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1
McGivern, Cu-Hullan Tsuyoshi. "Comparing the medium-term effects of exercise or dietary restriction on appetite regulation and compensatory responses." Thesis, Queensland University of Technology, 2011. https://eprints.qut.edu.au/47164/1/Cu-Hullan_McGivern_Thesis.pdf.
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Previous studies have shown that exercise (Ex) interventions create a stronger coupling between energy intake (EI) and energy expenditure (EE) leading to increased homeostasis of the energy-balance (EB) regulatory system compared to a diet intervention where an un-coupling between EI and EE occurs. The benefits of weight loss from Ex and diet interventions greatly depend on compensatory responses. The present study investigated an 8-week medium-term Ex and diet intervention program (Ex intervention comprised of 500kcal EE five days per week over four weeks at 65-75% maximal heart rate, whereas the diet intervention comprised of a 500kcal decrease in EI five days per week over four weeks) and its effects on compensatory responses and appetite regulation among healthy individuals using a between- and within-subjects design. Effects of an acute dietary manipulation on appetite and compensatory behaviours and whether a diet and/or Ex intervention pre-disposes individuals to disturbances in EB homeostasis were tested. Energy intake at an ad libitum lunch test meal after a breakfast high- and low-energy pre-load (the high energy pre-load contained 556kcal and the low energy pre-load contained 239kcal) were measured at the Baseline (Weeks -4 to 0) and Intervention (Weeks 0 to 4) phases in 13 healthy volunteers (three males and ten females; mean age 35 years [sd + 9] and mean BMI 25 kg/m2 [sd + 3.8]) [participants in each group included Ex=7, diet=5 (one female in the diet group dropped out midway), thus, 12 participants completed the study]. At Weeks -4, 0 and 4, visual analogue scales (VAS) were used to assess hunger and satiety and liking and wanting (L&W) for nutrient and taste preferences using a computer-based system (E-Prime v1.1.4). Ad libitum test meal EI was consistently lower after the HE pre-load compared to the LE pre-load. However, this was not consistent during the diet intervention however. A pre-load x group interaction on ad libitum test meal EI revealed that during the intervention phase the Ex group showed an improved sensitivity to detect the energy content between the two pre-loads and improved compensation for the ad libitum test meal whereas the diet group’s ability to differentiate between the two pre-loads decreased and showed poorer compensation (F[1,10]=2.88, p-value not significant). This study supports previous findings of the effect Ex and diet interventions have on appetite and compensatory responses; Ex increases and diet decreases energy balance sensitivity.
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Sommadossi, Silvana Andrea. "Investigation on diffusion soldering in Cu-In-Cu and Cu-In-48Sn-Cu systems." Stuttgart : Max-Planck-Inst. für Metallforschung, 2002. http://deposit.d-nb.de/cgi-bin/dokserv?idn=965684601.
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Uljanionok, Julija. "Cu(I) Kompleksų vaidmuo glicinatinių ir maleatinių Cu(II) kompleksų elektrocheminės redukcijos procesuose." Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2010. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2010~D_20100204_100342-68643.
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Atliktas palyginamasis dviejų kompleksinių sistemų - Cu|Cu(II), glicinas ir Cu|Cu(II), maleino rūgštis - elektrocheminių charakteristikų tyrimas.
Nustatytos maleino rūgšties tirpalų pusiausvyrinės charakteristikos. Kiekybiniam titravimo kreivių aprašymui išvestos lygtys, kuriose įvertinti medžiagų bei krūvių balansai bei atsižvelgta į praskiedimo efektus. Jų taikymas pH-metrinių duomenų analizei davė tokias maleato anijonų protonizacijos konstantų reikšmes: log = 6,05, log = 7,48. Nustatyta, kad tirpaluose su 0,3 M K2SO4 priedu protonizuotų ligando formų stabilumas sumažėja (log = 5,75, log = 7,30).
Cu(II) maleatinių kompleksų stabilumui nustatyti panaudotas spektrofotometrijos metodas ir pasiūlyta duomenų analizės procedūra. Ji remiasi kiekybiniu absorbcijos spektrų aprašymu, taikant lygtis, išplaukiančias iš valdomo harmoninio osciliatoriaus teorijos. Išanalizavus įvairių sudėčių tirpalų absorbcijos maksimumo dydžius, prieita išvados, kad rūgščiose terpėse vyrauja monoligandinis kompleksas, kurio koncentracinė stabilumo konstanta log b1 = 2,2.
Atlikta sistemos Cu|Cu(II), maleino rūgštis pusiausvyrų termodinaminė analizė. Nustatyta, kad esant metalinio vario ir tirpalų sąlyčiui, sistemoje galimi gilūs virsmai, kurių metu iki 90 % Cu(II) transformuojasi į Cu(I). Teorines išvadas patvirtina eksperimentiniai duomenys, gauti spektrofotometrijos ir elektrocheminės kvarco kristalo mikrogravimetrijos metodais. Įvertinti Cu korozijos bei fazinių Cu2O sluoksnių susidarymo... [toliau žr. visą tekstą]A comparative investigation of electrochemical characteristics of two complex systems, viz. Cu|Cu(II), glycine and Cu|Cu(II), maleic acid, was carried out. The equations were obtained for quantitative description of pH-metric and spectrophotometric data, which were used for determination of equilibrium characteristics in Cu(II)-maleic acid solutions. Thermodynamic analysis shows that deep changes are possible in this system resulting in 90 % transform of Cu(II) into Cu(I). The rates of Cu corrosion and Cu2O formation are estimated to be of the same order (nmol cm-2 s-1). Regularities of formal electrochemical kinetics, which account for the mass transport of chemically interacting particles and for step-wise charge transfer process, are suitable for interpretation of voltammetric data of the Cu|Cu(II), glycine system. Kinetic parameters Cu(II) glycinate complex depend on the nature of the supporting electrolyte: the exchange current density decreases and the cathodic charge transfer coefficient increases in the sequence: Li+ - Na+ - K+ - Cs+. To enhance the Cu(I) generation in maleic acid system, the pre-electrolysis procedure was applied. It was found that its effect depends on solution pH. Applied theoretical model describes satisfactorily the steady-state voltammetric characteristics of Cu|Cu(II), maleic acid system, but some contradictory results were obtained in the case of time-dependent processes. Theoretical and experimental problems to be solved are discussed.
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Uljanionok, Julija. "Role of Cu(I) complexes in the electrochemical reduction of glycinate and maleate Cu(II) complexes." Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2010. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2010~D_20100204_100357-81350.
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A comparative investigation of electrochemical characteristics of two complex systems, viz. Cu|Cu(II), glycine and Cu|Cu(II), maleic acid, was carried out. The equations were obtained for quantitative description of pH-metric and spectrophotometric data, which were used for determination of equilibrium characteristics in Cu(II)-maleic acid solutions. Thermodynamic analysis shows that deep changes are possible in this system resulting in 90 % transform of Cu(II) into Cu(I). The rates of Cu corrosion and Cu2O formation are estimated to be of the same order (nmol cm-2 s-1). Regularities of formal electrochemical kinetics, which account for the mass transport of chemically interacting particles and for step-wise charge transfer process, are suitable for interpretation of voltammetric data of the Cu|Cu(II), glycine system. Kinetic parameters Cu(II) glycinate complex depend on the nature of the supporting electrolyte: the exchange current density decreases and the cathodic charge transfer coefficient increases in the sequence: Li+ - Na+ - K+ - Cs+. To enhance the Cu(I) generation in maleic acid system, the pre-electrolysis procedure was applied. It was found that its effect depends on solution pH. Applied theoretical model describes satisfactorily the steady-state voltammetric characteristics of Cu|Cu(II), maleic acid system, but some contradictory results were obtained in the case of time-dependent processes. Theoretical and experimental problems to be solved are discussed.Atliktas palyginamasis dviejų kompleksinių sistemų - Cu|Cu(II), glicinas ir Cu|Cu(II), maleino rūgštis - elektrocheminių charakteristikų tyrimas. Nustatytos maleino rūgšties tirpalų pusiausvyrinės charakteristikos. Kiekybiniam titravimo kreivių aprašymui išvestos lygtys, kuriose įvertinti medžiagų bei krūvių balansai bei atsižvelgta į praskiedimo efektus. Jų taikymas pH-metrinių duomenų analizei davė tokias maleato anijonų protonizacijos konstantų reikšmes: log = 6,05, log = 7,48. Nustatyta, kad tirpaluose su 0,3 M K2SO4 priedu protonizuotų ligando formų stabilumas sumažėja (log = 5,75, log = 7,30). Cu(II) maleatinių kompleksų stabilumui nustatyti panaudotas spektrofotometrijos metodas ir pasiūlyta duomenų analizės procedūra. Ji remiasi kiekybiniu absorbcijos spektrų aprašymu, taikant lygtis, išplaukiančias iš valdomo harmoninio osciliatoriaus teorijos. Išanalizavus įvairių sudėčių tirpalų absorbcijos maksimumo dydžius, prieita išvados, kad rūgščiose terpėse vyrauja monoligandinis kompleksas, kurio koncentracinė stabilumo konstanta log b1 = 2,2. Atlikta sistemos Cu|Cu(II), maleino rūgštis pusiausvyrų termodinaminė analizė. Nustatyta, kad esant metalinio vario ir tirpalų sąlyčiui, sistemoje galimi gilūs virsmai, kurių metu iki 90 % Cu(II) transformuojasi į Cu(I). Teorines išvadas patvirtina eksperimentiniai duomenys, gauti spektrofotometrijos ir elektrocheminės kvarco kristalo mikrogravimetrijos metodais. Įvertinti Cu korozijos bei fazinių Cu2O sluoksnių susidarymo... [toliau žr. visą tekstą]
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Molina, Gonzalez Sonia. "Analyse du couplage des fonctions de filtration des suies et de réduction des NOx pour moteur diesel." Thesis, Lyon, 2017. http://www.theses.fr/2017LYSE1290.
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Les systèmes de post-traitement qui combinent diverses fonctionnalités dans un même dispositif catalytique sont considérées comme une solution efficace pour réussir l’objectif définie par les restrictives futures normes qui régulent les émissions de l'industrie automobile. Ils permettent non seulement de réduire les coûts intrinsèques dus à l’encombrement mais aussi, dans certains cas, de favoriser les réactions catalytiques par des effets thermiques ou synergiques. Ce concept est particulièrement étudié pour les moteurs Diesel dont la ligne d'échappement peut comprendre jusqu'à quatre éléments. La réduction des NOx peut être réalisée par réduction catalytique sélective de l'ammoniac sur filtre (NH3-SCRF) en utilisant des catalyseurs à base de zéolite échangée par Cu ou Fe. Ce filtre à suie catalysé assume simultanément deux fonctions: l'élimination des particules et la réduction des espèces de NOx vers N2 et de l’eau. En ce qui concerne les catalyseurs SCR, la couche active est classiquement déposée sur les parois d'un substrat de grande porosité dont les canaux sont bloqués à des extrémités alternatives. Une porosité accrue du substrat du filtre (tel que la cordiérite ou SiC) est nécessaire pour permettre le dépôt de la quantité de phase de catalyseur nécessaire pour le traitement des émissions gazeuses en assurant une filtration efficace et sans produire un effet de contre-pression du system. En plus, il est nécessaire de remarquer que des nouvelles réactions se produiront dans ce système puisque la suie Diesel, le NOx et l'agent réducteur sont présents dans la même unité pour la première fois. Selon la littérature actuellement disponible, les polluants et la suie peuvent interagir de trois manières principales: 1) la suie bloque l'accessibilité du flux gazeux aux sites actifs «classiques» du catalyseur; 2) possibilité de réduction des NOx sur les particules de suie; et enfin, 3) la présence de suie affecte les performances des réactions SCR ou, au contraire, les réactions SCR affectent le processus d'oxydation des particules jusqu'à ce que la compétition pour le NO2 soit produiteAftertreatment systems that combine various functionalities into the same catalytic device are considered to be an efficient solution to reach the target defined by the restrictive future emission standards that regulate the automotive industry emissions. They are able not only to reduce the intrinsic costs due to the packaging but also, in some cases, to promote catalytic reactions by thermal or synergistic effects. This concept is being particularly explored for Diesel engines whose exhaust line may comprise up to four separate elements. NOx abatement can be accomplished by ammonia selective catalytic reduction on filter (NH3-SCRF) using Cu or Fe-exchanged zeolite-based as catalysts. This catalysed soot filter assumes two functions, simultaneously: removal of particles and reduction of NOx species towards N2. Regarding the SCR catalysts, the active layer is conventionally deposited onto the walls of a high porosity substrate whose channels are blocked at alternative ends. An increased porosity of the filter (such as cordierite or SiC) substrate is required to allow the deposition of the amount of catalyst phase needed for the treatment of gaseous emissions while efficient filtration and without producing a backpressure effect. Furthermore, it is necessary to remark that new reactions will occur in this system as Diesel soot, NOx and the reductant agent are present in the same unit for the first time. Accordingly to the literature currently available, there are three main ways that NOx pollutants and soot may interact: 1) soot blocking the accessibility of gas flow to “classic” active sites of the catalyst; 2) possibility of NOx reduction takes place over the soot particles; and finally, 3) soot presence affects SCR reactions performance or, contrarily, SCR reactions affects PM oxidation process as far as competition for NO2 will be produced
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Ruggiero, Lígia de Oliveira. "Estudo da presença de pares de Cu+ - OCN- e Cu+ - CN- no cristal de KCl." Universidade de São Paulo, 1989. http://www.teses.usp.br/teses/disponiveis/54/54131/tde-06022014-101453/.
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O presente trabalho mostra um estudo sobre a presença de pares de íons de CN- - Cu+ e OCN- -Cu+, em cristais de KCl, usando técnicas de medidas de corrente de despolarização termoestimulada (I.T.C.) e Absorção óptica. A detecção destes pares foi feita através de um estudo sistemática de correlação entre as diferentes amostras aqui usadas: KCl + 1% KCN; KCl + 1% CuCl; KCl + 1% KOCN; KCl + 1% KOCN + 1% CuCl e KCl + 1% KCN + 1% CuCl. Deve ser ressaltado que a última amostra apresenta um tipo de impureza não intencional OCN- , cuja associação com o íon Cu+ também é observada. Na absorção ótica observamos bandas à temperatura ambiente em 210, 228, 242, 252, 260 e 290 nm para o cristal de KCl + 1% CuCl + 1% KCN, sendo que para o cristal de KCl + 1% KOCN + 1% CuCl não foi observado o último pico. As diferentes bandas são atribuídas às possíveis interações entre Cu+ e CN-, bem como Cu+ e OCN-. Quanto à técnica de ITC, as curvas obtidas por esta, para os três últimos cirstais citados acima, foram melhor ajustadas pela somatória de duas curvas singulares de ITC, cujas temperaturas de pico estão nas posições de 53 e 55 K; 54,3 e 56,6 K; 53,3 e 56,1 K, respectivamente. Em KCl + 1% KOCN a curva de mais baixa temperatura (curva 1) de ITC é atribuída à molécula (16O12C14N-) e a curva de mais alta temperatura (curva 2) é atribuída à molécula isotrópica (18O12C14N-). Para as amostras de KCl + 1% KOCN + 1% CuCl a curva 1 foi atribuída ao OCN- isolado e a curva 2 ao Cu+ perturbado pela presença do OCN-. Quanto ao cristal de KCl + 1% KCN + 1% CuCl, as duas técnicas propostas não foram suficientes para identificar a presença de pares Cu+ - CN-, necessitando, desta maneira, da utilização de outra técnica experimental, como por exemplo a da luminescência. A correlação dos resultados experimentais foi feita através dos parâmetros determinados do momento de dipolo (p), energia de ativação (Ea∗) e a temperatura de pico (Tm∗)The present work gives a study on CN- - Cu+ and OCN- -Cu+ coupled pairs doped KCl single crystal, by using Ionic Thermal Current (I.T.C.) and Optical absorption techniques. These pairs were detected through a systematic correlation study between different samples: KCl + 1% KCN; KCl + 1% CuCl; KCl + 1% KOCN; KCl + 1% KOCN + 1% CuCl and KCl + 1% KCN + 1% CuCl, were the last sample shows unporposely doping OCN-, compled with Cu+. The observed optical absorption bands, at room temperature, were in 210, 228, 242, 252, 260 and 290 nm for KCl + 1% CuCl + 1% KCN crystal. Only the last absorption band was not seen in KCl + 1% KOCN + 1% CuCl samples. Diferent bands are associated with possible interactions between Cu+ and CN-, as also Cu+ with OCN-. The ITC curves for the last three crystals were better fitted with two single ITC´s curves, whose temperature peaks are at 53 and 55 K; 54,3 and 56,6 K; 53,3 and 56,1 K, respectively. The lowest temperature ITC band (curve 1) in KCl + 1% KOCN is attributed to the (16O12C14N-) molecule and the highest temperature ITC band (curve 2) is due to the (18O12C14N-) isotropic molecule. For KCl + 1% KOCN + 1% CuCl samples curve 1 was associated with isolated OCN- and curve 2 with Cu+ perturbed with OCN-. With KCl + 1% KCN + 1% CuCl, the two techniques were not good enough to identify Cu+ - CN-, compling, it should be necessary to apply another type of techniques, like luminescence. The correlations of the experimental results were done through the determination electric dipole moment (p), activation energy (Ea∗) and temperature peak (Tm∗) parameters
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Майзеліс, Антоніна Олександрівна, Борис Іванович Байрачний, and Лариса Валентинівна Трубнікова. "Електроосадження композиційно-модульованих покрить (Cu-Ni)/(Ni-Cu)." Thesis, НТУ "ХПІ", 2011. http://repository.kpi.kharkov.ua/handle/KhPI-Press/20771.
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Kozlova, Olga. "Brasage réactif Cu/acier inoxydable et Cu/alumine." Grenoble INPG, 2008. http://www.theses.fr/2008INPG0072.
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Dans ce travail nous étudions les aspects physicochimiques et mécaniques des joints brasés cuivre/acier inoxydable et cuivre/alumine. Dans la partie physicochimique nous étudions la mouillabilité, la réactivité aux interfaces et la microstructure des joints brasés. La partie mécanique porte sur les joints cuivre/alumine obtenus par brasage réactif et comprend des tests de traction et des essais de décollement par poinçon. A partir de résultats obtenus nous proposons des solutions optimales d'assemblage en terme de température, de durée de brasage et de composition des alliages de brasureIn this work we study the physico-chemical and mechanical aspects of the copper/stainless steel and copper/alumina brazed joints. In the physico-chemical part we study the wettability, the reactivity at the interfaces and the microstructure of the brazed joints. The mechanical part relates to the copper/alumina joints obtained by reactive brazing and includes tensile tests and shaft loaded blister tests. From the results we propose optimal solutions of assemblies in term of temperature, brazing time and composition of the braze
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Badamikar, Anupam Shirish. "Effect of conditioners on Cu-Cu and Al-Cu high current density sliding electrical contacts." Thesis, Wichita State University, 2009. http://hdl.handle.net/10057/2524.
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This study was aimed at evaluating the performance of contact conditioners in sliding electrical contacts. Cu-Cu and Al-Cu sliding contacts have been tested at current densities up to 933 A/mm2 and 733 A/mm2 respectively.
A pin on disc type test setup was developed around a high speed lathe. The setup comprises of a mechanical loading system, test circuit carrying high current, customized electronics and a data acquisition system. The mechanical system consists of a mechanism for loading the pin at a constant pressure independent of wear and a three component piezoelectric force dynamometer. The high current circuit consists of power switch arrangement, a shunt resistance for measuring the current and current control resistances for setting the peak current. The electronics includes circuitry for triggering, and controlling the width of the current pulse. A four terminal contact voltage measurement was performed during sliding. The contact voltage, shunt voltage, normal and frictional force components were recorded using an A/D card continuously at a rate of 5 kHz. The average pin wear rate was obtained by measuring the weight and length of the pin before and after the test. Two different contact conditioners, a solid lubricant interface conditioner (SLIC) and Uniflor8511® a PTFE thickened lubricant from Nye Lubricants were used.
Test results for the copper-copper (C110) sliding with SLIC shows tremendous improvement in contact life. Contacts pre-conditioned with SLIC, loaded to 10 MPa normal contact pressure and subjected to 3.6 ms long current pulses of nominal current density 933A/mm2, survived for more than 4000 revolutions or passes (single pulse/rev) prior to the
galling and failure. Sliding under current occurred at an average friction coefficient of 0.24. In comparison, testing without any conditioner shows an average friction coefficient above 0.6 and that the pin fails in less than 9 revolutions.
Similar tests were carried out for Al 7075-T6 pin sliding on copper (C110) plate. Testing was carried out in three stages, namely, preliminary testing to evaluate performance of SLIC and Uniflor under high speed sliding, interrupted testing to identify test track condition in the initial stage of sliding and further additional circular testing. Preliminary test results showed that Al transfers from the pin to the copper plate under high current. Testing with SLIC it was found that that the conditioner is less effective in this sliding system considering the amount of Al transfer to the copper plate. Further additional testing has been performed using Uniflor8511.
Additional circular testing shows that the average wear rate for sliding without current is much smaller as compared to sliding with current. A new mode of wear, namely, cutting of the transfer layers by the pin in subsequent passes, has been observed to increase the wear rate significantly once galling begins. Results also show that the thickness of the lubricant layer has an effect, with a thin layer of lubricant showing considerably increased friction coefficient and increased Al transfer to the test plate. Repeat pass testing with re-lubrication of pin between two passes provides some improvement in the average pin wear rate obtained.
SLIC is a promising conditioner for high current density Cu-Cu sliding contacts but needs to be tested at higher sliding speeds. For Al-Cu sliding contacts, Uniflor8511 delayed the onset of galling to about 30-40 passes (up to 3 pulses/rev), but could not reduce transfer of Al from the pin to the Cu plate.Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Industrial & Manufacturing Engineering
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Bochi, Gabriel 1969. "Magnetic anisotropy in epitaxial Ni/Cu (001) thin films and Cu/Ni/Cu (001) sandwiches." Thesis, Massachusetts Institute of Technology, 1995. http://hdl.handle.net/1721.1/11514.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 1995.Vita.
Includes bibliographical references (leaves 156-161).
by Gabriel Bochi.
Ph.D.
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Ha, Kin 1966. "Magnetoelastic couplings in epitaxial Cu/Ni/Cu/Si(001)." Thesis, Massachusetts Institute of Technology, 1999. http://hdl.handle.net/1721.1/85312.
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Dolderer, Benedikt. "Zur molekularen Architektur von Cu(I)-Thiolatzentren in Cu-Thioneinen." [S.l. : s.n.], 2004. http://deposit.ddb.de/cgi-bin/dokserv?idn=973266295.
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Martin, Airton Abrahao. "Preparação e caracterização de cerâmicas supercondutoras nos sistemas Y-Ba-Cu-O e Tm-Ba-Cu-O." Universidade de São Paulo, 1988. http://www.teses.usp.br/teses/disponiveis/54/54132/tde-18122013-112538/.
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Neste trabalho estudamos a influencia da temperatura e tempo de reação e sinterização na preparação de amostras cerâmicas supercondutoras pelo método de reação no estado sólido. Os resultados indicam claramente que algumas propriedades destes supercondutores, tais como: temperatura crítica (Tc), susceptibilidade magnética (X), resistividade (ρ), microestruturas, densidade e porosidade aparente, sofrem forte influencia das condições de tratamento térmico. Foram preparadas várias amostras dos sistemas YBa2Cu3O6.5+x e TmBa2Cu3O6.5+x, sendo que a temperatura e tempo ideal de reação encontrados foram de 950°C por 6 horas e 925°C por 48 horas, respectivamente; ambas tratadas em fluxo de oxigênio. A caracterização destas amostras foram feitas pelas técnicas de difração de raios-x, técnica de quatro-pontas (medida da variação da resistividade pela temperatura), ponte de Hartshorn (para a medida da variação da susceptibilidade magnética pela temperatura), microscopia eletrônica de varredura (para análise das microestruturas) e método de imersão (para a medida da densidade e porosidade aparente). A maior temperatura crítica encontrada foi de aproximadamente 94K para YBa2Cu3O6.5+x e de aproximadamente 91K para o TmBa2Cu3O6.5+xThe influence of the temperature and time in the reaction and sinterization of superconducting ceramics prepared by a solid state reaction was determined. The results clearly showed that some of its properties, such as critical temperature (Tc), magnetic susceptibility (X), resistivity (ρ), microstructure, apparent density, and porosity undergo a strong influence of the preparation conditions. Some samples in the YBa2Cu3O6.5+x and TmBa2Cu3O6.5+x systems were prepared. The ideal reaction temperature and time were 950°C for 6 hours and 925°C for 48 hours, respectively. Both annealed in O2 flow. The sample characterization was made by using X-ray diffraction, standard four probe (measures the variation of resistivity versus temperature), Bridge of Hartshorn (the variation of susceptibility versus temperature), scanning electron micrograph (microstructure analysis), and immersion method (measures the apparent density and porosity). The greatest critical temperature was approximately 94K for YBa2Cu3O6.5+x and 91K for TmBa2Cu3O6.5+x
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Sommadossi, Silvana Andrea [Verfasser]. "Investigation on diffusion soldering in Cu-In-Cu and Cu-In-48Sn-Cu systems / Institut für Metallkunde der Universität Stuttgart ... Vorgelegt von Silvana Andrea Sommadossi." Stuttgart : Max-Planck-Inst. für Metallforschung, 2002. http://d-nb.info/965684601/34.
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Абдулов, А. Р. "Термодинамические свойства расплавов Cu-Ti-Zr, Cu-Ni-Ti, Cu-Fe-Ti и моделирование их склонности к аморфизации." Diss. of Candidate of Chemical Sciences, Донбасская государственная машиностроительная академия, 2008.
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Mineau, Laurent. "Précipitation dans les alliages de cuivre dilués Cu-Fe-Ti, Cu-Co-Ti et Cu-Fe-Co-Ti." Grenoble INPG, 1991. http://www.theses.fr/1991INPG0087.
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L'etude porte sur la precipitation dans des alliages a base de cuivre contenant moins de 1. 2 at% de fer, cobalt et titane dans un rapport fe+co/ti egal a 1 ou 2. La preparation de ces materiaux comporte une succession de maintien a haute temperature (>800c) termines par trempe destines a la remise en solution des elements d'addition et de rechauffage autour de 500-600c pour activer la precipitation. La precipitation est suivie par mesure de resistivite electrique et par mesure de durete. La microstructure des echantillons est caracterisee par microscopie electronique en transmission et microanalyse x. A haute temperature, les alliages ternaires cu-fe-ti sont biphases cu-fe2ti, les alliages ternaires cu-co-ti sont biphases cu-co-ti. Par mesure de resistivite, on evalue entre 0. 3 et 0. 5 at% la solubilite a 950c de co et ti ou de fe et ti dans le cuivre. Entre 500 et 600c, le retour de l'alliage vers l'equilibre se fait par etapes successives de dissolution-precipitation. Un seul alliage de composition sur la ligne cu-coti presente un comportement quasibinaire a toutes temperatures. Les autres alliages etudies tendent vers un equilibre a trois phases cu-m#2ti-mti (m=fe ou co). Dans les alliages quaternaires, la substitution de fe par co ralentit la cinetique de desaturation. Tous les alliages quaternaires de cette etude evoluent vers un equilibre triphase du type cu-mti-m#2ti. La composition des phases m#2ti et mti varie avec le rapport initial co/fe+co. Une precipitation abondante et son mecanisme complexe expliquent l'excellente conductivite electrique (>70% iacs) et le bon comportement mecanique de ces alliages qui peuvent etre utilises comme materiaux pour connecteur electrique
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Franjola, Lara Sebastián Patricio. "Molienda Reactiva De Aleaciones Cu-Nb-C y Cu-Ti-C." Tesis, Universidad de Chile, 2007. http://www.repositorio.uchile.cl/handle/2250/104784.
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Rivas, Aguilera Claudio Andrés. "Compactación y Sinterización de Polvos Obtenidos por Aleación Mecánica de Cu-1,2%pAl, Cu-2,3%pTi y Cu-2,7%pV." Tesis, Universidad de Chile, 2008. http://repositorio.uchile.cl/handle/2250/104868.
Full textAbstract:
El presente trabajo se enmarca dentro del proyecto FONDECYT Nº 1070294
ejecutado por un equipo de investigación de la Universidad de Chile. El objetivo general es
estudiar el efecto de la presión de compactación, la temperatura y el tiempo de sinterización
sobre polvos aleados mecánicamente de Cu-1,2%p Al, Cu-2,3%p Ti y Cu-2,7%p V, sobre su
densidad y microestructura tras sinterizar.
Se fabricaron las aleaciones a partir de polvos elementales de Cu, Ti, Al y V,
mediante molienda reactiva. Los polvos fueron compactados y sinterizados bajo atmósfera
reductora. Para cada aleación, se estudió la densidad final y microestructura resultante de 8
condiciones diferentes de compactación y sinterización, de acuerdo con un diseño factorial
del tipo 2N
, donde se consideraron los siguientes parámetros: (1) Presión de compactación
(200[MPa] y 400[MPa]), (2) Temperatura de sinterización (850[°C] y 950[°C]), (3) Tiempo
de sinterización (1[h] y 4[h]). Se realizaron ajustes mediante regresión lineal para describir el
efecto de la variación de la presión, temperatura y tiempo sobre la densidad de los materiales
obtenidos, y se describió la morfología de la porosidad residual mediante observación en
microscopio óptico.
La densidad final máxima obtenida fue, en orden creciente: Cu-V (66%, 400[MPa],
850[°C], 4[h]), Cu-Ti (65%, 400[MPa], 950[°C], 4[h]), y Cu-Al (77%, 400[MPa], 850[°C],
1[h]). El proceso de molienda reactiva dio lugar a partículas con forma de hojuela,
endurecidas por deformación, lo cual provocó que las aleaciones obtuviesen una densidad
final mucho menor que el cobre puro sinterizado (densidad 87%). Esto se debe a que el polvo
endurecido resiste la deformación durante la compactación, lo cual crea menos puntos de
contacto entre partículas, hace más lenta la sinterización, y da lugar a una menor densidad.
El elemento aleante influyó en el tamaño de partícula que se obtiene durante la
molienda, lo que se atribuye a los diferentes medios de molienda (hexano para Ti y V,
metanol para Al) y a la diferente dureza que confiere cada cerámica al formarse en el cobre
durante la molienda. A mayor tamaño de partícula, se obtuvo mayor densidad en verde,
menor densificación, y mayor densidad final, en correspondencia con la teoría.
Para las tres aleaciones, el aumento de la presión de compactación da lugar a una
mayor densidad en verde, una mayor densificación, y una densidad final mayor. Para mayor
presión se observa un engrosamiento de la microestructura debido a la mayor densidad de
dislocaciones del polvo, lo cual da lugar a una recristalización acelerada durante la
sinterización, y un mayor crecimiento del tamaño de grano.
Para las tres aleaciones, el aumento de la temperatura de sinterización produce mayor
densificación y una densidad final mayor. La temperatura es un parámetro importante en la
densidad final, ya que influye en forma exponencial en el coeficiente de autodifusión del
cobre. A mayor temperatura se observa un engrosamiento de la microestructura, con mayor
crecimiento del tamaño de grano, y los poros se esferoidizan.
Para las tres aleaciones, el aumento del tiempo de sinterización produce mayor
densificación, y una densidad final mayor. El tiempo es un parámetro poco relevante sobre la
densidad final, ya que la distancia de difusión depende de la raíz cuadrada del tiempo. No se
observan cambios en la microestructura al aumentar el tiempo de sinterización, a pesar de
que la densidad aumenta.
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Pazukha, Iryna Mykhailivna, Ирина Михайловна Пазуха, Ірина Михайлівна Пазуха, and О. В. Ісаєв. "Використання плівкової системи Cu/Cr як чутливого елемента датчика тиску." Thesis, Видавництво СумДУ, 2008. http://essuir.sumdu.edu.ua/handle/123456789/4273.
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Lebreton, Valérie. "Etude métallurgique et optimisation de la fabrication d’alliages à base de cuivre coulés en continu : analyse de la ségrégation et des phénomènes de précipitation dans les alliages CuNi15Sn8, CuNi6Si1.8Cr, CuTi3Al2 et CuTi3Sn2.75." Paris, ENMP, 2007. http://pastel.archives-ouvertes.fr/pastel-00667453.
Full textAbstract:
Les alliages de cuivre au béryllium, caractérisés par un durcissement structural, sont de par leurs propriétés mécaniques proches de certains aciers (Rm#1230MPa, Re0. 2#1060MPa, A%#6. 5 à l’état trempé écroui revenu). D’autre part, ils présentent de hautes conductivités thermiques et électriques (22%I. A. C. S), une bonne résistance à l’usure et à la corrosion, et ils sont amagnétiques. La conjugaison de ces différentes propriétés permet aux alliages de Cu-Be d’accéder à une large une gamme d'applications (disques de frein pour les avions, électrodes de soudage, ressort Bourdon de la source pour manomètre, cordes de guitare etc. ). Cependant, en plus du coût élevé du béryllium, le principal inconvénient de ces alliages est la présence d’oxyde de béryllium qui est nocif lorsqu’il est inhalé sous forme de poudre ou de vapeur. Malgré toutes les précautions qui peuvent être prises pendant l’élaboration de ces matériaux, le risque demeure. En conséquence, pour préserver des conditions environnementales saines, une politique de recherche d'alliages de substitution possédant des propriétés physiques et mécaniques aussi remarquable que les alliages de Cu-Be a été menée. Au terme d’une étude bibliographique deux principales familles d’alliages riches en cuivre se sont distinguées pour leurs propriétés mécaniques comparables à celles développées par les alliages Cu-Be riches en cuivre : les systèmes Cu-Ni-X (X=Sn, Si) et Cu-Ti-X(X=Al,Sn) dans le coin riche en cuivre. Néanmoins, ces alliages ne sont pas exempts de problème. Par exemple, l’étain a tendance à ségréger lors de la solidification des alliages du système Cu-Ni-Sn élaboré en coulée continue, sans compter que ces mêmes alliages présentent un faible allongement à rupture après revenu. Un autre exemple est la faible conductivité électrique des alliages Cu-Ti (<8%I. A. C. S) en comparaison avec le CuBe2. Donc, pour améliorer ces performances, une optimisation des compositions chimiques et des traitements thermiques s’est avérée nécessaire. A cette fin quatre premiers alliages ont été retenus : le CuNi15Sn8, le CuNi6Si1. 8Cr, le CuTi3Al2 et le CuTi3Sn2. 75. Les travaux de recherche ont débutés par une analyse microstructurale de la ségrégation et des états filés trempés de ces matériaux dans le but d’appréhender les difficultés pouvant être rencontrées lors de leur élaboration. La deuxième partie s’est axée sur les phénomènes de précipitation lors des revenus durcissants où la relation propriétés mécaniques/électriques et microstructure a été établie dans la mesure des connaissances actuelles. Le projet a ensuite été réorienté par les résultats obtenus sur chacun des alliages de référence. Ainsi, l’influence des éléments mineurs a complété l’étude du CuNi15Sn8 tandis l’affinement de la composition en éléments majeurs des alliages CuNi6Si1. 8Cr, CuTi3Al2 et CuTi3Sn2. 75 a été privilégié. Des alliages sont ainsi proposés pour une validation semi-industrielle avec un programme de caractérisation plus completThe copper-beryllium alloys characterized by a structural hardening present mechanical properties close to those of high steels (Rm#1230MPa, Re 0. 2#1060MPa, A%#6. 5). On the other hand, they present high thermal and electric conductivities (22%I. A. C. S), a good resistance to wear and to corrosion, and they are non magnetic. The conjugation of these different properties enables Cu-Be alloys to find a broad range of applications (brake discs for planes, welding electrodes, spring Bumblebee for manometer etc). However, in addition to the cost raised by béryllium, the main inconvenience of these alloys is the presence of the beryllium oxide that is harmful when it is inhaled as powder or fume. In spite of all precautions that can be taken during the processing of these materials, the risk stays. Thus, to preserve healthy environmental conditions, a politic of research of substitute alloys having physical and mechanical properties as remarkable as those of Cu-Be alloys has been led. On the basis of a literature survey, two main families of copper rich alloys can be distinguished for their mechanical properties similar to those developed by Cu-Be alloys: the Cu-Ni-X (X=Sn, Si) and Cu-Ti-X(X=Al, Sn) systems in the rich copper side. Nevertheless, these alloys are not exempt of problem. For example, during the solidification processing by continuous casting, tin segregates in the case of Cu-Ni-Sn alloys. After ageing, their elongation is weak. Another example is the electrical conductivity which is very low in the case of the Cu-Ti alloys (<8%I. A. C. S). Therefore, to improve these performances, an optimization of the chemical compositions and of the thermal treatments proved to be necessary. To this end, four alloys have been kept first: the CuNi15Sn8, the CuNi6Si1. 8Cr, the CuTi3Al2 and the CuTi3Sn2. 75. The research started by a microstructural analysis of the segregation and extrusion states of these materials with the objective to assess the difficulties enable to be met during their processing. The second part dealt with the phenomena of precipitation during tempering and the relation mechanical/electrical properties and microstructure has been established in the light of current knowledges. The project has been reoriented then by the results on each of the reference alloys. Thus, the influence of the quaternary and quinary addition elements completed the survey of the CuNi15Sn8 alloy while the refinement of the major elements of the CuNi6Si1. 8Cr alloys, CuTi3Al2 and CuTi3Sn2. 75 has been privileged. Some alloys are proposed for a semi industrial validation and for an exhaustive characterization program
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Tilliander, Ulrika. "Synthesis of nano sized Cu and Cu-W alloy by hydrogen reduction." Licentiate thesis, KTH, Materials Science and Engineering, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-353.
Full textAbstract:
The major part of the present work, deals with the reduction kinetics of Cu2O powder and a Cu2O-WO3 powder mixture by hydrogen gas, studied by ThermoGravimetric Analysis (TGA). The reduction experiments were carried out both isothermally and non-isothermally on thin powder beds over different temperature intervals. During the experiments, the reductant gas flow rate was kept just above the starvation rate for the reaction to ensure that chemical reaction was the rate-controlling step. The activation energy for the reactions was evaluated from isothermal as well as non-isothermal reduction experiments.
In the case of the reduction of Cu2O, the impact of the stability of the copper oxide on the activation energy for hydrogen reduction under identical experimental conditions is discussed. A closer investigation of additions of Ni or NiO to Cu2O did not have a perceptible effect on the kinetics of reduction.
In the case of the reduction of the Cu2O-WO3 mixture, the reaction mechanism was found to be affected in the temperature range 923-973 K, which is attributed to the reaction/transformation in the starting oxide mixture. At lower temperatures, Cu2O was found to be preferentially reduced in the early stages, followed by the reduction of the tungsten oxide. At higher temperatures, the reduction kinetics was strongly affected by the formation of a complex oxide from the starting materials. It was found that the Cu2O-WO3 mixture underwent a reaction/transformation which could explain the observed kinetic behavior.
The composition and microstructures of both the starting material and the reaction products were analyzed by X-ray diffraction (XRD) as well as by microprobe analysis. vi Kinetic studies of reduction indicated that, the mechanism changes significantly at 923 K and the product formed had unusual properties. The structural studies performed by XRD indicated that, at 923 K, Cu dissolved in W forming a metastable solid solution, in amorphous/nanocrystalline state. The samples produced at higher as well as lower temperatures, on the other hand, showed the presence two phases, pure W and pure Cu. The SEM results were in conformity with the XRD analysis and confirmed the formation of W/Cu alloy. TEM analysis results confirmed the above observations and showed that the particle sizes was about 20 nm.
The structure of the W/Cu alloy produced in the present work was compared with those for pure copper produced from Cu2O produced by hydrogen reduction under similar conditions. It indicated that the presence of W hinders the coalescence of Cu particles and the alloy retains its nano-grain structure. The present results open up an interesting process route towards the production of intermetallic phases and composite materials under optimized conditions.
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Tadepalli, Rajappa 1979. "Characterization and requirements for Cu-Cu bonds for three-dimensional integrated circuits." Thesis, Massachusetts Institute of Technology, 2007. http://hdl.handle.net/1721.1/38515.
Full textAbstract:
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2007.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Includes bibliographical references (p. 197-206).
Three-dimensional integrated circuit (3D IC) technology enables heterogeneous integration of devices fabricated from different technologies, and reduces global RC delay by increasing the device density per unit chip area. Wafer-level Cu-Cu thermocompression bonding provides an attractive route to 3D IC fabrication, with Cu serving as both the electrical and mechanical interconnection between adjacent device layers. While the bonding process is currently employed for such applications, the lack of quantitative understanding of the bond quality and reliability has made developing robust processes extremely challenging. The current work addresses this problem through the development and implementation of bond toughness measurement techniques that investigate the effects of thin film patterning, surface chemistry and process parameters on the Cu-Cu bond quality under a range of loading conditions. The four-point bend test was used to quantify Cu-Cu bond toughness, Gc, under mixed-mode loading and to develop an optimized process flow that enabled the creation of high- toughness bonds (> 5 J/m2) at a bonding temperature of 300 oC. Mixed-mode loading induces significant plastic energy dissipation in ductile layers, resulting in an overestimation of the true adhesive strength of the interface.
(cont.) The chevron test method has been developed to allow bond toughness measurements under mode I loading, thereby probing the 'true' work of adhesion of the bonded interface. Furthermore, analysis of the bonded chevron specimen with different layer thicknesses was performed to allow the specimen to be used to characterize the bonded interface under mixed-mode loading conditions. Chevron tests reveal that the toughness of patterned Cu films is a strong function of the feature size and orientation. For debond propagation across periodic bonded and unbonded regions, a pronounced increase in Gc was observed, compared to debond propagation along a continuous bonded interface. Effects of patterning were significantly different in ductile thermocompression and brittle fusion bonded systems, with the latter showing a reduction in toughness due to patterning. The ultimate limit of low temperature Cu-Cu adhesion was investigated using pull-off force measurements in Atomic Force Microscope (AFM) under ultra-high vacuum (UHV) conditions. These measurements show that the work of adhesion of Cu bonds created at room temperature is ~ 3 J/m2, similar to Gc for wafer-level bonds created at 300 oC and measured using the chevron test.
(cont.) Deliberate pre-adhesion exposure of the Cu surfaces to 10-6 Torr O2 leads to a dramatic reduction in adhesion (to 0.1 J/m2), suggesting the formation of a Cu oxide that is detrimental to the Cu-Cu bonding process. The UHV-AFM measurements suggest that strong Cu-Cu bonds can be created by bonding clean Cu surfaces at room temperature, thereby eliminating several thermal stability issues in the thermocompression bonding process. The thermal management problem in 3D ICs containing multiple device layers was examined using an analytical model of forced liquid cooling via Cu-sealed integrated microchannels. Integration of microchannels requires a reduction in the area available for interconnects and adhesion, causing a trade-off between the inter-layer bonded area and the size and density of the channels that can be included. The optimum channel density is a function of the achievable local Cu-Cu bond strength.
by Rajappa Tadepalli.
Ph.D.
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Безымянный, Ю. Г., А. Н. Высоцкий, А. Н. Колесников, В. А. Назаренко, and О. В. Талько. "Исследование модуля упругости ламинатов Ni+Cu и Ni+Ti+Cu акустическими методами." Thesis, НТУ "ХПИ", 2016. http://repository.kpi.kharkov.ua/handle/KhPI-Press/25876.
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Penghao, Zhang Elena Koroleva. "Mg effect in Cu enrichment by anodic oxidation on Al-Cu alloys." Thesis, University of Manchester, 2004. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.503685.
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Mazzanti, Francesco. "Studio dell'intorno locale di complessi antitumorali di Cu(I) e (II) tramite spettroscopia di assorbimento X." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amslaurea.unibo.it/9308/.
Full textAbstract:
In questo lavoro è presentato l'utilizzo della spettroscopia di assorbimento di raggi X applicata all'indagine inerente il numero e la natura degli atomi vicini di un centro metallico a due diversi stati di ossidazione [Cu(I) e Cu(II)] all'interno di complessi fosfinici e/o azotati. Gli spettri sono stati registrati nella loro completezza, comprendendo sia la soglia sia lo spettro esteso di assorbimento, e le transizioni elettroniche 1s→3d e 1s→4p sono state oggetto d'esame per avere indicazioni circa l'intorno locale del fotoassorbitore (l'atomo centrale). La tecnica più utilizzata, tuttavia, è stata l'analisi EXAFS (Extended X-ray Absorption Fine Structure) che ha permesso di determinare l’effettiva coordinazione di Cu(I) e (II) nel caso dei complessi studiati. Il metodo consiste nella costruzione di un segnale teorico più simile possibile a quello ottenuto sperimentalmente, e l’approccio per raggiungere questo obiettivo consiste nel seguire una procedura di fitting eseguita computazionalmente (tramite il pacchetto software GNXAS), per la quale è necessario un modello strutturale già esistente o creato ex novo da una molecola di partenza molto simile. Sarà presentato lo studio degli esperimenti ottenuti su campioni sia solidi che in soluzione: in questo modo è stato possibile effettuare un confronto tra le due forme dello stesso composto nonché si è potuto osservare i cambiamenti riguardanti l’interazione metallo-solvente a diverse concentrazioni. Come sarà mostrato in seguito, l’analisi sui solidi è risultata più affidabile rispetto a quella riferita alle soluzioni; infatti il basso rapporto segnale/rumore caratterizzante le misure di queste ultime ha limitato le informazioni ottenibili dai relativi spettri di assorbimento di raggi X.
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Correr, Sobrinho Lourenço 1960. "Ligas do sistema Cu-Al-Zn-Nb, Cu-Al e Cu-Zn : estudos da corrosão quimica e de algumas propriedades fisicas." [s.n.], 1991. http://repositorio.unicamp.br/jspui/handle/REPOSIP/289327.
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Orientador: João Manuel Domingos de Almeida RolloDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba
Made available in DSpace on 2018-07-13T23:36:24Z (GMT). No. of bitstreams: 1 CorrerSobrinho_Lourenco_M.pdf: 4734512 bytes, checksum: 569f73a3e6dcab008c7d35d1b1176426 (MD5) Previous issue date: 1991
Resumo: No presente estudo foi elaborada uma liga EXPERIMENTAL à base de Cu-Al-Zn-Nb, onde os elementos de maior ponto de fusão que compõem a liga EXPERIMENTAL, foram adicionados na forma de pó. Alguns ensaios foram realizados, como: análise química. Dureza Vickers, análise metalográfica, corrosão através da análise eletroquímica potenciocinética, contração de fundição, fluidez e tração. A análise química foi realizada por via úmida, enquanto o ensaio de Dureza Vickers numa máquina Vickers Limited, e a metalografia num aparelho NEOPHOT 21 (CARL ZEISS). Já os testes de corrosão foram realizados num aparelho tipo CORROSCRIPT - TUCUSSEL e a contração de fundição em um anel metálico similar ao utilizado por 'EARNSHAW POT.10'. Para o ensaio de fluidez, foram utilizadas telas de nylon similares, a usada por 'PRESSWOOD POT.36'. O ensaio de tração foi efetuado numa máquina de ensaio UNIVERSAL LOSENHAUSENWERK de acordo com a especificação n. 5 da 'A.D.A. POT.1'. Este estudo foi desenvolvido, comparando-se os resultados da liga EXPERIMENTAL com os obtidos de duas ligas comerciais à base de cobre DURACAST MS e GOLDENT LA. Para obtenção dos corpos de prova foi utilizada a técnica de fundição odontológica pelo método da cera perdida. As fundições foram executadas através de um maçarico gás-oxigênio numa centrifuga convencional. Os resultados da análise metalográfica revelaram que não houve a formação de solução sólida nas três ligas estudadas. A liga EXPERIMENTAL e DURACAST MS apresentaram uma resistência à corrosão superior à liga GOLDENT LA. Quanto à Dureza Vickers, a liga EXPERIMENTAL apresentou um valor maior em relação às outras duas ligas. O valor da contração de fundição da liga DURACAST MS foi superior e a liga EXPERIMENTAL apresentou valores de fluidez superiores em relação às duas ligas comerciais. Já para o ensaio de tração, a liga EXPERIMENTAL foi superior e a liga GOLDENT LA apresentou maior valor de alongamento em relação às outras duas ligas
Abstract: In the present study it was been developed an experimental alloy fo the Cu-Zn-Al-Nb base. Where the elements the most point of fusion, that compose the experimental alloy where odds in a power form. Some experiments were made, such as: metallographic analysis, corrosion by test eletrochemical potenciocinetic analysis, castability test, tensile test, casting of shrinkage, chemical analysis and Hardness Vickres. The chemical analysis has been made through moist medium, while the Hardness Vickers experiment has been made in a machine Vickers Limited and the metallographic analysis in a device called NEOPHOT 21 (CARL ZEISS). And the corrosion test has been realized in a device called Corroscript Tucussel and the casting of Shrinkage in a metal ring similar to the one used by 'EARNSHAW IND POT.10¿. For the castability test it was used nets of nylon similar to the one used by 'PRESSWOOD POT.36' and the tensile experiment was realized in a machine of the Universal test LOSENHAUSENNERK according to the expecification n. 5 of 'A. D. A. POT.1'. All this study was developed comparing the results of the experimental alloy with ones obtained with two comercial alloys to the base of copper DURACAST MS and GOLDENT LA. In order to obtain test samples, the routine dental casting tecnique, was used with lost wax method. The castings were executed through a gas/oxigen blowpipe in conventional centrifuge. The results from the metalographic analysis has revealed that there hasn't been formation of a solid solution in the three studied alloys. Lhe EXPERIMENTAL and de DURACAST MS alloys have presented a resistance to corrosion superior to the GOLDENT LA alloy. Concerning the Hardness Vickers, the EXPERIMENTAL alloy has presented a bigger value in relation to the other two alloys. The value of casting Shrinkage of the DURACAST MS alloy was superior and the EXPERIMENTAL alloy has presented superior values of castability in relation to the comercial alloys. And for the tensile test the EXPERIMENTAL alloy was superior and the GOLDENT LA alloy has presented a bigger alongation value in relation to the other two alloys
Mestrado
Materiais Dentarios
Mestre em Odontologia
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GUIMARÃES, JÚNIOR Walber Gonçalves. "Estudo Teórico da Adsorção de Gases Leves nas Redes Metalorgânicas SIFSIX-2-Cu, SIFSIX-2-Cu-i e SIFSIX-3-Cu." reponame:Repositório Institucional da UNIFEI, 2017. http://repositorio.unifei.edu.br:8080/xmlui/handle/123456789/807.
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O dióxido de carbono, assim como outros gases leves denominados gases estufa, afetam de maneira negativa o sistema de temperatura global, agravando o efeito estufa desde a primeira revolução industrial. Mesmo a concentração nunca ter sido constante, a atividade antropogênica fez com que concentração desses gases na atmosfera aumentar de maneira exponencial. Por essa razão, países adotam estratégias para reduzir a concentração desses gases na atmosfera. O sequestro e captura de gases mostrou-se ser uma medida promissora na redução de gases estufa. O uso de alcanoaminas foi de grande relevância nesse processo, porém seu custo de reciclagem foi se elevando ao ponto de ser um material inviável para a adsorção de gases estufa, em especial o CO₂ devido sua quantidade. A utilização de redes metalorgânicas, materiais híbridos que sua topologia consiste em ligantes orgânicos coordenados a nós metálicos. Esses materiais de alta porosidade e grande área superficial aumentou o interesse em diversos campos de estudo, desde a catalise heterogênea até o transporte controlado de fármacos. Em 1999, Omar Yaghi utilizou esses materiais para a adsorção seletiva de gases, com foco em CO₂. Recentemente, a família SIFSIX se mostrou promissora na captura seletiva de CO₂, utilizando de unidades orgânicas de 1,2-di(piridin-4-il)etino e pilares inorgânicos a base de SiF₆²⁻. Nessa família, as redes metalorgânicas SIFSIX-2-Cu, SIFSIX-2-Cu-i e SIFSIX-3-Cu mostraram-se capazes de realizar a adsorção seletiva de CO₂ com uma alta capacidade em relação as suas concorrentes. A estrutura SIFSIX-3-Cu é a atual recordista de captura seletiva de CO₂. Por isso, o mecanismo de adsorção para gases leves é investigado utilizando-se DFT. A adsorção dos gases CH₄, CO₂, CO, H₂, N₂ e O₂ nas redes metalorgânicas SIFSIX-2-Cu, SIFSIX-2-Cu-i e SIFSIX-3-Cu foi estudada, afim de se entender o processo de adsorção dessa família. Resultados indicam a seletividade do CO₂ ser produto de seu alto momento de quadrupolo, onde o grupo aniônico, SiF₆²⁻, teve um papel importante para a adsorção.
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Cowell, J. J. "New avenues in alkene epoxidation : selective oxidation on Cu{111} and Cu{110}." Thesis, University of Cambridge, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.598086.
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This work investigated the partial oxidation reactions of styrene on Cu{110} and Cu{111} and butadiene on Cu{111}. For the first time it has been shown that it is possible to epoxidise alkenes over single crystal copper surfaces, the reaction is not confined to silver alone. The techniques used included temperature programmed reaction spectroscopy (TPRS), auger electron spectroscopy (AES), X-ray photoelectron spectroscopy (XPS), near edge X-ray absorption fine structure (NEXAFS) and scanning tunnelling microscopy (STM). The work described in this dissertation involves the adsorption of styrene onto the Cu{111} and Cu{110} surfaces modified with oxygen and caesium. The styrene adsorbed flat on the surface and reacted with partially oxidised copper to give styrene epoxide at very high selectivity. Fully oxidised surfaces were found to be inactive to styrene epoxidation, the alkene desorbs without reacting and with no change in geometry. The change in reactivity is due to changes in the intrinsic surface properties rather than a change in the styrene bonding. The process does not appear to be desorption rate limited, there is no evidence for the long term residence of styrene epoxide on the copper surface, suggesting that the reaction is reaction rate limited. Caesium reduced the surface oxidation, reducing oxidised copper to give bare copper and caesium oxides. This was accompanied by an increase in the activity of styrene epoxidation without adversely effecting selectivity, this is directly the opposite behaviour to caesium on silver. Studies involving butadiene showed the same basic behaviour. Partially oxidised Cu{111} epoxidises butadiene to epoxybutene at high selectivity. No other side chain products were observed, unlike the case on silver. Caesium was found to increase the activity of this reaction, resulting in almost 100% conversion. Work was conducted to enhance the resistance of the surface to over oxidation, nitroxy species were found to have little effect due to the formation of surface nitrites not nitrates.
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Ghosh, Swatilekha. "Electrodeposition of Cu, Sn and Cu-Sn alloy from choline chloride ionic liquid." Thesis, University of Newcastle upon Tyne, 2013. http://hdl.handle.net/10443/2279.
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Copper, tin and their alloy deposits are popular for its various applications in industrial aspects like enhance corrosion resistance and provide decorative finish. This work concentrated on the fabrication of these coatings, accomplished by electrodeposition technique which allows the control of thickness and microstructure of the films. Previously these metals and alloy were electrodeposited from different aqueous electrolytes. However these baths suffer from various environmental issues and deposits suffers from H evolution and metal oxide formation. As a result solution 2 ionic liquid (IL) was proposed as an alternative. ILs are categorized as salts liquid at room temperature and consist only of cations and anions. Presently Choline chloride based IL was used due to its advantages of low cost, low melting point, low toxicity, low viscosity and high conductivity than other ILs. Physical properties of the ILs like density, viscosity and conductivity were measured with variation of temperature and concentration of added metallic salts. To determine the electrochemical properties of individual metals and alloy, voltammetry scans were carried out using various scan rates and agitation rates. For all these measurements the concentration of Cu and Sn were varied in a range of 0.01 to 0.2 M and 0.01 to 0.1 M respectively at temperature range of 25 to 55 °C using a platinum rotating disk electrode (RDE). Deposition experiments were then carried out under potentiostatic and galvanostatic conditions using a stainless steel RDE. Material properties of the deposits like crystalline structure, grain size, strain, deposit morphology and chemical composition were analyzed using x-ray diffraction (XRD), optical microscope and scanning electron microscopy (SEM). The measurement showed that density and viscosity decreases and conductivity increases with rise in operation temperature for the electrolyte with and without metal ions. The reduction of both the metal was found to be mass transfer control and limiting current for metal deposition was found. The diffusion co-efficient -7 2 -7 2 obtained for Cu and Sn in the IL system was 1.22x10 cm /s and 1.96x10 cm /s -3 respectively. For individual metal Cu and Sn, best deposits were obtained at 4.7x10 2 -3 2 A/cm and 1.6x10 A/cm respectively using RDE speed of 700 rpm at 25 °C. The Cu deposit showed face centered cubic structure of 66±10 nm grain size and that of Sn was 62±10 nm with tetragonal crystalline structure. The smooth and bright Cu-Sn alloy deposit was obtained by applying potential in the range of 0.35 to 0.36 V vs. Ag wire or -3 2 0.8 to 0.9x10 A/cm of RDE speed is 220 rpm at 25 °C. The obtained deposits showed orthorhombic CuSn structure with a grain size of 21±10 nm. On annealing the 3 crystalline structure changed to hexagonal CuSn structure and the crystalline size 103 was obtained as 77±50 nm.
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Lee, Poh Wah. "DESIGN AND OPTIMIZATION OF LOW-Cu AND Cu-FREE AUTOMOTIVE BRAKE FRICTION MATERIALS." OpenSIUC, 2013. https://opensiuc.lib.siu.edu/dissertations/724.
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The purpose of this research was to generate the knowledge for formulating low-Cu and Cu-free brake friction materials without using and releasing hazardous materials that are listed on Washington State and California State Senate Bills. Model brake material samples were manufactured and tested in the Friction Assessment and Screening Test (FAST) and the full scale automotive brake dynamometer (Dyno) using a SAE J2430 test procedure. The SAE recommended a J2430 test procedure which provided the necessary data for the Brake Effectiveness Evaluation Procedure (BEEP) by the Brake Manufacturers' Council. The newly developed low-Cu and Cu-free brake friction materials were formulated by modifying a typical Non Asbestos Organic (NAO) (T-Baseline) formulation and a typical Semi-Metallic (M-Baseline) formulation. The NAO Cu-free brake friction materials contain geopolymer and natural hemp fibers as a partial replacement of phenolic resin and synthetic Kevlar fibers, respectively. Friction performance and wear data from a series of FAST tests were used to train an artificial neural network, which was used to optimize the NAO Cu-free formulations. Then, the optimized low-Cu and Cu-free brake friction materials were tested on the Dyno. Dyno test results showed that all NAO Cu-free brake friction materials have passed the Brake Effectiveness Evaluation Procedure (BEEP), did not exhibit thermal fade when temperature was increased and were slightly sensitive to speed. The NAO Cu-free brake friction materials exhibits slightly lower average friction level when compared to the baseline materials (T-Baseline). The Cu-free brake friction materials, as well as the rotors, exhibit higher wear than the detected wear on the T-Baseline material. The semi-metallic low-Cu and Cu-free brake friction materials have also passed the BEEP. Dyno test results indicated that the semi-metallic low-Cu and Cu-free friction materials did not exhibit thermal fade and were slightly sensitive to speed. The semi-metallic low-Cu and Cu-free materials exhibited lower friction level and higher wear on the pads when compared to the M-Baseline material. The semi-metallic Cu-free material outperformed the M-Baseline material in term of rotor wear. Analyses using scanning electron microscopy (SEM) and energy dispersive x-ray (EDX) microanalysis on the tested materials show that the friction surface of the T-baseline material was covered with fully developed and stable friction layer (third body) consisting mostly of Fe-oxides, different forms of carbon and compounds of materials originally present in the bulk material. The NAO Cu-free materials (T30-15 and T30-16) did not develop a sufficient friction layer. The friction layer seemed to be responsible for the detected lower wear in the T-Baseline compared to the NAO Cu-free materials (T30-15 and T30-16), and it acted as a solid lubricant on the interface between the rubbing pad and the cast iron rotor lowering the adhesive forces. The friction and wear of the T-Baseline material was controlled by adhesive mechanisms. The NAO Cu-free materials (T30-15 and T30-16) with content of geopolymer replacing phenolic resin matrix exhibited extensive abrasive wear in addition to adhesive mechanisms. The capacity to form a friction layer on the surface plays a considerable role when lowering the wear of NAO brake friction materials. The friction layer was formed by compaction and interaction of brake wear particles, and its stability and character depend on the chemistry of the bulk materials in contact as well as the temperature, pressure and sliding speed during a friction process. SEM and EDX analyses also showed that the semi-metallic pads have developed friction layer on the friction surfaces. The difference was that the M-Baseline material had well developed friction layer, but the Low-Cu (M4) and Cu-free (M5) materials, had many smaller patches of friction layer disturbed on the surfaces.
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Rey, Nicolás Adrián. "Novos ligantes binucleantes e seus complexos metálicos do tipo Cu''-(µ-OH)- Cu''." Florianópolis, SC, 2008. http://repositorio.ufsc.br/xmlui/handle/123456789/91042.
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Tese (doutorado) - Universidade Federal de Santa Catarina, Centro de Ciências Físicas e Matemáticas. Programa de Pós-Graduação em Química.Made available in DSpace on 2012-10-23T18:10:58Z (GMT). No. of bitstreams: 1 252706.pdf: 4478654 bytes, checksum: 5d3f6eb1142362094fa61581d5595570 (MD5)
A oxidação de substratos orgânicos pelo oxigênio molecular sob condições brandas constitui reação de grande interesse para muitos processos sintéticos e industriais, tanto de um ponto de vista econômico quanto ambiental. Embora a reação de substâncias orgânicas com o dioxigênio seja termodinamicamente favorável, é cineticamente impedida devido ao estado fundamental triplete do O2. Nos sistemas vivos, uma série de notáveis catalisadores biológicos conhecidos pelo nome de enzimas promove reações oxidativas com uma enorme rapidez e especificidade. Entre elas, podemos citar o grupo das catecol oxidases (COs), metaloenzimas contendo um centro binuclear de cobre que catalisam a oxidação de orto-difenóis (catecóis) às respectivas orto-quinonas. Nos últimos anos, muitos esforços têm sido realizados na tentativa de imitar as várias funções enzimáticas, o que pode ser feito através da síntese de compostos modelos menores e mais simples, que possam assumir funções catalíticas análogas. No presente trabalho, foram preparados quatro novos ligantes binucleantes: 4-metil-2,6-bis[(6-metil-1,4-diazepan-6-il)iminometil]fenol (HL1), 2-[N,N-bis(2-piridilmetil)aminometil]- 4-metil-6-[(6-metil-1,4-diazepan-6-il)iminometil]fenol (HL2), 2-[N,N-bis(2-piridilmetil) aminometil]-6-[(2-hidroxifenil)iminometil]-4-metilfenol (H2L3) e 2-[N,N-bis(2-piridilmetil) aminometil]-6-[(2-hidroxifenil)aminometil]-4-metilfenol (H2L4). A partir destes ligantes, três complexos binucleares de cobre(II) inéditos, a saber, [Cu2( -OH)(L1)](ClO4)2·H2O (1), [Cu2( -OH)(L2)(ClO4)]ClO4 (2) e [Cu2( -OH)(L3)]ClO4 (3), todos eles contendo uma ponte do tipo -hidroxo entre os metais, foram sintetizados e caracterizados por análise elementar, espectroscopias IV e UV-vis, EPR, medidas magnéticas, eletroquímica e condutimetria. Os três compostos tiveram as suas estruturas elucidadas por difração de raios-X e se mostraram excelentes modelos estruturais para o sítio ativo das COs. Os complexos 1 e 2 e suas formas protonadas e desprotonadas foram igualmente caracterizados via titulações potenciométricas e espectrofotométricas e apresentaram também atividade oxidativa frente ao substrato modelo 3,5-di-terc-butilcatecol, podendo ser considerados então modelos funcionais para as COs. Adicionalmente, os três complexos foram capazes de promover a reação de hidrólise do substrato modelo bis(2,4-dinitrofenil)fosfato (BDNPP), assim como a clivagem do DNA plasmidial pBSKII. Foi feito ainda um estudo envolvendo cálculos teóricos em fase gasosa para o composto 1, utilizando-se a teoria do funcional de densidade (DFT). Com base nesta investigação, foi possível se atribuir o modo de coordenação do BDNPP ao cátion complexo [Cu2( -OH)(L1)]2+. Para o caso específico de 1 e 2, que possuem também atividade oxidativa, as atividades hidrolíticas acima descritas os transformam num interessante e raro exemplo de promiscuidade catalítica em sistemas biomiméticos. Finalmente, o efeito citotóxico de 1 e 2 foi testado em células de leucemia mielóide crônica da linhagem K562. Ambos os compostos foram ativos, sendo que 1 apresentou a maior citotoxicidade, com um valor para o parâmetro CI50 de 44,70 mol L-1.
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Estay, Díaz Roberto Ignacio. "Estudio de la Evolución de la Microestructura y Dureza de Aleaciones Cu-V y Cu-V-Al Durante su Fabricación por Molienda Reactiva y Extrusión." Tesis, Universidad de Chile, 2008. http://www.repositorio.uchile.cl/handle/2250/104871.
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Čelkytė, Indrė. "Cd, Cu diferencijuotas bei kompleksinis poveikis mažosioms plūdenoms (Lemna minor) ir vasariniams miežiams (Hordeum vulgare L.) esant skirtingam biologiniam prieinamumui." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2011. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2011~D_20110614_133015-19443.
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Norint ištirti vario (Cu) ir kadmio (Cd) įtaką augalams, augintiems skirtingose terpėse, buvo vertinamas diferencijuotas ir kompleksinis sunkiųjų metalų poveikis jų morfologiniams ir fiziologiniams rodikliams. Varis reikalingas mažais kiekiais kaip mitybos elementas, bet tampa toksišku esant didesnėms jo koncentracijoms aplinkoje. Kadmis neturi biologinės funkcijos ir gali būti toksiškas esant mažoms koncentracijoms, priklausomai nuo aplinkos sąlygų, jo cheminio būvio ir t.t. Tyrimo objektais buvo pasirinkti vasariniai miežiai (Hordeum vulgare L.) ir mažosios plūdenos (Lemna minor).
Šio darbo tikslas yra įvertinti ir palyginti Cd ir Cu poveikį esant skirtingam biologiniam prieinamumui iš vandeninės terpės ir dirvožemio. Tiriamas darbas buvo atliekamas dviem etapais. Visų pirma buvo tiriamas pavienis metalų poveikis Lemna minor. Savaitę jos buvo auginamos 0,1 µM; 0,5 µM; 1 µM; 10 µM; 50 µM ir 100 µM koncentracijos kadmio bei 1 µM; 5 µM; 10 µM; 50 µM ir 100 µM koncentracijos vario tirpaluose. Metalų mišinių koncentracijos, kuriomis buvo veikiamos Lemna minor, pasirinktos pagal diferencituotas, kuriose augalai išgyveno daugiau kaip pusę tiriamojo laikotarpio. Nustačius EC50 koncentracijas pagal tiriamojo parametro, lyginant su kontrole, sumažėjimą, apskaičiuota EC50 mišinio. Mišinio koncentracijos išreikštos kaip TU. Įvertinti Lemna minor biomasės prieaugio, augimo inhibicijos pokyčiai. Kompleksinio poveikio atveju augimo greičiui (EC50 mišinio = 2,5 TU) ir biomasės... [toliau žr. visą tekstą]The aim of this study was to investigate the influence of cadmium (Cd) and copper (Cu) to plants froms diferent growing medium and evaluate the single and combined effect to their morphologic and physiologic parameters. Cu is known as micronutrient. It is necessary for plants but becames toxic at higher concentrations. Cd doesn‘t have any biological function and can be toxic even at small concentrations. It‘s toxicity depends on environmental conditions, chemical state and etc. The subject of this research is agricultural plants summer barley (Hordeum vulgare L.) and water plants duckweed (Lemna minor). The purpose of study is to value and to compare Cd and Cu effects to plants from water and soil medium. The research was done in two stages. At first, the single heavy metal effect to Lemna minor was investigated. Plants were treated one week by 0,1 µM; 0,5 µM; 1 µM; 10 µM; 50 µM; 100 µM Cd and 1 µM; 5 µM; 10 µM; 50 µM; 100 µM Cu concentrations. Considered to single concentrations, combained concentrations were chosen. Concentrations in the mixtures was expressed as TU, as fraction of their median affective concentration (EC50). Biomass and growing inhibition were measured. Antagonistic responses to biomass (EC50 mix = 2 TU) and growth inhibition (EC50 mix = 2,5 TU) occurred with Cd+Cu mixture. The experiment was also done with summer barley (Hordeum vulgare L.). Two weeks they were grown in soil and water solutions affected by the same heavy metal concentrations like Lemna... [to full text]
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Caris, Joshua. "Heat Treatment Effects on Mechanical Behavior of Cu-15Ni-8Sn Produced via Powder Metallurgy." Case Western Reserve University School of Graduate Studies / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=case1184360740.
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Dalbey, Robert Z., and Kenneth D. Challenger. "Interface characterization of Cu-Cu and Cu-Ag-Cu low temperature solid state bonds." Thesis, 1987. http://hdl.handle.net/10945/22310.
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Liu, Shun Cai, and 劉順財. "Electromigration tests in Cu/SnAg/Ni/Cu Flip Chip solder joints and Cu/SnAg/Cu microbumps." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/95944968763845461265.
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碩士國立交通大學
材料科學與工程學系所
103
Due to the growing demands for high performance, small form factor and multi-functions in microelectronic packaging for different types of portable electronic devices, 3D stacking is an important issue nowadays in ICs industry. The first part of this study was the electromigration test using two different bump heights (15 μm and 30 μm) of Cu/SnAg/Ni/Cu flip-chip samples. We can investigate the effect of the bump height effect of failure mode in electromigration. The current density of the experimental conditions is 1.33x104 A/cm2, 1.45x104 A/cm2 and 1.57x104 A/cm2, we can observe the failure mode is void formation, when Ni UBM at the cathode side. When the anode with Cu UBM, we also found serious copper dissolution. The second part is electromigration test of Cu/8 μm SnAg/Cu microbumps. The test temperatures were 135 °C, 150 °C and 165 °C on hot plates. We found some sample had early failure, and further explored the reasons for the failure, then we can avoid the early failure. The third part is about Cu/8 μm SnAg/Cu microbumps reflowing at different times. The microbumps were reflowed on a 260 °C hot plate for 0, 5, 10, 20, and 40 min to investigate the variation of Ag concentration in the residual SnAg solder and the morphology of Ag3Sn precipitations.
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Tseng, Yan-Lun, and 曾彥綸. "Effects of Minor Co Addition upon Sn-Cu/Ag, Sn-Cu/Ni,and Sn-Cu/Cu Interfacial Reactions." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/61212780969075630574.
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碩士中原大學
化學工程研究所
101
Minor Co addition into the solders is a promising method to improve the solder, and thus the soldering joint properties. However, the complete investigations regarding to the interfacial reactions between Co-alloying solders and the frequently encountered surface finish in electronic packaging industry i.e. Ni, Cu, and Ag are lacking. This thesis investigates the Cu-0.7wt%Cu-xCo/(Ni, Cu, Ag) interfacial reactions, where x ranges from 0.01 to 1wt%, and the Sn-0.7wt%Cu alloy is the commercial eutectic Sn-Cu solder. In 0.01-1wt%Co additions, Co does not alter the reaction phases but growth rate. Sn-0.7wt%Cu-Co/Ni interfacial reactions are similar to those of Sn-0.7wt%Cu/Ni. The reaction phases are the Ni3Sn4 and Cu6Sn5 phases. However, Co enhances the growth of the Ni3Sn4 phase, and the reaction phase growth is inhibited. Sn-0.7wt%Cu-Co/Cu interfacial reactions are similar to those of Sn-0.7wt%Cu/Cu. The reaction phases are the Cu3Sn and Cu6Sn5 phases. In contrast to those of Sn-0.7wt%Cu-Co/Ni, Sn-0.7wt%Cu-(Co)/Cu interfacial reactions are expedited by Co. In Sn-0.7wt%Cu-Co/Ag reaction couples, the Co effect is negligible because of the negligible solubility of Co in the Ag3Sn phase. Co dissolution refines the grains of the reaction phases. The kinetics of the Sn-0.7wt%Cu-xCo/(Ni, Cu, Ag) aging tests are determined in this thesis. The aging test kinetics data are essential to the reliability assessments of the soldering joints.
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Chou, Che-Yu, and 周哲佑. "Electrodeposition of Cu-WC Composite on Cu." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/32p76k.
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碩士國立臺北科技大學
材料及資源工程系研究所
98
In this study, WC particles and copper were deposited on copper simultaneously by electrodeposition to form the (0~35 vol.%) WC-copper composite layer. Such coating is believed to improve both mechanical properties while maintaining the excellent thermal conductivity of pure copper. The optimal condition for pure copper electrodeposition was 15℃, 30 min. Different ionic additives are added to control surface morphology and microstructures of copper coatings. For K+ ion, the coating grew along <200> to form awl-like surface structure, and for Cl-, the coating grew along both <200> and <220> and formed ladder-like surface structure. When Cl- ion was used as additive, it reduced heterogeneous nucleation and form continuous composite layer. 90% of pure copper thermal conductivity can be achieved. The hardness of Cu-WC coatings increased with WC content. The highest hardness value achieved 120 Hv0.01 in comparison with 60 Hv0.01 of pure copper. WC particles were also mechanically alloyed with Ni powders before composite deposition to improve WC-Cu bonding. The Ni-WC containing copper composite coating demonstrated hardness level up to 400 Hv0.05.
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Kozlova, Olga. "BRASAGE REACTIF CU/ACIER INOXYDABLE ET CU/ALUMINE." Phd thesis, 2008. http://tel.archives-ouvertes.fr/tel-00402086.
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Dans ce travail nous étudions les aspects physicochimiques et mécaniques des joints brasés cuivre/acier inoxydable et cuivre/alumine. Dans la partie physicochimique nous étudions la mouillabilité, la réactivité aux interfaces et la microstructure des joints brasés. La partie mécanique porte sur les joints cuivre/alumine obtenus par brasage réactif et comprend des tests de traction et des essais de décollement par poinçon. A partir de résultats obtenus nous proposons des solutions optimales d'assemblage en terme de température, de durée de brasage et de composition des alliages de brasure.
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Yi-kaiKuo and 郭亦凱. "Ga-doping effect upon Sn-0.7Cu/Cu interfacial reactions and the application of (Cu,Ga) nanoparticles on Cu-to-Cu interconnections." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/89413402345227814049.
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碩士國立成功大學
材料科學及工程學系
103
SUMMARY In recent years, soldering and three dimensional integrated-circuit (3D IC) take important parts of electronic packaging technology. Sn-based Pb-free solders have been widely used for low-temperature soldering. However, voids and brittle intermetallic compounds form at interfaces through Sn-based solder/Cu interfacial reactions. Doping elements into Sn-based solders is a common approach for improving joint reliability. In our previous work, minor addition of Ga has been found to effectively mitigate the soldering reactions between Sn-58Bi solders and Cu substrates. In this study, the reactions between Sn-0.7Cu-xGa (x = 1~3) solders and Cu substrates at 200 oC for various lengths of time up were investigated using electron probe micro analysis (EPMA) and CALPHAD thermodynamic modeling. The effect of Ga addition in Sn-0.7Cu solder is reported and the phase transformation in the Sn-0.7Cu-xGa/Cu couples is elaborated based on the Cu-Ga-Sn phase equilibria in the study. It is found that the reaction phase formation is strongly influenced by Ga concentrations. Besides, TSV process and Cu-to-Cu bonding are the crucial processes of 3D IC technology. The reactions of Cu/(Cu,Ga)NPs/Cu, Cu/Ni/(Cu,Ga)NPs/Ni/Cu and synthesized nanoparticles were investigated in this study. We proposed a bonding process for Cu-to-Cu in 3D IC with nanoparticles (NPs) synthesized by sonochemistry. After bonding process, a solid solution phase formed in the interface of Cu/Ni/(Cu,Ga)NPs/Ni/Cu and this result shows (Cu,Ga) nanoparticles have the great potential to develop in Cu-to-Cu process of 3D IC technology. Key words: Sn-0.7Cu solders, minor Ga addition, Cu-Ga-Sn phase equilibria, Sonochemistry, Nanoparticles, Cu-to-Cu bonding INTRODUCTION In recent years, soldering and three dimensional integrated-circuit (3D IC) take important parts of electronic packaging technology. Soldering has been changed to the key assembly and interconnection technology for electronic products including flip chip, ball grid array (BGA) process and 3D IC packaging. Sn-based Pb-free solders have been widely used for low-temperature soldering. However, some voids and brittle intermetallic compounds usually form at interfaces through Sn-based solder/Cu interfacial reactions. These brittle layer are called Kirkendall voids and these layer reduce the reliability of Cu-Sn joint. Doping elements into Sn-based solders is a common approach for improving joint reliability. Besides, in our previous research, adding the minor Ga into the Sn-58Bi alloy make a large difference of Sn-58Bi-xGa/Cu reaction. In this study, the reactions between Sn-0.7Cu-xGa (x=1~3) solders and Cu substrates at 200 oC were investigated while the reaction phase formation was also identified. The effect of Ga addition in Sn-0.7Cu solder is reported and the phase transformation in the Sn-0.7Cu-xGa/Cu couples is elaborated based on the Cu-Ga-Sn phase equilibria and CALPHAD thermodynamic modeling in the study. 3D IC packaging is the most important interconnection technology in the next generation electronic packaging industry including two important processes namely trough-silicon-via (TSV) process and Cu-to-Cu bonding. In our previous research, the Cu/Ga/Cu sandwich interfacial reactions were examined and the reaction phase formation was also identified. However, a brittle interface was found between Cu substrate and Ga solder. In this study, we proposed a bonding process for Cu-to-Cu in 3D IC with nanoparticles (NPs) synthesized by sonochemistry. The Cu/(Cu,Ga)NPs/Cu and Cu/Ni/(Cu,Ga)NPs/Ni/Cu reaction couples were bonded at 300 oC to set all condition the same as the real Cu-to-Cu interconnection in 3D IC technology. Furthermore, sonochemically synthesized nanoparticles was investigated and discussed in the paper. MATERIALS AND METHODS In the Sn-0.7Cu-xGa/Cu (x=1~3) interfacial reactions, the minor Ga is added into Sn-0.7Cu solders which were prepared by mixing proper amounts of pure Sn shot, pure Cu foil and pure Ga. The Cu foils were cut into pieces, and then metallographically grinded and polished with Al2O3 powders down to 1 μm. The samples were annealed at 200 oC under a 10-5 bar vacuum for predetermined lengths of times. Besides, the Cu-Ga-Sn ternary phase diagram was constructed based on calculation of phase diagram (CALPHAD) method. Furthermore, series of ternary Cu-Ga-Sn alloys were designed to do the phase equilibrium experiments at 200 °C to verify the phase relation of calculation isothermal section. This phase equilibria of the Cu-Ga-Sn ternary system were applied to investigate the mechanism of phase transformation and microstructural evolution in the interfacial reaction. In addition, the Cu/(Cu,Ga)NPs/Cu and Cu/Ni/(Cu,Ga)NPs/Ni/Cu sandwich-type reaction couples were prepared. The (Cu,Ga) nanoparticles were sonochemically synthesized by reducing copper sulfate with excessed Ga. The Ni under-bump metallization (UBM) layer was electroplated on each Cu substrate. Then the reaction couples were annealed at 300 oC for 6 hours. Finally, the compositions of IMCs were evaluated and determined by using EPMA, and the crystallography of compounds were detected by XRD to realize the mechanism of phase transformation and microstructural evolution. RESULTS AND DISCUSSIONS In the Sn-0.7Cu-1Ga/Cu annealed at 200 oC for 120 h couple, shown in Figure 1, according to EPMA analysis and Sn-Cu binary phase diagram, the compositions of the thick light gray and the scallop-type dark gray interfacial phases are determined to be η-Cu6Sn5 and ε-Cu3Sn phase with 2.34 at. % Ga and 1.97 at. % Ga, respectively. The phase formation of Sn-0.7Cu-2Ga/Cu annealed at 200 oC for 120 h couple, shown in Figure 2, were presumed to be the γ-Cu9Ga4 phase with 2.24 at. % Sn, η-Cu6Sn5 phase with 1.69 at. % Ga and the ε-Cu3Sn with 0.87 at. % Ga. Besides, the interfacial reaction of Sn-0.7Cu-3Ga/Cu annealed at 200 oC for 120 h couple is shown in Figure 3. With a slightly higher doping level of Ga, only one integral IMC layer on the interface was observed. This IMC phase was presumed to be γ-Cu9Ga4 phase with 2.53at. % Sn according to the analysis of EPMA and the Cu-Ga binary phase diagram. The difference between these three reaction couples can be due to the formation of the γ-Cu9Ga4 phase. The solid solubility of Sn in γ-Cu9Ga4 layer is around 2 at. %. After γ-Cu9Ga4 phase formed in the interface, Sn hardly diffused from solder to Cu substrates. The γ-Cu9Ga4 phase act as a native diffusion barrier of Sn to suppress the growth of Cu-Sn compound. Figure 1: Sn-0.7Cu-1Ga/Cu couples reacted at 200 °C for 120 hours Figure 2: Sn-0.7Cu-2Ga/Cu couples reacted at 200 °C for 120 hours Figure 3: Sn-0.7Cu-3Ga/Cu couples reacted at 200 °C for 120 hours Because the Kidkendall voids formation will cause serious reliability concern of joints, the major objective of this research is to avoid the Kirkendall voids formation. In the literature, several voids are formed due to the rapid diffusion of Cu in the ε-Cu3Sn phase. We compared Ga addition effect to the IMCs thickness, shown in Figure 4. It is indicated that the Ga addition increases as the thickness of total IMC decreases, and the thickness of ε-Cu3Sn decreases as well. It is suggested the Ga addition effectively reduces the thickness of ε-Cu3Sn growth, and even the interfacial reaction only forms the Cu-Ga compounds in the 3 wt. % Ga addition couple. In this situation, the Kirkendall voids can be avoid. Figure 4: IMCs thickness in different Ga addition at 200 °C for 120 hours Figure 5 is XRD analysis of nanoparticles synthesized by reducing copper sulfate with excessed Ga. The results show Cu peak slightly shift toward left indicating lattice expansion. Cu peak shifting is due to a part of Ga dissolves into FCC-(Cu) solid solution and the remaining Ga still exists in the nanoparticles after the synthesis of nanoparticles. After bonding process, γ2-Cu9Ga4 is formed at the interface which had a brittle structure in Cu/(Cu,Ga)NPs/Cu couple. However, a uniform joint of FCC-(Cu,Ga,Ni) solid solution phase formed at the interface of Cu/Ni/(Cu,Ga) NPs/Ni/Cu, shown in Figure 6. It is indicated that (Cu,Ga) nanoparticles dissolved into FCC-(Cu,Ni) because Ga has high solubility of FCC-(Cu) and FCC-(Ni). Figure 5: XRD plots of (Cu,Ga) prepared using copper sulphate solution (0.175 M, 20 mL) and Ga metal (0.5 g) after 3 min sonication Figure 5: Cu/Ni/(Cu,Ga)NPs /Ni/Cu couples annealed at 300 °C for 6 hours CONCLUSIONS In this research, the phase transformation in the Sn-0.7Cu-xGa/Cu (x=1~3) interfacial reactions was presented. The solubility of Sn is very low in γ-Cu9Ga4 layer, so γ-Cu9Ga4 layer can act as a native diffusion barrier of Sn to suppress the growth of Cu-Sn compound. The Ga addition strongly reduces the thickness of ε-Cu3Sn growth, and even the interfacial reaction only forms the Cu-Ga compounds in the 3 wt. % Ga addition couple. In this situation, the Kirkendall voids can be avoid. Furthermore, a part of Ga dissolves into FCC-(Cu) solid solution and the remaining Ga still exists in the nanoparticles after the synthesis of nanoparticles. In addition, the Cu/Ni/(Cu,Ga) NPs/Ni/Cu couple had a uniform joint of FCC-(Cu,Ga,Ni). The joints proved this process has great potential to be applied and developed in Cu-to-Cu process of 3D IC technology.
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Smith, Nathan Glenn. "Transpositions CU." Thesis, 2006. http://hdl.handle.net/1911/71884.
Full textAbstract:
The demarcations of territorial urban isms have not embedded within themselves with the potential to negotiate in the city-to-come. Transpositions CU considers the UNAM's Ciudad Universitaria (Mexico City) as a point of departure regarding the question of a delineated project's continuation within a city or larger national/political context. Do we abandon wholly past modalities or does our work operate, even if parasitically so, as an extension of present configurations and urban/infrastructural situations, anticipating the next move and abandoning the stabilization of histories and subject positions?
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Cheng, Show-Jye. "Cu NQR and NMR study of metal-substituted YBa Cu O and YBa Cu O." Thesis, 1995. http://hdl.handle.net/1957/34494.
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Keng, Huai Te, and 耿懷得. "Strength Determination of Cu TSV Chips by Considering Nonlinear Cu Material Property and Cu Pad." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/6688mn.
Full textAbstract:
碩士長庚大學
機械工程學系
104
For high-density 3D IC packaging applications, TSV (Trough Silicon Via) is a critical technology with more efficient transmission and lower power consumption. Because of the thermal expansion coefficient mismatch between silicon and copper via and thinner thickness of chip, the strength of silicon die with TSV structure is lower than that of normal silicon die. Thus, the purpose of this study is to evaluate the strength of TSV chips by a pin-on-elastic-foundation (PoEF) test and finite element method (FEM) simulation. Strengths of TSV chips are measured by PoEF test, and those experimental results are with those from the FEM simulation and the literature. The results show that failure initiation occurs at loaded copper via on the ground side of the chips. When the chips were loaded at failure loading, the crack was initiated from the silicon dioxide layer between the copper via and silicon. However, interface delamination between the copper pad and the ground side surface has occurred much earlier because the bonding strength between both is much weaker. And calculated maximum failure stress with considering silicon dioxide is lower than that without it. The thermal residual stress of TSV chips has only minor contribution to its mechanical strength. In comparison with experimental and simulation results, the strength of TSV chips without considering nonlinear material property of copper would be over predicted.
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Chan, Po-Fan, and 詹博帆. "The Control Methods for Electrodeposited Cu Microstructure and Geometry - Applications in the Cu Foil Manufacture,Cu Microvias Filling and Cu/Sn Joints." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/36846060712699672631.
Full textAbstract:
博士國立中興大學
化學工程學系所
105
The microstructure and deposition geometry of electrodeposited Cu are controlled by tuning the chemical parameters (e.g., the concentration of plating additives and the pH value of the plating solution) and the physical parameters (e.g., the convection of the plating solution and the operating current density). The deposition geometry is usually subject to the complex cathodic geometric surface; therefore, the thickness of the electrodeposited Cu is non-uniform because the tip effect that current prefers to pass through the peak position on the cathode. The geometric shapes we faced in this study are trenches, vias and holes, which are wildly used in the IC and PCB industries. To understand the fluid behavior of the electroplating fluid, the convection of electroplating solution between the cathode and the anode is simulated using COMSOL Multiphysics®. The formation and the orientation of the twin boundary in the electrodeposited Cu can be controlled by tuning the mode of flow field and the strength of the shear stress on the cathodic surface. This study provides readerships who study the electrodeposition a thought way from the view point of fluid mechanics to give insight into the electrochemical deposition process. The cathodic potential under galvanostatic electrodeposition could be controlled by numerous chemical and physical parameters, and it was found that a spontaneous potential oscillation (SPO) correlated the crystalline Cu formation with ultra-large grains (ULGs). Moreover, the amplitude of the SPO depended on the potential range of negative differential resistance (NDR). Both twinned and ULG Cu can be applied to the copper foil industry. The NDR behavior of a copper electroplating solution also can be applied to the bottom-up filling electrodeposition. The NDR occurrence is explained by an electrochemical differential equation. The plating additives are divided into three classifications according to the NDR differential equation: the accelerator, the suppressor, and the chelator. The differential equation also can explain how the plating additive plays its role in the electrodeposition. On the other hand, different grain size Cu samples with and without twinned boundary are electrodeposited as study models for studying the interface reaction of Cu/Sn joint and the formation of intermetallic compounds (IMCs). The results show that the voids were eliminated when the Cu grain boundary was extremely few and the Cu grain size was pretty large. The root cause of the voids formation is attributed to the diffusion rate difference of the Cu atoms that are located at the grain boundary or the lattice.
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Lin, Yueh-Ju, and 林岳儒. "Cu and Cu-Al2O3 Powders for Thermal Management Devices." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/88936503981424373761.
Full textAbstract:
博士國立臺灣大學
材料科學與工程學研究所
98
Heat pipes have been widely applied in thermal management devices for notebook computers and light emitting diodes. But, there is still room for improvement. The first subject studied in this work is to improve the performance of heat dissipation by adjusting the characteristic of Cu powders. The other subject is to resolve the defects encountered during mechanical deformation during heat pipe assembly. These defects are mainly caused by the coarse grains, low hardness, and low strength of the sintered copper tubing. To improve the performance of heat dissipation, a copper with a low oxygen content, larger mean particle size, narrow particle size distribution, and spherical powder shape is preferred for preparing the porous Cu wicks. It is also noticed during evaluation of the heat dissipation performance that the permeability and the capillary pressure, which have been widely used in the past, can be replaced by the capillary speed, which is simpler and more accurate. For increasing the strength and the hardness, the oxide dispersion strengthened Cu (ODS Cu) has been used in rods, plates, or bars, which have simple cross-sections. In this study, the development of the ODS Cu is aimed for press-and-sintered and powder injection molded parts, which are net-shaped. To attain good distribution of fine alumina particles in the Cu matrix, three methods are used. The first one is to use the cementation process to form alumina in the powder. The second approach is to add metal-containing lubricant, which forms alumina during sintering. The third method is to form alumina using the high energy milling process and Cu-Al pre-alloyed powders. The results of the cementation method show that the relative density up to 99 % and the hardness of 45.4 HB can be attained with the addition of 0.108 wt% aluminum (0.456 vol% Al2O3). These properties are better than the 91.8 % and 32.4 HB of the alumina-free copper. For 0.263 wt% aluminum (1.111 vol%Al2O3), the density is 95.4 % and the hardness is 60.2 HB. The electrical conductivity of Cu-Al2O3 sintered compacts decreased with increasing amount of alumina. The electrical conductivities of these two Cu-Al2O3 sintered compacts are about 84 %IACS, slightly higher than the 82.5 %IACS of the alumina-free copper. The results of adding metal-containing lubricant reveal that adding 1.0 wt% lithium stearate is effective and increases the relative density of sintered compacts from 94.6% to 97.5%. In high energy milling process, the results exhibit that compact containing 0.117 wt% aluminum (0.498 vol%Al2O3) has the highest relative density of 96.5% and electrical conductivity of 83.1 %IACS. The highest hardness of compact is 33.7 HRB when the aluminum content in the compact is 0.587 wt% (2.453 vol%Al2O3). Considering the mechanical and electrical properties, the suggested optimum aluminum content is 0.352 wt% (1.483 vol%Al2O3), which gives a sintered density of 96.4 %, a hardness of 27.3 HRB, and an electrical conductivity of 82.3 %IACS.
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Liu, Chin-Chang, and 劉錦璋. "Physical properties of Cu-Pd and Cu-Ni alloys." Thesis, 1994. http://ndltd.ncl.edu.tw/handle/61734772914180348666.
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Leong, Hoi Liong, C. L. Gan, Kin Leong Pey, Carl V. Thompson, and Hongyu Li. "Effects of Applied Loads, Effective Contact Area and Surface Roughness on the Dicing Yield of 3D Cu Bonded Interconnects." 2005. http://hdl.handle.net/1721.1/29818.
Full textAbstract:
Bonded copper interconnects were created using thermo-compression bonding and the dicing yield was used as an indication of the bond quality. SEM images indicated that the Cu was plastically deformed. Our experimental and modeling results indicate that the effective contact area is directly proportional to the applied load. Furthermore, for first time, results have been obtained that indicate that the dicing yield is proportional to the measured bond strength, and the bond strength is proportional to the effective contact area. It is also shown that films with rougher surfaces (and corresponding lower effective bonding areas) have lower bond strengths and dicing yields. A quantitative model for the relationship between measured surface roughness and the corresponding dicing yield has been developed. An appropriate surface-roughness data acquisition methodology has also been developed. The maximum possible applied load and the minimum possible surface roughness are required to obtain the maximum effective contact area, and hence to achieve optimum yields (both mechanically and electrically).Singapore-MIT Alliance (SMA)
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Lin, Wan-Hsuan, and 林宛萱. "Study of Metallurgical Reactions and Electromigration of 30μm Cu/SnAg/Ni and Cu/SnAg/Cu Microbumps." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/3yjhkv.
Full textAbstract:
碩士國立交通大學
工學院加速器光源科技與應用碩士學位學程
104
With intent to satisfy the demand of smaller electric component, the volume of solder continue shrinking. In three-dimensional integrated circuit, the microbump has been adopted to be interconnections between chips. The bump height decrease to 20μm or even lower. In this condition, the solder joint may transform into fully intermetallic compounds (IMCs) joint during electromigration (EM). In this study, we use the SnAg solder bump samples with the dimension of 30μm in width. There are two kinds of under-bump-metallization (UBM) were used: one type is Cu/Sn2.5Ag/Ni/Cu and another is Cu/Sn2.5Ag/Cu. We study the metallurgical reactions at liquid state and solid state. The bumps in the liquid state were reflow at 260°C and the process in the solid state were annealed at 150°C in the oven. In addition, we also conducted EM test in our samples with the current density 8x104 A/cm2. In the reflow and EM process, Cu/Ni system has faster dissolution rate in Copper UBM side than Cu/Cu system. The present of Nickel UBM at the substrate side can facilitate the Copper diffusion from the chip side. The different outcomes have been found in the annealing process. We explain the reasons in each process and also calculate the critical thickness of Copper UBM used in the Cu/Ni system.
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Lin, Po-Fan, and 林柏帆. "Study of Low Temperature Cu-to-Cu Direct Bonding with Chemical Mechanical Planarized Nanotwinned Cu Films." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/c4f25q.
Full textAbstract:
碩士國立交通大學
材料科學與工程學系所
105
Nowadays, the requirement of performance on microelectronic devices becomes higher while the size shrinks smaller. People use solder micro-bumps as the joints in microelectronic packaging. Solder joints have brittle IMCs (intermetallic compounds) and electromigration issues. Metal direct bonding is a promising approach to replace solder in microelectronic packaging, which can avoid the reliability issues caused by solders. Cu-to-Cu direct bonding was achieved at the temperature of 300°C-400°C, which is too high for microelectronic devices. Previous studies have shown the successful results of bonding two highly <111>-orientated nano-twinned Cu films fabricated by DC electroplating at low temperatures and with regular vacuum condition. It is because the Cu atoms have largest diffusivity on {111} planes. This breakthrough can lower the thermal budget and high vacuum environment on the bonding process. In this study we performed the DC electroplating to fabricate the <111>-oriented nt-Cu films. The current density is 80mA/cm2. In previous study, the nt-Cu films were electropolished at 1.75 V for 10 min and the roughness was 7nm. In this experiment, we perform the chemical mechanical planarization (CMP) to make the surface smooth for direct bonding. The nt-Cu films prepared by the CMP process can be bonded successfully in 10-3torr vacuum environment under the compressive stress of 0.78MPa. Owing to the lower surface roughness of 2nm, the CMP nt-Cu films bonding shows better bonding quality than the electropolished Cu films. The CMP nt-Cu films can be bonded successfully at 200°C in 10 min. In comparison, the bonding time for the electropolished nt-Cu films was 30min at 200°C.
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Yang, Kun-Hui, and 楊崑暉. "Study of Cu-Pd interdiffusion in preferred Cu(111) and Cu(220) under compressive stress 研 究." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/38937409425659507810.
Full textAbstract:
碩士國立中央大學
化學工程與材料工程學系
103
In recent years, three-dimensional integrated circuit (3D IC) has been agreed as the next generation semiconductor technology with the advantages of small form factor, high-performance, low power consumption, and high density integration. In the 3 type bonding technology: chip-to-chip, chip-to-wafer, and wafer-to-wafer., wafer-to-wafer technology can be applied for homogeneous integration of high yielding devices and plays important role in productive efficiency of 3D IC. However, wafer-to-wafer bonding technology also has the advantages in Thin-GaN LED: (1) uniform current spreading and (2) high emitting area. Therefore, wafer-to-wafer technology will be important technology in the future. In wafer-to-wafer technology, solid/solid metal bonding has the property that bonding can be finished at low temperature (150~250℃). It will be important for future development: (1) Prevent the formation of intermediary metal compounds (IMC) at bonding interface, (2) Avoid the residual stress which produced by CTE mismatch in high temperature process. Compare with Cu-Cu direct bonding, we find that Cu-Pd-Cu bonding can be finished at lower bonding temperature. Importantly, external stress can reduce the finished bonding temperature, which be attributed to reduced energy barrier in solid state interdiffusion. Therefore, base on the concepts of successful atom-vacancy diffusion’s probability in Boltzmann distribution, the important factor in the difference between Cu(111)-Pd and Cu(200)-Pd with external stress will be discussed.