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The purpose of this thesis is to fabricate an LED module with low half intensity angle(HIA) ,and to use this module to form a line source with optical performance comparable to that of a CCFL .In addition ,heat dissipation of the LED module on different sub-mounts is also investigated . The LED modules were formed by first etching a through si via on silicon substrate using wet etching technology for light confining .Then a thin layer of metal was deposited on to the via to reflect the lights emitted from the LED .The LED die was attached to the Si sub-mount with electrodes ,and the connections between the LED and the Si sub-mount were completed by wire bonding .Finally ,the LED modules were obtained by positioning the Si substrates onto the Si sub-mounts using UV epoxy . The optical performance of the LED module was simulated by Lighttools .For the si substrate with a thickness of 400 £gm ,a simulated HIA of 36 o was obtained .Using six-LED package ,a 3-cm line source with 84.8% output uniformity was simulated .On the other hand ,the measured HIA of a LED module ,and the uniformity of 3-cm line source are 38 o and 84.8% ,respectively. The thermal resistance of the si sub-mounts were also investigated .The different structures of the sub-mount were proposed ,namely ,LED to Copper case ,LED to Si sub-mount to Copper case ,and LED to Si sub-mount with Copper filled via to Copper case .The estimated thermal resistance of the sub-mounts are 13 W/mk¡B19.4 W/mk and 34.7 W/mk .We believe that the large thermal resistance of the Si sub-mount with Copper filled via is primarily caused by 800 £gm thick substrate .

The fatigue-induced solder joint failure of surface mounted electronic devices has become one of the most critical reliability issues in electronic packaging industry. Prediction of the shape of solder joints has drawn special attention to the related development and engineering applications. Numerous solder joint models, based on energy minimization principle and analytical methods, have been proposed and developed. The methods are extensively utilized to the shape design of solder joint. However, it is important to find a suitable method to real applications. Herein, a series of experiments with different geometric parameters of SAC405 solder joints were carried out and the results were compared with the prediction by Surface Evolver Program. The changes of geometric shape with respect to different parameters of solder joint were also discussed. The influence of the geometric parameters, such as volume of solder joint, package weight, solder surface tension, and gravity force to the shape of solder joint were investigated. Two experiments with SAC405 solder balls were carried out. One is to observe the different reflowed geometry shape of solder balls with various volumes, and another is to observe the different reflowed geometry shape of solder balls with various loadings on them. The results show that the models made by Surface Evolver program are very similar to the real shapes observed by experiments, and the differences are between -3% ~ 6.5%. Thus, the results show that the predicted shapes are satisfactorily suitable. Finally, the predicted models by Surface Evolver program were also put into the ANSYS program, and preceded the fatigue life prediction due to thermal cycling tests. The comparison of the effect on fatigue life with respect to different geometry shapes is illustrated. The results show the shape of solder ball due to high loadings is better than that in thermal cycling tests.

No description available.

Les assemblages PoP pour « Package on Package » permettent d’augmenter fortement la densité d’intégration des circuits et systèmes microélectroniques, par superposition de plusieurs éléments semi-conducteurs actifs. Les interconnexions internes de ces systèmes sont alors soumises à des contraintes jamais atteintes. Nous avons pu identifier, caractériser, modéliser et simuler les mécanismes de défaillance potentiels propres à ces assemblages, et leur évolution : • Les gauchissements dans la phase d’assemblage du « PoP » et ses contraintes thermomécaniques sont plus importants que ceux de chacun des composants individuels. Un modèle analytique original a été construit et mis en ligne afin d’évaluer a priori ce gauchissement. • Les comportements hygroscopiques et hygromécaniques sont simulés et mesurés par une approche originale. L’assemblage « PoP » absorbe plus d’humidité que la somme des deux composants individuels, mais son gauchissement hygromécanique et ses contraintes hygromécaniques sont moins élevées. • Deux types d’essais de vieillissement accéléré sont réalisés pour étudier la fiabilité du « PoP » assemblé sur circuit imprimé : des cycles thermiques et des tests sous fort courant et température élevée. Dans ces deux types d’essais, l’assemblage d’un composant « top » sur un autre composant « bottom » pour former un PoP augmente les risques de défaillances. • L’évolution de la microstructure selon le type de vieillissement est comparée par des analyses physiques et physico-chimiques. Les fissures sont toujours situées dans l’interface substrat/billes, qui correspond aux zones critiques prédites par les simulations. / The assemblies PoP (Package on Package) can greatly increase the integration density of microelectronic circuits and systems, by vertically combining discrete semiconductor elements. The interconnections of these systems suffer the stresses never reached before. We were able to identify, characterize, model and simulate the potential failure mechanisms of these assemblies and their evolution: • The warpage in the assembly phase and thermomechanical stress of "PoP" are more serious than the individual components. An original analytical model has been built and put online for pre-estimating this warpage. • The hygroscopic and hygromechanical behaviors are simulated and measured by an original method. The assembly "PoP" absorbs more moisture than the sum of the individual components, but its hygromechanical warpage and stress are smaller. • Two types of accelerated aging tests are performed to study the reliability of "PoP" at the board level: the thermal cycling and the testing under current and temperature. In both types of tests, assembly a component "top" on another component "bottom" to form a “PoP” increases the risk of failure. • The microstructure evolution depending on the type of aging is compared by the physical and physico-chemical analysis. The cracks are always located in the interface substrate/balls, which corresponds to the critical areas predicted by the simulations.

End-users often complain about usability and safety problems in consumer packages. This study shows that these issues are an obstacle to the achievement of user satisfaction and to gain a competitive advantage in the market. To this end, a case study on food and beverage packages was done in order to identify and analyze these usability and safety problems based on the lifetime phases of packages in which end-users are involved. The study revealed that safety, clarity, legibility, visibility, storability, openability, re-closability, usefulness, and pleasantness are key areas where problems are widespread and should be considered by package developers and designers. The study also indicated that the problems occurred during use result from insufficiencies in current package design processes. These insufficiencies occur basically in the specification of the context of package use, identification of usability requirements, and the active involvement of the actual users in the package design processes. This study also highlights the need for a user-centered approach to package design in order to overcome the insufficiencies in current package design processes in a structured way and thus to achieve usable and safe packages. In addition, based on the literature and case study findings, checklists for user-centered package design process activities and for the design and evaluation of the packages are included. Moreover, a set of methods to be used during user-centered package design process is recommended.

ITC/USA 2011 Conference Proceedings / The Forty-Seventh Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2011 / Bally's Las Vegas, Las Vegas, Nevada / The F-22 Quick Response Package was designed to efficiently solve aircraft anomalies in the field. Providing this capability would enhance aircraft combat availability and lower maintenance costs. Using the current F-22 instrumentation flight test system design package as a baseline, a smaller, and much more versatile, version of the system was designed. This new design concept includes a data acquisition and recording system on a single pallet called the Quick Response Package (QRP). The QRP can be installed in any operational F-22 war fighter in a single production shift with no intrusion to the aircraft's systems readiness. The data acquisition and recording capabilities provide a near real-time field solution without excessive downtime or pilot intervention. This paper describes the design requirements, the design concept and packaging details of the QRP.

No description available.

Stability is a major requirement to draw reliable conclusions when interpreting results from supervised statistical learning. In this paper, we present a general framework for assessing and comparing the stability of results, that can be used in real-world statistical learning applications or in benchmark studies. We use the framework to show that stability is a property of both the algorithm and the data-generating process. In particular, we demonstrate that unstable algorithms (such as recursive partitioning) can produce stable results when the functional form of the relationship between the predictors and the response matches the algorithm. Typical uses of the framework in practice would be to compare the stability of results generated by different candidate algorithms for a data set at hand or to assess the stability of algorithms in a benchmark study. Code to perform the stability analyses is provided in the form of an R-package. / Series: Research Report Series / Department of Statistics and Mathematics

The main object of this thesis is to summarize legal regulation about package tour in czech legal order, define and describe subject of this contractual relationship, define contracting parties and individual rights and duties that are being established at the beginning or during this contractual relationship. Basic concepts linked to the package tour contract as well as the role of travel agency in the whole process are being analysed in this thesis. I also focused on the most important changes connected with passing of the New Civil Code when individual provisions are examined and their significance is explained. Similarly as a legal ground of this contractual type the directive 90/314 EEC is also being examined. Finally, this thesis evaluates whether implementation of this directive to czech legal order has been done correctly and whether czech laws comply with the basic rules this directive is based on. The thesis is composed of nine chapters, each of them dedicated to individual issue. In the introduction I define basic objective of this thesis. The following chapter focuses on the basic definiton, purpose, basic concepts and character of this contractual relationship. In the third most comprehensive chapter I analyse concrete requirements of package tour contract, individual rights and duties...