Дисертації з теми "Semiconductor module"
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1
Halindintwali, Sylvain. "A study of hydrogenated nanocrystalline silicon thin films deposited by hot-wire chemical vapour deposition (HWCVD)." Thesis, University of the Western Cape, 2005. http://etd.uwc.ac.za/index.php?module=etd&.
Повний текст джерелаАнотація:
In this thesis, intrinsic hydrogenated nanocrystalline silicon thin films for solar cells application have been deposited by means of the hot &ndashwire chemical vapour deposition (HWCVD) technique and have been characterised for their performance. It is noticed that
hydrogenated nanocrystalline silicon is similar in some aspects (mainly optical) to its counterpart amorphous silicon actually used as the intrinsic layer in the photovoltaic industry. Substantial differences between the two materials have been found however in their respective structural and electronic properties.
We show that hydrogenated nanocrystalline silicon retains good absorption coefficients known for amorphous silicon in the visible region. The order improvement and a reduced content of the bonded hydrogen in the films are linked to their good stability. We argue that provided a moderate hydrogen dilution ratio in the monosilane gas and efficient process pressure in the deposition chamber, intrinsic hydrogenated nanocrystalline silicon with photosensitivity better than 102 and most importantly resistant to the Staebler Wronski effect (SWE) can be produced.
This work explores the optical, structural and electronic properties of this promising material whose study &ndash
samples have been exclusively produced in the HWCVD reactors based in the Solar Cells laboratory of the Physics department at the University of the Western Cape.
2
Mayne, Anna Louise. "A study of ATLAS semiconductor tracker module distortions and event cleaning with tracking." Thesis, University of Sheffield, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.554383.
Повний текст джерелаАнотація:
The search for new physics with the ATLAS detector at the LHC requires a thorough understanding of Standard Model physics and the performance of the detector. A reliable prediction of the Standard Model backgrounds combined with precise measurements of collision events at a previously unreachable centre of mass energy {/s = 7 TeV) in ATLAS provides excellent opportunities for new physics discoveries.
3
Grummel, Brian. "HIGH TEMPERATURE PACKAGING FOR WIDE BANDGAP SEMICONDUCTOR DEVICES." Master's thesis, University of Central Florida, 2008. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/3200.
Повний текст джерелаАнотація:
Currently, wide bandgap semiconductor devices feature increased efficiency, higher current handling capabilities, and higher reverse blocking voltages than silicon devices while recent fabrication advances have them drawing near to the marketplace. However these new semiconductors are in need of new packaging that will allow for their application in several important uses including hybrid electrical vehicles, new and existing energy sources, and increased efficiency in multiple new and existing technologies. Also, current power module designs for silicon devices are rife with problems that must be enhanced to improve reliability. This thesis introduces new packaging that is thermally resilient and has reduced mechanical stress from temperature rise that also provides increased circuit lifetime and greater reliability for continued use to 300°C which is within operation ratings of these new semiconductors. The new module is also without problematic wirebonds that lead to a majority of traditional module failures which also introduce parasitic inductance and increase thermal resistance. Resultantly, the module also features a severely reduced form factor in mass and volume.M.S.E.E.
School of Electrical Engineering and Computer Science
Engineering and Computer Science
Electrical Engineering MSEE
4
Filsecker, Felipe. "Characterization and evaluation of a 6.5-kV silicon carbide bipolar diode module." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2017. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-217848.
Повний текст джерелаАнотація:
This work presents a 6.5-kV 1-kA SiC bipolar diode module for megawatt-range medium voltage converters. The study comprises a review of SiC devices and bipolar diodes, a description of the die and module technology, device characterization and modelling and benchmark of the device at converter level. The effects of current change rate, temperature variation, and different insulated-gate bipolar transistor (IGBT) modules for the switching cell, as well as parasitic oscillations are discussed. A comparison of the results with a commercial Si diode (6.5 kV and 1.2 kA) is included. The benchmark consists of an estimation of maximum converter output power, maximum switching frequency, losses and efficiency in a three level (3L) neutral point clamped (NPC) voltage-source converter (VSC) operating with SiC and Si diodes. The use of a model predictive control (MPC) algorithm to achieve higher efficiency levels is also discussed. The analysed diode module exhibits a very good performance regarding switching loss reduction, which allows an increase of at least 10 % in the output power of a 6-MVA converter. Alternatively, the switching frequency can be increased by 41 %.
5
Poller, Tilo. "Thermal and thermal-mechanical simulation for the prediction of fatigue processes in packages for power semiconductor devices." Doctoral thesis, Universitätsbibliothek Chemnitz, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-154320.
Повний текст джерелаАнотація:
The knowledge about the reliability of power electronics is necessary for the design of converters. Especially for offshore applications it is essential to know, which fatigue processes happen and how the lifetime can be estimated. Numerical simulation is an important tool for the development of power electronic systems. This thesis analyse the thermal and thermal-mechanical behaviour of packages for power semiconductor devices with the help of simulations. One topic is the evaluation of different thermal models. The main focus is on the description of the thermal cross-coupling between the devices and the influence to the lifetime estimation. The power module is a well established package for power semiconductor devices. It will be explained how the heating period of power cycles influences the failure mode of this package type. Additionally, it will evaluated how SiC devices and DAB substrates influence the power cycling capability. The press-pack is in focus for high power applications as the package short-circuits during an electrical failure without external auxiliary systems. However, the knowledge about the power cycling behaviour is currently limited. With the help of simulations this behaviour will be analysed and possible weak points will be also derived. In the end of the work it will be discussed, how the lifetime can be estimated with help of FEM simulationsFür die Entwicklung von Umrichtern ist die Kenntnis über die Zuverlässigkeit der Leistungselektronik ein wichtiges Kernthema. Insbesondere für Offshore-Anwendungen ist das Wissen über die stattfindenden Ermüdungsprozesse und die Abschätzung der zu erwartenden Lebensdauer der Bauteile essentiell. Hierfür hat sich die Simulation als ein wichtiges Werkzeug für die Entwicklung und Lebensdauerbewertung von leistungselektronischen Anlagen etabliert. In der folgenden Arbeit wird das thermische und das thermisch-mechanische Verhalten der Leistungselektronik mittels Simulationen untersucht. Hierzu wird ein Vergleich zwischen verschiedenen thermischen Modellen für Leistungsbauelemente durchgeführt. Schwerpunkt ist die Beschreibung der thermischen Kopplung zwischen den Chips und deren Einfluss auf die Lebensdauerabschätzung. Ein weiterer Schwerpunkt ist das Leistungsmodul, welches sich als ein Standardgehäuse etabliert hat. Dazu wird erklärt, wie die Variation der Einschaltzeit im aktiven Lastwechseltest den Fehlermodus dieses Gehäusetyps beeinflusst. Weiterhin wird untersucht, wie SiC als Leistungshalbleiter und DAB als Substrat die Zuverlässigkeit beein- flusst. Der Press-Pack ist für Hochleistungsapplikationen von hohem Interesse, da dieses Gehäuse im elektrischen Fehlerfall ohne äußere Unterstützung kurzschliesst. Jedoch ist das Wissen über diese Gehäusetechnologie unter aktiven Lastwechselbedingungen sehr limitiert. Mit Hilfe von Simulationen wird dieses Verhalten untersucht und mögliche Schwachpunkte abgeleitet. Am Ende der Arbeit werden Möglichkeiten untersucht, wie Mithilfe von FEM Simulationen die Lebensdauer von Leistungsmodulen evaluiert werden kann
6
Poller, Tilo. "Thermal and thermal-mechanical simulation for the prediction of fatigue processes in packages for power semiconductor devices." Doctoral thesis, Universitätsverlag der Technischen Universität Chemnitz, 2014. https://monarch.qucosa.de/id/qucosa%3A20135.
Повний текст джерелаАнотація:
The knowledge about the reliability of power electronics is necessary for the design of converters. Especially for offshore applications it is essential
to know, which fatigue processes happen and how the lifetime can be estimated. Numerical simulation is an important tool for the development
of power electronic systems. This thesis analyse the thermal and thermal-mechanical behaviour of packages for power semiconductor devices with the help of simulations. One topic is the evaluation of different thermal models.
The main focus is on the description of the thermal cross-coupling between the devices and the influence to the lifetime estimation. The power module is a well established package for power semiconductor devices. It will be explained how the heating period of power cycles influences the failure mode of this package type. Additionally, it will evaluated how SiC devices and DAB substrates influence the power cycling capability. The press-pack is in focus for high power applications as the package short-circuits during an electrical failure without external auxiliary systems. However, the knowledge about
the power cycling behaviour is currently limited. With the help of simulations this behaviour will be analysed and possible weak points will be also
derived.
In the end of the work it will be discussed, how the lifetime can be estimated with help of FEM simulations.Für die Entwicklung von Umrichtern ist die Kenntnis über die Zuverlässigkeit der Leistungselektronik ein wichtiges Kernthema. Insbesondere für Offshore-Anwendungen ist das Wissen über die stattfindenden Ermüdungsprozesse und die Abschätzung der zu erwartenden Lebensdauer der Bauteile essentiell. Hierfür hat sich die Simulation als ein wichtiges Werkzeug für die Entwicklung und Lebensdauerbewertung von leistungselektronischen Anlagen etabliert. In der folgenden Arbeit wird das thermische und das thermisch-mechanische Verhalten der Leistungselektronik mittels Simulationen untersucht. Hierzu wird ein Vergleich zwischen verschiedenen thermischen Modellen für Leistungsbauelemente durchgeführt. Schwerpunkt ist die Beschreibung der thermischen Kopplung zwischen den Chips und deren Einfluss auf die Lebensdauerabschätzung. Ein weiterer Schwerpunkt ist das Leistungsmodul, welches sich als ein Standardgehäuse etabliert hat. Dazu wird erklärt, wie die Variation der Einschaltzeit im aktiven Lastwechseltest den Fehlermodus dieses Gehäusetyps beeinflusst. Weiterhin wird untersucht, wie SiC als Leistungshalbleiter und DAB als Substrat die Zuverlässigkeit beein- flusst. Der Press-Pack ist für Hochleistungsapplikationen von hohem Interesse, da dieses Gehäuse im elektrischen Fehlerfall ohne äußere Unterstützung kurzschliesst. Jedoch ist das Wissen über diese Gehäusetechnologie unter aktiven Lastwechselbedingungen sehr limitiert. Mit Hilfe von Simulationen wird dieses Verhalten untersucht und mögliche Schwachpunkte abgeleitet. Am Ende der Arbeit werden Möglichkeiten untersucht, wie Mithilfe von FEM Simulationen die Lebensdauer von Leistungsmodulen evaluiert werden kann.
7
Janík, Daniel. "Provozní parametry LED světelných zdrojů." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2017. http://www.nusl.cz/ntk/nusl-316394.
Повний текст джерелаАнотація:
The aim of the thesis is to introduce the basic photometric quantities and operating parameters of LED light sources, according to which the light sources are evaluated and compared. The thesis examines effects of high temperature and elevated stress on LED retrofits and a design of measurement methods to measure these influences. According to the proposed methods, nine samples of light sources were measured and compared to each other on a basis of the measurements. Comparison was made from the point of view of the energy as well as the quality of the produced light. The results were also compared to the parameters specified by the producers.
8
Grummel, Brian. "Design and Characterization of High Temperature Packaging for Wide-Bandgap Semiconductor Devices." Doctoral diss., University of Central Florida, 2012. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/5231.
Повний текст джерелаАнотація:
Advances in wide-bandgap semiconductor devices have increased the allowable operating temperature of power electronic systems. High-temperature devices can benefit applications such as renewable energy, electric vehicles, and space-based power electronics that currently require bulky cooling systems for silicon power devices. Cooling systems can typically be reduced in size or removed by adopting wide-bandgap semiconductor devices, such as silicon carbide. However, to do this, semiconductor device packaging with high reliability at high temperatures is necessary. Transient liquid phase (TLP) die-attach has shown in literature to be a promising bonding technique for this packaging need. In this work TLP has been comprehensively investigated and characterized to assess its viability for high-temperature power electronics applications. The reliability and durability of TLP die-attach was extensively investigated utilizing electrical resistivity measurement as an indicator of material diffusion in gold-indium TLP samples. Criteria of ensuring diffusive stability were also developed. Samples were fabricated by material deposition on glass substrates with variant Au–In compositions but identical barrier layers. They were stressed with thermal cycling to simulate their operating conditions then characterized and compared. Excess indium content in the die-attach was shown to have poor reliability due to material diffusion through barrier layers while samples containing suitable indium content proved reliable throughout the thermal cycling process. This was confirmed by electrical resistivity measurement, EDS, FIB, and SEM characterization. Thermal and mechanical characterization of TLP die-attached samples was also performed to gain a newfound understanding of the relationship between TLP design parameters and die-attach properties. Samples with a SiC diode chip TLP bonded to a copper metalized silicon nitride substrate were made using several different values of fabrication parameters such as gold and indium thickness, Au–In ratio, and bonding pressure. The TLP bonds were then characterized for die-attach voiding, shear strength, and thermal impedance. It was found that TLP die-attach offers high average shear force strength of 22.0 kgf and a low average thermal impedance of 0.35 K/W from the device junction to the substrate. The influence of various fabrication parameters on the bond characteristics were also compared, providing information necessary for implementing TLP die-attach into power electronic modules for high-temperature applications. The outcome of the investigation on TLP bonding techniques was incorporated into a new power module design utilizing TLP bonding. A full half-bridge inverter power module for low-power space applications has been designed and analyzed with extensive finite element thermo-mechanical modeling. In summary, TLP die-attach has investigated to confirm its reliability and to understand how to design effective TLP bonds, this information has been used to design a new high-temperature power electronic module.Ph.D.
Doctorate
Electrical Engineering and Computer Science
Engineering and Computer Science
Electrical Engineering
9
Dchar, Ilyas. "Conception d’un module d’électronique de puissance «Fail-to-short» pour application haute tension." Thesis, Lyon, 2017. http://www.theses.fr/2017LYSEI042/document.
Повний текст джерелаАнотація:
Les convertisseurs de forte puissance sont des éléments critiques des futurs réseaux HVDC. À ce titre, leur fiabilité et leur endurance sont primordiales. La défaillance d’un composant se produit soit en circuit ouvert, ou en court-circuit. Le composant défaillant en circuit ouvert est inadmissible pour les convertisseurs utilisant une topologie de mise en série. En particulier, dans certaines applications HVDC, les modules doivent être conçus de telle sorte que lorsqu'une défaillance se produit, le module défaillant doit se comporter comme un court-circuit et supporter ainsi le courant nominal qui le traverse. Un tel comportement est appelé “défaillance en court-circuit” ou “failure-to-short-circuit”. Actuellement, tous les modules de puissance ayant un mode de défaillance en court-circuit disponibles dans le commerce utilisent des semi-conducteurs en silicium. Les potentialités des semi-conducteurs en carbure de silicium (SiC) poussent, aujourd’hui, les industriels et les chercheurs à mener des investigations pour développer des modules Fail-to-short à base des puces SiC. C’est dans ce contexte que se situe ce travail de thèse, visant à concevoir un module à base de puces SiC offrant un mode de défaillance de court-circuit. Pour cela nous présentons d’abord une étude de l’énergie de défaillance des puces SiC, afin de définir les plages d’activation du mécanisme Fail-to-short. Ensuite, nous démontrons la nécessité de remplacer les interconnexions classiques (fils de bonding) par des contacts massifs sur la puce. Enfin, une mise en œuvre est présentée au travers d’un module “demi pont” à deux transistors MOSFETThe reliability and endurance of high power converters are paramount for future HVDC networks. Generally, module’s failure behavior can be classified as open-circuit failure and short-circuit failure. A module which fails to an open circuit is considered as fatal for applications requiring series connection. Especially, in some HVDC application, modules must be designed such that when a failure occurs, the failed module still able to carry the load current by the formation of a stable short circuit. Such operation is referred to as short circuit failure mode operation. Currently, all commercially available power modules which offer a short circuit failure mode use silicon semiconductors. The benefits of SiC semiconductors prompts today the manufacturers and researchers to carry out investigations to develop power modules with Fail-to-short-circuit capability based on SiC dies. This represents a real challenge to replace silicon power module for high voltage applications in the future. The work presented in this thesis aims to design a SiC power module with failure to short-circuit failure mode capability. The first challenge of the research work is to define the energy leading to the failure of the SiC dies in order to define the activation range of the Fail-to-short mechanism. Then, we demonstrate the need of replacing the conventional interconnections (wire bonds) by massive contacts. Finally, an implementation is presented through a "half bridge" module with two MOSFETs
10
Guiheneuf, Vincent. "Approche multi-physique du vieillissement des matériaux pour application photovoltaïque." Thesis, Paris Est, 2017. http://www.theses.fr/2017PESC1091/document.
Повний текст джерелаАнотація:
Cette thèse explore le vieillissement des modules photovoltaïques (PV) à base de silicium cristallin via une approche multi-matériaux. L’objectif premier est de déterminer les mécanismes de dégradation mis en jeu durant l’exploitation des modules PV et ainsi d’être à même de proposer des solutions technologiques améliorant leur durabilité. Pour cela, des tests de vieillissement accéléré ont été réalisés sur le verre, la cellule PV au silicium cristallin et le mini-module PV composé du verre, d’un polymère encapsulant et de la cellule silicium.Leurs propriétés fonctionnelles sont systématiquement évaluées et le suivi dans le temps de ces indicateurs permet de définir des lois de vieillissement. En parallèle, des caractérisations physico-chimiques sont réalisées pour définir les mécanismes de dégradations des différents constituants du module. L‘étude de la chaleur humide sur le verre a permis de mettre en évidence une dégradation de surface via un processus d’hydratation du réseau vitreux et un phénomène de lixiviation du sodium qui engendre une augmentation de la transmittance du verre. La cellule PV présente des performances électriques et une réflectance dégradées suite à l’exposition aux radiations UV dues à un processus de photo-oxydation de la couche antireflet SiNx. Il a également été établit qu’une puissance UV élevée peut aussi favoriser un phénomène de régénération des performances électriques. Le vieillissement du mini-module sous UV a montré du phénomène de dégradation photo-induite (LID) engendrant une légère diminution des performances électriques dès la première exposition alors que l’impact de la chaleur humide sur les performances électriques est nul après 2000 heures d’expositionThis thesis investigates the aging of photovoltaic (PV) modules based on crystalline silicon technology via a multi-material approach. The first objective is to determine the degradation mechanisms involved during the operation of the PV modules and thus to be able to propose technological solutions improving their durability. For this purpose, accelerated aging tests were carried out on the glass, the crystalline silicon PV cell and the PV mini-module composed of glass, a polymeric encapsulant and the silicon cell.Their functional properties are systematically evaluated and the follow-up of these indicators allows to define aging laws. In parallel, physicochemical characterizations are carried out to determine the degradation mechanisms of the different components of the module. The study of damp heat on glass throws into evidence a surface degradation with a hydration process of the silica network and a leaching phenomenon of the sodium which involves an increase of the glass transmittance. The PV cell exhibits a deterioration of the electrical performance and reflectance after UV radiation exposure due to a photo-oxidation process of the SiNx antireflection layer. It has also been established that high UV power can also promote a regeneration phenomenon of electrical performances. The aging of the mini-module under UV shows the phenomenon of photo-induced degradation (LID) generating a slight decrease in the electrical performance from the first exposure whereas the impact of damp heat on the electrical performance is null after 2000 hours
11
Muchindu, Munkombwe. "Electrochemical ochratoxin a immunosensors based on polyaniline nanocomposites templated with amine- and sulphate-functionalised polystyrene latex beads." Thesis, University of the Western Cape, 2010. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_3815_1306752491.
Повний текст джерелаАнотація:
Polyaniline nanocomposites doped with poly(vinylsulphonate) (PV-SO3 &minus
) and nanostructured polystyrene (PSNP) latex beads functionalized with amine (PSNP-NH2) and sulphate (PSNP-OSO3 &minus
) were prepared and characterised for use as nitrite electro-catalytic chemosensors and ochratoxin A immunosensors. The resultant polyaniline electrocatalytic chemosensors (PANI, PANI|PSNP-NH2 or PANI|PSNP-OSO3 &minus
) were characterized by cyclic voltammetry (CV), ultraviolet-visible (UV-Vis) spectroscopy and scanning electron microscopy (SEM). Brown-Anson analysis of the multi-scan rate CV responses of the various PANI films gave surface concentrations in the order of 10&minus
8 mol/cm. UV-vis spectra of the PANI films dissolved in dimethyl sulphoxide showed typical strong absorbance maxima at 480 and 740 nm associated with benzenoid p-p* transition and quinoid excitons of polyaniline, respectively. The SEM images of the PANI nanocomposite films showed cauliflower-like structures that were <
100 nm in diameter. When applied as electrochemical nitrite sensors, sensitivity values of 60, 40 and 30 &mu
A/mM with corresponding limits of detection of 7.4, 9.2 and 38.2 &mu
M NO2 &minus
, were obtained for electrodes, PANI|PSNP-NH2, PANI and PANI|PSNP-SO3 &minus
, respectively. Immobilisation of ochratoxin A antibody onto PANI|PSNP-NH2, PANI and PANI|PSNPSO3 - resulted in the fabrication of immunosensors.
12
Gálvez, Sánchez José-Luis. "Analysis of bidirectional switch power modules for matrix converter application." Doctoral thesis, Universitat Autònoma de Barcelona, 2017. http://hdl.handle.net/10803/457719.
Повний текст джерелаАнотація:
Existeix una creixent demanda en aplicacions industrials que requereixen una transferència bidireccional de potència entre la xarxa elèctrica i una càrrega i viceversa com per exemple: elevadors, escales mecàniques, energies renovables (molins de vent, fotovoltaica, cel·les de combustible, xarxes elèctriques intel·ligents), tracció elèctrica, etc. La possibilitat de dur a terme una conversió AC-AC directa sense un bus de contínua és una realitat gràcies a la topologia de convertidor matricial de potència (CM). La típica configuració d’un CM consisteix en nou interruptors bidireccionals (IBDs) que connecten directament tres fases d’entrada de la xarxa amb tres fases de sortida d’una càrrega (típicament un motor). Controlant els IBDs d’una manera adequada, es poden obtenir una amplitud i freqüència de sortida variables. Per tant, l’IBD controlable esdevé l’element clau en la implementació de CMs, el qual és capaç de conduir corrent i bloquejar tensió en ambdues polaritats (operació en quatre quadrants) i operar a elevades freqüències de commutació.
L’objectiu d’aquesta tesi és l’anàlisi dels processos de commutació en els IBDs, predir la seva potència dissipada en un CM en operació normal i el desenvolupament d’un nou mòdul interruptor bidireccional controlable que integra l’etapa de potència amb la de control en un component que millora la modularitat i la viabilitat de les aplicacions del CM.
Primer de tot és important entendre com es comporten els IBDs en un CM. Mitjançant la simulació SPICE d’un CM simplificat de dues fases d’entrada i una de sortida s’han pogut analitzar els fenòmens de commutació que es donen entre IBDs. Commutacions dures i febles són generades en els dispositius de potència depenent de la tensió i el signe del corrent en l’IBD. Entendre els detalls dels processos de commutació permet una definició òptima de les estratègies de commutació entre IBDs i modelar la potència dissipada deguda a la seva commutació.
S’han analitzat també les característiques estàtiques i dinàmiques de varis dispositius de potència de diferent tecnologies emprats per implementar IBDs. Per aquest propòsit s’ha fabricat un circuit de test dinàmic basat en el circuit simulat de dues fases d’entrada i una de sortida abans esmentat. Aquest circuit de test ha permès avaluar IBDs discrets i mòduls de potència IBD integrats amb la mateixa placa de potència i de control. La potència en conducció i commutació s’han pogut modelar d’una manera acurada gràcies a les mesures extretes del comportament dels dispositius de l’IBD.
Aquesta tesi descriu també la implementació d’un mètode de computació per avaluar la potència dissipada en conducció i commutació (dura i feble) dels dispositius de potència de l’IBD. En base als models de pèrdues en conducció i commutació, la potència dissipada dels dispositius ha estat calculada en funció de diferent condicions d’operació del CM com l’algoritme de modulació, la freqüència de sortida, el ràtio entre tensió de sortida i d’entrada, el factor de potència de la càrrega i la freqüència de commutació. Tot aquest estudi esdevé una eina pràctica per ajudar al dissenyador del convertidor alhora de seleccionar els dispositius de potència òptims donada una aplicació i de predir d’una manera precisa la potència dissipada dels dispositius de potència per dimensionar i implementar un correcte sistema d’extracció de calor.
Finalment, un prototipus de mòdul interruptor bidireccional integrat de potència i intel·ligent (IBD-IPM) s’ha dissenyat, fabricat i testejat en un CM de tres fases d’entrada i una de sortida per donar un pas endavant en l'aplicació pràctica dels CMs. El IBD-IPM és en si mateix un sistema de potència complex perquè moltes disciplines convergeixen en ell: dispositius semiconductors de potència, gestió tèrmica, control a nivell de dispositiu i control d’alt nivell.There is a wide and increasing demand in industrial applications which require bidirectional transfer of power between the AC utility and the load, and vice versa such as: rolling mills, elevators, centrifuges, escalators, renewable energies (wind turbines, photo-voltaic, fuel-cells; smart-grids), electric traction, etc. The possibility of performing a direct AC-AC conversion with the absence of a DC link is a fact thanks to the Matrix Converter (MC) topology. The typical configuration of a MC is based on nine bidirectional switches (BDSs) required to directly connect the three input phases of an AC grid with the three output phases of a load (typically, a motor). Controlling the BDSs in a suitable way, a variable amplitude and frequency can be obtained at the output. Consequently, the key element of the MC implementation is the controlled BDS which must be able to conduct current and block voltage in both polarities (four quadrant I-V operation) and to operate at relatively high switching frequencies. The aim of this thesis is the analysis of the commutation processes in BDSs, the prediction of their power dissipation in typical MC operation and the development of a new controlled bidirectional switch module which integrates the power stage functionality with the intelligence in one component to enhance the modularity and feasibility of MC applications First of all it is important to understand how behave the BDSs within a MC. A SPICE simulation work of a simplified two-phase to single-phase MC was performed in order to analyse the commutation phenomena involved between BDSs. Hard and soft commutations are undergone by the different power devices depending on the voltage across the BDS and the direction of the current through it. Understanding the details of the switching processes allow an optimum definition of the commutation strategies within BDSs and modelling of the switching power losses. The static and dynamic characteristics of several power devices of different technologies used in BDS implementations are also analysed. A switching test circuit based on the aforementioned two-phase to single-phase MC was fabricated for this purpose. This MC test circuit allowed testing discrete BDSs as well as integrated power modules sharing the same power stage and control board. Based on the extracted measured data of the BDSs devices, their conduction and their switching losses were accurately modelled. This thesis describes also the implementation of a computational method to evaluate the conduction and switching losses (hard and soft types) of the power devices within the BDS. Based on the conduction and switching losses models, the power losses of the semiconductor devices are calculated depending on different operating condition of the MC such as the modulation algorithm, the output frequency, the output to input voltage ratio, the load power factor and the switching frequency. All these studies resulted in a practical tool to help the converter designer to select the optimum power devices for a given application and to predict in an accurate way the semiconductors power losses in order to size and implement the suitable cooling system. Finally in this work, an integrated bidirectional switch intelligent power module (BDS-IPM) prototype is designed, built and tested in a three-phase to one-phase MC in order to take a step forward in the practical implementation of MCs. The BDS-IPM is itself a complex power electronics system since many disciplines converge in it: power semiconductor devices, thermal power management, device level control (i.e. gate drive circuits) and high level control (i.e. current commutation strategy implementation, active protection issues).
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Yoon, Kwang Sub. "A precision analog small-signal model for submicron MOSFET devices." Diss., Georgia Institute of Technology, 1990. http://hdl.handle.net/1853/14935.
Повний текст джерела
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Shelley, Valerie Anderson 1957. "Validity of the Jain and Balk analytic model for two-dimensional effects in short channel MOSFETS." Thesis, The University of Arizona, 1988. http://hdl.handle.net/10150/276801.
Повний текст джерелаАнотація:
The Jain and Balk analytic model for two-dimensional effects in short channel MOSFETS is investigated. The effects considered are Drain Induced Barrier Lowering, DIBL, and the maximum electric field, Emax, which influences Drain Induced High Field, DIHF. A scaled short channel design is used as the basis for the investigation. Cases are numerically simulated using the MINIMOS program. DIBL and Emax are calculated using the Jain and Balk model. Model values are compared to numerical simulation values. Results show the model consistently overestimates DIBL. Also, the range for which the model closely estimates Emax is found. Variation in Emax with change of junction depth Xj is investigated. The electric field, Ex, as it varies with depth in the channel is investigated, and compared to the Jain and Balk approximation. The deviations suggest that the model must break down for short channels.
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Furfaro, Luca. "Dynamique modale des lasers à semiconducteur." Nice, 2003. http://www.theses.fr/2003NICE4094.
Повний текст джерелаАнотація:
La dynamique modale des lasers à semiconducteur est le sujet de cette thèse. En particulier, nous présentons un nouveau type de dynamique caractérisée par des oscillations périodiques de l’intensité modale et par une intensité totale d’émission constante. Nous avons effectué une série de mesures systématiques sur une large gamme de lasers à puits quantiques (PQ) et nous avons vérifié que ces oscillations périodiques de l’intensité modale sont une caractéristique générale de ce type de lasers. Nous avons déterminé pour quelle région de paramètres cette dynamique peut être observée et comment cette dernière change en modifiant les paramètres de contrôle externes (température et courant de pompage). Ce nouveau type de comportement dynamique est extrêmement robuste et insensible au bruit électrique et optique. Une large étude a été effectuée sur les conséquences de la rétroaction optique : des effets drastiques on été observés en fonction de l’intensité et de la phase de la rétroaction. Nous avons comparé la statistique des lasers à semiconducteur à PQ avec celle des lasers massifs en mettant en évidence la différente nature physiques des dynamiques observées dans ces deux types de lasers. A l’aide d’un modèle théorique qui explique les observations expérimentales dans le laser à semiconducteur à PQ, nous montrons que le mécanisme dominant pour l’apparition de la dynamique est le mélange à quatre ondes. L’ordre d’allumage est expliqué grâce à l’asymétrie de la réponse optique du milieu semiconducteurLa dinamica modale dei laser a semiconduttore è l’argomento di questa tesi. In particolare, presentiamo un nuovo tipo di comportamento dinamico caratterizzato da oscillazioni periodiche dell’intensit`a modale, con un’intensità totale d’emissione costante. Abbiamo effettuato una serie di misure sistematiche su una larga gamma di laser a “buca quantica” (quantum well, QW) ed abbiamo verificato che queste oscillazioni periodiche dell’intensità modale sono una caratteristica generale per questo tipo di dispositivo. Abbiamo definito in quali regioni dei parametri si osservi questa dinamica e come quest’ultima si modifichi cambiando i parametri di controllo esterni (temperatura e corrente di pompa). Questo nuovo tipo di dinamica è estremamente stabile ed insensibile al rumore elettrico ed ottico. Uno studio dettagliato è stato effettuato sugli effetti della retroazione ottica: la dinamica pu`o essere modificata in modo drastico in funzione della fase e del”intensit`a della retroazione. Abbiamo confrontato la statistica dei laser a semiconduttore a QW con quella dei laser “bulk” sottolineando la diversa natura fisica della dinamica osservata nei due tipi di laser. Con l’aiuto d’un modello teorico che spiega le osservazioni sperimentali nei laser a semiconduttore a QW, si constata che l’interazione a quattro onde è l’elemento dominante per la comparsa di tale comportamento dinamico. L’ordine dell’accensione dei modi è spiegato grazie all’asimmetria della risposta ottica nei materiali a semiconduttore
The modal dynamics of semiconductor lasers is the subject of this thesis. We present a new kind of dynamics characterized by periodic oscillations of the modal intensity and constant total intensity. We perform systematic measurements on several QW lasers and verify that the periodic oscillations of the modal intensity are a general characteristic for this kind of device. We study the parameter range where we can observe this dynamics and how its temporal and spectral features are affected by changes in the control parameters (temperature and pumping current). This new kind of dynamics is very robust and insensitive to electrical and optical noise. We perform a ample study on the effects of optical feedback: substantial changes can be observed as a function of the intensity and phase of the feedback. We compare the statistics of bulk and QW semiconductor lasers and show the different physical nature of the observed dynamics for these two kinds of lasers. With the help of a new theoretical model, which explains the experimental observations in QW lasers, we show that four-wave-mixing is the dominant mechanism for the appearance of the observed dynamics. The sequence of mode switching is explained from the spectral asymmetry of the optical response in semiconductor media
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Kesserwani, Joseph. "Développement et implantation d’un modèle de diode par VHDL-AMS : Discrétisation selon la méthode Scharfetter-Gummel." Thesis, Lyon, INSA, 2015. http://www.theses.fr/2015ISAL0073/document.
Повний текст джерелаАнотація:
La conception assistée par ordinateur (CAO) est largement utilisée dans l’industrie des semi-conducteurs pour la conception et l’analyse des différents composants dont l’étude consiste à résoudre l'équation de dérive-diffusion et l’équation de Poisson. La caractéristique non linéaire de ces équations demande des solutions numériques interactives. Le schéma de Scharfetter-Gummel est utilisé classiquement pour discrétiser l'équation de dérive-diffusion non dégénérée (ou équation de Schockley) pour simuler les phénomènes de transport des particules «électrons et trous» dans un semi-conducteur. Initialement cette méthode a été appliquée à un domaine unidimensionnel. Par la suite, cette méthode a été étendue au problème bidimensionnel sur la base d'un maillage rectangulaire. L’objectif donc de cette thèse serait d’implanter un modèle de diode par VHDL-AMS basé sur la discrétisation selon la méthode Scharfetter-Gummel. Le langage VHDL-AMS (Hardware Description Language – Analog Mixed Signal) est un langage de description comportemental pour les circuits analogiques et mixtes. Inspiré de son équivalent pour les circuits logiques, le VHDL, VHDL-AMS serait donc une extension. Etant donné que le langage VHDL-AMS est de haut niveau, ceci nous permettra de modéliser le comportement de systèmes physiques, électriques, mécaniques ou autres. Parallèlement VHDL-AMS permet de créer des modules, appelés « entités ». Ceux-ci sont définis par leurs ports externes (qui sont une interface avec les autres architectures ou entités) et par des équations mathématiques. La possibilité d’utiliser directement des relations mathématiques lors de la description du modèle nous donne une grande souplesse d’utilisation. Comme tous les langages de description comportementale analogique, VHDL-AMS est initialement dédié à la modélisation de type « haut niveau », tel que la modélisation d’un système électronique complet. L’utilisation d’un tel langage afin de réaliser un modèle de diode, constitue donc une alternative de ce dernier. En raison du grand nombre de nœud il est nécessaire de générer le code VHDL-AMS à partir d'une interface de type java. Les résultats obtenus par cette méthode seront comparés avec d'autres obtenus par différents autres logiciels. Le modèle à concevoir aura comme objectif : - Correspondre aux spécifications initialement tracés par les concepteurs et ceci afin de leur permettre de mettre en évidence les différentes caractéristiques des modules. - Simuler facilement l'intégration et/ou l'adéquation du composant dans un système donné - être conçus de sorte qu'il soit utilisé dans des composants plus complexesComputer-aided design (CAD) is widely used in the semiconductor industry for the design and analysis of individual components whose study is to solve the drift-diffusion equation and the Poisson equation. The nonlinear characteristic of these equations request interactive digital solutions. The diagram Scharfetter-Gummel is conventionally used to discretize the non-degenerate drift-diffusion equation (or equation Schockley) to simulate particle transport phenomena "electrons and holes" in a semiconductor. Initially this method was applied to a one-dimensional domain. Subsequently, this method was extended to the two-dimensional problem on the basis of a rectangular mesh. So the aim of this thesis is to implement a VHDL-AMS diode model based on the discretization using the Scharfetter-Gummel method. The VHDL-AMS (Hardware Description Language - Analog Mixed Signal) is a behavioral description language for analog and mixed circuits. Inspired by its equivalent for logic circuits, VHDL, VHDL-AMS would be an extension. Since the VHDL-AMS is high level, this will allow us to model the behavior of physical systems, electrical, mechanical or otherwise. Meanwhile VHDL-AMS can create modules, called "entities". These are defined by their external ports (which are an interface with other architectures or entities) and by mathematical equations. The ability to use mathematical relationships directly in the description of the model gives us great flexibility. Like all analog behavioral description languages, VHDL-AMS is initially dedicated to the modeling of the type "high level" as the modeling of complete electronic systems. The use of such a language in order to achieve a diode model thus constitutes an alternative to the latter. Due to the large number of node it is necessary to generate the VHDL-AMS code from a Matlab-based interface. The results obtained by this method will be compared with others from various softwares. The model design will aim: - Match the specifications originally drawn by designers and in order to allow them to highlight the different characteristics of the modules. - Easily Simulate integration and / or the component adequacy in a given system - Be designed so that it is used in more complex components. -Finally We plan to conduct experimental measures in order to verify the accuracy of our model
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Rodriguez, Maria P. "Thermal characterisation and reliability study of advanced high power modules using finite element techniques." Thesis, Staffordshire University, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.364813.
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Malape, Maibi Aaron. "Low temperature growth of Amorphous Silicon thin film." Thesis, University of the Western Cape, 2007. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_7768_1254727160.
Повний текст джерелаАнотація:
The growth of amorphous hydrogenated silicon (a-Si:H) thin films deposided by hot wire chemical vapor deposition (HWCVD) has been studied. The films have been characterised for optical and structural properties by means of UV/VIS,FITR,ERDA, XRD.XTEM and Raman spectroscopy. Low subtrate heater temperatures in the range form 130 to 200 degrees celcius were used in this thesis because it is believed to allow for the deposition of device quality a-Si:H which can be used for electronic photovoltaic devices. Furthermore, low temperatures allows the deposition of a-Si:H on any subtrate and thus offers the possibility of making large area devices on flexible organic substances. We showed that the optical and structural properties of grown a-Si:H films depended critically upon whether the films were produced with silane gas or silane diluted with hydrogen gas. We also showed that it is possible to to deposit crystalline materials at low temperature under high hydrogen dilution ratio of silane gas.
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Simpson, James. "Theoretical studies of Jahn-Teller impurity ion complexes in III-V semiconductors." Thesis, University of Nottingham, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.329837.
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20
Salem, Ali F. "Advanced numerical simulation modeling for semiconductor devices and it application to metal-semiconductor-metal photodetectors." Diss., Georgia Institute of Technology, 1995. http://hdl.handle.net/1853/13834.
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21
Adams, Stephen E. "Semiconductor device modelling using the multigrid method." Thesis, University of British Columbia, 1988. http://hdl.handle.net/2429/27787.
Повний текст джерелаАнотація:
This thesis examines the application of the multigrid method to the semiconductor equations. An overview of semiconductor device modelling in presented, and the multi-grid method is described. Several modifications to the basic multigrid algorithm are evaluated based on their performance for a one dimensional model problem. It was found that using a symmetric Gauss-Seidel relaxation scheme, a special prolongation based on the discrete equations, and local relaxation sweeps near the pn-junctions produced
a robust, and efficient code. This modified algorithm is also successful for a wide variety of cases, and its performance compares favourably with other multigrid algorithms that have been applied to the semiconductor equations.Science, Faculty of
Mathematics, Department of
Graduate
22
Habib, Mohammad Humayun. "Semiconductor P-N Junction Space Charge Region Capacitance." PDXScholar, 1992. https://pdxscholar.library.pdx.edu/open_access_etds/4589.
Повний текст джерелаАнотація:
The classical capacitance voltage characteristics based on the depletion approximation, is adequate at reverse bias, but introduces errors at high forward bias. Because of its inherent simplicity and compactness this classical depletion model is well studied and widely used in circuit simulators. In this work, a new model for the semiconductor space charge region (SCR) capacitance, based on physical justification, will be derived. This new model takes three input parameters, C0 , Vbi and m, thus eliminating the fitting parameter FC currently used in SPICE. This new model is applicable for any applied voltage and will be compared with the SCR capacitance extracted from the numerical device simulator PISCES, and with the SCR capacitance models proposed by Gummel and Poon and by DeGraaff and Klaassen.
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Weil, Thierry. "Etude theorique du transport perpendiculaire aux couches dans les semiconducteurs 3-5 modules suivant une dimension." Paris 6, 1987. http://www.theses.fr/1987PA066099.
Повний текст джерелаАнотація:
Proposition d'un modele pour le transport inelastique et application au transport assiste par phonons entre deux puits quantiques, a la capture des porteurs par le puits quantique d'un laser sch, au transport dans les pseudoalliages quaternaires et dans les superreseaux. Analyse des differents modeles de l'effet tunnel et discussion de la duree de l'effet tunnel; application aux diodes a double barriere et mise en evidence de l'equivalence des descriptions basees sur l'effet tunnel resonnant et sur l'effet tunnel sequentiel, au moins en regime continu; effets des diffusions, developpement d'un modele sequentiel a partir du formalisme d'oppenheimer. Algorithme de calcul du transport perpendiculaire dans les heterostructures (approche de la cao des structures de bande)
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Smith, Arlynn W. "Light confinement and hydrodynamic modeling of semiconductor structures by volumetric methods." Diss., Georgia Institute of Technology, 1992. http://hdl.handle.net/1853/13407.
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Coles, Richard A. "Theory of the electronic states of semiconductor heterostructures." Thesis, Durham University, 1999. http://etheses.dur.ac.uk/4495/.
Повний текст джерелаАнотація:
This thesis is concerned with theoretical calculations of the properties of electronic bound states in semiconductor heterostructures. The complex band structure empirical pseudopotential method (EPM) is used as the foundation of the work. Spin orbit coupling and strain effects (due to lattice mismatch) are included in familiar ways, as is the transfer matrix method, allowing the study of arbitrarily configured heterostructures. These techniques are used to investigate the unusually deep InAs/AlSb conduction band well. The strong possibility of intraband transitions at electro magnetic wavelengths around 1.55µm is predicted, with corresponding enhanced momentum matrix elements and joint density of states over interband transitions. An InAs/GaSb/AlSb asymmetric well is investigated, paying particular attention to the bound states in the vicinity of the InAs/GaSb band overlap. The electron-like states are found to cross with heavy hole and anti-cross with light hole-like states, as a function of heterostructure dimension or applied electrostatic field. This is analogous to the hybridisation of states in the in-plane band structure, except that for zero in-plane wave vector there can be no appreciable hybridisation of electron and heavy hole states. A technique is described that has been developed to extract envelope functions from heterostructure wavefunctions calculated using the realistic complex band structure EPM approach. These envelope functions conform to Burt’s theory (M. G. Burt, J. Phys.: Condens. Matt. 4, 6651 (1992)) in that they are uniquely defined, continuous and smooth over all space. Comparisons with traditional effective mass envelope functions are made. The extracted envelope functions are used to demonstrate conclusively Burt's predictions (M. G. Burt, Superlatt. Mi- crostruct. 17, 335 (1995)) concerning the inadequacy of certain approximations for the calculation of interband dipole matrix elements and charge oscillation. Finally, the issue of k • p operator ordering is convincingly settled, in favour of 'ordered' over 'symmetrised' Hamiltonians, by comparison to EPM calculations, and using EPM derived k • p parameters.
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Kitchin, Matthew Roger. "Theory of semiconductor heterostructures for infrared applications." Thesis, University of Newcastle Upon Tyne, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.300192.
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Gay, Simon Christopher Anthony. "Theoretical studies of adsorbate covered semiconductor surfaces." Thesis, University of Exeter, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.302534.
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Racca, Stephen Douglas. "Improving operational efficiency of a semiconductor equipment manufacturing warehouse through effective utilization of Vertical Lift Modules." Thesis, Massachusetts Institute of Technology, 2015. http://hdl.handle.net/1721.1/101335.
Повний текст джерелаАнотація:
Thesis: M. Eng. in Manufacturing, Massachusetts Institute of Technology, Department of Mechanical Engineering, 2015.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 59-60).
This thesis deals with improving the operational efficiency of automated part storage devices, in this case Vertical Lift Modules (VLM). This was accomplished by using dynamic slotting to maximize and maintain high material throughput, eliminating the need for periodic reslotting. Multiple VLMs can be used in parallel picking operations to improve material throughput. Common industry practice is to periodically reslot items once an unbalanced workload is obvious. This thesis investigates a method to avoid periodic reslotting by using incoming parts as a means to maintain a balanced workload amongst VLMs. Three different part allocation strategies are compared, namely Randomization, Snake and Order Grouping to determine their effectiveness and respective feasibility. The three strategies are then crafted into logical systems that could be used to strategically place received parts and eliminate the need for periodic reslotting. The Snake method was found to be the most well suited for this particular situation due to the small order sizes. This method provides a 35% savings in pick time, which is equivalent to approximately 733 hours annually.
by Stephen Douglas Racca.
M. Eng. in Manufacturing
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Kim, Hyun-Woong. "CMOS RF transmitter front-end module for high-power mobile applications." Diss., Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/47592.
Повний текст джерелаАнотація:
With the explosive growth of the wireless market, the demand for low-cost and highly-integrated radio frequency (RF) transceiver has been increased. Keeping up with this trend, complimentary metal-oxide-semiconductor (CMOS) has been spotlighted by virtue of its superior characteristics. However, there are challenges in achieving this goal, especially designing the transmitter portion. The objective of this research is to demonstrate the feasibility of fully integrated CMOS transmitter module which includes power amplifier (PA) and transmit/receive (T/R) switch by compensating for the intrinsic drawbacks of CMOS technology.
As an effort to overcome the challenges, the high-power handling T/R switches are introduced as the first part of this dissertation. The proposed differential switch topology and feed-forward capacitor helps reducing the voltage stress over the switch devices, enabling a linear power transmission. With the high-power T/R switches, a new transmitter front-end topology - differential PA and T/R switch topology with the multi-section PA output matching network - is also proposed. The multi-stage PA output matching network assists to relieve the voltage stress over the switch device even more, by providing a low switch operating impedance. By analyzing the power performance and efficiency of entire transmitter module, design methodology for the high-power handling and efficient transmitter module is established. Finally, the research in this dissertation provides low-cost, high-power handling, and efficient CMOS RF transmitter module for wireless applications.
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Lee, Seungwon. "Laser excited and multiply charged semiconductor quantum dots modeled by empirical tight binding /." The Ohio State University, 2002. http://rave.ohiolink.edu/etdc/view?acc_num=osu1486462067842958.
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IVERSON, ARTHUR EVAN. "THE MATHEMATICAL MODELING OF TIME-DEPENDENT PHOTOCONDUCTIVE PHENOMENA IN SEMICONDUCTORS." Diss., The University of Arizona, 1987. http://hdl.handle.net/10150/184068.
Повний текст джерелаАнотація:
This dissertation presents results pertaining to the mathematical modeling of semiconductor photoconductors and includes the formulation, analysis, and solution of photoconductive device model equations. The fundamental semiconductor device equations of continuity and transport are derived for the case of a material which contains a large density of deep-level impurities. Electron and hole trapping on deep-level impurities is accounted for by trapping-kinetics rate equations. The coupling between carrier drift and the electric field is completed through Poisson's equation. Simple, nonlinear model equations are presented for bulk-material response based on the dynamics of electron and hole trapping and recombination on deep-level impurities. The characteristics of the solution to these model equations are observed to depend strongly on the excitation intensity. These model equations qualitatively reproduce observed experimental behavior of an iron-doped indium phosphide photoconductor. A theory of the effect of deep-level centers on the generation-recombination noise and responsivity of an intrinsic photoconductor is presented. It is shown that the deep-level centers can influence the generation-recombination noise and responsivity in three main ways: (i) they can shorten the bulk carrier lifetime by Schockley-Read-Hall recombination; (ii) for some values of the capture cross sections, deep-level densities, and temperature, the deep-level centers can trap a significant fraction of the photogenerated minority carriers. This trapping reduces the effective minority carrier mobility and diffusivity and thus reduces the effect of carrier sweep out on both generation noise and responsivity; (iii) the deep-level centers add a new thermal noise source, which results from fluctuations between bound and free carriers. The strength of this new noise source decreases with decreasing temperature at a slower rate than band-to-band thermal generation-recombination noise. Photoconductive device model equations based on time-dependent, convective/diffusive transport equations are presented. The system of model equations is solved numerically with boundary conditions that represent ideal ohmic contacts. Computed results are presented for different photoconductor lengths and bias voltages with spatially uniform, rectangular light-pulse illumination.
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He, Jianqing. "Finite difference time domain simulation of subpicosecond semiconductor optical devices." Diss., This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-05042006-164534/.
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Sendon, Perez Juan Alejandro. "Risk minimization through metrology in semiconductor manufacturing." Thesis, Lyon, 2017. http://www.theses.fr/2017LYSEM022.
Повний текст джерелаАнотація:
Cette thèse consiste à analyser les différentes propriétés des ateliers de métrologie, proposer de nouvelles approches pour optimiser les taux d'échantillonnage et développer de nouvelles stratégies dynamiques de réduction des risques en fabrication des semi-conducteurs.Une analyse approfondie des ateliers de métrologie sur le site de Rousset de STMicroelectronics a été réalisée. Leurs propriétés physiques ainsi que leurs caractéristiques, comme la qualification des mesures, les stratégies d'échantillonnage et d’ordonnancement des lots et les niveaux de risque, sont prises en compte. De plus, une nouvelle procédure a été développée pour aider à déterminer quelle stratégie d'échantillonnage convient le mieux aux caractéristiques de l’atelier de métrologie et aux valeurs de risque.De nouvelles approches sont ensuite proposées pour optimiser les taux d'échantillonnage des différents types de machines de métrologie en respectant la capacité de métrologie et en prenant en compte des paramètres tels que les débits des machines de production et de métrologie et les probabilités de défaillance des machines de production. Les résultats montrent que la capacité de métrologie est mieux utilisée et que les machines de production sont contrôlées de manière efficace, en fonction de leurs caractéristiques, avec une priorité plus forte sur les machines critiques.Dans la dernière partie de la thèse, des modèles de simulation de plusieurs ateliers de métrologie sont développés. Ces modèles reproduisent le comportement des ateliers pour mieux les comprendre et évaluer l'impact d’améliorations qui sont proposéesThis thesis consists in analyzing the different properties of metrology workshops, proposing novel approaches to optimize sampling rates and developing new dynamic strategies for risk reduction in semiconductor manufacturing.A thorough analysis of metrology workshops in the site of Rousset of STMicroelectronics has been carried out. Their physical properties and also their characteristics, such as measure qualification, lot sampling and dispatching strategy and risk levels, are considered. Also, a new procedure is developed that helps to determine which sampling strategy fits better according to the metrology workshop characteristics and risk values.New approaches are then proposed to optimize the sampling rates for different types of metrology tools respecting the metrology capacity and taking into account parameters such as throughput rates of process machines and metrology tools, and the failure probabilities of process machines. The numerical experiments show that the metrology capacity is better used and process machines are efficiently controlled, depending on their characteristics, paying more attention the critical machines.In the final part of the thesis, simulation models of several metrology workshops are developed. These models reproduce the behaviour of the workshops to better understand them and to evaluate the impact of proposed improvements
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Pradeep, Kumar Anjali. "Chemo-Thermo Cure of Viscoelastic Materials for Semiconductor Packaging Applications." PDXScholar, 2018. https://pdxscholar.library.pdx.edu/open_access_etds/4537.
Повний текст джерелаАнотація:
Viscoelastic polymer materials are being actively considered as a novel material for semiconductor packaging applications as a result of their ability to develop strong adhesive bonds at lower temperatures. Viscoelastic thermoset materials are impacted by the stresses generated during the curing process, which is also accompanied by a dissipation of thermal energy. There is a need to develop a generic modeling formulation that is applicable to any material of interest in order to enable the study of different bonding materials and develop optimized curing cycles. This study reports a numerical formulation to evaluate the stress generated and energy dissipated during the cure of viscoelastic polymers. A generalized method to define the transient variation of degree of cure was developed using a 4th order Runge Kutta approximation. The mathematical formulation was implemented using a novel evaluation methodology that helped reduce the computational power requirement. The commercially-available 3501-6 resin was simulated as a characteristic material in this study. The numerical model was validated against analytically derived solutions for both a single Maxwell model, and a Generalized Maxwell Model (GMM) for cases of constant-strain inputs, and subsequently for sinusoidal strain inputs, wherein, material properties were considered to be constant or varying linearly with degree of cure. A good agreement was obtained between the present model and analytical solutions.
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Chen, Quan, and 陈全. "Efficient high-frequency electromagnetic simulation in VLSI: rough surface effects and electromagnetic-semiconductor coupled simulation." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2010. http://hub.hku.hk/bib/B44904940.
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李華剛 and Eddie Herbert Li. "Narrow-channel effect in MOSFET." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1990. http://hub.hku.hk/bib/B31209312.
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Xu, Yuanzhe, and 徐远哲. "Variational analysis for 3D integrated circuit on-chip structures based on process-variation-aware electromagnetic-semiconductor coupledsimulation." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2011. http://hub.hku.hk/bib/B47047616.
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Liu, Wenxian. "Interpreting and forecasting the semiconductor industry cycle." free to MU campus, to others for purchase, 2002. http://wwwlib.umi.com/cr/mo/fullcit?p3060119.
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Bradley, Frank Mitchell. "Transport imaging for the study of quantum scattering phenomena in next generation Semiconductor devices /." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2005. http://library.nps.navy.mil/uhtbin/hyperion/05Dec%5FBradley.pdf.
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Pellecuer, Guillaume. "Fatigue thermomécanique des connexions dans les modules de puissance à semi-conducteurs." Thesis, Montpellier, 2019. http://www.theses.fr/2019MONTS038.
Повний текст джерелаАнотація:
Le sujet de thèse porte sur le vieillissement des modules de puissance à semi-conducteurs. En fonctionnement, ces modules subissent un échauffement propre qui peut varier cycliquement dans le temps quand l’application impose un régime électrique variable. On parle alors de cyclage thermique, mécanisme qui impose d’importantes contraintes thermomécaniques sur les connexions internes et peut conduire à leur endommagement. Cette problématique constitue le coeur du travail de thèse. Il s’appuie sur l’intégration de lois de comportement adaptées dans des outils logiciel de type "éléments finis" pour conduire l’étude d’un module représentatif de la technologie actuelle. D’un point de vue expérimental, la mise en oeuvre de tests sur des modules "classiques" est relativement complexe et l’exploitation des résultats par des techniques d’imageries demande un travail préalable important. Pour pallier ces inconvénients, le travail présenté ici propose une démarche de réalisation d’échantillons spécifiques se focalisant sur le vieillissement d’un fil de bonding. L’utilisation de ces nouveaux véhicules de tests permet de suivre plus aisément l’endommagement et facilite l’analyse post vieillissement. En complément, des études de vieillissement sur des modules génériques pour différentes valeurs de vitesses de cyclage permettent d’évaluer l’hypothèse de l’indépendance de la fatigue vis à vis de cette vitesse de cyclageThe thesis topic is the aging of semiconductor power modules. During operation, these modules undergo a specific heating which can vary cyclically over time when the application requires a variable electric mode. This is referred to as thermal cycling, a mechanism that imposes significant thermomechanical stresses developed by the internal connections and can lead to their damage. This problem constitutes the core of the thesis work. It will rely on the integration of adapted constitutive behavioural laws into "finite element" software tools to study a module representative of current technology. From an experimental standpoint, the implementation of tests on "classical" modules is relatively complex and the exploitation of the results by imaging techniques requires significant preliminary work. To overcome these drawbacks, the work presented here proposes a specific sample production approach focusing on the ageing of a bonding wire. The use of these new test vehicles makes the monitor damage easier as well as post-ageing analysis. In addition, ageing studies on generic modules for different cycling frequencies should help us to better understand the hypothesis of the independence of fatigue with respect to cycling speed
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Yoon, Sangwoong. "LC-tank CMOS Voltage-Controlled Oscillators using High Quality Inductor Embedded in Advanced Packaging Technologies." Diss., Georgia Institute of Technology, 2004. http://hdl.handle.net/1853/4887.
Повний текст джерелаАнотація:
This dissertation focuses on high-performance LC-tank CMOS VCO design at 2 GHz. The high-Q inductors are realized using wiring metal lines in advanced packages. Those inductors are used in the resonator of the VCO to achieve low phase noise, low power consumption, and a wide frequency tuning range.
In this dissertation, a fine-pitch ball-grid array (FBGA) package, a multichip module (MCM)-L package, and a wafer-level package (WLP) are incorporated to realize the high-Q inductor. The Q-factors of inductors embedded in packages are compared to those of inductors monolithically integrated on Si and GaAs substrates. All the inductors are modeled with a physical, simple, equivalent two-port model for the VCO design as well as for phase noise analysis. The losses in an LC-tank are analyzed from the phase noise perspective.
For the implementation of VCOs, the effects of the interconnection between the embedded inductor and the VCO circuit are investigated. The VCO using the on-chip inductors is designed as a reference. The performance of VCOs using the embedded inductor in a FBGA and a WLP is compared with that of a VCO using the on-chip inductor. The VCO design is optimized from the high-Q perspective to enhance performance. Through this optimization, less phase noise, lower power consumption, and a wider frequency tuning range are obtained simultaneously.
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Camiola, Vito Dario. "Subbands model for semiconductors based on the Maximum Entropy Principle." Doctoral thesis, Università di Catania, 2013. http://hdl.handle.net/10761/1313.
Повний текст джерелаАнотація:
In this thesis a double-gate MOSFET is simulated with an energy-transport subband model and an energy-transport model is derived for a nanoscale MOSFET.
Regarding the double-gate MOSFET the model is formulated starting from the moment system derived from the Schroedinger-Poisson-Boltzmann equations. The system is closed on the basis of the maximum entropy principle and includes scattering of electrons with acoustic and non-polar optical phonons. The proposed
expression of the entropy combines quantum effects and semiclassical transport by weighting the contribution of each sub band with the square modulus of the envelope functions arising from the Schroedinger-Poisson system. The simulations show that the model is able to capture the relevant confining and transport features and asses the robustness of the numerical scheme.\\
The model for the MOSFET takes into account the presence of both 3D and 2D electron gas included along with the quantization in the transversal direction with respect to the oxide at the gate which gives raise to a sub band decomposition of the electron energy.\\
Both intra and inter scattering between the 2D and the 3D electron gas are considered. In particular, a fictitious transition from the 3D to the 2D electrons and vice versa is introduced.
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McGarvey, Brian Scott. "Coupling of Solid-State and Electromagnetic Equations for the Computationally Efficient Time-Domain Modeling and Design of Wireless Packaged Geometries with NonlinearActive Devices." Thesis, Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/14551.
Повний текст джерелаАнотація:
This document contains a proposal for the creation of a simulator that can accurately model the interaction of electromagnetic (EM) and semiconductor effects for modern wireless devices including nonlinear and/or active devices.
The proposed simulator couples the balanced semiconductor equations (charge, momentum, kinetic energy) with a FDTD full-wave Yee-based electromagnetic (EM) simulator. The resultant CAD tool is able to model the response of one semiconductor device to both small signal and DC bias based on the process parameters (material, charge distribution and doping) without any a-priori knowledge of the device performance characteristics, thus making it extremely useful in modeling and integrating novel devices in RF and Wireless topologies. As a proof of concept an n+--i--n+ diode will be simulated. In the future, more complicated structures, such as MODFETs, will be modeled as well.
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Hascoët, Stanislas. "Mise en oeuvre de nouveaux matériaux d’assemblage dans les modules multipuces de puissance (MCM)." Thesis, Lyon, INSA, 2013. http://www.theses.fr/2013ISAL0123/document.
Повний текст джерелаАнотація:
L’introduction des composants grand gap dans le domaine de l’électronique de puissance requiert une optimisation de son environnement (packaging). En effet, les températures auxquelles peuvent être utilisés ce type de composants sont bien souvent plus grandes que celles supportables par le reste du module. De nouvelles techniques d’assemblage sont à l’étude et notamment certaines à base de frittage d’argent. Ces procédés présentent l’avantage de réaliser l’assemblage à une température modérée (similaire à celle d’une brasure), mais toutefois inférieure à celle de fusion de l’argent. La température de fusion du joint d’attache reste celle du matériau massif (plus de 900°C pour l’argent). Cette technique permet donc de réaliser des attaches pouvant fonctionner à très haute température. Ce travail de thèse a porté sur la mise en oeuvre d’une attache de puce par frittage d’argent. Après une étude des paramètres du procédé permettant d’obtenir la meilleure tenue mécanique (cisaillement), nous avons mis en évidence l’effet prépondérant de la finition des pièces à joindre. Lorsque la finition du substrat est de l’argent, aucun problème d’interface n’est observé et les assemblages sont fiables à t0 et en vieillissement. Généralement, la finition standard pour l’électronique de puissance est constituée d’une couche de nickel et d’or. Pour cette finition, le mécanisme semble différent selon l’épaisseur d’or présente sur le substrat ainsi que l’atmosphère utilisée pour le traitement thermique ou encore la charge appliquée. Globalement, plus l’épaisseur d’or est importante, moindre est l’accroche. Ce comportement semble fortement lié à la diffusion extrêmement rapide de l’argent en surface de l’or (et dans l’or). Cette diffusion a pour conséquence la formation d’une couche de solution solide or-argent. Cette couche a pour source de matière les grains d’argent qui permettent l’adhérence du joint d’argent fritté sur le substrat. Lorsque le volume d’or disponible pour la formation de cette couche est grand, la croissance de celle-ci est favorisée (en termes de surface et d’épaisseur). Cette croissance engendre une consommation des « piliers » d’argent et donc un affaiblissement de l’attache. L’application de pression semble augmenter fortement la concentration de piliers et améliore les résultats, tandis que sous azote, la diffusion de l’argent en surface de l’or semble inhibée, permettant l’obtention de bons résultats (à t0 et après cyclage). Ces résultats ont été mis en pratique pour la réalisation de plusieurs prototypes, dont l’un a été testé électriquement et ce de façon fonctionnelle à plus de 300°CUse of wide band gap chip in the power electronic industry requires an optimization of the close environment (packaging). Indeed, the can often sustain lower temperature than the die, especially the solder that are used to bond the parts of the module. Consequently, new bonding methods are investigated to enhance the performance of the packages. Silver sintering bonding technique is one the most promising. This method allow to bond parts at moderate temperature and the formed joint to operate at very high temperature (until the melting point of silver). This work is focused on the development of this bonding technique in the case of bonding a dies on a substrate. A study of the influence of the different parameters on the strength of the formed bond has been done. It revealed a major influence of the finishes of the bonded parts. Bonding on silver finished substrate results in good mechanical strength of the bond even after ageing. Furthermore, no interface issues are observed. However, the most used finish for power electronic is not silver but nickel-gold. Regarding this type of finish, the bond quality depends on the gold thickness, sintering profile and also sintering atmosphere. A solid solution of silver and gold seems to develop on the surface of the substrate, decreasing the section of the silver grains in contact with the substrate. Thus the mechanical strength of the assembly is decreased. This effect should be limited by the gold available for the Au-Ag solid solution growth. When sintering under nitrogen, the diffusion of silver on the gold surface is much lower than under air. Good results have been obtained with these configurations and even after ageing. Adding pressure during the thermal treatment seems also to minimize the phenomenon, probably by increasing the number of silver grains in contact with the substrate surface and so reducing the free surface for Au-Ag layer formation. Those results have been used to build prototypes, one of whom has been electrically tested with success at temperatures up to 300°C
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JURE, LIONEL. "Nanostructures sur substrat semiconducteur." Université Joseph Fourier (Grenoble), 2000. http://www.theses.fr/2000GRE10113.
Повний текст джерелаАнотація:
Cette these a pour sujet l'etude de la structure et de la formation d'objets unidimensionnels de taille nanometrique. Ce travail experimental a ete effectue a l'aide d'un microscope a effet tunnel (stm) fonctionnant a temperature variable sous ultravide, il a ete complete par des calculs ab initio (dft-lda). Les nanostructures que nous avons etudiees ont ete obtenues par depot de metaux (pb, in, sn) sur un substrat si(100) reconstruit (21). Apres une presentation succincte des techniques experimentales et du substrat si(100)21, nous presentons les resultats de l'etude statique par stm des depots (in et pb), au cours de laquelle nous avons precise le contraste stm des differents objets (precurseurs, terminaisons et structure interne des lignes de dimeres). Nous proposons un modele de structures pour ces objets en les comparant a ceux obtenus lors de l'etude prealable du depot si/si(100)21. Ensuite, nous nous interessons a la dynamique de ces depots a differentes temperatures. Ces observations nous permettent d'affiner notre modele de structure, de definir des mecanismes d'echange d'atomes. Nous avons elabore un modele de croissance des chaines de dimeres de plomb a partir des mesures a basse temperature. L'etude de depots recuits nous a permis de tester la stabilite des chaines et de mettre en evidence une interaction laterale entre chaines sans doute d'origine elastique mediee par le substrat. Enfin, nous avons etudie des codepots d'indium et d'etain dans le but de former un metal unidimensionnel sous la forme d'une ligne de dimeres mixtes (in-sn). Nous avons mis en evidence une selectivite chimique dans la formation des dimeres qui ne permet d'obtenir qu'un alliage unidimensionnel forme de dimeres homogenes des deux especes dans les chaines.
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Arnoult, Alexandre. "Dopage par modulation d'hétérostructures de semiconducteurs II-VI semimagnétiques en épitaxie par jets moléculaires." Université Joseph Fourier (Grenoble), 1998. http://www.theses.fr/1998GRE10237.
Повний текст джерелаАнотація:
Une etude theorique preliminaire a cette these a prevu que lorsque l'on introduit un gaz de trous bidimensionnel (2d) dans un puits quantique de semiconducteur semimagnetique, l'interaction entre les spins localises et les porteurs de charges induit une transition de phase ferromagnetique. Nous avons mis au point l'elaboration d'un tel systeme a base de tellurures en epitaxie par jets moleculaires, ainsi que la caracterisation au niveau microscopique des interfaces, du dopage et du transfert de porteurs dans le puits quantique. Ceci nous a permis d'elaborer des echantillons ayant donne lieu a toute une serie d'etudes physiques. Le dopage par modulation d'heterostructures de semiconducteurs ii-vi a base de tellure en epitaxie par jets moleculaires n'avait ete realise jusqu'a notre etude que pour un dopage de type n, sur des structures comportant du cdmgte comme materiau barriere, avec peu de magnesium. Or cet alliage est la clef de la realisation d'un bon confinement quantique dans les tellurures, surtout pour le dopage de type p ou la concentration en mg doit etre augmentee. L'utilisation d'une source d'azote ecr, dopant de type p, et l'optimisation des parametres de la croissance ont permis l'obtention d'un gaz de trous 2d de bonne densite, comme le montrent la spectroscopie optique, l'effet hall et la capacite-tension. L'etude de structures interdiffusees par sims, diffraction de rayon x et spectroscopie optique, nous a de plus permis de mieux comprendre les mecanismes de degradation en cours de croissance de nos couches comportant du magnesium, et dopees a l'azote. Un modele base sur la diffusion de l'azote a ete propose. Il a ensuite ete possible de realiser des structures semimagnetiques dans lesquelles l'interaction entre un gaz de trous 2d et des spins localises de manganese a permis la mise en evidence de la transition de phase ferromagnetique attendue theoriquement. Par ailleurs, un nouveau dopant de type n pour l'epitaxie par jets moleculaire des tellurures a ete teste avec succes sur des couches epaisses, ainsi que pour des heterostructures. Il s'agit de l'aluminium, dont le domaine d'utilisation est plus etendu que les autres dopants utilises jusqu'a present, puisqu'il permet d'obtenir une bonne efficacite meme sur des couches comportant du magnesium.
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Mueller, Ralph. "Specification and Automatic Generation of Simulation Models with Applications in Semiconductor Manufacturing." Diss., Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/16147.
Повний текст джерелаАнотація:
The creation of large-scale simulation models is a difficult and time-consuming task. Yet simulation is one of the techniques most frequently used by practitioners in Operations Research and Industrial Engineering, as it is less limited by modeling assumptions than many analytical methods. The effective generation of simulation models is an important challenge. Due to the rapid increase in computing power, it is possible to simulate significantly larger systems than in the past. However, the verification and validation of these large-scale simulations is typically a very challenging task.
This thesis introduces a simulation framework that can generate a large variety of manufacturing simulation models. These models have to be described with a simulation data specification. This specification is then used to generate a simulation model which is described as a Petri net. This approach reduces the effort of model verification.
The proposed Petri net data structure has extensions for time and token priorities. Since it builds on existing theory for classical Petri nets, it is possible to make certain assertions about the behavior of the generated simulation model.
The elements of the proposed framework and the simulation execution mechanism are described in detail. Measures of complexity for simulation models that are built with the framework are also developed.
The applicability of the framework to real-world systems is demonstrated by means of a semiconductor manufacturing system simulation model.
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Raszmann, Emma Barbara. "Series-Connection of Silicon Carbide MOSFET Modules using Active Gate-Drivers with dv/dt Control." Thesis, Virginia Tech, 2019. http://hdl.handle.net/10919/95938.
Повний текст джерелаАнотація:
This work investigates the voltage scaling feasibility of several low voltage SiC MOSFET modules operated as a single series-connected switch using active gate control. Both multilevel and two-level topologies are capable of achieving higher blocking voltages in high-power converter applications. Compared to multilevel topologies, two-level switching topologies are of interest due to less complex circuitry, higher density, and simpler control techniques. In this work, to balance the voltage between series-connected MOSFETs, device turn-off speeds are dynamically controlled on active gate-drivers using active gate control. The implementation of the active gate control technique (specifically, turn-off dv/dt control) is described in this thesis. Experimental results of the voltage balancing behavior across eight 1.7 kV rated SiC MOSFET devices in series (6 kV total dc bus voltage) with the selected active dv/dt control scheme are demonstrated. Finally, the voltage balancing performance and switching behavior of series-connected SiC MOSFET devices are discussed.Master of Science
According to ABB, 40% of the world's power demand is supplied by electrical energy. Specifically, in 2018, the world's electrical demand has grown by 4% since 2010. The growing need for electric energy makes it increasingly essential for systems that can efficiently and reliably convert and control energy levels for various end applications, such as electric motors, electric vehicles, data centers, and renewable energy systems. Power electronics are systems by which electrical energy is converted to different levels of power (voltage and current) depending on the end application. The use of power electronics systems is critical for controlling the flow of electrical energy in all applications of electric energy generation, transmission, and distribution. Advances in power electronics technologies, such as new control techniques and manufacturability of power semiconductor devices, are enabling improvements to the overall performance of electrical energy conversion systems. Power semiconductor devices, which are used as switches or rectifiers in various power electronic converters, are a critical building block of power electronic systems. In order to enable higher output power capability for converter systems, power semiconductor switches are required to sustain higher levels of voltage and current. Wide bandgap semiconductor devices are a particular new category of power semiconductors that have superior material properties compared to traditional devices such as Silicon (Si) Insulated-Gate Bipolar Junction Transistors (IGBTs). In particular, wide bandgap devices such as Silicon Carbide (SiC) Metal Oxide Semiconductor Field Effect Transistors (MOSFETs) have better ruggedness and thermal capabilities. These properties provide wide bandgap semiconductor devices to operate at higher temperatures and switching frequencies, which is beneficial for maximizing the overall efficiency and volume of power electronic converters. This work investigates a method of scaling up voltage in particular for medium-voltage power conversion, which can be applied for a variety of application areas. SiC MOSFET devices are becoming more attractive for utilization in medium-voltage high-power converter systems due to the need to further improve the efficiency and density of these systems. Rather than using individual high voltage rated semiconductor devices, this thesis demonstrates the effectiveness of using several low voltage rated semiconductor devices connected in series in order to operate them as a single switch. Using low voltage devices as a single series-connected switch rather than a using single high voltage switch can lead to achieving a lower total on-state resistance, expectedly maximizing the overall efficiency of converter systems for which the series-connected semiconductor switches would be applied. In particular, this thesis focuses on the implementation of a newer approach of compensating for the natural unbalance in voltage between series-connected devices. An active gate control method is used for monitoring and regulating the switching speed of several devices operated in series in this work. The objective of this thesis is to investigate the feasibility of this method in order to achieve up to 6 kV total dc bus voltage using eight series-connected SiC MOSFET devices.
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Liu, Yu [Verfasser], and Andreas [Gutachter] Lindemann. "Contribution to improve the EMI performance of electrical drive systems in vehicles with special consideration of power semiconductor modules / Yu Liu ; Gutachter: Andreas Lindemann." Magdeburg : Universitätsbibliothek Otto-von-Guericke-Universität, 2021. http://d-nb.info/1237047587/34.
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Niclot, Bernard. "Etude numerique de l'equation de boltzmann des semiconducteurs par methode particulaire." Palaiseau, École polytechnique, 1988. http://www.theses.fr/1988EPXXX002.
Повний текст джерелаАнотація:
Resolution de cette equation dans une geometrie simplifiee et demonstration de la validite de cette methode tant pour les modeles de collision lineaires (anteraction optique ou intervallee) que non-lineaires (prise en compte du principe de pauli, ou interaction interelectroniques). Une echelle numerique detaillee et une etude theorique de convergence et de stabilite viennent completer ces resultats