Tesis sobre el tema "Infrared optoelectronics"
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Badioli, Michela. "Graphene optoelectronics from the visible to the mid-infrared". Doctoral thesis, Universitat Politècnica de Catalunya, 2015. http://hdl.handle.net/10803/336097.
Texto completoDesde su descubrimiento en 2004, el grafeno, una sola capa átomos de carbono en un retículo hexagonal, ha atraído un gran interés de la comunidad científica debido a sus propiedades electrónicas, mecánicas y ópticas extraordinarias. Los primeros estudios se centraron en el transporte electrónico, pero en los últimos años estudios en el campo de la fotónica y de las propiedades optoelectrónicas del grafeno han suscitado un mayor interés. El objetivo de esta tesis es explorar el uso del grafeno para nuevos dispositivos optoelectrónicos, adoptando diferentes enfoques para mejorar la interacción del grafeno con la luz en un amplio rango espectral, desde el rango visible hasta el infrarrojo medio. Esto incluye la investigación de la interacción y la transferencia de energía entre un dipolo y una monocapa de grafeno cercana, así como trabajar en esquemas de fotodetección eficientes. La alta movilidad electrónica, la absorción de banda ancha, la flexibilidad y las propiedades optoelectrónicas sintonizables (véase Capítulo 1) hacen que el grafeno sea extremadamente atractivo para el desarrollo de aplicaciones optoelectrónicas con nuevas propiedades funcionalidades. En cuanto a los dispositivos, el punto de partida de los experimentos presentados en esta tesis son transistores de efecto de campo con diferentes geometrías, cuya fabricación y técnicas de caracterización se describen en el Capítulo 2. La capacidad de ajuste de las propiedades optoelectrónicas a través del control de la energía de Fermi es una característica esencial de los dispositivos, y se logra con la aplicación de un voltaje de puerta. Nos dirigimos a ambos aspectos a la base de la optoelectrónica, es decir, el control de las propiedades ópticas con campos eléctricos y la modificación de magnitudes eléctricas, como la corriente con la luz incidente. Por tanto, la primera parte de la tesis (Capítulos 3, 4 y 5) se dedica al estudio de la nanofotónica y plasmónica del grafeno, mientras que la segunda parte se ocupa de fotodetección basada en grafeno (Capítulos 6, 7, 8 y 9). En el Capítulo 3, se explican los principales conceptos del campo de la nanofotónica de grafeno, como la capacidad de ajuste eléctrico y el fuerte confinamiento de los plasmones 2D, así como el acoplamiento de un emisor óptico con los plasmones o pares electrón-hueco. Luego se presentan dos experimentos que muestran el control de la luz por medio de campos eléctricos estáticos. En el Capítulo 4 se muestra el control eléctrico de las vías de relajación de iones de erbio en las proximidades de una monocapa de grafeno: el flujo de energía a partir de los emisores se puede dirigir a pares electrón-hueco en el grafeno, a fotones y a plasmones cambiando el nivel de Fermi del grafeno. En el Capítulo 5 se presenta la excitación y el ajuste de plasmones de grafeno altamente confinados en el infrarrojo medio, activado mediante el dipolo de una punta de microscopia de campo cercano (Capítulo 5). En el Capítulo 6 se revisan los fotodetectores de grafeno existentes y los principales mecanismos que permitan fotodetección con grafeno. A continuación se presentan tres casos donde la fotorrespuesta del grafeno se mejora con la explotación de la interacción con los materiales circundantes. Un fototransistor híbrido de grafeno y puntos cuánticos (véase Capitulo 7) llega a responsividad extremadamente alta en el visible y infrarrojo cercano (más de un millón de A/W). En el Capítulo 8 se demuestra cómo la excitación de fonones de bulk de un sustrato polar aumenta la fotocorriente en el infrarrojo medio a través de un efecto fototermoeléctrico. También fonones superficie del sustrato, lanzados por la iluminación de un borde de metal con luz polarizada perpendicularmente, conducen a un aumento en la fotorrespuesta (Capítulo 9). Los resultados presentados en esta tesis abren nuevos caminos en el campo de la optoelectrónica basada en el grafeno en el campo de la nano-fotónica activa y de los sensores
Cook, Neil B. "Growth and characterisation of pentanary GaInAsSbP Alloys for mid-infrared optoelectronics". Thesis, Lancaster University, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.536032.
Texto completoLivache, Clément. "Quantum-confined nanocrystals for infrared optoelectronics : carrier dynamics and intraband transitions". Electronic Thesis or Diss., Sorbonne université, 2019. http://www.theses.fr/2019SORUS216.
Texto completoColloidal nanocrystals are crystalline objects grown by colloidal chemistry approaches. Thanks to quantum confinement, their optical properties depend on their size, and can then be tuned accordingly. Using mercury selenide and mercury telluride, we grow infrared-absorbing nanocrystals. While HgTe nanocrystals interband gap can be tuned from the NIR to the MWIR, HgSe nanocrystals display self-doping and intraband transitions in the MWIR to LWIR. With a careful control of their surface chemistry, those nanocrystals can be integrated into electrical devices to create cheap infrared photodetectors. In my PhD work, I am interested in probing carrier dynamics in those devices using various time-resolved techniques, either based on photocurrent measurements or on direct observation of the photocarriers relaxation. From dynamic study of HgSe intraband devices, I identify the issue brought by the degenerative doping level of those nanocrystals: transport is driven by the doping of this material, resulting in very poor IR-sensing performances. By taking inspiration from the III-V semiconductor developments, I propose several successful approaches to uncouple optical and transport properties in HgSe-based, MWIR detectors
Norton, Dennis Thomas Jr. "Type-II InAs/GaSb superlattice LEDs: applications for infrared scene projector systems". Diss., University of Iowa, 2013. https://ir.uiowa.edu/etd/5031.
Texto completoDOMINICI, STEFANO. "Numerical investigation of efficiency loss mechanisms in light emitting diodes and determination of radiative and non-radiative lifetimes for infrared optoelectronics". Doctoral thesis, Politecnico di Torino, 2017. http://hdl.handle.net/11583/2669184.
Texto completoDuperron, Matthieu. "Conception et caractérisation de nanoantennes plasmoniques pour la photodétection infrarouge refroidie". Thesis, Troyes, 2013. http://www.theses.fr/2013TROY0030/document.
Texto completoThe market for cooled infrared imaging technologies is growing fast due to a range of applications covering military, commercial and space. Current research for innovative systems focuses on high operating temperature and multispectral detectors.To achieve these aims, optical resonators can be used to concentrate electromagnetic fields in thin absorbing media. This thesis investigates the possibility of using plasmonic resonators for HgCdTe photodetection.Temporal coupled-mode theory is used to optimise analytically the absorption in a plasmonic resonator incorporating an absorbing semiconductor subject to the critical coupling condition. A design of a thin plasmonic HgCdTe diode is then described. This includes a hybrid plasmonic mode arising from the coupling between a surface plasmon and a cavity gap-plasmon mode
Hollingworth, Andrew Roy. "Semiconductor optoelectronic infrared spectroscopy". Thesis, University of Surrey, 2001. http://epubs.surrey.ac.uk/842674/.
Texto completoJollivet, Arnaud. "Dispositifs infrarouges à cascade quantique à base de semiconducteurs GaN/AlGaN et ZnO/ZnMgO". Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLS058/document.
Texto completoThis manuscript focuses on the study and on the development of semiconductor heterostructures based on GaN and ZnO material. These materials are particularly promising for the development of infrared optoelectronic intersubband devices in particular for quantum cascade devices. These semiconductors own several advantages to design quantum cascade devices such as a large conduction band offset and a large energy of the LO phonon. These properties predict the possibility to develop devices covering a large spectral range from near-infrared to terahertz and offer the possibility to realize terahertz quantum cascade lasers operating at room temperature
Giannopoulos, Mihail. "Tunable bandwidth quantum well infrared photo detector (TB-QWIP)". Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2003. http://library.nps.navy.mil/uhtbin/hyperion-image/03Dec%5FGiannopoulos.pdf.
Texto completoThesis advisor(s): Gamani Karunasiri, James Luscombe. Includes bibliographical references (p. 59-61). Also available online.
Cheetham, Kieran James. "GaInAsSbP alloys for mid-infrared optoelectronic devices". Thesis, Lancaster University, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.618809.
Texto completoJiang, Lin. "Investigation of a novel multicolor quantum well infrared photodetector and advanced quantum dot infrared photodetectors". [Gainesville, Fla.] : University of Florida, 2003. http://purl.fcla.edu/fcla/etd/UFE0001249.
Texto completoBéal, Romain. "Laser induced quantum well intermixing : reproducibility study and fabrication of superluminescent diodes". Thèse, Université de Sherbrooke, 2015. http://hdl.handle.net/11143/7728.
Texto completoRésumé : L’intégration de circuit photonique vise à réduire la consommation énergétique, la taille, le coût et les risques de panne des systèmes photoniques traditionnels faits de composants distincts connectés par fibre optique. Cependant, contrairement à la microélectronique, des hétérostructures spécifiques sont requises pour chaque composant : lasers, détecteurs, modulateurs, guides d’ondes… De cette constatation découle le besoin d’une technologie capable de produire des gaufres d’hétérostructures III/V de qualité à plusieurs énergies de gap, et ce de façon reproductible pour un coût compétitif. Aucune des techniques actuelles ne répond pour l’instant pleinement à tous ces impératifs. L’interdiffusion de puits quantique (IPQ) est un procédé post épitaxie basé sur la modification locale de la composition des puits quantiques. L’IPQ induite par laser UV (IPQ-UV) est basée sur l’utilisation de laser excimer (Argon-Fluor émettant à 193 nm ou Krypton-Fluor à 248 nm) pour introduire des défauts ponctuels à la surface de l’hétérostructure. En ajustant la taille du faisceau, sa position, son énergie ainsi que le nombre d’impulsions laser délivrées à la surface du matériau, on peut définir les régions à interdiffuser ainsi que leur futur degré d’interdiffusion. Un recuit de la gaufre active ensuite la diffusion des défauts et par conséquent l’interdiffusion du puits. L’IPQ-UV présente l’avantage considérable de se passer de photolithographie pour définir les zones de différentes énergies de gap, diminuant ainsi la durée et potentiellement le coût du procédé. La reproductibilité de l’IPQ-UV a été étudiée pour l’interdiffusion d’une structure à 5 puits quantiques d’InGaAs/InGaAsP/InP émettant à 1.55 µm. 217 régions sur 12 échantillons ont été irradiés par un laser KrF avec des nombres d’impulsion variables selon les sites et avec une densité d’énergie constante de 155 mJ/cm². Les modifications de la structure générée par ce traitement furent ensuite mesurées par cartographie en photoluminescence (PL) à température ambiante. L’analyse des données montra que l’IPQ-UV permet un contrôle du décalage vers le bleu du pic de PL à +/- 15 % jusqu’à 101.5nm. La température du recuit est apparue comme le paramètre crucial du procédé, puisque la longueur d’onde du pic de PL des zones interdiffusées varie de 1.8 nm par degré Celsius. En considérant les sites irradiés sur une seule gaufre, c’est à dire en s’affranchissant des variations de température entre deux recuits de notre système, la variation du pic de PL est contrôlable dans une plage de ± 7.9%. Ces résultats démontrent le potentiel de l’IPQ-UV en tant que procédé reproductible de production de gaufre à plusieurs énergies de gap. L’IPQ-UV a été utilisé pour la fabrication de diodes superluminescentes (DSLs). Différents type de structure à énergie de gap multiple ont été testés et leurs influences sur les performances spectrales des diodes évalués. Les spectres des DSLs faites de matériau interdiffusé ont atteint des largeurs à mi-hauteur dépassant les 100 nm (jusqu’à 132 nm), ce qui est une amélioration conséquente des ≈ 40nm des DSLs de référence à puissance égale. Les caractéristiques intensité–courant des DSLs interdiffusés furent mesurées comme étant très proches de celle des dispositifs de référence faits de matériau brut, ce qui suggère que l’IPQ-UV n’a pas ou très peu altéré la qualité du matériau initial. Ces résultats prouvent la capacité de l’IPQ-UV à être utilisé pour la fabrication de dispositifs photoniques. Une technique alternative d’IPQ par laser a été évaluée et comparée à l’IPQ-UV pour la fabrication de DSL. Le recuit rapide par laser IR est basé sur l’utilisation simultanée de deux lasers IR pour chauffer localement l’hétérostructure jusqu’à une température suffisante pour provoquer l’interdiffusion: une diode laser haute puissante émettant à 980 nanomètre couplée dans une fibre chauffe la face arrière de la gaufre sur une large surface à une température restant inférieure à celle requise pour provoquer l’interdiffusion et un laser Nd:YAG TEM 00 émettant à 1064 nm un faisceau de 500 µm de large provoque une élévation de température additionnelle localisée à la surface de l’échantillon, permettant ainsi l’interdiffusion de l’hétérostructure. Les dispositifs fabriqués ont montré une augmentation de 33 % de la largeur à mi-hauteur du spectre émis à puissance égale de 1.5 mW. Cependant, l’intensité du pic de PL dans les zones interdiffusées est diminuée de 60 %, suggérant une dégradation du matériau et la difficulté à produire un matériau de qualité satisfaisante.
Taylor, David G. "Development of an infrared optometer thesis submitted in fulfilment of the Postgraduate Diploma in Engineering Research, Auckland University of Technology, 2003". Full thesis. Abstract, 2003.
Buscar texto completoGreen, Alexander Michael. "Resonant-cavity-enhanced optoelectronic devices in the mid-infrared". Thesis, Imperial College London, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.411496.
Texto completoAsghari, Zahra Sadat. "Highf requency optoelectronic devices in the mid infrared wavelength region". Thesis, Sorbonne Paris Cité, 2019. http://www.theses.fr/2019USPCC111.
Texto completoMid infrared (MIR) covers the region of the electromagnetic spectrum between optics and THz ranges. This frequency range is of great interest for applications in spectroscopy and free space optical communications. The progress on unipolar devices based on intersubband transitions, has introduced in the MIR a new family of semiconductor lasers and detectors. These optoelectronic devices are indeed based on optical transitions between electronic states in the conduction band of a complex sequence of quantum wells. Their characteristic lifetime is of the order of picoseconds and therefore intersubband devices have a great potential for wideband ultrafast applications.The aim of this work is the design of a system for high data bit rate free space optical communication in the mid infrared spectral region, with all the components operating at room temperature. To this end, we investigate the high frequency performances of quantum cascade detectors (QCD) and lasers (QCL).Firstly, we carefully explore the electrical and optical characteristics of QCD at 4.9 μm operating at room temperature. A detailed study of the band structure and charge distribution at different operating temperature and under different applied bias is reported. We demonstrate a background limited infrared photodetector (BLIP) temperature of 135 K and a detectivity at this temperature of 2 × 1011 Jones, which is at the state of the art. We then focus on QCD response to high frequency modulation. We engineered and realized an electronic system compatible with high frequency operation. We report an optical response up to 5.4 GHz with a 50 × 50 (μm)2 square mesa using a gold air-bridge technology. Thanks to rectification measurements, we show that the band-pass is limited by the specific detector bandstructure. For the high frequency modulation of QCLs, we develop a plug and play system with an optimization on the injection contact that allows the demonstration of a cut off frequency of 10 GHz, limited by the photodetector. Finally, we present a proof of principle demonstration of a free space optical communication experiment using a QCL and a quantum well infrared photodetector (QWIP) at 4 Gb/s. We use a Binary Phase-Shift Keying (BPSK) modulation technique and we obtain a bit error rate of 10(−5)
Wagner, Brent K. "Molecular beam epitaxial growth of CdTe and HgCdTe for new infrared and optoelectronic devices". Diss., Georgia Institute of Technology, 1991. http://hdl.handle.net/1853/13701.
Texto completoPatin, Benjamin. "Matériaux et Dispositifs optoélectroniques pour la génération et la détection de signaux THz impulsionnels par photocommutation à 1,55µm". Phd thesis, Université de Grenoble, 2013. http://tel.archives-ouvertes.fr/tel-00954635.
Texto completode, la Mare Martin Ian. "Investigation of narrow gap dilute nitride materials for mid-infrared optoelectronic devices". Thesis, Lancaster University, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.587052.
Texto completoFreitas, Felipe Lopes de. "Semiconductors for optoelectronic applications : algaInn alloys for ultraviolet and gesn alloys for infrared photoemission". Instituto Tecnológico de Aeronáutica, 2015. http://www.bd.bibl.ita.br/tde_busca/arquivo.php?codArquivo=3388.
Texto completoLi, Ting. "Gallium nitride and aluminum gallium nitride-based ultraviolet photodetectors /". Digital version accessible at:, 2000. http://wwwlib.umi.com/cr/utexas/main.
Texto completoPlank, Helene [Verfasser] y Sergey D. [Akademischer Betreuer] Ganichev. "Optoelectronic Phenomena Induced by Terahertz/Infrared Laser Radiation in Topological Insulators and Graphene / Helene Plank ; Betreuer: Sergey D. Ganichev". Regensburg : Universitätsbibliothek Regensburg, 2018. http://d-nb.info/1162339772/34.
Texto completoAyoub, Anas. "Sources laser ultrarapides performantes dans le moyen IR et le Tz". Thesis, Normandie, 2020. http://www.theses.fr/2020NORMR044.
Texto completoThe atome probe tomography is an instrument for analyzing matter in three dimensions with atomic resolution. This instrument relies on the effect of an electric field generated at the end of a sample cut into the shape of a nanoscale needle to evaporate the surface atoms which are collected by a two-dimensional detector. The measurement of the time of flight of the ions whose evaporation is triggered by an electrical or optical pulse makes it possible to measure the chemical composition in addition to the 3D localization of the atoms. In current atome probes, atomic evaporation is triggered by a high-speed laser emitting in the UV. However, the interaction of UV light with matter induces thermal heating which limits the mass resolution of the instrument and prevents its use for the analysis of fragile materials such as biocompatible components. This thesis work aims to study solutions to promote rapid evaporation while inhibiting unwanted thermal effects of the laser in atome probe. Our approach consists in exploiting ultrashort pulses in the mid-infrared or THz domain due to their high ponderomotive energy associated with low photon energy. This manuscript reports on the development of a bench for the generation and characterization of intense THz pulses. Coupling these radiations with a negatively polarized metallic nanotip has made it possible to characterize the near field induced at the surface of the nanotip, which is strongly modified by the antenna effect. The second part reports on the development of an ultra-fast laser source tunable in the mid-infrared around 3 mm using fluoride glass fibers
Vannier, Nicolas. "Imagerie polarimétrique active adaptative infrarouge pour des applications de détection et de décamouflage". Thesis, Université Paris-Saclay (ComUE), 2016. http://www.theses.fr/2016SACLO008/document.
Texto completoWe designed and built an active polarimetric imager with laser illumination at 1:55 um wavelength. It cangenerate and analyze any polarization state on the Poincaré sphere. It let us the possibility to perform apolarimetric contrast optimization by analyzing the scene with an ultrafast active-contour-based segmentationalgorithm. This imagins systeme allow to compare several imaging modes having different numbers ofpolarimetric degrees of freedom. We address the detection of manufactured objects in different types ofenvironments with active polarimetric imaging to illustrate the capabilities of the techniques. We demonstratethe effciency of active polarimetric imaging for decamouffage and hazardous object detection, and underlinethe characteristics that a polarimetric imager aimed at this type of application should possess. We show thatin most encountered scenarios the Mueller matrices are nearly diagonal, and suffcient detection performancecan be obtained with simple polarimetric imaging systems having reduced degrees of freedom. Moreover,intensity normalization of images is of paramount importance to better reveal polarimetric contrast
Петров, Дмитро Вікторович. "Технологія оптичних кольорових стекол інфрачервоного діапазону спеціального призначення". Thesis, Національний технічний університет "Харківський політехнічний інститут", 2019. http://repository.kpi.kharkov.ua/handle/KhPI-Press/41528.
Texto completoDissertation for the Ph.D. degree in specialty 05.17.11 – "Technology of refractory nonmetallic materials". – National Technical University "Kharkiv Polytechnic Institute", Kharkiv, 2019. The dissertation is devoted to the development of infrared optical glasses with next spectral characteristics, as well as the creation of technologies for their production. The spectral characteristics are transmittance at a wavelength of 1060 nm 1060 τ (λ₁₀₆₀)>65% and absorption in the spectral range up to 950 nm. The solution to this problem was achieved due to the addition of the Cr₂O₃-Mn₂O₃ colorant system to the glass matrix of the R₂O-PbO-SiO₂ system, as well as the additional optical thin-film coatings. For production implementation optical color glass a pot regenerator furnace was used. The ceramic vessel with a volume of 500 liters was chosen. The temperature of the production was 1420 ± 20 °С. To improve the quality of optical glass practical studies were carried out. These studies devote to the modes of batch filling, mixing and temperature parameters. Fundamental researches were conducted on the mode of cooling of colored optical glass. For the first time for such glasses the stage of cooling made by inertia cooling of the furnace construction without gas. Due to introduction of the results and improving of the spectral parameters the volume of quality glass yield has increased. The software was developed to control the technological processes of the furnace in automatic mode.
Петров, Дмитро Вікторович. "Технологія оптичних кольорових стекол інфрачервоного діапазону спеціального призначення". Thesis, Національний технічний університет "Харківський політехнічний інститут", 2019. http://repository.kpi.kharkov.ua/handle/KhPI-Press/41488.
Texto completoDissertation for the Ph.D. degree in specialty 05.17.11 – "Technology of refractory nonmetallic materials". – National Technical University "Kharkiv Polytechnic Institute", Kharkiv, 2019. The dissertation is devoted to the development of infrared optical glasses with next spectral characteristics, as well as the creation of technologies for their production. The spectral characteristics are transmittance at a wavelength of 1060 nm 1060 τ (λ₁₀₆₀)>65% and absorption in the spectral range up to 950 nm. The solution to this problem was achieved due to the addition of the Cr₂O₃-Mn₂O₃ colorant system to the glass matrix of the R₂O-PbO-SiO₂ system, as well as the additional optical thin-film coatings. For production implementation optical color glass a pot regenerator furnace was used. The ceramic vessel with a volume of 500 liters was chosen. The temperature of the production was 1420 ± 20 °С. To improve the quality of optical glass practical studies were carried out. These studies devote to the modes of batch filling, mixing and temperature parameters. Fundamental researches were conducted on the mode of cooling of colored optical glass. For the first time for such glasses the stage of cooling made by inertia cooling of the furnace construction without gas. Due to introduction of the results and improving of the spectral parameters the volume of quality glass yield has increased. The software was developed to control the technological processes of the furnace in automatic mode.
Yin, Jian. "Novel optoelectronic devices for mid-infrared applications: from intersubband thermophotovoltaic detectors to Germanium nanomembrane light emitters". Thesis, 2016. https://hdl.handle.net/2144/14635.
Texto completo2016-08-17T00:00:00Z
"MBE Growth and Characterization of III-V Bismide Semiconductor Alloys for Mid- and Long-Wave Infrared Applications". Doctoral diss., 2020. http://hdl.handle.net/2286/R.I.62927.
Texto completoDissertation/Thesis
Doctoral Dissertation Electrical Engineering 2020
Anumol, S. "A Study of Synthesis and Optoelectronics of Copper Iron Chalcogenide Nanocrystals". Thesis, 2020. https://etd.iisc.ac.in/handle/2005/4984.
Texto completoAl, Torfi Amin. "Fabrication and Characterization of Optoelectronics Devices Based on III-V Materials for Infrared Applications by Molecular Beam Epitaxy". Thesis, 2012. https://doi.org/10.7916/D8988F2W.
Texto completoSreeshma, D. "Investigations on deep-level defects in HgTe nanocrystals-based photovoltaic devices using a novel instrumentation for Deep Level Transient Spectroscopy". Thesis, 2023. https://etd.iisc.ac.in/handle/2005/6161.
Texto completo"Growth, Optical Properties, and Optimization of Infrared Optoelectronic Materials". Doctoral diss., 2016. http://hdl.handle.net/2286/R.I.39400.
Texto completoDissertation/Thesis
Doctoral Dissertation Electrical Engineering 2016
Lo, Shih-Wei y 羅世為. "Fabrication and Optoelectronic Characterization of InAsPSb/InAs Mid-infrared Photodetectors". Thesis, 2010. http://ndltd.ncl.edu.tw/handle/95305693903876143787.
Texto completo臺灣大學
電子工程學研究所
98
We study the fabrication and the properties of InAsPSb/InAs heterojunction p-i-n (p-InAsPSb/i-InAs/n-InAs) photodetectors. Three structures with different i layer thickness of 0.75 μm (C2759), 1.5 μm (C2758), 2 μm (C2866) were grown by gas source molecular beam epitaxy, and fabricated in devices with four different areas. The responsivity at a wavelength of 3 μm at room temperature increases obviously when the i layer thickness is increased from 0.75 μm to 1.5 μm. But the devices with 2 μm i layer thickness have much lower responsivities because of the large lattice mismatch of the InAsPSb layer. The best performance in our devices is the device with an i layer thickness of 1.5 μm and an area of 500 × 500 μm2. Responsivities at room temperature in the 0.7-1.64 A/W range were obtained in the 2-3.5 μm wavelength range, corresponding to external quantum efficiencies within 50-67 %. If the 65 % transmittance of the surface of the devices is considered, the internal quantum efficiency can be as high as 100 %. And a peak of detectivity of 5.4 × 109 cm-Hz1/2/W was obtained at the wavelength of 3.05 μm. The ideal R0A of our 1.5-um-i-layer samples is 0.77 Ω-cm2. The best detectivity is expected to be 1.67 × 1010 cmHz1/2/W at 3.05 μm with a 100 % quantum efficiency.
Yeh, Tsunghan y 葉宗翰. "Selective Etching Technology Investigated for Optoelectronic Performance of Infrared Photodetector". Thesis, 2011. http://ndltd.ncl.edu.tw/handle/79989894420233975204.
Texto completo國防大學理工學院
電子工程碩士班
99
In this study, we have investigated the selective wet etching technology applied on quantum well infrared photodetector (QWIP) for optical property analysis. The study focused on two major issues: one is the accuracy improvement of the etching process for optical grating pattern and the other is the calculation for absolute responsivity. In addition, we also used the proposed high selectivity etching recipe to remove the FPA substrate to achieve the better thermal imaging. Because the etching depth of optical grating pattern is an important factor for the responsivity of quantum well infrared photodetector, we used selective wet-etching process with etching stop layer to make the etching depth of optical grating pattern more precise. The proposed method not only solves the problem that previous recipe doesn’t work because the depth of our design couldn’t be approached precisely by normal etching solutions but also enhances the spectral response for the QWIP device. Furthermore, we proposed the modified method to achieve the correction factor that converts the relative responsivity measured from Fourier Transform Infrared Spectrometer (FTIR) into the absolute responsivity because the absolute responsivity is an important parameter to assess the QWIP performance. Finally, we used the high selectivity etching recipe to remove the FPA substrate. It solves the problem that the thicker substrate would cause distortion of the optical crosstalk and the delamination between the FPA and ROIC due to thermal stress generated under cooling cycles to result in dead pixels and worse imaging.
Shen-De, Chen. "The Growth and Optoelectronic Properties of InAs/AlGaAs/GaAs Quantum Dot Infrared Photodetectors". 2005. http://www.cetd.com.tw/ec/thesisdetail.aspx?etdun=U0001-0208200513330600.
Texto completoChen, Shen-De y 陳顯德. "The Growth and Optoelectronic Properties of InAs/AlGaAs/GaAs Quantum Dot Infrared Photodetectors". Thesis, 2005. http://ndltd.ncl.edu.tw/handle/43494513336956147773.
Texto completo國立臺灣大學
電機工程學研究所
93
The growth mechanisms of the InAs QDs were investigated by using AFM, SEM, TEM and PL. Phase separation growth of InGaAs cap layer on InAs QDs was also observed. GaAs tends to fill up the valley between InAs QDs whereas InAs is forced to remain on the dots, which leads to longer emission wavelength. The effective quantum well model including strain was developed to calculate the energy levels inside the InAs QD and successfully interpreted the PL spectra. The stress mainly comes from the upper GaAs cap layer rather than the lower GaAs matrix. A QDIP with AlGaAs or InAlGaAs blocking layers was fabricated and analyzed. By introducing a 2 nm Al0.3Ga0.7As cap layer on 3 (2.2) ML InAs QDs, the high-performance narrow-bandwidth multicolor InAs/AlGaAs/GaAs QDIPs were successfully fabricated. The origins of the responses were explained. The negative differential conductance, temperature-dependent and TE-mode-enhanced responses were observed. The negative differential conductance is due to intervalley scatterings. The temperature-dependent response originates from the electronic mobility as a function of temperature. The enhanced TE-mode responses could be engineered by RTA and explained by the transition from the S-like ground state to the strain-induced splitting of P-like first excited states, and the RTA process changes the stress inside InAs QDs due to the bond breaking.
Oye, Michael Mikio. "Effects of plasma species during the molecular-beam epitaxy growth of dilute nitride semiconductors for infrared optoelectronic device applications". Thesis, 2006. http://hdl.handle.net/2152/2844.
Texto completo"High-Quality Extended-Wavelength Materials for Optoelectronic Applications". Master's thesis, 2013. http://hdl.handle.net/2286/R.I.16446.
Texto completoDissertation/Thesis
M.S. Electrical Engineering 2013
Lee, Jheng-Han y 李政暵. "The Epitaxial Growth and Optoelectronic Properties of In(Ga)As Quantum Dot/ Ring Infrared Photodetectors". Thesis, 2013. http://ndltd.ncl.edu.tw/handle/72001095321855518226.
Texto completo國立臺灣大學
電子工程學研究所
101
The Growth mechanism of the In(Ga)As quantum dots (QDs) and rings (QRs) are investigated by the atomic force microscopy, scanning electron microscopy and photoluminescence (PL). Different growth conditions are studied to obtain homogenous QDs and QRs. The uniformity is important especially for quantum dot (QDIPs) and quantum ring infrared photodetectors (QRIPs). For infrared photodetectors, two-color or multi-color, high temperature operation and long wavelength (Terahertz) detection must be achieved to have high performance in responsivity and detectivity. In order to achieve the goals, the surface plasmon combined with QDIP, NH3 plasma treatment passivation, the well in quantum dot stack (WD) structure and QR structures are adopted. The two-color QDIPs are fabricated successfully by the use of top metal contact perforated with the cross metal hole arrays. The periodic contact metal hole arrays play double roles, i.e., the top contact and the optical filter. Patterning with lattice constants a = 1.6 μm and a= 2.8 μm, the 4-6 μm and 8-12 μm wavelength ranges can be detected. Its detectivity can be increased up to 1.85 × 1011 cmHz1/2/W at 20 K and the background limited temperature (BLIP) is between 60-70 K. It can be applied to fabricate the focal plane array (FPA) To achieve high-temperature operation, the performance of AlGaAs/GaAs QWIP and InAs/GaAs QDIP with and without NH3 plasma treatment are investigated. It is demonstrated that the NH3 plasma treatment not only gets rid of the oxide defects such as Ga2O3, As2O3 and As2O5, but also prevents the formation of oxides on the GaAs surface when exposed to atmosphere for one month. It lowers the dark current of QWIP and QDIP. The peak responsivity of the QWIPs without NH3 plasma treatment is 0.48 A/W, and the detectivity is 3.13 × 109 cm-Hz1/2/ W at 1.5 V, and 60 K. However, the QWIP after the 10 minute NH3 plasma treatment exhibits a better performance. The highest operation temperature can be increased from 60 to 90 K. At 90 K, the peak responsivity of the NH3 treated QWIP is 1.25 A/W and the detectivity is 3.54 × 109 cm-Hz1/2/ W at 1.5 V. Similarly, the responsivity of the NH3 plasma treated QDIP enhances from 0.8 to 1.5 A/W at 10 K and from 0.06 to 0.09 A/W at 90 K under the bias of ± 1.5 V and 0.8 V, respectively. The operation temperature also increases from 90 to 140 K. It states the importance of passivation to enhance the device performance. Instead of lowering the dark current, a simple structure of WD-QDIP is proposed which can be operated at a high temperature (~230 K) easily. In traditional QDIPs, the carriers (electrons) are supplied from the top and bottom contacts. In order to achieve high temperature operation, various methods are applied to reduce the dark current. This new design adopts the opposite concept, a QW layer doped with Si to 1017/cm3 is inserted in the middle of a stack of 10 QDs layers to serves as a carrier injection layer to supply carriers to QDs layers quickly and sufficiently. The dark current is increased significantly, however, the photo current (PC) is increased even more. Therefore, the operation temperature can be raised to 230 K. This WD-QDIP achieves a responsivity of 0.046 A/W and the detectivity of 1.26 x 107 cmHz1/2/W under the bias of 0.4 V at 230 K. In addition, the carrier transportation mechanism in this WD-QDIP is studied to reveal the existence of two-channel system, the photovoltaic effect and the presence of the scattered electrons. These phenomena describe and prove how a WD-QDIP can be operated at high temperatures. In these discussion, the scattered QDs and the density of QDs are regarded as the key factors to high-temperature operations. For terahertz detection, an InAs/GaAs quantum ring infrared photodetector (QRIP) has been fabricated successfully. This photodetector demonstrates a cutoff wavelength at 175 μm (1.7 THz) and the detectivity of 1.3×107 cmHz1/2/W at 80 K under the bias of 80 mV. The precise control of the In(Ga)As ring height by capping GaAs layer thickness is responsible for extension of the detector response to terahertz range.
"Chemical Vapor Deposition of Metastable Germanium Based Semiconductors for Optoelectronic Applications". Doctoral diss., 2016. http://hdl.handle.net/2286/R.I.40262.
Texto completoDissertation/Thesis
Doctoral Dissertation Chemistry 2016
Chou, Cheng-Yun. "III-V Semiconductor Materials Grown by Molecular Beam Epitaxy for Infrared and High-Speed Transistor Applications". Thesis, 2016. https://doi.org/10.7916/D8J38SPJ.
Texto completoDai, Jong-Horng. "The Growth and Optoelectronic Properties of In(Ga)As Quantum Ring and its Application in Infrared Photodetectors". 2007. http://www.cetd.com.tw/ec/thesisdetail.aspx?etdun=U0001-1712200719083800.
Texto completoDai, Jong-Horng y 戴忠弘. "The Growth and Optoelectronic Properties of In(Ga)As Quantum Ring and its Application in Infrared Photodetectors". Thesis, 2007. http://ndltd.ncl.edu.tw/handle/33200796551417076107.
Texto completo臺灣大學
電子工程學研究所
96
The growth mechanisms of the In(Ga)As quantum rings (QRs) and its precursors InAs quantum dots (QDs) were investigated by using atomic force microscopy (AFM), transmission electron microscope (TEM) and photoluminescence (PL). The substrate cooling methods on the morphology of surface QDs were studied, it was discovered that turning off power immediately after growth could avoid variation in surface morphology of QDs significantly. Ripening and In adatoms migration results in size redistribution during the QD annealing time, and the elastic relaxation of QDs was also observed. Strain induced In adatoms aggregation to 3D InAs island by annealing was found when the InAs coverage is below critical thickness. The QDIPs with various size QDs were fabricated and analyzed. The detection peak of QDIPs was tailorable from 5 to 10 um. It is because the QD size influences the absorption band of QDIPs. During the growth of QR, dewetting phenomenon occurs when the GaAs capped on InAs QDs are annealed, the thickness of thin GaAs capped layer was sequentially increased to study the strain effect on the transformation of small to large InAs islands to ring structure, and the relationship between the optical properties and morphology was observed. The aspect ratio of InAs QD will affect the shape of In(Ga)As QR. Finally the In(Ga)As/GaAs quantum ring infrared photodetector are analyzed in detail. By employed a thin GaAs layer to tailor the cutoff wavelength of QRIP to 100 um, the terahertz QRIP was fabricated successfully. The mechanism responsible for the far infrared response was explained.