Thesis (M.S.)--State University of New York at Binghamton, Department of Systems Science and Industrial Engineering, Thomas J. Watson School of Engineering and Applied Science, 2008. / Includes bibliographical references.

Thesis (M.S.)--State University of New York at Binghamton, Thomas J. Watson School of Engineering and Applied Science, Department of Mechanical Engineering, 2009. / Includes bibliographical references.

Thesis (M.App.Sc.) - Carleton University, 2007. / Includes bibliographical references (p. 90-92). Also available in electronic format on the Internet.

Thesis (M.S.)--State University of New York at Binghamton, Department of Systems Science & Industrial Engineering, 2005. / Includes bibliographical references.

Thesis (Ph. D.)--State University of New York at Binghamton, Department of Systems Science and Industrial Engineering, 2007. / Includes bibliographical references (leaves 203-208).

Made available in DSpace on 2015-12-10T14:24:39Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-08-27. Added 1 bitstream(s) on 2015-12-10T14:30:54Z : No. of bitstreams: 1 000853517.pdf: 10039902 bytes, checksum: fe50ea8c5730317d053572b1a9f96429 (MD5) / Quando equipamentos e dispositivos eletrônicos são desenvolvidos, o conhecimento de todas as características do projeto é imprescindível. Certos circuitos eletrônicos apresentam componentes com elevada dissipação térmica devido à potência, podendo acarretar problemas no produto desenvolvido. Os componentes eletrônicos, em sua maioria, apresentam um limite em relação à temperatura, tal propriedade é denominada temperatura de junção, temperatura na qual o die do componente eletrônico se encontra. Se a temperatura de junção for excedida, o componente eletrônico poderá apresentar um comportamento inadequado ou até mesmo a parada total de suas atividades. O ideal é que o projeto elétrico e térmico avancem concomitantemente no desenvolvimento do equipamento, de modo a se obter um produto otimizado. Uma maneira eficiente de avaliar o comportamento térmico dos equipamentos eletrônicos é através de simulações computacionais em softwares de Computational Fluid Dynamics (CFD). O emprego dessa ferramenta não é trivial pela dificuldade da elaboração do modelo numérico. Além disso, alguns valores dos parâmetros necessários do modelo numérico, muitas vezes, não são conhecidos. Um exemplo típico é a potência térmica dissipada dos componentes eletrônicos, não dos elementos passivos como resistores ou capacitores, mas dos circuitos integrados (CIs). Os CIs possuem uma estrutura interna complexa contendo milhares ou até milhões de transistores. Outro exemplo é a placa de circuito impresso (PCI) com vários componentes eletrônicos no seu interior. Neste contexto, esta tese propõe uma metodologia para a obtenção de um modelo numérico correlacionado que pode ser extrapolado para um cenário desejado e a partir deste conhecer o campo de temperatura e de velocidade do equipamento. A metodologia é baseada em uma correlação entre o modelo numérico simplificado e teste... / When electronic equipment and devices are developed, the knowledge of all the features of this project is essential. Some electronic circuits have components with high thermal power dissipation, which can cause problems to the product developed. The electronic components have a limit on the temperature, such property is called junction temperature. If the junction temperature is exceeded, the electronic components will display inappropriate behavior or even a complete stop their activities. Ideally, the electrical design and thermal design concurrently advance in the development of the equipment in order to obtain an optimum product. A efficient way to meet the thermal performance of electronic equipment is through computer simulations in Computational Fluid Dynamics (CFD) software. However make use of this tool can be difficult. The difficulty is creating the numerical model. For this procedure is necessary to know some variables that are unknown. The thermal power dissipation of electronic components, not resistors or capacitors, but integrated circuits that has in its interior a very complex structure containing thousands or millions of transistors is an example. The complex structures of the geometries to be modeled that are inside electronic components and PCBs are other examples. In this context, this thesis proposes a methodology based on numerical correlations and experimental tests in order to know the device's temperature range designed running in a desired situation. The methodology is based on a correlation between the simplified numerical model and experimental test. The thermal simulation methodology presented in this thesis brings contributions to the thermal management in the design of electronic equipment. The approach allows doing numerical simulations of equipment for a desired scene and the results assist in project analysis, particularly in reliability and lifetime of electronic ...

Made available in DSpace on 2015-01-26T13:21:17Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-05-23Bitstream added on 2015-01-26T13:30:46Z : No. of bitstreams: 1 000802084.pdf: 3923321 bytes, checksum: 997f72f9b8b27ceadc0ee7028bdaf6a3 (MD5) / Este trabalho apresenta uma proposta de modelagem de uma réplica térmica de placa de circuito impresso, feita a partir de componentes com potência conhecidas objetivando analisar a distribuição de temperatura e os processos de troca de calor quando elementos semelhantes são utilizados em conjunto nos sistemas eletrônicos, visto que com o aumento da necessidade de maior capacidade de processamento os componentes estão cada vez menores e dissipando muito mais calor. Os obstáculos aquecidos que simulam componentes constituem-se em um resistor comercial envolvido por resina especial para encapsulamentos eletrônicos. Este modelo será criado para ter suas equações governantes resolvidas em software comercial. A réplica térmica será representada por blocos, com diferentes dissipações de potências e áreas de troca de calor. Uma vez que o desempenho térmico global depende da dissipação térmica de cada bloco, a avaliação poderá dizer quais blocos contribuem para uma melhor eficiência na troca de calor. Os experimentos fornecerão os valores de temperaturas dos componentes e velocidades de escoamentos para serem comparados com o modelo computacional, e desta forma, o melhor modelo de turbulência que descreve a análise experimental poderá ser encontrado. Foi estudada também a aplicação da teoria dos coeficientes de influência entre componentes. Este trabalho é adequado para a identificação de problemas que se relacionam direta ou indiretamente com falhas em componentes eletrônicos devido à alta temperatura / This paper proposes a modeling of a thermal replica of the printed circuit board, made from components with known power aimed at analyzing the temperature distribution and the processes of heat exchange when similar elements are used together in the electronic systems, as that with the increasing need for higher processing components are smaller and more heat dissipating. The heated obstacles simulating components are in a trade resistor surrounded by special resin for electronic encapsulation. This model will be created to be their governing equations solved in commercial software. The thermal replica is represented by blocks with different power dissipation and heat exchange areas. Once the overall thermal performance depends on the thermal dissipation of each block, the evaluation can tell which blocks contribute to better efficiency in heat exchange. The experiments provide the values of the temperature and velocity components of flow to be compared with the computational model, and thus the turbulence model that best describes the experimental analysis can be found. The application of the theory of influence coefficients between components was also studied. This work is suitable for the identification of problems that relate directly or indirectly to failures in electronic components due to high temperature

Stretchable Electronics is an emerging class of electronics that allow electronics to be bent, conform, ex and stretch while still retaining its full functionality. Other than bending, existing and conforming, adding stretchability to electronic systems can open up a new frontier for a myriad of applications. Especially in the medical sector, these stretchable devices can increase the scope of monitoring and ease and comfort of the patient. All kinds of wearable devices can be based on these technologies to augment our daily lives. With the kind of state of art technology available to the common man today, the bar has already been set for the performance of such devices. Hence, its imperative that these stretchable devices perform at this level and should be capable of adapting to the market to serve the mass requirement. Hence, it becomes inevitable to use metal interconnects to provide very low resistance and easy adhesion to commercial electronic components. Another aspect of such devices is an adhesion ability with which we can attach it to various kinds of surfaces. In this thesis, we propose a new multi-layered PDMS structure approach to bring stretchability in the device. For all kinds of adhesion requirements, various ratios of PDMS: Cross-linker have been used. These different ratios of PDMS: Cross-linker changes the mechanical and adhesive properties of the cured PDMS. Hence, the same material can be used as the stretchable substrate as well as to serve various adhesion requirements. A soft adhesion allows us to attach it to the human body/other surfaces. The adhesion can be tailored to be quite conformal and strong, yet its removal is quite gentle to the skin. A higher curing ratio makes the PDMS very sticky and soft. Aluminum/Copper foils can be directly stuck upon it and tracks can be then etched out to get a printed circuit. Since this adhesive layer is quite soft, it acts as a cushion and reduces the amount of stress transferred to the metal interconnects. Hence, stretchable circuits with metal interconnects can be realized. The electronic components can be then attached upon it via normal soldering techniques/using conductive ink. Various devices that can be built with the proposed techniques have been coined the term CAS (Conformal Active Sheets) to allow easy reference to such kind of devices. Since the substrate is soft, physical handling of such devices becomes an issue as one tries to transfer the circuit pattern. Hence, direct etching of the metal foil was explored via high pulsed current discharge technique. A CNC machine was also designed to try various ways of direct etching of the metal foil in an accurate and repeatable fashion.

Sn/Pb solders are widely used by the electronics industry to provide both mechanical and electrical interconnections between electronic components and printed circuit boards. Solders with enhanced mechanical properties are required for high reliability for Surface Mount Technology (SMT) applications. One approach to improve the mechanical properties of solder is to add metallic or intermetallic particles to eutectic 63Sn/37Pb solder to form composite solders. Cu6Sn5 and Cu3Sn form and grow at the solder/copper substrate interface. The formation and growth of these intermetallics have been proposed as controlling mechanisms for solderability and reliability of solder/copper joints. The goal of this study was to investigate the diffusion kinetics and microstructures of six types of composite solder/copper joints.

No description available.