掺杂在有机场效应晶体管中的应用进展

有机场效应晶体管(OFETs)作为一种新型的电子器件,以其柔性、可大规模简单制备等优势获得了广泛的关注。 但是,OFETs面临着器件性能不足、调控手段复杂等问题。人们尝试使用掺杂对这些问题加以解决。 本文结合本课题组的相关工作,对掺杂技术在OFETs上的应用进行归纳、总结和展望。     

有机半导体薄膜空间电荷分布对晶体管性能影响的研究进展

有机场效应晶体管(OFETs)是下一代柔性电子产业的基础元件,具有可弯曲、透明、低成本、可溶液加工等优良特性,并逐渐开始应用于生物传感器、柔性显示等领域。 然而,OFETs仍存在如工作电流小、跨导小、开关比低、空气稳定性差等问题,限制了其进一步的发展。 OFETs器件的性能主要受到导电沟道中电荷和电流分布的影响,若能通过外加手段,调控沟道中的电荷和电流分布,可能获得具有更高性能或新机理的器件。 本文结合课题组内的工作,对国内外该领域的最新进展进行综述和展望。     

基于有机(高分子)半导体和光致变色分子的场效应晶体管

作为有机电子学重要的研究内容,有机场效应晶体管(OFETs)的研究近年来得到了广泛的关注.随着应用场景的多元化,研究者对具有多功能,尤其是对特定外场刺激具有响应及存储功能的场效应晶体管的研究越来越重视.其中,在光照下发生器件性能可逆变化的有机场效应晶体管在神经突触模拟、多稳态记忆器件、非易失性存储器等功能器件领域具有潜...     

并五苯及其衍生物在有机场效应晶体管中的应用

有机场效应晶体管（organic field—effect transistors,OFETs）是以有机半导体材料作为有源层,通过电场控制电流的电子器件．与传统的无机半导体器件相比,由于其可应用于生产大面积、柔性、低成本电子设备而备受关注,在有机存储器件、有机太阳能电池、柔性平板显示和电子纸等众多领域具有潜在而广泛的应用前景．并苯类材料因其紧密的分子堆积及优异的半导体性能被广泛研究．其中,并五苯及其衍生物在场效应晶体管中表现出良好的性质,其效果甚至可以与非晶硅相媲美,但并五苯较差的溶解性及环境稳定性阻碍了其进一步应用．科研工作者通过对分子结构进行修饰改造设计,合成了一系列并五苯的衍生物,其不仅在稳定性、电学性能和溶解性方面有很大提高,还可以将该p-型半导体材料拓展到双极性及n-型半导体材料领域．本文对并五苯及其衍生物在有机场效应晶体管中的应用进行了较为全面的综述,期望对该领域的研究起到一定的推动作用．     

新型共轭聚合物的设计合成及其在场效应晶体管的应用

近年来,有机场效应晶体管(OFETs)由于在柔性器件和可穿戴电子学中的潜在应用受到了学术界和工业界的普遍关注,尤其是以聚合物半导体材料构筑的晶体管性能得到了快速的发展.如何设计合成用于OFETs的高性能聚合物半导体材料,一直是我们的追求目标.然而,分子结构对迁移率的影响仍缺少系统的比较.本文综述了近年来国内外新型聚合物材料的最新进展.我们按照材料的种类以及载流子的传输类型进行了分类,对高性能聚合物材料的发展过程、材料的设计思路以及相应的FETs性能进行了系统地归纳总结.通过研究分子及分子聚集态结构与器件性能之间的关系,希望为以后设计合成新型的高性能的聚合物材料提供有益的借鉴和指导.     

碳纳米管在生物化学传感及生物传输方面的应用

碳纳米管作为一种新型一维纳米材料具有独特的结构和性质,在生物传感、生物标记及生物传榆等研究中显示了巨大的潜力.碳纳米管在化学、生物及医药方面的研究应用具有重要的理论意义及实际意义.重点综述了碳纳米管在生物化学传感和生物传榆中的研究应用进展,并展望了其发展趋势和应用前景.     

共轭聚合物的功能化及在生物/化学分析领域的应用

共轭聚合物具有电子高度离域的共轭结构及优异的光吸收和发射特性,在有机电子、化学/生物传感、医学诊断及生物成像等领域具有广泛的应用。特定基团功能化的共轭聚合物含有可特异性识别生物/化学分子的功能基团(如糖基、生物素、羧基、氨基酸、肽段、核酸、抗体、氨基、巯基等),进一步拓宽了共轭聚合物在生物/化学分析领域的应用。本文从功能化基团的不同类别出发,对近年来共轭聚合物的功能化方法及其在生物/化学分析领域的应用(如蛋白质、病原体、Hg2+、Pb2+检测)进行了综述,并对该领域的发展前景进行了展望。     

高迁移率聚合物半导体材料最新进展

自20世纪80年代以来,聚合物半导体材料及其薄膜场效应晶体管器件(OFETs)已取得系列突破性进展.目前,已有数百种聚合物半导体材料被成功应用于OFETs中,空穴迁移率值最高已达36.3 cm~2·V~(-1)·s~(-1),可与有机小分子半导体材料甚至可同无定形硅相媲美.综述了近年来国内外高迁移率聚合物半导体的最新进展.分类对比总结和评述了空穴传输型(p-型)、电子传输型(n-型)和双极传输型聚合物半导体材料,并对聚合物半导体材料分子设计思路、薄膜OFETs器件制备及其性能参数进行了重点阐述.同时,总结了聚合物半导体材料的分子结构、聚集态结构与OFETs器件性能之间的内在关系,为今后设计与合成综合性能优异的聚合物半导体材料提供一定理论指导.     

基于聚集诱导发光荧光探针的细胞成像研究进展

荧光探针是化学传感技术领域在20世纪末的一项重大发现,具有合成简单、灵敏度高、选择性好、响应时间短、可视化高等优点。 将具有聚集诱导发光现象(AIE)特征的荧光基团与具有生物相容性的高分子结合起来,使得荧光材料具有毒性低、光稳定性好、生物相容性好等特点。 在分子、离子检测和细胞成像技术中得到广泛的研究和应用。 本文综述了细胞质成像、细胞膜成像、线粒体成像、溶酶体成像、脂滴成像、细胞核成像、细胞核和线粒体双靶向性成像的荧光探针,并对其应用前景做了展望。     

基于有机双层的双极性有机场效应晶体管研究进展

由双极性有机场效应晶体管(OFETs)制备的有机互补电路具有操作电压低、能耗低和成本低等优点,在有机互补电路方面有很大的应用前景,引起了科学家们极大的研究兴趣.同时具有高且匹配的空穴迁移率和电子迁移率的双极性有机半导体分子是制备高性能有机互补电路的必要条件之一,然而迄今为止该类双极性有机半导体分子的报道比较少,大部分双...     

Photoresponsive organic field-effect transistors involving photochromic molecules

In recent years, organic field-effect transistors (OFETs) with high performance and novel multifunctionalities have attracted considerable attention. Meanwhile, featured with reversible photoisomerization and the corresponding variation in color, chemical/physical properties, photochromic molecules have been applied in sensors, photo-switches and memories. Incorporation of photochromic molecules to blend in the device functional layers or to modify the interfaces of OFETs is common way to build photo-transistors. In this review, we focus on the recent advantages on the study of photoresponsive transistors involving one of three typical photochromic compounds spiropyran, diarylethene and azobenzene. Three main strategies are demonstrated in detail. Firstly, photochromic molecules are doped in active layers or combined with semiconductor structure thus forming photoreversible active layers. Secondly, the modification of dielectric layer/active layer interface is mainly carried out by bilayer dielectric. Thirdly, the photo-isomerization of self-assembled monolayer (SAM) on the electrode/active layer interface can reversibly modulate the work functions and charge injection barrier, result in bifunctional OFETs. All in all, the combination of photochromic molecules and OFETs is an efficient way for the fabrication of organic photoelectric devices. Photoresponsive transistors consisted of photochromic molecules are potential candidate for real applications in the future.     

2,2']Bi[naphtho[2,3-b]furanyl]: a versatile organic semiconductor with a furan-furan junction

[2,2']Bi[naphtho[2,3-b]furanyl] was synthesized, characterized, and examined as an organic semiconductor for thin-film OFETs, bilayer OPVs, and organic light-emitting transistors (OLETs). In the devices, the material acted as a p-type semiconductor, showing moderately high mobility in OFETs, good photo conversion efficiency in OPVs, and blue-green emission in OLETs.     

Recent structural evolution of lactam- and imide-functionalized polymers applied in organic field-effect transistors and organic solar cells

Organic semiconductor materials, especially donor–acceptor (D–A) polymers, have been increasingly applied in organic optoelectronic devices, such as organic field-effect transistors (OFETs) and organic solar cells (OSCs). Plenty of high-performance OFETs and OSCs have been achieved based on varieties of structurally modified D–A polymers. As the basic building block of D–A polymers, acceptor moieties have drawn much attention. Among the numerous types, lactam- and imide-functionalized electron-deficient building blocks have been widely investigated. In this review, the structural evolution of lactam- or imide-containing acceptors (for instance, diketopyrrolopyrrole, isoindigo, naphthalene diimide, and perylene diimide) is covered and their representative polymers applied in OFETs and OSCs are also discussed, with a focus on the effect of varied structurally modified acceptor moieties on the physicochemical and photoelectrical properties of polymers. Additionally, this review discusses the current issues that need to be settled down and the further development of new types of acceptors. It is hoped that this review could help design new electron-deficient building blocks, find a more valid method to modify already reported acceptor units, and achieve high-performance semiconductor materials eventually.

This review highlights the recent structural evolution of lactam- and imide-functionalized polymers applied in organic field-effect transistors and organic solar cells.     

Electron transporting semiconducting polymers in organic electronics

Significant progress has been achieved in the preparation of semiconducting polymers over the past two decades, and successful commercial devices based on them are slowly beginning to enter the market. However, most of the conjugated polymers are hole transporting, or p-type, semiconductors that have seen a dramatic rise in performance over the last decade. Much less attention has been devoted to electron transporting, or n-type, materials that have lagged behind their p-type counterparts. Organic electron transporting materials are essential for the fabrication of organic p-n junctions, organic photovoltaic cells (OPVs), n-channel organic field-effect transistors (OFETs), organic light-emitting diodes (OLEDs) and complementary logic circuits. In this critical review we focus upon recent developments in several classes of electron transporting semiconducting polymers used in OLEDs, OFETs and OPVs, and survey and analyze what is currently known concerning electron transporting semiconductor architecture, electronic structure, and device performance relationships (87 references).     

Highly Sensitive NH(3) Detection Based on Organic Field-Effect Transistors with Tris(pentafluorophenyl)borane as Receptor

We have increased organic field-effect transistor (OFET) NH(3) response using tris(pentafluorophenyl)borane (TPFB) as a receptor. OFETs with this additive could detect concentrations of 450 ppb v/v, with a limit of detection of 350 ppb, the highest sensitivity reported to date for semiconductor films; in comparison, when triphenylmethane (TPM) or triphenylborane (TFB) was used as an additive, no obvious improvement in the sensitivity was observed. These OFETs also showed considerable selectivity with respect to common organic vapors and stability toward storage. Furthermore, excellent memory of exposure was achieved by keeping the exposed devices in a sealed container stored at -30 °C, the first such capability demonstrated with OFETs.     

Strongly Correlated Alignment of Fluorinated 5,11‐Bis(triethylgermylethynyl)anthradithiophene Crystallites in Solution‐Processed Field‐Effect Transistors

The crystallinity of an organic semiconductor film determines the efficiency of charge transport in electronic devices. This report presents a micro‐to‐nanoscale investigation on the crystal growth of fluorinated 5,11‐bis(triethylgermylethynyl)anthradithiophene (diF‐TEG‐ADT) and its implication for the electrical behavior of organic field‐effect transistors (OFETs). diF‐TEG‐ADT exhibits remarkable self‐assembly through spin‐cast preparation, with highly aligned edge‐on stacking creating a fast hole‐conducting channel for OFETs.     

Hydroxy-terminated organic semiconductor-based field-effect transistors for phosphonate vapor detection

Organic field-effect transistors (OFETs) with a hydroxy-functionalized semiconductor incorporated into a receptor layer were fabricated and shown to respond strongly to the analyte dimethyl methylphosphonate (DMMP) that simulates phosphonate nerve agents. Large and reproducible source-drain current changes were observed upon exposure to DMMP vapor. Compared to single component transistors, OFETs with a mixed hydroxylated and nonhydroxylated semiconductor upper layer exhibited higher sensitivity. We further investigated the selectivity of the heterostructured OFETs by comparing responses upon exposure to different interference vapors with response to DMMP exposure. Much higher response was observed in the case of DMMP, even when the concentration of DMMP vapor was much lower than other analytes. Microstructures of OSC were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD), revealing that the organic mixture has similar crystal structure and surface morphology to those of single component OSC films, indicating that the enhanced performance of the mixture is due to its chemical properties, rather than microstructural effects.     

Microcantilevers and organic transistors: two promising classes of label-free biosensing devices which can be integrated in electronic circuits

Most of the success of electronic devices fabricated to actively interact with a biological environment relies on the proper choice of materials and efficient engineering of surfaces and interfaces. Organic materials have proved to be among the best candidates for this aim owing to many properties, such as the synthesis tunability, processing, softness and self-assembling ability, which allow them to form surfaces that are compatible with biological tissues. This review reports some research results obtained in the development of devices which exploit organic materials' properties in order to detect biologically significant molecules as well as to trigger/capture signals from the biological environment. Among the many investigated sensing devices, organic field-effect transistors (OFETs), organic electrochemical transistors (OECTs) and microcantilevers (MCLs) have been chosen. The main factors motivating this choice are their label-free detection approach, which is particularly important when addressing complex biological processes, as well as the possibility to integrate them in an electronic circuit. Particular attention is paid to the design and realization of biocompatible surfaces which can be employed in the recognition of pertinent molecules as well as to the research of new materials, both natural and inspired by nature, as a first approach to environmentally friendly electronics.     

Ladder‐Type Heteroarene‐Based Organic Semiconductors

The fusion of heteroaromatic rings into ladder‐type heteroarenes can stabilize frontier molecular orbitals and lead to improved physicochemical properties that are beneficial for applications in various optoelectronic devices. Thus, ladder‐type heteroarenes, which feature highly planar backbones and well‐delocalized π conjugation, have recently emerged as a promising type of organic semiconductor with excellent device performance in organic photovoltaics (OPVs) and organic field‐effect transistors (OFETs). In this Focus Review, we summarize the recent advances in ladder‐type heteroarene‐based organic semiconductors, such as hole‐ and electron‐transporting molecular semiconductors, and fully ladder‐type conjugated polymers towards their applications in OPVs and OFETs. The recent use of ladder‐type small‐molecule acceptor materials has strikingly boosted the power conversion efficiency of fullerene‐free solar cells, and selected examples of the latest developments in ladder‐type fused‐ring electron acceptor materials are also elaborated.