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In the work of the various parameters studied film amorphous and nano-crystalline alloy silicon-carbon (а-nc-Si1-xCx :H (x=0÷1)) doped with phosphorus (PH3 ) and boron (B2 H6 ). Studied the properties of these films on different substrates derived from quartz, glass and Silicon-coated Fe, Al, Pd, Ni, Ti, Ag. Using transmission electron microscopy (TEM) studied the morphology obtained nano tubes. Also examine the structural properties of films by using infrared spectroscopy and x-ray diffraction of x-rays. Created by cascade solar cells area S = 1.2 cm2 and have a coefficient of 11.2%.

Structural properties of TiO2 thin films play a main role in determine the characteristic of the thin films especially their stability and activity, the total pressure has a great influence in determine the crystallinity of the films and the orientation of the facets of their structure, especially the two facet (101) and (001), the enhancing the structure properties will cause to enhance the application efficiency of TiO2 thin films such as the dissociative adsorption of water and the solar cell. Many researcher interest to prepare the TiO2 thin film under the low range of total pressure (less than to 10 Pa) to avoid the low degree of crystalline and the mixed of two phase anatas and rutile, so in our work tend to prepare TiO2 thin films under a high total pressure (more than 10 Pa) with values (10, 20, 50 and 100) Pa and with (1:1) mixed ratio of Argon and Oxygen gases, the pattern of X-Ray diffraction revealed that the structure was polycrystalline and the phase was anatas. The intensity at 2θ ≈ 25.00°, 37.00°, 53.00° and 55.00° correspond to the diffraction from (101), (004), (105) and (211) planes respectively. The intensity and number of peaks decreased with increased the total pressure, the plane (101) could be considered as a prefential growth plane which take a high texture factor and this would decreased with increased the total pressure, the ratio of texture factor between 001 and 101 will increase with decrease the total pressure, The lattice constant and the interplanar distance displayed a greater deviation compared with the standard value at the lowest total pressure than the decrease observed with increased total pressure.

In this work, TiO2/Cu2O heterostructures were obtained in a two-step process with a direct current magnetron sputtering method. We studied the morphological properties and composition of the thin films by scanning electron microscopy. Optical properties and energy bands at the heterojunction were recorded using a spectrophotometer. Additionally, the current–voltage characteristics examined in both total darkness and with illumination were estimated to have an irradiation (radiation flux divided by area) of 1000 W/m2.

The electrochemical and gravimetric methods were used to study the effect of nitrogen using in the reaction mixture during magnetron deposition on the Ti-O-N films corrosion-electrochemical behavior. Polarization studies of the films electrochemical dissolution in aque-ous solution of 3 % NaCl in a potentiostatic mode are presented. It was found that upon dis-solution of the films, passivation, activation, and passivation of the coating surface are ob-served, associated with the formation of oxide films and titanium chlorides on the sample sur-face. It has been proved that thin films obtained with a high nitrogen content exhibit higher corrosion resistance. In this work, the following corrosion parameters were calculated: mass, depth and current indicators.

International audience; In this study, the influence of the degree of crystallization and thickness of films was correlated with the photoelectrochemical performance of SrTaO2N semiconductor films for O2 evolution reaction under visible light irradiation. Oxynitride films were deposited on various substrates using the sputtering in Ar + N2 reactive atmosphere from a home-made SrTaO2N target. Films with stoichiometric composition were obtained at a high temperature (TS =800 °C) with reduced bandgap. The different substrates led to diverse degrees of film crystallization, from weakly crystallized to fully c-axis oriented. The photoelectrochemical performance was improved by improving the film crystallinity and the thickness. For further improvement of the photoelectrochemical performance, the following three limiting factors are identified 1) low absorption coefficient, especially in the visible domain from 500 to 600 nm; 2) short lifetimes of excited charge carriers; and 3) permittivity with only moderate values lower than 10 in the visible-light domain.

In this work, the dc reactive magnetron sputtering technique was used to prepare and deposit nanostructured titanium dioxide (TiO2) thin films on glass substrates. Titanium dioxide thin films of mixed phase (anatase + rutile) and single phase (anatase) were prepared using different gas mixing ratios, and for both of the two phases, they were diagnosed via x-ray diffraction (XRD). It was found that the contents of rutile in mixed phase dependent on the deposition time increased from the ratio of 40% to 46% and 50% as the deposition time increased from 3 hours to 3.30 and 4 hours. The photocatalytic activity of the mixed and single phase TiO2 was measured by kill the bacteria Escherichia coli (E.Coli) under exposure to UV-radiation. It was proven that the photocatalytic activity in the mixed phase (TiO2) gave better results weight fraction is 40% as an antibacterial activity. Based on the obtained results anti-bacterial activity of dioxide titanium nanoparticles was dependent on the concentration and phase of TiO2 and weight fraction of mixed-phase.

YH2 (111) epitaxial thin films with two and four rotational crystal domains were directly grown both on CaF2 (111) and (001) substrates, respectively, at various growth temperature by reactive magn...

In this paper, a series of TaCN composite films with different carbon content were deposited by the magnetron sputtering system and the microstructure, mechanical and tribological properties were investigated. The results showed that the deposited TaCN films exhibited a three-phase of face-centered cubic (fcc) Ta(C,N), hexagonal closed-packed (hcp) Ta(C,N) and amorphous CNx. With the increase of carbon content, the hardness of the TaCN films first increased and then decreased, after reaching a maximum of 33.1 GPa; the adhesion strength increased gradually; the coefficient of friction decreased monotonically and the wear property initially improved and then weakened at room temperature. The coefficient of friction of the TaCN film at 28.21 at.% carbon decreased first, then increased and then decreased again and its high-temperature wear rate first decreased slightly and then increased, as the temperature increased from room temperature (RT) to 600 °C. The TaCN film at 28.21 at.% carbon exhibited excellent an elevated-temperature tribological properties.

The interaction of thin Ti–B–N films obtained by magnetron reactive sputtering of a TiB2 target was studied in an atmosphere of a gas argon–nitrogen mixture (85 vol % Ar + 15 vol % N2), with mineral acids (HCl, H2SO4, H3PO4, HNO3). It was found that the hexagonal boron nitride formed during the deposition process, along with titanium nitride, forms a resistant protective film that protects the bulk (~85%) of the film from corrosion.

Ti–Al–Mo–N composite films with different molybdenum content were deposited by reactive magnetron sputtering. The results showed that the films consisted of fcc-(Ti, Al, Mo) N substitutional solid ...

We report the irradiation effects on rf reactive magnetron sputter deposited TiO2/Al2O3 hetero-structured thin films. These films are irradiated with 6 MeV electron beams by maintaining the dose ra...

The paper focuses on providing an insight into the current state of computational modeling regarding reactive magnetron sputtering systems. A detailed compilation of developed models is gathered and grouped into categories based on the phenomena being modeled. The survey covers models developed for the analysis of magnetron discharges, particle-surface interactions at the target and the substrate, as well as macroscopic models. Corresponding software packages available online are also presented. After gaining the necessary insight into the current state of research, a list of the most challenging tasks is given, comparing diffierent approaches, that have been used to combat the encountered difficulties. The challenges associated with modeling tasks range from analytical complexity, mathematical know-how used for model approximation and reduction, as well as optimization between computational load and result accuracy. As a conclusion, the future challenges are compiled into a list and a probable direction in modeling is given, that is likely to be further pursued.

In this work, spinel ferrites (NiCoFe2O4) were prepared as thin films by dc reactive dual-magnetron co-sputtering technique. Effects of some operation parameters, such as inter-electrode distance, and preparation conditions such as mixing ratio of argon and oxygen in the gas mixture, on the structural and spectroscopic characteristics of the prepared samples were studied. For samples prepared at inter-electrode distance of 5 cm, only one functional group of OH- was observed in the FTIR spectra as all bands belonging to the metal-oxygen vibration were observed. Similarly, the XRD results showed that decreasing the pressure of oxygen in the gas mixture lead to grow more crystal planes in the samples prepared at inter-electrode distance of 5 cm. The energy band gap was determined for the sample prepared with mixing ratio of 65:35 and found to be 2.7, 2 and 3.35 eV for direct allowed, direct forbidden and indirect allowed transitions, respectively. The high structural purity was confirmed as no traces for any elements other than Co, Ni, Fe and O were found in the final samples.

Rare-earth (RE) oxyhydride thin films prepared by reactive magnetron sputtering followed by air-oxidation show a color-neutral photochromic effect at ambient conditions within a wide composition range (REOxH3-2x where 0.5 ≤ x < 1.5). Due to the high degree of anion sublattice disorder present in these thin films, the structure models proposed for the related bulk materials are not directly applicable. Instead we use a combination of EXAFS analysis and lattice energy calculations to establish a fcc-based model linking the oxyhydrides to the related binary compounds. The oxide anions are found to occupy predominantly the tetrahedral sites in the fcc structure, which is attributed to electrostatic lattice energy minimization.

Zirconium nitride thin films deposited by reactive magnetron sputtering recurrently present small amounts of hafnium (~1 at.%) in their composition derived from an inherent impurity existing in Zr targets. Hf presence in ZrN coatings is neglected by most of the researchers despite its known potential to modify properties of thin films. In this work, pure ZrN (0.9 at.% Hf contaminant) and ZrHfN thin films with intentional hafnium addition of 1.8, 3.7 and 5.5 at.% were deposited by reactive magnetron sputtering and characterized by RBS, GAXRD, SEM, nanohardness and high temperature oxidation tests. Based on the results, it is suggested that inherent hafnium presence in zirconium targets contributes for the good hardness values and oxidation resistance at 773 K registered for ZrN thin films.

Zinc-iridium oxide (Zn-Ir-O) thin films have been demonstrated as a p-type conducting material. However, the stability of p-type conductivity with respect to chemical composition or temperature is still unclear. In this study we discuss the local atomic structure and the electrical properties of Zn-Ir-O films in the large Ir concentration range. The films are deposited by reactive DC magnetron co-sputtering at two different substrate temperatures-without intentional heating and at 300 {\deg}C. Extended X-ray absorption fine structure (EXAFS) analysis reveals that strongly disordered ZnO4 tetrahedra are the main Zn complexes in Zn-Ir-O films with up to 67.4 at% Ir. As the Ir concentration increases, an effective increase of Ir oxidation state is observed. Reverse Monte Carlo analysis of EXAFS at Zn K-edge shows that the average Zn-O interatomic distance and disorder factor increase with the Ir concentration. We observed that the nano-crystalline w-ZnO structure is preserved in a wider Ir concentration range if the substrate is heated during deposition. At low Ir concentration, the transition from n- to p-type conductivity is observed regardless of the temperature of the substrates. Electrical resistivity decreases exponentially with the Ir concentration in the Zn-Ir-O films.

Cuprous oxide (Cu2O) has attracted much attention as a photocatalytic material. In this paper, the mid-frequency reactive magnetron sputtering method was used to prepare Cu2O films on glass slides, and the effects of oxygen flow and deposition time on the structures, morphologies and photocatalytic properties of the films were studied. The results show that the films prepared by this method have smooth surfaces and good absorptivity in the visible region. As the oxygen flow increases, the films transit from the mixed-phase of Cu and Cu2O to the single-phase of Cu2O. When the oxygen flow continues to increase, the films change to a mixed-phase of Cu4O3 and Cu2O. The photocatalytic decolorization of methyl orange under visible light irradiation conditions was used to assess the photocatalytic properties of the prepared films. When the oxygen flow is 6[Formula: see text]sccm and the deposition time is 15[Formula: see text]min, the film exhibits the best photocatalytic activity. Finally, the Mulliken electronegativity theory was used to explain the photocatalytic mechanism of Cu2O. This study confirmed the feasibility of preparing Cu2O photocatalytic films by magnetron sputtering, and provided the experimental basis for the subsequent study of Cu2O photocatalytic films.

TiN films with various nitrogen content were deposited using reactive magnetron sputtering system and the influence of TiN film’s microstructure on thermal diffusivity was investigated. The results...

TaO film @ Pt-decorated glass was deposited through the reactive magnetron sputtering using pure tantalum and oxygen integrated Ar environment. The film properties were studied through XRD, FE-SEM ...

International audience; The composition and structure properties of the CrOxNy films deposited by RF reactive magnetron sputtering were investigated and correlated with their optical properties. Two kinds of targets Cr2O3 and CrN compounds with variation of N2 and O2 gas flow were used to prepare two series of samples. The phase structure, chemical composition and optical properties of CrOxNy films were characterized by X-ray diffraction, X-ray photoelectron spectroscopy and ultraviolet-visible-near-infrared spectrophotometer, respectively. The films mainly consist of Cr2N and CrO3 phases. The Cr/ON ratio derived by XPS varies with the variation of nitrogen with Cr2O3 target. But only lower nitrogen content is detected with variation of oxygen using CrN target. TheCrOxNyy films with higher nitrogen content possess high absorbance around at 35% in the visible light range no matter the target.

Poly(tetrafluoroethylene) (Teflon) has been selected as the self-template structural material in the preparation of VO2 films using a reactive magnetron sputtering method and post-annealing process...

Stainless steel (SS) are extensively used for healthcare, hygiene and surgical applications due to their excellent corrosion resistance and adequate mechanical strength. Among this class SS 316 L i...

The CrN ceramic thin films were deposited using DC reactive magnetron sputtering system on silicon wafer substrate. Oxidation behavior was carried out in air at evaluated temperatures ranging from 500 °C up to 900 °C for 2 h. The structure and element composition of the films at different thermal annealing temperatures ranging were investigated by X-ray diffraction (XRD), Field Emission Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray Spectroscopy (EDS), respectively. The oxidation activation energies of the films were calculated using Arrhenius equation. The changes in the crystal structure from CrN to Cr2O3 phase were investigated from XRD results. The accumulation of grains on surface was confirmed by FESEM micrographs. The cross-section analysis showed an apparent columnar feature with dense structure for the film annealed at low temperature, and becomes porous when increasing the annealing temperature. The thickness was increased from 1.43 to 2.67 μm. The EDS studies indicated the existence of Cr, N and O with different elements compositions on the deposited thin films. The oxidation activation energy for the CrN thin films is 124.4 kJ/mol.

The evolution of the elemental composition, surface morphology, microstructure, and mechanical properties of Ti1 –x–yAlxTаyN coatings deposited by reactive magnetron sputtering has been studied when the ratio of the partial pressure of nitrogen to the total pressure of reactive gas mixture was increased from 0.1 to 0.5. It is established that most significant changes in the relative content of Ti, Al, and Ta in as-deposited coatings take place when this ratio is varied from 0.1 to 0.3. The observed changes in the elemental composition of Ti1 –x–yAlxTаyN coatings do not influence their phase composition, but lead to changes in the microstructure and mechanical characteristics.

TiAlSiCN coatings were deposited by radio frequency reactive magnetron co-sputtering. In the coatings, the Si content is tuned by using targets with different Si additions. The structures and mechanical properties of the TiAlSiCN coatings were strongly depended on the Si content. The Si ~3 at.% sample exhibits the highest hardness of 38 GPa among the coatings prepared in this work. The nanocomposite microstructure containing B1-TiN nanocrystals with C:N ≈ 1:1 and combined C, SiNx and SiCx amorphous phases is attributed to the enhanced hardness.

In this work, we have investigated multilayer structures in which TiNx as an IR reflector on the substrate due to its high infrared reflectivity, TiNxOy coatings serve as the solar absorbers, and a bi-layer N-doped TiO2/SiO2 or HfO2 layer for surface anti-reflection. Both the TiNx and TiNxOy layers were first optimized. Selected TiNx and TiNxOy layers were then used to fabricate the multilayered structures. Optical properties were assessed at room temperature and high temperatures up to 800 °C. While the multilayered structures having bi-layer N-doped TiO2/SiO2 as the anti-reflection layer show excellent absorption and emission up to 600 °C, much reduced absorption where obtained at 800 °C. The use of HfO2 layer to replace SiO2 improves the absorption at 800 °C. The relationship between material characteristics and optical performance, which has not been understood, is addressed in this study. Excellent high temperature selectivity is demonstrated.

To study the tribological behavior of a-C: WC films in the marine environment, the a-C: WC films fabricated by reactive magnetron sputter technique with different bias voltages were reciprocally sliding against Si3N4 balls in artificial seawater. Results showed that the a-C: WC film was an amorphous matrix mixed with plenty of short-range ordered structures in sub-nano scale. Excellent tribological performance of the a-C: WC film in seawater could be achieved when the sub-nano-structure possessed excellent overall mechanical properties in combination with fewer growth defects on the surface. The lowest COF and wear rate for a-C: WC film (−30 V) in seawater were 0.12 and 6.2 × 10−8 mm3N−1m−1, respectively. The results demonstrated the potential application of a-C: WC films as protective surfaces in marine environments.

The goal of this paper is the offline parameter identification of the Berg model, intended to be used for magnetron sputtering and thin film deposition process control. A graphical parameter estimation method is developed using simplified equations that contain only the most significant terms in both metallic and poisoned modes of operation. The approximations are based on numerical examples. Special experiment conditions are also formulated that better facilitate the identification of some model parameters.

Deposition of ceramic hard coatings are paramount in surface engineering as a strategy for protecting metallic surfaces of severe wear, many times present in industrial applications. Among the options of materials for this purpose, the transition metal nitrides are some of the most common. Cr-Al-N present interesting mechanical and anti-oxidation properties. Along with the choice of materials, the route of deposition is a major parameter to be taken in consideration and thoroughly studied to optimize the performance of the film solution. In this thesis, Cr-Al-N coatings were deposited over stainless steel substrate using dcMS and HiPIMS and its impact on the properties of the films were investigated. The coatings presented high concentration of N, possibly due to target poisoning during reactive depositions. The samples produced using 70/30 at % target exhibited better mechanical performance as consequence of the larger amount of Al in solid solution. HiPIMS films presented improved properties and densification caused by the higher ionization and consequently higher energy in comparison with dcMS manufactured samples. The nitride coatings were produced using a novel technique in which the substrate is oscillated continuously in front of the target to produce nanostructured coatings by varying the angle of incidence of the sputtered material. This technique named Dynamic Glancing Angle Deposition (DGLAD) was found responsible for creating misorientation gradients along the grains. These features combined with the zigzag shape of grain boundaries contributed to enhancement in hardness and wear resistance, especially when larger oscillatory ranges were used. DGLAD is proved as a technique capable of positively influence microstructure, deposition rate and mechanical performance of the Cr-Al-N coatings. A deposição de recobrimentos cerâmicos duros é fundamental na engenharia de superfícies como uma das estratégias para proteção de superfícies metálicas contra condições de desgaste severo em aplicações industriais. Dentre as opções de materiais disponíveis para essa finalidade, nitretos de metais de transição são algumas das mais comuns. Cr-Al-N apresenta interessantes propriedades mecânicas e de resistência à oxidação, sendo uma opção relevante. Além da escolha do material, a via de deposição é um importante parâmetro a ser levado em consideração e estudado em detalhes quando se desenvolve soluções de recobrimentos. Nesta tese, recobrimentos de Cr-Al-N foram depositados sobre substratos de aço inoxidável fazendo uso das técnicas de HiPIMS e dcMS. O impacto da escolha de técnicas e de seus parâmetros nas propriedades dos filmes foram investigados. Os recobrimentos apresentaram altos teores de N, provavelmente devido ao processo de envenenamento dos alvos ricos em Al durante a pulverização catódica reativa. As amostras produzidas usando alvos precursores com composição atômica de 70/30 % Al/Cr mostram propriedades mecânicas mais relevantes do ponto de vista de dureza e H3 /Er2 devido à adição de maiores quantidades de Al em solução sólida. Os filmes produzidos por HiPIMS apresentaram maior dureza e densificação em comparação aos produzidos por dcMS devido à maior taxa de ionização, e subsequente maior energia de deposição da técnica pulsada. Os nitretos foram fabricados utilizando uma técnica recentemente desenvolvida, em que o substrato é continuamente oscilado na frente do alvo durante a deposição, garantindo a variação constante do ângulo de chegada do fluxo de material proveniente do alvo com relação à superfície da amostra. Esta técnica recebeu o nome de DGLAD (Dynamic Glancing Angle Deposition). A variação no ângulo de incidência do fluxo causa a formação de nanoestruturas ao longo do filme, com grãos apresentando formatos corrugados. Observou-se que estas estruturas geram gradientes de misorientations ao longo dos grãos, e em combinação com a natureza em zigue zague dos contornos de grãos são capazes de aumentar a dureza e a resistência ao desgaste dos recobrimentos, especialmente quando fabricados utilizando-se grandes limites de ângulos de oscilação. A técnica DGLAD se mostrou capaz de controlar positivamente o desempenho e a taxa de deposição dos filmes de Cr-Al-N, posicionando-se como uma importante alternativa para aplicações industriais.

Direct current (DC) reactive magnetron sputtering is as an efficient method for enhancing the biocompatibility of poly(ε-caprolactone) (PCL) scaffolds. However, the PCL chemical bonding state, the composition of the deposited coating, and their interaction with immune cells remain unknown. Herein, we demonstrated that the DC reactive magnetron sputtering of the titanium target in a nitrogen atmosphere leads to the formation of nitrogen-containing moieties and the titanium dioxide coating on the scaffold surface. We have provided the possible mechanism of PCL fragmentation and coating formation supported by XPS results and DFT calculations. Our preliminary biological studies suggest that DC reactive magnetron sputtering of the titanium target could be an effective tool to control macrophage functional responses toward PCL scaffolds as it allows to inhibit respiratory burst while retaining cell viability and scavenging activity.

In this work, we explore the addition of Ti ribbons on the racetrack of a Zr target to prepare Zr-O-N films including Ti, by reactive magnetron sputtering with a mixture of N2 and O2 as reactive gases. This approach is simple and not invasive, it avoids the modification of the target and minimizes its contamination. These films were compared in terms of chemical composition, density, film growth and crystallographic structure with others prepared in identical conditions without Ti ribbons. In addition, the composition and density of the films were correlated with crystallographic references from literature. The color and electrical properties of the films were evaluated as well. It was observed that poisoning of the Zr target is promoted by the increase of the N2 + O2 flow and the reduction of magnetron current, but it is retarded by the introduction of the Ti ribbons. This effect was particularly remarkable at lower target current, since the sputtering is confined in areas nearer to the racetrack, where the Ti ribbons are located. To account for the poisoning of the target and compare it among the different samples, a ‘poisoning parameter’ was defined, using a combination of the chemical composition of the films and the deposition rates. The color and electrical properties of the films correlate surprisingly well with their oxygen-to-metal ratio, while the concentration of N does not seem to play any significant role., The financial support of Portuguese Foundation of Science and Technology (FCT), under the projects IF/00671/2013, M-ERA-NET2/0012/2016, and Strategic Funding UIDB/04650/2020 are gratefully acknowledged. The financial support from the Basque Government Industry Department under the ELKARTEK program is also acknowledged.

CrAlN films were synthesized by DC reactive magnetron sputtering. The influence of the aluminium content on the microstructure, hardness and the friction coefficient of the CrAlN films have been investigated. Results indicate that all CrAlN coatings present a columnar and dense structure. Also, CrAlN coatings present a better hardness than CrN coating. The increase of Al rate from 3.5 to 11% is accompanied by a decrease of hardness from 28 to 24 GPa and then it increases for an Al rate of 24%. The addition of Al to the CrN system causes an increase of the friction coefficient and the wear resistance.

The chapter goes onto explore the impact of sputtering parameters on structural, optical, and mechanical properties of reactive magnetron sputtered ZnO thin film. Stress relaxed and room temperature deposited ZnO film is highly desirable from fabrication aspects. Oxygen partial pressure is varied from 30 to 60% and c-axis oriented ZnO (002) thin films are prepared at room temperature. The stress varies in −0.06 × 109 to −2.27 × 109 dyne/cm2 range, and compressive in nature. A detailed characterization of ZnO sputtered film is carried out in order to correlate the mechanical, structural, and optical properties of thin film. A theoretical model has been proposed to understand the consequences of oxygen-induced stress in ZnO thin films. It is established that nearly stress-free, single-phase, and highly c-axis oriented ZnO thin film can be deposited using a unique combination of sputter parameters.