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Efeito do tratamento a plasma do politetrafluoroetileno (PTFE) nas suas propriedades eletrostáticas e superficiais

Pomin, Edison
Fonte: Universidade Estadual Paulista (UNESP) Publicador: Universidade Estadual Paulista (UNESP)
Tipo: Dissertação de Mestrado Formato: 136 f. : il.
POR
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26.68%
Pós-graduação em Ciência e Tecnologia de Materiais - FC; Nestre trabalho, Polietrafluroetileno (PTFE) foi tratado por três técnicas: (1) exposição a plasma com gases não polimerizáveis (Ar, He, H2, O2, e N2), num reator a plasma com arranjo capacitivo dos eletrodos, excitado por radiofrequencia (rf);(2) ablação em eletrodo de cobre excitado por rf, com subsequente implantação iônica e deposição por imersão em plasma (IIDIP); e (3) rf-magnetron sputterring associado com IIDIP. Investigaram-se os efeitos dos tratamento nas propriedades superficiais e elétricas do substrato. O objetivo foi reduzir a capacidade do PTFE à acumulação de cargas elétricas. As alterações de molhabilidade e energia de superfície foram obtidas por medida do ângulo de contato. A espessura e a rugosidade foram medidas por perfilometria e microscopia de força atômica (AFM). A estrutura e composição química da superfície foram analisadas por espectroscopia no infravermelho por tranformada de Fourier (FTIR) e espectroscopia de fotoelétrons de raios-X (XPS). A resistividade elétrica superficial foi medida através de eletrômetro pelo método dos dois pontos. As caracterizações demonstraram que a técnica (1) foi capaz de alterar as características superficiais do substrato em muitos aspectos...

Preparation and characterization of optical multilayered coatings for smart windows applications; Preparação e caracterização de revestimentos ópticos multicamada para aplicações em janelas inteligentes

Cui, Hai-Ning
Fonte: Universidade do Minho Publicador: Universidade do Minho
Tipo: Tese de Doutorado
Publicado em //2005 ENG
Relevância na Pesquisa
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Tese de doutoramento em Ciências.; Multilayer films with a tungsten oxide (WO3) layer were deposited by reactive dc magnetron sputtering onto glass substrates for electrochromic (EC) applications. The configuration of the smart EC devices (ECDs) or window is ITO (Indium-tin-oxide)/WO3/Li+electrolyte/counter electrode film/ITO. Depending on the choice of different counter electrodes such as SnO2, V2O5, ZrO2 and the doped Mo (or Fe) films, a total of 15 different window structures were fabricated and studied. The multilayer ECD between two pieces of glass exhibited maximum optical transmittance of 84 % and minimum of 16 % before and after applying 5 V voltages. The change from bleached to coloured state takes two seconds in visible light range, counter to operation it takes 5 seconds. Without glass substrate the multilayer exhibited a maximum of 97 % transmittance at bleached state. The discussion of the structural model based on hexagonal WO3, in which three- and sixmembered rings of octahedra are displayed, exhibits suitable kinetic behaviour of ions insertion / extraction functions. The tunnel size data for transition of ions in different structures of the WO3 film are deduced and given. A forced intercalation model was proposed to explain some EC phenomenon such as no reversibility...

SiC formation for a solar cell passivation layer using an RF magnetron co-sputtering system

Joung, Yeun-Ho; Kang, Hyun Il; Kim, Jung Hyun; Lee, Hae-Seok; Lee, Jaehyung; Choi, Won Seok
Fonte: Springer Publicador: Springer
Tipo: Artigo de Revista Científica
Publicado em 05/01/2012 EN
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In this paper, we describe a method of amorphous silicon carbide film formation for a solar cell passivation layer. The film was deposited on p-type silicon (100) and glass substrates by an RF magnetron co-sputtering system using a Si target and a C target at a room-temperature condition. Several different SiC [Si1-xCx] film compositions were achieved by controlling the Si target power with a fixed C target power at 150 W. Then, structural, optical, and electrical properties of the Si1-xCx films were studied. The structural properties were investigated by transmission electron microscopy and secondary ion mass spectrometry. The optical properties were achieved by UV-visible spectroscopy and ellipsometry. The performance of Si1-xCx passivation was explored by carrier lifetime measurement.

ZnO:Al Thin Film Gas Sensor for Detection of Ethanol Vapor

Chou, Shih Min; Teoh, Lay Gaik; Lai, Wei Hao; Su, Yen Hsun; Hon, Min Hsiung
Fonte: Molecular Diversity Preservation International (MDPI) Publicador: Molecular Diversity Preservation International (MDPI)
Tipo: Artigo de Revista Científica
Publicado em 30/10/2006 EN
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The ZnO:Al thin films were prepared by RF magnetron sputtering on Si substrate using Pt as interdigitated electrodes. The structure was characterized by XRD and SEM analyses, and the ethanol vapor gas sensing as well as electrical properties have been investigated and discussed. The gas sensing results show that the sensitivity for detecting 400 ppm ethanol vapor was ∼20 at an operating temperature of 250°C. The high sensitivity, fast recovery, and reliability suggest that ZnO:Al thin film prepared by RF magnetron sputtering can be used for ethanol vapor gas sensing.

Optical properties of nanostructured silicon-rich silicon dioxide; Optical properties of nanostructured SRO

Stolfi, Michael Anthony
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 195 p.
ENG
Relevância na Pesquisa
26.64%
We have conducted a study of the optical properties of sputtered silicon-rich silicon dioxide (SRO) thin films with specific application for the fabrication of erbium-doped waveguide amplifiers and lasers, polarization sensitive devices and devices to modify the polarization state of light. The SRO thin films were prepared through a reactive RF magnetron sputtering from a Si target in an O2/Ar gas mixture. The film stoichiometry was controlled by varying the power applied to the Si target or changing the percentage of 02 in the gas mixture. A deposition model is presented which incorporates the physical and chemical aspects of the sputtering process to predict the film stoichiometry and deposition rate for variable deposition conditions. The as-deposited films are optically anisotropic with a positive birefringence (nTM > nTE) that increases with increasing silicon content for as-deposited films. The dependence of the birefringence on annealing temperature is also influenced by the silicon content. After annealing, samples with high silicon content (>45 at%) showed birefringence enhancement while samples with low silicon content (<45 at%) showed birefringence reduction. A birefringence of more than 3% can be generated in films with high silicon content (50 at% Si) annealed at 11000C.; (cont.) We attribute the birefringence to the columnar film morphology achieved through our sputtering conditions. Er was incorporated through reactive co-sputtering from Er and Si targets in the same O2/Ar atmosphere in order to investigate the energy-transfer process between SRO and Er for low annealing temperatures. By studying the photoluminescence (PL) intensity of Er:SRO samples annealed in a wide range of temperatures...

Desenvolvimento e caracterização de dispositivos para reposição de filmes finos por descarga em cátodo oco

Araújo, Francisco Odolberto de
Fonte: Universidade Federal do Rio Grande do Norte; BR; UFRN; Programa de Pós-Graduação em Física; Física da Matéria Condensada; Astrofísica e Cosmologia; Física da Ionosfera Publicador: Universidade Federal do Rio Grande do Norte; BR; UFRN; Programa de Pós-Graduação em Física; Física da Matéria Condensada; Astrofísica e Cosmologia; Física da Ionosfera
Tipo: Tese de Doutorado Formato: application/pdf
POR
Relevância na Pesquisa
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In the present work we use a plasma jet system with a hollow cathode to deposit thin TiO2 films on silicon substrates as alternative at sol-gel, PECVD, dip-coating e magnetron sputtering techniques. The cylindrical cathode, made from pure titanium, can be negatively polarized between 0 e 1200 V and supports an electrical current of up to 1 A. An Ar/O2 mixture, with a total flux of 20 sccm and an O2 percentage ranging between 0 and 30%, is passed through a cylindrical hole machined in the cathode. The plasma parameters and your influence on the properties of deposited TiO2 films and their deposition rate was studied. When discharge occurs, titanium atoms are sputtered/evaporated. They are transported by the jet and deposited on the Si substrates located on the substrate holder facing the plasma jet system at a distance ranging between10 and 50 mm from the cathode. The working pressure was 10-3 mbar and the deposition time was 10 -60 min. Deposited films were characterized by scanning electron microscopy and atomic force microscopy to check the film uniformity and morphology and by X-ray diffraction to analyze qualitatively the phases present. Also it is presented the new dispositive denominate ionizing cage, derived from the active screen plasma nitriding (ASPN)...

Anisotropia magnética (110) em Nanofilmes de Permalloy sobre MgO(100)

Medeiros, Anna Cecília Dantas de
Fonte: Universidade Federal do Rio Grande do Norte; BR; UFRN; Programa de Pós-Graduação em Física; Física da Matéria Condensada; Astrofísica e Cosmologia; Física da Ionosfera Publicador: Universidade Federal do Rio Grande do Norte; BR; UFRN; Programa de Pós-Graduação em Física; Física da Matéria Condensada; Astrofísica e Cosmologia; Física da Ionosfera
Tipo: Dissertação Formato: application/pdf
POR
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The study and fabrication of nanostructured systems composed of magnetic materials has been an area of great scientific and technological interest. Soft magnetic materials, in particular, have had great importance in the development of magnetic devices. Among such materials we highlight the use of alloys of Ni and Fe, known as Permalloy. We present measurement results of structural characterization and magnetic films in Permalloy (Ni81Fe19), known to be a material with high magnetic permeability, low coercivity and small magneto- crystalline anisotropy, deposited on MgO (100) substrates. The Magnetron Sputtering technique was used to obtain the samples with thicknesses varying between 9 150 nm. The techniques of X- ray Diffraction at high and low angle were employed to confirm the crystallographic orientation and thickness of the films. In order to investigate the magnetic properties of the films the techniques of Vibrant Sample Magnetometry (VSM), Ferromagnetic Resonance (FMR) and Magnetoimpedance were used. The magnetization curves revealed the presence of anisotropy for the films of Py/MgO (100), where it was found that there are three distinct axis - an easy-axis for θH = 0°, a hard-axis for θH = 45° and an intermediate for θH = 90°. The results of the FMR and Magnetoimpedance techniques confirm that there are three distinct axes...

Estudo por ressonância ferromagnética das anisotropias uniaxial e unidirecional em bicamadas e tricamadas magnéticas; Ferromagnetic resonance study of the anisotropies uniaxial and unidirectional magnetic bilayer and tricamadas

Sousa, Marcos Antonio de
Fonte: Universidade Federal de Goiás; BR; UFG; Mestrado em Física; Ciências Exatas e da Terra Publicador: Universidade Federal de Goiás; BR; UFG; Mestrado em Física; Ciências Exatas e da Terra
Tipo: Dissertação Formato: application/pdf
POR
Relevância na Pesquisa
26.69%
The Ferromagnetic Resonance (FMR) technique at the X-band (~ 9.70 GHz) and Q-band (~ 34.0 GHz) was used to study the magnetic properties of NiO/Co, NiO/Py and Py/FeMn bilayers, and Co/NiO/Co trilayers with different thicknesses, deposited by dc magnetron sputtering technique in the presence of a 400 Oe magnetic field. The FMR experiments were all done at room temperature using a high sensitivity Bruker ESP-300 spectrometer, with static scanning field and usual modulation and phase sensitive detection techniques. The angular dependence of the inplane resonance field allows the measurement of the exchange bias field for some NiO/Py bilayers and the uniaxial anisotropy of the Co layer of NiO/Py bilayers and Co/NiO/Co trilayers. The value of the exchange bias field of the NiO/Py bilayers varies from 29 Oe to 123 Oe while the uniaxial anisotropy field of the Co layer, varies from 5 to 45 Oe. For Co/NiO/Co trilayers, the Co in-plane uniaxial anisotropy field varies from 34 to 216 Oe. The out-of-plane angular dependence of the resonance field allows the measurement of the effective magnetization and the g-factor, which depend not only on the specific parameters of the samples, such as thickness of the ferromagnetic layer, but also on the deposition conditions. The results obtained were compared with known values in the literature and show the high sensitivity of the ferromagnetic resonance technique in the study of the magnetic anisotropy and the exchange bias phenomena.; A técnica de ressonância ferromagnética (FMR) foi utilizada para estudar propriedades magnéticas de bicamadas NiO/Co...

Produ??o de superf?cies seletivas de Ni/NiO para aplica??es em coletores solares

Sade, Wagner
Fonte: Programa de P?s-Gradua??o em Engenharia de Materiais. Rede Tem?tica em Engenharia de Materiais, Pr?-Reitoria de Pesquisa e P?s-Gradua??o, Universidade Federal de Ouro Preto. Publicador: Programa de P?s-Gradua??o em Engenharia de Materiais. Rede Tem?tica em Engenharia de Materiais, Pr?-Reitoria de Pesquisa e P?s-Gradua??o, Universidade Federal de Ouro Preto.
Tipo: Tese de Doutorado
PT_BR
Relevância na Pesquisa
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Novas tecnologias e novos materiais v?m sendo desenvolvidos a fim de tornar a tecnologia solar economicamente mais atrativa. Materiais como o n?quel (Ni) e o ?xido de n?quel (NiO) depositados sobre alum?nio t?m-se destacado em v?rias aplica??es fotot?rmicas atuando como superf?cies seletivas para a faixa do espectro solar. As superf?cies seletivas s?o as placas absorvedoras de calor dos coletores solares. Neste trabalho foram produzidos filmes finos de Ni/NiO em substrato de alum?nio por processos qu?micos e eletrol?ticos seguidos de oxida??o e por deposi??o f?sica, magnetron sputtering. A deposi??o qu?mica com posterior oxida??o consistiu na inova??o desse projeto. Assim, foram obtidas superf?cies seletivas com alta absort?ncia solar, maior que 85%, e baixa emit?ncia t?rmica, menor que 15%, a fim de se aquecer ?gua para fins sanit?rios, secagem de gr?os, al?m de diversas aplica??es nas ind?strias t?xteis e qu?micas com uma melhor rela??o custo-benef?cio. O fator de seletividade destas superf?cies foi maior que 6, o que as caracterizaram como moderamente e altamente seletivas. A composi??o qu?mica dos filmes de Ni/NiO foi determinada por espectroscopia de emiss?o ?ptica por centelhamento. As espessuras foram medidas por microscopia de for?a at?mica e por perfilometria...

Processing and characterization of lithium niobate thin films for ferroelectric nonvolatile memory applications

Zhu, Jie
Fonte: Universidade Rice Publicador: Universidade Rice
ENG
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Both highly c-axis and randomly-oriented LiNbO3 thin films are grown on p-type Si (111) substrates by RF magnetron sputtering and metallo-organic decomposition (MOD), respectively. Ellipsometry, X-ray diffraction, AFM and SEM are used to analyze the structural quality of the deposited ferroelectric thin films, including thickness, crystallinity, stoichiometry and surface roughness. Metal-ferroelectric-semiconductor structures are fabricated and electrically characterized with polarization vs. electric field (P-E) and capacitance vs. voltage (C-V) measurements. Hysteresis curves based on polarization switching are observed, verifying the ferroelectricity of deposited LiNbO3 thin films. Comparison of different film growth mechanisms between these two deposition methods is made, and their effects on physical and electrical characteristics of the derived LiNbO3 thin films are discussed. RF magnetron sputtering is proved to be a more promising thin-film growth technique than MOD for ferroelectric nonvolatile memory applications.

Surface Modification of Molds and Acessories for the Glass Industry

Fernandes, Filipe
Fonte: Universidade de Coimbra Publicador: Universidade de Coimbra
Tipo: Tese de Doutorado
ENG
Relevância na Pesquisa
26.69%
Coatings are frequently applied on molds and accessories for the glass industry in order to restrict surface degradation such as oxidation, corrosion, abrasion and wear of the structural material, thereby decreasing the maintenance costs and increasing the lifetime and performance of components. However, in order to obtain accurate lifetime expectancies and performance of the coatings it is necessary to have a complete reliable understanding of their properties. This thesis is on the improvement of the surface properties and integrity of molds, in order to increase their durability, through the application of different types of coatings. Two methodologies were followed to reach such demands: 1 - synthesis, optimization and characterization of coatings currently used in molds surface protection (Ni-based alloys deposited by Plasma Transferred Arc); 2 - synthesis and characterization of new coatings with improved functionalities, deposited by emergent deposition processes such as Atmospheric Plasma Spraying and DC Reactive Magnetron Sputtering. In a first step it was intended to optimize Ni-based coatings deposited by PTA process, studying the effect of substrate dilution on the properties of coatings. In the second part, two different coating systems were evaluated. The first topic investigated the effect of ZrO2 additions on the microstructure...

Preparation of Stabilizer-Free Silver Nanoparticle-Coated Micropipettes as Surface-Enhanced Raman Scattering Substrate for Single Cell Detection

Tan, Yi-bin; Zou, Jie-meng; Gu, Ning
Fonte: Springer US Publicador: Springer US
Tipo: Artigo de Revista Científica
Publicado em 26/10/2015 EN
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In this work, we established a convenient while reproduceable method for stabilizer-free silver nanoparticle (AgNP)-coated micropipettes by the combination of magnetron sputtering and surface coupling agent. The clear surfaces of the AgNPs are beneficial for absorbing biological or functional molecules on their surfaces. By optimizing the operating parameters, such as sputtering current and sputtering time, the tip of micropipettes coated with AgNPs exhibits excellent surface-enhanced Raman scattering (SERS) performance. Finally, the Raman spectra of a single A549 lung adenocarcinoma cell are successfully acquired by these advanced SERS-active micropipettes.

Reactive sputter magnetron reactor for preparation of thin films and simultaneous in situ structural study by X-ray diffraction

Burgi, Juan Mauel; Newenschwander, R.; Kellerman, G.; García Molleja, Javier; Craievich, A.; Feugeas J.
Fonte: Amer Inst Physics Publicador: Amer Inst Physics
Tipo: info:eu-repo/semantics/article; info:ar-repo/semantics/artículo; info:eu-repo/semantics/publishedVersion Formato: application/pdf
ENG
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The purpose of the designed reactor is (i) to obtain polycrystalline and/or amorphous thin films by controlled deposition induced by a reactive sputtering magnetron and (ii) to perform a parallel in situ structural study of the deposited thin films by X-ray diffraction, in real time, during the whole growth process. The designed reactor allows for the control and precise variation of the relevant processing parameters, namely, magnetron target-to-sample distance, dc magnetron voltage, and nature of the gas mixture, gas pressure and temperature of the substrate. On the other hand, the chamber can be used in different X-ray diffraction scanning modes, namely, θ-2θ scanning, fixed α-2θ scanning, and also low angle techniques such as grazing incidence small angle X-ray scattering and X-ray reflectivity. The chamber was mounted on a standard four-circle diffractometer located in a synchrotron beam line and first used for a preliminary X-ray diffraction analysis of AlN thin films during their growth on the surface of a (100) silicon wafer. © 2013 American Institute of Physics; Fil: Burgi, Juan Mauel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - CONICET - Rosario. Instituto de Fisica de Rosario (i); Argentina;; Fil: Newenschwander...

Structure and mechanical properties of TiC films deposited using combination of pulsed DC and normal DC magnetron co-sputtering

Thulasi Raman, K.H.; Mangalampalli, S.R.N. Kiran; Ramamurty, U; Rao, G. Mohan
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
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Titanium-carbon (TiC) thin films of different compositions were prepared by a combination of pulsed DC (for Ti target) and normal DC (for graphite target) magnetron co-sputtering on oxidized silicon and fused quartz substrates. At 33.7 at.% of C content,

Estudo do magnetismo de filmes finos multicamadas baseados em ligas níquel-cobre e antiferromagnetos de anisotropia cúbica; Study of Magnetism in Multilayered Thin Films Based on Nickel-Copper Alloys and Cubic Antiferromagnets

Garanhani, Francisco Jose
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 04/11/2015 PT
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Neste trabalho foram estudadas as propriedades magnéticas e características estruturais de filmes finos bicamadas e multicamadas formados com Ni{x}Cu{1-x} (ferromagneto, 50 x 90 e níquel puro), NiO, FeMn e IrMn (antiferromagnetos). Ligas de níquel-cobre podem ser classificadas como fracamente ferromagnéticas. Ferromagnetismo fraco gera efeitos únicos em propriedades de transporte eletrônico, junções com supercondutores e sistemas de exchange bias. Sendo uma solução sólida extremamente simples, diversas propriedades do NiCu dependem linearmente da estequiometria da liga. Os filmes finos foram depositados via magnetron sputtering em substratos monocristalinos de Si (100) a temperatura ambiente. A estrutura cristalina foi caracterizada por difração de raios-X e a morfologia foi analisada por retroespalhamento Rutherford. Propriedades magnéticas foram medidas com um SQUID a temperaturas entre 5K e 300K (curvas ZFC/FC e de magnetização a diferentes temperaturas) e com um VSM a temperatura ambiente (curvas de magnetização em diferentes ângulos no plano do filme). As amostras com Ni{x}Cu{1-x} mais ricas em cobre apresentam os maiores campos coercivo e de exchange bias a baixas temperaturas, mas os menores em altas temperaturas...

Martensite structures and twinning in substrate-constrained epitaxial Ni-Mn-Ga films deposited by a magnetron co-sputtering process

Tillier, Jérémy; Bourgault, Daniel; Pairis, Sébastien; Ortega, Luc; Caillault, Nathalie; Carbone, Laurent
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 17/01/2011
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In order to obtain Ni-Mn-Ga epitaxial films crystallized in martensite structures showing Magnetic-Induced Rearrangement (MIR) of martensite variants, a fine control of the composition is required. Here we present how the co-sputtering process might be helpful in the development of Ni-Mn-Ga epitaxial films. A batch of epitaxial Ni-Mn-Ga films deposited by co-sputtering of a Ni-Mn-Ga ternary target and a pure manganese target has been studied. The co-sputtering process allows a precise control of the film compositions and enables keeping the epitaxial growth of Ni-Mn-Ga austenite during deposition at high temperature. It gives rise to tune the content of the MIR-active 14-modulated martensite in the film at room temperature, as well as micro and macro-twinned domains sizes.

Integrating Atomic Layer Deposition and Ultra-High Vacuum Physical Vapor Deposition for In Situ Fabrication of Tunnel Junctions

Elliot, Alan J.; Malek, Gary A.; Lu, Rongtao; Han, Siyuan; Yiu, Haifeng; Zhao, Shiping; Wu, Judy Z.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 05/05/2014
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26.64%
Atomic Layer Deposition (ALD) is a promising technique for growing ultrathin, pristine dielectrics on metal substrates, which is essential to many electronic devices. Tunnel junctions are an excellent example which require a leak-free, ultrathin dielectric tunnel barrier of typical thickness around 1 nm between two metal electrodes. A challenge in the development of ultrathin dielectric tunnel barrier using ALD is controlling the nucleation of dielectrics on metals with minimal formation of native oxides at the metal surface for high-quality interfaces between the tunnel barrier and metal electrodes. This poses a critical need for integrating ALD with ultra-high vacuum (UHV) physical vapor deposition. In order to address these challenges, a viscous-flow ALD chamber was designed and interfaced to an UHV magnetron sputtering chamber via a load lock. A sample transportation system was implemented for in situ sample transfer between the ALD, load lock, and sputtering chambers. Using this integrated ALD-UHV sputtering system, superconductor-insulator-superconductor (SIS) Nb/Al/Al2O3/Nb Josephson tunnel junctions were fabricated with tunnel barriers of thickness varied from sub-nm to ~ 1 nm. The suitability of using an Al wetting layer for initiation of the ALD Al2O3 tunnel barrier was investigated with ellipsometry...

Film Coating Process Research and Characterization of TiN Coated Racetrack-type Ceramic Pipe

Wang, Jie; Xu, Yanhui; Zhang, Bo; Wei, Wei; Fan, Le; Pei, Xiangtao; Hong, Yuanzhi; Wang, Yong
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 12/01/2015
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TiN film was coated on the internal face of racetrack-type ceramic pipe by three different methods: radio-frequency sputtering, DC sputtering and DC magnetron sputtering. The deposition rates of TiN film under different coating methods were compared. According to the AFM, SEM, XPS test results,these properties were analyzed, such as TiN film roughness and surface morphology. At the same time, the deposition rates were studied under two types' cathode, Ti wires and Ti plate. According to the SEM test results, Ti plate cathode can improve the TiN/Ti film deposition rate obviously.

Interface-dominated Growth of a Metastable Novel Alloy Phase

Sarkar, Subhendu; Datta, Alokmay; Chakraborty, Purushottam; Satpati, Biswarup
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 17/06/2005
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A new \textit{D0$_{23}$} metastable phase of Cu$_3$Au is found to grow at the interfaces of Au/Cu multilayers deposited by magnetron sputtering. The extent of formation of this novel alloy phase depends upon an optimal range of interfacial width primarily governed by the deposition wattage of the dc-magnetron used. Such interfacially confined growth is utilized to grow a $\sim$ 300 nm thick Au/Cu multilayer with thickness of each layer nearly equal to the optimal interfacial width which was obtained from secondary ion mass spectrometry (SIMS) data. This growth technique is observed to enhance the formation of the novel alloy phase to a considerable extent. SIMS depth profile also indicates that the mass fragment corresponding to Cu$_3$Au occupies the whole film while x-ray diffraction (XRD) shows almost all the strong peaks belonging to the \textit{D0$_{23}$} structure. High resolution cross-sectional transmission electron microscopy (HR-XTEM) shows the near perfect growth of the individual layers and also the lattice image of the alloy phase in the interfacial region. Vacuum annealing of the alloy film and XRD studies indicate stabilization of the \textit{D0$_{23}$} phase at $\sim$ 150$^{\circ}$C. The role of interfacial confinement...

Propiedades mecánicas de nitruros metálicos depositados con UBM: tecnología eficiente y ambientalmente limpia

Olaya,J.J.; Marulanda,D.M.; Rodil,S.E.; Bhushan,B.
Fonte: Sociedad Mexicana de Física Publicador: Sociedad Mexicana de Física
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2009 ES
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El objetivo de esta investigación es estudiar la influencia de la configuración del campo magnético en un sistema de sputtering en las propiedades mecánicas de recubrimientos de CrN, TaN, TiN, NbN y ZrN. Se cuantificaron diferentes configuraciones del campo magnético a través del coeficiente de desbalanceo K G , que es proporcional al punto de campo cero en el magnetrón. En este trabajo de depositaron películas con dos configuraciones del campo magnético, K G =1.3 y 0.825. El efecto más importante de la configuración del campo magnético se observó en la dureza de la película. Al depositar sobre acero AISI M2 y acero 304, mejoraron las propiedades mecánicas y la resistencia al desgaste al aumentar el parámetro de energía; los valores de dureza más altos se obtuvieron para las películas de TaN, NbN y ZrN. Otra consecuencia del cambio en el campo magnético fue la variación en los esfuerzos residuales de compresión. La variación más alta se presentó en las películas de TaN mientras que las películas de CrN presentaron la menor concentración de esfuerzos.