Download or read book Design Fabrication and Characterization of Terahertz Quantum well Photodetectors written by Shengxi Huang (S.M.) and published by . This book was released on 2013 with total page 144 pages. Available in PDF, EPUB and Kindle. Book excerpt: Terahertz (THz) photodetectors are important in the fully exploration and development of electromagnetic spectrum. However, a fast and sensitive THz photodetector ready for array integration is not available. A THz Quantum-well Photodetector (QWP) has the properties of being fast, sensitive, low-noise, and narrow-band. It is promising for large-array integration for THz imaging. In addition, a THz QWP-LED (Light-Emitting Diode) can upconvert the THz to NIR radiation and useful for THz imaging in Focal-Plane Array (FPA). In this thesis project, the theory of the intersubband transition and carrier transport in a THz QWP is studied. The designe, fabrication, measurement-system buildup, and characterization are performed. In addition, the design and fabrication process of THz QWP-LED are also carried out. Such devices have potential applications in many fields such as biology, medication and security.

Download or read book Pfrontener Obstb ume written by and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Theory Fabrication and Characterization of Quantum Well Infrared Photodetectors written by Janet L.. Pan and published by . This book was released on 2000 with total page 83 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Theory Fabrication and Characterization of Quantum Well Infrared Photodetectors written by Janet L. Pan and published by . This book was released on 2000 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Design Fabrication and Characterization of Quantum Cascade Terahertz Emitters written by Vinod M. Menon and published by . This book was released on 2001 with total page 230 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Design Fabrication and Characterization of In GA Al As Ga Al As Quantum Dot Infrared Photodetectors for High temperature Operation written by Adrienne Diarra Stiff-Roberts and published by . This book was released on 2004 with total page 496 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Design and Characterization of Strained layer Quantum Well Infrared Photodetectors written by Jerome T. Chu and published by . This book was released on 1998 with total page 258 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Terahertz Biomedical and Healthcare Technologies written by Amit Banerjee and published by Elsevier. This book was released on 2020-08-11 with total page 264 pages. Available in PDF, EPUB and Kindle. Book excerpt: Terahertz Biomedical and Healthcare Technologies: Materials to Devices reviews emerging advances in terahertz biomedical and healthcare technologies, including advances in fundamental materials science research, device design and fabrication, applications, and challenges and opportunities for improved performance. In addition, the improvement of materials, optical elements, and measuring techniques are also explored. Other sections cover the design and development of wide bandgap semiconductors for terahertz device applications, including their physics, device modeling, characterization and fabrication concepts. Finally, the book touches on potential defense, medical imaging, internet of things, and the machine learning applications of terahertz technologies. Reviews the latest advances in the fundamental and applied research of terahertz technologies, covering key topics in materials science, biomedical engineering and healthcare informatics Includes applications of terahertz technologies in medical imaging, diagnosis and treatment Provides readers with an understanding of the machine learning, pattern recognition, and data analytics research utilized to enhance the effectiveness of terahertz technologies

Download or read book Fabrication and Characterization of Antimony Type II Quantum Well Photodetectors written by Bradley J. Rawlins and published by . This book was released on 2003 with total page 90 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Design Fabrication and Measurement of Ion implanted Quantum Well Infrared Photodetectors written by Naser Hatefi Kargan and published by . This book was released on 2007 with total page 312 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Development of High Performance Multicolor Quantum Well Infrared Photodetectors and Studies of Enhancing Light Coupling and Radiation Effects in QWIPs written by and published by . This book was released on 1999 with total page 128 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this report, we present the design, fabrication, and characterization of several high performance multi-color and broadband quantum well infrared photodetectors (QWIPs) for both MWIR and LWIR applications. The report covers tasks performed during the period from March 3, 1998 through July 10, 1999. A very high sensitivity, high-strain, multi-color triple-coupled (TC- ) QWIP using InGaAs/AlGaAs/InGaAs material systems has been developed in this project for LWIR multi-color detection. A two-stack InGaAs/AlGaAs/InGaAs TC-QWIP and InGaAs/AlGaAs TC-QWIP has been developed for the LWIR and MWIR dual-band detection. In addition, a high-strain InGaAs/GaAs TC-QWIP with and without two-dimensional (2-D) grating coupler has been designed, fabricated, and characterized for the LWIR detection. This device shows very high responsivity under 450 back-illumination. Several broadband (BB- ) QWIPs have been developed for the LWIR detection. These include (1) two-stack, five-well n-type InGaAs/AlGaAs broadband (BB- ) QWIPs with 3- and 7-period QWs in the unit cell, (2) 3- and 4-well n-type BB-QWIPs, and (3) two 3- and 4- well p-type BB-QWIPs. In addition, a three-stack InGaAs/AlGaAs/InGaAs BB TC-QWIP grown on GaAs substrate has been developed for LWIR detection, which has a FWHM spectral bandwidth twice larger than the single-stack TC-QWIP. Finally, a MWIR InGaAs/InAlAs TC-QWIP grown on InP substrate, operating up to T = 116K with excellent device performance, has also been demonstrated. Four journal papers and six conference papers have been published and presented from this work.

Download or read book GUIA do produtor written by and published by . This book was released on 1996 with total page 252 pages. Available in PDF, EPUB and Kindle. Book excerpt: Administração direta; Secretaria de política grícola-SPA; Abastecimento agropecuário; Secretaria de desenvolvimento rural-SDR; Assistência técnica e extensão rural; Conservação de solo e água; Cooperativismo e associativismo rural; Informação agrícola; Infra-estrutura rural; Mecanização e aviação agrícolas; Produção animal; Produção vegetal; Secretaria de defesa agropecuária-SDA; Defesa animal; Inspeção de produtos de origem animal; Defesa e inspeção vegetal; Endereços (EMATER, DEA, Convênios de classificação vegetal, Criadores de bovinos e laboratórios); Comissão especial de recursos-CER; Comissão executiva do plano da lavoura cacaueira-CEPLAC; Instituto naional de meteorologia-INMET; Administração indireta; Instituto nacional de colonização e reforma agrária-INCRA; Companhia Nacional de Abastecimento-CONAB; Empresa brasileira de pesquisa agropecuária -EMBRAPA; Companhia de colonização do nordeste-COLONE.

Download or read book Multi Color Quantum Well Infrared Photodetectors for Mid Long and Very Long Wavelength Infrared Applications written by Sheng S. Li and published by . This book was released on 2002 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt: Quantum well infrared photodetectors (QWIPs) have been widely investigated for the 3 - 5 micrometers mid-wavelength infrared (MWIR) and 8 - 12 micrometers long-wavelength infrared (LWIR) atmospheric spectral windows as well as very long wavelength infrared (VLWIR: lambda(sub c)> 14 micrometers) detection in the past decade. The mature III-V compound semiconductor growth technology and the design flexibility of device structures have led to the rapid development of various QWIP structures for infrared focal plane arrays (FPAs) applications. In addition to the single-color QWIP with narrow bandwidth, the multi-color QWIP required for advanced IR sensing and imaging applications have also been emerged in recent years. Using band gap engineering approach, the multi-color (2, 3, and 4- color) QWIPs using multi-stack quantum wells with different well width and depth and voltage-tunable triple-coupled quantum well (TCQW) structure for detection in the MWIR, LWIR, and VLWIR bands have been demonstrated. In this paper, the design, fabrication, and characterization of a voltage-tunable 2-stack 3-color QWIP for MW/LW/LW IR detection and a 3-stack 3-color QWIP for detection in the water, ozone, and CO2 atmospheric blocking bands are depicted.

Download or read book Advances in Infrared Photodetectors written by and published by Elsevier. This book was released on 2011-05-03 with total page 385 pages. Available in PDF, EPUB and Kindle. Book excerpt: Semiconductors and Semimetals has distinguished itself through the careful selection of well-known authors, editors, and contributors. Originally widely known as the "Willardson and Beer" Series, it has succeeded in publishing numerous landmark volumes and chapters. The series publishes timely, highly relevant volumes intended for long-term impact and reflecting the truly interdisciplinary nature of the field. The volumes in Semiconductors and Semimetals have been and will continue to be of great interest to physicists, chemists, materials scientists, and device engineers in academia, scientific laboratories and modern industry. Written and edited by internationally renowned experts Relevant to a wide readership: physicists, chemists, materials scientists, and device engineers in academia, scientific laboratories and modern industry

Download or read book Characterization of Quantum Well Infrared Photodetectors written by Yingkai John Liaw and published by . This book was released on 2002 with total page 82 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Ultra fast Antenna coupled Mid infrared Quantum well Photodetectors written by Quyang Lin and published by . This book was released on 2021 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This Thesis is devoted to the conception, fabrication and experimental characterization of semiconductor-based ultra-fast photodetectors operating in the mid-infrared range (~3-12um). More specifically, the detectors that I have developed, generally known as multi-quantum-well infrared photodetectors (QWIPs), rely on intersubband (ISB) transitions in a GaAs-Al_0.2Ga_0.8As heterostructure, where an electron occupying the ground state of a quantum-well is photoexcited into an upper state, lying next to the energy continuum above the AlGaAs barriers.In my work I have exploited a specific device geometry that allows light-coupling at normal incidence, based on a two-dimensional array of electrically connected metallic patch-antennas. Each antenna is obtained by sandwiching the GaAs-AlGaAs multi-quantum-well heterostructure between a top contact metal layer and a bottom metallic ground plane, effectively forming a square metal-dielectric-metal microcavity, where the fundamental TM electromagnetic mode is resonant with the energy of the ISB transition. Finally, to allow for broadband microwave extraction, the antenna array is connected to a 50Ohm, monolithically integrated coplanar waveguide.In the first part of my work I have designed the antennas for optimum detection at 10um wavelength. This was done by running a set of simulations using a commercial electromagnetic solver based on the finite-difference time-domain (FDTD) method. Based on the results of the simulations I have fabricated a set of preliminary structures, without coplanar waveguide, to characterize the optical properties of the antenna array through Fourier transform micro-reflectance measurements. These measurements have allowed me to select the optimum patch array dimensions, namely the lateral size of the square-patch and the array periodicity.The second part of my work has been dedicated to the fabrication of the complete QWIP detector, including the monolithically integrated coplanar waveguide. In these detectors the size of the two-dimensional antenna array has been kept to a minimum, without compromising the radiation collection, in order to reduce as much as possible the device parasitic RC time constant and therefore maximize the detector speed. I have fabricated two generations of detectors relying on two slightly different active regions, respectively based on a bound-to-bound and a bound-to-continuum design. In the final part of my PhD I have also fabricated a third generation of devices, where the patch array, rather than to a coplanar waveguide, is connected to a spiral THz antenna. This device has not been characterized in this work and I present its relevance in the context of this Thesis in the perspectives.The last part of the Thesis is dedicated to the electro-optical characterization of the fabricated detectors. First, I have measured the dark current, the polarization dependence, and the dc photoresponse, that allowed me to determine the responsivity at 77K and 300K. Then I characterized the microwave frequency response of the detectors. To this end I have participated to the setup of an experimental apparatus based a high-speed (67GHz) cryogenic probe station. In this apparatus the beams of two quantum cascade lasers (QCLs) emitting at 10.3um wavelength, are simultaneously focused on the QWIP detector to generate a hererodyne signal at their difference frequency. By temperature/current tuning the emission wavelength of one QCL the heterodyne frequency can be swept continuously, thus allowing the measurement of the detector frequency response with the help of a spectrum analyzer. At room-temperature I obtain a flat frequency response up to 70GHz, solely limited by the bandwidth of the acquisition electronics. This is the broadest RF- bandwidth reported to date for a QWIP photodetector. To analyze the experimental data, I have modelled the electrical behavior of the QWIP using a small-signal equivalent circuit model.

Download or read book Intersubband Infrared Photodetectors written by Victor Ryzhii and published by World Scientific. This book was released on 2003-06-25 with total page 359 pages. Available in PDF, EPUB and Kindle. Book excerpt: Infrared technologies are very important for a wide range of military, scientific and commercial applications. Devices and systems based on semiconductor heterostructure and quantum well and quantum dot structures open up a new era in infrared technologies.This book deals with various topics related to the latest achievements in the development of intersubband infrared photodetectors, reviewed by top experts in the field. It covers physical aspects of the operation of the devices as well as details of their design in different applications. The papers included in the book will be useful for researchers and engineers interested in the physics of optoelectronic devices as well as their practical design and applications.