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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
76.53%
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
86.67%
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.

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
86.67%
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
86.62%
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
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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...

AlNxOy thin films deposited by DC reactive magnetron sputtering

Borges, Joel; Vaz, F.; Marques, L.
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
Publicado em //2010 ENG
Relevância na Pesquisa
76.75%
AlNxOy thin films were produced by DC reactive magnetron sputtering, using an atmosphere of argon and a reactive gas mixture of nitrogen and oxygen, for a wide range of partial pressures of reactive gas. During the deposition, the discharge current was kept constant and the discharge parameters were monitored. The deposition rate, chemical composition, morphology, structure and electrical resistivity of the coatings are strongly correlated with discharge parameters. Varying the reactive gas mixture partial pressure, the film properties change gradually from metallic-like films, for low reactive gas partial pressures, to stoichiometric amorphous Al2O3 insulator films, at high pressures. For intermediate reactive gas pressures, sub-stoichiometric AlN x O y films were obtained, with the electrical resistivity of the films increasing with the non metallic/metallic ratio.; FEDER - Program COMPETE - Programa Operacional Factores de Competitividade; Fundação para a Ciência e a Tecnologia (FCT) - Project PTDC/CTM/69362/2006; PhD grant Nº SFRH/BD/47118/2008

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
86.62%
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

Blocking layer effect on dye-sensitized solar cells assembled with TiO2 nanorods prepared by dc reactive magnetron sputtering

Meng Lijian; Li Can
Fonte: American Scientific Publishers Publicador: American Scientific Publishers
Tipo: Artigo de Revista Científica
Publicado em /04/2011 ENG
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Three different thickness dense TiO2 (150 nm, 300 nm and 450 nm respectively) films were deposited on ITO substrates by dc reactive magnetron sputtering technique. These dense TiO2 films were used as the blocking layers. After that, TiO2 nanorod films were deposited on these dense TiO2 films by same technique. Both the dense and nanorod TiO2 films have an anatase phase. The dense TiO2 films have an orientation along the [101] direction and the TiO2 nanorod films show a very strong orientation along the [110] direction. These TiO2 materials were sensitized by N719 dye and the DSSCs were assembled using them as photoelectrode. The effect of the blocking layer on the efficiency of the DSSCs is discussed. The DSSC assembled using TiO2 nanorod film with 300 nm thickness blocking layer shows a high efficiency of 2.07%.

The control of the diameter of the nanorods prepared by dc reactive magnetron sputtering and the applications for DSSC

Meng Lijian; Ren Tong; Li Can
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
Publicado em /03/2010 ENG
Relevância na Pesquisa
76.54%
The TiO2 nanorod arrays, with about 1.8 μm lengths, have been deposited on ITO substrates by dc reactive magnetron sputtering at different target-substrate distances. The average diameter of these nanorods can be modified from about 45 nm to 85 nm by adjusting the target-substrate distance from 90 mm to 50 mm. These nanorods are highly ordered and perpendicular to the substrate. Both XRD and Raman measurements show that the nanorods prepared at different target-substrate distances have only an anatase TiO2 phase. The nanorods prepared at the target-substrate distance less than 80 mm have a preferred orientation along the (220) direction. However, this preferred orientation disappears as the target-substrate distance is more than 80 mm. These TiO2 nanorods have been used as the electrodes for dye-sensitized solar cells (DSSC). The highest conversion efficiency, about 4.78%, has been achieved for TiO2 nanorods prepared at 80 mm target-substrate distance.; SFRH/BSAB/862/2008, FCT, Portugal

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
76.67%
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...

Study of vanadium doped ZnO films prepared by dc reactive magnetron sputtering at different substrate temperatures

Meng Lijian; Teixeira, Vasco M. P.; Santos, M. P. dos
Fonte: American Scientific Publishers Publicador: American Scientific Publishers
Tipo: Artigo de Revista Científica
Publicado em /02/2013 POR
Relevância na Pesquisa
76.54%
ZnO films doped with vanadium (ZnO:V) have been prepared by dc reactive magnetron sputtering technique at different substrate temperatures (RT–500 C). The effects of the substrate temperature on ZnO:V films properties have been studied. XRD measurements show that only ZnO polycrystalline structure has been obtained, no V2O5 or VO2 crystal phase can be observed. It has been found that the film prepared at low substrate temperature has a preferred orientation along the (002) direction. As the substrate temperature is increased, the (002) peak intensity decreases. When the substrate temperature reaches the 500 ºC, the film shows a random orientation. SEM measurements show a clear formation of the nano-grains in the sample surface when the substrate temperature is higher than 400 º C. The optical properties of the films have been studied by measuring the specular transmittance. The refractive index has been calculated by fitting the transmittance spectra using OJL model combined with harmonic oscillator.

Erbium-doped nanocrystalline silicon thin films produced by RF sputtering - Annealing effect on the Er emission

Cerqueira, M.F.; Monteiro, Teresa; Soares, Manuel; Kozanecki, A.; Alpuim, P.; Alves, E.
Fonte: WILEY-VCH Verlag GmbH Publicador: WILEY-VCH Verlag GmbH
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
76.59%
In the present work, erbium doped nanocrystalline silicon thin films were produced by reactive magnetron sputtering on glass substrates under different conditions (substrate temperature and Er content). The film structure was studied using Raman spectroscopy. The chemical composition was determined using the RBS technique. All the samples show sharp 4I13/2 → 4I15/2 intra-4f11 emission of Er 3+ related centres with its maximum positioned at the1.54 μm. However, the intensity of this transition (strongly dependent on the chemical composition of the matrix where the nanocrystals are embedded in and also on the structure of the matrix) changes after thermal annealing treatment. For the less crystalline samples our results show an increase of the Er3+ PL intensity and for the highly crystalline ones the Er emission vanishes even at low temperature. This behaviour was studied and explained in this work, on the basis of energy transfer between Si and Er ions.; Partilhar documento na coleção da comunidade Laboratório Associado I3N

Effect of Annealing Temperature on TiO(2) Nanorod Films Prepared by dc Reactive Magnetron Sputtering for Dye-Sensitized Solar Cells

Meng, LJ; Li, C; dos Santos, MP
Fonte: Publisher: SPRINGER, VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS Source: JOURNAL OF INORGANIC AND ORGANOMETALLIC POLYMERS AND MATERIALS Volume: 21 Issue: 4 Pages: 770-776 DOI: 10.1007/s10904-011-9538-y Published: DEC 2011 Publicador: Publisher: SPRINGER, VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS Source: JOURNAL OF INORGANIC AND ORGANOMETALLIC POLYMERS AND MATERIALS Volume: 21 Issue: 4 Pages: 770-776 DOI: 10.1007/s10904-011-9538-y Published: DEC 2011
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
76.54%
Abstract: Anatase TiO(2) nanorod films have been prepared on ITO coated glass substrates at room temperature by dc reactive magnetron sputtering technique. The nanorods are highly ordered and are perpendicular to the substrate. XRD measurements show that the anatase nanorods have a preferred orientation along the [110] direction. The prepared nanorods were annealed at different temperatures (200-500 A degrees C) in air for 1 h. The dye-sensitized solar cells (DSSC) have been made using the as-deposited and annealed TiO(2) nanorods as working electrodes. It has been found that annealing improves the efficiency of the DSSC. An optimum conversion efficiency of 2.13%, at 100 mW/cm(2) light intensity has been achieved with TiO(2) nanorods annealed at 300 A degrees C.

Study of Vanadium Doped ZnO Films Prepared by dc Reactive Magnetron Sputtering at Different Substrate Temperatures

Meng, Lijian; Teixeira, Vasco; Dos Santos, M.P.
Fonte: American Scientific Publishers Publicador: American Scientific Publishers
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
76.54%
ZnO films doped with vanadium (ZnO:V) have been prepared by dc reactive magnetron sputtering technique at different substrate temperatures (RT–500 C). The effects of the substrate temperature on ZnO:V films properties have been studied. XRD measurements show that only ZnO polycrystalline structure has been obtained, no V2O5 or VO2 crystal phase can be observed. It has been found that the film prepared at low substrate temperature has a preferred orientation along the (002) direction. As the substrate temperature is increased, the (002) peak intensity decreases. When the substrate temperature reaches the 500 C, the film shows a random orientation. SEM measurements show a clear formation of the nano-grains in the sample surface when the substrate temperature is higher than 400 C. The optical properties of the films have been studied by measuring the specular transmittance. The refractive index has been calculated by fitting the transmittance spectra using OJL model combined with harmonic oscillator.

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
86.67%
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.

W-Cr-C-N Nanocomposite Thin-Film Coatings via Reactive Magnetron Sputtering

WALOCK, Michael; ZOU, Yujiao; LAGADRILLERE, Denis; NOUVEAU, Corinne; STANISHEVSKY, Andrei
Fonte: Society of Vacuum Coaters Publicador: Society of Vacuum Coaters
EN_US
Relevância na Pesquisa
76.67%
While binary tungsten carbide can form smooth, hard films, these suffer from low fracture toughness. Tungsten nitride films are frequently harder, but are more brittle. Chromium nitride has excellent wear and oxidation resistance, but films often form with low hardness. Composites of these binary compounds offer a possibility to tailor the material for a desired combination of properties. To this end, we have used reactive RF-magnetron sputtering with Cr and WC targets to form quaternary composites, with nitrogen as the reactive gas. The coatings were deposited on Si, Ti, and steel substrates. The nitrogen partial pressure was varied to investigate the relationship between the film properties and the deposition conditions. Energy dispersive spectroscopy showed changes in the chemical composition as a result of the change in nitrogen partial pressure. X-ray diffraction illuminated the structure as either a solid solution with a B1 NaCl structure, or a nanocomposite with the average crystallite size under 11 nm. Optical interferometer revealed low compressive stresses. And nanoindentation established that the films are hard and adherent.; U.S. National Science Foundation (DMR-0806521) and the Regional Council of Burgundy, France

Silica-based Nano-coating on Zirconia Surfaces Using Reactive Magnetron Sputtering: Effect on Chemical Adhesion of Resin Cements

Cavalcanti Queiroz, Jose Renato; Massi, Marcos; Nogueira, Lafayette; Silva Sobrinho, Argemiro Soares da; Bottino, Marco Antonio; Oezcan, Mutlu
Fonte: Quintessence Publishing Co Inc Publicador: Quintessence Publishing Co Inc
Tipo: Artigo de Revista Científica Formato: 151-159
ENG
Relevância na Pesquisa
96.67%
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Processo FAPESP: 09/53584-4; Purpose: To compare the effect of silica (Si)-based nano-coating deposited by reactive magnetron sputtering (RMP) with that of conventional surface conditioning using metal/zirconia primer alone or after air-particle abrasion on the adhesion of resin cements to zirconia ceramic.Materials and Methods: Two hundred forty zirconia ceramic blocks (Cercon) were sintered, finished with 1200-grit SiC paper under water cooling, and cleaned ultrasonically in distilled water for 10 min. The blocks (4.5 mm x 3.5 mm x 4.5 mm) were randomly divided into 24 groups (n = 10) according to 3 testing parameters: a) resin cements (Multilink, Panavia F, RelyX U100), b) surface conditioning (no conditioning as control group; Metal/Zirconia Primer; air abrasion + Metal/Zirconia Primer; Si-based nanofilm + Monobond s); c) aging (no aging vs thermo cycling at 5 degrees C to 55 degrees C, 6000 cycles). The nanofilm was deposited by direct current using argon/oxygen plasma (8:1 in flux) on the zirconia surface. Resin cements were bonded to zirconia surfaces using polyethylene molds. The shear bond strength (SBS) test was performed using a universal testing machine (1 mm/min)...

Influence of process parameters on the growth of pure-phase anatase and rutile TiO2 thin films deposited by low temperature reactive magnetron sputtering

Toku,H.; Pessoa,R.S.; Maciel,H.S.; Massi,M.; Mengui,U.A.
Fonte: Sociedade Brasileira de Física Publicador: Sociedade Brasileira de Física
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/09/2010 EN
Relevância na Pesquisa
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In this work is investigated the optimal conditions for deposition of pure- phase anatase and rutile thin films prepared at low temperatures (less than 150ºC) by reactive dc magnetron sputtering onto well- cleaned p- type Si substrates. For this, the variation of deposition plasma parameters as substrate- to- target distance, total gas pressure, oxygen concentration, and substrate bias were studied and correlated with the characteristics of the deposited films. The XRD analysis indicates the formation of pure rutile phase when the substrate is biased at voltages between - 200 and - 300 V. Pure anatase phase is only attained when the total pressure is higher than 0.7 Pa. Moreover, it's noticeable a strong dependence of surface roughness with parameters studied.

Elaboration of nitride thin films by reactive sputtering

Jouan,Pierre Yves; Tricoteaux,Arnaud; Horny,Nicolas
Fonte: Escola de Minas Publicador: Escola de Minas
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2006 EN
Relevância na Pesquisa
76.7%
The aim of this paper is first a better understanding of DC reactive magnetron sputtering and its implications, such as the hysteresis effect and the process instability. In a second part, this article is devoted to an example of specific application: Aluminium Nitride. AlN thin films have been deposited by reactive triode sputtering. We have studied the effect of the nitrogen contents in the discharge and the RF bias voltage on the growth of AlN films on Si(100) deposited by triode sputtering. Stoichiometry and crystal orientation of AlN films have been characterized by means of Fourier-transform infrared spectroscopy, X-ray diffraction and secondary electron microscopy. Dense and transparent AlN layers were obtained at high deposition rates. These films have a (002) orientation whatever the nitrogen content in the discharge, but the best crystallised ones are obtained at low value (10%). A linear relationship was observed between the AlN lattice parameter "c" (perpendicular to the substrate surface) and the in-plane compressive stress. Applying an RF bias to the substrate leads to a (100) texture, and films become amorphous. Moreover, the film's compressive stress increases up to a value of 8GPa before decreasing slowly as the bias voltage increases.

Characterization of ALN thin films deposited by DC reactive magnetron sputtering

García-Méndez,M.; Morales-Rodríguez,S.; Machorro,R.; De La Cruz,W.
Fonte: Sociedad Mexicana de Física Publicador: Sociedad Mexicana de Física
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/2008 EN
Relevância na Pesquisa
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A set of AlN thin-films was prepared by reactive magnetron sputtering at room temperature. The purpose of this work was to study the effect of oxygen impurities on the structural and optical properties of AlN films. The structural and optical properties of the resulting films were characterized using X-ray diffraction (XRD) and spectroscopic ellipsometry, respectively. Depending on the deposition conditions, films can be hexagonal (wurtzite, P6(3)3m3) or cubic (zinc blende, Fm3m) in their microstructure. From the optical measurements, the ellipsometric parameters (ψ,Δ) and the real refractive index as a function of energy were obtained. From the ellipsometric measurements, a model of the Lorentz single-oscillator was employed to estimate the optical band gap, Eg.