Thesis (M.S.)--University of Michigan, 1982.

Thesis (Professional Degree)--University of Missouri, School of Mines and Metallurgy, 1938. / List of Illustrations on p. [iii] indicates a map of Central Peru is on p. 1. The map has been removed from original copy, and is therefore unavailable. The entire thesis text is included in file. Typescript. Title from title screen of thesis/dissertation PDF file (viewed June 29, 2010)

abstract: Miedema's plot is used to select the Cu/metal barrier for Cu metallization.The Cu/metal barrier system selected should have positive heat of formation (Hf) so that there is no intermixing between the two layers. In this case, Ru is chosen as a potential candidate, and then the barrier properties of sputtered Cu/Ru thin films on thermally grown SiO2 substrates are investigated by Rutherford backscattering spectrometry (RBS), X-ray diffractometry (XRD), and electrical resistivity measurement. The Cu/Ru/SiO2 samples are analyzed prior to and after vacuum annealing at various temperatures of 400, 500, and 600 oC and at different interval of times of 0.5, 1 and 2 hrs for each temperature. Backscattering analysis indicate that both the copper and ruthenium thin films are thermally stable at high temperature of 600 oC, without any interdiffusion and chemical reaction between Cu and Ru thin films. No new phase formation is observed in any of the Cu/Ru/SiO2 samples. The XRD data indicate no new phase formation in any of the annealed Cu/Ru/SiO2 samples and confirmed excellent thermal stability of Cu on Ru layer. The electrical resistivity measurement indicated that the electrical resistivity value of the copper thin films annealed at 400, 500, and 600 oC is essentially constant and the copper films are thermally stable on Ru, no reaction occurs between copper films and Ru the layer. Cu/Ru/SiO2 multilayered thin film samples have been shown to possess good mechanical strength and adhesion between the Cu and Ru layers compared to the Cu/SiO2 thin film samples. The strength evaluation is carried out under static loading conditions such as nanoindentation testing. In this study, evaluation and comparison is donebased on the dynamic deformation behavior of Cu/Ru/SiO2 and Cu/SiO2 samples under scratch loading condition as a measure of tribological properties. Finally, the deformation behavior under static and dynamic loading conditions is understood using the scanning electron microscope (SEM) and the focused ionbeam imaging microscope (FIB) for topographical and cross-sectional imaging respectively. / Dissertation/Thesis / M.S. Materials Science and Engineering 2010

Fungos patogênicos, como Cryptococcus neoformans e Candida albicans, são uma das mais frequentes causas de infecções oportunistas em todo o mundo, sendo capazes de sobreviver, proliferar e escapar de macrófagos, células de primeira linha da resposta imune de hospedeiros mamíferos. Macrófagos geralmente expõem o patógeno intracelular a um ambiente tóxico, caracterizado por pH ácido, presença de espécies reativas, como também de peptídeos antimicrobianos. Neste contexto, há uma competição entre o patógeno intracelular e o hospedeiro mamífero por nutrientes essenciais, como por exemplo, metais de transição. Cobre é um metal de transição essencial para a vida aeróbica, porém pode ser tóxico em altas concentrações e, devido a isto, diversos organismos desenvolveram mecanismos regulatórios para controlar suas concentrações. O objetivo deste trabalho foi avaliar a modulação da homeostase de cobre durante a interação entre macrófagos e células de C. neoformans ou C. albicans. Neste trabalho, foi possível demonstrar que a presença de cobre contribui para uma menor atividade fungicida de macrófagos infectados. Também, o pré-carregamento das células fúngicas com cobre alterou a sensibilidade de ambas leveduras patogênicas à atividade anti-fúngica. Além disso, foi demonstrado que a expressão de transportadores de cobre (CTR1 e ATP7A) e proteínas ligadoras de cobre (ceruloplasmina e metalotioneína 1) de macrófagos foram moduladas em resposta à infecção por estes fungos patogênicos. Entretanto, essa regulação pode envolver mecanismos mais complexos, como estratégias do patógeno para subverter a ação antimicrobiana de macrófagos. / Pathogenic yeasts, such as Cryptococcus neoformans and Candida albicans, are one of the most frequent causes of the opportunistic infections worldwide, being able to survive, proliferate and escape from macrophages, the first line cells engaged in the immune defense of the mammalian host. Macrophages generally expose the intracellular pathogen to a toxic environment, which is characterized by acid pH, presence of reactive species, as well the presence of antimicrobial peptides. In this context, there is a competition between intracellular pathogen and mammalian host for essential nutrients, such as transition metals. Copper is an essential transition metal for aerobic life, but can be toxic at high concentrations and, therefore, many organisms have evolved highly regulated mechanisms for controlling its concentration. In this work, we aim is evaluate a modulation of copper homeostasis during interaction between macrophages and C. neoformans or C. albicans cells. This work demonstrated that the presence of copper resulted in a lower fungicidal activity of infected macrophages. Also, the pre-loading of fungal cells with copper can alter the sensitivity of both pathogenic yeasts to an antifungal activity. In addition, we showed that the expression of macrophage copper transporters (CTR1 and ATP7A) and copper-binding proteins (ceruloplasmin and metallothionein 1) are modulated in response infection by pathogenic fungi. However, this regulation may involve more complex mechanisms, such as strategies of pathogen to subvert the antimicrobial action of macrophages.

Fungos patogênicos, como Cryptococcus neoformans e Candida albicans, são uma das mais frequentes causas de infecções oportunistas em todo o mundo, sendo capazes de sobreviver, proliferar e escapar de macrófagos, células de primeira linha da resposta imune de hospedeiros mamíferos. Macrófagos geralmente expõem o patógeno intracelular a um ambiente tóxico, caracterizado por pH ácido, presença de espécies reativas, como também de peptídeos antimicrobianos. Neste contexto, há uma competição entre o patógeno intracelular e o hospedeiro mamífero por nutrientes essenciais, como por exemplo, metais de transição. Cobre é um metal de transição essencial para a vida aeróbica, porém pode ser tóxico em altas concentrações e, devido a isto, diversos organismos desenvolveram mecanismos regulatórios para controlar suas concentrações. O objetivo deste trabalho foi avaliar a modulação da homeostase de cobre durante a interação entre macrófagos e células de C. neoformans ou C. albicans. Neste trabalho, foi possível demonstrar que a presença de cobre contribui para uma menor atividade fungicida de macrófagos infectados. Também, o pré-carregamento das células fúngicas com cobre alterou a sensibilidade de ambas leveduras patogênicas à atividade anti-fúngica. Além disso, foi demonstrado que a expressão de transportadores de cobre (CTR1 e ATP7A) e proteínas ligadoras de cobre (ceruloplasmina e metalotioneína 1) de macrófagos foram moduladas em resposta à infecção por estes fungos patogênicos. Entretanto, essa regulação pode envolver mecanismos mais complexos, como estratégias do patógeno para subverter a ação antimicrobiana de macrófagos. / Pathogenic yeasts, such as Cryptococcus neoformans and Candida albicans, are one of the most frequent causes of the opportunistic infections worldwide, being able to survive, proliferate and escape from macrophages, the first line cells engaged in the immune defense of the mammalian host. Macrophages generally expose the intracellular pathogen to a toxic environment, which is characterized by acid pH, presence of reactive species, as well the presence of antimicrobial peptides. In this context, there is a competition between intracellular pathogen and mammalian host for essential nutrients, such as transition metals. Copper is an essential transition metal for aerobic life, but can be toxic at high concentrations and, therefore, many organisms have evolved highly regulated mechanisms for controlling its concentration. In this work, we aim is evaluate a modulation of copper homeostasis during interaction between macrophages and C. neoformans or C. albicans cells. This work demonstrated that the presence of copper resulted in a lower fungicidal activity of infected macrophages. Also, the pre-loading of fungal cells with copper can alter the sensitivity of both pathogenic yeasts to an antifungal activity. In addition, we showed that the expression of macrophage copper transporters (CTR1 and ATP7A) and copper-binding proteins (ceruloplasmin and metallothionein 1) are modulated in response infection by pathogenic fungi. However, this regulation may involve more complex mechanisms, such as strategies of pathogen to subvert the antimicrobial action of macrophages.

Fungos patogênicos, como Cryptococcus neoformans e Candida albicans, são uma das mais frequentes causas de infecções oportunistas em todo o mundo, sendo capazes de sobreviver, proliferar e escapar de macrófagos, células de primeira linha da resposta imune de hospedeiros mamíferos. Macrófagos geralmente expõem o patógeno intracelular a um ambiente tóxico, caracterizado por pH ácido, presença de espécies reativas, como também de peptídeos antimicrobianos. Neste contexto, há uma competição entre o patógeno intracelular e o hospedeiro mamífero por nutrientes essenciais, como por exemplo, metais de transição. Cobre é um metal de transição essencial para a vida aeróbica, porém pode ser tóxico em altas concentrações e, devido a isto, diversos organismos desenvolveram mecanismos regulatórios para controlar suas concentrações. O objetivo deste trabalho foi avaliar a modulação da homeostase de cobre durante a interação entre macrófagos e células de C. neoformans ou C. albicans. Neste trabalho, foi possível demonstrar que a presença de cobre contribui para uma menor atividade fungicida de macrófagos infectados. Também, o pré-carregamento das células fúngicas com cobre alterou a sensibilidade de ambas leveduras patogênicas à atividade anti-fúngica. Além disso, foi demonstrado que a expressão de transportadores de cobre (CTR1 e ATP7A) e proteínas ligadoras de cobre (ceruloplasmina e metalotioneína 1) de macrófagos foram moduladas em resposta à infecção por estes fungos patogênicos. Entretanto, essa regulação pode envolver mecanismos mais complexos, como estratégias do patógeno para subverter a ação antimicrobiana de macrófagos. / Pathogenic yeasts, such as Cryptococcus neoformans and Candida albicans, are one of the most frequent causes of the opportunistic infections worldwide, being able to survive, proliferate and escape from macrophages, the first line cells engaged in the immune defense of the mammalian host. Macrophages generally expose the intracellular pathogen to a toxic environment, which is characterized by acid pH, presence of reactive species, as well the presence of antimicrobial peptides. In this context, there is a competition between intracellular pathogen and mammalian host for essential nutrients, such as transition metals. Copper is an essential transition metal for aerobic life, but can be toxic at high concentrations and, therefore, many organisms have evolved highly regulated mechanisms for controlling its concentration. In this work, we aim is evaluate a modulation of copper homeostasis during interaction between macrophages and C. neoformans or C. albicans cells. This work demonstrated that the presence of copper resulted in a lower fungicidal activity of infected macrophages. Also, the pre-loading of fungal cells with copper can alter the sensitivity of both pathogenic yeasts to an antifungal activity. In addition, we showed that the expression of macrophage copper transporters (CTR1 and ATP7A) and copper-binding proteins (ceruloplasmin and metallothionein 1) are modulated in response infection by pathogenic fungi. However, this regulation may involve more complex mechanisms, such as strategies of pathogen to subvert the antimicrobial action of macrophages.

The exotic orebodies related to cal-alkaline porphyry copper deposits. are sub-horizontal lenticular bodies of secondary copper minerals that impregnate Tertiary gravels and bedrock of different ages. They lie immediately downslope of the porphyry copper deposits, that is to say. they are related to the propylitic halo of the main deposits, and are considered to have originated with the deposition of copper minerals from solutions that overflowed during the secondary enrichment process. Supergene alteration took place between the late Oligocene and Miocene, by which time both orehodies (exotic and porphyry copper) were established. The paucity of tile denudation since the Miocene in the Andean segment from 21º to 26º latitude S. due to the dominance of a hyperarid climate explains the remarkable preservation of the shallow porphyry copper systems, supergene enriched blankets and associated deposits. This is reflected in the limonites, where the typical boxworks have been partially or totally destroyed on surface by the superleaching. As a result of the lateral migration of the copper-bearing solutions, the exotic deposits show a zonation. alteration and mineralization whose characteristics depend among other factors. on the reactivity of the bedrocks and the Cu/S ratio of the mother deposit. In these deposits three zones can be recognized: Proximal (0 to 2 km Intermediate (2 to 3) and Distal (3 to 8-14 km) with palaeodrainage control. The associations and mineralogical abundance are related to the climate (rain. temperature). In some deposits two important units are detected and they are the Cu-phosphates and Cu-lixiviable (to sulphuric acid) units. The size of tile Chilean exotic deposits varies between 100 and 3.500.000 tons of copper, with a total known resource of 8 M tons of copper. The large exotic deposits are comparable to the resources of a medium-sized porphyry copper- type deposit. The discovery of the exotic deposits is related to the exploration of porphyry copper deposits, where a mass balance of the leached column must be done. Moreover the lithology and alteration of the propylitic halo. permeability, structures, geophysics and geochemistry should be considered. The diorite model is not compatible with a supergene enrichment process, expressed by the absence of colour anomalies, exotic deposits and in the presence of secondary minerals like jarosite, which is coherent with the pyrite deficiency of the system. The projects are for exploitation of reserves by open pit methods. The projects plan to extract and to crush copper oxide ore which will he pre-treated with concentrated sulphuric acid prior to heap leaching, solvent extraction and electrowinning. The copper output varies between 10,000 and 50,000 ton per year of catilode copper. The total investment varies between 20 and 100 millions dollars. For project calculations, estimation of 65 % - 82 % copper recovery and 37 - 40 kg/ton net acid consumption can be used due to the nature of ore. The leaching time is estimated as 30 to 180 days for heaps of 4,5 to 30 metres high. As a result of this, the plant capacity is determined by an annual equivalent of 10,000 to 25,000 ton Cu per year. Pit planning has heen carried out using diverse software on the basis of 5 x 5 x 5 m and 10 x 10 x 10 m block models, evaluated using a kriging package built into the program, giving an overall waste/ore ratio (induding pre-stripping) of 0: I (in an outcrop) to 3: I. The location of the mine and plant sites are associated with the porphyry copper in production, for this the already installed facilities can be used. So there is no need to build a new mine camp or access. The environmental impact is summarized relating to the characterization of the physical, biological and socio-cuitural effects, using the framework of the Base Line study and the Impact evaluation derived from the construction and project operation phases. The conclusions and recommendations will diminish, mitigate and/or eliminate impact derived from the specific activities.

Electrodeposition method is used to deposit diamond-like carbon (DLC) films on copper substrates via anodic oxidation at low temperature. These films are characterized using Raman spectroscopy, Fourier transform infrared spectroscopy and scanning electron microscopy. Homogeneity of these films is studied using Raman spectroscopy and scanning electron microscopy. Scotch tape peel tests indicate adherent film on copper substrate. Carbon phase transformation is studied using thermal annealing experiments in conjunction with Raman spectroscopy and scanning electron microscopy. A cathodic electrochemical method is also studied to deposit diamond-like carbon films on copper substrates. However, films deposited by the cathodic route have poor adhesion and quality compared to anodically deposited films. It is also possible to grow diamond phase on copper substrates using acetylene in liquid ammonia via electrodeposition route. An electrochemical method is proposed for boron doping into DLC films.

Adherent Cu films were electrodeposited onto polycrystalline W foils from purged solutions of 0.05 M CuSO4 in H2SO4 supporting electrolyte and 0.025 M CuCO3∙Cu(OH)2 in 0.32 M H3BO3 and corresponding HBF4 supporting electrolyte, both at pH = 1. Films were deposited under constant potential conditions at voltages between -0.6 V and -0.2 V vs Ag/AgCl. All films produced by pulses of 10 s duration were visible to the eye, copper colored, and survived a crude test called "the Scotch tape test", which stick the scotch tape on the sample, then peel off the tape and see if the copper film peels off or not. Characterization by scanning electron microscopy (SEM), energy dispersive X-ray (EDX) and X-ray photon spectroscopy (XPS) confirmed the presence of metallic Cu, with apparent dendritic growth. No sulfur impurity was observable by XPS or EDX. Kinetics measurements indicate that the Cu nucleation process in the sulfuric bath is slower than in the borate bath. In both baths, nucleation kinetics do not correspond to either instantaneous or progressive nucleation. Films deposited from 0.05 M CuSO4/H2SO4 solution at pH > 1 at -0.2 V exhibited poor adhesion and decreased Cu reduction current. In both borate and sulfate baths, small Cu nuclei are observable by SEM upon deposition at higher negative overpotentials, while only large nuclei (~ 1 micron or larger) are observed upon deposition at less negative potentials.

In this work, copper bimetallic corrosion and inhibition in ultra large scale interconnect fabrication process is explored. Corrosion behavior of physical vapor deposited (PVD) copper on ruthenium on acidic and alkaline solutions was investigated with and without organic inhibitors. Bimetallic corrosion screening experiments were carried out to determine the corrosion rate. Potentiodynamic polarization experiments yielded information on the galvanic couples and also corrosion rates. XPS and FTIR surface analysis gave important information pertaining inhibition mechanism of organic inhibitors. Interestingly copper in contact with ruthenium in cleaning solution led to increased corrosion rate compared to copper in contact with tantalum. On the other hand when cobalt was in contact with copper, cobalt corroded and copper did not. We ascribe this phenomenon to the difference in the standard reduction potentials of the two metals in contact and in such a case a less noble metal will be corroded. The effects of plasma etch gases such as CF4, CF4+O2, C4F8, CH2F2 and SF6 on copper bimetallic corrosion was investigated too in alkaline solution. It was revealed that the type of etching gas plasma chemistry used in Cu interconnect manufacturing process creates copper surface modification which affects corrosion behavior in alkaline solution. The learning from copper bimetallic corrosion studies will be useful in the development of etch and clean formulations that will results in minimum defects and therefore increase the yield and reliability of copper interconnects.