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51.
Organic thin-film transistors (OTFTs) based on bottom-gate bottom-contact configuration were fabricated by inserting two kinds of modifying layers at the interface of source/drain electrode and organic semiconductor, while nitrogen dioxide (NO2) sensing capability was also evaluated based on the obtained OTFTs. Compared to OTFT without interfacial layer, the field-effect mobility (μ) was enhanced from 0.018 cm2/Vs to 0.15 cm2/Vs by incorporating with MoOx interfacial layer. Moreover, when exposed to 30 ppm NO2, the saturation current and μ of OTFT with MoOx interfacial layer increase 22.7% and 26.7%, respectively, while in original OTFT, the values are only 3.0% and 3.7%, respectively. The mechanism of performance improvement of OTFT sensor was systematically studied by focusing on the interface of source/drain electrode and organic semiconductor. The reduced contact resistance leads to higher μ, meanwhile, pentacene morphology modulation on MoOx contributes to better diffusion of NO2 molecules. As a result, higher μ and more diffused gas molecules enhance the gas sensing property of the transistor. 相似文献
52.
An efficient red phosphorescent organic light emitting diode (PhOLED) has been realized by utilizing a composite hole transporting layer comprised of all-inorganic cesium lead halide perovskite CsPbBr3 via spin-coating and 1,3-bis(9-carbazolyl) benzene (mCP) by vacuum depositing, in which CsPbBr3 film is used as a hole transporting layer and mCP plays a dominant role in electron and exciton blocking. And this PhOLED shows a saturated red emission coordinated at CIE (0.65, 0.33) driven at 7.5 V, a maximum brightness of 20,750 cd/m2, and a maximum current efficiency of 10.64 cd/A, which is as 1.87 times as that 5.68 cd/A of the reference PhOLEDs based on traditional small organic molecular hole transporting material N,N′-bis(naphthalen-1-yl)-N,N′-bis(phenyl)-benzi (NPB). The electroluminescent (EL) spectra and the energy level alignment of different PhOLEDs are investigated. The enhanced EL performances are ascribed to improved hole injecting and transporting behaviors, and better electron and exciton confinements by introducing the composite hole transporting layer CsPbBr3/mCP. 相似文献
53.
《Progress in Photovoltaics: Research and Applications》2017,25(8):696-705
Sputtering of Zn(O,S) from ZnO/ZnS compound targets has been proven to be a promising buffer layer process for Cd‐free CIGS modules due to easy in‐line integration, low cost and high efficiency on lab scale. In this publication, we report on successful upscaling of the lab process to pilot production. A record aperture efficiency of 13.2% has been reached on a 50 × 120 cm2 sized module. Neither a non‐doped ZnO layer nor additional annealing steps are required. Moreover, this very reproducible process yields a standard deviation comparable with that of the CdS base line. In contrast to lab experiments, strong performance gain after light soaking has been observed. The light‐soak‐induced power increase depends on the preparation of the window layer. Accelerated aging tests show high stability of module power. This is confirmed by outdoor testing for 20 months. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
54.
There has been an escalation in deployment and research of wireless mesh networks by both the business community and academia in the last few years. Their attractive characteristics include low deployment cost, a low‐cost option to extend network coverage and ease of maintenance due to their self‐healing properties. Multiple routes exist between the sender and receiver nodes because of the mesh layout that ensures network connectivity even when node or link failures occur. Recent advances among others include routing metrics, optimum routing, security, scheduling, cross‐layer designs and physical layer techniques. However, there are still challenges in wireless mesh networks as discussed in this paper that need to be addressed. Cross‐layer design allows information from adjacent and non‐adjacent layers to be used at a particular layer for performance improvement. This paper presents a survey of cross‐layer protocol design approaches applied to the IEEE 802.11 standards for wireless multi‐hop mesh networks that have been proposed over the last few years for improved performance. We summarize the current research efforts in cross‐layer protocol design using the IEEE 802.11 standard in identifying unsolved issues that are a promising avenue to further research. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
55.
随着科学技术的快速发展,荧光显微镜成像在生物医学领域的应用越来越广泛.常见的荧光显微镜大致可分为普通荧光显微镜、激光扫描共聚焦显微镜、超分辨率显微镜和多光子激光扫描显微镜.本文详述了几种常见显微镜的原理、特性及其在生物医学中的应用. 相似文献
56.
In this paper, we propose a new multi-task Convolutional Neural Network (CNN) based face detector, which is named FaceHunter for simplicity. The main idea is to make the face detector achieve a high detection accuracy and obtain much reliable face boxes. Reliable face boxes output will be much helpful for further face image analysis. To reach this goal, we design a deep CNN network with a multi-task loss, i.e., one is for discriminating face and non-face, and another is for face box regression. An adaptive pooling layer is added before full connection to make the network adaptive to variable candidate proposals, and the truncated SVD is applied to compress the parameters of the fully connected layers. To further speed up the detector, the convolutional feature map is directly used to generate the candidate proposals by using Region Proposal Network (RPN). The proposed FaceHunter is evaluated on the AFW dataset, FDDB dataset and Pascal Faces respectively, and extensive experiments demonstrate its powerful performance against several state-of-the-art detectors. 相似文献
57.
We have investigated a SiO_2/SiN_x/SiO_2 composite insulation layer structured gate dielectric for an organic thin film transistor(OTFT) with the purpose of improving the performance of the SiO_2 gate insulator. The SiO_2/SiN_x/SiO_2 composite insulation layer was prepared by magnetron sputtering.Compared with the same thickness of a SiO_2 insulation layer device,the SiO_2/SiN_x/SiO_2 composite insulation layer is an effective method of fabricating OTFT with improved electric characteristics and decrease... 相似文献
58.
建立了一种对称电极组交流电渗流微泵结构,通过改变相邻电极间的AC信号相位,可以方便地实现对微通道流向的控制。根据双电层离子数的空间位阻效应修正,数值求解了双电层Poisson-Boltzmann方程和液体流动Navier-Stokes方程,得到了对称电极组交流电渗微泵的流动特性。分析了微泵流速与交流电压幅值、频率等参数的关系特性,并与双电层Debye-Hückel线性解进行比较。结果表明,空间位阻效应修正在低电压时与Debye-Hückel线性解一致,但是在高电压时会产生高频反向流。 相似文献
59.
60.