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1
Strickland, Keith R. "Study of ion implantation damage in silicon wafers using phonons." Thesis, Lancaster University, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.332086.
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Bellarmine, P. Xavier. "Simulation of defect nucleation with low energy amorphizing silicon and germanium implants." [Gainesville, Fla.] : University of Florida, 2004. http://purl.fcla.edu/fcla/etd/UFE0006861.
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Fedorov, Alexander Valerievich. "Evolution of point defect clusters during ion irradiation and thermal annealing." Delft, the Netherlands : Delft University Press, 2000. http://books.google.com/books?id=3EVRAAAAMAAJ.
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Pierce, Benjamin Thomas. "Search for Superconductivity in Defect Enhanced Allotropic Carbon Systems." University of Cincinnati / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1384850067.
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Reboh, Shay. "Defect engineering in H and He implanted Si." Phd thesis, Université de Poitiers, 2008. http://tel.archives-ouvertes.fr/tel-00459734.
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Ce travail porte sur l'étude des phénomènes induits par implantation d'hydrogène et/ou d'hélium dans le silicium monocristallin. Le cloquage et l'exfoliation dus à la coimplantation d'hélium et d'hydrogène ont été étudiés en fonction des paramètres d'implantation (énergie, fluence, courant, rapport H/He) et des conditions de recuit. Un comportement de type fenêtre à été observé dont le maximum de surface exfoliée dépend uniquement de la fluence. Deux mécanismes d'exfoliation liés aux régimes de fluence ont été identifiés et discutés. D'autre part, la microstructure des échantillons a été étudié par MET, et les déformations ont été mesurées par diffraction des Rayons X. Un modèle décrivant la distribution des contraintes dans le substrat implanté a été proposé. Le phénomène de delamination des substrats qui apparaît pour des conditions particulières d'implantation a également été étudié, comparé aux phénomènes de cloquage et exfoliation, et expliqué en utilisant des concepts de la mécanique de la fracture. Enfin, l'interaction élastique entre précipités d'He et d'H a été étudiée pour des profils d'implantation superposés et décalés. Dans ce dernier cas, nous avons montré que le champ de contraintes générées par les plaquettes d'hélium en surpression pouvait être utilisé comme source locale de contraintes pour contrôler la formation et la croissance de plaquettes d'hydrogène. Afin d'interpréter nos résultats expérimentaux, nous avons développé un modèle basé sur l'interaction élastique pour la nucléation des précipités dans un solide semi-infini.
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Kummari, Venkata Chandra Sekhar. "A New Approach for Transition Metal Free Magnetic Sic: Defect Induced Magnetism After Self-ion Implantation." Thesis, University of North Texas, 2013. https://digital.library.unt.edu/ark:/67531/metadc271849/.
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SiC has become an attractive wide bandgap semiconductor due to its unique physical and electronic properties and is widely used in high temperature, high frequency, high power and radiation resistant applications. SiC has been used as an alternative to Si in harsh environments such as in the oil industry, nuclear power systems, aeronautical, and space applications. SiC is also known for its polytypism and among them 3C-SiC, 4H-SiC and 6H-SiC are the most common polytypes used for research purposes. Among these polytypes 4H-SiC is gaining importance due to its easy commercial availability with a large bandgap of 3.26 eV at room temperature. Controlled creation of defects in materials is an approach to modify the electronic properties in a way that new functionality may result. SiC is a promising candidate for defect-induced magnetism on which spintronic devices could be developed. The defects considered are of room temperature stable vacancy types, eliminating the need for magnetic impurities, which easily diffuse at room temperature. Impurity free vacancy type defects can be created by implanting the host atoms of silicon or carbon. The implantation fluence determines the defect density, which is a critical parameter for defect induced magnetism. Therefore, we have studied the influence of low fluence low energy silicon and carbon implantation on the creation of defects in n-type 4H-SiC. The characterization of the defects in these implanted samples was performed using the techniques, RBS-channeling and Raman spectroscopy. We have also utilized these characterization techniques to analyze defects created in much deeper layers of the SiC due to implantation of high energy nitrogen ions. The experimentally determined depths of the Si damage peaks due to low energy (60 keV) Si and C ions with low fluences (< 1015 cm-2) are consistent with the SRIM-2011 simulations. From RBS-C Si sub-lattice measurements for different fluences (1.1×1014 cm-2 to 3.2×1014 cm-2) of Si implantation in 4H-SiC, the Si vacancy density is estimated to range from 1.29×1022 cm-3 to 4.57×1022 cm-2, corresponding to average vacancy distances of 4.26 Å to 2.79 Å at the damage peak (50±5 nm). Similarly, for C implanted fluences (1.85×1014 cm-2 to 1×1015 cm-2), the Si vacancy density varies from 1.37×1022 cm-3 to 4.22×1022 cm-3 with the average vacancy distances from 4.17 Å to 2.87 Å at the damage peak (110±10 nm). From the Raman spectroscopy, the implantation-induced lattice disorders calculated along the c-axis (LO mode) and perpendicular to c-axis (TO mode) in 4H-SiC are found to be similar. Furthermore, the results obtained from SQUID measurements in C implanted n-type 4H-SiC sample with fluences ranging from 1×1012 to 1.7×1016 ions/cm2 have been discussed. The implanted samples showed diamagnetism similar to the unimplanted sample. To date, to our best of knowledge, no experimental work has been reported on investigating defect induced magnetism for self-ion implantation in n-type 4H-SiC. These first reports of experimental results can provide useful information in future studies for a better understanding of self-ion implantation in SiC-based DMS.
7
Hickey, Diane P. "Ion implantation induced defect formation and amorphization in the Group IV semiconductors: diamond, silicon, and germanium /." [Gainesville, Fla.] : University of Florida, 2007. http://purl.fcla.edu/fcla/etd/UFE0021224.
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Hirose, Ryo. "Novel molecular ion implantation technology for proximity gettering in silicon wafer for CMOS image sensor." Kyoto University, 2020. http://hdl.handle.net/2433/253278.
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Roth, Elaine Grannan. "Ion-Induced Damage In Si: A Fundamental Study of Basic Mechanisms over a Wide Range of Implantation Conditions." Thesis, University of North Texas, 2006. https://digital.library.unt.edu/ark:/67531/metadc5248/.
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A new understanding of the damage formation mechanisms in Si is developed and investigated over an extended range of ion energy, dose, and irradiation temperature. A simple model for dealing with ion-induced damage is proposed, which is shown to be applicable over the range of implantation conditions. In particular the concept of defect "excesses" will be discussed. An excess exists in the lattice when there is a local surplus of one particular type of defect, such as an interstitial, over its complimentary defect (i.e., a vacancy). Mechanisms for producing such excesses by implantation will be discussed. The basis of this model specifies that accumulation of stable lattice damage during implantation depends upon the excess defects and not the total number of defects. The excess defect model is validated by fundamental damage studies involving ion implantation over a range of conditions. Confirmation of the model is provided by comparing damage profiles after implantation with computer simulation results. It will be shown that transport of ions in matter (TRIM) can be used effectively to model the ion-induced damage profile, i.e. excess defect distributions, by a simple subtraction process in which the spatially correlated defects are removed, thereby simulating recombination. Classic defect studies illuminate defect interactions from concomitant implantation of high- and medium-energy Si+-self ions. Also, the predictive quality of the excess defect model was tested by applying the model to develop several experiments to engineer excess defect concentrations to substantially change the nature and distribution of the defects. Not only are the excess defects shown to play a dominant role in defect-related processing issues, but their manipulation is demonstrated to be a powerful tool in tailoring the implantation process to achieve design goals. Pre-amorphization and dual implantation of different energetic ions are two primary investigative tools used in this work. Various analyses, including XTEM, RBS/channeling, PAS, and SIMS, provided experimental verification of the excess defect model disseminated within this dissertation.
10
Schmidt, Matthias. "Space Charge Spectroscopy applied to Defect Studies in Ion-Implanted Zinc Oxide Thin Films." Doctoral thesis, Universitätsbibliothek Leipzig, 2012. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-84485.
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Die vorliegende Arbeit befasst sich mit der Erzeugung und Detektion von Defekten im Halbleiter Zinkoxyd (ZnO). Der Fokus liegt dabei auf der Verwendung raumladungszonenspektroskopischer Techniken zur Detektion und Charakterisierung elektronischer Defektzustände. Es werden theoretische Aspekte von Raumladungszonen an Halbleitergrenzflächen und den darin enthaltenen elektronischen Defektzuständen behandelt. Das elektrische Potential in der Raumladungszone genügt einer nichtlinearen, eindimensionalen Poissongleichung, für die bekannte, näherungsweise Lösungen vorgestellt werden. Für eine homogen dotierte Raumladungszone gelang es, die exakte Lösung des Potentialverlaufs
als Integral anzugeben und einen analytischen Ausdruck für die Kapazität
der Raumladungszone zu berechnen. Desweiteren werden transiente und oszillatorische Lösungen der Differentialgleichung zur Beschreibung der Zeitentwicklung der Besetzungswahrscheinlichkeit von Defektzuständen für verschiedene experimentelle Bedingungen betrachtet. Sämtliche raumladungszonenspektroskopischen Experimente können durch geeignete Lösungen dieser beiden Differentialgleichungen beschrieben werden. Für die Fälle, für die keine analytischen Lösungen bekannt sind, wurde ein numerisches Modell entwickelt. Die Experimente wurden an ZnO Dünnfilmproben durchgeführt, welche mittels gepulster Laserablation auf Korundsubstraten abgeschieden wurden. Zur Erzeugung von Defekten wurden entweder Ionen in die Proben implantiert, die Proben mit hochenergetischen Elektronen bzw. Protonen bestrahlt oder einer thermischen Behandlung unterzogen. Die Raumladungszonen wurden durch Schottkykontakte realisiert. Durch die raumladungszonenspektroskopischen Verfahren, Kapazitäts-Spannungs Messungen, Admittanzspektroskopie, Deep-Level Transient Spectroscopy (DLTS), Minority Carrier Transient Spectroscopy, optische DLTS, Photokapazitäts- und Photostrommessungen, sowie der optischen Kapazitäts-Spannungs Messung konnten Defektzustände in der gesamten ZnO Bandlücke nachgewiesen werden. Durch Vergleiche der gemessenen Defektkonzentrationen in einer unbehandelten Referenzprobe mit denen in behandelten Proben konnten Aussagen über die experimentellen Bedingungen, unter denen intrinsische Defekte entstehen bzw. ausheilen, gewonnen und mit Stickstoff- bzw. Nickel- in Zusammenhang stehende Defekte identifiziert werden. Für eine Vielzahl untersuchter Defektzustände konnten die thermische Aktivierungsenergie der Ladungsträgeremission, Querschnitte für den Einfang freier Ladungsträger sowie die spektralen Photoionisationsquerschnitte bestimmt werden. Aus diesen Eigenschaften sowie den experimentellen Bedingungen unter denen der Defekt bevorzugt gebildet wird, wurden Rückschlüsse auf die mikroskopische Struktur einiger Defekte gezogen.
11
Klug, Jan N. "Technologie und pysikalische Eigenschaften strahlungsinduzierter Zentren in Silizium." Doctoral thesis, Universitätsbibliothek Chemnitz, 2012. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-82228.
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Die Arbeit beschäftigt sich mit der Erzeugung und den Eigenschaften strahlungsinduzierter Defekte in Silizium. Zur Erzeugung der untersuchten Zentren werden Wasserstoff- und Helium-Ionenstrahlen im MeV-Bereich verwendet. Die Untersuchung erfolgt mittels Spreading-Resistance- und temperaturabhängiger Hall-Messungen.
Betrachtet wird zunächst die Erzeugung einer n-Dotierung durch Wasserstoff-Implantation in Abhängigkeit von Implantationsparametern, - bedingungen und dem Ausheilprozess.
Für Helium-bestrahltes Silizium werden die Auswirkungen der Bestrahlung auf Widerstand, Ladungsträgerkonzentration und Beweglichkeit untersucht.
12
Vieu, Christophe. "Phenomenes de degration et d'amorphisation induits par implantation ionique dans du silicium monocristallin." Toulouse 3, 1987. http://www.theses.fr/1987TOU30279.
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Presentation d'une methode de calcul de la distribution des defauts nes par implantation ionique dans une cible cristalline et inventaire des modeles decrivant la transition cristal amorphe par implantation ionique. Il est montre comment ces travaux theoriques peuvent etre adaptes a la localisation de couches amorphes continues grace a ce calcul de la distribution de defauts. Etude par microscopie electronique en transmission de l'amorphisation a temperature ambiante de si et etude par microscopie electronique par reflexion de la degradation de surfaces atomiquement planes de si par implantation de gaz rares
13
Dalponte, Mateus. "Redistribuição e ativação de dopantes em Si com excesso de vacâncias." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2008. http://hdl.handle.net/10183/15397.
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A redistribuição e ativação elétrica dos dopantes tipo n (As e Sb) e tipo p (Ga e In) em Si com excesso de vacâncias foram analisadas. As vacâncias foram geradas por implantação iônica de altas doses de oxigênio ou nitrogênio em alta temperatura, de acordo com procedimentos já estudados. Em seguida foram implantados os dopantes com dose de 5x1014 cm-2 a 20 keV na região rica em vacâncias. Dopagens idênticas foram realizadas em amostras de Si sem vacâncias e em SIMOX. Em seguida foram feitos recozimentos a 1000ºC por 10 s ou 15 min. Os perfis atômicos dos dopantes foram medidos com Medium Energy Ion Scattering e os perfis dos dopantes ativados, com Hall diferencial. A redistribuição e as propriedades elétricas de cada um dos dopantes no Si sem vacâncias foram bastante similares às observadas no SIMOX, porém várias diferenças foram observadas em relação às amostras com excesso de vacâncias. As vacâncias reduziram a ativação elétrica do As e do Sb, mas proporcionaram maior estabilidade da ativação após recozimentos longos. A redistribuição destes dopantes foi infuenciada pelo íon usado na geração das vacâncias, ou seja, nitrogênio ou oxigênio. O oxigênio proporcionou maior dose retida de As e o nitrogênio, maior dose retida de Sb. Já para o Ga e o In, as vacâncias tiveram papel fundamental na sua redistribuição, diminuindo a difusão para fora das amostras e garantindo maior dose retida. A ativação elétrica do Ga e especialmente a do In foram baixas, onde observamos forte influência do íon pré-implantado, principalmente o oxigênio.<br>The redistribution and electrical activation of n type (As and Sb) and p type (Ga and In) dopants in Si with excess vacancy concentration were analyzed. The vacancies were formed by high dose ion implantation of oxygen or nitrogen at high temperature, following previously studied procedures. Dopants were implanted to a dose of 5x1014 cm-2 at 20 keV in the vacancy rich regions of the samples. Identical doping implantations were performed in bulk Si and SIMOX. Samples were then submitted to thermal annealing at 1000ºC for 10 s or 15 min. The dopants atomic profiles were obtained by Medium Energy Ion Scattering and the active dopant profiles, by differential Hall measurements. The redistribution and the electrical properties of each dopant in bulk Si were similar to those observed in SIMOX, but several differences were observed in the vacancy-rich samples. Vacancies reduced the electrical activation of As and Sb, although the activation was maintained stable after long annealing times. The redistribution of these dopants was, otherwise, dominated by the ion used in the vacancy generation, i.e., nitrogen or oxygen. The presence of oxygen resulted in larger As retained dose, while the presence of nitrogen, in larger Sb retained dose. Regarding the p type dopants, Ga and In, the vacancies played an important role in their redistribution, reducing their out-diffusion and allowing larger retained doses. Ga and especially In electrical activation was low, where strong influence of the pre-implanted ions was observed, especially oxygen.
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Fritz, Serge. "Etude des defauts ponctuels dans le mononitrure d'uranium par diffusion, trempe et canalisation apres bombardement ionique." Université Louis Pasteur (Strasbourg) (1971-2008), 1988. http://www.theses.fr/1988STR13184.
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La nature et le comportement des defauts ponctuels thermiques et des defauts d'irradiation dans le mononitrure d'uranium ont ete etudies. Les defauts thermiques ont ete etudies par trempe et une technique de diffusion de traceur a servi a mesurer la diffusivite de l'uranium. L'effet de la pression d'azote sur l'auto-diffusion de l'uranium suggere un mecanisme lacunaire. Une etude de canalisation et de microscopie electronique d'echantillons implantes avec des ions a permis de comprendre le dommage d'irradiation et sa restauration thermique
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Sarrazin-Baudoux, Christine. "Etude du mixage ionique dans un système à grande limite de solubilité : cas du Cuivre-Nickel, caractérisation de l'adhérence de ces revêtements sur substrat acier." Poitiers, 1987. http://www.theses.fr/1987POIT2305.
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Elaboration de la technique de melange ionique associant l'evaporation de couches minces successives et l'implantation ionique. Etude du melange ionique des multicouches cu-ni. Mise en evidence de deux phenomenes principaux de diffusion en fonction de la temperature. Analyse des phases formees lors du melange ionique. Application de la technique de melange ionique comme procede de depot
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Ryoo, Kunkul. "A study of effect of precipitates and lattice defects on the electrical performance of P-N junctions /." Full text open access at:, 1986. http://content.ohsu.edu/u?/etd,118.
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Harding, Ruth Emma. "Ion implantation defects in silicon studied using the photluminescence technique." Thesis, King's College London (University of London), 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.414828.
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Cristiano, Filadelfo. "Extended defects in SiGe device structures formed by ion implantation." Thesis, University of Surrey, 1998. http://epubs.surrey.ac.uk/843871/.
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The use of SiGe/Si heterostructures in the fabrication of electronic devices results in an improvement of the device performances with respect to bulk silicon. Ion implantation has been proposed as one of the possible technologies to produce these structures and, thus, the aim of this work is to develop an ion beam technology to fabricate strained SiGe heterostructures. The formation of extended defects in SiGe alloy layers formed by high dose Ge+ ion implantation followed by Solid Phase Epitaxial Growth (SPEG) has been investigated by transmission electron microscopy. Rutherford backscattering spectroscopy has also been used to determine the chemical composition and the crystalline quality of the synthesised structures. In addition, X-ray diffraction has been used to evaluate the strain level in selected samples. Two different structures have been studied in this project. The first consisted of "all-implanted" layers, where the Ge+ implants were followed in some cases by additional implants of Si+ and/or C+ ions, prior to SPEG, to investigate methods to inhibit defect formation. The second was achieved by capping the ion beam synthesised SiGe alloy layer by the deposition of a thin film of silicon, in order to realise structures compatible with device dimensions. Single crystal device worthy SiGe alloy layers have been achieved by implantation of Ge+ ions at energies ranging from 70 keV to 400 keV, where the only extended defects observed are EOR defects at a depth correspondent to the a/c interface formed during the Ge+ implant. In some cases, "hairpin" dislocations have also been observed in the vicinity of the EOR defects and extending up to the surface. Both types of defects are annihilated after post-amorphisation with 500 keV Si+ and replaced with dislocation loops at a depth of about 1 fj,m. For each Ge+ implantation energy a critical value of the peak germanium concentration exists above which the structures relax through the formation of stacking faults or "hairpin" dislocations nucleated in the vicinity of the peak of the germanium concentration depth profile and extending up to the surface. A critical value of the elastic energy stored in the structures (~300 mJ/m2) has been determined above which ion beam synthesised SiGe alloys relax, independently of the implantation energy. This empirical approach has been found to successfully account for the results obtained in this work as well as in many other studies reported in the literature. "Hairpin" dislocations formed under different experimental conditions have been investigated by plan view TEM and have been found to have the same crystallographic orientation () and Burgers vector (b= a ). Their formation has been explained within a "strain relaxation model". For a regrowth temperature of 700° C, all samples investigated by XRD have been found to be almost fully strained, including samples containing relaxation-induced defects, indicating that, under these conditions, the energy transferred to the defects is very low. C+ co-implantation has been successfully used to reduce both relaxation-induced defects and EOR dislocation loops. It is noted that a mixed technology entailing both layer deposition and ion implantation to produce the Si/SiGe/Si device structures requires extra process steps to control surface contaminations, pre cleaning and/or native oxide formation, resulting in increased fabrication costs. In this work an " all-implanted" route to the synthesis of Si/SiGe/Si device structures is therefore described, which exploits all of the advantages given by ion implantation.
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Skorupa, Wolfgang, and Gerhard Brauer. "HeT-SiC-05International Topical Workshop on Heteroepitaxy of 3C-SiC on Silicon and its Application to Sensor DevicesApril 26 to May 1, 2005,Hotel Erbgericht Krippen / Germany- Selected Contributions -." Forschungszentrum Dresden, 2010. http://nbn-resolving.de/urn:nbn:de:bsz:d120-qucosa-28591.
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This report collects selected outstanding scientific and technological results obtained within the frame of the European project "FLASiC" (Flash LAmp Supported Deposition of 3C-SiC) but also other work performed in adjacent fields. Goal of the project was the production of large-area epitaxial 3C-SiC layers grown on Si, where in an early stage of SiC deposition the SiC/Si interface is rigorously improved by energetic electromagnetic radiation from purpose-built flash lamp equipment developed at Forschungszentrum Rossendorf. Background of this work is the challenging task for areas like microelectronics, biotechnology, or biomedicine to meet the growing demands for high-quality electronic sensors to work at high temperatures and under extreme environmental conditions. First results in continuation of the project work – for example, the deposition of the topical semiconductor material zinc oxide (ZnO) on epitaxial 3C-SiC/Si layers – are reported too.
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Skorupa, Wolfgang, and Gerhard Brauer. "HeT-SiC-05International Topical Workshop on Heteroepitaxy of 3C-SiC on Silicon and its Application to Sensor DevicesApril 26 to May 1, 2005,Hotel Erbgericht Krippen / Germany- Selected Contributions -." Forschungszentrum Rossendorf, 2005. https://hzdr.qucosa.de/id/qucosa%3A21685.
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This report collects selected outstanding scientific and technological results obtained within the frame of the European project "FLASiC" (Flash LAmp Supported Deposition of 3C-SiC) but also other work performed in adjacent fields. Goal of the project was the production of large-area epitaxial 3C-SiC layers grown on Si, where in an early stage of SiC deposition the SiC/Si interface is rigorously improved by energetic electromagnetic radiation from purpose-built flash lamp equipment developed at Forschungszentrum Rossendorf. Background of this work is the challenging task for areas like microelectronics, biotechnology, or biomedicine to meet the growing demands for high-quality electronic sensors to work at high temperatures and under extreme environmental conditions. First results in continuation of the project work – for example, the deposition of the topical semiconductor material zinc oxide (ZnO) on epitaxial 3C-SiC/Si layers – are reported too.
21
Whiting, Patrick. "Investigation of defects formed by ion implantation of H₂+ into silicon /." Online version of thesis, 2009. http://hdl.handle.net/1850/11814.
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Gong, Min, and 龔敏. "A study of implantation and irradiation induced deep-level defects in 6H-SiC." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1998. http://hub.hku.hk/bib/B3123849X.
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Gong, Min. "A study of implantation and irradiation induced deep-level defects in 6H-SiC /." Hong Kong : University of Hong Kong, 1998. http://sunzi.lib.hku.hk/hkuto/record.jsp?B20567078.
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Ye, Ziran, and 叶自然. "Studies of oxygen implantation induced deep level defects in zinc oxide single crystal." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2011. http://hub.hku.hk/bib/B47153854.
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Zinc Oxide (ZnO)is a wide band gap semiconductor which has attracted great attention because of its wide applicability. In order to obtain semiconductor devices with stable and reproducible properties further study of deep level defects is essential. DLTS (Deep level Transient Spectroscopy) is a direct and straightforward techniqueto determine the energy level of the deep level defects. Other information such as activation energy and capture cross section of the defect can also be obtained through this method. In our study ZnO single crystal samples were implanted by oxygen with the energy of 150keV. After the pretreatment of hydrogen peroxide, Schottky contacts were fabricated with Au
film deposited by thermal evaporation.
Deep level defects were studied by deep level transient spectroscopy (DLTS). Single peak spectra were observed in the as-implanted sample and samples anneal at 350oC, 650oC and 750oC with the corresponding activation energy decreasing with the annealing temperature from ~0.29eV as found in theas-implanted sample. Three peaks were identified in the DLTS spectra of the 900oC sample, with the activation energies of 0.11eV, 0.16eV and 0.37eV respectively.After analysis in detail we found some peaks in the DLTS spectra were the combination of two other peaks, dominated in different temperature range. The thermal evolutions of the deep levels up to the temperature of 1200oC were also investigated.<br>published_or_final_version<br>Physics<br>Master<br>Master of Philosophy
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Cristiano, Filadelfo. "Ion Implantation‐Induced extended defects: structural investigations and impact on Ultra‐Shallow Junction properties." Habilitation à diriger des recherches, Université Paul Sabatier - Toulouse III, 2013. http://tel.archives-ouvertes.fr/tel-00919958.
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This dissertation summarises my research activities in the field of Ion Implantation-Induced extended defects and of their impact on the properties of Ultra-Shallow source/drain junctions (USJs) in miniaturized MOS transistors. The most common method for the fabrication of source/drain regions consists in the localized doping of the substrate material by ion implantation, followed by thermal annealing to achieve electrical activation. The major problem related to the use of ion implantation is the formation of various defect types resulting from the precipitation of the large amounts of interstitials and vacancies generated during the implantation process and their interaction with dopant atoms during annealing. The various complex interactions between the defects and the implanted dopants are at the origin of the diffusion and activation anomalies that represent the major obstacles to the fabrication of USJs satisfying the ITRS requirements. The main results of my work will be presented in three parts. The first part is dedicated to the fundamental studies on the formation and evolution of implant-induced defects and on their impact on transient enhanced diffusion (TED). These studies contributed (i) to provide a unified description of implantation-induced defect evolution, explaining why, depending on the implant and annealing conditions, a given defect type is formed, dissolves during annealing or transforms into a larger defect with different crystallographic characteristics and (ii) to improve the existing models by extending them to all defect families, including a correct TED dependence on the defects' size distributions. In the second part, I will focus on the defect-dopant interactions causing dopant activation anomalies, due to their impact on the active dose and is some cases, also on the carrier mobility. In the case of p+-n junctions formed by Boron implantation, these anomalies are due to the formation of small Boron-Interstitial Clusters (BICs), which will be at the centre of all the studies presented in this part. Other investigated defect-dopant interactions include the formation of Fluorine-related Si interstitial traps, used to reduce both B Transient Enhanced Diffusion and dopant deactivation, and the dopant trapping by implantation-induced defects. The progressive introduction of advanced processes and materials in the semiconductor industry during the last decade raised some specific questions related to the fabrication of USJs, including the formation of implant-induced defects during ultra-fast annealing, their evolution in the presence of the buried Si-SIO2 interface in SOI materials or the Boron activation stability in Germanium. We will address these issues in the third part of this presentation. Due to the increased difficulties to maintain the MOS miniaturization pace (as well as to the approaching of its physical limits), the general context of the MOS-related research domain has largely evolved over the last years. On the one hand, the continuous optimisation of advanced doping and annealing schemes for the fabrication of USJs will therefore have to deal with the increasingly important requirement of reducing power consumption in future device generations. On the other hand, the years 2000s have seen the emergence of the so-called "More-than-More" domain, consisting in the addition of novel functionalities to electronic devices based on (or derived from) Silicon MOS technology. The perspectives of my research activity within this "extended-CMOS" context will finally be presented at the end of the presentation.
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WANG, PING. "CHARACTERIZATION OF SILICON-ON-INSULATOR STRUCTURES FORMED BY ION IMPLANTATION OF OXYGEN (SILICON, DEFECTS, INSULATOR)." Diss., The University of Arizona, 1986. http://hdl.handle.net/10150/183849.
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Silicon-on-insulator (SOI) structures formed in the top region of silicon wafers by ion implantation of oxygen were characterized by RBS (Rutherford Backscattering Spectrometry), OPM (Optical Microscopy), SEM (Scanning Electron Microscopy), and TEM (Transmission Electron Microscopy). Specimens taken from these wafers were previously subjected to specific thermal treatment and silicon epitaxial growth. The results of this investigation show that homogeneous, stoichiometric buried SiO₂ layers were formed beneath the silicon wafer surfaces after high-dose oxygen ion implantation (2.0 x 10¹⁸ O⁺/cm², 180 keV/O⁺). No buried SiO₂ layers were observed in the low-dose wafers (1.0 x 10¹⁷ O⁺/cm², 180 keV/O⁺). Solid-phase epitaxial regrowth (SPE) is strongly temperature dependent. The transition from amorphous (caused by ion impact) to crystalline through the SPE process is completed in the high-dose-rate wafers (∼33 μA/cm²), but not in the low-dose-rate wafers (∼17 μA/cm²). Polysilicon layers were formed on both sides of the SiO₂ layer in the low-dose-rate wafers. Evidence shows that both post annealing (>1000°C, 2 hours in N₂) and in-situ annealing (wafer substrate heating at 500°C during oxygen ion implantation) lower the imperfection density of the top surface region of silicon wafers. A silicon epitaxial layer with low levels of crystalline imperfections was able to be grown on these annealed wafers. The results also show that in-situ annealing is more effective than post annealing. The major microdefects in SOI structures observed in this investigation are dislocations.
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Canino, Mariaconcetta <1980>. "Phosphorus ion implantation in SiC: influence of the annealing conditions on dopant activation and defects." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2007. http://amsdottorato.unibo.it/329/.
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Kucheyev, Sergei Olegovich, and kucheyev1@llnl gov. "Ion-beam processes in group-III nitrides." The Australian National University. Research School of Physical Sciences and Engineering, 2002. http://thesis.anu.edu.au./public/adt-ANU20030211.170915.
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Group-III-nitride semiconductors (GaN, InGaN, and AlGaN) are important for the fabrication of a range of optoelectronic devices (such as blue-green light emitting diodes, laser diodes, and UV detectors) as well as devices for high-temperature/high-power electronics. In the fabrication of these devices, ion bombardment represents a very attractive technological tool. However, a successful application of ion implantation depends on an understanding of the effects of radiation damage. Hence, this thesis explores a number of fundamental aspects of radiation effects in wurtzite III-nitrides. Emphasis is given to an understanding of (i) the evolution of defect structures in III-nitrides during ion irradiation and (ii) the influence of ion bombardment on structural, mechanical, optical, and electrical properties of these materials.
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Structural characteristics of GaN bombarded with keV ions are studied by Rutherford backscattering/channeling (RBS/C) spectrometry and transmission electron microscopy (TEM). Results show that strong dynamic annealing leads to a complex dependence of the damage buildup on ion species with preferential surface disordering. Such preferential surface disordering is due to the formation of surface amorphous layers, attributed to the trapping of mobile point defects by the GaN surface. Planar defects are formed for a wide range of implant conditions during bombardment. For some irradiation regimes, bulk disorder saturates below the amorphization level, and, with increasing ion dose, amorphization proceeds layer-by-layer only from the GaN surface. In the case of light ions, chemical effects of implanted species can strongly affect damage buildup. For heavier ions, an increase in the density of collision cascades strongly increases the level of stable implantation-produced lattice disorder. Physical mechanisms of surface and bulk amorphization and various defect interaction processes in GaN are discussed.
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Structural studies by RBS/C, TEM, and atomic force microscopy (AFM) reveal anomalous swelling of implanted regions as a result of the formation of a porous structure of amorphous GaN. Results suggest that such a porous structure consists of N$_{2}$ gas bubbles embedded into a highly N-deficient amorphous GaN matrix. The evolution of the porous structure appears to be a result of stoichiometric imbalance, where N- and Ga-rich regions are produced by ion bombardment. Prior to amorphization, ion bombardment does not produce a porous structure due to efficient dynamic annealing in the crystalline phase.
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The influence of In and Al content on the accumulation of structural damage in InGaN and AlGaN under heavy-ion bombardment is studied by RBS/C and TEM. Results show that an increase in In concentration strongly suppresses dynamic annealing processes, while an increase in Al content dramatically enhances dynamic annealing. Lattice amorphization in AlN is not observed even for very large doses of keV heavy ions at -196 C. In contrast to the case of GaN, no preferential surface disordering is observed in InGaN, AlGaN, and AlN. Similar implantation-produced defect structures are revealed by TEM in GaN, InGaN, AlGaN, and AlN.
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The deformation behavior of GaN modified by ion bombardment is studied by spherical nanoindentation. Results show that implantation disorder significantly changes the mechanical properties of GaN. In particular, amorphous GaN exhibits plastic deformation even for very low loads with dramatically reduced values of hardness and Young's modulus compared to the values of as-grown GaN. Moreover, implantation-produced defects in crystalline GaN suppress the plastic component of deformation.
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The influence of ion-beam-produced lattice defects as well as a range of implanted species on the luminescence properties of GaN is studied by cathodoluminescence (CL). Results indicate that intrinsic lattice defects mainly act as nonradiative recombination centers and do not give rise to yellow luminescence (YL). Even relatively low dose keV light-ion bombardment results in a dramatic quenching of visible CL emission. Postimplantation annealing at temperatures up to 1050 C generally causes a partial recovery of measured CL intensities. However, CL depth profiles indicate that, in most cases, such a recovery results from CL emission from virgin GaN, beyond the implanted layer, due to a reduction in the extent of light absorption within the implanted layer. Experimental data also shows that H, C, and O are involved in the formation of YL. The chemical origin of YL is discussed based on experimental data.
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Finally, the evolution of sheet resistance of GaN epilayers irradiated with MeV light ions is studied {\it in-situ}. Results show that the threshold dose of electrical isolation linearly depends on the original free electron concentration and is inversely proportional to the number of atomic displacements produced by the ion beam. Furthermore, such isolation is stable to rapid thermal annealing at temperatures up to 900 C. Results also show that both implantation temperature and ion beam flux can affect the process of electrical isolation. This behavior is consistent with significant dynamic annealing, which suggests a scenario where the centers responsible for electrical isolation are defect clusters and/or antisite-related defects. A qualitative model is proposed to explain temperature and flux effects.
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The work presented in this thesis has resulted in the identification and understanding of a number of both fundamental and technologically important ion-beam processes in III-nitrides. Most of the phenomena investigated are related to the nature and effects of implantation damage, such as lattice amorphization, formation of planar defects, preferential surface disordering, porosity, decomposition, and quenching of CL. These effects are often technologically undesirable, and the work of this thesis has indicated, in some cases, how such effects can be minimized or controlled. However, the thesis has also investigated one example where irradiation-produced defects can be successfully applied for a technological benefit, namely for electrical isolation of GaN-based devices. Finally, results of this thesis will clearly stimulate further research both to probe some of the mechanisms for unusual ion-induced effects and also to develop processes to avoid or repair unwanted lattice damage produced by ion bombardment.
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Åberg, Denny. "Capacitance Spectroscopy of Point Defects in Silicon and Silicon Carbide." Doctoral thesis, KTH, Microelectronics and Information Technology, IMIT, 2001. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3205.
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Auberton-Hervé, André-Jacques. "Etude de la faisabilité d'une filière CMOS micronique sur silicium sur isolant." Ecully, Ecole centrale de Lyon, 1986. http://www.theses.fr/1986ECDL0007.
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La première partie de cette étude concerne l'optimisation d'une technique d'élaboration du matériau SOI : la recristallisation par microfusion de zone utilisant un faisceau laser. Les points abordés sont les suivants: la génération de défauts cristallins dans le cadre d'une méthode de germination qui consiste a utiliser le substrat initial comme référence cristalline; la modélisation numérique de l'aspect thermique de la technique de germination; l'interaction entre l'aspect thermique et la croissance cristalline lors de la génération de défauts cristallins ou morphologiques; la mise en place d'une méthodologie de réalisation de dispositifs électriques dans ce type de matériau. Dans une deuxième partie, nous avons développé une modélisation du transistor SOI en couche mince en nous appuyant sur des résultats expérimentaux obtenus à la fois sur le matériau décrit dans la première partie et sur des substrats SOI réalisés par implantation d'oxygène simox. Cette modélisation concerne la tension de seuil, la faible, la forte inversion, les effets de substrat flottant, pour les dispositifs MOS microniques dans le cadre d'un fonctionnement couplé entre l'interface avant et l'interface arrière. Dans la dernière partie, nous présentons les résultats obtenus dans le cadre de la faisabilité d'une filière micronique CMOS sur silicium isolant et les bases de l'optimisation d'une telle filière.
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Gandy, Amy Sarah. "A Transmission electron microscopy study of the interaction betweeen defects in amorphous silicon and a moving crystalline amorphous interface." Poitiers, 2008. http://theses.edel.univ-poitiers.fr/theses/2008/Gandy-Amy/2008-Gandy-Amy-These.pdf.
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Transmission electron microscopy (TEM) has been used to investigate the damage produced following high temperature (350˚C) Xe implantation into [100] Si at fluencies (>1x1016 Xe ions/cm2) and energy (250keV) which produce a buried amorphous layer; and the defect structures produced following thermal anneals of 400˚C, 600˚C or 800˚C for 30 minutes. Analysis of these samples yielded results which suggested that the Xe gas contained within the amorphous layers was swept by the amorphous/crystalline interfaces during solid phase epitaxial re-crystallisation (SPEG) into large bubbles elongated along a direction perpendicular to the interfaces. In order to further investigate this sweeping effect, buried amorphous layers were produced in Si by implanting Li at liquid nitrogen temperature and post implanting the layers with 1x1016 He ions/cm2. Contrary to the spherical bubbles produced under similar conditions in crystalline Si, irregular shaped bubbles were formed in the amorphous layer. Results from in-situ TEM studies showed that these bubbles are mobile at temperatures lower than expected in crystalline Si. Thus, upon reaching the moving interfaces between amorphous and crystalline Si, the bubbles are forced back into the amorphous material which ultimately results in coalescence of the gas into larger bubbles once the two interfaces combine. In addition, microtwins have been shown to form in regions of the re-crystallising layer where there exists an excess of interstitial-type defects. This is contrary to previous microtwin nucleation models which suggested that microtwins are either formed on [111] planes or on bubbles<br>L'endommagement induit par implantation de xénon dans le silicium a été étudié par microscopie électronique à transmission (MET). Les implantations réalisées à 350°C, à une énergie de 250keV et pour des fluences supérieures à >1x1016 Xe ions/cm2 conduisent à la formation d'une couche amorphe enterrée. Les observations effectuées sur les échantillons recuits montrent la présence d'une rangée de grandes cavités allongées dans la direction perpendiculaire à l'interface. Ceci suggère que, lors de la recristallisation du silicium, le déplacement simultané des deux interfaces entraîne le déplacement du gaz jusqu'à son confinement dans de larges bulles. Afin de mieux appréhender les mécanismes qui conduisent au mouvement des bulles, de l'hélium à faible dose a été implanté dans du silicium préalablement amorphisé par implantation de Li à basse température. L'implantation d'hélium dans le silicium amorphe conduit à la formation de bulles de forme irrégulière. Ce résultat diffère du silicium cristallin où des bulles sphériques sont obtenues pour des conditions d'implantation identiques. Les expériences réalisées ‘in situ’ dans le MET montrent clairement d'une part que les bulles sont poussées par l'interface, et d'autre part la nucléation de micromacles. Il a été mis en évidence au cours de cette étude que les bulles sont mobiles à plus basse température dans le silicium amorphe que dans la phase cristalline. Lors de la recristallisation, les bulles se trouvent alors confinées dans le matériel amorphe, ce qui résulte en leur coalescence et à la formation de larges bulles une fois que les deux fronts de recristallisation se sont rejoints. De plus, il a été établi que la formation de micromacles dans la région recristallisée est liée à un excès de défauts de type interstitiels dans la zone amorphe. Ce résultat est contraire aux modèles de la littérature qui suggèrent que les micromacles se forment soit sur des plans {111} soit sur les bulles
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ADEKOYA, OLUSEYI. "Etude du recuit thermique rapide des defauts d'implantation dans le silicium : epitaxie en phase solide et guerison des imperfections residuelles." Paris 7, 1987. http://www.theses.fr/1987PA077265.
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Etude de l'activation electrique des dopants (donneur p; accepteur b) et de l'elimination des defauts residuels dans si monocristallin par recristallisation epitaxique des couches, amorphisees par implantation ionique, et par recuit thermique rapide. Controle de la qualite des couches par retrodiffusion de rutherford et microscopie electronique en transmission et de l'elimination des defauts residuels par la methode dlts (niveau profond a 0,55 ev de la bande de valence). Confirmation de cette elimination des defauts par recuit thermique rapide apres fusion laser de si, avant et apres implantation ionique. Analyse du role electrique des defauts (contraintes thermoelastiques, association impurete-defaut primaire) dans si n, non implante, par des mesures dlts, capacite tension et courant-tension; reduction de leur concentration par depot d'une fine couche d'oxyde
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Schmidt, Florian. "Raumladungszonenspektroskopische Methoden zur Charakterisierung von weitbandlückigen Halbleitern." Doctoral thesis, Universitätsbibliothek Leipzig, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-158772.
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Die Arbeit befasst sich mit der Untersuchung von weitbandlückigen Halbleitern über raumladungszonenspektroskopische Methoden. Dabei liegt der Schwerpunkt auf der Detektion von elektronisch und optisch aktiven Defektzuständen in solchen Materialien. Die Experimente wurden exemplarisch an dem II-VI Halbleiter Zinkoxid (ZnO) durchgeführt, welcher inform von Volumenkristallen, Mikronadeln und Dünnfilmen zur Verfügung stand. Raumladungszonen wurden über Schottky-Kontakte realisiert. Nach einer Einführung in die Theorie der Raumladungszonenspektroskopie wird ein Überblick über Defekte in verschiedenartig gezüchteten ZnO gegeben. Dazu werden die Standardverfahren Strom-Spannungs-Messung, Kapazitäts-Spannungs-Messung, Thermische Admittanz- Spektroskopie (TAS) und Deep Level Transient Spectroscopy (DLTS) verwendet. Ergänzend wurden die auf weitbandlückige Halbleiter ausgelegten Verfahren Low Rate Deep Level Transient Spectroscopy (LR-DLTS) und Deep Level Optical Spectroscopy (DLOS) eingesetzt, mit welchen es möglich ist Defektzustände in der gesamten Bandlücke von ZnO nachzuweisen. Für die untersuchten Störstellenniveaus konnten somit die thermische Aktivierungsenergie, Einfangquerschnitte freier Ladungsträger und Photoionisationsquerschnitte bestimmt werden.
Typischerweise werden tiefe Defekte durch die Bestrahlung mit hochenergetischen Protonen erzeugt. Derartige Behandlungen wurden an binären ZnO- und ternären (Mg,Zn)ODünnfilmen durchgeführt, wobei die Generationsrate eines Defektes über Variation der verwendeten Strahlungsdosis bestimmt wurde. Ionenimplantationen spielen eine große Rolle im Herstellungsprozess von Bauelementen, sind jedoch für ZnO nicht etabliert. Die Auswirkung der Implantation von inerten Argon-Ionen, sowie die nachträgliche thermische Behandlung auf die Konzentration intrinsischer Defekte wurde untersucht. Zink- und Sauerstoff-Implantationen bewirken, neben der Generation von Defekten, eine lokale Änderung der Stöchiometrie. Durch einen Vergleich der Defektkonzentrationen nach Zn-, O-, Ne- und Ar-Implantation können Rückschlüsse auf die chemische Natur intrinsischer Defekte geschlossen werden.
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Hardie, Christopher David. "Micro-mechanics of irradiated Fe-Cr alloys for fusion reactors." Thesis, University of Oxford, 2013. http://ora.ox.ac.uk/objects/uuid:a3ac36ba-ca6f-4129-8f37-f1278ef8a559.
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In the absence of a fusion neutron source, research on the structural integrity of materials in the fusion environment relies on current fission data and simulation methods. Through investigation of the Fe-Cr system, this detailed study explores the challenges and limitations in the use of currently available radiation sources for fusion materials research. An investigation of ion-irradiated Fe12%Cr using nanoindentation with a cube corner, Berkovich and spherical tip, and micro-cantilever testing with two different geometries, highlighted that the measurement of irradiation hardening was largely dependent on the type of test used. Selected methods were used for the comparison of Fe6%Cr irradiated by ions and neutrons to a dose of 1.7dpa at a temperature of 288°C. Micro-cantilever tests of the Fe6%Cr alloy with beam depths of 400 to 7000nm, identified that size effects may significantly obscure irradiation hardening and that these effects are dependent on radiation conditions. Irradiation hardening in the neutron-irradiated alloy was approximately double that of the ion-irradiated alloy and exhibited increased work hardening. Similar differences in hardening were observed in an Fe5%Cr alloy after ion-irradiation to a dose of 0.6dpa at 400°C and doses rates of 6 x 10<sup>-4</sup>dpa/s and 3 x 10<sup>-5</sup>dpa/s. Identified by APT, it was shown that increased irradiation hardening was likely to be caused by the enhanced segregation of Cr observed in the alloy irradiated with the lower dose rate. These observations have significant implications for future fusion materials research in terms of the simulation of fusion relevant radiation conditions and micro-mechanical testing.
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Pokam, Kuisseu Pauline Sylvia. "Détachement des substrats ultra-minces des matériaux semi-conducteurs par implantation d’hydrogène à hautes énergies pour les applications photovoltaïques et électroniques." Thesis, Orléans, 2016. http://www.theses.fr/2016ORLE2035/document.
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Cette thèse a été motivée par l’étude d’un procédé innovant de production de substrats ultra-minces (d’épaisseur variant de 15 μm à 70 μm), basé sur l’implantation d’hydrogène à haute énergie, dans notre cas comprise entre 1MeV et 2.5MeV. Une telle implantation suivie d’un traitement thermique approprié, conduit au détachement d’un film mince autoporté, appelé « substrat ultra-mince ». L’intérêt de ce procédé de détachement est purement économique, car il ne génère presque aucune perte de matière première. Nous l’avons particulièrement utilisé pour produire des substrats ultra-minces de silicium (100), pour la production des cellules PV bas-coûts. Dans le but d’élargir les champs d’applications du procédé, le détachement de substrats ultra-minces de deux autres matériaux (le Ge et le SiC) très utilisés en électronique a aussi été étudié. Ainsi, dans cette étude, les paramètres optimaux d’implantation (énergie et fluence) et de recuits conduisant au détachement de grandes surfaces de Si(100) ont tout d’abord été investigués. Ensuite, l’application technologique du procédé proposé a été validée par la réalisation des cellules solaires au moyen des substrats ultrafins de Si détachés (50 μm et 70 μm d’épaisseur). Les performances PV obtenues ont été assez proches de celles obtenues avec une cellule référence réalisée sur un substrat standard. Par la suite, une étude détaillée faite par TEM et par FTIR sur les défauts étendus à différents stades de recuits a permis de mettre en lumière la nature et la distribution spatiale des défauts précurseurs de la fracture dans le Si après implantation à haute énergie. Enfin, des essais de détachements réalisés avec le Ge et le SiC, lesquels ont été comparés au cas du Si, ont permis d’en savoir plus sur les critères de détachement. En effet, plus le matériau sera rigide, i.e. plus il aura un module d’Young élevé, plus la fluence et la température de recuit nécessaires pour le détachement seront élevées<br>The motivation of this thesis was the study of an innovative process for the production of ultra-thin substrates (with thicknesses between 15 μm and 70 μm), based on the high energy hydrogen implantation, in our case in the range of 1 MeV to 2.5 MeV. Such an implantation followed by an appropriate thermal annealing, lead to the delamination of a freestanding thin layer, that we call “ultra-thin substrate”. The benefit of this delamination process is purely economic, since almost no raw material is lost. We have particularly used this process to produce ultra-thin (100) Si substrates, for the production of low-cost PV solar cells. In order to extend the process application fields, the delamination of ultra-thin substrates of two other materials (Ge and SiC) widely used in electronics has been also studied. In our work, the optimal implantation parameters (energy and fluence) and thermal annealing, leading to the delamination of large areas of Si (100) were first investigated. Subsequently, in order to validate the technological application of our process, solar cells have been performed with ultra-thin silicon substrates delaminated, with thicknesses of 50 μm and 70 μm. Results of PV performances obtained were quite close to those obtained with a reference solar cell achieved on a standard substrate. After that, in order to highlight the nature and the spatial distribution of fracture precursor defects after high energy hydrogen implantation in silicon, which had not yet done so far the subject of specific studies, characterizations have been carried out at different annealing stages, by means of TEM and FTIR. Finally, delamination results obtained with Ge and SiC, which were compared to the case of Si, helped us to learn more about delamination criteria. Indeed, we observed that, as the material rigidity increase, i.e. as the Young modulus is higher, the fluence and temperature require for the delamination will be also high
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Pingault, Timothée. "Etude pionnière combinant l’implantation d’hydrogène et la fracture induite par contrainte pour le détachement de couches ultra-minces de silicium pour le photovoltaïque." Thesis, Orléans, 2016. http://www.theses.fr/2016ORLE2048/document.
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La motivation de cette thèse est la production innovante de germes ultra-minces de silicium cristallin. L’utilisation de tels germes dans un procédé de fabrication de cellules solaires permettrait une réduction importante de la consommation de silicium, qui compte déjà pour 60% du coût de production des panneaux solaires de première génération. Dans le cadre de cette thèse, une méthode pionnière de détachement de germes minces a été mise en oeuvre. Dans cette méthode, une contrainte induite mécaniquement est guidée par des défauts étendus induits par l’implantation d’hydrogène. Par cette méthode, le détachement de germes minces d’environ 710nm d’épaisseurs a été obtenu. Le but est ensuite d’utiliser ces germes pour faire croitre du silicium cristallin avec des épaisseurs variables à souhait, soit une technique kerf-free : sans pertes. Cette étude présente ainsi les étapes menant à la mise en oeuvre de ce procédé : en premier lieu, un état de l’art des méthodes de détachement de films ultra-minces existants est réalisé. Celui-ci nous a ainsi guidés vers l’implantation d’hydrogène en tant que méthode viable du guidage de la fracture. Par la suite, différents tentatives de détachement de germes ultra-minces ont été réalisés puis caractérisés, notamment par MEB, MET, AFM et DRX. Dans de bonnes conditions de collage et de croissance de défauts, le détachement de germes ultra-minces de silicium cristallin a été réalisé. Par la suite, la croissance et la cristallisation de couches de silicium amorphe a été réalisée sur les germes détachés. Pour finir, certaines couches détachées ont été utilisées pour la production de cellules solaires prototypes<br>The goal of this thesis is to find an innovative way to produce ultra-thin crystalline silicon seeds. The use of such seeds in a solar cell production process could lead to a significant reduction of the silicon consumption, which cost alone is worth 60% of the total cost of a first generation solar panel. Within the context of this PhD thesis, a pioneer seed exfoliation method was implemented. This method use the defects induced by hydrogen implantation to guide a stress-induced spalling process. This method has allowed the exfoliation of 710nm-thick crystalline silicon seeds. These seeds will then be used for the growth of crystalline silicon layers of any desired thickness, hence a totally kerf-free method. This thesis work presents the steps leading to the implementation of this process: firstly, the state of the art of ultra-thin films exfoliation methods is reviewed, which guided us towards the use of hydrogen implantation as a crack guide. Then, different ultra-thin seeds exfoliation processes were tried and characterized, specifically by SEM, TEM, AFM and XRD. In the right conditions of bonding and defects growth, ultra-thin silicon seeds were successfully exfoliated. The growth and crystallization of amorphous silicon layers on these seeds were then studied. Finally, several exfoliated layers were used for the production of prototype solar cells
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Vallet, Maxime. "Étude des défauts bidimensionnels à base d'hélium dans le silicium - Application au transfert de films minces." Thesis, Poitiers, 2014. http://www.theses.fr/2014POIT2277/document.
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Le procédé Smart CutTM, utilisé pour le transfert de films minces sur substrat est basé sur la fissuration du silicium. La propagation des fissures est initiée à partir de défauts bidimensionnels induits par implantation d'hydrogène, les « H-platelets ». Des études précédentes ont montré que la fissuration du Si peut également être obtenue à partir de défauts nommés « He-plates » qui ont la particularité d'avoir un diamètre dix fois supérieur. L'objectif de ce travail était d'étudier la formation de ces défauts et leur évolution sous flux d'hydrogène jusqu'à la propagation des fissures. Dans une première partie, la formation des « He-plates » a été étudiée pour différentes orientations de substrats et discutée par rapport à la contrainte compressive bi-axiale induite par l'implantation. Les résultats montrent que les mécanismes qui gouvernent la formation des « He-plates » sont les mêmes que pour les « H-platelets ». Dans une seconde partie, l'évolution des « He-plates » en présence d'H a été étudiée en utilisant une approche expérimentale originale qui couple implantations d'hydrogène et observations par microscopie électronique en transmission. Les expériences montrent que la croissance des « He-plates » est gouvernée par la diffusion de l'hydrogène qui dépend de la température et du taux d'endommagement. Enfin, leur croissance est décrite à l'aide d'un modèle cinétique et, leur coalescence a été analysée en relation avec un modèle élastique. La propagation rectiligne de fissures à partir de ces précurseurs offre des perspectives intéressantes pour une utilisation industrielle<br>The Smart CutTM process, used in the transfer of thin films on substrates is based on the cracking of silicon. The crack propagation is initiated from bi-dimensional defects induced by H-implantation, the H-platelets. Previous studies showed that the propagation of cracks in Si can also be triggered from defects named He-plates which have the particular feature of having a diameter ten times larger. The aim of this work was to study the formation of these defects and their evolution until the crack propagation under H supply.In a first part, the formation of He-plates was studied for different substrate orientations and discussed regarding the bi-axial compressive stress induced by implantation. Results show that the mechanisms that govern the He-plate formation are the same than for H-platelet formation. In a second part, the evolution of He-plates under H supply was studied by using an original experimental approach that combines H-implantation and transmission electron microscopy observations. Experiments show that the growth of He-plates is controlled by the diffusion of hydrogen which depends on temperature and damage rate. Finally, the growth is described by a kinetic model and their coalescence was analyzed with regard to an elastic model. The straight propagation of cracks from He-plates offers promising outlook for an industrial use
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Lagrange, Jean-Pierre. "Contribution à l'étude du dopage bore, azote et phosphore dans le diamant." Université Joseph Fourier (Grenoble), 1997. http://www.theses.fr/1997GRE10210.
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Le diamant est un semi-conducteur a large bande interdite (5. 4 ev) tres prometteur en electronique a haute temperature et de forte puissance. Cependant, son utilisation est limitee par l'absence d'un dopage de type n. Nous avons etudie dans cette these le dopage au bore du diamant (type p), et l'incorporation de phosphore et d'azote dans le diamant par implantation ionique. Nous avons elabore des couches minces de diamant par depot chimique en phase vapeur assiste par plasma micro-onde. Nous avons utilise dans notre etude diverses techniques de caracterisation : spectroscopie de diffusion raman, resonance paramagnetique electronique, resistivite en fonction de la temperature (de 100k a 1000k), effet hall, courants thermo-stimules, thermoluminescence. Les resultats obtenus montrent que le dopage au bore est aujourd'hui bien maitrise. Des mesures electriques sur une large gamme de concentration (de 5 10#1#6 a 8 10#2#0 b. Cm#-#3) montrent trois regimes de conduction differents : conduction par saut par plus proche voisin, conduction par la bande de valence, conduction metallique. Nous avons montre pour la premiere fois une saturation de la conductivite et une energie d'activation a haute temperature e#a/2 typique d'un taux de defauts compensateurs inferieur a 10%. Nous avons montre que l'implantation est la methode la plus efficace pour incorporer de l'azote en site substitutionnel dans le diamant. Neanmoins, l'incorporation d'azote semble induire indirectement des defauts paramagnetiques dans le diamant. Nous avons aussi montre que l'incorporation de phosphore en site substitutionnel est possible. Nous avons defini un seuil d'amorphisation compris entre 3 et 4 10#1#4 p. Cm#-#2. Toutefois, un nouveau defaut paramagnetique qui semble etre induit par le phosphore apparait apres recuit. La conduction est encore dominee par les defauts crees par l'implantation ionique. Ces resultats sont tres prometteurs pour des applications futures en microelectronique.
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Khan, Rizwan Uddin Ahmad. "Electronic properties of hydrogenated amorphous carbon thin films." Thesis, University of Surrey, 2001. http://epubs.surrey.ac.uk/844559/.
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This thesis is concerned with the growth, electronic properties and modification of hydrogenated amorphous carbon films of a thickess range of 50-300 nm, which have been deposited using rf plasma-enhanced chemical vapour deposition. These films may be subdivided into two types according to the electrode on which they are grown and the resulting film properties. These are polymer-like amorphous carbon or PAC, and diamond-like amorphous carbon or DAC. PAC possesses a wide optical band gap (2.7 eV), high resistivity (1014 - 10 15 Ocm) and low density of paramagnetic defects (~ 10 17 spins cm-3). The dominant current transport mechanism at room temperature has been observed to be hopping conduction at low electric fields and space-charge-limited current at high electric fields. The addition of nitrogen gas to the plasma to incorporate nitrogen within the film has been shown to move the Fermi level by 1 eV, towards midgap. A mechanism of doping due to the introduction of aromatic nitrogen-containing sites has been postulated. The boron, carbon and nitrogen ion implantation of PAC has resulted in the controllable increase in conductivity from 1015 to 106 O cm as a function of ion dose, from 2 x 1012 to 2 X 1016 ions cm-2. At low ion doses (up to 6 x 1014 ions cm-2) this occurs without any change in band gap; however, at higher doses the band gap collapses as a result of graphitisation. The dependence on the implant ion shows that it is possible to move the Fermi level towards the valence band with the implantation of boron, and towards midgap with the implantation of nitrogen. A hysteresis effect is observed at intermediate ion doses, which is attributed to the trapping of holes resulting in an increase in electron current. Implanting part of the thickness of the film at this ion dose has resulted in rectification, which has not previously been reported for this type of structure in amorphous carbon. DAC has been shown to possess a smaller band gap (0.7 eV), higher density of defects (~ 1020 spins cm-3) and lower resistivity (~ 1013 O cm) than PAC. The room-temperature current transport is governed by band-tail conduction at fields below 105 V cm-1, and the Poole-Frenkel effect at higher fields. The addition of nitrogen of up to 8 at. % has been observed to increase the band gap from 0.7 to 1.0 eV and therefore decrease the magnitude of the Poole-Frenkel conductivity. The Fermi level remains pinned at midgap, however. Therefore, it appears that PAC shows advantages over DAC in terms of future device applications.
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Pentecoste, Lucile. "Etude de la formation de défauts lacunaires dans un cristal de tungstène par accumulation d’hélium." Thesis, Orléans, 2015. http://www.theses.fr/2015ORLE2040/document.
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Le tungstène sera soumis à des conditions extrêmes de température et de bombardement de particules en tant que paroi des cibles du divertor dans le réacteur de fusion nucléaire ITER. De hauts flux d’ions légers impacteront la surface du tungstène et sont susceptibles de générer des défauts dans le cristal. Cette étude vise à étudier les premières étapes de la formation des défauts lacunaires dans le cristal de tungstène soumis à un faible flux d’ions de faible énergie afin de comprendre le rôle de l’accumulation de l’hélium, un des produits de la réaction de fusion du deutérium et du tritium. Pour cette étude, une source plasma ICP-RF a été développée et qualifiée afin de réaliser des implantations d’hélium dans des conditions parfaitement contrôlées. Les implantations d’hélium ont été réalisées pour plusieurs conditions de fluence, d’énergie et de température, sur des échantillons de tungstène polycristallins. La spectroscopie d’annihilation des positons a été utilisée pour caractériser les défauts lacunaires, les analyses par réactions nucléaires, pour quantifier l’hélium implanté et la spectrométrie de thermodésorption pour caractériser les interactions de l’hélium dans le cristal. Les résultats montrent que pour une énergie de 320 eV à température ambiante, une fluence incidente limite est atteinte à partir de laquelle une saturation de l’hélium implanté apparaît et la formation de lacunes de grande taille débute. L’étude de l’influence de l’énergie et de la température montre l’importance de la répartition de l’hélium en profondeur et de sa mobilité dans le cristal sur la taille et la diversité des défauts formés. Les implantations sont simulées par dynamique moléculaire. Les résultats obtenus par l’approche numérique sont comparés aux résultats expérimentaux afin de mieux comprendre les mécanismes élémentaires mis en jeu<br>Tungsten will be exposed to severe plasma conditions such as high temperature and high particle bombardment as a target of the divertor in the nuclear fusion reactor ITER. High fluxes of light ions will impact its surface and can generate defects in the crystal. This study means to observe the first steps of the vacancy-type defects formation in the tungsten crystal subject to low ion flux of low kinetic energy in order to understand the influence of the accumulation of helium, one of the nuclear reaction products. For the experiments, an ICP-RF plasma source was developed and characterized to perform helium implantations under perfectly controlled conditions. Helium implantations were performed under various conditions of fluence, energy and substrate temperature on polycrystalline tungsten samples. Positron annihilation spectroscopy was used to characterize vacancy-type defects, nuclear reaction analysis to quantify implanted helium and thermal desorption spectrometry to characterize the interactions of helium in the crystal. Results show that, for a kinetic energy of 320 eV and at room temperature, a saturation of the helium implanted quantity is reached for a limit incident fluence and that large vacancy defects starts to form. Study of the kinetic energy and the surface temperature influences show the importance of the depth distribution and the mobility of the helium in the crystal on the size and the diversity of the generated defects. Implantations are performed by molecular dynamic simulations. Results obtained by the numerical approach are compared to experimental ones in order to get a better understanding of the atomic scale mechanisms
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Dezillie, Britta. "Étude de la tenue aux radiations de détecteurs de particules en silicium épitaxial pour leurs utilisaitons au LHC du CERN." Université Joseph Fourier (Grenoble ; 1971-2015), 1997. http://www.theses.fr/1997GRE10146.
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Dans les experiences futures dans le lhc de cern on veut utiliser des detecteurs de silicium de haute precision. Le composent hadronique influence le temps de vie des detecteurs. La tenue aux irradiations du silicium peut etre amelioree par l'etude des defauts. Cette etude implique l'addition des impuretes au silicium afin de former des centres de defauts qui sont actives d'une maniere electrique. Ceux ci controlent les parametres macroscopiques des echantillons. Les ingredients principales a examiner sont l'oxygene et le carbone parce qu'ils se comportent comme consommateurs des vacances et des interstitials. Un premier essai a introduire du ge dans le silicium a ete realise. Du materiel epitaxiale du type n de macom (us) qui contient dix fois plus d'oxygene que le float-zone (fz), montre une amelioration d'un facteur 2 a l'egard du fz. Les impuretes initiales au sein du materiel ont ete mesurees par sims et spectrometrie infrarouge (ir). Les etudes d'irradiations des detecteurs epitaxiales du type n et p avec une epaisseur de 200 m, produits par itme (pologne) avec differentes vitesses de croissance, sont reportees dans ce travail. Une comparaison de differents procedes comme l'implantation par ionisation et mesa a ete faite. La tenue aux irradiations des detecteurs de silicium epitaxials avec des resistivites initiales de 25 ohm cm a 10 kohm cm a ete comparee avec du fz standard. Les resultats sont presentes en terme de la variation du courant de fuite, la concentration de dopage effectif et la collection de charge en fonction de la fluence et le temps apres des irradiations proton en neutron jusqu'une fluence de 4. 5 10#1#4 p/cm#2.
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Asplet, William. "Etude des interactions entre les défauts lacunaires et les solutés Y,O, Ti pour mieux comprendre leur rôle dans la formation des nanoparticules d'oxydes dans les aciers ODS." Thesis, Orléans, 2018. http://www.theses.fr/2018ORLE2056/document.
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Cette thèse est dédiée à l’étude des interactions entre les défauts lacunaires et les solutés (Y, Ti, O) pour mieux comprendre la formation des nanoparticules d’oxyde dans les aciers ODS (Oxide Dispersion Strengthened). Ces aciers sont envisagés comme matériau de structure dans la prochaine génération de réacteurs nucléaires fission et fusion. Leurs bonnes propriétés reposent essentiellement sur une répartition homogène de nanoparticules (YxTiyOz) de très faible taille. Cependant, l’obtention de cette répartition n’est pas encore maitrisée et le mécanisme de formation de ces nanoparticules n’est pas encore bien défini. Des modèles théoriques montrent que la présence de lacunes pendant l’étape de broyage pourrait impacter la formation de ces nanoparticules. Cette étude fait suite à la thèse de C. He et apporte de nouveaux résultats et de nouvelles interprétations et conclusions. Des implantations avec des ions Y, Ti, O ont été réalisées afin de simuler l’étape de broyage de ces aciers ODS. Elles ont permis d’introduire des défauts et les solutés désirés dans la matrice de fer α. Nous avons ensuite étudié les interactions entre les solutés et les défauts générés dans la matrice. La nature des défauts induits a été étudiée en fonction de l’ion implanté et de traitements thermiques après implantation par spectroscopie d’annihilation de positons (PAS) et corrélée avec les profils en profondeur des solutés obtenus par spectrométrie de masse des ions secondaires (SIMS). Les caractéristiques d’annihilation de certains défauts encore inconnues ont pu être déterminées. Les mesures SIMS ont montré que le titane ne migre pas entre 100 et 450°C et que l’oxygène présente un comportement complexe de migration et de piégeage dépendant de la température et de la microstructure des matériaux. Les résultats PAS montrent que les implantations ioniques conduisent à la formation de clusters lacunaires, de complexes lacunes-solutés et de dislocations dont la proportion change en fonction de la profondeur et de la nature de l’ion implanté. Les clusters de lacunes Vn et les dislocations sont détectés au-delà du pic d’implantation avec une fraction plus importante pour les dislocations indiquant que les défauts ont pu migrer pendant l’implantation. La proportion des complexes lacunes-solutés est maximale dans la zone d’arrêt des ions. Elle est en accord avec les énergies de liaison théoriques des complexes lacunes-soluté. La nature et la distribution des défauts formés évoluent en fonction de la température de recuit. Les clusters lacunaires Vn disparaissent entre RT et 300°C alors que les dislocations sont éliminées à partir de 400°C. Des phases oxydes sont détectées pour des recuits à 500 et 550°C en lien avec la contamination en oxygène. Des défauts dont la nature est non identifiée ont été mis en évidence pour des recuits réalisés entre 300 et 400°C dans les implantations O, Y et Y+O<br>This PhD thesis is dedicated to the study of interaction between vacancies and Y, Ti,O solutes for a better understanding of formation of oxide nanoparticles in ODS steel (Oxide Dispersion Strengthened). These ODS steels are considered as structural material for the next generation of fission and fusion nuclear reactors. Their good properties are induced by the fine dispersion of low size oxide nanoparticles. However, obtaining this distribution is not mastered and atomic scale clustering is not yet defined. Furthermore, it was shown by theoretical models that the presence of vacancy during mechanical alloying could affect the formation of these nanoparticles. This study follows upon on a previous study made by C.He, and bring new results, new interpretation and conclusions. Some implantations with Y, Ti, O ions with several energy have been made in order to simulate the mechanical alloying step used for ODS steel fabrication. Theses irradiations have induced defects and solutes into the iron matrix. Then we characterized samples using positron annihilation spectroscopy (PAS) and secondary ion mass spectrometry (SIMS). The nature of defects was studied according to nature of the implanted ion and the annealing temperature by PAS and correlated to depth profiles of solutes obtained by SIMS. Annihilation characteristics of some defects still unknown were able to be determined thanks to positron lifetime measurements. SIMS analysis showed that titanium doesn’t migrate for annealing experiments between 100°C and 450°C and that oxygen show a complex behavior of migration and trapping dependent on the microstructure of the material. PAS results show that ionic implantations produce vacancy clusters, dislocations and solutes-vacancies complex. Their proportion changes as a function of depth and nature of these irradiations. Vacancy clusters and dislocations are detected deeper than the implantation peak with a higher fraction for the dislocations indicating that the defects were able to migrate during implantations. The fraction of vacancy-solutes complexes is the highest in the ion stopping zone and is in a good agreement with the theoretical binding energy of vacancies-solutes complex. The nature and the distribution of the defects evolve according to the annealing temperature. Vacancy clusters disappear between RT and 300°C while the dislocations are eliminated from 400°C. Oxide phases are detected for annealing at 500 and 550°C in relation with the oxygen contamination during these annealings. Some defects which the nature is not yet identified were highlighted for annealing between 300 and 400°C for Y, O and Y+O irradiations
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Huang, Wei-Jhih, and 黃偉智. "Defect formation on graphene by carbon ion implantation." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/jwn6jz.
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碩士<br>國立中央大學<br>物理學系<br>106<br>In recent years, a variety of carbon-related materials, such as carbon nanotubes, fullerene…, etc, has been discovered and the properties has been investigated. One of them, well-known graphene, attracts the interest in scientists and lift a burst of whirlwind due to the fantastic characteristics. It has been adopted for semiconductor device and has a wide range of applications including single molecule gas sensor, field effects transistors (FETs), solar cell, light-emitting diodes (LED), touch panels and so on. Nevertheless, defect formation on various materials is inevitable during fabrication process, which can dramatically influence the electronic, mechanical, thermal or chemical property. Hence, understanding the mechanism of defect formation and stably controlling defect is an enduring substantial issue. According to the intrinsic properties, graphene is not equipped with band gap. By production of defect, band gap of graphene can be opened and then become n-type or p-type semiconductor by binding with different dopants. Despite of many researches on graphene for decades, the mechanism of defect formation and the technique of controlling defect is still not quite complete. In this literature, we will artificially produce defect on supported graphene by implanting carbon ions at different doping concentration, and discuss the intrinsic, as-implanted and post-annealing properties on silicon dioxide (SiO2) and gallium nitride (n-GaN) substrates. Comparing with different substrates, we can investigate the influence of supporting atoms and the rough surface on graphene. Furthermore, intrinsic properties of each sample is different from one to another, based on method to fabricating and transferring and amount of grain boundary, corrugations, absorption of gas and so on. Thus, we demonstrate the reproduction ability of graphene characteristics under the same processing and conditions. Corresponding to substantially important topic of stably controlling the properties of graphene in semiconductor devices, this is an advantageous research in industry.
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Schmidt, Matthias. "Space Charge Spectroscopy applied to Defect Studies in Ion-Implanted Zinc Oxide Thin Films." Doctoral thesis, 2011. https://ul.qucosa.de/id/qucosa%3A11364.
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Die vorliegende Arbeit befasst sich mit der Erzeugung und Detektion von Defekten im Halbleiter Zinkoxyd (ZnO). Der Fokus liegt dabei auf der Verwendung raumladungszonenspektroskopischer Techniken zur Detektion und Charakterisierung elektronischer Defektzustände. Es werden theoretische Aspekte von Raumladungszonen an Halbleitergrenzflächen und den darin enthaltenen elektronischen Defektzuständen behandelt. Das elektrische Potential in der Raumladungszone genügt einer nichtlinearen, eindimensionalen Poissongleichung, für die bekannte, näherungsweise Lösungen vorgestellt werden. Für eine homogen dotierte Raumladungszone gelang es, die exakte Lösung des Potentialverlaufs
als Integral anzugeben und einen analytischen Ausdruck für die Kapazität
der Raumladungszone zu berechnen. Desweiteren werden transiente und oszillatorische Lösungen der Differentialgleichung zur Beschreibung der Zeitentwicklung der Besetzungswahrscheinlichkeit von Defektzuständen für verschiedene experimentelle Bedingungen betrachtet. Sämtliche raumladungszonenspektroskopischen Experimente können durch geeignete Lösungen dieser beiden Differentialgleichungen beschrieben werden. Für die Fälle, für die keine analytischen Lösungen bekannt sind, wurde ein numerisches Modell entwickelt. Die Experimente wurden an ZnO Dünnfilmproben durchgeführt, welche mittels gepulster Laserablation auf Korundsubstraten abgeschieden wurden. Zur Erzeugung von Defekten wurden entweder Ionen in die Proben implantiert, die Proben mit hochenergetischen Elektronen bzw. Protonen bestrahlt oder einer thermischen Behandlung unterzogen. Die Raumladungszonen wurden durch Schottkykontakte realisiert. Durch die raumladungszonenspektroskopischen Verfahren, Kapazitäts-Spannungs Messungen, Admittanzspektroskopie, Deep-Level Transient Spectroscopy (DLTS), Minority Carrier Transient Spectroscopy, optische DLTS, Photokapazitäts- und Photostrommessungen, sowie der optischen Kapazitäts-Spannungs Messung konnten Defektzustände in der gesamten ZnO Bandlücke nachgewiesen werden. Durch Vergleiche der gemessenen Defektkonzentrationen in einer unbehandelten Referenzprobe mit denen in behandelten Proben konnten Aussagen über die experimentellen Bedingungen, unter denen intrinsische Defekte entstehen bzw. ausheilen, gewonnen und mit Stickstoff- bzw. Nickel- in Zusammenhang stehende Defekte identifiziert werden. Für eine Vielzahl untersuchter Defektzustände konnten die thermische Aktivierungsenergie der Ladungsträgeremission, Querschnitte für den Einfang freier Ladungsträger sowie die spektralen Photoionisationsquerschnitte bestimmt werden. Aus diesen Eigenschaften sowie den experimentellen Bedingungen unter denen der Defekt bevorzugt gebildet wird, wurden Rückschlüsse auf die mikroskopische Struktur einiger Defekte gezogen.
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Klug, Jan N. "Technologie und pysikalische Eigenschaften strahlungsinduzierter Zentren in Silizium." Doctoral thesis, 2011. https://monarch.qucosa.de/id/qucosa%3A18599.
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Die Arbeit beschäftigt sich mit der Erzeugung und den Eigenschaften strahlungsinduzierter Defekte in Silizium. Zur Erzeugung der untersuchten Zentren werden Wasserstoff- und Helium-Ionenstrahlen im MeV-Bereich verwendet. Die Untersuchung erfolgt mittels Spreading-Resistance- und temperaturabhängiger Hall-Messungen.
Betrachtet wird zunächst die Erzeugung einer n-Dotierung durch Wasserstoff-Implantation in Abhängigkeit von Implantationsparametern, - bedingungen und dem Ausheilprozess.
Für Helium-bestrahltes Silizium werden die Auswirkungen der Bestrahlung auf Widerstand, Ladungsträgerkonzentration und Beweglichkeit untersucht.
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Chen, U. L., and 陳威良. "Implantation Defects and SOI Formation by Plasma Immersion Ion Implantation." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/81841301621982578115.
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Hsu, Wei-Cheng, and 徐偉成. "High Energy Ion implantation Induced Defects Relevant to ULSI Applications." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/02866863045939123874.
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Hung, M. C., and 洪敏正. "Study of High Energy Si+ ion implantation defects in Silicon substrate." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/53888907484685903458.
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碩士<br>國立臺灣海洋大學<br>材料工程研究所<br>97<br>Defects in self-ion irradiated silicon were studied by using a transmission electron microscopy. The implantation experiment was proceeded by using National Electrostatics Corporation 3 MV 9SDH-2 Tandem Accelerator in Institute of Physics Academia Sinica. Si (100) samples were first implanted with 1 MeV Si ions and fluences from 5×1014 to 1×1016 ions/cm2. The implanted samples were annealed from 400 to 1000oC for 30 minutes. After high energy implanting, the resulted microstructure shows a heavy damage layer buried in silicon substrate, and a retained single crystalline region near the surface. A heavy damage layer with crystalline structure was observed in the as-implanted sample with a fluence of 5×1014 ions/cm2. However, a continuous and amorphous buried layer was first formed with a fluence of 2×1015 ions/cm2. The buried amorphous layer was at 1.0 μm away from the surface and about 0.5 μm width. As the ion fluence of up to 5×1015 ions/cm2, the amorphous layer was about 0.7 μm width and was saturated, that is, the amorphous width doesn’t increase apparently with ion fluence. The as-implanted samples were annealed from 400 to 1000oC for 30 minutes. Consequentially, it was found that there were not distinct recrystallization after 400 oC annealing, that is, it still showed the amorphous structure. The amorphous layer transfers to defects aggregation region after 800 oC annealing. As annealing temperature of up to 1000 oC, it showed the dislocation loops distributed at end of range.
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Amolo, George Odhiambo. "Optical and electrical properties of ion beam modified materials." Thesis, 2008. http://hdl.handle.net/10539/5409.
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"A study of ion implantation damage and its effects in silicon." 1997. http://library.cuhk.edu.hk/record=b5889201.
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by Chan Kwok Wai.<br>Thesis (M.Phil.)--Chinese University of Hong Kong, 1997.<br>Includes bibliographical references (leaves 93-95).<br>ACKNOWLEDGEMENT --- p.i<br>ABSTRACT --- p.ii<br>LIST OF SYMBOLS --- p.iii<br>LIST OF FIGURES --- p.v<br>LIST OF TABLES --- p.vi<br>Chapter CHAPTER ONE --- INTRODUCTION --- p.1<br>Chapter CHAPTER TWO --- SURVEYS ON ION IMPLANTATION DAMAGE STUDY --- p.6<br>Chapter 2.1 --- Introduction --- p.6<br>Chapter 2.1.1 --- Basic Theory --- p.7<br>Chapter 2.1.2 --- Amorphization --- p.9<br>Chapter 2.1.3 --- Amorphous Layer Regrowth --- p.10<br>Chapter 2.1.4 --- Point Defect Sources --- p.11<br>Chapter 2.1.5 --- Types of Extended Defects --- p.11<br>Chapter 2.2 --- Nature of Point Defects --- p.15<br>Chapter 2.2.1 --- Important Parameters --- p.15<br>Chapter 2.2.2 --- Vacancy Centers in Semiconductor --- p.16<br>Chapter 2.2.3 --- Self-interstitial in Silicon --- p.17<br>Chapter 2.2.4 --- Distribution of Excess Point Defects --- p.18<br>Chapter 2.2.5 --- Energy Level of Defect Species --- p.19<br>Chapter CHAPTER THREE --- EXPERIMENTAL METHOD --- p.21<br>Chapter 3.1 --- Experimental --- p.21<br>Chapter 3.2 --- Spreading Resistance Profiling --- p.25<br>Chapter CHAPTER FOUR --- MODELING OF SPREADING RESISTANCE PROFILES OF ION-IMPLANTED DAMAGE IN SILICON --- p.29<br>Chapter 4.1 --- Introduction --- p.29<br>Chapter 4.2 --- Basic equation --- p.30<br>Chapter 4.3 --- Formation of Model --- p.34<br>Chapter CHAPTER FIVE --- RESULTS AND DISCUSSION --- p.37<br>Chapter 5.1 --- Results --- p.37<br>Chapter 5.2 --- Discussion --- p.55<br>Chapter CHAPTER SIX --- CONCLUSION AND SUGGESTIONS OF FURTHER WORK --- p.58<br>Chapter 6.1 --- Conclusion --- p.58<br>Chapter 6.2 --- Suggestions of further work --- p.59<br>APPENDIX A --- p.60<br>APPENDIX B<br>SPREADING RESISTIVITY PROFILES --- p.62<br>REFERENCE --- p.93