The subject of this thesis is a new chip to substrate interconnection technique using self-aligning elastic chip sockets. This work was focused on the technology steps which are necessary to fulfill in order to realize the suggested technique. Elastic chip sockets offer a solution for several assembly and packaging challenges, such a thermo-mechanical mismatch, effortless rework, environmental compatibility, high interconnection density, high frequency signal integrity, etc. Two of the most challenging technology aspects, metallization and etching of the silicone elastomer were studied, but also, air bubble free casting of the silicone elastomer was taken into consideration. Elastic chip sockets and single elastic micro-bump contacts of different shapes and sizes were manufactured and characterized. The contact resistance measurements revealed that the elastic micro-bump contacts manufactured by using the developed methods require less than one tenth of the contact force to achieve the same low contact resistance as compared to commercial elastic interconnection structures. The analysis and measurements of the high frequency properties of the elastic micro-bump structures have shown that they can operate up to several tens of GHz without a serious degradation of the signal quality. The same methods were applied to manufacture very high density contact area array (approximately 80000 connections/cm2), which until now was achieved only using so called chip-first techniques. The low contact resistance, the absence of environmentally harmful materials, no need of soldering, easy rework as well as capability of very high interconnecting density and very high frequency compatibility, indicates a high potential of this technique for assembly and packaging. Moreover, the presented technology of the silicone elastomer micromachining (metallization and RIE in particular) can be used for manufacturing of other microstructures, like chemical or biological micro reactors. / QC 20110114

<p>The subject of this thesis is a new chip to substrate interconnection technique using self-aligning elastic chip sockets. This work was focused on the technology steps which are necessary to fulfill in order to realize the suggested technique. Elastic chip sockets offer a solution for several assembly and packaging challenges, such a thermo-mechanical mismatch, effortless rework, environmental compatibility, high interconnection density, high frequency signal integrity, etc.</p><p>Two of the most challenging technology aspects, metallization and etching of the silicone elastomer were studied, but also, air bubble free casting of the silicone elastomer was taken into consideration. Elastic chip sockets and single elastic micro-bump contacts of different shapes and sizes were manufactured and characterized.</p><p>The contact resistance measurements revealed that the elastic micro-bump contacts manufactured by using the developed methods require less than one tenth of the contact force to achieve the same low contact resistance as compared to commercial elastic interconnection structures.</p><p>The analysis and measurements of the high frequency properties of the elastic micro-bump structures have shown that they can operate up to several tens of GHz without a serious degradation of the signal quality.</p><p>The same methods were applied to manufacture very high density contact area array (approximately 80000 connections/cm2), which until now was achieved only using so called chip-first techniques.</p><p>The low contact resistance, the absence of environmentally harmful materials, no need of soldering, easy rework as well as capability of very high interconnecting density and very high frequency compatibility, indicates a high potential of this technique for assembly and packaging.</p><p>Moreover, the presented technology of the silicone elastomer micromachining (metallization and RIE in particular) can be used for manufacturing of other microstructures, like chemical or biological micro reactors.</p>

No description available.

Techn. Hochsch., Diss., 2006--Aachen.

Submitted by Johnny Rodrigues (johnnyrodrigues@ufcg.edu.br) on 2018-04-18T17:17:40Z No. of bitstreams: 1 WALFREDO DA SILVA CALMON - DISSERTAÇÃO PPG-CEMat 2014..pdf: 2111423 bytes, checksum: e64a02519d1c3b8005ac197552feadca (MD5) / Made available in DSpace on 2018-04-18T17:17:40Z (GMT). No. of bitstreams: 1 WALFREDO DA SILVA CALMON - DISSERTAÇÃO PPG-CEMat 2014..pdf: 2111423 bytes, checksum: e64a02519d1c3b8005ac197552feadca (MD5) Previous issue date: 2014-08-14 / Este trabalho tem por objetivo avaliar membranas de silicone que envolve o implante mamário preenchido com gel de silicone, no intuito de verificar a conformidade das suas propriedades. Como estratégia utilizou-se das técnicas de caracterização para analisar os parâmetros físico-químicos em três lotes diferentes de implante mamário. Os resultados experimentais encontrados foram comparados com valores referenciados em padrões estabelecidos em norma ou na literatura. Com isso, foi possível analisar alguns atributos que influenciam na qualidade desses implantes. Os resultados de microscopia por MO e MEV não detectaram anomalias nas superfícies das amostras. Foram detectados pelo ensaio de espectroscopia por EDS os elementos carbono, silício e oxigênio, como também identificados os metais ferro, cálcio, níquel e cromo nas amostras ensaiadas. O teste de alongamento de duas amostras não atendeu o requisito normativo. Conclui-se, portanto, que a integridade das membranas de silicone foi comprometida, por conta do seu comportamento mecânico, em duas das três amostras ensaiadas. / This work aims to evaluate silicon membranes surrounding the breast implant filled with silicone gel, in order to verify the conformity of its properties. As a strategy, we used the characterization techniques to analyze the physicochemical parameters in three different batches of breast implant. The experimental results were compared with values referenced in standard or standards established in the literature. Thus, it was possible to analyze some attributes that influence the quality of these implants. The results of OM and SEM microscopy did not detect anomalies in the surfaces of the samples. Were detected by testing the EDS spectra of carbon, silicon and oxygen elements, also identified as metals iron, calcium, nickel and chromium in the test samples. The stretching test two samples did not meet the regulatory requirement. Therefore, it is concluded that the integrity of the silicone membranes was compromised, because its mechanical behavior, in two of the three samples tested.

Submitted by Maria Medeiros (maria.dilva1@ufcg.edu.br) on 2018-07-12T11:18:08Z No. of bitstreams: 1 ALYSSON ANTÔNIO RIBEIRO GOMES - DISSERTAÇÃO (PPGCEMat) 2015.pdf: 3273281 bytes, checksum: b71940c4b95418d315f4cfe0dfe1600a (MD5) / Made available in DSpace on 2018-07-12T11:18:08Z (GMT). No. of bitstreams: 1 ALYSSON ANTÔNIO RIBEIRO GOMES - DISSERTAÇÃO (PPGCEMat) 2015.pdf: 3273281 bytes, checksum: b71940c4b95418d315f4cfe0dfe1600a (MD5) Previous issue date: 2015-06-11 / Os implantes mamários são dispositivos médicos, empregados para aumentar, reconstrutir ou corrigir anomalis congênitas mamárias. Normalmente, são preenchidas por gel de silicone e/ou solução salina. Atualmente, têm sido utilizados com frequência implantes mamários com a superfície externa da membrana texturizada, por apresentar maior seguraça e reduzir complicações pós-operatórias como as contraturas capsulares. Desta forma, este trabalho teve como objetivo avaliar as propriedades físicas, químicas e biológicas de implantes mamários com membrana texturizada e preenchidas com gel de silicone. Portanto foram analisados quatro implantes mamários, de dois diferentes fabricantes, sendo uma marca nacional e outra importada. Os ensaios de caracterização foram realizados no lado da membrana interno que fica em contado com o gel e no lado externo que fica em contato com o meio biológico, através das seguintes técnicas: Microscopia Óptica – MO, Microscopia Eletrônica de Varredura – MEV, Espectroscopia por Energia Dispersiva de Raios X - EDS, Retilineidade, Ensaios Dimensionais - Espessura, Ensaio Mecânico - Tração, Citotoxicidade e Coesividade do Gel. Nos resultados do ensaio de avaliação morfológica (MO e MEV) foi observado que a superfície das membranas em contato com o gel apresenta-se com textura lisa e uniforme já o lado externo da membrana observou-se presença de poros com tamanhos e formas bastante distintas. Em relação aos ensaios mecânicos, todas as amostras atenderam aos requisitos normativos, porém uma das amostras apresentou valor muito próximo do limite de aprovação. Observou-se que a texturização das superfícies influencia nos desempenhos mecânicos das membranas. Os resultados do ensaio de coesividade do gel de preenchimento, citotoxicidade e de elementos químicos contaminantes foram semelhantes em todas as amostras e estão de acordo com as normas de certificação, sendo X2 muito próximo ao limite de aprovação. / Silicone breast implants are medical devices used to increase, reconstruct or correct mammary congenital deformities. Typically, they are filled with silicone gel and / or saline solutions. Currently, there is often used breast implants with the outer surface of the textured membrane to present maximum security and reduce post-operative complications such as capsular contracture. Thus, this study aimed to evaluate the physical, chemical and biological properties of textured silicone gel breast implants. Four breast implants were analyzed, two different manufacturers. The characterization tests were performed on the inner side of the membrane which is in contact with the gel, and the external side, in contact with the biological environment, through the following techniques: optical microscopy - MO, Scanning Electron Microscopy - SEM, Spectroscopy Energy Dispersive X-ray - EDS, Straightness, Dimensional Testing - Thickness, Mechanical Testing - Traction, Cytotoxicity and cohesiveness gel. The results of the morphological evaluation test (OM and SEM) it was observed that the surface of the membrane in contact with the gel appears with smooth and uniform texture, however, the external side of the membrane was observed pores with very different sizes and shapes . Regarding the mechanical tests, all samples met the regulatory requirements, but one of the samples showed a value close to approval limit. It was observed that the texturing of suferfícies influences the mechanical performances of the membranes. The cohesiveness filling gel test, cytotoxicity and chemical contaminants were similar in all samples and comply with certification regulations.

Various silicone elastomers have been evaluated for use in the prosthetic reconstruction of facial defects. Their strength, texture, flexibility, hardness, ease of preparation, pigment receptivity and retention, and their resistance to cleaning were compared and the data consulted when an elastomer was chosen to restore defects, improve aesthetics and reestablish the confidence of a selection of patients. Detailed case reports are provided, together with information on the adhesives or mechanical methods available for retaining the facial prosetheses. Cyanoacrylate adhesives for use on skin surfaces and as tissue adhesives have been studied in detail. A novel n-butyl 413 cyanoacrylate has been developed with a viscosity, haemostatic property and stability to make it particularly suitable for use in skin grafting and tissue repair. It has already been used with good results on patients with severe burns. An improved formulation, containing a fluorescent dye, can be precisely applied through a specially constructed foot-controlled dispenser illuminated by a fibre-optic supplying UV-light. Cyanoacrylates are already being used as tissue adhesives in place of the conventional but potentially disfiguring suture. The availability of improved, imperceptible adhesives and a precision applicator, which can be used in a modern operating theatre, will extend their effectiveness and satisfy some of the needs of Plastic, and Oral and Maxillo-Facial Surgeons. Portable applicators have potential use in battlefield and in veterinary surgery and overcome the imprecision characteristic of earlier methods.

Various silicone elastomers have been evaluated for use in the prosthetic reconstruction of facial defects. Their strength, texture, flexibility, hardness, ease of preparation, pigment receptivity and retention, and their resistance to cleaning were compared and the data consulted when an elastomer was chosen to restore defects, improve aesthetics and reestablish the confidence of a selection of patients. Detailed case reports are provided, together with information on the adhesives or mechanical methods available for retaining the facial prosetheses. Cyanoacrylate adhesives for use on skin surfaces and as tissue adhesives have been studied in detail. A novel n-butyl 413 cyanoacrylate has been developed with a viscosity, haemostatic property and stability to make it particularly suitable for use in skin grafting and tissue repair. It has already been used with good results on patients with severe burns. An improved formulation, containing a fluorescent dye, can be precisely applied through a specially constructed foot-controlled dispenser illuminated by a fibre-optic supplying UV-light. Cyanoacrylates are already being used as tissue adhesives in place of the conventional but potentially disfiguring suture. The availability of improved, imperceptible adhesives and a precision applicator, which can be used in a modern operating theatre, will extend their effectiveness and satisfy some of the needs of Plastic, and Oral and Maxillo-Facial Surgeons. Portable applicators have potential use in battlefield and in veterinary surgery and overcome the imprecision characteristic of earlier methods. / Loctite UK

3D printing technology, which has its origins in rapid prototyping, is increasingly used to build functional devices. Although 3D printing technology has been well developed for thermoplastic polymers and metals, it is still in the research phase for soft polymeric materials such as silicones. Silicones are an industrially vital polymer characterized by a broad spectrum of chemical and physical properties for several smart applications, including on skin printing, smart sensors, multigradient material, and soft actuators. Extrusion-based multimaterial printing is one of the 3D printing techniques that have been adapted due to its compatibility to process silicone-based materials for constructing various functional devices. However, there are several challenges such as achieving on the fly mixing at low Reynolds numbers regime, achieving fast switching while using Newtonian/non-Newtonian inks, and achieving multimaterial printing on nonplanar surfaces. The development of suitable and robust printheads that are able to tackle those challenges can expand the application of this technology to a wide range of fields. In this thesis, several deposition-controlled printhead designs have been created for 3D printing multifunctional devices using an understanding of microfluidics. The established printhead can be controlled to formulate different multigradient structures through on the fly mixing during the material printing. Moreover, the developed printhead can be adapted to print multi viscous inks with high switching rates up to 50 Hz. Through the developed system, the printhead was able to track topologies in real-time, allowing objects to be printed over complex substrates. These new capabilities were applied to fabricate functional structures in order to demonstrate the potential of the developed printhead approaches that can be used in various applications, including smart sensors, soft robotics and multigradient objects. / Thesis / Doctor of Philosophy (PhD) / 3D printing techniques, such as extrusion-based multimaterial printing, have recently been utilized to process silicones due to their versatility in different smart applications, including multigradient material and soft actuators. Although it represents significant progress, there are still several challenges, including the proper mixing during printing with a laminar flow regime, the fast switching between different inks, and the printing over complex topographies. Therefore, various printhead designs have been developed in this thesis to tackle these challenges. In particular, a mixer printhead has been designed to allow mixing during printing for building multigradient objects. Also, a scalable printhead has been developed to allow fast switching for creating pixelated structures. Finally, a simple mechanical system has achieved multimaterial printing over various nonplanar surfaces. To the best of the author's knowledge, the developed printheads can be used in many fields, such as soft robotics and smart devices.

Ces travaux de thèse portent sur le développement d’un joint silicone pour la connectique dans l’aéronautique. Ce joint silicone doit être résistant aux solvants ainsi qu’aux huiles susceptibles de rentrer en contact avec celui-ci, et posséder de bonnes propriétés thermiques et mécaniques. Pour ce faire, les paramètres influençant ces propriétés ont été étudiés, comme la composition de la matrice, les conditions de sa réticulation et la formulation via différentes charges. Des matériaux silicones tels que le polydiméthylsiloxane (PDMS) et le polytrifluoropropylméthylsiloxane (PTFPMS) ont été sélectionnés pour composer la matrice. Leur flexibilité, leur large plage de température d’utilisation ainsi que leur excellente résistance aux attaques chimiques en font des matériaux de choix pour ce genre d’application. L’étude des mélanges de PDMS et de PTFPMS a démontré que les proportions idéales sont de 70/30 PDMS/PTFPMS. Le type de mélangeur sélectionné est une calandre bi-rouleaux, dont les rouleaux sont chauffés à 40°C. La réticulation de la matrice a été le sujet d’une étude approfondie. La cinétique de réticulation a été étudiée et l’influence des paramètres de réticulation tels que la température de réticulation, la nature et la quantité de peroxyde sur les propriétés finales ont été discutées. Finalement, l’influence de l’ajout de différentes charges sur le gonflement, la résistance thermique et les propriétés mécaniques de l’élastomère a été étudiée afin d’élaborer la formulation du joint silicone. / Polydimethylsiloxane (PDMS) and polytrifluoropropylmethylsiloxane (PTFPMS) elastomers are popular material in the aeronautic and connector fields. Their flexibility, wide service temperature range and chemical resistance make them first-choice materials for such applications. PTFPMS provides oil and apolar solvent resistance to the final material, while PDMS provides resistance to polar solvents, greater thermal resistance than PTFPMS, and cost reduction. Typically, connector seals comprising PDMS and PTFPMS can be composed of blends of homopolymers, of copolymers or of blends of homopolymers and copolymers. This present work deals only with blends of homopolymers. First, commercial PDMS and PTFPMS bases were selected and characterised, the blending process chosen and the PDMS/PTFPMS ratio tuned so as to minimise swelling in acetone and methylcyclohexane while maximising thermal properties. The optimal blend composition comprised 30 wt% PTFPMS. The second part of this work explored the influence of crosslinking conditions on final properties of the cured PDMS/FS blend. Crosslinking parameters, such as the temperature (160 and 180°C), the nature (DCP and DBPH) and the quantity (0.5 and 1 wt%) of peroxide, were varied. It appeared that co vulcanisation between PDMS and PTFPMS, occurs in certain conditions. Swelling as well is influenced by crosslinking conditions but not thermal properties. Finally, the formulation of the ideal elastomer was developed. Fillers, such as TiO2, CaCO3, quartz, CeO, a pigment, Fe2O3 and a platinum compound, were selected and their influence on thermal, mechanical and swelling properties studied. Regarding thermal and solvent properties, a high loading of fillers is a good strategy, however, an increase of permanent set was observed with the augmentation of filler fraction. Final formulations were selected for the compromise they offered between thermal and swelling properties and mechanical behaviour on the lab scale. Morphology observation revealed well dispersed domains, comparable to that of the non additivated blend.