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Khader, Iyas [Verfasser]. "Damage mechanisms in silicon nitride rolling tools applied in caliber rolling copper and steel wires / Iyas Khader." Aachen : Shaker, 2010. http://d-nb.info/1081885637/34.
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FERNANDES, MARCOS G. "Obtanção de fios em ligas cobre-magnésio para utilização em linhas de transmissão de energia elétrica." reponame:Repositório Institucional do IPEN, 2010. http://repositorio.ipen.br:8080/xmlui/handle/123456789/10030.
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Made available in DSpace on 2014-10-09T12:33:59Z (GMT). No. of bitstreams: 0<br>Made available in DSpace on 2014-10-09T14:01:16Z (GMT). No. of bitstreams: 0<br>Dissertação (Mestrado)<br>IPEN/D<br>Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP
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Johnston, Martin David. "Current and field distribution in high temperature superconductors." Thesis, Imperial College London, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.298870.
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Araújo, Mishene Christie Pinheiro Bezerra de. "Reciclagem de fios e cabos elétricos." Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/3/3133/tde-05092006-135800/.
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A indústria eletro-eletrônica vem aumentando a quantidade de sucatas geradas anualmente. Por este motivo necessita-se de reciclagem, para que se evite o desperdício de matérias-primas e de recursos naturais não-renováveis. A maioria dos produtos eletro-eletrônicos não recebe tratamento pós-consumo sendo depositada em aterros sanitários junto com o resíduo doméstico.Os resíduos eletro-eletrônicos são caracterizados pela presença de metais distribuídos em placas de circuito impresso, fios e cabos elétricos e componentes eletrônicos em geral. No caso da reciclagem de fios e cabos ainda persistem práticas incorretas, como a queima do plástico para aproveitamento do metal, que elimina o polímero em vez de aproveitá-lo. A solução para este problema está no reaproveitamento destes metais e polímeros contidos nos resíduos eletro-eletrônicos. Assim, deixarão de ser perdidas quantidades de alumínio, cobre, e polímeros presentes nos cabos, os quais poderão gerar receitas para o processo, já que estes são indispensáveis ao processo de fabricação. O objetivo deste trabalho é estudar a reciclagem dos cabos tipo cordão paralelo e flexível através de operações unitárias de Tratamento de Minérios. O tratamento da sucata iniciou-se com a seguinte seqüência: moagem, separação granulométrica, separação em meio denso, separação eletrostática, atrição, bateamento e elutriação. Ao final destes processos observou-se que as operações unitárias utilizadas na pesquisa obtiveram concentrados de cobre com baixo grau de contaminação, porém com exceção da elutriação, todas precisam de uma outra técnica para complementá-las. Com os resultados obtidos, concluiu-se que a moagem em moinho de facas com grelha de 3mm seguida de elutriação possibilita a separação do material polimérico, assim como, a obtenção de um concentrado de cobre.<br>The electro-electronics industry follows increasing the amount of scraps annually generated. For this reason it is necessary to recycle, so that it prevents the waste of raw materials and not renovable natural resources. The majority of the electro-electronic products do not receive any treatment after use and is disposed in municipal landfills together with solid wastes (MSW). The electro-electronic wastes are characterized by metal presence distributed in printed circuits, wires and cables and electronic components in general. In the case of the recycling of wires and cables incorrect practices still persist, as the burning of the plastic for recovery of the metal, thus eliminating the polymer instead of using it to advantage. The solution for this problem is in the recovery of the metals and polymers contained in the electro-electronic wastes. Thus, amounts of aluminum, copper, and polymers contained in the cables will not be lost, that way they will be able to generate resources for the process, since these substances are indispensable to the manufacture process. The objective of this work is to study the recycling of the parallel and flexible cables through Mineral Processing unit operations. The treatment of the scrap was initiated with the following sequence: grinding, size classification, density separation, electrostatic separation, attrition, panning and elutrition. To the end of this process concentrate conductor of copper with low degree of contamination were achieved. However, with exception of elutrition, all they need another technique to complement them. With the gotten results, it can be concluded that the milling in knives mill with 3mm grate followed of elutrition makes possible the separation of the polymeric material, as well as, the attainment of a copper concentrate.
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Sarvari, Reza. "Impact of size effects and anomalous skin effect on metallic wires as GSI interconnects." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/31636.
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Thesis (Ph.D)--Electrical and Computer Engineering, Georgia Institute of Technology, 2009.<br>Committee Chair: Meindl, James D.; Committee Member: Davis, Jeffrey A.; Committee Member: Gaylord, Thomas K.; Committee Member: Hess, Dennis W.; Committee Member: Peterson, Andrew F. Part of the SMARTech Electronic Thesis and Dissertation Collection.
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Sathler-Zanda, Renata. "Avaliação da deflexão elástica de fios ortodônticos de níquel-titânio, calibre 0,014." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/25/25144/tde-05112012-215337/.
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PROPOSIÇÃO: O objetivo desta pesquisa foi apresentar a magnitude e a constância das forças liberadas por fios ortodônticos de níquel-titânio, usados para a correção dos apinhamentos dentários. Outro objetivo foi comparar os dois meios mais utilizados de avaliação da deflexão elástica destes fios: o teste de 3 pontos e o dispositivo de simulação clínica. MATERIAL E MÉTODOS: Foram avaliados 11 grupos de fios de liga predominantemente de níquel-titânio, calibre 0,014, de 6 marcas diferentes (Abzil convencional e termoativado; GAC convencional e termoativado; Morelli convencional e termoativado; Ormco CuNiTi; Orthometric convencional e termoativado e Orthosource convencional e termoativado), em teste de deflexão elástica, nas deflexões de 0,5; 1; 2 e 3mm. Uma máquina de ensaio universal INSTRON 3342, com célula de carga de 10N foi utilizada e, como protocolo, foi seguida a norma ISO 15.841. Para a análise estatística dos resultados foram utilizados os testes: Kolmogorov-Smirnov, para conferir se havia normalidade; teste t independente, para comparação dos resultados do teste de 3 pontos e dos resultados do dispositivo; e o teste ANOVA seguido do teste de Tukey, para comparações entre grupos. RESULTADOS: Houve diferença estatística entre os resultados gerados pelo teste de 3 pontos e os gerados pelo dispositivo. Por ser o teste indicado pela norma ISO citada, somente os resultados do teste de 3 pontos foram considerados. Todos os fios estudados apresentaram pseudoelasticidade em uma faixa de variação de força de até 40cN. Os grupos Abzil convencional, GAC convencional, Morelli termoativado, Ormco CuNiTi e Orthometric convencional apresentaram força dentro de uma faixa considerada ótima para a indução da movimentação dentária (50cN-100cN). Os fios termoativados liberaram forças mais leves que seus pares convencionais. CONCLUSÕES: Dentre os grupos estudados, aqueles que apresentaram pseudoelasticidade, forças dentro de uma faixa considerada ótima e homogeneidade de amostra, foram os grupos Morelli termoativado e Ormco CuNiTi.<br>OBJECTIVE: The purpose of this study was to present the magnitude and the constancy of the forces released by nickel-titanium orthodontic wires, used to treat dental crowding. Another purpose was to compare the most usual types of bending tests used to evaluate these wires: 3-point test and clinical simulation device. MATERIAL AND METHODS: Eleven groups of orthodontic nickel-titanium wires, caliber 0.014, of 6 different brands (Abzil conventional and heat-activated; GAC conventional and heat-activated; Morelli conventional and heat-activated; Ormco CuNiTi; Orthometric conventional and heat-activated and Orthosource conventional and heat-activated) were tested by bending test, at deflections of 0.5; 1; 2 and 3mm. A universal testing machine INSTRON 3342 with a 10N load cell was used and, in order to standardize the tests, the ISO 15.841 regulation was followed. Statistical analysis was performed using the subsequent tests: Kolmogorov-Smirnov to verify normality; independent t test to compare the results of the 3-point test and the results derived from the device, and ANOVA followed by the Tukey test for intergroup comparisons. RESULTS: There were significant differences between the results of the 3-point test and the device. As indicated by the ISO regulation, only the results from the 3-point bending test were considered. All groups were classified as pseudoelastic, within a load range of 40cN, at maximum. The groups Abzil conventional, GAC conventional, Morelli heat-activated, Ormco CuNiTi and Orthometric conventional released load within optimum range (50cN-100cN). Heatactivated wires released lower load compared to conventional wire of the same brand. CONCLUSIONS: Among the groups evaluated those that presented pseudoelasticity, load within a range considered optimal, in a homogeneous manner, were Morelli heat-activated and Ormco CuNiTi.
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Tardieu, Simon. "Fils conducteurs composites (microfils d'argent - cuivre) pour application en champs magnétiques intenses." Thesis, Toulouse 3, 2020. http://www.theses.fr/2020TOU30186.
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Le LNCMI-Toulouse produit les champs magnétiques non-destructifs pulsés parmi les plus puissants du monde (98,8 T). Les fils conducteurs utilisés dans les bobines qui génèrent ces champs magnétiques nécessitent une contrainte à la rupture élevée afin de résister aux forces de Lorentz. De plus, pour obtenir une durée d'impulsion la plus longue possible, ces conducteurs doivent avoir une résistivité électrique la plus proche possible de celle du Cu pur. Le LNCMI et le CIRIMAT explorent la conception et la préparation de fils nano-composites à matrice Cu par une combinaison de métallurgie des poudres, de frittage SPS et de tréfilage. Les poudres composites à faibles teneurs en Ag (< 10 % vol. Ag) sont préparées en dispersant des microfils d'Ag (diamètre 200 nm, longueur 30 µm) synthétisés au CIRIMAT dans une poudre commerciale de Cu sphérique (diamètre 0,5-1 µm). Les poudres ainsi obtenues sont consolidées par SPS sous forme de barreaux. Ceux-ci sont étirés sans rupture, jusqu'à l'obtention de fils fins (diamètre 1 - 0,2 mm) dont la microstructure est sous la forme de grains ultrafins de Cu (200 - 400 nm) allongés sur plusieurs micromètres dans le sens de l'étirage. Les microfils d'Ag sont dispersés le long des joints de grains du Cu. La mesure de la résistivité électrique et de la contrainte à la rupture des fils (à 293 K et 77 K) a permis de déterminer que les fils contenants seulement 1 % vol. Ag présentent le meilleur compromis contrainte à la rupture / résistivité (1100 MPa / 0,49 µÔmega.cm à 77 K). La formation d'un alliage Cu/Ag lors du frittage SPS a pour conséquence une augmentation notable de la résistivité électrique des fils et doit donc être évitée. Une matrice de Cu avec une distribution bimodale de la taille des grains permet de réduire la résistivité électrique tout en conservant une haute contrainte à la rupture (1080 MPa / 0,45 µÔmega.cm à 77 K). Les fils nano-composites Ag-Cu présentent une contrainte à la rupture équivalente à celle des fils d'alliage Cu/Ag contenant environ 20 fois plus d'Ag élaborés par fusion et solidification, mais présentent une résistivité électrique environ 1,5 fois plus faible<br>LNCMI-Toulouse produces some of the most intense non-destructive pulsed magnetic fields in the world (98.8 T). The wires used in coils which generate these magnetic fields require high ultimate tensile strength (UTS) in order to resist the Lorentz forces. Moreover, to obtain the longest possible pulse duration, these wires must have an electrical resistivity closest to that of pure Cu. LNCMI and CIRIMAT explore the design and preparation of Cu-based nanocomposite wires obtained by a combination of powder metallurgy, Spark Plasma Sintering (SPS) and wire-drawing. Composite powders with low Ag contents (< 10 % vol. Ag) are prepared by dispersing Ag microwires (diameter 200 nm, length 30 µm) synthesized at CIRIMAT in a commercial spherical Cu powder (diameter 0.5-1 µm). The so-obtained composite powders are consolidated by SPS in the form of cylinders. These cylinders are drawn, without breaking, in the form of fine wires (1 - 0.2 mm). The microstructure of the wires is made up of Cu ultrafine grains (200 - 400 nm) elongated over several micrometers in the drawing direction. Ag microwires are dispersed along the grain boundaries of Cu. The measurement of the electrical resistivity and the UTS of the wires (at 293 K and 77 K) shows that the wires containing only 1 vol. % Ag present the best compromise between high UTS and low electrical resistivity (1100 MPa / 0.49 µÔmega.cm at 77 K). The formation of Cu/Ag alloys during the SPS cycle significantly increases the resistivity of the wires and thus must be avoided. A Cu matrix with a bimodal grain size distribution makes it possible to reduce the electrical resistivity of the wires while keeping high UTS (1080 MPa / 0.45 µÔmega.cm at 77 K). Ag-Cu nanocomposite wires present high UTS, equivalent to that of Cu/Ag alloy wires containing about 20 times more Ag produced by melting and solidification, but their electrical resistivity is about 1.5 times lower
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Arnaud, Claire. "Fils conducteurs nanostructurés (cuivre et composites nanotube de carbone - cuivre) pour application en champs magnétiques intenses." Thesis, Toulouse 3, 2015. http://www.theses.fr/2015TOU30216/document.
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Afin de produire des champs magnétiques intenses (100 T), les fils conducteurs utilisés dans les bobines pulsées doivent présenter une contrainte à la rupture élevée et une très faible résistivité électrique. Le LNCMI et l'équipe NNC du CIRIMAT explorent des solutions originales basées sur l'élaboration de fils de cuivre nanostructuré et de fils nanocomposites nanotube de carbone - cuivre (NTC-Cu) par la combinaison originale du spark plasma sintering (SPS) et de l'étirage à température ambiante. Des barreaux de cuivre ont été élaborés par SPS à partir de poudres commerciales micrométriques. La croissance cristalline est très faible et la taille des grains de cuivre est 10 fois plus petite que celle des précurseurs de fils classiques. Les barreaux ont été étirés, sans rupture, sous forme de fils de diamètre décroissant (jusqu'à 0,198 mm) et de plusieurs mètres de long. Les grains ultrafins de Cu sont fortement allongés dans la direction de l'étirage. Aucune macle n'a été observée. Tous nos fils de cuivre présentent une résistance à la rupture en traction (à 293K et 77K) supérieure à celle des fils préparés à partir d'un précurseur de cuivre OFHC classique, ce qui pourrait résulter de la combinaison de l'écrouissage et des mécanismes d'Orowan. La résistivité électrique des fils est environ 12% plus élevée que celle des fils de cuivre OFHC. Pour les composites NTC-Cu, une adaptation de la méthode de mélange (fonctionnalisation des NTC biparois et à huit parois, mélange, cryogénisation, lyophilisation, réduction sous H2) a permis de produire des lots de poudre de 14 g en ayant une dispersion homogène des NTC. Du fait de la très faible teneur en carbone (= 1%), la préparation des barreaux puis des fils par les méthodes employées pour le cuivre pur est possible sans modification. La contrainte maximale à la rupture des fils NTC-Cu est supérieure (10-25%) à celle des fils de cuivre correspondants. Les NTC ont peu d'influence sur la microstructure du cuivre et leur probable alignement permet de bénéficier de leur grande résistance en traction. La résistivité est légèrement supérieure à celle des fils de cuivre correspondants (environ 12% à 77K). Le dernier chapitre est consacré à la préparation d'éprouvettes " os-de-chien " (Cu et NTC-Cu) directement par SPS " near-net-shape ". Nous avons mis en évidence l'influence de la nature du matériau dans lequel est usinée la matrice (graphite ou WC-Co) sur la microstructure, la microdureté et la contrainte à la rupture, pour un même cycle de frittage<br>In order to produce high magnetic fields (100 T), the conducting wires used in pulsed coils must show both a high tensile strength and very low electrical resistivity. The LNCMI and NNC team of CIRIMAT explore creative solutions based on the development of nanostructured copper wires and carbon nanotube - copper (CNT-Cu) nanocomposite wires by the original combination of spark plasma sintering (SPS) and room-temperature wire-drawing (WD). Copper cylinders were prepared by SPS of micrometric commercial powders. Crystal growth is very low and the copper grains size is 10 times lower than for conventional wire precursors. The cylinders were wire-drawn, without breaking, into wires of decreasing diameter (down to 0.198 mm) and several meters long. The ultrafine Cu grains are highly elongated in the WD direction. No twinning was observed. Our copper wires show an ultimate tensile strength (UTS) at 293K and 77K higher than those for wires prepared from conventional OFHC copper, which could result from the combination of strain hardening and Orowan mechanisms. The electrical resistivity is about 12% higher than those for the OFHC wires. For the CNT-Cu nanocomposites, an adaptation of preparation route (functionalization of double-walled and eight-walled CNTs, mixing, freeze-drying, H2 reduction) resulted in the production of 14 g powder batches with a homogeneous dispersion of the CNTs. Due to the very low carbon content (= 1%), the preparation of the cylinders and wires by the methods used for pure copper is possible without modification. The UTS of the CNT-Cu wirers is 10-25% higher than for the corresponding copper wires. The CNTs have little influence on the Cu microstructure and their probable alignment allows one to benefit from their high tensile strength. The electrical resistivity is only moderately higher than for the corresponding copper wires (about 12% at 77K). The last chapter was devoted to the preparation of "dog-bone" Cu and CNT-Cu test samples by "near-net-shape" SPS. We have brought to the fore the influence of the nature of the die (graphite or WC-Co) on the microstructure, microhardness and tensile strength, for the same sintering cycle
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Gross, David [Verfasser]. "Copper Metallization on Silicon Power Devices for Heavy Copper Wire-Bonding / David Gross." Aachen : Shaker, 2016. http://d-nb.info/1122546432/34.
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Zhang, Xiaodong. "Characterization of copper diffusion in advanced packaging /." View abstract or full-text, 2007. http://library.ust.hk/cgi/db/thesis.pl?MECH%202007%20ZHANG.
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Poole, Martin. "Progress towards the development and implementation of an unambiguous copper wire fingerprinting system." Thesis, Rhodes University, 2003. http://eprints.ru.ac.za/214/.
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Suchanek, Richard Donald III. "Breakdown Voltage Performances of Aluminum and Copper Conductor Wire Under Compression Stresses." TopSCHOLAR®, 2016. http://digitalcommons.wku.edu/theses/1606.
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In the global, competitive market of energy transformation, increased operational expenses and depletion of raw materials have resulted in companies pursuing alternate materials to reduce consumer costs. In electrical applications, energy is transformed using materials with high electrical conductive properties. The conductive material used to transmit a signal is called conductor wire and is comprised of any material that has the ability to move charged particles from one point to another without propagation or delay. The conductor wire in many applications is encapsulated in epoxy resin called enamel. The enamel is the insulation system that provides necessary dielectric clearances to prevent voltage leakage. The most common form of energy transformation is the electric motor. Both copper and aluminum conductor wire are commonly used in electric motors, but copper is preferred due to thermal and electrical properties. However, there is a significant economic incentive to convert to aluminum conductor wire. Limited white papers are available comparing the performances of the two materials; the research is limited to physical and electrical performances of the raw material and does not take into considering the insulation. The conductor wire, which includes the insulation, is susceptible to damage during the manufacturing process and is an inherent risk if not fully understood. During the blocking process, the conductor wire is pushed and compressed into lamination slots. This process changes the conductor wire outer diameter to accommodate void spaces within the lamination slots. The percentage of slot area occupied by the conductor wire is known as slot fill. The higher the slot fill, the more wire occupying the available space. The higher the slot fill, the more force required to fill the slots. High slot fill motor designs provide a performance advantage with little associated cost. The more wire pressed into the slot, the higher the potential efficiency gains. However, high slot fill motors are more susceptible to damage.
The study is designed to evaluate and measure the durability of aluminum and copper conductor wire under simulated compression stresses. Utilizing this information, electric motor manufacturers can push current design limits without affecting conductor wire quality and reliability.
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Trevizan, João Pedro Gonçalves. "Estudo da viabilidade técnica e econômica da substituição de fios de ouro por fios de cobre em memórias DRAM." Universidade do Vale do Rio dos Sinos, 2016. http://www.repositorio.jesuita.org.br/handle/UNISINOS/5523.
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Previous issue date: 2016-06-15<br>itt Chip - Instituto Tecnológico de Semicondutores da Unisinos<br>PADIS - Programa Federal de Apoio a Indústria de Semicondutores<br>Este estudo avalia uma proposta de substituição de fio de ouro por fio de cobre no processo de wire bonding em memórias DRAM DDR3 encapsuladas no Brasil. A viabilidade técnica da aplicação desta tecnologia para este componente foi testada na prática em uma empresa coreana, com a produção de amostras e verificação das características de qualidade das mesmas. Após otimização de parametros da primeira solda por DOE, foi possível obter resultados dentro das especificações do processo e semelhantes aos obtidos com o fio de ouro. Após a confirmação da viabilidade técnica, foi verificado a viabilidade econômica deste projeto, calculando o custo de implementação e estimando o tempo para retorno do investimento através dos métodos de payback simples e descontado. Devido à necessidade de aquisição de máquinas soldadoras de custo elevado, o payback descontado resultou em seis anos e onze meses, o que representa um risco alto considerando o dinamismo do mercado de semicondutores e a eminente substituição do encapsulamento BOC pela tecnologia de flip chip<br>This study evaluates the proposal of gold wire for copper wire replacement in the wire bonding process used in DRAM DDR3 memory packaging in Brazil. The technical feasibility of applying this technology to the component has been verifyed in practice on a Korean company, with the production of samples and the examination of quality characteristics, such as bond pull force and bond shear strenght, intermetallic compound and bonding pad structure. After parameters optimization of the first bond by DOE, it was possible to obtain results within process specifications and similar to those obtained with the gold wire. After confirming the technical feasibility, the economic viability of this project was verified by calculating the cost of implementation and the necessary time to recover the investment, through the simple and discounted payback methods. Because of the need of purchasing costly wire bonding machines, the discounted payback resulted in six years and eleven months, which represents a high risk investment, considering the semiconductor market dynamism and the imminent replacement of BOC package by flip chip technology.
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Auersperg, Jürgen, D. Breuer, K. V. Machani, Sven Rzepka, and Bernd Michel. "FEA to Tackle Damage and Cracking Risks in BEoL Structures under Copper Wire Bonding Impact." Universitätsbibliothek Chemnitz, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-207250.
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With the recent increase in Gold (Au) wire cost Copper (Cu) wire becomes an attractive way to manage overall package cost. On the other hand, Copper wire bonding introduces much higher mechanical impact to underlying BEoL structures and actives because of the higher stiffness and lower ductility of Copper compared to Gold. These trends are accompanied by the application of new porous or nano-particle filled materials like low-k and ultra low-k materials for Back-end of Line (BEoL) layers of advanced CMOS technologies. As a result, higher delamination and cracking risks in BEoL structures underneath bonded areas represent an increasing challenge for the thermo-mechanical reliability requirements. To overcome the related reliability issues the authors performed a two level nonlinear FEM-simulation approach. Initially nonlinear axi-symmetric modeling and simulation of the copper bonding process are coupled with a spatial simulation model of the whole BeoL and bond pad structure. Cracking and delamination risks are estimated by a surface based cohesive contact approach and the utilization of a crushing foam constitutive material model for ultra low-k materials.
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Spickett, Andrea. "The anthelmintic effect of copper oxide wire particle (COWP) boluses against Haemonchus contortus in indigenous goats in South Africa." Diss., University of Pretoria, 2009. http://hdl.handle.net/2263/22936.
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A field trial was conducted to test the anthelmintic effect of a single dose of 4g of copper oxide wire particles (COWP) in bolus form in indigenous goats belonging to small scale communal farmers in three areas in the Bergville district of Kwa-Zulu Natal Province, South Africa namely Dukuza, Ogade and Hoffenthal. Faecal egg counts (FECs) determined by both the McMaster and Pitchford–Visser methods, FAMACHA<br>Dissertation (MSc (Veterinary Tropical Diseases))--University of Pretoria, 2009.<br>Veterinary Tropical Diseases<br>unrestricted
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Spickett, Andrea. "The anthelmintic effect of copper oxide wire particle (COWP) boluses against Haemonchus contortus in indigenous goats in South Africa." Pretoria : [s.n.], 2010. http://upetd.up.ac.za/thesis/available/etd-03022010-133826/.
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Wu, Jie-Ting, and 巫玠廷. "The Study of Copper Nano-wires." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/67430679930692406015.
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碩士<br>國立清華大學<br>電子工程研究所<br>93<br>The purpose of this study was the fabrication and electrical measurement of copper nanowires. The patterns of copper nanowires were defined by electron beam lithography on amorphous-silicon. Then copper nanowires formed by replacement method in mixture solution of cupric sulfate (CuSO4•5H2O) with HF. After the fabrication of copper nanowire, we measured the electrical characteristic.
At first, the C60 mix with electron beam resist DSE1010 to make up the nanocomposite resist. The patterns were exposed with 40nm, 60nm, 80nm and 100nm iso-line with dose 5~14.75 μC/cm2. Then development time with 60s, 90s and 150s and concentration of C60 in nanocomposite resist with 0.015%, 0.025% and 0.035% were used to modify the exposure results. Then we found the concentration of C60 with 0.015% and development time 150s could fine define line width about 90nm. Among different concentration of HF in replacement solution and replacement time, which are 70c.c./L with 10s, 70c.c./L with 7s and 60c.c./L with 7s, the 60c.c/L with 7s gave the proper copper nanowire with width 92nm and thickness 62nm. There were two kinds of electrical measurement methods used. First kind was measured on Conductive mode of Atomic Force Microscopic(C-AFM). After the copper nanowires were fabricated by replacement method, copper film with thickness 4000Å was sputtered on one end. Then we got the I-V curve by used C-AFM. The second one was used probe station with HP4156A to measure the electrical characteristic. After the copper nanowires were fabricated, the metal mask was used to define the electrode pad during the copper film sputtered on it. The four point measurement method was used on probe station to avoid the contact resistance. Then, these two different methods were discussed to compare the advantages and disadvantages at the end.
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Shih, Ting Wei, and 施亭維. "The Preparation of Submicron Copper wires by Green Process." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/4nb28a.
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碩士<br>國立臺北科技大學<br>資源工程研究所<br>106<br>Submicron copper metal is an important material in the preparation of conductive paste. In this study, the green low temperature process of submicron copper wires was studied, and Vitamin C was used to replace the toxic hydrazine as a reducing agent.
The effects of reaction temperature, reducing agent concentration and capping agent concentration in the preparation of submicron copper wires under different reaction times were discussed. The experimental results show that in the presence of NaOH, Vitamin C can convert Cu2+ to Cu+ and finally convert to Cu, in which NaOH plays an important role in increasing the yield of metallic copper in the reaction, and submicron wire is prepared by capping agent .
More reducing agent, the wires becomes wider and longer and the yield increases, when the temperature is increased wires becomes shorter, denser and the yield is lower, and the more the capping agent is added, the longer, the denser and the lower the yield.
A set of optimized process parameters were obtained from the experimental data. The molar ratio of each additive was NaOH: Cu(NO3)2: EDA: Vitamin C = 1500:1:33:8.2. Submicron copper wires having an average line length of about 7.76 μm, an average wire diameter of about 266.67 nm, and the smallest inclusion particles and a yield of 99% was prepared by 3 hours at 70 ° C.
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Liu, Kuan-Heng, and 劉冠亨. "Microstructural Study on Molten Marks of Fire-Causing Copper Wires." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/12625707054911934804.
Full textAbstract:
博士<br>義守大學<br>材料科學與工程學系<br>104<br>The electrical fires are generally the main causes of building fires, but the public is not always convinced of the critical evidence adopted by the fire investigators to identify the electrical fires. Basically, the critical evidence used for the fire investigation departments to identify an electrical fire is mainly the short-circuited arc beads of wires at the fire scene. Unfortunately, the scientific definition of the "fire-causing arc bead" (FCAB) has not yet been clear due to the lack of thorough scientific investigations. Therefore, the verification of arc bead influences significantly the public reliance of the investigations as well as the evidence weight of judicial prosecution, litigation and judgment. This verification problem is necessarily an urgent issue for the fire agencies to tackle immediately.
This study analyzed the short circuit of a copper wire at ambient atmosphere. We scrutinized the microstructures of fire-causing electric wires and simulated the external environmental conditions required for the formation of FCABs. The experimental results revealed that when the copper wire was short-circuited and blown out, the molten copper liquid formed arc beads at the blown part under the effect of surface tension. In the solidification process, the FCABs can be divided into two categories (the non-oxygen-permeated arc beads and the oxygen- permeated arc beads) that exhibit two different kinds of molten marks at ambient atmosphere.
In this study of the non-oxygen-permeated FCABs, our metallographic investigation showed that the primary thermal dendrites of copper at the non-oxygen-permeated FCABs grew parallel to each other, but in the opposite direction to the heat flow. We derived the relationships of the undercooling (∆T0), the growth velocity (ν), and the primary spacing (λ) of the dendrites with respect to the wire’s diameters (D).
This study also explored the oxygen-permeated FCABs at ambient atmosphere, and successfully identified various phases of the oxygen-permeated FCAB. A cuprous oxide flake was formed on the surface of the molten mark during the rapid solidification process, and there were two microstructural constituents, namely Cu-κ eutectic structure and the solutal Cu dendrites. Due to the oxygen-permeated FCABs formed at atmosphere in the local equilibrium solidification process, the phases of oxygen-permeated FCABs segregated to the cuprous oxide flake, the Cu-κ eutectic and Cu phase solutal dendrites, which were the fingerprints of the oxygen-permeated FCABs.
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Chang, Jung-Chou, and 張榮洲. "The Influence of Drawing Passes on Mechanical Properties of Copper Wires." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/92206016031395809662.
Full textAbstract:
碩士<br>國立成功大學<br>機械工程學系專班<br>92<br>In this study, SCR (southwire continuous casting rod) copper rods of diameter 8.0mm are drawn continuously down to copper wires of 3.0mm diameter in drawing processes comprising various numbers of individual passes, 8-passes(reduction area: 21.8%/pass), 6-passes(reduction area: 27.9%/pass) and 7-passes(reduction area: 24.4%/pass). The influence of the number of drawing passes on the mechanical properties and fracture behavior of the copper wires is investigated. The “skin pass” effect is also studied. In order to investigate the mechanical properties, the deformed copper wires are grouped into four sets, and are tested using an universal testing machine and a Vickers hardness gauge to determine the variation of work hardening. The distortion of the copper grains and the fine and fiber textures in the cross-section and longitudinal sections are inspected and observed using OM instrumentation. Meanwhile, the preferred orientation of the grains is measured by the EBSD (electron back-scattered diffraction) technique to establish the relationship between the orientation and the mechanical properties. Finally, the specimens are observed with SEM to identify the fracture characteristics and mechanisms. The current results reveal that the different drawing passes have specific effects on the mechanical properties of the copper wires. Specifically, the flow stress, Vickers hardness and Young’s modulus increase with increasing strain, while the breaking strain decreases. The EBSD measurement indicates that the <111> orientation increases with increasing strain, while the <100> orientation decreases. In the final pass of the 6-passes set, the flow stress, Vickers hardness and Young’s modulus decrease, while the breaking strain increases. Furthermore, it is evident that the copper exhibits dynamic recovery and recrystallization due to a less intense <111>. Comparing the 8-passes and 9-passes drawing sets, it is clear that the “skin pass” enhances the tensile strength due to a higher ratio of <111>. However, this effect is gradually lessened as the strain rate increases. Inversely, in the final pass of the 9-passes set, the flow stress, Vickers hardness and Young’s modulus decrease, while the breaking strain increases. It is evident that the copper develops dynamic recovery and recrystallization due to a less intense <111>.
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Chen-YuYang and 楊鎮宇. "Fabrication and Application of Copper Micro-Nano Wires by Electrochemical Deposition." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/45124110604607507132.
Full textAbstract:
碩士<br>國立成功大學<br>奈米科技暨微系統工程研究所<br>100<br>In this study, we utilized both direct current (DC) and pulse electroforming modes to deposit copper micro-nano wires by anodic aluminum oxide (AAO) template electrochemical deposition method. The variation of morphology and crystallographic structure of copper micro-nano wires between modulated parameters such as voltage, temperature, pore size and duty cycle were investigated. And we also measured the field emission characteristic of copper nanowires.
In the experiment process, the structure of copper micro-nano wires was investigated by scanning electron microscopy (SEM). The crystallographic structure of copper nanowires was characterized by grazing incidence X-ray diffraction (GIXRD). The field emission characteristic of copper nanowires was measured by field emission measurement system.
At direct current electroforming mode, the length of copper microwires at 1, 2, 3 V was 36.23, 49.54, 55.12 μm . The length of copper nanowires at 1, 2, 3 V was 28.45±4.28, 1.01±0.21, 0.66±0.16 μm. The experimental result showed that the growth of copper microwires increased with increasing voltage. The good result of copper nanowires was at 1 V. At the pulse electroforming mode, the length of copper microwires at 1, 2, 3 V was 34.38, 40.48, 49.84 μm. The length of copper nanowires at 1, 2, 3 V was 25.16±2.81, 31.64±4.29, 22.75±4.33 μm. The experimental result showed that the growth of copper microwires increased with increasing voltage. The good result of copper nanowires was at 2 V. At the measurement of field emission characteristic, the sample at template pore size 20 nm, voltage 1 V, duty cycle 50%, temperature 25 ℃ has low turn-on voltage. The copper nanostructure was expected to apply in probes, emitters and interconnects.
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Lin, Hung-Sheng, and 林弘昇. "Influential Factors and Forecasting Models of Enamelled Copper Wires Sales in Taiwan." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/4v2qzv.
Full textAbstract:
碩士<br>國立臺灣海洋大學<br>航運管理學系<br>106<br>This study discuss the influential factors of enamelled copper wires sales in Taiwan and be the base to forecast. First of all to differentiate influential factors from cost factors including copper price & rate and demand factors including asales numbers of electrical & electronic products. Use ADF test, Multiple Regression, Stepwise Regression and Co-integration analysis to observe the relationship of all factors. According to the result of multiple regression and stepwise regression, copper price changing ratio, sales numbers of motor, sales numbers of compressor and sales numbers changing ratio of pump are the more obvious influence factors.
Otherwise, this study also use Johansen co-integration test to make sure factors have long-term equilibrium relationship. Sales number of enamelled copper wires will be influenced by it’s 1st to 3rd and others 1st to 2nd lagging period condition. This study make a VECM model base on the result of co-integration test and verify with the real numerical value. The result shows the error correction percentage being between -5.12%~19.28% and the effect is outstanding.
This study expects to offer some information to make enamelled copper wires company check and adjusted operating strategy to reach the golf of minimum risk and maximum profit.
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Chen, Chen-Ni, and 陳貞霓. "Constructions of Controllable Nanostructure Silver Wires and Microstructure Copper Oxide Donuts by a Surface-Formation Technique." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/9j7u9g.
Full textAbstract:
碩士<br>國立中山大學<br>化學系研究所<br>97<br>In the past few years, the synthesis and fabrication of inorganic nanostructures
with manipulated morphology and size have attracted considerable attention due to
their fundamental importance and potential wide-ranging applications.
Silver nanowires are particularly interesting to study because bulk silver has
the highest electric conductivity among all metals. A number of chemical
approaches have been explored to synthesize 1D silver nanowires.
We demonstrate a simple method to synthesize silver wires by thermal
reduction of aqueous AgNO3 droplet with catalytic anatase TiO2 nanoparticles
which were spin-coated on ITO or glass.
Our simple method can be also applied to generate CuO with donut-shaped
microstructure by using ITO conducting glass as matrix. We have found that the
size and reproducibility are well-controllable. A single phase of CuO donut-shaped
microstructure with outer diameters ranging from ∼ 13 to 17 μm and inner
diameters ranging from ∼ 1.4 to 3.3 μm was obtained. The composition of CuO
microdonut was confirmed by thin-film XRD and XPS analyses.
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Wang, Yuan-Tin, and 王元亭. "A Study of Weibull Analysis on Ultimate Tensile Strength of Fine Copper Wires after EFO Process." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/51307629434372070783.
Full textAbstract:
碩士<br>國立成功大學<br>材料科學及工程學系碩博士班<br>93<br>The advantages of copper wire for wire bonding are lower cost, higher strength and electrical conductivity in comparison with gold wire. Oxidation and insufficient ductility of copper wire resulted in low reliability in the copper wire bonding process, and fracture during wire bonding process is also a factor that reduces reliability. In this study, copper wires (ψ=25μm) of different annealing temperature (150~250℃, hold 1hr) had been melted into a ball by the EFO (Electric Flame Off) process and discussed both the mechanism properties and microstructure with wires and FAB (Free Air Ball). Then the UTS of the wires after EFO process had been discussed by reliability analysis.
As results as the experiments, fully annealed wires could be obtained as annealing temperature was above 200℃. The elongated grains transformed into equiaxed grains due to recrystallization above 200℃, and the tensile data showed lower strength and higher elongation. The microstructure of copper wire FABs revealed columnar grains. The melting of wire tail resulted in a temperature gradient and caused the variation in properties over the region called the heat-affected zone (HAZ). The HAZ showed the lower hardness and UTS due to the recrystallization and growth of new grains. This result made the fracture occurred in HAZ in tensile test and also caused the distribution of the tensile data showed a larger range.
As results as the Weibull analysis, the Weibull modulus under all annealing conditions were wear-out failure mode. UTS of fully annealed wires after EFO process had better reliability than as-drawn wires. And 200℃ was the best condition of annealing.
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Elshewy, Ahmed M. "Efficient C-O and C-N bond forming cross-coupling reactions catalyzed by core-shell structured Cu/Cu2O nanowires." Thesis, 2013. http://hdl.handle.net/10754/306734.
Full textAbstract:
Oxygen and Nitrogen containing compounds are of utmost importance due to their interesting and diverse biological activities. The construction of the C-O and C–N bonds is of significance as it opens avenues for the introduction of ether and amine linkages in organic molecules. Despite significant advancements in this field, the construction of C-O and C–N bonds is still a major challenge for organic chemists, due to the involvement of harsh reaction conditions or the use of expensive catalysts or ligands in many cases. Thus, it is a challenge to develop alternative, milder, cheaper and more reproducible methodologies for the construction of these types of bonds. Herein, we introduce a new efficient ligand free catalytic system for C-O and C-N bond formation reactions.
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Yu-HaoSu and 蘇昱豪. "Microstructures and Electric Flame-Off (EFO) Mechanism of Fine Palladium Coated Copper Wires (PCC) with Thermal Diffusion." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/39510401254917409927.
Full textAbstract:
碩士<br>國立成功大學<br>材料科學及工程學系<br>102<br>In this study, the annealed effect (at 400 ℃~500 ℃ for 30 min) on the tensile mechanical properties and hardness of thin palladium coated copper wires (PCC) Φ =18μm (0.7mil) were investigated. The microstructural characteristics and the mechanical properties before and after an electric flame-off (EFO) were also studied. Results indicated that with annealing temperatures of more than 450 ℃, the wires possessed a fully annealed structure, the tensile strength and the elongation decreased. Through Pd atoms diffusion and equiaxed grains formed in the matrix structure, the PCC wires became the palladium-net wires (PNW). The microstructures of the free air ball (FAB) of the various wires after EFO contained the column-like grains. The column-like grains grew from the heat-affected zone (HAZ) to the Cu ball. From tensile properties, hardness and electrical properties analysis, the 450℃ annealed wires in the neck zones showed the higher reliability than PCC, and retained advantages of PCC, which contained good bondability and IMCs inhibited ability.
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Javvaji, Brahmanandam. "Plasmon Phonon Coupled Dynamics of Nanocrystalline Structures." Thesis, 2018. http://etd.iisc.ac.in/handle/2005/4185.
Full textAbstract:
This thesis is an attempt to understand the characteristics and responses of plasmon phonon coupled dynamics in nanocrystalline structures. An energy based Lagrangian formulation is developed with fundamental field quantities like displacement, charge, electric and magnetic field as variables. Governing differential equations of motion are derived from variational calculus. A new computational framework is implemented to solve for system degrees of freedom, which involve energy and force exchanges between atomic and continuum representation of the system. The developed simulation framework is employed to investigate the phonon and plasmon characteristics for nanocrystalline copper thin films and carbon nanotubes under decoupled scheme. Several fundamental properties are estimated which are found in agreement with experimental and first principle calculations. The simulation framework is applied to analyse the coupling behaviour in a nanocrystalline copper, free standing structurally engineered graphene, pure carbon nanotubes, macromolecular carbon nanotube composite structure, engineered graphene on a silicon substrate and zinc oxide on a zinc substrate. Intense coupled modes are identified using these material models to demonstrate the usefulness of the developed framework and simulation results. The one-dimensional ultrathin copper nanowire has shown the existence of optical phonon modes in copper. Three different plasmon extinction peaks are observed for nanowire. The coupling between the plasmons and optical phonons is reflected in the form of splitting, screening and intensity rise in the phonon density of states. Device configuration with nanowire mounted on a substrate shows a strong excitation of surface plasmon and the phonon oscillations. The charge localization near the defect induces a secondary plasmon excitation. The repetitive electromagnetic irradiation heats up the graphene lattice and achieved a complete screening optical phonons. Uncontrolled heating initiated a lattice failure in graphene with hole defect. A good control on transport of thermal energy is achieved with the help of graphene boundary engineering. The coupled analysis for a single walled carbon nanotube is estimated under controlled temperature at different stages of mechanical elongation. A step wise decay in the plasmon energy is observed with increased in the lattice strain. The local plasmon induced electric fields modulate the phonon intensity and mode switching in strained nanotubes. Macro-molecule involved nanotube binding and the coupled characterstics are analyzed. The combination of zinc oxide nanowire with zinc substrate shows a decrease in the plasmon energy due to the chemical bonding between them. The experimental equivalent growth process is modeled using atomic interaction potentials. The nucleation of zinc oxide from the zinc substrate was confirmed with the bond legth, bond angle and charge computations. The thermodynamic stability of graphene on silicon substrate is investigated through the variation of bond energy and bond density with graphene orientation. A global minimum is found in middle of armchair to zigzag configurations. The silicon-graphene shows two extinction peaks ans strong difference in the plasmon induced coupled phonon mode of vibration. The developed theoretical model and its numerical implementation are useful to get a higher level understanding of dynamical behaviors of various nanoscale devices.
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Sai, T. Phanindra. "Synthesis And Electronic Properties Of Nanowires Of Charge Transfer Complexes." Thesis, 2010. https://etd.iisc.ac.in/handle/2005/1275.
Full textAbstract:
In case of charge-transfer complex of TTF:TCNQ lot of work had previously been done on single crystals and thin films to study various interesting properties including phase transitions which were attributed to Peierls instability. But as seen from the review of molecular wires it is clear that apart from synthesis of TTF:TCNQ in molecular wire form, not much was known about the behavior of these wires at low temperatures. There were some open questions listed below, which we tried to address in the thesis
Can nanowires of TTF:TCNQ be grown across prefabricated electrodes which are separated by gaps < 1 μm.
Can the nanowires grown in such smaller gaps, show Peierls transition, which is the signature of quasi one dimensional conduction. As the size and length of the grown wires are small it was expected that they will have less staking disorder as compared to the thin films.
What will be conduction mechanism at low temperatures in such single/few nanowire samples.
If the nanowires show Peierls transition and CDW formation at low temperatures, can nonlinear conduction be seen due to motion of CDW, if so how well do they compare with the reported results for TTF:TCNQ single crystals.
In case of Cu:TCNQ it can be noted from the above review that even though much advances have been made on synthesizing good quality Cu:TCNQ films and incorporating them in novel device structures, there has been much controversy regarding conduction mechanism. There were many conflicting results in literature regarding switching in these devices. In this thesis work we wanted to address the feasibility of switching in Cu:TCNQ under reduced size of top electrodes and also address few other issues like
To grow Cu:TCNQ nanowires by using vapor phase evaporation method
Can resistive switching be induced in Cu:TCNQ by using a local probe STM tip (Pt-Rh) operated in high vacuum.
Since the measurement will be done in high vacuum what will be the effect of environment (absence of oxygen, water vapor) on reproducibility of resistive switching.
Will localized switching depend on the top electrode material. This has been probed by coating different metals on the C-AFM tip and using them as top electrode in conducting mode.
With what contact force will we get reproducible resistive switching.
Can a device structure be made with an array of top electrode in the form of metal dots (< 10 μm) and study switching using C-AFM.
This thesis is divided into seven main chapters and two appendix chapters, which are listed below:
In the present chapter 1, a detailed overview and literature survey of charge-transfer complexes TTF:TCNQ and Cu:TCNQ which were relevant to our present study was presented. This was followed by our motivation in undertaking the present work.
In chapter 2 the various experimental techniques developed during the course of the thesis work such as e-beam lithography, design of the vacuum chamber for deposition of organic molecules, design of ultra high vacuum scanning tunneling microscope (UHV-STM chamber along with the STM head, modification of conducting AFM for obtaining the switching data have been described.
In chapter 3 we describe the preparation of TTF:TCNQ molecular wires across prefabricated electrodes and different measurements done on the samples. In particular the observation Peierls transition in the grown nanowires of TTF:TCNQ and the nonlinear conduction mechanism involved at low temperatures will be discussed in detail.
In chapter 4 we describe the preparation of Cu:TCNQ nanowires on Cu substrate using vapor phase technique. Resistive switching measurements done on the Cu:TCNQ nanowires in high vacuum with Pt-Rh tip as top electrode will be discussed in detail.
In chapter 5 we describe the resistive switching measurements performed on Cu:TCNQ nanowires with different metal coated C-AFM tips as well as FIB deposited platinum dots as top electrodes.
In chapter 6 we make a few comments about possible switching mechanism involved, when STM tip, C-AFM induced as well as platinum coated dots were used as top electrodes.
In chapter 7 we conclude this thesis by summarizing the main results. Also we point out the scope for future work that can be based upon the results presented in this work.
In Appendix A a brief review of self assembled monolayer (SAM) of alkane thiols is presented followed by details about experiments done for insitu study of growth of SAMs of decanethiol and octadecanethiol on silver substrates using ellipsometry and force-displacement spectroscopy.
In Appendix B a brief description of work done to grow isolated nanowires of Cu:TCNQ, between two metal electrodes in planar geometry and in anodic alumina membranes is given.
29
Sai, T. Phanindra. "Synthesis And Electronic Properties Of Nanowires Of Charge Transfer Complexes." Thesis, 2010. http://etd.iisc.ernet.in/handle/2005/1275.
Full textAbstract:
In case of charge-transfer complex of TTF:TCNQ lot of work had previously been done on single crystals and thin films to study various interesting properties including phase transitions which were attributed to Peierls instability. But as seen from the review of molecular wires it is clear that apart from synthesis of TTF:TCNQ in molecular wire form, not much was known about the behavior of these wires at low temperatures. There were some open questions listed below, which we tried to address in the thesis
Can nanowires of TTF:TCNQ be grown across prefabricated electrodes which are separated by gaps < 1 μm.
Can the nanowires grown in such smaller gaps, show Peierls transition, which is the signature of quasi one dimensional conduction. As the size and length of the grown wires are small it was expected that they will have less staking disorder as compared to the thin films.
What will be conduction mechanism at low temperatures in such single/few nanowire samples.
If the nanowires show Peierls transition and CDW formation at low temperatures, can nonlinear conduction be seen due to motion of CDW, if so how well do they compare with the reported results for TTF:TCNQ single crystals.
In case of Cu:TCNQ it can be noted from the above review that even though much advances have been made on synthesizing good quality Cu:TCNQ films and incorporating them in novel device structures, there has been much controversy regarding conduction mechanism. There were many conflicting results in literature regarding switching in these devices. In this thesis work we wanted to address the feasibility of switching in Cu:TCNQ under reduced size of top electrodes and also address few other issues like
To grow Cu:TCNQ nanowires by using vapor phase evaporation method
Can resistive switching be induced in Cu:TCNQ by using a local probe STM tip (Pt-Rh) operated in high vacuum.
Since the measurement will be done in high vacuum what will be the effect of environment (absence of oxygen, water vapor) on reproducibility of resistive switching.
Will localized switching depend on the top electrode material. This has been probed by coating different metals on the C-AFM tip and using them as top electrode in conducting mode.
With what contact force will we get reproducible resistive switching.
Can a device structure be made with an array of top electrode in the form of metal dots (< 10 μm) and study switching using C-AFM.
This thesis is divided into seven main chapters and two appendix chapters, which are listed below:
In the present chapter 1, a detailed overview and literature survey of charge-transfer complexes TTF:TCNQ and Cu:TCNQ which were relevant to our present study was presented. This was followed by our motivation in undertaking the present work.
In chapter 2 the various experimental techniques developed during the course of the thesis work such as e-beam lithography, design of the vacuum chamber for deposition of organic molecules, design of ultra high vacuum scanning tunneling microscope (UHV-STM chamber along with the STM head, modification of conducting AFM for obtaining the switching data have been described.
In chapter 3 we describe the preparation of TTF:TCNQ molecular wires across prefabricated electrodes and different measurements done on the samples. In particular the observation Peierls transition in the grown nanowires of TTF:TCNQ and the nonlinear conduction mechanism involved at low temperatures will be discussed in detail.
In chapter 4 we describe the preparation of Cu:TCNQ nanowires on Cu substrate using vapor phase technique. Resistive switching measurements done on the Cu:TCNQ nanowires in high vacuum with Pt-Rh tip as top electrode will be discussed in detail.
In chapter 5 we describe the resistive switching measurements performed on Cu:TCNQ nanowires with different metal coated C-AFM tips as well as FIB deposited platinum dots as top electrodes.
In chapter 6 we make a few comments about possible switching mechanism involved, when STM tip, C-AFM induced as well as platinum coated dots were used as top electrodes.
In chapter 7 we conclude this thesis by summarizing the main results. Also we point out the scope for future work that can be based upon the results presented in this work.
In Appendix A a brief review of self assembled monolayer (SAM) of alkane thiols is presented followed by details about experiments done for insitu study of growth of SAMs of decanethiol and octadecanethiol on silver substrates using ellipsometry and force-displacement spectroscopy.
In Appendix B a brief description of work done to grow isolated nanowires of Cu:TCNQ, between two metal electrodes in planar geometry and in anodic alumina membranes is given.
30
Tseng, Tzu-Hung, and 曾子航. "The Investigation of Reliability Check for Palladium Copper Wire and Copper Wire." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/a9jjfm.
Full textAbstract:
碩士<br>國立高雄大學<br>電機工程學系--先進電子構裝技術產業研發碩士專班<br>105<br>With the high price of gold, gold-based packaging costs continue to increase, many packaging manufacturers in order to reduce costs have developed new wire materials to rEPMAce the gold line, and strive to not affect the performance of products in the case of cost-effective selection High welding wire materials to reduce costs to metal copper as raw materials made of wire is a very good option, but because of the difference between the physical properties of gold and copper itself, in the welding line, and then understand the different The characteristics of welding wire materials for the packaging business is still a great practical significance.
First for the palladium copper wire, in different current settings, and IC to understand the reliability of the packaging industry and the failure of the problem.
In this paper, a series of experiments on the copper and palladium copper wire related to the nature of the study, through the tension and the way to measure the way to compare the two kinds of welding line in the oxidation of the storage capacity, and then through the high temperature storage experiment to analyze Reliability and failure reasons of welding wire in cruel experimental conditions.
31
Yen, Chu-Chiao, and 顏楚喬. "Destructive Analysis in Copper Wire Devices." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/63960678850146613808.
Full textAbstract:
碩士<br>國立高雄應用科技大學<br>電子工程系<br>97<br>Accompany the price of gold raised; package technique will be used copper wire instead gold wire in the interconnection of IC devices little by little. In package process, when de-capsulation and crater test of failure analysis were performed on the copper wire devices, we found copper wire was very worse than gold wire on acid etching process. Due to copper wire corrosion is very serious and it will be caused the misjudgment after destructive analysis. Hence, for workability and reliability concern, we can’t provide the correctly analysis data to support process improvement. Build up the optimize parameter to perform destructive analysis on the copper wire device and support process engineer to improve process capability and failure analysis.
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Hung, Chong-Wei, and 洪崇偉. "The Study for Reliability of Wire-bonding Process by Copper Wire." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/3qe2x3.
Full textAbstract:
碩士<br>國立高雄大學<br>電機工程學系碩士班<br>102<br>As technical developments progressed, semi-conductor packaging is now heading toward slender, high-density and high capillary count directions. At present, domestic package techniques are BGA(Ball Grid Array), QFP(Plastic Quad Flat Package), SOP(Small Out-Line Package), PLCC (Plastic Leaded Chip Carrier) and PDIP(PDIP Plastic Dual In-Line Package )based package techniques. Since BGA package technique generally involves solder ball arrayed at the base of chip base, solder ball replaces traditional lead frame surrounded by pins. One advantage of this type of package technique is that the No. of pins may increase with same size and area while the package area and weight are only half the QFP. It also has good electric and heat dissipation properties as well as package area reduction feature. Its demand and growth rate greatly exceed other package methods. Currently, most, information home electronic appliances and 3C products have adopted BGA package technique.
This study aims is to pass reliability of wire-bonding process by copper wire. Based on the 3 quality characteristics of process intended for discussion, wire pull, ball shear , Internal Metal Coverage of the quality characteristics are obtained. Then, by use of Orthogonal array L9 and Reliability Temperature cycle Test, analysis why Internal Metal Coverage is the major factor to influence Open Test after Reliability . In addition, in order to pass reliability test, how to do good Internal Metal Coverage sample. The feasibility of this study method tested is further verified.
33
Chang, He-Chieh, and 張賀傑. "Mechanical Properties of Oxygen-Free Copper Wire the Fine Wire Drawing." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/99916320895419538143.
Full textAbstract:
碩士<br>國立宜蘭大學<br>機械與機電工程學系<br>101<br>The study for mechanical properties and plastic behavior when OFC(Oxygen-Free Copper) wire be go through different size of diamond dies,than record it what effect on skin pass.
The original size of OFC isφ1.0mm, passing through 13 pass to 0.1mm.Than it,which after annealed at 350℃,be passed through 10 pass to φ0.03mm.In accordance with CNS2112,the original gauge length of tensile specimen is 9A. In accordance with CNS2111,the Electrical Material Testing Machine be set up for adding load should be linearly.In accordance with CNS9504, by Optical Microscopy metallographic analysis that longitudinal section of wire be detected.
The results saying,first,the one dies passes drawing to discover the relationship with drawing loading,reduce rate and stress in wire drawing. Second,from tensile test,we can derived the formula about coefficient of friction and die surface pressure when passing the dies.
In the study, The data were obtained from experiments will reference for fine wire drawing process.
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CHENG, CHUNG-HAO, and 鄭中豪. "Development of Automatic Copper Wire Elongation System." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/br2syh.
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碩士<br>國立勤益科技大學<br>電子工程系<br>107<br>Copper wire is currently a most widely used conductive material for transmitting various signals. Its size can be produced as small as 0.01mm, particularly in medical health equipment. Although most of the wire elongation process has been atomized, it still requires human to thread the wire through tens of die molds in advance, usually taking tens of minutes. To resolve this problem, this paper develops an automatic mechanical control system for wire elongation. The proposed hardware system mainly contain three pneumatic claws that can replace the human hands operation are designed in the proposed system. The first claw is used to clamp the wire. The second claw fixed in the rotating mechanism is to draw the heated wire. The third claw is used to move the wire going through the die molds. The wire drawing power is generated from the gear connection controlled by the serer motor. The control software is developed by PLC programming. The experimental results confirm that the proposed can work efficiently in terms of robust and rapid performance.
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HendrikHartono and 謝康明. "Growth of Copper Oxide Nanowires on a Copper Wire via Thermal Oxidation." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/51808484336559486349.
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碩士<br>國立成功大學<br>機械工程學系<br>104<br>In this study, the influences of temperature, duration and oxygen concentration on the growth of copper oxide nanowires on the surface of a copper wire through thermal oxidation method were studied. Scanning electron microscope (SEM) images were taken to reveal the density, diameter and length of the nanowires. The weight gain during the oxidation process were quantified with thermogravimetric analysis. It was found that nanowire growth on the copper wire surface was relatively slow for temperatures below 500 oC, and the oxidation rate increased monolithically above this threshold temperature. SEM images showed that the CuO nanowires were longer at high temperatures, however, the density of the nanowires was lower at 600 oC comparing to 400 oC and 500 oC. Oxidation duration, on the other hand, did not significantly affect the length of nanowire, but the distribution of the nanowire density. There were no significant changes on nanowires geometry using different oxygen concentration. Weight gain of Cu wire was obtained from thermogravimetric analysis and obeys parabolic oxidation rate law. The Arrhenius plots are able to be roughly classified into three regions: high temperature region (550 oC to 700 oC), intermediate temperature region (400 oC to 550 oC), and low temperature region (325 oC to 400 oC).
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Chien, Jihhsin, and 簡日新. "Interfacial Bondability Study on Copper-Aluminum Alloy during Copper Wire Bonding Process." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/91640557528570455438.
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碩士<br>義守大學<br>機械與自動化工程學系<br>101<br>The ultra-fin copper wire will become a free air ball after electronic flame-off. During thermalsonic ball bonding, copper and aluminum will stick together by intermetallic compound. There are CuAl、CuAl2、Cu9Al4 and intermetallic compound will affect the reliability in the bonding process. In this study we using the molecular dynamics simulation to study the IMC’s tensile test in nanoscale then we can get the mechanical property that can make us to know the IMC’s young’s modulus then we use curve fitting to fit out young’s modulus.
At first, we use EDX to detect the substance that grow on the die. Secondary, make the IMC experiments for nanoindentation test and analysis the young’s modulus.In the third, we use molecular dynamic simulation to analysis the glide plane during the tensile test we calculate the young’s modulus to compare simulation and experiments.
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Engbrecht, Edward Raymond Ekerdt John G. "Fundamental studies of copper diffusion barriers." 2004. http://repositories.lib.utexas.edu/bitstream/handle/2152/1958/engbrechter042.pdf.
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WANG, ZI-WEI, and 王子維. "Process Design and Experiment of Copper Wire Drawing." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/kakfsu.
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碩士<br>國立高雄應用科技大學<br>模具工程系<br>104<br>Copper with excellent electrical and thermal conductivities was commonly used in cables, coils and other electronic products. Due to poor control of wire drawing process and it mechanical properties, fracture often happens in the drawn wire. Therefore, the understanding of the mechanical properties of the drawn wire is important for the process design.
This study used finite element simulation and experiment to investigate the copper wire drawing process in order to provide the designs of process parameters and die geometry, and to develop an analysis technology of metallograph. By using simulation and Taguchi Method, the study investigated the influences of drawing parameter on the strain distribution and load in the copper drawing process. Some experiments were also conducted in order to verify the predicted results. Moreover, the study developed a numerical program based on the functions provided by commercial software MATLAB to analyze the digital image of metallograph. The program was able to estimate the quantity, size and area of grains, and the boundaries of grains which can be the references for process design.
The results show that the use of the simulation and Taguchi Method to design the process conditions can reduce the difference in strain distribution and load. The distribution of the tensile strength across drawn wire section was similar to predicted one in the first and second stages. However, the distribution was reverse after the third stage of the drawing process. The highest hardness occurred in the outer region of the drawn copper. Moreover, the dies designed by Taguchi Method resulted in the lower hardness than those designed by practical rules. Furthermore, the developed program for metallograph analysis was able to accurately predict the quantity and area of grains and the distribution of grain sizes, and to successfully obtain the information on the boundary grains.
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You, Chung-Pao, and 游忠堡. "The Study of Ultrasonic aided Copper Wire Drawing." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/t5yny4.
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碩士<br>國立虎尾科技大學<br>創意工程與精密科技研究所<br>98<br>This study analyzed and discussed the ultrasonic vibration-aided copper wire drawing processing method. The principle of ultrasonic-aided drawing processing is to make the wire drawing die or the drawn wire generates ultrasonic vibration in general wire drawing process. It is a processing technology incorporating ultrasonic vibration energy in the course of wire drawing. This processing technology can reduce the drawing force, improve the surface quality and increase the working efficiency. It is especially effective for the drawing of wire of difficult-to-machine material.
The main purpose of this study is to discuss the effect of ultrasonic vibration on wire drawing process. Therefore, it developed an ultrasonic wire drawing mechanism, and discussed the influence of ultrasonic shake frequency on drawing force change, as well as that of drawing speed and vibration intensity on drawing force in the ultrasonic-aided wire drawing process by testing sonic drawing head in radial ultrasonic vibration mode. This study also used the finite element method to simulate and validate whether the resonance frequency of sonic welding head meets the required condition. Designers can simulate the processing first, and then use the Taguchi Method to obtain the control factors of this machine. The adjusted factors are for experimental validation, and the analysis of variance of the Taguchi Method is applied to find out the relative contribution of experimental factors, in order to provide a reference for the development of the primary system of machine.
This study also used an optical microscope and a tensile testing machine to discuss the microcosmic influence of ultrasonic vibration on brass wire under different wire drawing parameter conditions. An electron microscope was used for metallurgical analysis of wire, and the tensile test of wire was carried out.
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YANG, CHU-WEN, and 楊筑雯. "The Investigation of Relationship between Wire Bonding Process Parameter and Reliability of Copper Wire." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/2687t5.
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碩士<br>國立高雄大學<br>電機工程學系--先進電子構裝技術產業研發碩士專班<br>105<br>The study focuses on the bonding parameters and its relationship to the product reliability of copper wires in IC packaging. In general, palladium can be used to protect copper balls from attack of chlorine ions that are inherent to molding compounds which will avoid the reliability and field failures on humidity environment. In this experiment, the best parameters were found for EFO Current、EFO Gap、and Forming Gas rate to produce the best “post bond palladium coating distribution” on the copper ball. A reliability test was used to verify the effectiveness and found to have no failure.
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Chen, Yi-feng, and 陳儀峰. "The Material Characteristics of Gold Wire/Copper Wire and Dynamic Response on Bonding Process." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/71578047131210425689.
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碩士<br>義守大學<br>機械與自動化工程學系碩士班<br>97<br>Wirebonding assembly has been widely used in the semiconductor package for the past two decades. The welding wire bonding technology is based on electricity as a link and as the transmission of signals. Material strength of copper wire is higher than gold wire. Higher strength copper brings about Al pad shovel (excessive plastic deformation) around the ball bond when wirebonding process is conducted. Reliability in Copper wire bonding process includes ball lifted, peeling and cracking beneath bond pad. Manufacturing process also required special attention to prevent oxidation.
This research involves in four parts: In the first, Young’s modulus on ultra thin surface is experimentally determined by nano indentation instrument. Secondary, Atomic Force Microscopy (AFM) is applied to measure interfacial frictional coefficient and the surface roughness. In the third, corrosion experiments for gold wire and copper wire are performed and observed for metallographic. The last is that numerical prediction for wirebonding process is conducted based on commercial finite element software of ANSYS/LS-DYNA.
The surface tensile mechanical properties for ultra thin gold wire, copper wire and Al pad are obtained through nonointentation technology. Atomic Force Microscopy (AFM) is applied to measure the micro surface coefficient of frictional force. The measured interfacial coefficient of frictional force between silicon-based cantilever beam and specimen material need to be correlated on thrust force and normal force. Surface roughness on Al pad is specially focused because uneven surface will affect the wire bonding process. Therefore, the interfacial frictional mechanism on Al pad needed to be carefully analyzed.
The accurate experimental material data should be reflected as input for the precise finite element analysis. Numerical model based on explicit time integration scheme software ANSYS/LS-DYNA is developed to predict the first bond (ball bond) of wirebonding process. The impact effects on structure stressed area during wire bonding process are investigated and the shovel (large plastic deformation) of Al pad was observed during transient ultrasonic vibration stage. It is noted that the material of bond pad should be Al-Cu pad instead of pure Al pad. Special emphasizes are focused on the underlay via layouts and the optimal design of microstructure beneath the bond pad. A series of comprehensive parametric studies were conducted in this research.
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Engbrecht, Edward Raymond. "Fundamental studies of copper diffusion barriers." Thesis, 2004. http://hdl.handle.net/2152/1958.
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Lin, Min-Hui, and 林敏輝. "A Study of Fine Copper Wire for SOC Packaging." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/13531091686122326943.
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碩士<br>明新科技大學<br>系統晶片與嵌入式系統產業研發研究所<br>98<br>With the progress of science and technology industry, not off, consumer demands for electronic products, in order to meet consumer demand, IC design companies to develop a variety of products to meet market trends, multi-system towards integrated chip (SOC ; System on a Chip) development, so that the product may have more multi-functional external and has a superior performance.
In the current IC Packaging domain, process most of the use of gold wire connected chips and substrates, but gold prices have been skyrocketing in recent years, resulting in the cost of increasing on packaging. It can reduce the cost about 10 ~ 20% to replac the gold wire into copper wire.
This study is intended for 20 um palladium plated copper wire with mature in the mass production of 20 um gold wire of LQFP ( Low Profile Quad Flat Package ) 128 pin package, through the three stages of the experiments and comparisons, to identify key parameter combinations by BIT ( Bonding Integration Testing ), MIT (Molding Integrated Test) and reliability testing to analysis the quality characteristics of palladium plated copper wire.
Learned from the experimental results, the key parameters setting can be assured of the best in the quality characteristics. At the same time on workability do more than on, found in more longer process time, production control more stringent, but yield and quality is same to gold, costs can be reduced about 10 ~ 20%.
Different from the past validation rules, the copper wire problems with easy-to-oxidation, and hardness is too high, easily damage to the pad, and other considerations. Packages should be qualified by each product material structure, especially in the advanced wafer technology.
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Zhang, Li-Fu, and 張力夫. "The Study of the Mechanical Strength with Copper Wire." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/85788518283267145133.
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碩士<br>國立宜蘭大學<br>機械與機電工程學系碩士班<br>98<br>In the plastic forming process, there are room temperature processes such as general of the sheet or tube forming, machining process, although the temperature changes, but basically are at a certain temperature range to complete. The most typical examples of the other forming in high temperature are forged or extruded shape processing, there are a lot of numerical analysis software both can simulate the machining process and the state, often in high-temperature processing of the simulation process, experience high temperatures mechanical properties of materials is unknown, making the reliability of numerical simulation to lose.
Purpose of this study is pinpointing the high temperature mechanical strength of copper metal to experimental analysis, first copper at room temperature and the set temperature for a constant temperature, then use the tensile testing machine to tensile copper wire in constant speed and recorded drawing force by the load cell, and measure the length and area of material changes have been calculated maximum stress, strength coefficient and strain hardening exponent at room temperature and different temperature, then under different temperature of copper wire, maximum stress, strength coefficient and strain hardening exponent compared to chart. The results of experimental can be clearly seen that the maximum stress and the strength coefficients were decreased as the temperature rises.
This study also provides the map of the temperature and strain hardening exponent and the temperature coefficient with the strain hardening map, also properties the basic material of copper metal for the use of numerical analysis.
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Jang, Hung-Sheng, and 張弘昇. "Bondability Analysis and Reliability Design on Copper Wire Bonding." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/28877948787564001882.
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碩士<br>義守大學<br>機械與自動化工程學系碩士班<br>98<br>The wire bonding process has been widely used in the semiconductor package industry for the past two decades for its easy application and low cost. However, the mechanism of dynamic response for wire bonding process is scarcely reported due to the material data is difficultly to determine. As the price of gold is dramatically increasing in the year of 2009, engineers and researchers have been focused on the replacement material of copper wire.
In order to reduce the cost, we use copper wire in substitution for gold wire.Copper wire has better electrical conductivity and thermal conductivity than gold wire, but copper wire is oxidation easily and material strength is higher than gold wire. It maybe brings aluminum pad squeeze (excessive plastic deformation) because material strength of copper wire is high. This research involves in three parts: the first is we etching copper wire and use SEM to see the grain. Secondary, Atomic Force Microscopy (AFM) is applied to measure interfacial frictional coefficient and the surface roughness, and we take the data into ANSYS to simulate. In the third, numerical prediction for wire bonding process is conducted based on commercial finite element software of ANSYS/LS-DYNA. In this research, we take our attention in aluminum pad squeeze, so we use metallography experiment to understand the grain become big and the material strength is lower. It is noted that the material of bond pad should be Al pad instead pure Al pad. Special emphasizes are focused on the via layouts and the optimal design of microstructure beneath the bond pad. A series of comprehensive parametric studies were conducted in this research.
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Liau, Ming-Tui, and 廖明對. "The Analysis of Heat Effect of Copper Alloy Wire." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/57601387131929067578.
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碩士<br>高苑科技大學<br>機械與自動化工程研究所<br>99<br>This study is aimed at heat effect of copper alloy wire. A series of tests is conducted with different wiring patterns. Taguchi experimental method with ANOVA is used to analyze the significance of the control factors. It is revealed experimentally that the factor D, wiring type, is considerably significant to the heat effect of copper wire. The confidence level of factor D is up to 99.3% by ANOVA. Therefore, for the purpose of safety, the appropriate fuse should be chosen on wiring. The wire with great resistance and high melting point is easily rising the temperature as electrifying. the investigation of temperature response of electrifying copper alloy wire with various connected type and the imperfection of wire. It is revealed experimentally that, for the safety, the best wired is using a proper fuse uncoiling wire and fastening the wire-connecter. The large impedance and high melting point material being substituted for fuse, S-type wire coiled and imperfect wire (some wire cores broken) are avoided to keep off an accident due to the rising temperature as electrifying.
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CHEN, HAUAN-CHU, and 陳宣竹. "System software development for automatic Copper Wire Elongation process." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/k9cu6t.
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碩士<br>國立勤益科技大學<br>電子工程系<br>107<br>Before the industry conducts automatic wire drawing operations, the wires have been manually thinned and passed through the eye molds. However, increasing labor cost is becoming a big challenge in industry. For this reason, design an automation system software, with the wire through the eye mold mechanism, the software design proposed in this paper includes wire extension system, eye mold crossing system, man-machine interface. PLC is used as a core controller that controls pneumatic cylinder and server motor. Human machine interface is also designed for friendly operation. The simulation performance results confirm that the proposed is capable of carrying out an automatic Copper Wire Elongation process effectively.
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Chiu, Sheng Hsuan, and 邱聖軒. "Study on Discharge Coating and Mechanical Properties of Wire EDM by Nickel-coated Copper Wire and Conventional Brass Wire." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/75316151694539495059.
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碩士<br>國立高雄應用科技大學<br>模具工程系<br>104<br>The harder mold material makes it difficult to be cut through traditional machining processes. Therefore, the electrical discharge machining (EDM) or Wire-EDM are often adopted in related industrial processing. However, due to the fact of micro-cracks and pores often appearing under the workpiece surface after EDM processes, it result in the decrease of mechanical properties of the material. At the other hand, It is also common to add nickel metal in steel materials since it can improve the mechanical properties of the raw steel, and it was conjectured that nickel powder may be suitable to fulfill the micro-cracks and pores effectively. In aspect of electroplating for molds, the material of the coating matrix is often nickel, as well as alloy like nickel-cobalt and copper-nickel, etc., which indicating that the nickel is also popular in surface treating. In addition, from EDS analysis of the workpiece surface after Wire-EDM processes, the adhesive phenomenon on wire electrode material is quite evident. Thus, the idea derived from that the electrode material melts on the workpiece and forms a coating layer (or EDM cladding layer) under the high temperature of the intermittent discharging energy from EDM is then hit upon. Therefore, this thesis makes a comparison of using nickel-plated copper wire and regular brass wire in the designed Wire-EDM coating processes, to achieve surface modification through eliminating recast layer and fulfilling the micro-cracks or pores produced by Wire-EDM at one procedure, as well as the improvement of mechanical properties.
The research adopted nickel-plated copper wire form material company of conductors field, and M333 tool steel as workpiece. The goal is focused on the profile and texture of the work surface after processing, the roughness, covered ingredients and anti-abrasion performance are also concerned. The effects of machining parameters such as open-voltage〖 (O〗_V), on-time; or discharging period (T_ON), feed-rate (F) are investigated, respectively. The open-voltage is selected from 85V, 105V, and 125V, respectively. The on-time of discharging is set from 0.1μs to 0.2μs for small energy surface treatment. The pulse off-time is selected from a set of 15μs, 20μs, and 25μs. The fixed setting of feed speed is chosen from one of 0.5mm/min, 1.0 mm/min, and 2.0 mm/min. Alternative current (AC) power generator is used in conducting the experiment of Wire-EDM coating processes. It is found that the relatively optimal processing conditions for surface modification are open-voltage O_V 105V, T_ON 0.1μs, off-time T_OFF 25μs, and under the fixed feed-rate of 0.5mm/min. Under such a combination of operating condition, the most uniformly distributed and abundant alloy layer through Wire-EDM coating, or cladding, was obtained. Comparison on the mechanical properties revealed that the workpiece conducted through brass wire preserved a little stronger anti-bending strength before the yield point, but once going to plastic deformation, the nickel cladding workpiece revealed much higher stress.
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Chou, Yung-Jen, and 周勇任. "0.8 mil Au-Pd coated copper wire parameter optimization in BGA packaging wire bonding process." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/gy4juw.
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碩士<br>國立彰化師範大學<br>機電工程學系<br>107<br>The semiconductor packaging and testing industry is developing principles with improved transmission efficiency, better heat dissipation, increased I/O count, volume miniaturization and lower cost with quality reliability. The improvement of process yield in the characteristics of product development principles is the continuous goal of each test and test factory.
Wire Bonding is a bottleneck process in a ball grid array package (BGA). The parts that directly affect the quality of the work in wire bonding are raw materials (wafer, substrate, metal wire), parts (capillary), and wire bonding parameters. The JMP software's Taguchi experimental design method was used to analyze and obtain the optimal wire bonding parameters. The material was measured by the inter metallic compound, the tool microscope measuring sphere, the wire pull test, the ball shear test and the crater test.
In this study, the total alarm rate of the optimum parameters was reduced from 0.57% to 0.11% compared with the control parameters, and the hourly output increased by 58.74 pcs from 54.50 pcs, and the product yield increased from 99.77% to 99.85%.
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Huang, Guo Lun, and 黃國倫. "Canine temporary contraception with copper wire occluded in vas deferens." Thesis, 1995. http://ndltd.ncl.edu.tw/handle/50790273107483018462.
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