Dissertations / Theses on the topic 'Liquid phase epitaxy'
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Gutmann, Roland. "Liquid phase epitaxy of para- and ferroelectric KTa₁-xNbxO₃ /." Zürich, 1993. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=10095.
Full textCheng, Yee Siau. "Development of (Re)BaCuO coated conductors by liquid phase epitaxy." Thesis, University of Cambridge, 2002. https://www.repository.cam.ac.uk/handle/1810/104787.
Full textRomanyuk, Yaroslav. "Liquid-phase epitaxy of doped KY(WO₄)₂ layers for waveguide lasers /." Lausanne, 2005. http://library.epfl.ch/theses/?nr=3390.
Full textKim-Hak, Olivier. "Étude de la nucléation du SiC cubique sur substrats de SiC hexagonaux à partir d’une phase liquide Si-Ge." Thesis, Lyon 1, 2009. http://www.theses.fr/2009LYO10140.
Full textThe aim of this work was to understand the mechanisms that lead to the 3C-SiC formation on hexagonal SiC substrates during the Vapor-Liquid-Solid (VLS) growth from a Si-Ge liquid phase. Our study focused on the early stages of the liquid/SiC interaction, i.e. without reactive gaseous phase (propane) addition. We have shown that 3C-SiC islands were very rapidly formed upon seeds surface. The study of several parameters (such as temperature and duration of the plateau, heating rate, nature of the seed) evidenced the huge influence of the graphite crucible that contains the reaction. Experimental observations combined with thermodynamic calculations show that the most important step for the 3C formation, is the transient reaction between a germanium very rich liquid and the SiC seed. Kinetic effects have to be taken into account to explain the out-of-equilibrium nature of the reaction
Kutter, Michael [Verfasser], and Christian [Akademischer Betreuer] Rohde. "A two scale model for liquid phase epitaxy with elasticity / Michael Kutter. Betreuer: Christian Rohde." Stuttgart : Universitätsbibliothek der Universität Stuttgart, 2015. http://d-nb.info/1068810882/34.
Full textJossen, David. "Flux growth of ZnO microcrystals and growth of doped homoepitaxial ZnO films by liquid phase epitaxy /." Sendai, 2008. http://doc.rero.ch/record/10798?ln=fr.
Full textZhou, Wencai [Verfasser], and C. [Akademischer Betreuer] Wöll. "Thin Films of Porphyrin-Based Metal-Organic Frameworks Grown by Liquid-Phase Epitaxy / Wencai Zhou. Betreuer: C. Wöll." Karlsruhe : KIT-Bibliothek, 2016. http://d-nb.info/1110969651/34.
Full textSon, Ji-Won. "Direct-write e-beam sub-micron domain engineering in lithium niobate thin films grown by liquid phase epitaxy /." May be available electronically:, 2004. http://proquest.umi.com/login?COPT=REJTPTU1MTUmSU5UPTAmVkVSPTI=&clientId=12498.
Full textJaud, Alexandre. "Croissance homo-épitaxiale VLS et étude du dopage au magnésium de GaN pour la protection périphérique de composants de puissance." Thesis, Lyon, 2017. http://www.theses.fr/2017LYSE1181/document.
Full textFor peripheral protection of GaN power electronics devices, we have explored a new approach for performing localized homo-epitaxy of p-doped GaN, by implementing Vapor-Liquid-Solid (VLS) transport. The growth cycle includes three successive steps. At first, Ga is deposited onto the seed surface by MOCVD from TEG, resulting in an array of Ga droplets with submicrometric diameters. Then, Mg is incorporated into the droplets from the gas phase, using (MeCP)2Mg precursor. In the last step, Ga-Mg droplets are nitridated at 500-700°C in flowing ammonia diluted in a carrier gas.After one complete growth cycle, a network of well separated submicrometric GaN dots or ring-shaped features is systematically obtained. Increasing the Mg incorporation into the droplets drastically influences the growth mode, promoting a pure VLS growth mechanism, at the Liquid/Solid interface, versus growth at the triple line. Such GaN structures show a homo-epitaxial relationship with the seed, but a higher crystalline imperfection. Using a multi-cycles approach, GaN films could be obtained, with very high Mg concentrations tunable from 3.1019 to 8.1021 cm-3. Nevertheless, O, C and H impurities are also incorporated at high levels. Various approaches have been vainly investigated to try reducing O contamination level, prohibitive for obtaining p-type material. Actually, as-grown GaN:Mg films are n-type and highly conductive, for moderate Mg concentrations, and become semi-insulating at highest doping levels. Various masking materials have been tested for growth localization purpose
Greenlee, Jordan Douglas. "Study of cation-dominated ionic-electronic materials and devices." Diss., Georgia Institute of Technology, 2014. http://hdl.handle.net/1853/53401.
Full textChoi, Suk. "Growth and characterization of III-nitride materials for high efficiency optoelectronic devices by metalorganic chemical vapor deposition." Diss., Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/45823.
Full textFourreau, Yohan. "Study of the structural properties and defects in CdxHg1-xTe / Cd1-yZnyTe system and investigation of technological improvements for Infrared detection at high temperature." Electronic Thesis or Diss., Paris 6, 2016. https://accesdistant.sorbonne-universite.fr/login?url=https://theses-intra.sorbonne-universite.fr/2016PA066761.pdf.
Full textQuality and stability issues of the images of the matrix components IR cooled with materials II-VI, in particular at high temperature with functioning is critical stakes for Sofradir in a very competitive context. In particular, CdHgTe FPAs are confronted with instabilities in noises of certain pixels, said "blinkers", dominated by a noise type RTS's low frequency (Random Telegraph Signal) difficult to correct. Works show that this specific noise is partially connected to the density of dislocations of the absorption layer, CdHgTe. The improvement of the performances in noise of imagers thus passes by the reduction of the density of dislocations of the alloy CdHgTe.More specifically, these works had for objectives the reduction of the density of dislocations stemming from the plastic relaxation of all or part of the constraints related to the lattice mismatch between the liquid-phase epitaxy (EPL) CdHgTe ( 111 ) B and its CdZnTe substrate.It is shown in these works that the crystalline quality of CdHgTe is situated in the world state of the art when the growths are made in lattice-match conditions (EPD from 9.103 to 5.104 cm-2). The degradation of the crystalline quality of epitaxy is then correlated to the increase of the lattice mismatch substrate-epitaxy, which remains very low (0,1 %). From then on, several solutions, partially stemming from the literature of the systems CdHgTe on If, GaAs or Ge, in strong lattice mismatch (> 13 %), were implemented in these works to limit the formation of misfit dislocations within the CdHgTe layer. In particular, A specific method based on CdHgTe epitaxy was developed to reduce lattice mismatch between the CdZnTe substrate and the CdHgTe epitaxy. The efficiency of this method is estimated since the structural characterization CdHgTe layers, up to the analysis of the electro-optical performances of FPA components.Finally, the problem of the lattice mismatch is approached on a wider frame, in particular via the study of other II-VI-based alloys allowing the realization of lattice-match substrates for CdHgTe. The crystalline quality of these substrates and the realized CdHgTe layers is close to the state of the art. These preliminary conclusions open perspectives of big interest
Bolaños, Rodríguez Western. "Development and characterization of waveguide lasers on monoclinic potassium double tungstates." Doctoral thesis, Universitat Rovira i Virgili, 2011. http://hdl.handle.net/10803/34772.
Full textThe successful combination of the advantages of the waveguide laser geometry and the spectroscopic properties of monoclinic double tungstates was confirmed in this work by the realization of planar and channel waveguide lasers activated with Tm3+. Planar waveguides activated with Er3+ and Tm3+ were fabricated by Liquid Phase Epitaxial growth (LPE) of KY1-x-yGdxLuy(WO4)2 single crystalline layers over KY (WO4)2 substrates. CW and Q-switch laser operation at 1.84 m were, for the first time, demonstrated using the lattice matched composition KY0.58Gd0.22Lu0.17Tm0.03(WO4)2 . Surface channel waveguides were fabricated by structuring the surface of the Er3+ and Tm3+-doped planar waveguides by means of standard UV-photolithography and Ar-ion milling. Buried channel waveguides were fabricated by a novel combination of LPE of the activated layers after structuring of the surface of the KY (WO4)2 substrates by Ar-ion milling. Mirrorles waveguide laser in CW regime was demonstrated using these buried channel waveguides.
Bansen, Roman. "Solution growth of polycrystalline silicon on glass using tin and indium as solvents." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät, 2016. http://dx.doi.org/10.18452/17557.
Full textThe subject of this thesis is the investigation of the growth of polycrystalline silicon on glass at low temperatures from metallic solutions in a two-step growth process. In the first process step, nanocrystalline Si (nc-Si) films are formed either by direct deposition on heated substrates, or by a metal-induced crystallization process, referred to as amorphous-liquid-crystalline (ALC) transition. In the second process step, these seed layers serve as templates for the growth of significantly larger Si crystallites by means of steady-state solution growth. Extensive parameter studies for the ALC process helped to bring down the process duration significantly. Characterization of the nc-Si seed layers, formed by direct deposition on heated substrates, showed that the layer is composed of individual seeds, embedded in a quasi-amorphous matrix. The oxidation of the seed layers prior to the second process step was found to be a major obstacle. The most successful solution has been an initial melt-back step. As the process is hard to control, though, a UV laser system has been developed and installed. First promising results show unobstructed epitaxial growth where the oxide has been removed. Steady-state solution growth on ALC seed layers was found to start from a few larger seed crystals, and then cover the surrounding areas by lateral overgrowth. Although crystallites with sizes of up to 50 micrometers were obtained, it was not yet possible to achieve full surface coverage with a continuous layer. By solution growth on nc-Si seed layers, however, it was eventually possible to achieve this goal. Continuous, polycrystalline Si layers were grown, on which all Si crystallites are interlocked. The growth experiments were accompanied by 3D simulations, in which e.g. different heater configurations have been simulated.
Riva, Federica. "Développement des nouveaux scintillateurs en couche mince pour l’imagerie par rayons-X à haute résolution." Thesis, Lyon, 2016. http://www.theses.fr/2016LYSE1195/document.
Full textX-ray detectors for high spatial resolution imaging are mainly based on indirect detection. The detector consists of a converter screen (scintillator), light microscopy optics and a CCD or CMOS camera. The screen converts part of the absorbed X-rays into visible light image, which is projected onto the camera by means of the optics. The detective quantum efficiency of the detector is strongly influenced by the properties of the converter screen (X-ray absorption, spread of energy deposition, light yield and emission wavelength). To obtain detectors with micrometer and sub-micrometer spatial resolution, thin (1-20 µm) single crystal film scintillators are required. These scintillators are grown on a substrate by liquid phase epitaxy. The critical point for these layers is their weak absorption, especially at energies exceeding 20 keV. At the European Synchrotron radiation Facility (ESRF), X-ray imaging applications can exploit energies up to 120 keV. Therefore, the development of new scintillating materials is currently investigated. The aim is to improve the contradictory compromise between absorption and spatial resolution, to increase the detection efficiency while keeping a good image contrast even at high energies.The first part of this work presents a model describing high-resolution detectors which was developed to calculate the modulation transfer function (MTF) of the system as a function of the X-ray energy. The model can be used to find the optimal combination of scintillator and visible light optics for different energy ranges, and it guided the choice of the materials to be developed as SCF scintillators. In the second part, two new kinds of scintillators for high-resolution are presented: the gadolinium-lutetium aluminum perovskite (Gd0.5Lu0.5AlO3:Eu) and the lutetium oxide (Lu2O3:Eu) SCFs
Giraud, Stephen. "Croissance de couches minces de silicium pour applications photovoltaïques par epitaxie en phase liquide par évaporation du solvant." Thesis, Grenoble, 2014. http://www.theses.fr/2014GRENI057/document.
Full textCrystalline Si thin films on low-cost substrates are expected to be alternatives to bulk Si materials for PV applications. Liquid Phase Epitaxy (LPE) is one of the most suitable techniques for the growth of high quality Si layers since LPE is performed under almost equilibrium conditions. We investigated a growth technology which allows growing Si epitaxial thin films in steady temperature conditions through the control of solvent evaporation from a metallic melt saturated with silicon: Liquid Phase Epitaxy by Solvent Evaporation (LPESE). We studied the main requirements regarding selection of solvent, crucible and growth ambient, and a first experimental set up is designed. An analytical model is described and discussed, aiming to predict solvent evaporation and Si crystallization rate. Growth experiments are implemented with a vertical dipping system. Growth procedure is presented and the influence, on Si growth, of melt convection, temperature gradient in the melt and Si-M reactivity with the material crucible are discussed. Solutions are proposed to improve and optimise the growth conditions. Experimentally, Si thin films were grown from Sn-Si and In-Si solution at temperatures between 900 and 1200°C under high vacuum. We are able to achieve epitaxial layers of several micrometers thickness (20-40µm). The predicted solvent evaporation rate and Si growth rate are in agreement with the experimental measurements. Regarding the structural quality, it is comparable to the crystal quality of layers grown by LPE. With In and In(Ga) melts, we can obtain P-type epitaxial layers with doping level in the range 1017 at.cm3, which is of great interest for the fabrication of solar cells. Finally, the growth of Si thin films on multicrystalline Si substrates by LPESE is discussed to assess the potential application of this technique
Joshi, Chakra Prasad. "Understanding Fundamentals of Plasmonic Nanoparticle Self-assembly at Liquid-air Interface." University of Toledo / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1387306468.
Full textStephan, Pascal. "Contribution a la realisation de composants optoelectroniques integres sur inp." Paris 6, 1987. http://www.theses.fr/1987PA066215.
Full textJoudrier, Anne-Laure. "Hybridation fonctionnelle par transfert de films magnéto-optiques sur guide." Grenoble INPG, 2007. http://www.theses.fr/2007INPG0139.
Full textThis study tries to achieve an integrated hybrid structure, whose function is the optical isolation. This structure is composed of a magneto-optical ferrite garnet layer, chosen for its high Faraday effect, and then bonded on a passive ion-exchanged glass waveguide. Because of technological restraints, the steps are dissociated. The garnet layer is grown by liquid phase epitaxy, without the waveguide thermal restrictions. Then, the garnet is integrated on the waveguide by ionic implantation and direct wafer bonding techniques. The temperatures used in this process are compatible with the waveguide. Moreover, a "test-structure" is realized by wafer direct bonding and mechanical thinning. The comparison between the both structures will show us the effect of the ionic implantation on the magneto-optical properties of the garnet layer
McCann, Michelle Jane, and michelle mccann@uni-konstanz de. "Aspects of Silicon Solar Cells: Thin-Film Cells and LPCVD Silicon Nitride." The Australian National University. Faculty of Engineering and Information Technology, 2002. http://thesis.anu.edu.au./public/adt-ANU20040903.100315.
Full textAznar, Écija Ana Isabel. "Crecimiento y caracterización de capas epitaxiales de KRE 1-X 4BX(WO4)2 /KRE (WO4)2 (RE=Y,LU) para aplicaciones láser." Doctoral thesis, Universitat Rovira i Virgili, 2007. http://hdl.handle.net/10803/9094.
Full textLos cristales monoclínicos de KRE(WO4)2 con RE=Y, Lu, son materiales utilizados como matrices láser de estado sólido debido a que permiten la substitución parcial o total de uno de los iones de su estructura, por otros iones activos en la emisión láser. Además, presentan una elevada estabilidad química. El objetivo de esta tesis ha sido la obtención de capas de Yb:KYW/KYW y Yb:KLuW/KLuW, de elevada calidad para la posterior realización de experimentos láser. El proceso de crecimiento ha sido optimizado con el principal objetivo de conseguir la máxima concentración de ión activo en las capas epitaxiales. Éstas han sido caracterizadas estructural y espectroscópicamente, mostrando resultados prometedores para la emisión láser.
La última parte de esta tesis se ha dedicado al estudio de los experimentos láser, en los que hemos conseguido obtener radiación láser con una longitud de onda alrededor de los 1030 nm con una elevada pendiente de eficiencia, la cual en algunos casos ha excedido las publicadas previamente para los correspondientes monocristales dopados con iterbio.
Keywords: Top Seeded Solution Growth, Liquid Phase Epitaxy, KRE(WO4)2, Materiales láser.
In the past few years, optically active thin layers have attracted much attention due to the possibility of using it in the integrated optics as well as thin disk laser technology. The thin disk laser concept need layers hundreds of microns thick highly doped with active ions and high absorption and emission cross section. The lasers based on thin films have the advantage of high beam quality with high efficiency, making possible to obtain high power with low thermal lensing.
The crystals of the monoclinic tungstates, such as KRE(WO4)2 with RE=Y, Lu, are attractive materials to be used as solid state host doped with lanthanide ions as ytterbium due to the possibility of obtaining highly doped active media.
The aim of this thesis is to investigate how to obtain thin layers of Yb:KYW/KYW and Yb:KLuW/KLuW, with quality enough for laser experiments. The growth process has been optimized in order to obtain crystalline layers with high ytterbium concentration. Structural and spectroscopic properties of these layers have been studied, suggesting that laser emission can be achieved.
The last part of thesis is dedicated to study the laser experiments. We have achieved laser emission around 1030 nm with high slope efficiency, which in some cases exceeded the reported for the ytterbium doped bulk crystals
Keywords: Top Seeded Solution Growth, Liquid Phase Epitaxy, KRE(WO4)2, Laser materials
Wollesen, Laura. "Nouveaux films minces scintillants ultra-denses et solutions alternatives pixélisées pour l'imagerie synchrotron par rayon X." Electronic Thesis or Diss., Lyon 1, 2023. https://n2t.net/ark:/47881/m60k28pm.
Full textThe development of scintillators with high stopping power for high spatial resolution X-ray imaging at synchrotrons has been performed by employing two approaches. The first approach was to grow thin Single Crystalline Films (SCFs) of high density and effective Z number by Liquid Phase Epitaxy (LPE). This is to reach ultimate high spatial resolution while maximizing the absorption efficiency of the films. Before attempting to develop the LPE procedures, the compounds were investigated with a Geant4, Monte Carlo simulation tool combined with subsequent analytical calculations to evaluate their scintillating spatial response. Ultimate high-density compound, Lu2Hf2O7, and other hafnates have in this framework been successfully grown on ZrO2:Y substrates. The atomic structures of the films were confirmed to be iso-structural with the substrate and have a low lattice mismatch. It was experienced that various elements could enter the structure, and a surprising flexibility of the hafnate system for LPE growth is thereby realized. The grown films of Lu2Hf2O7 doped with Europium are discovered to scintillate. However, the substrate itself displays low-intensity emission. The films have a rather low light output but deliver a good spatial response validated by MTFs as well as when performing radiography and tomography. The second approach was to grow state-of-the-art SCF scintillators in a micro-structured manner by LPE. The aim is to increase the stopping power by having tall pillars containing light and maintaining a good spatial response. LSO:Tb and GGG:Eu, were grown micro-structured onto laser-treated LYSO:Ce and GGG substrates, respectively. The morphology of the pillars varies depending on the compound and the substrate orientation. The atomic structures and luminescent properties are comparable to their normal SCF counterparts. Thereby a proof of concept has been demonstrated
Fallahi, Mahmoud. "Intégration hétérogène d'un détecteur N-CdTe à un transistor à effet de champ GaAlAs/GaAs." Toulouse 3, 1988. http://www.theses.fr/1988TOU30188.
Full textLusson, Alain. "Preparation par epitaxie en phase liquide et etude physique des solutions solides cd : :(x)hg::(1-x)te 0,5 <- x <-1." Paris 6, 1987. http://www.theses.fr/1987PA066497.
Full textPELENC, DENIS. "Elaboration par epitaxie en phase liquide et caracterisation de couches monocristallines de yag dope : realisation de lasers guide d'onde neodyme et ytterbium a faibles seuils." Grenoble 1, 1993. http://www.theses.fr/1993GRE10171.
Full textMeyer, Raphaël. "The advanced developments of the Smart Cut™ technology : fabrication of silicon thin wafers & silicon-on-something hetero-structures." Thesis, Lyon, 2016. http://www.theses.fr/2016LYSEI033/document.
Full textAt first, the thesis studies the kinetics of Smart Cut™ in silicon implanted with hydrogen ions for annealing temperature in the range 500°C-1300°C. The kinetics is characterized by using a specially-dedicated furnace and by considering laser annealing. Based on the related characterization and observations, a physical model is established based on the behavior of implanted hydrogen during annealing. The model is strengthened by SIMS characterization focused on the evolution of hydrogen during annealing and on numerical calculations. Additionally, the model proposes an explanation for the properties of the obtained films as a function of the annealing conditions, based on optical microscope and AFM observations and bonding energy characterization. Based on this splitting model, two innovative processes for fabrication of silicon films are proposed. The first process allows to produce films of silicon on sapphire and films of silicon on glass by considering a laser annealing. The second produces foils of monocrystalline silicon by liquid phase epitaxial growth on implanted silicon substrate. The study of the first process proves for the first time the possibility to apply the Smart Cut™ for substrates of implanted silicon. The resulting films present large surface of transferred films (up to 200 mm wafers), which is very interesting in an industrial perspective. The study proposes different characterization of the films obtained by this process (AFM, optical profilometry and 4 probe measurement). The second process is demonstrated by using a chamber of liquid phase epitaxial growth of silicon (deposition temperature superior to 1410°C) in order to deposit liquid silicon on implanted silicon substrates. The obtained films show a high degree of epitaxial growth (up to 90% of the film as characterized by EBSD) and show a thickness as low as 100µm. Additionally the detachment by Smart Cut of the deposited films is demonstrated
Rameix, Armelle. "Réalisation et caractérisation de nouveaux guides d'ondes pour applications laser à 2 microns." Grenoble INPG, 1996. http://www.theses.fr/1996INPG0176.
Full textLekhal, Kaddour. "Le procédé HVPE pour la croissance de nanofils semiconducteurs III-V." Phd thesis, Université Blaise Pascal - Clermont-Ferrand II, 2013. http://tel.archives-ouvertes.fr/tel-00844400.
Full textSreeramakavacham, Bindu. "FILM GROWTH OF NOVEL FREQUENCY AGILE COMPLEX-OXIDE PIEZOELECTRIC MATERIAL." Master's thesis, University of Central Florida, 2007. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/3104.
Full textM.S.M.S.E.
Department of Mechanical, Materials and Aerospace Engineering
Engineering and Computer Science
Materials Science & Engr MSMSE
BEN, YOUSSEF JAMAL. "Elaboration par epitaxie en phase liquide, caracterisation et etude physique des filmsminces de grenats ferrimagnetiques susbstitues par des ions bismuth." Paris 6, 1989. http://www.theses.fr/1989PA066048.
Full textMenaert, Bertrand. "Paramètres physicochimiques régissant la croissance en flux de cristaux de KTiOPO4, isotypes et solutions solides associées : epitaxie en phase liquide." Nancy 1, 1990. http://docnum.univ-lorraine.fr/public/SCD_T_1990_0500_MENAERT.pdf.
Full textBain, Fiona Mair. "Yb:tungstate waveguide lasers." Thesis, University of St Andrews, 2010. http://hdl.handle.net/10023/1698.
Full textTournié, Eric. "Epitaxie en phase liquide des solutions solides GaInAsSb et InAsSbP : application à la réalisation de diodes lasers et photodétecteurs opérant vers 2,5 "mu"m." Montpellier 2, 1990. http://www.theses.fr/1990MON20219.
Full textBerger, Sébastien Laugier André. "Croissance de silicium monocristallin en couche mince par epitaxie en phase liquide sur couches sacrificielles pour report sur substrat faible coût pour applications photovoltaïques." Villeurbanne : Doc'INSA, 2005. http://docinsa.insa-lyon.fr/these/pont.php?id=berger.
Full textSoueidan, Maher. "Croissance hétéroépitaxiale du SiC-3C sur substrats SiC hexagonaux; Analyses par faisceaux d'ions accélérés des impuretés incorporées." Phd thesis, Université Claude Bernard - Lyon I, 2006. http://tel.archives-ouvertes.fr/tel-00136231.
Full textraison du désaccord de maille et de la dilatation thermique. Le SiC-3C peut aussi être déposé sur
substrats SiC-α(0001) en s'affranchissant des problèmes rencontré sur substrat Si. La difficulté de
contrôler la germination initiale génère cependant des macles qui sont difficiles à éviter ou éliminer
ensuite.
L'utilisation de l'épitaxie en phase vapeur comme technique de croissance n'a pas permis de
s'affranchir de ces macles malgré l'optimisation de la préparation de surface des germes SiC- α. En revanche, des couches de SiC-3C exemptes de macle ont été obtenues en utilisant une technique de
croissance originale, les mécanismes vapeur-liquid-solide, qui consiste à alimenter un bain Si-Ge avec
du propane.
La caractérisation des couches ainsi élaborées a montré une excellente qualité cristalline avec toutefois une incorporation non négligeable d'impuretés. Les éléments Al, Ge, B et Sn ont été dosés avec succès en utilisant des analyses par faisceaux d'ions accélérés, techniques peu conventionnelles pour SiC et présentant un challenge analytique.
Douysset, Laurence. "Etude de couches minces monocristallines élaborées par épitaxie en phase liquide pour applications laser dans le visible : croissance et caractérisation de couches de LiYF4 dopé terres rares." Université Joseph Fourier (Grenoble), 1998. http://www.theses.fr/1998GRE10048.
Full textBrassé, Ludovic. "Etude et réalisation d'amplificateurs guides d'ondes appliqués aux microlasers." Université Joseph Fourier (Grenoble), 2000. http://www.theses.fr/2000GRE10196.
Full textSchmatz, Ulrich. "Synthèse par MOCVD de couches supraconductrices d'YBa2Cu3O(7-x) pour des applications en courants forts." Grenoble INPG, 1997. http://www.theses.fr/1997INPG0060.
Full textZaccaro, Julien. "Cristallogénèse et caractérisations de la solution solide dihydrogénophosphate-arseniate de 2-amino-5-nitropyridinium, cristaux organo-minéraux pour l'optique non linéaire." Université Joseph Fourier (Grenoble ; 1971-2015), 1998. http://www.theses.fr/1998GRE10069.
Full textWU, MENG-GI, and 吳孟奇. "Liquid-phase epitaxy of InGaP for luminescent device applications." Thesis, 1986. http://ndltd.ncl.edu.tw/handle/64305198291325006814.
Full textWeng, Yang-Kai, and 翁揚凱. "Characterizations of GaAs layers grown from liquid phase epitaxy." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/36962312061718086188.
Full text中原大學
電子工程研究所
90
To fabricate devices with better electrical and optical characteristics using low ohmic contact resistivity, heavily doped GaAs is required. Germanium is an ideal dopant for LPE because of its low vapor pressure. In this paper, we report on the preparation of highly doped p-GaAs by LPE with the parallel or even higher hole concentrations but with the relatively lower doping amounts of Ge compared with those reported previously. Heavily Ge-doped GaAs single crystal was grown on semi-insulating (100) oriented GaAs by liquid phase epitaxy. Hall effect and photoluminescence (PL) measurements were used to evaluate the quality of the epitaxial layers. The former revealed p-type conductivity of the layers with the hole concentration ranging from 4.7x1018 to 3.8x1020cm-3 and mobility ranging from 3.9 to 204 cm2/V-s while the mole fraction of Ge was varied from 0.138 to 16.3 %. In particular, the carrier concentration of the order of 1019 cm-3 can be easily achieved with only about 1 % of Ge being doped. Additionally, the carrier concentration high to 3.9x1020 cm-3 is obtained with the mole fraction of Ge as low as 16.3 %. The optical properties of the epitaxial layers are correlated with the depletion of free carriers caused by the Ge-doping. The PL peak position shifts to lower energy side with increasing compensation, and the peak energy difference between Ge-doped layer and undoped one is considered to be dominated by band tailing of states and impurity band.
Ming-Fong, Hsieh. "The Study of GaAs Quantum Structures by Liquid Phase Epitaxy." 2006. http://www.cetd.com.tw/ec/thesisdetail.aspx?etdun=U0017-1901200710292301.
Full textCHEN, JIAN-AN, and 陳建安. "AlGaAs/GaAs QUANTUM WELL STRUCTURES GROWN BY LIQUID PHASE EPITAXY." Thesis, 1990. http://ndltd.ncl.edu.tw/handle/13675596858922636584.
Full textHsieh, Ming-Fong, and 謝明峰. "The Study of GaAs Quantum Structures by Liquid Phase Epitaxy." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/40262475533565536624.
Full text中原大學
電子工程研究所
94
In this study, we use bismuth (Bi) as a solvent to grow GaAs homoepilayer by liquid phase epitaxy (LPE). In addition to investigating the optimum condition for homoepitaxy from Bi solution, we also try to grow GaAs quantum structures using a highly super-saturated solution for LPE and its high selective growth capability. The GaAs homoepilayer, grown from the Bi solution with an extremely large super-cooling (ΔT=25 �薡) and with a deliberate doping of germanium (Ge), was found to present the quantum effect for the first time. The surface morphology of epilayers was evaluated by a Normarski differential interference contrast microscope (N-DICM) and cross-sectional views of films were taken by a scanning electron microscope (SEM). It was found that numerous rhomboidal island structures distributing over the surface affected greatly the optical properties of the epilayer. The optical properties of the epilayers were analyzed by photoluminescence (PL) measurements. The luminescent peak of the epilayer was found to shift substantially to 770 nm (Eg=1.61 eV), which is close to that from the GaAs quantum dots with a bulk luminescence band peaking at 870 nm (Eg=1.43 eV). Besides, the peak positions of PL spectra were maintained during the temperature and power dependent PL measurements, suggesting a phenomenon of the quantum confinement effect. Eventually, transmission electron microscopy (TEM) observations presented a direct image of the 4 - 20 nm sized GaAs quantum dots to support our new finding.
CHEN, QI-QING, and 陳啟清. "Liquid phase epitaxy of GaInAsSb/GaSb and heterojunction diode fabrication." Thesis, 1991. http://ndltd.ncl.edu.tw/handle/52938584385496981194.
Full textHuang, Wei-Shuang, and 黃韋翔. "The Study of InAs Heterostructure Grown by Liquid Phase Epitaxy." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/97671580593989761352.
Full text中原大學
電子工程研究所
100
In this experiment we had grown InAs on n-GaAs substrate by liquid phase epitaxy. By adjusting the different growth temperature, growth time, supercooling and change the melt species to get optimal growth conditions. In order to confirm the optimal conditions, we use Hall measurements, X-ray diffraction and SEM to obtain the data. In LPE system, the ratio between melt-solute phase diagram must be known. This experiment we used n-type (1 1 1)-GaAs substrates, pure In for melt (6N) and the fixed weight percent. Trying to change the growth temperture range between 575゚C - 545゚C, and pre-baked at 800゚C for 12 hours, using the supercooling technique with a 5゚C supersaturation; the cooling rate is 0.3゚C per min, and growth time lasts 20 - 60 mins. Although the films surface flatness is poor, but approaching the thermal equilibrium of the LPE growth, can tend to minimize the entropy, so it can get high quality epitaxial layers. From Hall measurements, we get the carrier concentration about 8*1017(cm-3) at 300K and the average thickness is 7.99 um. Further, the X-ray diffraction pattern exhibits the growth plane and indicates the interaction between substrate and crystal epilayer.
SU, TIAN-CAI, and 蘇添財. "1.3^^m InGaAsP/InP DH lasers grown by liquid phase epitaxy." Thesis, 1986. http://ndltd.ncl.edu.tw/handle/39042093498751176493.
Full textKuo, Feng-Jen, and 郭豐任. "The study of GaAs solar cell by liquid-phase-epitaxy technology." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/59221562128589139547.
Full text國防大學中正理工學院
電子工程研究所
95
The purpose of this thesis is to discover the technology of the epilayer of GaAs solar cell and to investigate the material properties of epitaxial layer. III-V compound semiconductors are superior in efficiency, reliability, and radiation-resistivity as compared with silicon, but the cost is the opposite. Many research have discovered that III-V compound semiconductor material, with direct bandgap, are apt to photovoltaic system, so III-V are the best candidate material to develop the high efficiency solar cell. GaAs has the highest conversion efficiency among the III-V compound semiconductor material. Using the low-cost liquid-phase-epitaxy method to fabricate the GaAs solar cell, and build the research potential of military device laboratory. The emphasis of this research is to determine the maximum optical absorption versus the thickness of epitaxial layer of GaAs solar cell. The criteria in determining the thickness of epilayer are growth temperature and growth time. Other parameters are left further confirmed. From the results of experiments, growth temperature and growth time are evitable to affect the quality of epilayer. The purposes of this research are to determine the optimum growth temperature, growth time, and doping concentration, in order to get the mirror-like surface of GaAs epilayer. From the experimental data, the optimum growth temperature to develop the GaAs epilayer is 800℃; impurity doping ratio to develop requisite carrier concentration is 2/1000; appropriate growth time to develop 1μm-thick epilayer is 15 sec; the optimum annealing condition to develop the ohmic contact is at 400℃ for 3 min.
Liu, Zong-Chi, and 劉榮吉. "Liquid-Phase Epitaxy of GaP/AlGaP Double Heterojunction Light- Emitting Diodes." Thesis, 1996. http://ndltd.ncl.edu.tw/handle/52491759696637143547.
Full text國立清華大學
電機工程研究所
84
Recently, visible light sources in the short wavelength region have many attractive applications in full color display, optical information- processing systems such as optical disk memories and optical fiber communication systems with pla- stic fibers. For human vision, the relative eye sensitivity has the maximum value in the location of λ=555nm (pure green light) . Because the large energy gap of GaP is 2.26eV at room temperature, the green radiative recombination may be obser- ved in this material. Near pure green light-emitting diodes have been obtained from GaP/AlGaP double hetero-junction struct- ures. In this paper, we report the growth of n-Al0.3 Ga0.7P, p- GaP and p-Al0.3Ga0.7P epitaxial layers on (111)B GaP sub- strate from a fixed melt composition by LPE technique. At first , we study the electrical and optical properties of undoped-GaP and Al0.3Ga0.7P, then study the epitaxial layers of Te- or Mg- doped GaP and Al0.3Ga0.7P.The lowest carrier concentration of undoped GaP epitaxial layer is 3×1016 cm-3 measured by a mercury probe C-V method. It is grown at 952℃ and cooling rate of 0.5℃/min. The lowest carrier concentration of undoped Al0.3Ga0.7P epitaxial layer is 3.5×1016 cm-3. It is grown at 950℃ and cooling rate of 0.5℃/min.The carrier concentrations of GaP are from 1.6×1016cm-3 to 3×1018 cm-3 for p-type doped and from 2×1017 cm-3 to 2×1018 cm-3 for n- type do- ped, respectively. Finally, we grow three layers in a single run to fabricate double heterojunction p-Al0.3Ga0.7P/p- GaP/n- Al0.3Ga0.7P green LEDs.LEDs are characterized by the cur- rent-voltage (I-V) and electro-luminescence (EL) measureme- nts . A forward-bias turn-on voltage of 1.0447 V with an idea- lity factor of 1.51 are obtained from the current- voltage meas- urements.The wavelength of EL emission peak is around 558 nm at an operating current 20mA at room temperature. The external quantum efficiency of this device is about 4.35×10-3﹪.
Lin, Shih-Po, and 林詩博. "Liquid-Phase Epitaxy of AlGaAs DH and DDH Light-emitting Diodes." Thesis, 1996. http://ndltd.ncl.edu.tw/handle/98428243271107480905.
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