exhibits a mobility up to 1.5cm2V-1s-1. (2) by constructing an asymmetric stereoscopic structure on the substrate, the surface curvature of the asymmetric stereoscopic structure changes in the spatial region. Asymmetric surface tension and surface energy gradient were formed on the precursor solution surface of TIPS- pentabenzene, which drives the orientation growth and self-alignment of organic semiconductors. The average mobility of OTFT devices based on this asymmetric stereoscopic structure is increased by 40%, and the relative standard deviation of mobility is reduced from 68% to 39%. It is shown that the properties and homogeneity of organic semiconductor arrays grown in microscale region orientation have been significantly improved. (3) based on 2O7-dioctyl [1] benzothieno [3t2-b] [1] Benzothiophene,. (3) based on 2O7-dioctyl [1] benzothieno [3t2-b] [1] Benzothiophene, C8-BTBT) material, the active layer of OTFT was prepared by inkjet printing process. First of all, by optimizing the printing point spacing, the substrate temperature can be used to fabricate high performance devices (the maximum mobility is about 1cm2V-1s-1 and the switching ratio is more than 106). The morphologies of single-line films on different modified substrates by inkjet printing were further analyzed. It was found that poly (4-vinylphenol) (poly-4-vinyl phenol,PVP) and phenylethyl trichlorosilane (phenethyltrichlorosilane,) were found to be hydrophobic and low roughness in the presence of polyvinyl phenol (poly-4-vinyl phenol,PVP) and phenylethyl trichlorosilane (phenethyltrichlorosilane,). PETS) was used to fabricate the films with good homogeneity, high coverage and ordered crystalline stacking. The homogeneity and stability of the PVP substrate array devices were studied, and the performance of the array devices was uniform. The device performance (mobility is about 1 cm2V-1s-1) can be maintained after the placement time is more than 40 days.
【学位授予单位】：合肥工业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TN304.5;TN321.5
【参考文献】
相关期刊论文 前1条
1 赵鹏;;拉曼光谱的原理[J];时代教育(教育教学);2011年09期
相关硕士学位论文 前1条
1 元淼;基于喷墨打印工艺的小分子有机薄膜晶体管的制备和性能研究[D];合肥工业大学;2015年
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