Página 1 dos resultados de 865 itens digitais encontrados em 0.003 segundos

Hardness and structure characterization of Ti(6)Al(4)V films produced by reactive magnetron sputtering on a conventional austenitic stainless steel

Ospina, Carlos Mario Garzon; ALFONSO, Jose E.; CORREDOR, Edna C.; RECCO, Abel A.; Tschiptschin, Andre Paulo
Fonte: ELSEVIER SCI LTD Publicador: ELSEVIER SCI LTD
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
66.94%
Ti(6)Al(4)V thin films were grown by magnetron sputtering on a conventional austenitic stainless steel. Five deposition conditions varying both the deposition chamber pressure and the plasma power were studied. Highly textured thin films were obtained, their crystallite size (C) 2008 Elsevier Ltd. All rights reserved.

Electro-optically sensitive diamond-like carbon thin films deposited by reactive magnetron sputtering for electronic device applications

Rizzo, Vinícius Zacarias; Mansano, Ronaldo Domingues
Fonte: ELSEVIER SCIENCE SA Publicador: ELSEVIER SCIENCE SA
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
66.94%
The goal of this work is to study and relate electrical and optical properties of diamond-like carbon (DLC) thin films for applications in electronic devices. DLC films were deposited in a reactive RF magnetron sputtering system on p-type silicon and glass substrates. The target was a 99.9999% pure, 6 in. diameter graphite plate and methane was used as processing gas. Eight DLC films were produced for each substrate, varying deposition time, the reactor pressure between 5 mTorr and 10 mTorr while the RF power was applied at 13.56 MHz and varied between 100, 150, 200 and 250W. After deposition, the films were analyzed by I-V and C-V measurements (Cheng et al. (2004) [1]) in order to determine the electric resistivity, photo-current response and dielectric constant, optical transmittance, used to find the optical gap by the Tauc method; and by photoluminescence analysis to determine the photoemission and confirm the optical band gap. These characteristics are compared and the influence of the deposition parameters is discussed. (C) 2011 Published by Elsevier B.V.

The β to α phase transition of tantalum coatings deposited by modulated pulsed power magnetron sputtering

Myers, Sterling; Jianliang, Lin; Souza, Roberto Martins de; Sproul, Willian D; Moore, John J
Fonte: Lausanne Publicador: Lausanne
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
67.09%
Tantalum coatings are of particular interest today as promising candidates to replace potentially hazardous electrodeposited chromium coatings for tribological and corrosion resistant applications, such as the internal lining on large-caliber gun barrels. Tantalum coatings have two crystalline phases, α-Ta (body-centered-cubic) and β-Ta (metastable tetragonal) that exhibit relatively different properties. Alpha-Ta is typically preferred for wear and corrosion resistant applications and unfortunately, is very difficult to deposit without the assistance of substrate heating or post-annealing treatments. Furthermore, there is no general consensus on the mechanism which causes α or β to form or if there is a phase transition or transformation from β → α during coating deposition. In this study, modulated pulsed power (MPP) magnetron sputtering was used to deposit tantalum coatings with thicknesses between 2 and 20 μm without external substrate heating. The MPP Ta coatings showed good adhesion and low residual stress. This study shows there is an abrupt β → α phase transition when the coating is 5–7 μm thick and not a total phase transformation. Thermocouple measurements reveal substrate temperature increases as a function of deposition time until reaching a saturation temperature of ~ 388 °C. The importance of substrate temperature evolution on the β → α phase transition is also explained.

Filmes finos de carbono depositados por meio da técnica de magnetron sputtering usando cobalto, cobre e níquel como buffer-layers; Carbon thin films deposited by the magnetron sputtering technique using cobalt, copper and nickel as buffer-layers

Silva, Danilo Lopes Costa e
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 02/07/2015 PT
Relevância na Pesquisa
67.26%
Neste trabalho, foram produzidos filmes finos de carbono pela técnica de magnetron sputtering usando substratos monocristalinos de alumina com plano-c orientado em (0001) e substratos de Si (111) e Si (100), empregando Co, Ni e Cu como filmes intermediários (buffer-layers). As deposições foram conduzidas em três etapas, sendo primeiramente realizadas com buffer-layers de cobalto em substratos de alumina, onde somente após a produção de grande número de amostras, foram então realizadas as deposições usando buffer-layer de cobre em substratos de Si. Em seguida foram realizadas as deposições com buffer-layers de níquel em substratos de alumina. A cristalinidade dos filmes de carbono foi avaliada por meio da técnica de espectroscopia Raman e complementarmente por difração de raios X (DRX). A caracterização morfológica dos filmes foi feita por meio da microscopia eletrônica de varredura (MEV E FEG-SEM) e microscopia eletrônica de transmissão de alta resolução (HRTEM). Picos de DRX referentes aos filmes de carbono foram observados apenas nos resultados das amostras com buffer-layers de cobalto e de níquel. A espectroscopia Raman mostrou que os filmes de carbono com maior grau de cristalinidade foram os produzidos com substratos de Si (111) e buffers de Cu...

Hydrogen influence on gallium arsenide thin films prepared by rf-magnetron sputtering technique

Vilcarromero, J.; Bustamante, R.; da Silva, J. H. D.
Fonte: Sociedade Brasileira Fisica Publicador: Sociedade Brasileira Fisica
Tipo: Artigo de Revista Científica Formato: 1035-1037
ENG
Relevância na Pesquisa
66.94%
We investigate the effect of the hydrogen intentional incorporation on the structural properties of the amorphous gallium arsenide prepared by rf-magnetron sputtering technique. The properties of the non-hydrogenated films are: band gap of 1.4 eV (E-04), Urbach energy of 110 meV, stoichiometric composition ([As]/[Ga] = 0.50), and dark conductivity of about 3.2 x 10(-5) (Omega.cm)(-1). Hydrogen was incorporated in the films by the introduction of an electronically controlled H-2 flux during deposition, keeping constant the other deposition parameters. It was observed that small hydrogen incorporation produces a great change in the structural properties of the films. The main changes result from the formation of GaAs nanocrystals with mean sizes of about 7 nm into the amorphous network.

Growth and characterization of BaBi2Nb2O9 thin films made by RF-magnetron sputtering

Mazon, T.; Joanni, E.; Fernandes, JRA; Zaghete, M. A.; Cilense, M.; Varela, José Arana
Fonte: Taylor & Francis Ltd Publicador: Taylor & Francis Ltd
Tipo: Artigo de Revista Científica Formato: 201-207
ENG
Relevância na Pesquisa
66.94%
The RF-magnetron sputtering technique has been used to deposit polycrystalline thin films of layered-structured ferroelectric BaBi2Nb2O9 (BBN). The XRD patterns for the films annealed at 700degreesC for 1 hour show the presence of the BBN phase as well as the BaNb2O6 secondary phase. A better crystallization of the BBN phase and an inhibition of the secondary phase is obtained with the increase of temperature. The surface of the prepared films was rather dense and smooth with no cracks. The 300 nm thick BBN thin films exhibited a room-temperature dielectric constant of about 779 with a dissipation factor of 0.09 at a frequency of 100 kHz.

Effects of thermal annealing on the semi-insulating properties of radio frequency magnetron sputtering-produced germanate thin films

dos Santos Filho, S. G.; Sonnenberg, V.; Hora, W. G.; da Silva, D. M.; Kassab, L. R. P.
Fonte: Elsevier B.V. Sa Publicador: Elsevier B.V. Sa
Tipo: Artigo de Revista Científica Formato: 2695-2700
ENG
Relevância na Pesquisa
66.94%
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); We report the effects of thermal annealing on the semi-insulating properties of germanate thin films produced by a radio frequency magnetron sputtering process. Electrical and physical characterizations are presented. In the case of PbO-GeO2 films (annealed and not annealed), the electron diffraction analysis from transmission electron microscopy has shown that the amorphous structure predominates, whereas the annealed PbO-GeO2-AgNO3 (1 wt.%) films presented crystalline nanoparticles in the range of 1 to 9 nm composed of Pb, PbO and Ag4GeO4. Also, not annealed and annealed films were used to produce metal-insulator-semiconductor structures. The electrical properties of these structures were analysed from capacitance-voltage and conductance-voltage characteristics. The results showed that the significant leakage current in the accumulation region in the not annealed films can be increased by the annealing process. In addition, stable semi-insulating layers with an almost constant shifting of the capacitance-voltage characteristics are obtained when annealed PbO-GeO2-AgNO3 (1 wt.%) films are employed. Based on a proposed model accounting for the leakage process, the influence of this leakage on the accumulation capacitance was also established. In addition...

Structural transition of ZnO thin films produced by RF magnetron sputtering at low temperatures

Rosa, A. M.; Da Silva, E. P.; Chaves, M.; Trino, L. D.; Lisboa Filho, Paulo Noronha; Da Silva, T. F.; Durrant, S. F.; Bortoleto, J. R R
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 3143-3148
ENG
Relevância na Pesquisa
67.19%
Zinc oxide (ZnO) thin films were prepared using reactive radio-frequency magnetron sputtering of a pure metallic zinc target onto glass substrates. The evolution of the surface morphology and the optical properties of the films were studied as a function of the substrate temperature, which was varied from 50 to 250 C. The surface topography of the samples was examined using atomic force microscopy (AFM), and their optical properties were studied via transmittance measurements in the UV-Vis-NIR region. DRX and AFM analyses showed that the surface morphology undergoes a structural transition at substrate temperatures of around 150 C. Actually, at 50 C the formation of small grains was observed while at 250 C the grains observed were larger and had more irregular shapes. The optical gap remained constant at ∼3.3 eV for all films. In the visible region, the average optical transmittance was 80 %. From these results, one can conclude that the morphological properties of the ZnO thin films were more greatly affected by the substrate temperature, due to mis-orientation of polycrystalline grains, than were the optical properties. © 2013 Springer Science+Business Media New York.

Corrosion resistance of ZrNxOy thin films obtained by rf reactive magnetron sputtering

Ariza, E.; Rocha, L. A.; Vaz, F.; Cunha, L.; Ferreira, S. C.; Carvalho, P.; Rebouta, L.; Alves, E.; Goudeau, Ph.; Rivière, J. P.
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
Publicado em //2004 ENG
Relevância na Pesquisa
66.94%
The main aim of this work is the investigation of the corrosion resistance of single layered zirconium oxynitride, ZrNxOy, thin films in artificial sweat solution at ambient emperature. The films were produced by rf reactive magnetron sputtering, using a pure Zr target at a constant temperature of 300 8C. Two different sets of samples were produced. In the first set of films, the substrate bias voltage was the main variable, whereas in the second set, the flow rate of reactive gases (oxygen/nitrogen ratio) was varied. The control of the amount of oxygen allowed the film properties to be tailored from those of covalent zirconium nitride to those of the correspondent ionic oxide. The corrosion behaviour was evaluated by potentiodynamic polarization and Electrochemical Impedance Spectroscopy (EIS) tests. The analysis of EIS data provided detailed information of the corrosion processes occurring at the surface of the system throughout the immersion time. The modifications of the coating microstructure and/or chemical composition induced by the variation of the deposition parameters were also evaluated and correlated with the corrosion mechanisms occurring in each system.

Corrosion behaviour of substoichiometric TiNx films produced by DC magnetron sputtering

Ariza, E.; Rocha, L. A.; Vaz, F.; Rebouta, L.; Ferreira, J. A.; Alves, E.; Goudeau, Ph.; Rivière, J. P.
Fonte: Trans Tech Publications Publicador: Trans Tech Publications
Tipo: Conferência ou Objeto de Conferência
Publicado em /04/2003 ENG
Relevância na Pesquisa
66.94%
The present work describes the corrosion behaviour of substoichiometric TiNx films obtained by dc reactive magnetron sputtering. The coatings thickness ranged from 1.7 to 4.2 µm and the nitrogen content varied between 0 and 55 at. %. According to structural characterization by XRD, the films revealed a hexagonal α-Ti phase with a strong [002] orientation for low nitrogen contents. For nitrogen contents of 20% and 30%, the ε-Ti2N phase appears with a [200] orientation and further increasing of nitrogen content showed that the δ-TiN phase was dominant. Potentiodynamic polarisation and Electrochemical Impedance Spectroscopy (EIS) techniques were used to study the corrosion properties of TiNx films when immersed in artificial sweat solutions. Results of potentiodynamic polarisation tests showed that all films have a high corrosion resistance reflected by corrosion current densities values lower than 0.7µA/cm2. Also, EIS tests corroborated the results obtained in the polarisation tests, showing that films containing low percentages of nitrogen (less than 8 %) reveal the best corrosion resistance. Further increases in nitrogen content lead to a decrease in corrosion resistance. An exception to this behaviour was found for the film, with 30 % N. This sample presents an excellent corrosion resistance which increases with the immersion time. Higher nitrogen contents (52 and 55 %) promote a relative increase in the corrosion resistance when compared with 45 and 50 at % films...

Corrosion of TiN, (TiAl)N and CrN hard coatings produced by magnetron sputtering

Cunha, L.; Andritschky, M.; Rebouta, L.; Silva, R. A.
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
Publicado em 01/04/1998 ENG
Relevância na Pesquisa
66.94%
Metallic components like moulds, dies and machinery can be subjected to intensive degradation during plastic transformation processes, namely when working with fibre filler materials and plastics which release F, S or Cl during transformation. The degradation is attributed to the combined erosive and abrasive wear by the filler material and corrosive attack of agents. This degradation reduces the lifetime of the components considerably and has a direct impact on process productivity and surface finish of the final products. Nitride-based hard coatings like TiN, (TiAl)N, BN, etc. have proved their capability to increase tool lifetime when exposed to abrasive and corrosive environments found in plastic transformation processes halogenated polymers, acrylics, polyesters, fibre reinforced plastics, etc.. Within the frame of this work we produced TiN, (TiAl)N, CrN hard coatings, with and without a metallic interlayer, by dc and rf reactive magnetron sputtering, with a thickness of about 2 μm. The aqueous corrosion behaviour of the coatings was studied in saline and acidic environments by potentiodynamic and open circuit potential (OCP) measurements. The oxidation resistance during annealing in air was also studied. In saline NaCl 9% and acid HCl 3.4%environments we found that a metallic interlayer of Ti or Cr in the case of TiN– TiAl N-coated samples and CrN-coated samples...

Structural and optical properties of Ag : TiO2 nanocomposite films prepared by magnetron sputtering

Adochite, R.; Torrell, M.; Cunha, L.; Alves, E.; Barradas, N. P.; Cavaleiro, A.; Rivière, J. P.; Eyidi, D.; Vaz, F.
Fonte: INOE Publishing House Publicador: INOE Publishing House
Tipo: Artigo de Revista Científica
Publicado em /01/2011 ENG
Relevância na Pesquisa
66.94%
Three sets of nanocomposite films consisting of different atomic concentrations of Ag dispersed in a TiO2 dielectric matrix were deposited by DC reactive magnetron sputtering, and subjected to several thermal annealing experiments in vacuum, for temperatures ranging from 200 to 600 ºC. The main goal of the present study is to analyse the optical properties of the as-deposited and annealed films in order to clarify the role of Ag inclusions in the TiO2 dielectric matrix. The influence of the thermal annealing in the structural and morphological evolution was then correlated with the changes in the optical behavior of the samples. Significant structural and morphological changes were observed, consisting on the crystallization of Ag and their clustering. Clusters growth as a function of temperature was also observed by the evolution of the diffractograms with the temperature increase. The present study allowed to conclude that at certain concentrations (close to 10 at. %), the films revealed some important changes on the optical properties, commonly known as Surface Plasmon Resonance, SPR. This change in the optical behavior of the films was found to be in accordance with the clusters growth as concluded from the evolution of the diffraction patterns. The optical changes...

Optical properties of AlNxOy thin films deposited by DC magnetron sputtering

Borges, Joel; Alves, E.; Vaz, F.; Marques, L.
Fonte: SPIE Publicador: SPIE
Tipo: Artigo de Revista Científica
Publicado em /08/2011 ENG
Relevância na Pesquisa
66.94%
The aluminium oxynitride system offers the possibility to obtain a wide range of optical responses, by combining metallic aluminium, aluminium oxide and aluminium nitride properties, and thus opening a significant number of possible applications. The main purpose of the present work is to study the variation of the optical properties of AlN x O y thin films as a function of their composition (by varying both x and y coefficients), and the correspondent changes in their morphology and structure. The films were deposited by DC reactive magnetron sputtering, with the discharge parameters monitored during the deposition in order to control the chemical composition. The measurements reveal a smooth change of films Reflectance/Transmittance as a function of the concentration ratio of non metallic elements (O+N) to metallic Al, thus revealing the possibility to tailor the films optical properties according to the application envisaged.; Fundação para a Ciência e a Tecnologia (FCT) e ao Fundo Europeu de Desenvolvimento Regional (FEDER) – Programa Operacional “Ciência , Tecnologia, Inovação” – PTDC/CTM/69362/2006 e SFRH/BD/47118/2008

Electrical properties of AlNxOy thin films prepared by reactive magnetron sputtering

Borges, Joel; Martin, N.; Barradas, Nuno P.; Alves, E.; Eyidi, D.; Beaufort, Marie France; Riviere, J. P.; Vaz, F.; Marques, L.
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
Publicado em /06/2012 ENG
Relevância na Pesquisa
66.94%
Direct current magnetron sputtering was used to produce AlNxOy thin films, using an aluminum target, argon and a mixture of N2+O2 (17:3) as reactive gases. The partial pressure of the reactive gas mixture was increased, maintaining the discharge current constant. Within the two identified regimes of the target (metallic and compound), four different tendencies for the deposition rate were found and a morphological evolution from columnar towards cauliflower-type, ending up as dense and featureless-type films. The structure was found to be Al-type (face centered cubic) and the structural characterization carried out by X-ray 2 diffraction and transmission electron microscopy suggested the formation of an aluminumbased polycrystalline phase dispersed in an amorphous aluminum oxide/nitride (or oxynitride) matrix. This type of structure, composition, morphology and grain size, were found to be strongly correlated with the electrical response of the films, which showed a gradual transition between metallic-like responses towards semiconducting and even insulating-type behaviors. A group of films with high aluminum content revealed a sharp decrease of the temperature coefficient of resistance (TCR) as the concentration ratio of non-metallic/aluminum atomic ratio increased. Another group of samples...

Characterization and electrochemical behaviour of nanostructured calcium samarium manganite electrodes fabricated by RF-Magnetron Sputtering

Barrocas, B.; Sério, S.; Rovisco, A.; Nunes, Y.; Sá, A. I. Correia de; Pereira, M. I. da Silva; Jorge, M. E. Melo
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
Publicado em //2014 ENG
Relevância na Pesquisa
67.09%
Ca1-xSmxMnO3(0 . x . 0.4) films were successfully fabricated on Indium Tin Oxide (ITO) coated quartzglass substrates by radio frequency magnetron sputtering technique (RF- magnetron sputtering) fromcompacted nanosized powder targets, and subsequent annealing at 800.C in air, for 6 h. X-ray diffrac-tion shows a pure typical perovskite phase for x . 0.1. Scanning electron microscopy and atomic forcemicroscopy revealed that the films surface is dense, with low roughness, depending on the Sm content, even though a few cracks were observed. Crystallite size was found to decrease with the Sm content. Theelectrodes were characterized by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The oxide electrode fs capacitance was estimated using both techniques and the corresponding roughness factors evaluated. The values obtained from the two methods show a good agreement. A com-parison between the voltammetric data and those referred in the literature allowed finding out that theredox reaction occurring at the electrode surface involves the pair Mn4+/Mn3+. EIS measurements con-firm the voltammetric data and they also give additional information about the film porosity and the charge transfer resistance. This last parameter is associated with the oxidation and reduction of the pairMn3+/Mn4+and after normalized by the roughness factor shows an increase with samarium content.

Hydrogen influence on gallium arsenide thin films prepared by rf-magnetron sputtering technique

Vilcarromero,J.; Bustamante,R.; Silva,J.H.D. da
Fonte: Sociedade Brasileira de Física Publicador: Sociedade Brasileira de Física
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/09/2006 EN
Relevância na Pesquisa
66.94%
We investigate the effect of the hydrogen intentional incorporation on the structural properties of the amorphous gallium arsenide prepared by rf-magnetron sputtering technique. The properties of the non-hydrogenated films are: band gap of 1.4 eV (E04), Urbach energy of 110 meV, stoichiometric composition ([As]/[Ga] = 0.50), and dark conductivity of about 3.2 x 10-5 (omega.cm)-1. Hydrogen was incorporated in the films by the introduction of an electronically controlled H2 flux during deposition, keeping constant the other deposition parameters. It was observed that small hydrogen incorporation produces a great change in the structural properties of the films. The main changes result from the formation of GaAs nanocrystals with mean sizes of about 7 nm into the amorphous network.

Adição de nanopartículas de Ti em matriz de Fe através da deposição por magnetron sputtering

Ferreira, Narayanna Marques
Fonte: Universidade Federal do Rio Grande do Norte; BR; UFRN; Programa de Pós-Graduação em Ciência e Engenharia de Materiais; Processamento de Materiais a partir do Pó; Polímeros e Compósitos; Processamento de Materiais a part Publicador: Universidade Federal do Rio Grande do Norte; BR; UFRN; Programa de Pós-Graduação em Ciência e Engenharia de Materiais; Processamento de Materiais a partir do Pó; Polímeros e Compósitos; Processamento de Materiais a part
Tipo: Dissertação Formato: application/pdf
POR
Relevância na Pesquisa
67.36%
Microalloyed steels constitute a specific class of steel with low amount of carbon and microalloying elements such as Vanadium (V), Niobium (Nb) and Titanium (Ti). The development and application of microalloyed steels and steels in general are limited to the handling of powders with particles of submicron or nanometer dimensions. Therefore, this work presents an alternative in order to construction of microalloyed steels utilizing the deposition by magnetron sputtering technique as a microalloying element addiction in which Ti nanoparticles are dispersed in an iron matrix. The advantage of that technique in relation to the conventional metallurgical processes is the possibility of uniformly disperse the microalloying elements in the iron matrix. It was carried out deposition of Ti onto Fe powder in high CH4, H2, Ar plasma atmosphere, with two deposition times. After the deposition, the iron powder with nanoparticles of Ti dispersed distributed, were compacted and sintered at 1120 ° C in resistive furnace. Characterization techniques utilized in the samples of powder before and after deposition of Ti were Granulometry, Scanning Electron Microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX) and X-ray diffraction (DRX). In the case of sintered samples...

Construção de um aparato experimental para monitoramento in situ da deposição de filmes finos de titânio por magnetron sputtering; Construction of an experimental apparatus for in situ monitoring of thin film deposition by magnetron sputtering titanium

Nascimento, Igor Oliveira
Fonte: Universidade Federal do Rio Grande do Norte; BR; UFRN; Programa de Pós-Graduação em Ciência e Engenharia de Materiais; Processamento de Materiais a partir do Pó; Polímeros e Compósitos; Processamento de Materiais a part Publicador: Universidade Federal do Rio Grande do Norte; BR; UFRN; Programa de Pós-Graduação em Ciência e Engenharia de Materiais; Processamento de Materiais a partir do Pó; Polímeros e Compósitos; Processamento de Materiais a part
Tipo: Dissertação Formato: application/pdf
POR
Relevância na Pesquisa
67.26%
The technique of surface coating using magnetron sputtering is one of the most widely used in the surface engineering, for its versatility in obtaining different films as well as in the micro / nanometric thickness control. Among the various process parameters, those related to the active species of the plasma are of the most fundamental importance in the mechanism and kinetics of deposition. In order to identify the active species of the plasma, parameters such as gas flow, pressure and density of electric power were varied during titanium coating on glass substrate. By flowing argon gas of 10, 20, 30, 40 and 50 sccm (cubic centimeters per minute) for each gas flow a sequential scan of the electric current of 0.10, 0.20, 0.30, 0.40 , 0.50 A. The maximum value of 0.50 A was chosen based both on literature data and on limitations of the equipment. The monitoring of plasma species present during the deposition was carried out in situ by the technique of optical emission spectroscopy (OES) through the spectrometer Ocean Optics USB2000 Series. For this purpose, an apparatus was developed to adapt the OES inside the plasma reactor to stay positioned closest to the target. The radiations emitted by the species were detected by an optical fiber placed behind the glass substrate and their intensities as a function of wavelength were...

Structural and Mechanical Properties of Zr-Si-N Thin Films Prepared by Reactive Magnetron Sputtering

Freitas,Flávio Gustavo Ribeiro; Hübler,Roberto; Soares,Gabriel; Conceição,Amanda Gardênia Santos; Vitória,Edson Reis; Carvalho,Renata Gomes; Tentardini,Eduardo Kirinus
Fonte: ABM, ABC, ABPol Publicador: ABM, ABC, ABPol
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2015 EN
Relevância na Pesquisa
67.01%
Zirconium silicon nitride (ZrSiN) thin films were deposited by reactive magnetron sputtering in order to verify the silicon influence on coating morphology and mechanical properties. The Si/(Zr+Si) ratio was adjusted between 0 to 15% just modifying the power applied on the silicon target. Only peaks associated to ZrN crystalline structure were observed in XRD analysis, since Si3N4 phase was amorphous. All samples have (111) preferred orientation, but there is a peak intensity reduction and a broadening increase for the sample with the highest Si/(Zr+Si) ratio (15%), demonstrating a considerable loss of crystallinity or grain size reduction (about 8 nm calculated by Scherrer). It was also observed that the I(200)/I(111) ratio increases with silicon addition. Chemical composition and thickness of the coatings were determined by RBS analysis. No significant changes in nanohardness with increasing Si content were found. The morphology observed by FEG-SEM presents non columnar characteristics for thin films with silicon addition. The set of results suggests that Si addition is restricting the columnar growth of ZrN thin films. This conclusion is justified by the fact that Si contributes to increase the ZrN grains nucleation during the sputtering process.

Study of Titanium substrate surfaces coated with hydroxyapatite by magnetron sputtering

Ribeiro, Alexandre Antunes; Oliveira, J. C.; Cavaleiro, A.; Oliveira, Marize Varella De; Balestra, R.M.
Fonte: Instituto Nacional de Tecnologia Publicador: Instituto Nacional de Tecnologia
Tipo: apresentação
EN_US
Relevância na Pesquisa
67.01%
The deposition of hydroxyapatite coatings on titanium via sputtering techniques has been quite studied on commercial dense substrates, for use as a biomaterial. In this work, porous titanium samples produced by powder metallurgy and commercially dense titanium sheet, used as control, were used as substrates, both ASTM F67 grade 2. The coatings were deposited by radio frequency magnetron sputtering using a hydroxyapatite target in argon atmosphere with different deposition times. Samples characterization was performed by Optical Microscopy, Scanning Electron Microscopy/Energy Dispersive Spectroscopy and low-angle X-ray Diffraction. Calcium phosphate coating epositions were obtained on both titanium substrates with structure similar to HA phase. The results indicated the potential of this methodology for titanium substrates with homogeneous hydroxyapatite coatings.; Trabalho apresentado no 57º Congresso Brasileiro de Cerâmica, 5º Congresso Iberoamericano de Cerâmica, ocorrido no período de 19 a 22 de maio de 2013 em Natal, RN, Brasil.