An analysis that is based on the monitoring of dynamic features from in-situ sensors of an industrial PECVD tool is presented. Linear Discriminant Analysis is used to determine which features are the most sensitive to various changes in the tool condition. The concept of Confidence Values (CVs) is used to quantify statistical changes of these dynamic features as the condition of the tool changed. Two data sets were collected from a PECVD tool in the facilities of a well-known equipment supplier. Dynamic features coming from the RF plasma power and matching capacitors’ sensors are shown to be sensitive to various changes in the cleaning cycles for Si-N, Si-O₂, and TEOS depositions. Quantifying the statistical distributions of the sensitive sensor features during tool condition changes is important for determining which sensor features are necessary to monitor in order to predict the tool chamber health. Results show that these RF plasma sensors could be used to track changes inside the tool chamber. / text

Proton Exchange Membrane Fuel Cell (PEMFC) is the most commonly used type of hydrogen fuel cell and a promising solution for vehicular and stationary power applications. This research starts with an extensive review of the PEMFC research, including experimental testing, and performance modeling, and performance degradation modeling using relatively accurate and easy-to-use mechanistic models. Next, a new PEMFC performance degradation model is introduced by amending the semi-empirical, mechanistic performance model to support the design and control of PEMFC systems and fuel cell electric vehicles (FCEVs). The new model takes into account critical factors impacting PEMFC performance. The performance degradation due to the oxidation of catalyst platinum (Pt) and loss of active surface area is captured by fitting the degradation model parameters using experimental data to capture the observed PEMFC performance fading. The new performance degradation model is then tested and further improved under the four typical load modes that a PEMFC system experiences in a vehicular application under regular driving cycles. The model is also fitted with PEMFC experimental degradation data under different load modes to improve modeling accuracy. The new model is applied and tested using simulations of a representative FCEV. The actual power load on an 80 kW PEMFC system in the modeled FCEV was obtained using the Advanced Vehicle Simulator (ADVISOR) under the US EPA Urban Dynamometer Driving Schedule (UDDS). With the ability to predict the operation life of the PEMFC, the appropriate sizes of the PEMFC system and the energy storage system (ESS) can be determined. Improved power control and energy management can be developed to extend the operation life of the PEMFC and lower the lifecycle cost of the FCEV. / Graduate

In this thesis, we develop several novel degradation models based on techniques from functional data analysis. These models are suitable for characterizing different types of sensor-based degradation signals, whether they are censored at a certain fixed time point or truncated at the failure threshold. Our proposed models can also be easily extended to accommodate for the effects of environmental conditions on degradation processes. Unlike many existing degradation models that rely on the existence of a historical sample of complete degradation signals, our modeling framework is well-suited for modeling complete as well as incomplete (sparse and fragmented) degradation signals. We utilize these models to predict and continuously update, in real time, the residual life distributions of partially degraded components. We assess and compare the performance of our proposed models and existing benchmark models by using simulated signals and real world data sets. The results indicate that our models can provide a better characterization of the degradation signals and a more accurate prediction of a system's lifetime under different signal scenarios. Another major advantage of our models is their robustness to the model mis-specification, which is especially important for applications with incomplete degradation signals (sparse or fragmented).

Un objectif important des études de la compatibilité électromagnétique (CEM) est de rendre les produits conformes aux exigences CEM des clients ou les normes. Cependant, toutes les vérifications de la conformité CEM sont appliquées avant la livraison des produits finis. Donc nous pourrions avoir de nouvelles questions sur les performances CEM des systèmes électroniques au cours de leur vie. Les comportements CEM de ces produits seront-ils toujours conformes dans plusieurs années ? Un produit peut-il garder les mêmes performances CEM pendant toute sa durée de vie ? Si non, combien de temps la conformité CEM peut-elle être maintenue ?L'étude à long terme de l'évolution des niveaux CEM, appelée "robustesse électromagnétique», est apparue ces dernières années. Les travaux précédents ont montré que la dégradation causée par le vieillissement pourrait induire des défaillances de système électronique, y compris une évolution de la compatibilité électromagnétique. Dans cette étude, l'évolution à long terme des niveaux CEM de deux groupes de composants électroniques a été étudiée. Le premier type de composant électronique est le circuit intégré. Les courants de hautes fréquences et les tensions induites au cours des activités de commutation de circuits intégrés sont responsables des émissions électromagnétiques non intentionnelles. En outre, les circuits intégrés sont aussi très souvent les victimes d'interférences électromagnétiques. Un autre groupe de composants est formé par les composants passifs. Dans un système électronique, les circuits intégrés fonctionnent souvent avec les composants passifs sur un même circuit imprimé. Les fonctions des composants passifs dans un système électronique, telles que le filtrage et le découplage, ont également une influence importante sur les niveaux de CEM.Afin d'analyser l'évolution à long terme des niveaux CEM des composants électroniques, les travaux présentés dans cette thèse ont pour objectif de proposer des méthodes générales pour prédire l'évolution dans les temps des niveaux de compatibilité électromagnétique des composants électroniques. / One important objective of the electromagnetic compatibility (EMC) studies is to make the products compliant with the EMC requirement of the customers or the standards. However, all the EMC compliance verifications are applied before the delivery of final products. So we might have some new questions about the EMC performance during their lifetime. Will the product still be EMC compliant in several years? Can a product keep the same EMC performance during its whole lifetime? If not, how long the EMC compliance can be maintained? The study of the long-term EMC level, which is called “electromagnetic robustness”, appeared in the recent years. Past works showed that the degradation caused by aging could induce failures of electronic system, including a harmful evolution of electromagnetic compatibility. In this study, the long-term evolution of the EMC levels of two electronic component groups has been studied. The first electronic component type is the integrated circuit. The high-frequency currents and voltages during the switching activities of ICs are responsible for unintentional emissions or coupling. Besides, ICs are also very often the victim of electromagnetic interference. Another group of components is the passive component. In an electronic system, the IC components usually work together with the passive components at PCB level. The functions of passive components in an electronic system, such as filtering and decoupling, also have an important influence on the EMC levels.In order to analyze the long-term evolution of the EMC level of the electronic components, the study in this thesis tends to propose general predictive methods for the electromagnetic compatibility levels of electronic components which evolve with time.

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