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41.
42.
N. A. Papanicolaou G. W. Anderson A. A. Iliadis A. Christou 《Journal of Electronic Materials》1993,22(2):201-206
In0.5Ga0.5As on silicon photodetectors, including three types of interdigitated-finger devices as well as linear photoconductors, were fabricated and measured. The InGaAs/Si structure was grown by molecular beam epitaxy and utilized a 100 Å GaAs intervening nucleation layer between the silicon substrate and the InGaAs layers, step-graded InxGa1?xAs layers, and an in-situ grown 40 Å thick GaAs surface layer, which substantially enhanced the metal-semiconductor barrier height (Φb = 0.67 V) for the InGaAs. Schottky diodes fabricated independently of the photodetectors had nearly ideal characteristics with an ideality factor (n) of 1.02 and a reverse breakdown voltage of 40 V. The interdigitated Schottky photodetectors showed dark currents between <3nA and 54 μA at a 3 V bias and initial photoresponse rise times in the range of 600 to 725 ps, comparable to similar InGaAs metal-semiconductor-metal photodetectors grown lattice matched on InP. The photoconductors fabricated in the same material had rise times in the range of 575 to 1300 ps, thus being slightly slower, and had dark currents of 7 to 80 mA. The responsivity of the photoconductors was typically greater than that of the diodes by a factor of five to fifteen. The results show potential for monolithic integration of InGaAs photodetectors on silicon substrates. 相似文献
43.
Tong B. Tang 《Journal of Electronic Materials》1975,4(6):1229-1247
Optoelectronic applications of semiconductors have been growing rapidly. They comprise photodetectors, solar cells, light
emitting diodes and lasers. This article aims to provide a general picture of the material aspect of these devices. Emphasis
is placed on material selection and underlying reasons, as well as the state-of-the-art performance. 相似文献
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Jun Shang Hongfei Qi Haifeng Feng Liang Wang Junying Zhang Yigang Wang Weichang Hao Tianmin Wang 《固体物理学:研究快报》2013,7(12):1071-1075
Silver microgrid/TiO2/ITO (indium tin oxide glass) sandwich‐structure photodetectors with various pore sizes are fabricated by a microsphere lithography strategy. This ultraviolet (UV) detector possesses ohmic contact characteristics. The high UV transmittance results from an enhanced bulk plasmon effect of the silver microgrid electrode. Photoelectric properties of the sandwich structure with various pore sizes are discussed. The short transport distance of carriers and the low blocking of incoming UV light are the main reasons of the high activity for silver microgrid/TiO2/ITO sandwich‐structure photodetectors. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
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Matthias Schulz Frank Balzer Dorothea Scheunemann Oriol Arteaga Arne Lützen Stefan C. J. Meskers Manuela Schiek 《Advanced functional materials》2019,29(16)
A facile route to soft matter self‐powered bulk heterojunction photodiode detectors sensitive to the circular polarization state of light is shown based on the intrinsic excitonic circular dichroism of the photoactive layer blend. As light detecting materials, enantiopure semiconducting small molecular squaraine derivates of opposite handedness are employed. Via Mueller matrix ellipsometry, the circular dichroism is proven to be of H‐type excitonic nature and not originating from mesoscopic structural ordering. Within the green spectral range, the photodiodes convert circular polarized light into a handedness‐dependent photocurrent with a maximum dissymmetry factor of ±0.1 corresponding to 5% overall efficiency for the polarization discrimination under short circuit conditions. On the basis of transfer matrix optical simulations, it is rationalized that the optical dissymmetry fully translates into a photocurrent dissymmetry for ease of device design. Thereby, the photodiode's ability to efficiently distinguish between left and right circularly polarized light without the use of external optical elements and voltage bias is demonstrated. This allows a straightforward and sustainable future design of flexible, lightweight, and compact integrated platforms for chiroptical imaging and sensing. 相似文献
49.
Two-dimensional(2D) anisotropic materials, such as B-P, B-As, GeSe, GeAs, ReSe2, KP15 and their hybrid systems, exhibit unique crystal structures and extraordinary anisotropy. This review presents a comprehensive comparison of various 2D anisotropic crystals as well as relevant FETs and photodetectors, especially on their particular anisotropy in optical and electrical properties. First, the structure of typical 2D anisotropic crystal as well as the analysis of structural anisotropy is provided. Then, recent researches on anisotropic Raman spectra are reviewed. Particularly, a brief measurement principle of Raman spectra under three typical polarized measurement configurations is introduced. Finally, recent progress on the electrical and photoelectrical properties of FETs and polarization-sensitive photodetectors based on 2D anisotropic materials is summarized for the comparison between different 2D anisotropic materials. Beyond the high response speed, sensitivity and on/off ratio, these 2D anisotropic crystals exhibit highly conduction ratio and dichroic ratio which can be applied in terms of polarization sensors, polarization spectroscopy imaging, optical radar and remote sensing. 相似文献
50.
Zhen Liu Shilei Dai Yan Wang Ben Yang Dandan Hao Dapeng Liu Yiwei Zhao Lu Fang Qingqing Ou Shu Jin Jianwen Zhao Jia Huang 《Advanced functional materials》2020,30(3)
Lead‐free perovskite materials are exhibiting bright application prospects in photodetectors (PDs) owing to their low toxicity compared with traditional lead perovskites. Unfortunately, their photoelectric performance is constrained by the relatively low charge conductivity and poor stability. In this work, photoresponsive transistors based on stable lead‐free bismuth perovskites CsBi3I10 and single‐walled carbon nanotubes (SWCNTs) are first reported. The SWCNTs significantly strengthen the dissociation and transportation of the photogenerated charge carriers, which lead to dramatically improved photoresponsivity, while a decent Ilight/Idark ratio over 102 can be maintained with gate modulation. The devices exhibit high photoresponsivity (6.0 × 104 A W?1), photodetectivity (2.46 × 1014 jones), and external quantum efficiency (1.66 × 105%), which are among the best reported results in lead‐free perovskite PDs. Furthermore, the excellent stability over many other lead‐free perovskite PDs is demonstrated over 500 h of testing. More interestingly, the device also shows the application potential as a light‐stimulated synapse and its synaptic behaviors are demonstrated. In summary, the lead‐free bismuth perovskite‐based hybrid phototransistors with multifunctional performance of photodetection and light‐stimulated synapse are first demonstrated in this work. 相似文献